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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
commit483eb2f56657e8e7f419ab1a4fab8dce9ade8609 (patch)
treee5d88d25d870d5dedacb6bbdbe2a966086a0a5cf /src/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch
parentInitial commit. (diff)
downloadceph-483eb2f56657e8e7f419ab1a4fab8dce9ade8609.tar.xz
ceph-483eb2f56657e8e7f419ab1a4fab8dce9ade8609.zip
Adding upstream version 14.2.21.upstream/14.2.21upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch')
-rw-r--r--src/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch13285
1 files changed, 13285 insertions, 0 deletions
diff --git a/src/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch b/src/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch
new file mode 100644
index 00000000..c3bbaed7
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+++ b/src/zstd/contrib/linux-kernel/0002-lib-Add-zstd-modules.patch
@@ -0,0 +1,13285 @@
+From 2b29ec569f8438a0307debd29873859ca6d407fc Mon Sep 17 00:00:00 2001
+From: Nick Terrell <terrelln@fb.com>
+Date: Mon, 17 Jul 2017 17:08:19 -0700
+Subject: [PATCH v5 2/5] lib: Add zstd modules
+
+Add zstd compression and decompression kernel modules.
+zstd offers a wide varity of compression speed and quality trade-offs.
+It can compress at speeds approaching lz4, and quality approaching lzma.
+zstd decompressions at speeds more than twice as fast as zlib, and
+decompression speed remains roughly the same across all compression levels.
+
+The code was ported from the upstream zstd source repository. The
+`linux/zstd.h` header was modified to match linux kernel style.
+The cross-platform and allocation code was stripped out. Instead zstd
+requires the caller to pass a preallocated workspace. The source files
+were clang-formatted [1] to match the Linux Kernel style as much as
+possible. Otherwise, the code was unmodified. We would like to avoid
+as much further manual modification to the source code as possible, so it
+will be easier to keep the kernel zstd up to date.
+
+I benchmarked zstd compression as a special character device. I ran zstd
+and zlib compression at several levels, as well as performing no
+compression, which measure the time spent copying the data to kernel space.
+Data is passed to the compresser 4096 B at a time. The benchmark file is
+located in the upstream zstd source repository under
+`contrib/linux-kernel/zstd_compress_test.c` [2].
+
+I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM.
+The VM is running on a MacBook Pro with a 3.1 GHz Intel Core i7 processor,
+16 GB of RAM, and a SSD. I benchmarked using `silesia.tar` [3], which is
+211,988,480 B large. Run the following commands for the benchmark:
+
+ sudo modprobe zstd_compress_test
+ sudo mknod zstd_compress_test c 245 0
+ sudo cp silesia.tar zstd_compress_test
+
+The time is reported by the time of the userland `cp`.
+The MB/s is computed with
+
+ 1,536,217,008 B / time(buffer size, hash)
+
+which includes the time to copy from userland.
+The Adjusted MB/s is computed with
+
+ 1,536,217,088 B / (time(buffer size, hash) - time(buffer size, none)).
+
+The memory reported is the amount of memory the compressor requests.
+
+| Method | Size (B) | Time (s) | Ratio | MB/s | Adj MB/s | Mem (MB) |
+|----------|----------|----------|-------|---------|----------|----------|
+| none | 11988480 | 0.100 | 1 | 2119.88 | - | - |
+| zstd -1 | 73645762 | 1.044 | 2.878 | 203.05 | 224.56 | 1.23 |
+| zstd -3 | 66988878 | 1.761 | 3.165 | 120.38 | 127.63 | 2.47 |
+| zstd -5 | 65001259 | 2.563 | 3.261 | 82.71 | 86.07 | 2.86 |
+| zstd -10 | 60165346 | 13.242 | 3.523 | 16.01 | 16.13 | 13.22 |
+| zstd -15 | 58009756 | 47.601 | 3.654 | 4.45 | 4.46 | 21.61 |
+| zstd -19 | 54014593 | 102.835 | 3.925 | 2.06 | 2.06 | 60.15 |
+| zlib -1 | 77260026 | 2.895 | 2.744 | 73.23 | 75.85 | 0.27 |
+| zlib -3 | 72972206 | 4.116 | 2.905 | 51.50 | 52.79 | 0.27 |
+| zlib -6 | 68190360 | 9.633 | 3.109 | 22.01 | 22.24 | 0.27 |
+| zlib -9 | 67613382 | 22.554 | 3.135 | 9.40 | 9.44 | 0.27 |
+
+I benchmarked zstd decompression using the same method on the same machine.
+The benchmark file is located in the upstream zstd repo under
+`contrib/linux-kernel/zstd_decompress_test.c` [4]. The memory reported is
+the amount of memory required to decompress data compressed with the given
+compression level. If you know the maximum size of your input, you can
+reduce the memory usage of decompression irrespective of the compression
+level.
+
+| Method | Time (s) | MB/s | Adjusted MB/s | Memory (MB) |
+|----------|----------|---------|---------------|-------------|
+| none | 0.025 | 8479.54 | - | - |
+| zstd -1 | 0.358 | 592.15 | 636.60 | 0.84 |
+| zstd -3 | 0.396 | 535.32 | 571.40 | 1.46 |
+| zstd -5 | 0.396 | 535.32 | 571.40 | 1.46 |
+| zstd -10 | 0.374 | 566.81 | 607.42 | 2.51 |
+| zstd -15 | 0.379 | 559.34 | 598.84 | 4.61 |
+| zstd -19 | 0.412 | 514.54 | 547.77 | 8.80 |
+| zlib -1 | 0.940 | 225.52 | 231.68 | 0.04 |
+| zlib -3 | 0.883 | 240.08 | 247.07 | 0.04 |
+| zlib -6 | 0.844 | 251.17 | 258.84 | 0.04 |
+| zlib -9 | 0.837 | 253.27 | 287.64 | 0.04 |
+
+Tested in userland using the test-suite in the zstd repo under
+`contrib/linux-kernel/test/UserlandTest.cpp` [5] by mocking the kernel
+functions. Fuzz tested using libfuzzer [6] with the fuzz harnesses under
+`contrib/linux-kernel/test/{RoundTripCrash.c,DecompressCrash.c}` [7] [8]
+with ASAN, UBSAN, and MSAN. Additionaly, it was tested while testing the
+BtrFS and SquashFS patches coming next.
+
+[1] https://clang.llvm.org/docs/ClangFormat.html
+[2] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/zstd_compress_test.c
+[3] http://sun.aei.polsl.pl/~sdeor/index.php?page=silesia
+[4] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/zstd_decompress_test.c
+[5] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/test/UserlandTest.cpp
+[6] http://llvm.org/docs/LibFuzzer.html
+[7] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/test/RoundTripCrash.c
+[8] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/test/DecompressCrash.c
+
+zstd source repository: https://github.com/facebook/zstd
+
+Signed-off-by: Nick Terrell <terrelln@fb.com>
+---
+v1 -> v2:
+- Use div_u64() for division of u64s
+- Reduce stack usage of ZSTD_compressSequences(), ZSTD_buildSeqTable(),
+ ZSTD_decompressSequencesLong(), FSE_buildDTable(), FSE_decompress_wksp(),
+ HUF_writeCTable(), HUF_readStats(), HUF_readCTable(),
+ HUF_compressWeights(), HUF_readDTableX2(), and HUF_readDTableX4()
+- No function uses more than 400 B of stack space
+
+v2 -> v3:
+- Work around gcc-7 bug https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388
+- Fix bug in dictionary compression from upstream commit cc1522351f
+
+v3 -> v4:
+- Fix minor compiler warnings
+
+v4 -> v5:
+- Fix rare compression bug from upstream commit 308047eb5d
+- Fix bug introduced in v3 when working around the gcc-7 bug
+
+ include/linux/zstd.h | 1155 +++++++++++++++
+ lib/Kconfig | 8 +
+ lib/Makefile | 2 +
+ lib/zstd/Makefile | 18 +
+ lib/zstd/bitstream.h | 374 +++++
+ lib/zstd/compress.c | 3482 +++++++++++++++++++++++++++++++++++++++++++++
+ lib/zstd/decompress.c | 2526 ++++++++++++++++++++++++++++++++
+ lib/zstd/entropy_common.c | 243 ++++
+ lib/zstd/error_private.h | 51 +
+ lib/zstd/fse.h | 575 ++++++++
+ lib/zstd/fse_compress.c | 795 +++++++++++
+ lib/zstd/fse_decompress.c | 332 +++++
+ lib/zstd/huf.h | 212 +++
+ lib/zstd/huf_compress.c | 770 ++++++++++
+ lib/zstd/huf_decompress.c | 960 +++++++++++++
+ lib/zstd/mem.h | 149 ++
+ lib/zstd/zstd_common.c | 73 +
+ lib/zstd/zstd_internal.h | 261 ++++
+ lib/zstd/zstd_opt.h | 1012 +++++++++++++
+ 19 files changed, 12998 insertions(+)
+ create mode 100644 include/linux/zstd.h
+ create mode 100644 lib/zstd/Makefile
+ create mode 100644 lib/zstd/bitstream.h
+ create mode 100644 lib/zstd/compress.c
+ create mode 100644 lib/zstd/decompress.c
+ create mode 100644 lib/zstd/entropy_common.c
+ create mode 100644 lib/zstd/error_private.h
+ create mode 100644 lib/zstd/fse.h
+ create mode 100644 lib/zstd/fse_compress.c
+ create mode 100644 lib/zstd/fse_decompress.c
+ create mode 100644 lib/zstd/huf.h
+ create mode 100644 lib/zstd/huf_compress.c
+ create mode 100644 lib/zstd/huf_decompress.c
+ create mode 100644 lib/zstd/mem.h
+ create mode 100644 lib/zstd/zstd_common.c
+ create mode 100644 lib/zstd/zstd_internal.h
+ create mode 100644 lib/zstd/zstd_opt.h
+
+diff --git a/include/linux/zstd.h b/include/linux/zstd.h
+new file mode 100644
+index 0000000..305efd0
+--- /dev/null
++++ b/include/linux/zstd.h
+@@ -0,0 +1,1155 @@
++/*
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++#ifndef ZSTD_H
++#define ZSTD_H
++
++/* ====== Dependency ======*/
++#include <linux/types.h> /* size_t */
++
++
++/*-*****************************************************************************
++ * Introduction
++ *
++ * zstd, short for Zstandard, is a fast lossless compression algorithm,
++ * targeting real-time compression scenarios at zlib-level and better
++ * compression ratios. The zstd compression library provides in-memory
++ * compression and decompression functions. The library supports compression
++ * levels from 1 up to ZSTD_maxCLevel() which is 22. Levels >= 20, labeled
++ * ultra, should be used with caution, as they require more memory.
++ * Compression can be done in:
++ * - a single step, reusing a context (described as Explicit memory management)
++ * - unbounded multiple steps (described as Streaming compression)
++ * The compression ratio achievable on small data can be highly improved using
++ * compression with a dictionary in:
++ * - a single step (described as Simple dictionary API)
++ * - a single step, reusing a dictionary (described as Fast dictionary API)
++ ******************************************************************************/
++
++/*====== Helper functions ======*/
++
++/**
++ * enum ZSTD_ErrorCode - zstd error codes
++ *
++ * Functions that return size_t can be checked for errors using ZSTD_isError()
++ * and the ZSTD_ErrorCode can be extracted using ZSTD_getErrorCode().
++ */
++typedef enum {
++ ZSTD_error_no_error,
++ ZSTD_error_GENERIC,
++ ZSTD_error_prefix_unknown,
++ ZSTD_error_version_unsupported,
++ ZSTD_error_parameter_unknown,
++ ZSTD_error_frameParameter_unsupported,
++ ZSTD_error_frameParameter_unsupportedBy32bits,
++ ZSTD_error_frameParameter_windowTooLarge,
++ ZSTD_error_compressionParameter_unsupported,
++ ZSTD_error_init_missing,
++ ZSTD_error_memory_allocation,
++ ZSTD_error_stage_wrong,
++ ZSTD_error_dstSize_tooSmall,
++ ZSTD_error_srcSize_wrong,
++ ZSTD_error_corruption_detected,
++ ZSTD_error_checksum_wrong,
++ ZSTD_error_tableLog_tooLarge,
++ ZSTD_error_maxSymbolValue_tooLarge,
++ ZSTD_error_maxSymbolValue_tooSmall,
++ ZSTD_error_dictionary_corrupted,
++ ZSTD_error_dictionary_wrong,
++ ZSTD_error_dictionaryCreation_failed,
++ ZSTD_error_maxCode
++} ZSTD_ErrorCode;
++
++/**
++ * ZSTD_maxCLevel() - maximum compression level available
++ *
++ * Return: Maximum compression level available.
++ */
++int ZSTD_maxCLevel(void);
++/**
++ * ZSTD_compressBound() - maximum compressed size in worst case scenario
++ * @srcSize: The size of the data to compress.
++ *
++ * Return: The maximum compressed size in the worst case scenario.
++ */
++size_t ZSTD_compressBound(size_t srcSize);
++/**
++ * ZSTD_isError() - tells if a size_t function result is an error code
++ * @code: The function result to check for error.
++ *
++ * Return: Non-zero iff the code is an error.
++ */
++static __attribute__((unused)) unsigned int ZSTD_isError(size_t code)
++{
++ return code > (size_t)-ZSTD_error_maxCode;
++}
++/**
++ * ZSTD_getErrorCode() - translates an error function result to a ZSTD_ErrorCode
++ * @functionResult: The result of a function for which ZSTD_isError() is true.
++ *
++ * Return: The ZSTD_ErrorCode corresponding to the functionResult or 0
++ * if the functionResult isn't an error.
++ */
++static __attribute__((unused)) ZSTD_ErrorCode ZSTD_getErrorCode(
++ size_t functionResult)
++{
++ if (!ZSTD_isError(functionResult))
++ return (ZSTD_ErrorCode)0;
++ return (ZSTD_ErrorCode)(0 - functionResult);
++}
++
++/**
++ * enum ZSTD_strategy - zstd compression search strategy
++ *
++ * From faster to stronger.
++ */
++typedef enum {
++ ZSTD_fast,
++ ZSTD_dfast,
++ ZSTD_greedy,
++ ZSTD_lazy,
++ ZSTD_lazy2,
++ ZSTD_btlazy2,
++ ZSTD_btopt,
++ ZSTD_btopt2
++} ZSTD_strategy;
++
++/**
++ * struct ZSTD_compressionParameters - zstd compression parameters
++ * @windowLog: Log of the largest match distance. Larger means more
++ * compression, and more memory needed during decompression.
++ * @chainLog: Fully searched segment. Larger means more compression, slower,
++ * and more memory (useless for fast).
++ * @hashLog: Dispatch table. Larger means more compression,
++ * slower, and more memory.
++ * @searchLog: Number of searches. Larger means more compression and slower.
++ * @searchLength: Match length searched. Larger means faster decompression,
++ * sometimes less compression.
++ * @targetLength: Acceptable match size for optimal parser (only). Larger means
++ * more compression, and slower.
++ * @strategy: The zstd compression strategy.
++ */
++typedef struct {
++ unsigned int windowLog;
++ unsigned int chainLog;
++ unsigned int hashLog;
++ unsigned int searchLog;
++ unsigned int searchLength;
++ unsigned int targetLength;
++ ZSTD_strategy strategy;
++} ZSTD_compressionParameters;
++
++/**
++ * struct ZSTD_frameParameters - zstd frame parameters
++ * @contentSizeFlag: Controls whether content size will be present in the frame
++ * header (when known).
++ * @checksumFlag: Controls whether a 32-bit checksum is generated at the end
++ * of the frame for error detection.
++ * @noDictIDFlag: Controls whether dictID will be saved into the frame header
++ * when using dictionary compression.
++ *
++ * The default value is all fields set to 0.
++ */
++typedef struct {
++ unsigned int contentSizeFlag;
++ unsigned int checksumFlag;
++ unsigned int noDictIDFlag;
++} ZSTD_frameParameters;
++
++/**
++ * struct ZSTD_parameters - zstd parameters
++ * @cParams: The compression parameters.
++ * @fParams: The frame parameters.
++ */
++typedef struct {
++ ZSTD_compressionParameters cParams;
++ ZSTD_frameParameters fParams;
++} ZSTD_parameters;
++
++/**
++ * ZSTD_getCParams() - returns ZSTD_compressionParameters for selected level
++ * @compressionLevel: The compression level from 1 to ZSTD_maxCLevel().
++ * @estimatedSrcSize: The estimated source size to compress or 0 if unknown.
++ * @dictSize: The dictionary size or 0 if a dictionary isn't being used.
++ *
++ * Return: The selected ZSTD_compressionParameters.
++ */
++ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel,
++ unsigned long long estimatedSrcSize, size_t dictSize);
++
++/**
++ * ZSTD_getParams() - returns ZSTD_parameters for selected level
++ * @compressionLevel: The compression level from 1 to ZSTD_maxCLevel().
++ * @estimatedSrcSize: The estimated source size to compress or 0 if unknown.
++ * @dictSize: The dictionary size or 0 if a dictionary isn't being used.
++ *
++ * The same as ZSTD_getCParams() except also selects the default frame
++ * parameters (all zero).
++ *
++ * Return: The selected ZSTD_parameters.
++ */
++ZSTD_parameters ZSTD_getParams(int compressionLevel,
++ unsigned long long estimatedSrcSize, size_t dictSize);
++
++/*-*************************************
++ * Explicit memory management
++ **************************************/
++
++/**
++ * ZSTD_CCtxWorkspaceBound() - amount of memory needed to initialize a ZSTD_CCtx
++ * @cParams: The compression parameters to be used for compression.
++ *
++ * If multiple compression parameters might be used, the caller must call
++ * ZSTD_CCtxWorkspaceBound() for each set of parameters and use the maximum
++ * size.
++ *
++ * Return: A lower bound on the size of the workspace that is passed to
++ * ZSTD_initCCtx().
++ */
++size_t ZSTD_CCtxWorkspaceBound(ZSTD_compressionParameters cParams);
++
++/**
++ * struct ZSTD_CCtx - the zstd compression context
++ *
++ * When compressing many times it is recommended to allocate a context just once
++ * and reuse it for each successive compression operation.
++ */
++typedef struct ZSTD_CCtx_s ZSTD_CCtx;
++/**
++ * ZSTD_initCCtx() - initialize a zstd compression context
++ * @workspace: The workspace to emplace the context into. It must outlive
++ * the returned context.
++ * @workspaceSize: The size of workspace. Use ZSTD_CCtxWorkspaceBound() to
++ * determine how large the workspace must be.
++ *
++ * Return: A compression context emplaced into workspace.
++ */
++ZSTD_CCtx *ZSTD_initCCtx(void *workspace, size_t workspaceSize);
++
++/**
++ * ZSTD_compressCCtx() - compress src into dst
++ * @ctx: The context. Must have been initialized with a workspace at
++ * least as large as ZSTD_CCtxWorkspaceBound(params.cParams).
++ * @dst: The buffer to compress src into.
++ * @dstCapacity: The size of the destination buffer. May be any size, but
++ * ZSTD_compressBound(srcSize) is guaranteed to be large enough.
++ * @src: The data to compress.
++ * @srcSize: The size of the data to compress.
++ * @params: The parameters to use for compression. See ZSTD_getParams().
++ *
++ * Return: The compressed size or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_compressCCtx(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize, ZSTD_parameters params);
++
++/**
++ * ZSTD_DCtxWorkspaceBound() - amount of memory needed to initialize a ZSTD_DCtx
++ *
++ * Return: A lower bound on the size of the workspace that is passed to
++ * ZSTD_initDCtx().
++ */
++size_t ZSTD_DCtxWorkspaceBound(void);
++
++/**
++ * struct ZSTD_DCtx - the zstd decompression context
++ *
++ * When decompressing many times it is recommended to allocate a context just
++ * once and reuse it for each successive decompression operation.
++ */
++typedef struct ZSTD_DCtx_s ZSTD_DCtx;
++/**
++ * ZSTD_initDCtx() - initialize a zstd decompression context
++ * @workspace: The workspace to emplace the context into. It must outlive
++ * the returned context.
++ * @workspaceSize: The size of workspace. Use ZSTD_DCtxWorkspaceBound() to
++ * determine how large the workspace must be.
++ *
++ * Return: A decompression context emplaced into workspace.
++ */
++ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize);
++
++/**
++ * ZSTD_decompressDCtx() - decompress zstd compressed src into dst
++ * @ctx: The decompression context.
++ * @dst: The buffer to decompress src into.
++ * @dstCapacity: The size of the destination buffer. Must be at least as large
++ * as the decompressed size. If the caller cannot upper bound the
++ * decompressed size, then it's better to use the streaming API.
++ * @src: The zstd compressed data to decompress. Multiple concatenated
++ * frames and skippable frames are allowed.
++ * @srcSize: The exact size of the data to decompress.
++ *
++ * Return: The decompressed size or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_decompressDCtx(ZSTD_DCtx *ctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize);
++
++/*-************************
++ * Simple dictionary API
++ **************************/
++
++/**
++ * ZSTD_compress_usingDict() - compress src into dst using a dictionary
++ * @ctx: The context. Must have been initialized with a workspace at
++ * least as large as ZSTD_CCtxWorkspaceBound(params.cParams).
++ * @dst: The buffer to compress src into.
++ * @dstCapacity: The size of the destination buffer. May be any size, but
++ * ZSTD_compressBound(srcSize) is guaranteed to be large enough.
++ * @src: The data to compress.
++ * @srcSize: The size of the data to compress.
++ * @dict: The dictionary to use for compression.
++ * @dictSize: The size of the dictionary.
++ * @params: The parameters to use for compression. See ZSTD_getParams().
++ *
++ * Compression using a predefined dictionary. The same dictionary must be used
++ * during decompression.
++ *
++ * Return: The compressed size or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_compress_usingDict(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize, const void *dict, size_t dictSize,
++ ZSTD_parameters params);
++
++/**
++ * ZSTD_decompress_usingDict() - decompress src into dst using a dictionary
++ * @ctx: The decompression context.
++ * @dst: The buffer to decompress src into.
++ * @dstCapacity: The size of the destination buffer. Must be at least as large
++ * as the decompressed size. If the caller cannot upper bound the
++ * decompressed size, then it's better to use the streaming API.
++ * @src: The zstd compressed data to decompress. Multiple concatenated
++ * frames and skippable frames are allowed.
++ * @srcSize: The exact size of the data to decompress.
++ * @dict: The dictionary to use for decompression. The same dictionary
++ * must've been used to compress the data.
++ * @dictSize: The size of the dictionary.
++ *
++ * Return: The decompressed size or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_decompress_usingDict(ZSTD_DCtx *ctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize, const void *dict, size_t dictSize);
++
++/*-**************************
++ * Fast dictionary API
++ ***************************/
++
++/**
++ * ZSTD_CDictWorkspaceBound() - memory needed to initialize a ZSTD_CDict
++ * @cParams: The compression parameters to be used for compression.
++ *
++ * Return: A lower bound on the size of the workspace that is passed to
++ * ZSTD_initCDict().
++ */
++size_t ZSTD_CDictWorkspaceBound(ZSTD_compressionParameters cParams);
++
++/**
++ * struct ZSTD_CDict - a digested dictionary to be used for compression
++ */
++typedef struct ZSTD_CDict_s ZSTD_CDict;
++
++/**
++ * ZSTD_initCDict() - initialize a digested dictionary for compression
++ * @dictBuffer: The dictionary to digest. The buffer is referenced by the
++ * ZSTD_CDict so it must outlive the returned ZSTD_CDict.
++ * @dictSize: The size of the dictionary.
++ * @params: The parameters to use for compression. See ZSTD_getParams().
++ * @workspace: The workspace. It must outlive the returned ZSTD_CDict.
++ * @workspaceSize: The workspace size. Must be at least
++ * ZSTD_CDictWorkspaceBound(params.cParams).
++ *
++ * When compressing multiple messages / blocks with the same dictionary it is
++ * recommended to load it just once. The ZSTD_CDict merely references the
++ * dictBuffer, so it must outlive the returned ZSTD_CDict.
++ *
++ * Return: The digested dictionary emplaced into workspace.
++ */
++ZSTD_CDict *ZSTD_initCDict(const void *dictBuffer, size_t dictSize,
++ ZSTD_parameters params, void *workspace, size_t workspaceSize);
++
++/**
++ * ZSTD_compress_usingCDict() - compress src into dst using a ZSTD_CDict
++ * @ctx: The context. Must have been initialized with a workspace at
++ * least as large as ZSTD_CCtxWorkspaceBound(cParams) where
++ * cParams are the compression parameters used to initialize the
++ * cdict.
++ * @dst: The buffer to compress src into.
++ * @dstCapacity: The size of the destination buffer. May be any size, but
++ * ZSTD_compressBound(srcSize) is guaranteed to be large enough.
++ * @src: The data to compress.
++ * @srcSize: The size of the data to compress.
++ * @cdict: The digested dictionary to use for compression.
++ * @params: The parameters to use for compression. See ZSTD_getParams().
++ *
++ * Compression using a digested dictionary. The same dictionary must be used
++ * during decompression.
++ *
++ * Return: The compressed size or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_compress_usingCDict(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize, const ZSTD_CDict *cdict);
++
++
++/**
++ * ZSTD_DDictWorkspaceBound() - memory needed to initialize a ZSTD_DDict
++ *
++ * Return: A lower bound on the size of the workspace that is passed to
++ * ZSTD_initDDict().
++ */
++size_t ZSTD_DDictWorkspaceBound(void);
++
++/**
++ * struct ZSTD_DDict - a digested dictionary to be used for decompression
++ */
++typedef struct ZSTD_DDict_s ZSTD_DDict;
++
++/**
++ * ZSTD_initDDict() - initialize a digested dictionary for decompression
++ * @dictBuffer: The dictionary to digest. The buffer is referenced by the
++ * ZSTD_DDict so it must outlive the returned ZSTD_DDict.
++ * @dictSize: The size of the dictionary.
++ * @workspace: The workspace. It must outlive the returned ZSTD_DDict.
++ * @workspaceSize: The workspace size. Must be at least
++ * ZSTD_DDictWorkspaceBound().
++ *
++ * When decompressing multiple messages / blocks with the same dictionary it is
++ * recommended to load it just once. The ZSTD_DDict merely references the
++ * dictBuffer, so it must outlive the returned ZSTD_DDict.
++ *
++ * Return: The digested dictionary emplaced into workspace.
++ */
++ZSTD_DDict *ZSTD_initDDict(const void *dictBuffer, size_t dictSize,
++ void *workspace, size_t workspaceSize);
++
++/**
++ * ZSTD_decompress_usingDDict() - decompress src into dst using a ZSTD_DDict
++ * @ctx: The decompression context.
++ * @dst: The buffer to decompress src into.
++ * @dstCapacity: The size of the destination buffer. Must be at least as large
++ * as the decompressed size. If the caller cannot upper bound the
++ * decompressed size, then it's better to use the streaming API.
++ * @src: The zstd compressed data to decompress. Multiple concatenated
++ * frames and skippable frames are allowed.
++ * @srcSize: The exact size of the data to decompress.
++ * @ddict: The digested dictionary to use for decompression. The same
++ * dictionary must've been used to compress the data.
++ *
++ * Return: The decompressed size or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst,
++ size_t dstCapacity, const void *src, size_t srcSize,
++ const ZSTD_DDict *ddict);
++
++
++/*-**************************
++ * Streaming
++ ***************************/
++
++/**
++ * struct ZSTD_inBuffer - input buffer for streaming
++ * @src: Start of the input buffer.
++ * @size: Size of the input buffer.
++ * @pos: Position where reading stopped. Will be updated.
++ * Necessarily 0 <= pos <= size.
++ */
++typedef struct ZSTD_inBuffer_s {
++ const void *src;
++ size_t size;
++ size_t pos;
++} ZSTD_inBuffer;
++
++/**
++ * struct ZSTD_outBuffer - output buffer for streaming
++ * @dst: Start of the output buffer.
++ * @size: Size of the output buffer.
++ * @pos: Position where writing stopped. Will be updated.
++ * Necessarily 0 <= pos <= size.
++ */
++typedef struct ZSTD_outBuffer_s {
++ void *dst;
++ size_t size;
++ size_t pos;
++} ZSTD_outBuffer;
++
++
++
++/*-*****************************************************************************
++ * Streaming compression - HowTo
++ *
++ * A ZSTD_CStream object is required to track streaming operation.
++ * Use ZSTD_initCStream() to initialize a ZSTD_CStream object.
++ * ZSTD_CStream objects can be reused multiple times on consecutive compression
++ * operations. It is recommended to re-use ZSTD_CStream in situations where many
++ * streaming operations will be achieved consecutively. Use one separate
++ * ZSTD_CStream per thread for parallel execution.
++ *
++ * Use ZSTD_compressStream() repetitively to consume input stream.
++ * The function will automatically update both `pos` fields.
++ * Note that it may not consume the entire input, in which case `pos < size`,
++ * and it's up to the caller to present again remaining data.
++ * It returns a hint for the preferred number of bytes to use as an input for
++ * the next function call.
++ *
++ * At any moment, it's possible to flush whatever data remains within internal
++ * buffer, using ZSTD_flushStream(). `output->pos` will be updated. There might
++ * still be some content left within the internal buffer if `output->size` is
++ * too small. It returns the number of bytes left in the internal buffer and
++ * must be called until it returns 0.
++ *
++ * ZSTD_endStream() instructs to finish a frame. It will perform a flush and
++ * write frame epilogue. The epilogue is required for decoders to consider a
++ * frame completed. Similar to ZSTD_flushStream(), it may not be able to flush
++ * the full content if `output->size` is too small. In which case, call again
++ * ZSTD_endStream() to complete the flush. It returns the number of bytes left
++ * in the internal buffer and must be called until it returns 0.
++ ******************************************************************************/
++
++/**
++ * ZSTD_CStreamWorkspaceBound() - memory needed to initialize a ZSTD_CStream
++ * @cParams: The compression parameters to be used for compression.
++ *
++ * Return: A lower bound on the size of the workspace that is passed to
++ * ZSTD_initCStream() and ZSTD_initCStream_usingCDict().
++ */
++size_t ZSTD_CStreamWorkspaceBound(ZSTD_compressionParameters cParams);
++
++/**
++ * struct ZSTD_CStream - the zstd streaming compression context
++ */
++typedef struct ZSTD_CStream_s ZSTD_CStream;
++
++/*===== ZSTD_CStream management functions =====*/
++/**
++ * ZSTD_initCStream() - initialize a zstd streaming compression context
++ * @params: The zstd compression parameters.
++ * @pledgedSrcSize: If params.fParams.contentSizeFlag == 1 then the caller must
++ * pass the source size (zero means empty source). Otherwise,
++ * the caller may optionally pass the source size, or zero if
++ * unknown.
++ * @workspace: The workspace to emplace the context into. It must outlive
++ * the returned context.
++ * @workspaceSize: The size of workspace.
++ * Use ZSTD_CStreamWorkspaceBound(params.cParams) to determine
++ * how large the workspace must be.
++ *
++ * Return: The zstd streaming compression context.
++ */
++ZSTD_CStream *ZSTD_initCStream(ZSTD_parameters params,
++ unsigned long long pledgedSrcSize, void *workspace,
++ size_t workspaceSize);
++
++/**
++ * ZSTD_initCStream_usingCDict() - initialize a streaming compression context
++ * @cdict: The digested dictionary to use for compression.
++ * @pledgedSrcSize: Optionally the source size, or zero if unknown.
++ * @workspace: The workspace to emplace the context into. It must outlive
++ * the returned context.
++ * @workspaceSize: The size of workspace. Call ZSTD_CStreamWorkspaceBound()
++ * with the cParams used to initialize the cdict to determine
++ * how large the workspace must be.
++ *
++ * Return: The zstd streaming compression context.
++ */
++ZSTD_CStream *ZSTD_initCStream_usingCDict(const ZSTD_CDict *cdict,
++ unsigned long long pledgedSrcSize, void *workspace,
++ size_t workspaceSize);
++
++/*===== Streaming compression functions =====*/
++/**
++ * ZSTD_resetCStream() - reset the context using parameters from creation
++ * @zcs: The zstd streaming compression context to reset.
++ * @pledgedSrcSize: Optionally the source size, or zero if unknown.
++ *
++ * Resets the context using the parameters from creation. Skips dictionary
++ * loading, since it can be reused. If `pledgedSrcSize` is non-zero the frame
++ * content size is always written into the frame header.
++ *
++ * Return: Zero or an error, which can be checked using ZSTD_isError().
++ */
++size_t ZSTD_resetCStream(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize);
++/**
++ * ZSTD_compressStream() - streaming compress some of input into output
++ * @zcs: The zstd streaming compression context.
++ * @output: Destination buffer. `output->pos` is updated to indicate how much
++ * compressed data was written.
++ * @input: Source buffer. `input->pos` is updated to indicate how much data was
++ * read. Note that it may not consume the entire input, in which case
++ * `input->pos < input->size`, and it's up to the caller to present
++ * remaining data again.
++ *
++ * The `input` and `output` buffers may be any size. Guaranteed to make some
++ * forward progress if `input` and `output` are not empty.
++ *
++ * Return: A hint for the number of bytes to use as the input for the next
++ * function call or an error, which can be checked using
++ * ZSTD_isError().
++ */
++size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output,
++ ZSTD_inBuffer *input);
++/**
++ * ZSTD_flushStream() - flush internal buffers into output
++ * @zcs: The zstd streaming compression context.
++ * @output: Destination buffer. `output->pos` is updated to indicate how much
++ * compressed data was written.
++ *
++ * ZSTD_flushStream() must be called until it returns 0, meaning all the data
++ * has been flushed. Since ZSTD_flushStream() causes a block to be ended,
++ * calling it too often will degrade the compression ratio.
++ *
++ * Return: The number of bytes still present within internal buffers or an
++ * error, which can be checked using ZSTD_isError().
++ */
++size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output);
++/**
++ * ZSTD_endStream() - flush internal buffers into output and end the frame
++ * @zcs: The zstd streaming compression context.
++ * @output: Destination buffer. `output->pos` is updated to indicate how much
++ * compressed data was written.
++ *
++ * ZSTD_endStream() must be called until it returns 0, meaning all the data has
++ * been flushed and the frame epilogue has been written.
++ *
++ * Return: The number of bytes still present within internal buffers or an
++ * error, which can be checked using ZSTD_isError().
++ */
++size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output);
++
++/**
++ * ZSTD_CStreamInSize() - recommended size for the input buffer
++ *
++ * Return: The recommended size for the input buffer.
++ */
++size_t ZSTD_CStreamInSize(void);
++/**
++ * ZSTD_CStreamOutSize() - recommended size for the output buffer
++ *
++ * When the output buffer is at least this large, it is guaranteed to be large
++ * enough to flush at least one complete compressed block.
++ *
++ * Return: The recommended size for the output buffer.
++ */
++size_t ZSTD_CStreamOutSize(void);
++
++
++
++/*-*****************************************************************************
++ * Streaming decompression - HowTo
++ *
++ * A ZSTD_DStream object is required to track streaming operations.
++ * Use ZSTD_initDStream() to initialize a ZSTD_DStream object.
++ * ZSTD_DStream objects can be re-used multiple times.
++ *
++ * Use ZSTD_decompressStream() repetitively to consume your input.
++ * The function will update both `pos` fields.
++ * If `input->pos < input->size`, some input has not been consumed.
++ * It's up to the caller to present again remaining data.
++ * If `output->pos < output->size`, decoder has flushed everything it could.
++ * Returns 0 iff a frame is completely decoded and fully flushed.
++ * Otherwise it returns a suggested next input size that will never load more
++ * than the current frame.
++ ******************************************************************************/
++
++/**
++ * ZSTD_DStreamWorkspaceBound() - memory needed to initialize a ZSTD_DStream
++ * @maxWindowSize: The maximum window size allowed for compressed frames.
++ *
++ * Return: A lower bound on the size of the workspace that is passed to
++ * ZSTD_initDStream() and ZSTD_initDStream_usingDDict().
++ */
++size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize);
++
++/**
++ * struct ZSTD_DStream - the zstd streaming decompression context
++ */
++typedef struct ZSTD_DStream_s ZSTD_DStream;
++/*===== ZSTD_DStream management functions =====*/
++/**
++ * ZSTD_initDStream() - initialize a zstd streaming decompression context
++ * @maxWindowSize: The maximum window size allowed for compressed frames.
++ * @workspace: The workspace to emplace the context into. It must outlive
++ * the returned context.
++ * @workspaceSize: The size of workspace.
++ * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine
++ * how large the workspace must be.
++ *
++ * Return: The zstd streaming decompression context.
++ */
++ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace,
++ size_t workspaceSize);
++/**
++ * ZSTD_initDStream_usingDDict() - initialize streaming decompression context
++ * @maxWindowSize: The maximum window size allowed for compressed frames.
++ * @ddict: The digested dictionary to use for decompression.
++ * @workspace: The workspace to emplace the context into. It must outlive
++ * the returned context.
++ * @workspaceSize: The size of workspace.
++ * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine
++ * how large the workspace must be.
++ *
++ * Return: The zstd streaming decompression context.
++ */
++ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize,
++ const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize);
++
++/*===== Streaming decompression functions =====*/
++/**
++ * ZSTD_resetDStream() - reset the context using parameters from creation
++ * @zds: The zstd streaming decompression context to reset.
++ *
++ * Resets the context using the parameters from creation. Skips dictionary
++ * loading, since it can be reused.
++ *
++ * Return: Zero or an error, which can be checked using ZSTD_isError().
++ */
++size_t ZSTD_resetDStream(ZSTD_DStream *zds);
++/**
++ * ZSTD_decompressStream() - streaming decompress some of input into output
++ * @zds: The zstd streaming decompression context.
++ * @output: Destination buffer. `output.pos` is updated to indicate how much
++ * decompressed data was written.
++ * @input: Source buffer. `input.pos` is updated to indicate how much data was
++ * read. Note that it may not consume the entire input, in which case
++ * `input.pos < input.size`, and it's up to the caller to present
++ * remaining data again.
++ *
++ * The `input` and `output` buffers may be any size. Guaranteed to make some
++ * forward progress if `input` and `output` are not empty.
++ * ZSTD_decompressStream() will not consume the last byte of the frame until
++ * the entire frame is flushed.
++ *
++ * Return: Returns 0 iff a frame is completely decoded and fully flushed.
++ * Otherwise returns a hint for the number of bytes to use as the input
++ * for the next function call or an error, which can be checked using
++ * ZSTD_isError(). The size hint will never load more than the frame.
++ */
++size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output,
++ ZSTD_inBuffer *input);
++
++/**
++ * ZSTD_DStreamInSize() - recommended size for the input buffer
++ *
++ * Return: The recommended size for the input buffer.
++ */
++size_t ZSTD_DStreamInSize(void);
++/**
++ * ZSTD_DStreamOutSize() - recommended size for the output buffer
++ *
++ * When the output buffer is at least this large, it is guaranteed to be large
++ * enough to flush at least one complete decompressed block.
++ *
++ * Return: The recommended size for the output buffer.
++ */
++size_t ZSTD_DStreamOutSize(void);
++
++
++/* --- Constants ---*/
++#define ZSTD_MAGICNUMBER 0xFD2FB528 /* >= v0.8.0 */
++#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U
++
++#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
++#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2)
++
++#define ZSTD_WINDOWLOG_MAX_32 27
++#define ZSTD_WINDOWLOG_MAX_64 27
++#define ZSTD_WINDOWLOG_MAX \
++ ((unsigned int)(sizeof(size_t) == 4 \
++ ? ZSTD_WINDOWLOG_MAX_32 \
++ : ZSTD_WINDOWLOG_MAX_64))
++#define ZSTD_WINDOWLOG_MIN 10
++#define ZSTD_HASHLOG_MAX ZSTD_WINDOWLOG_MAX
++#define ZSTD_HASHLOG_MIN 6
++#define ZSTD_CHAINLOG_MAX (ZSTD_WINDOWLOG_MAX+1)
++#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN
++#define ZSTD_HASHLOG3_MAX 17
++#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1)
++#define ZSTD_SEARCHLOG_MIN 1
++/* only for ZSTD_fast, other strategies are limited to 6 */
++#define ZSTD_SEARCHLENGTH_MAX 7
++/* only for ZSTD_btopt, other strategies are limited to 4 */
++#define ZSTD_SEARCHLENGTH_MIN 3
++#define ZSTD_TARGETLENGTH_MIN 4
++#define ZSTD_TARGETLENGTH_MAX 999
++
++/* for static allocation */
++#define ZSTD_FRAMEHEADERSIZE_MAX 18
++#define ZSTD_FRAMEHEADERSIZE_MIN 6
++static const size_t ZSTD_frameHeaderSize_prefix = 5;
++static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
++static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
++/* magic number + skippable frame length */
++static const size_t ZSTD_skippableHeaderSize = 8;
++
++
++/*-*************************************
++ * Compressed size functions
++ **************************************/
++
++/**
++ * ZSTD_findFrameCompressedSize() - returns the size of a compressed frame
++ * @src: Source buffer. It should point to the start of a zstd encoded frame
++ * or a skippable frame.
++ * @srcSize: The size of the source buffer. It must be at least as large as the
++ * size of the frame.
++ *
++ * Return: The compressed size of the frame pointed to by `src` or an error,
++ * which can be check with ZSTD_isError().
++ * Suitable to pass to ZSTD_decompress() or similar functions.
++ */
++size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize);
++
++/*-*************************************
++ * Decompressed size functions
++ **************************************/
++/**
++ * ZSTD_getFrameContentSize() - returns the content size in a zstd frame header
++ * @src: It should point to the start of a zstd encoded frame.
++ * @srcSize: The size of the source buffer. It must be at least as large as the
++ * frame header. `ZSTD_frameHeaderSize_max` is always large enough.
++ *
++ * Return: The frame content size stored in the frame header if known.
++ * `ZSTD_CONTENTSIZE_UNKNOWN` if the content size isn't stored in the
++ * frame header. `ZSTD_CONTENTSIZE_ERROR` on invalid input.
++ */
++unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
++
++/**
++ * ZSTD_findDecompressedSize() - returns decompressed size of a series of frames
++ * @src: It should point to the start of a series of zstd encoded and/or
++ * skippable frames.
++ * @srcSize: The exact size of the series of frames.
++ *
++ * If any zstd encoded frame in the series doesn't have the frame content size
++ * set, `ZSTD_CONTENTSIZE_UNKNOWN` is returned. But frame content size is always
++ * set when using ZSTD_compress(). The decompressed size can be very large.
++ * If the source is untrusted, the decompressed size could be wrong or
++ * intentionally modified. Always ensure the result fits within the
++ * application's authorized limits. ZSTD_findDecompressedSize() handles multiple
++ * frames, and so it must traverse the input to read each frame header. This is
++ * efficient as most of the data is skipped, however it does mean that all frame
++ * data must be present and valid.
++ *
++ * Return: Decompressed size of all the data contained in the frames if known.
++ * `ZSTD_CONTENTSIZE_UNKNOWN` if the decompressed size is unknown.
++ * `ZSTD_CONTENTSIZE_ERROR` if an error occurred.
++ */
++unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize);
++
++/*-*************************************
++ * Advanced compression functions
++ **************************************/
++/**
++ * ZSTD_checkCParams() - ensure parameter values remain within authorized range
++ * @cParams: The zstd compression parameters.
++ *
++ * Return: Zero or an error, which can be checked using ZSTD_isError().
++ */
++size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams);
++
++/**
++ * ZSTD_adjustCParams() - optimize parameters for a given srcSize and dictSize
++ * @srcSize: Optionally the estimated source size, or zero if unknown.
++ * @dictSize: Optionally the estimated dictionary size, or zero if unknown.
++ *
++ * Return: The optimized parameters.
++ */
++ZSTD_compressionParameters ZSTD_adjustCParams(
++ ZSTD_compressionParameters cParams, unsigned long long srcSize,
++ size_t dictSize);
++
++/*--- Advanced decompression functions ---*/
++
++/**
++ * ZSTD_isFrame() - returns true iff the buffer starts with a valid frame
++ * @buffer: The source buffer to check.
++ * @size: The size of the source buffer, must be at least 4 bytes.
++ *
++ * Return: True iff the buffer starts with a zstd or skippable frame identifier.
++ */
++unsigned int ZSTD_isFrame(const void *buffer, size_t size);
++
++/**
++ * ZSTD_getDictID_fromDict() - returns the dictionary id stored in a dictionary
++ * @dict: The dictionary buffer.
++ * @dictSize: The size of the dictionary buffer.
++ *
++ * Return: The dictionary id stored within the dictionary or 0 if the
++ * dictionary is not a zstd dictionary. If it returns 0 the
++ * dictionary can still be loaded as a content-only dictionary.
++ */
++unsigned int ZSTD_getDictID_fromDict(const void *dict, size_t dictSize);
++
++/**
++ * ZSTD_getDictID_fromDDict() - returns the dictionary id stored in a ZSTD_DDict
++ * @ddict: The ddict to find the id of.
++ *
++ * Return: The dictionary id stored within `ddict` or 0 if the dictionary is not
++ * a zstd dictionary. If it returns 0 `ddict` will be loaded as a
++ * content-only dictionary.
++ */
++unsigned int ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict);
++
++/**
++ * ZSTD_getDictID_fromFrame() - returns the dictionary id stored in a zstd frame
++ * @src: Source buffer. It must be a zstd encoded frame.
++ * @srcSize: The size of the source buffer. It must be at least as large as the
++ * frame header. `ZSTD_frameHeaderSize_max` is always large enough.
++ *
++ * Return: The dictionary id required to decompress the frame stored within
++ * `src` or 0 if the dictionary id could not be decoded. It can return
++ * 0 if the frame does not require a dictionary, the dictionary id
++ * wasn't stored in the frame, `src` is not a zstd frame, or `srcSize`
++ * is too small.
++ */
++unsigned int ZSTD_getDictID_fromFrame(const void *src, size_t srcSize);
++
++/**
++ * struct ZSTD_frameParams - zstd frame parameters stored in the frame header
++ * @frameContentSize: The frame content size, or 0 if not present.
++ * @windowSize: The window size, or 0 if the frame is a skippable frame.
++ * @dictID: The dictionary id, or 0 if not present.
++ * @checksumFlag: Whether a checksum was used.
++ */
++typedef struct {
++ unsigned long long frameContentSize;
++ unsigned int windowSize;
++ unsigned int dictID;
++ unsigned int checksumFlag;
++} ZSTD_frameParams;
++
++/**
++ * ZSTD_getFrameParams() - extracts parameters from a zstd or skippable frame
++ * @fparamsPtr: On success the frame parameters are written here.
++ * @src: The source buffer. It must point to a zstd or skippable frame.
++ * @srcSize: The size of the source buffer. `ZSTD_frameHeaderSize_max` is
++ * always large enough to succeed.
++ *
++ * Return: 0 on success. If more data is required it returns how many bytes
++ * must be provided to make forward progress. Otherwise it returns
++ * an error, which can be checked using ZSTD_isError().
++ */
++size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src,
++ size_t srcSize);
++
++/*-*****************************************************************************
++ * Buffer-less and synchronous inner streaming functions
++ *
++ * This is an advanced API, giving full control over buffer management, for
++ * users which need direct control over memory.
++ * But it's also a complex one, with many restrictions (documented below).
++ * Prefer using normal streaming API for an easier experience
++ ******************************************************************************/
++
++/*-*****************************************************************************
++ * Buffer-less streaming compression (synchronous mode)
++ *
++ * A ZSTD_CCtx object is required to track streaming operations.
++ * Use ZSTD_initCCtx() to initialize a context.
++ * ZSTD_CCtx object can be re-used multiple times within successive compression
++ * operations.
++ *
++ * Start by initializing a context.
++ * Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary
++ * compression,
++ * or ZSTD_compressBegin_advanced(), for finer parameter control.
++ * It's also possible to duplicate a reference context which has already been
++ * initialized, using ZSTD_copyCCtx()
++ *
++ * Then, consume your input using ZSTD_compressContinue().
++ * There are some important considerations to keep in mind when using this
++ * advanced function :
++ * - ZSTD_compressContinue() has no internal buffer. It uses externally provided
++ * buffer only.
++ * - Interface is synchronous : input is consumed entirely and produce 1+
++ * (or more) compressed blocks.
++ * - Caller must ensure there is enough space in `dst` to store compressed data
++ * under worst case scenario. Worst case evaluation is provided by
++ * ZSTD_compressBound().
++ * ZSTD_compressContinue() doesn't guarantee recover after a failed
++ * compression.
++ * - ZSTD_compressContinue() presumes prior input ***is still accessible and
++ * unmodified*** (up to maximum distance size, see WindowLog).
++ * It remembers all previous contiguous blocks, plus one separated memory
++ * segment (which can itself consists of multiple contiguous blocks)
++ * - ZSTD_compressContinue() detects that prior input has been overwritten when
++ * `src` buffer overlaps. In which case, it will "discard" the relevant memory
++ * section from its history.
++ *
++ * Finish a frame with ZSTD_compressEnd(), which will write the last block(s)
++ * and optional checksum. It's possible to use srcSize==0, in which case, it
++ * will write a final empty block to end the frame. Without last block mark,
++ * frames will be considered unfinished (corrupted) by decoders.
++ *
++ * `ZSTD_CCtx` object can be re-used (ZSTD_compressBegin()) to compress some new
++ * frame.
++ ******************************************************************************/
++
++/*===== Buffer-less streaming compression functions =====*/
++size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel);
++size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx *cctx, const void *dict,
++ size_t dictSize, int compressionLevel);
++size_t ZSTD_compressBegin_advanced(ZSTD_CCtx *cctx, const void *dict,
++ size_t dictSize, ZSTD_parameters params,
++ unsigned long long pledgedSrcSize);
++size_t ZSTD_copyCCtx(ZSTD_CCtx *cctx, const ZSTD_CCtx *preparedCCtx,
++ unsigned long long pledgedSrcSize);
++size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict,
++ unsigned long long pledgedSrcSize);
++size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize);
++size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize);
++
++
++
++/*-*****************************************************************************
++ * Buffer-less streaming decompression (synchronous mode)
++ *
++ * A ZSTD_DCtx object is required to track streaming operations.
++ * Use ZSTD_initDCtx() to initialize a context.
++ * A ZSTD_DCtx object can be re-used multiple times.
++ *
++ * First typical operation is to retrieve frame parameters, using
++ * ZSTD_getFrameParams(). It fills a ZSTD_frameParams structure which provide
++ * important information to correctly decode the frame, such as the minimum
++ * rolling buffer size to allocate to decompress data (`windowSize`), and the
++ * dictionary ID used.
++ * Note: content size is optional, it may not be present. 0 means unknown.
++ * Note that these values could be wrong, either because of data malformation,
++ * or because an attacker is spoofing deliberate false information. As a
++ * consequence, check that values remain within valid application range,
++ * especially `windowSize`, before allocation. Each application can set its own
++ * limit, depending on local restrictions. For extended interoperability, it is
++ * recommended to support at least 8 MB.
++ * Frame parameters are extracted from the beginning of the compressed frame.
++ * Data fragment must be large enough to ensure successful decoding, typically
++ * `ZSTD_frameHeaderSize_max` bytes.
++ * Result: 0: successful decoding, the `ZSTD_frameParams` structure is filled.
++ * >0: `srcSize` is too small, provide at least this many bytes.
++ * errorCode, which can be tested using ZSTD_isError().
++ *
++ * Start decompression, with ZSTD_decompressBegin() or
++ * ZSTD_decompressBegin_usingDict(). Alternatively, you can copy a prepared
++ * context, using ZSTD_copyDCtx().
++ *
++ * Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue()
++ * alternatively.
++ * ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize'
++ * to ZSTD_decompressContinue().
++ * ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will
++ * fail.
++ *
++ * The result of ZSTD_decompressContinue() is the number of bytes regenerated
++ * within 'dst' (necessarily <= dstCapacity). It can be zero, which is not an
++ * error; it just means ZSTD_decompressContinue() has decoded some metadata
++ * item. It can also be an error code, which can be tested with ZSTD_isError().
++ *
++ * ZSTD_decompressContinue() needs previous data blocks during decompression, up
++ * to `windowSize`. They should preferably be located contiguously, prior to
++ * current block. Alternatively, a round buffer of sufficient size is also
++ * possible. Sufficient size is determined by frame parameters.
++ * ZSTD_decompressContinue() is very sensitive to contiguity, if 2 blocks don't
++ * follow each other, make sure that either the compressor breaks contiguity at
++ * the same place, or that previous contiguous segment is large enough to
++ * properly handle maximum back-reference.
++ *
++ * A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
++ * Context can then be reset to start a new decompression.
++ *
++ * Note: it's possible to know if next input to present is a header or a block,
++ * using ZSTD_nextInputType(). This information is not required to properly
++ * decode a frame.
++ *
++ * == Special case: skippable frames ==
++ *
++ * Skippable frames allow integration of user-defined data into a flow of
++ * concatenated frames. Skippable frames will be ignored (skipped) by a
++ * decompressor. The format of skippable frames is as follows:
++ * a) Skippable frame ID - 4 Bytes, Little endian format, any value from
++ * 0x184D2A50 to 0x184D2A5F
++ * b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
++ * c) Frame Content - any content (User Data) of length equal to Frame Size
++ * For skippable frames ZSTD_decompressContinue() always returns 0.
++ * For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0
++ * what means that a frame is skippable.
++ * Note: If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might
++ * actually be a zstd encoded frame with no content. For purposes of
++ * decompression, it is valid in both cases to skip the frame using
++ * ZSTD_findFrameCompressedSize() to find its size in bytes.
++ * It also returns frame size as fparamsPtr->frameContentSize.
++ ******************************************************************************/
++
++/*===== Buffer-less streaming decompression functions =====*/
++size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx);
++size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict,
++ size_t dictSize);
++void ZSTD_copyDCtx(ZSTD_DCtx *dctx, const ZSTD_DCtx *preparedDCtx);
++size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx);
++size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize);
++typedef enum {
++ ZSTDnit_frameHeader,
++ ZSTDnit_blockHeader,
++ ZSTDnit_block,
++ ZSTDnit_lastBlock,
++ ZSTDnit_checksum,
++ ZSTDnit_skippableFrame
++} ZSTD_nextInputType_e;
++ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx);
++
++/*-*****************************************************************************
++ * Block functions
++ *
++ * Block functions produce and decode raw zstd blocks, without frame metadata.
++ * Frame metadata cost is typically ~18 bytes, which can be non-negligible for
++ * very small blocks (< 100 bytes). User will have to take in charge required
++ * information to regenerate data, such as compressed and content sizes.
++ *
++ * A few rules to respect:
++ * - Compressing and decompressing require a context structure
++ * + Use ZSTD_initCCtx() and ZSTD_initDCtx()
++ * - It is necessary to init context before starting
++ * + compression : ZSTD_compressBegin()
++ * + decompression : ZSTD_decompressBegin()
++ * + variants _usingDict() are also allowed
++ * + copyCCtx() and copyDCtx() work too
++ * - Block size is limited, it must be <= ZSTD_getBlockSizeMax()
++ * + If you need to compress more, cut data into multiple blocks
++ * + Consider using the regular ZSTD_compress() instead, as frame metadata
++ * costs become negligible when source size is large.
++ * - When a block is considered not compressible enough, ZSTD_compressBlock()
++ * result will be zero. In which case, nothing is produced into `dst`.
++ * + User must test for such outcome and deal directly with uncompressed data
++ * + ZSTD_decompressBlock() doesn't accept uncompressed data as input!!!
++ * + In case of multiple successive blocks, decoder must be informed of
++ * uncompressed block existence to follow proper history. Use
++ * ZSTD_insertBlock() in such a case.
++ ******************************************************************************/
++
++/* Define for static allocation */
++#define ZSTD_BLOCKSIZE_ABSOLUTEMAX (128 * 1024)
++/*===== Raw zstd block functions =====*/
++size_t ZSTD_getBlockSizeMax(ZSTD_CCtx *cctx);
++size_t ZSTD_compressBlock(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize);
++size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity,
++ const void *src, size_t srcSize);
++size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart,
++ size_t blockSize);
++
++#endif /* ZSTD_H */
+diff --git a/lib/Kconfig b/lib/Kconfig
+index 5e7541f..0d49ed0 100644
+--- a/lib/Kconfig
++++ b/lib/Kconfig
+@@ -249,6 +249,14 @@ config LZ4HC_COMPRESS
+ config LZ4_DECOMPRESS
+ tristate
+
++config ZSTD_COMPRESS
++ select XXHASH
++ tristate
++
++config ZSTD_DECOMPRESS
++ select XXHASH
++ tristate
++
+ source "lib/xz/Kconfig"
+
+ #
+diff --git a/lib/Makefile b/lib/Makefile
+index d06b68a..d5c8a4f 100644
+--- a/lib/Makefile
++++ b/lib/Makefile
+@@ -116,6 +116,8 @@ obj-$(CONFIG_LZO_DECOMPRESS) += lzo/
+ obj-$(CONFIG_LZ4_COMPRESS) += lz4/
+ obj-$(CONFIG_LZ4HC_COMPRESS) += lz4/
+ obj-$(CONFIG_LZ4_DECOMPRESS) += lz4/
++obj-$(CONFIG_ZSTD_COMPRESS) += zstd/
++obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd/
+ obj-$(CONFIG_XZ_DEC) += xz/
+ obj-$(CONFIG_RAID6_PQ) += raid6/
+
+diff --git a/lib/zstd/Makefile b/lib/zstd/Makefile
+new file mode 100644
+index 0000000..dd0a359
+--- /dev/null
++++ b/lib/zstd/Makefile
+@@ -0,0 +1,18 @@
++obj-$(CONFIG_ZSTD_COMPRESS) += zstd_compress.o
++obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd_decompress.o
++
++ccflags-y += -O3
++
++# Object files unique to zstd_compress and zstd_decompress
++zstd_compress-y := fse_compress.o huf_compress.o compress.o
++zstd_decompress-y := huf_decompress.o decompress.o
++
++# These object files are shared between the modules.
++# Always add them to zstd_compress.
++# Unless both zstd_compress and zstd_decompress are built in
++# then also add them to zstd_decompress.
++zstd_compress-y += entropy_common.o fse_decompress.o zstd_common.o
++
++ifneq ($(CONFIG_ZSTD_COMPRESS)$(CONFIG_ZSTD_DECOMPRESS),yy)
++ zstd_decompress-y += entropy_common.o fse_decompress.o zstd_common.o
++endif
+diff --git a/lib/zstd/bitstream.h b/lib/zstd/bitstream.h
+new file mode 100644
+index 0000000..a826b99
+--- /dev/null
++++ b/lib/zstd/bitstream.h
+@@ -0,0 +1,374 @@
++/*
++ * bitstream
++ * Part of FSE library
++ * header file (to include)
++ * Copyright (C) 2013-2016, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++#ifndef BITSTREAM_H_MODULE
++#define BITSTREAM_H_MODULE
++
++/*
++* This API consists of small unitary functions, which must be inlined for best performance.
++* Since link-time-optimization is not available for all compilers,
++* these functions are defined into a .h to be included.
++*/
++
++/*-****************************************
++* Dependencies
++******************************************/
++#include "error_private.h" /* error codes and messages */
++#include "mem.h" /* unaligned access routines */
++
++/*=========================================
++* Target specific
++=========================================*/
++#define STREAM_ACCUMULATOR_MIN_32 25
++#define STREAM_ACCUMULATOR_MIN_64 57
++#define STREAM_ACCUMULATOR_MIN ((U32)(ZSTD_32bits() ? STREAM_ACCUMULATOR_MIN_32 : STREAM_ACCUMULATOR_MIN_64))
++
++/*-******************************************
++* bitStream encoding API (write forward)
++********************************************/
++/* bitStream can mix input from multiple sources.
++* A critical property of these streams is that they encode and decode in **reverse** direction.
++* So the first bit sequence you add will be the last to be read, like a LIFO stack.
++*/
++typedef struct {
++ size_t bitContainer;
++ int bitPos;
++ char *startPtr;
++ char *ptr;
++ char *endPtr;
++} BIT_CStream_t;
++
++ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *dstBuffer, size_t dstCapacity);
++ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits);
++ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC);
++ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC);
++
++/* Start with initCStream, providing the size of buffer to write into.
++* bitStream will never write outside of this buffer.
++* `dstCapacity` must be >= sizeof(bitD->bitContainer), otherwise @return will be an error code.
++*
++* bits are first added to a local register.
++* Local register is size_t, hence 64-bits on 64-bits systems, or 32-bits on 32-bits systems.
++* Writing data into memory is an explicit operation, performed by the flushBits function.
++* Hence keep track how many bits are potentially stored into local register to avoid register overflow.
++* After a flushBits, a maximum of 7 bits might still be stored into local register.
++*
++* Avoid storing elements of more than 24 bits if you want compatibility with 32-bits bitstream readers.
++*
++* Last operation is to close the bitStream.
++* The function returns the final size of CStream in bytes.
++* If data couldn't fit into `dstBuffer`, it will return a 0 ( == not storable)
++*/
++
++/*-********************************************
++* bitStream decoding API (read backward)
++**********************************************/
++typedef struct {
++ size_t bitContainer;
++ unsigned bitsConsumed;
++ const char *ptr;
++ const char *start;
++} BIT_DStream_t;
++
++typedef enum {
++ BIT_DStream_unfinished = 0,
++ BIT_DStream_endOfBuffer = 1,
++ BIT_DStream_completed = 2,
++ BIT_DStream_overflow = 3
++} BIT_DStream_status; /* result of BIT_reloadDStream() */
++/* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */
++
++ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize);
++ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, unsigned nbBits);
++ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD);
++ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *bitD);
++
++/* Start by invoking BIT_initDStream().
++* A chunk of the bitStream is then stored into a local register.
++* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
++* You can then retrieve bitFields stored into the local register, **in reverse order**.
++* Local register is explicitly reloaded from memory by the BIT_reloadDStream() method.
++* A reload guarantee a minimum of ((8*sizeof(bitD->bitContainer))-7) bits when its result is BIT_DStream_unfinished.
++* Otherwise, it can be less than that, so proceed accordingly.
++* Checking if DStream has reached its end can be performed with BIT_endOfDStream().
++*/
++
++/*-****************************************
++* unsafe API
++******************************************/
++ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits);
++/* faster, but works only if value is "clean", meaning all high bits above nbBits are 0 */
++
++ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC);
++/* unsafe version; does not check buffer overflow */
++
++ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, unsigned nbBits);
++/* faster, but works only if nbBits >= 1 */
++
++/*-**************************************************************
++* Internal functions
++****************************************************************/
++ZSTD_STATIC unsigned BIT_highbit32(register U32 val) { return 31 - __builtin_clz(val); }
++
++/*===== Local Constants =====*/
++static const unsigned BIT_mask[] = {0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF,
++ 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF,
++ 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF}; /* up to 26 bits */
++
++/*-**************************************************************
++* bitStream encoding
++****************************************************************/
++/*! BIT_initCStream() :
++ * `dstCapacity` must be > sizeof(void*)
++ * @return : 0 if success,
++ otherwise an error code (can be tested using ERR_isError() ) */
++ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *startPtr, size_t dstCapacity)
++{
++ bitC->bitContainer = 0;
++ bitC->bitPos = 0;
++ bitC->startPtr = (char *)startPtr;
++ bitC->ptr = bitC->startPtr;
++ bitC->endPtr = bitC->startPtr + dstCapacity - sizeof(bitC->ptr);
++ if (dstCapacity <= sizeof(bitC->ptr))
++ return ERROR(dstSize_tooSmall);
++ return 0;
++}
++
++/*! BIT_addBits() :
++ can add up to 26 bits into `bitC`.
++ Does not check for register overflow ! */
++ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits)
++{
++ bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos;
++ bitC->bitPos += nbBits;
++}
++
++/*! BIT_addBitsFast() :
++ * works only if `value` is _clean_, meaning all high bits above nbBits are 0 */
++ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits)
++{
++ bitC->bitContainer |= value << bitC->bitPos;
++ bitC->bitPos += nbBits;
++}
++
++/*! BIT_flushBitsFast() :
++ * unsafe version; does not check buffer overflow */
++ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC)
++{
++ size_t const nbBytes = bitC->bitPos >> 3;
++ ZSTD_writeLEST(bitC->ptr, bitC->bitContainer);
++ bitC->ptr += nbBytes;
++ bitC->bitPos &= 7;
++ bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */
++}
++
++/*! BIT_flushBits() :
++ * safe version; check for buffer overflow, and prevents it.
++ * note : does not signal buffer overflow. This will be revealed later on using BIT_closeCStream() */
++ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC)
++{
++ size_t const nbBytes = bitC->bitPos >> 3;
++ ZSTD_writeLEST(bitC->ptr, bitC->bitContainer);
++ bitC->ptr += nbBytes;
++ if (bitC->ptr > bitC->endPtr)
++ bitC->ptr = bitC->endPtr;
++ bitC->bitPos &= 7;
++ bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */
++}
++
++/*! BIT_closeCStream() :
++ * @return : size of CStream, in bytes,
++ or 0 if it could not fit into dstBuffer */
++ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC)
++{
++ BIT_addBitsFast(bitC, 1, 1); /* endMark */
++ BIT_flushBits(bitC);
++
++ if (bitC->ptr >= bitC->endPtr)
++ return 0; /* doesn't fit within authorized budget : cancel */
++
++ return (bitC->ptr - bitC->startPtr) + (bitC->bitPos > 0);
++}
++
++/*-********************************************************
++* bitStream decoding
++**********************************************************/
++/*! BIT_initDStream() :
++* Initialize a BIT_DStream_t.
++* `bitD` : a pointer to an already allocated BIT_DStream_t structure.
++* `srcSize` must be the *exact* size of the bitStream, in bytes.
++* @return : size of stream (== srcSize) or an errorCode if a problem is detected
++*/
++ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize)
++{
++ if (srcSize < 1) {
++ memset(bitD, 0, sizeof(*bitD));
++ return ERROR(srcSize_wrong);
++ }
++
++ if (srcSize >= sizeof(bitD->bitContainer)) { /* normal case */
++ bitD->start = (const char *)srcBuffer;
++ bitD->ptr = (const char *)srcBuffer + srcSize - sizeof(bitD->bitContainer);
++ bitD->bitContainer = ZSTD_readLEST(bitD->ptr);
++ {
++ BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1];
++ bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; /* ensures bitsConsumed is always set */
++ if (lastByte == 0)
++ return ERROR(GENERIC); /* endMark not present */
++ }
++ } else {
++ bitD->start = (const char *)srcBuffer;
++ bitD->ptr = bitD->start;
++ bitD->bitContainer = *(const BYTE *)(bitD->start);
++ switch (srcSize) {
++ case 7: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[6]) << (sizeof(bitD->bitContainer) * 8 - 16);
++ case 6: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[5]) << (sizeof(bitD->bitContainer) * 8 - 24);
++ case 5: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[4]) << (sizeof(bitD->bitContainer) * 8 - 32);
++ case 4: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[3]) << 24;
++ case 3: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[2]) << 16;
++ case 2: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[1]) << 8;
++ default:;
++ }
++ {
++ BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1];
++ bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0;
++ if (lastByte == 0)
++ return ERROR(GENERIC); /* endMark not present */
++ }
++ bitD->bitsConsumed += (U32)(sizeof(bitD->bitContainer) - srcSize) * 8;
++ }
++
++ return srcSize;
++}
++
++ZSTD_STATIC size_t BIT_getUpperBits(size_t bitContainer, U32 const start) { return bitContainer >> start; }
++
++ZSTD_STATIC size_t BIT_getMiddleBits(size_t bitContainer, U32 const start, U32 const nbBits) { return (bitContainer >> start) & BIT_mask[nbBits]; }
++
++ZSTD_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits) { return bitContainer & BIT_mask[nbBits]; }
++
++/*! BIT_lookBits() :
++ * Provides next n bits from local register.
++ * local register is not modified.
++ * On 32-bits, maxNbBits==24.
++ * On 64-bits, maxNbBits==56.
++ * @return : value extracted
++ */
++ZSTD_STATIC size_t BIT_lookBits(const BIT_DStream_t *bitD, U32 nbBits)
++{
++ U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1;
++ return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask - nbBits) & bitMask);
++}
++
++/*! BIT_lookBitsFast() :
++* unsafe version; only works only if nbBits >= 1 */
++ZSTD_STATIC size_t BIT_lookBitsFast(const BIT_DStream_t *bitD, U32 nbBits)
++{
++ U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1;
++ return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask + 1) - nbBits) & bitMask);
++}
++
++ZSTD_STATIC void BIT_skipBits(BIT_DStream_t *bitD, U32 nbBits) { bitD->bitsConsumed += nbBits; }
++
++/*! BIT_readBits() :
++ * Read (consume) next n bits from local register and update.
++ * Pay attention to not read more than nbBits contained into local register.
++ * @return : extracted value.
++ */
++ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, U32 nbBits)
++{
++ size_t const value = BIT_lookBits(bitD, nbBits);
++ BIT_skipBits(bitD, nbBits);
++ return value;
++}
++
++/*! BIT_readBitsFast() :
++* unsafe version; only works only if nbBits >= 1 */
++ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, U32 nbBits)
++{
++ size_t const value = BIT_lookBitsFast(bitD, nbBits);
++ BIT_skipBits(bitD, nbBits);
++ return value;
++}
++
++/*! BIT_reloadDStream() :
++* Refill `bitD` from buffer previously set in BIT_initDStream() .
++* This function is safe, it guarantees it will not read beyond src buffer.
++* @return : status of `BIT_DStream_t` internal register.
++ if status == BIT_DStream_unfinished, internal register is filled with >= (sizeof(bitD->bitContainer)*8 - 7) bits */
++ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD)
++{
++ if (bitD->bitsConsumed > (sizeof(bitD->bitContainer) * 8)) /* should not happen => corruption detected */
++ return BIT_DStream_overflow;
++
++ if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) {
++ bitD->ptr -= bitD->bitsConsumed >> 3;
++ bitD->bitsConsumed &= 7;
++ bitD->bitContainer = ZSTD_readLEST(bitD->ptr);
++ return BIT_DStream_unfinished;
++ }
++ if (bitD->ptr == bitD->start) {
++ if (bitD->bitsConsumed < sizeof(bitD->bitContainer) * 8)
++ return BIT_DStream_endOfBuffer;
++ return BIT_DStream_completed;
++ }
++ {
++ U32 nbBytes = bitD->bitsConsumed >> 3;
++ BIT_DStream_status result = BIT_DStream_unfinished;
++ if (bitD->ptr - nbBytes < bitD->start) {
++ nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */
++ result = BIT_DStream_endOfBuffer;
++ }
++ bitD->ptr -= nbBytes;
++ bitD->bitsConsumed -= nbBytes * 8;
++ bitD->bitContainer = ZSTD_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */
++ return result;
++ }
++}
++
++/*! BIT_endOfDStream() :
++* @return Tells if DStream has exactly reached its end (all bits consumed).
++*/
++ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *DStream)
++{
++ return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer) * 8));
++}
++
++#endif /* BITSTREAM_H_MODULE */
+diff --git a/lib/zstd/compress.c b/lib/zstd/compress.c
+new file mode 100644
+index 0000000..ff18ae6
+--- /dev/null
++++ b/lib/zstd/compress.c
+@@ -0,0 +1,3482 @@
++/**
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++/*-*************************************
++* Dependencies
++***************************************/
++#include "fse.h"
++#include "huf.h"
++#include "mem.h"
++#include "zstd_internal.h" /* includes zstd.h */
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/string.h> /* memset */
++
++/*-*************************************
++* Constants
++***************************************/
++static const U32 g_searchStrength = 8; /* control skip over incompressible data */
++#define HASH_READ_SIZE 8
++typedef enum { ZSTDcs_created = 0, ZSTDcs_init, ZSTDcs_ongoing, ZSTDcs_ending } ZSTD_compressionStage_e;
++
++/*-*************************************
++* Helper functions
++***************************************/
++size_t ZSTD_compressBound(size_t srcSize) { return FSE_compressBound(srcSize) + 12; }
++
++/*-*************************************
++* Sequence storage
++***************************************/
++static void ZSTD_resetSeqStore(seqStore_t *ssPtr)
++{
++ ssPtr->lit = ssPtr->litStart;
++ ssPtr->sequences = ssPtr->sequencesStart;
++ ssPtr->longLengthID = 0;
++}
++
++/*-*************************************
++* Context memory management
++***************************************/
++struct ZSTD_CCtx_s {
++ const BYTE *nextSrc; /* next block here to continue on curr prefix */
++ const BYTE *base; /* All regular indexes relative to this position */
++ const BYTE *dictBase; /* extDict indexes relative to this position */
++ U32 dictLimit; /* below that point, need extDict */
++ U32 lowLimit; /* below that point, no more data */
++ U32 nextToUpdate; /* index from which to continue dictionary update */
++ U32 nextToUpdate3; /* index from which to continue dictionary update */
++ U32 hashLog3; /* dispatch table : larger == faster, more memory */
++ U32 loadedDictEnd; /* index of end of dictionary */
++ U32 forceWindow; /* force back-references to respect limit of 1<<wLog, even for dictionary */
++ U32 forceRawDict; /* Force loading dictionary in "content-only" mode (no header analysis) */
++ ZSTD_compressionStage_e stage;
++ U32 rep[ZSTD_REP_NUM];
++ U32 repToConfirm[ZSTD_REP_NUM];
++ U32 dictID;
++ ZSTD_parameters params;
++ void *workSpace;
++ size_t workSpaceSize;
++ size_t blockSize;
++ U64 frameContentSize;
++ struct xxh64_state xxhState;
++ ZSTD_customMem customMem;
++
++ seqStore_t seqStore; /* sequences storage ptrs */
++ U32 *hashTable;
++ U32 *hashTable3;
++ U32 *chainTable;
++ HUF_CElt *hufTable;
++ U32 flagStaticTables;
++ HUF_repeat flagStaticHufTable;
++ FSE_CTable offcodeCTable[FSE_CTABLE_SIZE_U32(OffFSELog, MaxOff)];
++ FSE_CTable matchlengthCTable[FSE_CTABLE_SIZE_U32(MLFSELog, MaxML)];
++ FSE_CTable litlengthCTable[FSE_CTABLE_SIZE_U32(LLFSELog, MaxLL)];
++ unsigned tmpCounters[HUF_COMPRESS_WORKSPACE_SIZE_U32];
++};
++
++size_t ZSTD_CCtxWorkspaceBound(ZSTD_compressionParameters cParams)
++{
++ size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog);
++ U32 const divider = (cParams.searchLength == 3) ? 3 : 4;
++ size_t const maxNbSeq = blockSize / divider;
++ size_t const tokenSpace = blockSize + 11 * maxNbSeq;
++ size_t const chainSize = (cParams.strategy == ZSTD_fast) ? 0 : (1 << cParams.chainLog);
++ size_t const hSize = ((size_t)1) << cParams.hashLog;
++ U32 const hashLog3 = (cParams.searchLength > 3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, cParams.windowLog);
++ size_t const h3Size = ((size_t)1) << hashLog3;
++ size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
++ size_t const optSpace =
++ ((MaxML + 1) + (MaxLL + 1) + (MaxOff + 1) + (1 << Litbits)) * sizeof(U32) + (ZSTD_OPT_NUM + 1) * (sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
++ size_t const workspaceSize = tableSpace + (256 * sizeof(U32)) /* huffTable */ + tokenSpace +
++ (((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optSpace : 0);
++
++ return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_CCtx)) + ZSTD_ALIGN(workspaceSize);
++}
++
++static ZSTD_CCtx *ZSTD_createCCtx_advanced(ZSTD_customMem customMem)
++{
++ ZSTD_CCtx *cctx;
++ if (!customMem.customAlloc || !customMem.customFree)
++ return NULL;
++ cctx = (ZSTD_CCtx *)ZSTD_malloc(sizeof(ZSTD_CCtx), customMem);
++ if (!cctx)
++ return NULL;
++ memset(cctx, 0, sizeof(ZSTD_CCtx));
++ cctx->customMem = customMem;
++ return cctx;
++}
++
++ZSTD_CCtx *ZSTD_initCCtx(void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
++ ZSTD_CCtx *cctx = ZSTD_createCCtx_advanced(stackMem);
++ if (cctx) {
++ cctx->workSpace = ZSTD_stackAllocAll(cctx->customMem.opaque, &cctx->workSpaceSize);
++ }
++ return cctx;
++}
++
++size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx)
++{
++ if (cctx == NULL)
++ return 0; /* support free on NULL */
++ ZSTD_free(cctx->workSpace, cctx->customMem);
++ ZSTD_free(cctx, cctx->customMem);
++ return 0; /* reserved as a potential error code in the future */
++}
++
++const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx) /* hidden interface */ { return &(ctx->seqStore); }
++
++static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx *cctx) { return cctx->params; }
++
++/** ZSTD_checkParams() :
++ ensure param values remain within authorized range.
++ @return : 0, or an error code if one value is beyond authorized range */
++size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams)
++{
++#define CLAMPCHECK(val, min, max) \
++ { \
++ if ((val < min) | (val > max)) \
++ return ERROR(compressionParameter_unsupported); \
++ }
++ CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
++ CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
++ CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
++ CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
++ CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
++ CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
++ if ((U32)(cParams.strategy) > (U32)ZSTD_btopt2)
++ return ERROR(compressionParameter_unsupported);
++ return 0;
++}
++
++/** ZSTD_cycleLog() :
++ * condition for correct operation : hashLog > 1 */
++static U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat)
++{
++ U32 const btScale = ((U32)strat >= (U32)ZSTD_btlazy2);
++ return hashLog - btScale;
++}
++
++/** ZSTD_adjustCParams() :
++ optimize `cPar` for a given input (`srcSize` and `dictSize`).
++ mostly downsizing to reduce memory consumption and initialization.
++ Both `srcSize` and `dictSize` are optional (use 0 if unknown),
++ but if both are 0, no optimization can be done.
++ Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */
++ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
++{
++ if (srcSize + dictSize == 0)
++ return cPar; /* no size information available : no adjustment */
++
++ /* resize params, to use less memory when necessary */
++ {
++ U32 const minSrcSize = (srcSize == 0) ? 500 : 0;
++ U64 const rSize = srcSize + dictSize + minSrcSize;
++ if (rSize < ((U64)1 << ZSTD_WINDOWLOG_MAX)) {
++ U32 const srcLog = MAX(ZSTD_HASHLOG_MIN, ZSTD_highbit32((U32)(rSize)-1) + 1);
++ if (cPar.windowLog > srcLog)
++ cPar.windowLog = srcLog;
++ }
++ }
++ if (cPar.hashLog > cPar.windowLog)
++ cPar.hashLog = cPar.windowLog;
++ {
++ U32 const cycleLog = ZSTD_cycleLog(cPar.chainLog, cPar.strategy);
++ if (cycleLog > cPar.windowLog)
++ cPar.chainLog -= (cycleLog - cPar.windowLog);
++ }
++
++ if (cPar.windowLog < ZSTD_WINDOWLOG_ABSOLUTEMIN)
++ cPar.windowLog = ZSTD_WINDOWLOG_ABSOLUTEMIN; /* required for frame header */
++
++ return cPar;
++}
++
++static U32 ZSTD_equivalentParams(ZSTD_parameters param1, ZSTD_parameters param2)
++{
++ return (param1.cParams.hashLog == param2.cParams.hashLog) & (param1.cParams.chainLog == param2.cParams.chainLog) &
++ (param1.cParams.strategy == param2.cParams.strategy) & ((param1.cParams.searchLength == 3) == (param2.cParams.searchLength == 3));
++}
++
++/*! ZSTD_continueCCtx() :
++ reuse CCtx without reset (note : requires no dictionary) */
++static size_t ZSTD_continueCCtx(ZSTD_CCtx *cctx, ZSTD_parameters params, U64 frameContentSize)
++{
++ U32 const end = (U32)(cctx->nextSrc - cctx->base);
++ cctx->params = params;
++ cctx->frameContentSize = frameContentSize;
++ cctx->lowLimit = end;
++ cctx->dictLimit = end;
++ cctx->nextToUpdate = end + 1;
++ cctx->stage = ZSTDcs_init;
++ cctx->dictID = 0;
++ cctx->loadedDictEnd = 0;
++ {
++ int i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ cctx->rep[i] = repStartValue[i];
++ }
++ cctx->seqStore.litLengthSum = 0; /* force reset of btopt stats */
++ xxh64_reset(&cctx->xxhState, 0);
++ return 0;
++}
++
++typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset, ZSTDcrp_fullReset } ZSTD_compResetPolicy_e;
++
++/*! ZSTD_resetCCtx_advanced() :
++ note : `params` must be validated */
++static size_t ZSTD_resetCCtx_advanced(ZSTD_CCtx *zc, ZSTD_parameters params, U64 frameContentSize, ZSTD_compResetPolicy_e const crp)
++{
++ if (crp == ZSTDcrp_continue)
++ if (ZSTD_equivalentParams(params, zc->params)) {
++ zc->flagStaticTables = 0;
++ zc->flagStaticHufTable = HUF_repeat_none;
++ return ZSTD_continueCCtx(zc, params, frameContentSize);
++ }
++
++ {
++ size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog);
++ U32 const divider = (params.cParams.searchLength == 3) ? 3 : 4;
++ size_t const maxNbSeq = blockSize / divider;
++ size_t const tokenSpace = blockSize + 11 * maxNbSeq;
++ size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ? 0 : (1 << params.cParams.chainLog);
++ size_t const hSize = ((size_t)1) << params.cParams.hashLog;
++ U32 const hashLog3 = (params.cParams.searchLength > 3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
++ size_t const h3Size = ((size_t)1) << hashLog3;
++ size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
++ void *ptr;
++
++ /* Check if workSpace is large enough, alloc a new one if needed */
++ {
++ size_t const optSpace = ((MaxML + 1) + (MaxLL + 1) + (MaxOff + 1) + (1 << Litbits)) * sizeof(U32) +
++ (ZSTD_OPT_NUM + 1) * (sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
++ size_t const neededSpace = tableSpace + (256 * sizeof(U32)) /* huffTable */ + tokenSpace +
++ (((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) ? optSpace : 0);
++ if (zc->workSpaceSize < neededSpace) {
++ ZSTD_free(zc->workSpace, zc->customMem);
++ zc->workSpace = ZSTD_malloc(neededSpace, zc->customMem);
++ if (zc->workSpace == NULL)
++ return ERROR(memory_allocation);
++ zc->workSpaceSize = neededSpace;
++ }
++ }
++
++ if (crp != ZSTDcrp_noMemset)
++ memset(zc->workSpace, 0, tableSpace); /* reset tables only */
++ xxh64_reset(&zc->xxhState, 0);
++ zc->hashLog3 = hashLog3;
++ zc->hashTable = (U32 *)(zc->workSpace);
++ zc->chainTable = zc->hashTable + hSize;
++ zc->hashTable3 = zc->chainTable + chainSize;
++ ptr = zc->hashTable3 + h3Size;
++ zc->hufTable = (HUF_CElt *)ptr;
++ zc->flagStaticTables = 0;
++ zc->flagStaticHufTable = HUF_repeat_none;
++ ptr = ((U32 *)ptr) + 256; /* note : HUF_CElt* is incomplete type, size is simulated using U32 */
++
++ zc->nextToUpdate = 1;
++ zc->nextSrc = NULL;
++ zc->base = NULL;
++ zc->dictBase = NULL;
++ zc->dictLimit = 0;
++ zc->lowLimit = 0;
++ zc->params = params;
++ zc->blockSize = blockSize;
++ zc->frameContentSize = frameContentSize;
++ {
++ int i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ zc->rep[i] = repStartValue[i];
++ }
++
++ if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) {
++ zc->seqStore.litFreq = (U32 *)ptr;
++ zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1 << Litbits);
++ zc->seqStore.matchLengthFreq = zc->seqStore.litLengthFreq + (MaxLL + 1);
++ zc->seqStore.offCodeFreq = zc->seqStore.matchLengthFreq + (MaxML + 1);
++ ptr = zc->seqStore.offCodeFreq + (MaxOff + 1);
++ zc->seqStore.matchTable = (ZSTD_match_t *)ptr;
++ ptr = zc->seqStore.matchTable + ZSTD_OPT_NUM + 1;
++ zc->seqStore.priceTable = (ZSTD_optimal_t *)ptr;
++ ptr = zc->seqStore.priceTable + ZSTD_OPT_NUM + 1;
++ zc->seqStore.litLengthSum = 0;
++ }
++ zc->seqStore.sequencesStart = (seqDef *)ptr;
++ ptr = zc->seqStore.sequencesStart + maxNbSeq;
++ zc->seqStore.llCode = (BYTE *)ptr;
++ zc->seqStore.mlCode = zc->seqStore.llCode + maxNbSeq;
++ zc->seqStore.ofCode = zc->seqStore.mlCode + maxNbSeq;
++ zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq;
++
++ zc->stage = ZSTDcs_init;
++ zc->dictID = 0;
++ zc->loadedDictEnd = 0;
++
++ return 0;
++ }
++}
++
++/* ZSTD_invalidateRepCodes() :
++ * ensures next compression will not use repcodes from previous block.
++ * Note : only works with regular variant;
++ * do not use with extDict variant ! */
++void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx)
++{
++ int i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ cctx->rep[i] = 0;
++}
++
++/*! ZSTD_copyCCtx() :
++* Duplicate an existing context `srcCCtx` into another one `dstCCtx`.
++* Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
++* @return : 0, or an error code */
++size_t ZSTD_copyCCtx(ZSTD_CCtx *dstCCtx, const ZSTD_CCtx *srcCCtx, unsigned long long pledgedSrcSize)
++{
++ if (srcCCtx->stage != ZSTDcs_init)
++ return ERROR(stage_wrong);
++
++ memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem));
++ {
++ ZSTD_parameters params = srcCCtx->params;
++ params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
++ ZSTD_resetCCtx_advanced(dstCCtx, params, pledgedSrcSize, ZSTDcrp_noMemset);
++ }
++
++ /* copy tables */
++ {
++ size_t const chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog);
++ size_t const hSize = ((size_t)1) << srcCCtx->params.cParams.hashLog;
++ size_t const h3Size = (size_t)1 << srcCCtx->hashLog3;
++ size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
++ memcpy(dstCCtx->workSpace, srcCCtx->workSpace, tableSpace);
++ }
++
++ /* copy dictionary offsets */
++ dstCCtx->nextToUpdate = srcCCtx->nextToUpdate;
++ dstCCtx->nextToUpdate3 = srcCCtx->nextToUpdate3;
++ dstCCtx->nextSrc = srcCCtx->nextSrc;
++ dstCCtx->base = srcCCtx->base;
++ dstCCtx->dictBase = srcCCtx->dictBase;
++ dstCCtx->dictLimit = srcCCtx->dictLimit;
++ dstCCtx->lowLimit = srcCCtx->lowLimit;
++ dstCCtx->loadedDictEnd = srcCCtx->loadedDictEnd;
++ dstCCtx->dictID = srcCCtx->dictID;
++
++ /* copy entropy tables */
++ dstCCtx->flagStaticTables = srcCCtx->flagStaticTables;
++ dstCCtx->flagStaticHufTable = srcCCtx->flagStaticHufTable;
++ if (srcCCtx->flagStaticTables) {
++ memcpy(dstCCtx->litlengthCTable, srcCCtx->litlengthCTable, sizeof(dstCCtx->litlengthCTable));
++ memcpy(dstCCtx->matchlengthCTable, srcCCtx->matchlengthCTable, sizeof(dstCCtx->matchlengthCTable));
++ memcpy(dstCCtx->offcodeCTable, srcCCtx->offcodeCTable, sizeof(dstCCtx->offcodeCTable));
++ }
++ if (srcCCtx->flagStaticHufTable) {
++ memcpy(dstCCtx->hufTable, srcCCtx->hufTable, 256 * 4);
++ }
++
++ return 0;
++}
++
++/*! ZSTD_reduceTable() :
++* reduce table indexes by `reducerValue` */
++static void ZSTD_reduceTable(U32 *const table, U32 const size, U32 const reducerValue)
++{
++ U32 u;
++ for (u = 0; u < size; u++) {
++ if (table[u] < reducerValue)
++ table[u] = 0;
++ else
++ table[u] -= reducerValue;
++ }
++}
++
++/*! ZSTD_reduceIndex() :
++* rescale all indexes to avoid future overflow (indexes are U32) */
++static void ZSTD_reduceIndex(ZSTD_CCtx *zc, const U32 reducerValue)
++{
++ {
++ U32 const hSize = 1 << zc->params.cParams.hashLog;
++ ZSTD_reduceTable(zc->hashTable, hSize, reducerValue);
++ }
++
++ {
++ U32 const chainSize = (zc->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->params.cParams.chainLog);
++ ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue);
++ }
++
++ {
++ U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0;
++ ZSTD_reduceTable(zc->hashTable3, h3Size, reducerValue);
++ }
++}
++
++/*-*******************************************************
++* Block entropic compression
++*********************************************************/
++
++/* See doc/zstd_compression_format.md for detailed format description */
++
++size_t ZSTD_noCompressBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ if (srcSize + ZSTD_blockHeaderSize > dstCapacity)
++ return ERROR(dstSize_tooSmall);
++ memcpy((BYTE *)dst + ZSTD_blockHeaderSize, src, srcSize);
++ ZSTD_writeLE24(dst, (U32)(srcSize << 2) + (U32)bt_raw);
++ return ZSTD_blockHeaderSize + srcSize;
++}
++
++static size_t ZSTD_noCompressLiterals(void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ BYTE *const ostart = (BYTE * const)dst;
++ U32 const flSize = 1 + (srcSize > 31) + (srcSize > 4095);
++
++ if (srcSize + flSize > dstCapacity)
++ return ERROR(dstSize_tooSmall);
++
++ switch (flSize) {
++ case 1: /* 2 - 1 - 5 */ ostart[0] = (BYTE)((U32)set_basic + (srcSize << 3)); break;
++ case 2: /* 2 - 2 - 12 */ ZSTD_writeLE16(ostart, (U16)((U32)set_basic + (1 << 2) + (srcSize << 4))); break;
++ default: /*note : should not be necessary : flSize is within {1,2,3} */
++ case 3: /* 2 - 2 - 20 */ ZSTD_writeLE32(ostart, (U32)((U32)set_basic + (3 << 2) + (srcSize << 4))); break;
++ }
++
++ memcpy(ostart + flSize, src, srcSize);
++ return srcSize + flSize;
++}
++
++static size_t ZSTD_compressRleLiteralsBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ BYTE *const ostart = (BYTE * const)dst;
++ U32 const flSize = 1 + (srcSize > 31) + (srcSize > 4095);
++
++ (void)dstCapacity; /* dstCapacity already guaranteed to be >=4, hence large enough */
++
++ switch (flSize) {
++ case 1: /* 2 - 1 - 5 */ ostart[0] = (BYTE)((U32)set_rle + (srcSize << 3)); break;
++ case 2: /* 2 - 2 - 12 */ ZSTD_writeLE16(ostart, (U16)((U32)set_rle + (1 << 2) + (srcSize << 4))); break;
++ default: /*note : should not be necessary : flSize is necessarily within {1,2,3} */
++ case 3: /* 2 - 2 - 20 */ ZSTD_writeLE32(ostart, (U32)((U32)set_rle + (3 << 2) + (srcSize << 4))); break;
++ }
++
++ ostart[flSize] = *(const BYTE *)src;
++ return flSize + 1;
++}
++
++static size_t ZSTD_minGain(size_t srcSize) { return (srcSize >> 6) + 2; }
++
++static size_t ZSTD_compressLiterals(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ size_t const minGain = ZSTD_minGain(srcSize);
++ size_t const lhSize = 3 + (srcSize >= 1 KB) + (srcSize >= 16 KB);
++ BYTE *const ostart = (BYTE *)dst;
++ U32 singleStream = srcSize < 256;
++ symbolEncodingType_e hType = set_compressed;
++ size_t cLitSize;
++
++/* small ? don't even attempt compression (speed opt) */
++#define LITERAL_NOENTROPY 63
++ {
++ size_t const minLitSize = zc->flagStaticHufTable == HUF_repeat_valid ? 6 : LITERAL_NOENTROPY;
++ if (srcSize <= minLitSize)
++ return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize);
++ }
++
++ if (dstCapacity < lhSize + 1)
++ return ERROR(dstSize_tooSmall); /* not enough space for compression */
++ {
++ HUF_repeat repeat = zc->flagStaticHufTable;
++ int const preferRepeat = zc->params.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
++ if (repeat == HUF_repeat_valid && lhSize == 3)
++ singleStream = 1;
++ cLitSize = singleStream ? HUF_compress1X_repeat(ostart + lhSize, dstCapacity - lhSize, src, srcSize, 255, 11, zc->tmpCounters,
++ sizeof(zc->tmpCounters), zc->hufTable, &repeat, preferRepeat)
++ : HUF_compress4X_repeat(ostart + lhSize, dstCapacity - lhSize, src, srcSize, 255, 11, zc->tmpCounters,
++ sizeof(zc->tmpCounters), zc->hufTable, &repeat, preferRepeat);
++ if (repeat != HUF_repeat_none) {
++ hType = set_repeat;
++ } /* reused the existing table */
++ else {
++ zc->flagStaticHufTable = HUF_repeat_check;
++ } /* now have a table to reuse */
++ }
++
++ if ((cLitSize == 0) | (cLitSize >= srcSize - minGain)) {
++ zc->flagStaticHufTable = HUF_repeat_none;
++ return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize);
++ }
++ if (cLitSize == 1) {
++ zc->flagStaticHufTable = HUF_repeat_none;
++ return ZSTD_compressRleLiteralsBlock(dst, dstCapacity, src, srcSize);
++ }
++
++ /* Build header */
++ switch (lhSize) {
++ case 3: /* 2 - 2 - 10 - 10 */
++ {
++ U32 const lhc = hType + ((!singleStream) << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 14);
++ ZSTD_writeLE24(ostart, lhc);
++ break;
++ }
++ case 4: /* 2 - 2 - 14 - 14 */
++ {
++ U32 const lhc = hType + (2 << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 18);
++ ZSTD_writeLE32(ostart, lhc);
++ break;
++ }
++ default: /* should not be necessary, lhSize is only {3,4,5} */
++ case 5: /* 2 - 2 - 18 - 18 */
++ {
++ U32 const lhc = hType + (3 << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 22);
++ ZSTD_writeLE32(ostart, lhc);
++ ostart[4] = (BYTE)(cLitSize >> 10);
++ break;
++ }
++ }
++ return lhSize + cLitSize;
++}
++
++static const BYTE LL_Code[64] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 16, 17, 17, 18, 18,
++ 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23,
++ 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24};
++
++static const BYTE ML_Code[128] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,
++ 26, 27, 28, 29, 30, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 36, 36, 37, 37, 37, 37, 38, 38, 38, 38,
++ 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
++ 40, 40, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 42, 42, 42, 42, 42, 42, 42, 42,
++ 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42};
++
++void ZSTD_seqToCodes(const seqStore_t *seqStorePtr)
++{
++ BYTE const LL_deltaCode = 19;
++ BYTE const ML_deltaCode = 36;
++ const seqDef *const sequences = seqStorePtr->sequencesStart;
++ BYTE *const llCodeTable = seqStorePtr->llCode;
++ BYTE *const ofCodeTable = seqStorePtr->ofCode;
++ BYTE *const mlCodeTable = seqStorePtr->mlCode;
++ U32 const nbSeq = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
++ U32 u;
++ for (u = 0; u < nbSeq; u++) {
++ U32 const llv = sequences[u].litLength;
++ U32 const mlv = sequences[u].matchLength;
++ llCodeTable[u] = (llv > 63) ? (BYTE)ZSTD_highbit32(llv) + LL_deltaCode : LL_Code[llv];
++ ofCodeTable[u] = (BYTE)ZSTD_highbit32(sequences[u].offset);
++ mlCodeTable[u] = (mlv > 127) ? (BYTE)ZSTD_highbit32(mlv) + ML_deltaCode : ML_Code[mlv];
++ }
++ if (seqStorePtr->longLengthID == 1)
++ llCodeTable[seqStorePtr->longLengthPos] = MaxLL;
++ if (seqStorePtr->longLengthID == 2)
++ mlCodeTable[seqStorePtr->longLengthPos] = MaxML;
++}
++
++ZSTD_STATIC size_t ZSTD_compressSequences_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity)
++{
++ const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
++ const seqStore_t *seqStorePtr = &(zc->seqStore);
++ FSE_CTable *CTable_LitLength = zc->litlengthCTable;
++ FSE_CTable *CTable_OffsetBits = zc->offcodeCTable;
++ FSE_CTable *CTable_MatchLength = zc->matchlengthCTable;
++ U32 LLtype, Offtype, MLtype; /* compressed, raw or rle */
++ const seqDef *const sequences = seqStorePtr->sequencesStart;
++ const BYTE *const ofCodeTable = seqStorePtr->ofCode;
++ const BYTE *const llCodeTable = seqStorePtr->llCode;
++ const BYTE *const mlCodeTable = seqStorePtr->mlCode;
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstCapacity;
++ BYTE *op = ostart;
++ size_t const nbSeq = seqStorePtr->sequences - seqStorePtr->sequencesStart;
++ BYTE *seqHead;
++
++ U32 *count;
++ S16 *norm;
++ U32 *workspace;
++ size_t workspaceSize = sizeof(zc->tmpCounters);
++ {
++ size_t spaceUsed32 = 0;
++ count = (U32 *)zc->tmpCounters + spaceUsed32;
++ spaceUsed32 += MaxSeq + 1;
++ norm = (S16 *)((U32 *)zc->tmpCounters + spaceUsed32);
++ spaceUsed32 += ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2;
++
++ workspace = (U32 *)zc->tmpCounters + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++ }
++
++ /* Compress literals */
++ {
++ const BYTE *const literals = seqStorePtr->litStart;
++ size_t const litSize = seqStorePtr->lit - literals;
++ size_t const cSize = ZSTD_compressLiterals(zc, op, dstCapacity, literals, litSize);
++ if (ZSTD_isError(cSize))
++ return cSize;
++ op += cSize;
++ }
++
++ /* Sequences Header */
++ if ((oend - op) < 3 /*max nbSeq Size*/ + 1 /*seqHead */)
++ return ERROR(dstSize_tooSmall);
++ if (nbSeq < 0x7F)
++ *op++ = (BYTE)nbSeq;
++ else if (nbSeq < LONGNBSEQ)
++ op[0] = (BYTE)((nbSeq >> 8) + 0x80), op[1] = (BYTE)nbSeq, op += 2;
++ else
++ op[0] = 0xFF, ZSTD_writeLE16(op + 1, (U16)(nbSeq - LONGNBSEQ)), op += 3;
++ if (nbSeq == 0)
++ return op - ostart;
++
++ /* seqHead : flags for FSE encoding type */
++ seqHead = op++;
++
++#define MIN_SEQ_FOR_DYNAMIC_FSE 64
++#define MAX_SEQ_FOR_STATIC_FSE 1000
++
++ /* convert length/distances into codes */
++ ZSTD_seqToCodes(seqStorePtr);
++
++ /* CTable for Literal Lengths */
++ {
++ U32 max = MaxLL;
++ size_t const mostFrequent = FSE_countFast_wksp(count, &max, llCodeTable, nbSeq, workspace);
++ if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
++ *op++ = llCodeTable[0];
++ FSE_buildCTable_rle(CTable_LitLength, (BYTE)max);
++ LLtype = set_rle;
++ } else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
++ LLtype = set_repeat;
++ } else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (LL_defaultNormLog - 1)))) {
++ FSE_buildCTable_wksp(CTable_LitLength, LL_defaultNorm, MaxLL, LL_defaultNormLog, workspace, workspaceSize);
++ LLtype = set_basic;
++ } else {
++ size_t nbSeq_1 = nbSeq;
++ const U32 tableLog = FSE_optimalTableLog(LLFSELog, nbSeq, max);
++ if (count[llCodeTable[nbSeq - 1]] > 1) {
++ count[llCodeTable[nbSeq - 1]]--;
++ nbSeq_1--;
++ }
++ FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
++ {
++ size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */
++ if (FSE_isError(NCountSize))
++ return NCountSize;
++ op += NCountSize;
++ }
++ FSE_buildCTable_wksp(CTable_LitLength, norm, max, tableLog, workspace, workspaceSize);
++ LLtype = set_compressed;
++ }
++ }
++
++ /* CTable for Offsets */
++ {
++ U32 max = MaxOff;
++ size_t const mostFrequent = FSE_countFast_wksp(count, &max, ofCodeTable, nbSeq, workspace);
++ if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
++ *op++ = ofCodeTable[0];
++ FSE_buildCTable_rle(CTable_OffsetBits, (BYTE)max);
++ Offtype = set_rle;
++ } else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
++ Offtype = set_repeat;
++ } else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (OF_defaultNormLog - 1)))) {
++ FSE_buildCTable_wksp(CTable_OffsetBits, OF_defaultNorm, MaxOff, OF_defaultNormLog, workspace, workspaceSize);
++ Offtype = set_basic;
++ } else {
++ size_t nbSeq_1 = nbSeq;
++ const U32 tableLog = FSE_optimalTableLog(OffFSELog, nbSeq, max);
++ if (count[ofCodeTable[nbSeq - 1]] > 1) {
++ count[ofCodeTable[nbSeq - 1]]--;
++ nbSeq_1--;
++ }
++ FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
++ {
++ size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */
++ if (FSE_isError(NCountSize))
++ return NCountSize;
++ op += NCountSize;
++ }
++ FSE_buildCTable_wksp(CTable_OffsetBits, norm, max, tableLog, workspace, workspaceSize);
++ Offtype = set_compressed;
++ }
++ }
++
++ /* CTable for MatchLengths */
++ {
++ U32 max = MaxML;
++ size_t const mostFrequent = FSE_countFast_wksp(count, &max, mlCodeTable, nbSeq, workspace);
++ if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
++ *op++ = *mlCodeTable;
++ FSE_buildCTable_rle(CTable_MatchLength, (BYTE)max);
++ MLtype = set_rle;
++ } else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
++ MLtype = set_repeat;
++ } else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (ML_defaultNormLog - 1)))) {
++ FSE_buildCTable_wksp(CTable_MatchLength, ML_defaultNorm, MaxML, ML_defaultNormLog, workspace, workspaceSize);
++ MLtype = set_basic;
++ } else {
++ size_t nbSeq_1 = nbSeq;
++ const U32 tableLog = FSE_optimalTableLog(MLFSELog, nbSeq, max);
++ if (count[mlCodeTable[nbSeq - 1]] > 1) {
++ count[mlCodeTable[nbSeq - 1]]--;
++ nbSeq_1--;
++ }
++ FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
++ {
++ size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */
++ if (FSE_isError(NCountSize))
++ return NCountSize;
++ op += NCountSize;
++ }
++ FSE_buildCTable_wksp(CTable_MatchLength, norm, max, tableLog, workspace, workspaceSize);
++ MLtype = set_compressed;
++ }
++ }
++
++ *seqHead = (BYTE)((LLtype << 6) + (Offtype << 4) + (MLtype << 2));
++ zc->flagStaticTables = 0;
++
++ /* Encoding Sequences */
++ {
++ BIT_CStream_t blockStream;
++ FSE_CState_t stateMatchLength;
++ FSE_CState_t stateOffsetBits;
++ FSE_CState_t stateLitLength;
++
++ CHECK_E(BIT_initCStream(&blockStream, op, oend - op), dstSize_tooSmall); /* not enough space remaining */
++
++ /* first symbols */
++ FSE_initCState2(&stateMatchLength, CTable_MatchLength, mlCodeTable[nbSeq - 1]);
++ FSE_initCState2(&stateOffsetBits, CTable_OffsetBits, ofCodeTable[nbSeq - 1]);
++ FSE_initCState2(&stateLitLength, CTable_LitLength, llCodeTable[nbSeq - 1]);
++ BIT_addBits(&blockStream, sequences[nbSeq - 1].litLength, LL_bits[llCodeTable[nbSeq - 1]]);
++ if (ZSTD_32bits())
++ BIT_flushBits(&blockStream);
++ BIT_addBits(&blockStream, sequences[nbSeq - 1].matchLength, ML_bits[mlCodeTable[nbSeq - 1]]);
++ if (ZSTD_32bits())
++ BIT_flushBits(&blockStream);
++ if (longOffsets) {
++ U32 const ofBits = ofCodeTable[nbSeq - 1];
++ int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN - 1);
++ if (extraBits) {
++ BIT_addBits(&blockStream, sequences[nbSeq - 1].offset, extraBits);
++ BIT_flushBits(&blockStream);
++ }
++ BIT_addBits(&blockStream, sequences[nbSeq - 1].offset >> extraBits, ofBits - extraBits);
++ } else {
++ BIT_addBits(&blockStream, sequences[nbSeq - 1].offset, ofCodeTable[nbSeq - 1]);
++ }
++ BIT_flushBits(&blockStream);
++
++ {
++ size_t n;
++ for (n = nbSeq - 2; n < nbSeq; n--) { /* intentional underflow */
++ BYTE const llCode = llCodeTable[n];
++ BYTE const ofCode = ofCodeTable[n];
++ BYTE const mlCode = mlCodeTable[n];
++ U32 const llBits = LL_bits[llCode];
++ U32 const ofBits = ofCode; /* 32b*/ /* 64b*/
++ U32 const mlBits = ML_bits[mlCode];
++ /* (7)*/ /* (7)*/
++ FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode); /* 15 */ /* 15 */
++ FSE_encodeSymbol(&blockStream, &stateMatchLength, mlCode); /* 24 */ /* 24 */
++ if (ZSTD_32bits())
++ BIT_flushBits(&blockStream); /* (7)*/
++ FSE_encodeSymbol(&blockStream, &stateLitLength, llCode); /* 16 */ /* 33 */
++ if (ZSTD_32bits() || (ofBits + mlBits + llBits >= 64 - 7 - (LLFSELog + MLFSELog + OffFSELog)))
++ BIT_flushBits(&blockStream); /* (7)*/
++ BIT_addBits(&blockStream, sequences[n].litLength, llBits);
++ if (ZSTD_32bits() && ((llBits + mlBits) > 24))
++ BIT_flushBits(&blockStream);
++ BIT_addBits(&blockStream, sequences[n].matchLength, mlBits);
++ if (ZSTD_32bits())
++ BIT_flushBits(&blockStream); /* (7)*/
++ if (longOffsets) {
++ int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN - 1);
++ if (extraBits) {
++ BIT_addBits(&blockStream, sequences[n].offset, extraBits);
++ BIT_flushBits(&blockStream); /* (7)*/
++ }
++ BIT_addBits(&blockStream, sequences[n].offset >> extraBits, ofBits - extraBits); /* 31 */
++ } else {
++ BIT_addBits(&blockStream, sequences[n].offset, ofBits); /* 31 */
++ }
++ BIT_flushBits(&blockStream); /* (7)*/
++ }
++ }
++
++ FSE_flushCState(&blockStream, &stateMatchLength);
++ FSE_flushCState(&blockStream, &stateOffsetBits);
++ FSE_flushCState(&blockStream, &stateLitLength);
++
++ {
++ size_t const streamSize = BIT_closeCStream(&blockStream);
++ if (streamSize == 0)
++ return ERROR(dstSize_tooSmall); /* not enough space */
++ op += streamSize;
++ }
++ }
++ return op - ostart;
++}
++
++ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize)
++{
++ size_t const cSize = ZSTD_compressSequences_internal(zc, dst, dstCapacity);
++ size_t const minGain = ZSTD_minGain(srcSize);
++ size_t const maxCSize = srcSize - minGain;
++ /* If the srcSize <= dstCapacity, then there is enough space to write a
++ * raw uncompressed block. Since we ran out of space, the block must not
++ * be compressible, so fall back to a raw uncompressed block.
++ */
++ int const uncompressibleError = cSize == ERROR(dstSize_tooSmall) && srcSize <= dstCapacity;
++ int i;
++
++ if (ZSTD_isError(cSize) && !uncompressibleError)
++ return cSize;
++ if (cSize >= maxCSize || uncompressibleError) {
++ zc->flagStaticHufTable = HUF_repeat_none;
++ return 0;
++ }
++ /* confirm repcodes */
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ zc->rep[i] = zc->repToConfirm[i];
++ return cSize;
++}
++
++/*! ZSTD_storeSeq() :
++ Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
++ `offsetCode` : distance to match, or 0 == repCode.
++ `matchCode` : matchLength - MINMATCH
++*/
++ZSTD_STATIC void ZSTD_storeSeq(seqStore_t *seqStorePtr, size_t litLength, const void *literals, U32 offsetCode, size_t matchCode)
++{
++ /* copy Literals */
++ ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
++ seqStorePtr->lit += litLength;
++
++ /* literal Length */
++ if (litLength > 0xFFFF) {
++ seqStorePtr->longLengthID = 1;
++ seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
++ }
++ seqStorePtr->sequences[0].litLength = (U16)litLength;
++
++ /* match offset */
++ seqStorePtr->sequences[0].offset = offsetCode + 1;
++
++ /* match Length */
++ if (matchCode > 0xFFFF) {
++ seqStorePtr->longLengthID = 2;
++ seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
++ }
++ seqStorePtr->sequences[0].matchLength = (U16)matchCode;
++
++ seqStorePtr->sequences++;
++}
++
++/*-*************************************
++* Match length counter
++***************************************/
++static unsigned ZSTD_NbCommonBytes(register size_t val)
++{
++ if (ZSTD_isLittleEndian()) {
++ if (ZSTD_64bits()) {
++ return (__builtin_ctzll((U64)val) >> 3);
++ } else { /* 32 bits */
++ return (__builtin_ctz((U32)val) >> 3);
++ }
++ } else { /* Big Endian CPU */
++ if (ZSTD_64bits()) {
++ return (__builtin_clzll(val) >> 3);
++ } else { /* 32 bits */
++ return (__builtin_clz((U32)val) >> 3);
++ }
++ }
++}
++
++static size_t ZSTD_count(const BYTE *pIn, const BYTE *pMatch, const BYTE *const pInLimit)
++{
++ const BYTE *const pStart = pIn;
++ const BYTE *const pInLoopLimit = pInLimit - (sizeof(size_t) - 1);
++
++ while (pIn < pInLoopLimit) {
++ size_t const diff = ZSTD_readST(pMatch) ^ ZSTD_readST(pIn);
++ if (!diff) {
++ pIn += sizeof(size_t);
++ pMatch += sizeof(size_t);
++ continue;
++ }
++ pIn += ZSTD_NbCommonBytes(diff);
++ return (size_t)(pIn - pStart);
++ }
++ if (ZSTD_64bits())
++ if ((pIn < (pInLimit - 3)) && (ZSTD_read32(pMatch) == ZSTD_read32(pIn))) {
++ pIn += 4;
++ pMatch += 4;
++ }
++ if ((pIn < (pInLimit - 1)) && (ZSTD_read16(pMatch) == ZSTD_read16(pIn))) {
++ pIn += 2;
++ pMatch += 2;
++ }
++ if ((pIn < pInLimit) && (*pMatch == *pIn))
++ pIn++;
++ return (size_t)(pIn - pStart);
++}
++
++/** ZSTD_count_2segments() :
++* can count match length with `ip` & `match` in 2 different segments.
++* convention : on reaching mEnd, match count continue starting from iStart
++*/
++static size_t ZSTD_count_2segments(const BYTE *ip, const BYTE *match, const BYTE *iEnd, const BYTE *mEnd, const BYTE *iStart)
++{
++ const BYTE *const vEnd = MIN(ip + (mEnd - match), iEnd);
++ size_t const matchLength = ZSTD_count(ip, match, vEnd);
++ if (match + matchLength != mEnd)
++ return matchLength;
++ return matchLength + ZSTD_count(ip + matchLength, iStart, iEnd);
++}
++
++/*-*************************************
++* Hashes
++***************************************/
++static const U32 prime3bytes = 506832829U;
++static U32 ZSTD_hash3(U32 u, U32 h) { return ((u << (32 - 24)) * prime3bytes) >> (32 - h); }
++ZSTD_STATIC size_t ZSTD_hash3Ptr(const void *ptr, U32 h) { return ZSTD_hash3(ZSTD_readLE32(ptr), h); } /* only in zstd_opt.h */
++
++static const U32 prime4bytes = 2654435761U;
++static U32 ZSTD_hash4(U32 u, U32 h) { return (u * prime4bytes) >> (32 - h); }
++static size_t ZSTD_hash4Ptr(const void *ptr, U32 h) { return ZSTD_hash4(ZSTD_read32(ptr), h); }
++
++static const U64 prime5bytes = 889523592379ULL;
++static size_t ZSTD_hash5(U64 u, U32 h) { return (size_t)(((u << (64 - 40)) * prime5bytes) >> (64 - h)); }
++static size_t ZSTD_hash5Ptr(const void *p, U32 h) { return ZSTD_hash5(ZSTD_readLE64(p), h); }
++
++static const U64 prime6bytes = 227718039650203ULL;
++static size_t ZSTD_hash6(U64 u, U32 h) { return (size_t)(((u << (64 - 48)) * prime6bytes) >> (64 - h)); }
++static size_t ZSTD_hash6Ptr(const void *p, U32 h) { return ZSTD_hash6(ZSTD_readLE64(p), h); }
++
++static const U64 prime7bytes = 58295818150454627ULL;
++static size_t ZSTD_hash7(U64 u, U32 h) { return (size_t)(((u << (64 - 56)) * prime7bytes) >> (64 - h)); }
++static size_t ZSTD_hash7Ptr(const void *p, U32 h) { return ZSTD_hash7(ZSTD_readLE64(p), h); }
++
++static const U64 prime8bytes = 0xCF1BBCDCB7A56463ULL;
++static size_t ZSTD_hash8(U64 u, U32 h) { return (size_t)(((u)*prime8bytes) >> (64 - h)); }
++static size_t ZSTD_hash8Ptr(const void *p, U32 h) { return ZSTD_hash8(ZSTD_readLE64(p), h); }
++
++static size_t ZSTD_hashPtr(const void *p, U32 hBits, U32 mls)
++{
++ switch (mls) {
++ // case 3: return ZSTD_hash3Ptr(p, hBits);
++ default:
++ case 4: return ZSTD_hash4Ptr(p, hBits);
++ case 5: return ZSTD_hash5Ptr(p, hBits);
++ case 6: return ZSTD_hash6Ptr(p, hBits);
++ case 7: return ZSTD_hash7Ptr(p, hBits);
++ case 8: return ZSTD_hash8Ptr(p, hBits);
++ }
++}
++
++/*-*************************************
++* Fast Scan
++***************************************/
++static void ZSTD_fillHashTable(ZSTD_CCtx *zc, const void *end, const U32 mls)
++{
++ U32 *const hashTable = zc->hashTable;
++ U32 const hBits = zc->params.cParams.hashLog;
++ const BYTE *const base = zc->base;
++ const BYTE *ip = base + zc->nextToUpdate;
++ const BYTE *const iend = ((const BYTE *)end) - HASH_READ_SIZE;
++ const size_t fastHashFillStep = 3;
++
++ while (ip <= iend) {
++ hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base);
++ ip += fastHashFillStep;
++ }
++}
++
++FORCE_INLINE
++void ZSTD_compressBlock_fast_generic(ZSTD_CCtx *cctx, const void *src, size_t srcSize, const U32 mls)
++{
++ U32 *const hashTable = cctx->hashTable;
++ U32 const hBits = cctx->params.cParams.hashLog;
++ seqStore_t *seqStorePtr = &(cctx->seqStore);
++ const BYTE *const base = cctx->base;
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const U32 lowestIndex = cctx->dictLimit;
++ const BYTE *const lowest = base + lowestIndex;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - HASH_READ_SIZE;
++ U32 offset_1 = cctx->rep[0], offset_2 = cctx->rep[1];
++ U32 offsetSaved = 0;
++
++ /* init */
++ ip += (ip == lowest);
++ {
++ U32 const maxRep = (U32)(ip - lowest);
++ if (offset_2 > maxRep)
++ offsetSaved = offset_2, offset_2 = 0;
++ if (offset_1 > maxRep)
++ offsetSaved = offset_1, offset_1 = 0;
++ }
++
++ /* Main Search Loop */
++ while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
++ size_t mLength;
++ size_t const h = ZSTD_hashPtr(ip, hBits, mls);
++ U32 const curr = (U32)(ip - base);
++ U32 const matchIndex = hashTable[h];
++ const BYTE *match = base + matchIndex;
++ hashTable[h] = curr; /* update hash table */
++
++ if ((offset_1 > 0) & (ZSTD_read32(ip + 1 - offset_1) == ZSTD_read32(ip + 1))) {
++ mLength = ZSTD_count(ip + 1 + 4, ip + 1 + 4 - offset_1, iend) + 4;
++ ip++;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH);
++ } else {
++ U32 offset;
++ if ((matchIndex <= lowestIndex) || (ZSTD_read32(match) != ZSTD_read32(ip))) {
++ ip += ((ip - anchor) >> g_searchStrength) + 1;
++ continue;
++ }
++ mLength = ZSTD_count(ip + 4, match + 4, iend) + 4;
++ offset = (U32)(ip - match);
++ while (((ip > anchor) & (match > lowest)) && (ip[-1] == match[-1])) {
++ ip--;
++ match--;
++ mLength++;
++ } /* catch up */
++ offset_2 = offset_1;
++ offset_1 = offset;
++
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
++ }
++
++ /* match found */
++ ip += mLength;
++ anchor = ip;
++
++ if (ip <= ilimit) {
++ /* Fill Table */
++ hashTable[ZSTD_hashPtr(base + curr + 2, hBits, mls)] = curr + 2; /* here because curr+2 could be > iend-8 */
++ hashTable[ZSTD_hashPtr(ip - 2, hBits, mls)] = (U32)(ip - 2 - base);
++ /* check immediate repcode */
++ while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) {
++ /* store sequence */
++ size_t const rLength = ZSTD_count(ip + 4, ip + 4 - offset_2, iend) + 4;
++ {
++ U32 const tmpOff = offset_2;
++ offset_2 = offset_1;
++ offset_1 = tmpOff;
++ } /* swap offset_2 <=> offset_1 */
++ hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base);
++ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength - MINMATCH);
++ ip += rLength;
++ anchor = ip;
++ continue; /* faster when present ... (?) */
++ }
++ }
++ }
++
++ /* save reps for next block */
++ cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved;
++ cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved;
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++static void ZSTD_compressBlock_fast(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ const U32 mls = ctx->params.cParams.searchLength;
++ switch (mls) {
++ default: /* includes case 3 */
++ case 4: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 4); return;
++ case 5: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 5); return;
++ case 6: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 6); return;
++ case 7: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 7); return;
++ }
++}
++
++static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 mls)
++{
++ U32 *hashTable = ctx->hashTable;
++ const U32 hBits = ctx->params.cParams.hashLog;
++ seqStore_t *seqStorePtr = &(ctx->seqStore);
++ const BYTE *const base = ctx->base;
++ const BYTE *const dictBase = ctx->dictBase;
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const U32 lowestIndex = ctx->lowLimit;
++ const BYTE *const dictStart = dictBase + lowestIndex;
++ const U32 dictLimit = ctx->dictLimit;
++ const BYTE *const lowPrefixPtr = base + dictLimit;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - 8;
++ U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1];
++
++ /* Search Loop */
++ while (ip < ilimit) { /* < instead of <=, because (ip+1) */
++ const size_t h = ZSTD_hashPtr(ip, hBits, mls);
++ const U32 matchIndex = hashTable[h];
++ const BYTE *matchBase = matchIndex < dictLimit ? dictBase : base;
++ const BYTE *match = matchBase + matchIndex;
++ const U32 curr = (U32)(ip - base);
++ const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */
++ const BYTE *repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *repMatch = repBase + repIndex;
++ size_t mLength;
++ hashTable[h] = curr; /* update hash table */
++
++ if ((((U32)((dictLimit - 1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex)) &&
++ (ZSTD_read32(repMatch) == ZSTD_read32(ip + 1))) {
++ const BYTE *repMatchEnd = repIndex < dictLimit ? dictEnd : iend;
++ mLength = ZSTD_count_2segments(ip + 1 + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repMatchEnd, lowPrefixPtr) + EQUAL_READ32;
++ ip++;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH);
++ } else {
++ if ((matchIndex < lowestIndex) || (ZSTD_read32(match) != ZSTD_read32(ip))) {
++ ip += ((ip - anchor) >> g_searchStrength) + 1;
++ continue;
++ }
++ {
++ const BYTE *matchEnd = matchIndex < dictLimit ? dictEnd : iend;
++ const BYTE *lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr;
++ U32 offset;
++ mLength = ZSTD_count_2segments(ip + EQUAL_READ32, match + EQUAL_READ32, iend, matchEnd, lowPrefixPtr) + EQUAL_READ32;
++ while (((ip > anchor) & (match > lowMatchPtr)) && (ip[-1] == match[-1])) {
++ ip--;
++ match--;
++ mLength++;
++ } /* catch up */
++ offset = curr - matchIndex;
++ offset_2 = offset_1;
++ offset_1 = offset;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
++ }
++ }
++
++ /* found a match : store it */
++ ip += mLength;
++ anchor = ip;
++
++ if (ip <= ilimit) {
++ /* Fill Table */
++ hashTable[ZSTD_hashPtr(base + curr + 2, hBits, mls)] = curr + 2;
++ hashTable[ZSTD_hashPtr(ip - 2, hBits, mls)] = (U32)(ip - 2 - base);
++ /* check immediate repcode */
++ while (ip <= ilimit) {
++ U32 const curr2 = (U32)(ip - base);
++ U32 const repIndex2 = curr2 - offset_2;
++ const BYTE *repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2;
++ if ((((U32)((dictLimit - 1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */
++ && (ZSTD_read32(repMatch2) == ZSTD_read32(ip))) {
++ const BYTE *const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend;
++ size_t repLength2 =
++ ZSTD_count_2segments(ip + EQUAL_READ32, repMatch2 + EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32;
++ U32 tmpOffset = offset_2;
++ offset_2 = offset_1;
++ offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
++ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, repLength2 - MINMATCH);
++ hashTable[ZSTD_hashPtr(ip, hBits, mls)] = curr2;
++ ip += repLength2;
++ anchor = ip;
++ continue;
++ }
++ break;
++ }
++ }
++ }
++
++ /* save reps for next block */
++ ctx->repToConfirm[0] = offset_1;
++ ctx->repToConfirm[1] = offset_2;
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ U32 const mls = ctx->params.cParams.searchLength;
++ switch (mls) {
++ default: /* includes case 3 */
++ case 4: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 4); return;
++ case 5: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 5); return;
++ case 6: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 6); return;
++ case 7: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 7); return;
++ }
++}
++
++/*-*************************************
++* Double Fast
++***************************************/
++static void ZSTD_fillDoubleHashTable(ZSTD_CCtx *cctx, const void *end, const U32 mls)
++{
++ U32 *const hashLarge = cctx->hashTable;
++ U32 const hBitsL = cctx->params.cParams.hashLog;
++ U32 *const hashSmall = cctx->chainTable;
++ U32 const hBitsS = cctx->params.cParams.chainLog;
++ const BYTE *const base = cctx->base;
++ const BYTE *ip = base + cctx->nextToUpdate;
++ const BYTE *const iend = ((const BYTE *)end) - HASH_READ_SIZE;
++ const size_t fastHashFillStep = 3;
++
++ while (ip <= iend) {
++ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base);
++ hashLarge[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base);
++ ip += fastHashFillStep;
++ }
++}
++
++FORCE_INLINE
++void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx *cctx, const void *src, size_t srcSize, const U32 mls)
++{
++ U32 *const hashLong = cctx->hashTable;
++ const U32 hBitsL = cctx->params.cParams.hashLog;
++ U32 *const hashSmall = cctx->chainTable;
++ const U32 hBitsS = cctx->params.cParams.chainLog;
++ seqStore_t *seqStorePtr = &(cctx->seqStore);
++ const BYTE *const base = cctx->base;
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const U32 lowestIndex = cctx->dictLimit;
++ const BYTE *const lowest = base + lowestIndex;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - HASH_READ_SIZE;
++ U32 offset_1 = cctx->rep[0], offset_2 = cctx->rep[1];
++ U32 offsetSaved = 0;
++
++ /* init */
++ ip += (ip == lowest);
++ {
++ U32 const maxRep = (U32)(ip - lowest);
++ if (offset_2 > maxRep)
++ offsetSaved = offset_2, offset_2 = 0;
++ if (offset_1 > maxRep)
++ offsetSaved = offset_1, offset_1 = 0;
++ }
++
++ /* Main Search Loop */
++ while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
++ size_t mLength;
++ size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8);
++ size_t const h = ZSTD_hashPtr(ip, hBitsS, mls);
++ U32 const curr = (U32)(ip - base);
++ U32 const matchIndexL = hashLong[h2];
++ U32 const matchIndexS = hashSmall[h];
++ const BYTE *matchLong = base + matchIndexL;
++ const BYTE *match = base + matchIndexS;
++ hashLong[h2] = hashSmall[h] = curr; /* update hash tables */
++
++ if ((offset_1 > 0) & (ZSTD_read32(ip + 1 - offset_1) == ZSTD_read32(ip + 1))) { /* note : by construction, offset_1 <= curr */
++ mLength = ZSTD_count(ip + 1 + 4, ip + 1 + 4 - offset_1, iend) + 4;
++ ip++;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH);
++ } else {
++ U32 offset;
++ if ((matchIndexL > lowestIndex) && (ZSTD_read64(matchLong) == ZSTD_read64(ip))) {
++ mLength = ZSTD_count(ip + 8, matchLong + 8, iend) + 8;
++ offset = (U32)(ip - matchLong);
++ while (((ip > anchor) & (matchLong > lowest)) && (ip[-1] == matchLong[-1])) {
++ ip--;
++ matchLong--;
++ mLength++;
++ } /* catch up */
++ } else if ((matchIndexS > lowestIndex) && (ZSTD_read32(match) == ZSTD_read32(ip))) {
++ size_t const h3 = ZSTD_hashPtr(ip + 1, hBitsL, 8);
++ U32 const matchIndex3 = hashLong[h3];
++ const BYTE *match3 = base + matchIndex3;
++ hashLong[h3] = curr + 1;
++ if ((matchIndex3 > lowestIndex) && (ZSTD_read64(match3) == ZSTD_read64(ip + 1))) {
++ mLength = ZSTD_count(ip + 9, match3 + 8, iend) + 8;
++ ip++;
++ offset = (U32)(ip - match3);
++ while (((ip > anchor) & (match3 > lowest)) && (ip[-1] == match3[-1])) {
++ ip--;
++ match3--;
++ mLength++;
++ } /* catch up */
++ } else {
++ mLength = ZSTD_count(ip + 4, match + 4, iend) + 4;
++ offset = (U32)(ip - match);
++ while (((ip > anchor) & (match > lowest)) && (ip[-1] == match[-1])) {
++ ip--;
++ match--;
++ mLength++;
++ } /* catch up */
++ }
++ } else {
++ ip += ((ip - anchor) >> g_searchStrength) + 1;
++ continue;
++ }
++
++ offset_2 = offset_1;
++ offset_1 = offset;
++
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
++ }
++
++ /* match found */
++ ip += mLength;
++ anchor = ip;
++
++ if (ip <= ilimit) {
++ /* Fill Table */
++ hashLong[ZSTD_hashPtr(base + curr + 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(base + curr + 2, hBitsS, mls)] =
++ curr + 2; /* here because curr+2 could be > iend-8 */
++ hashLong[ZSTD_hashPtr(ip - 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(ip - 2, hBitsS, mls)] = (U32)(ip - 2 - base);
++
++ /* check immediate repcode */
++ while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) {
++ /* store sequence */
++ size_t const rLength = ZSTD_count(ip + 4, ip + 4 - offset_2, iend) + 4;
++ {
++ U32 const tmpOff = offset_2;
++ offset_2 = offset_1;
++ offset_1 = tmpOff;
++ } /* swap offset_2 <=> offset_1 */
++ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base);
++ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base);
++ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength - MINMATCH);
++ ip += rLength;
++ anchor = ip;
++ continue; /* faster when present ... (?) */
++ }
++ }
++ }
++
++ /* save reps for next block */
++ cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved;
++ cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved;
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++static void ZSTD_compressBlock_doubleFast(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ const U32 mls = ctx->params.cParams.searchLength;
++ switch (mls) {
++ default: /* includes case 3 */
++ case 4: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 4); return;
++ case 5: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 5); return;
++ case 6: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 6); return;
++ case 7: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 7); return;
++ }
++}
++
++static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 mls)
++{
++ U32 *const hashLong = ctx->hashTable;
++ U32 const hBitsL = ctx->params.cParams.hashLog;
++ U32 *const hashSmall = ctx->chainTable;
++ U32 const hBitsS = ctx->params.cParams.chainLog;
++ seqStore_t *seqStorePtr = &(ctx->seqStore);
++ const BYTE *const base = ctx->base;
++ const BYTE *const dictBase = ctx->dictBase;
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const U32 lowestIndex = ctx->lowLimit;
++ const BYTE *const dictStart = dictBase + lowestIndex;
++ const U32 dictLimit = ctx->dictLimit;
++ const BYTE *const lowPrefixPtr = base + dictLimit;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - 8;
++ U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1];
++
++ /* Search Loop */
++ while (ip < ilimit) { /* < instead of <=, because (ip+1) */
++ const size_t hSmall = ZSTD_hashPtr(ip, hBitsS, mls);
++ const U32 matchIndex = hashSmall[hSmall];
++ const BYTE *matchBase = matchIndex < dictLimit ? dictBase : base;
++ const BYTE *match = matchBase + matchIndex;
++
++ const size_t hLong = ZSTD_hashPtr(ip, hBitsL, 8);
++ const U32 matchLongIndex = hashLong[hLong];
++ const BYTE *matchLongBase = matchLongIndex < dictLimit ? dictBase : base;
++ const BYTE *matchLong = matchLongBase + matchLongIndex;
++
++ const U32 curr = (U32)(ip - base);
++ const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */
++ const BYTE *repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *repMatch = repBase + repIndex;
++ size_t mLength;
++ hashSmall[hSmall] = hashLong[hLong] = curr; /* update hash table */
++
++ if ((((U32)((dictLimit - 1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex)) &&
++ (ZSTD_read32(repMatch) == ZSTD_read32(ip + 1))) {
++ const BYTE *repMatchEnd = repIndex < dictLimit ? dictEnd : iend;
++ mLength = ZSTD_count_2segments(ip + 1 + 4, repMatch + 4, iend, repMatchEnd, lowPrefixPtr) + 4;
++ ip++;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH);
++ } else {
++ if ((matchLongIndex > lowestIndex) && (ZSTD_read64(matchLong) == ZSTD_read64(ip))) {
++ const BYTE *matchEnd = matchLongIndex < dictLimit ? dictEnd : iend;
++ const BYTE *lowMatchPtr = matchLongIndex < dictLimit ? dictStart : lowPrefixPtr;
++ U32 offset;
++ mLength = ZSTD_count_2segments(ip + 8, matchLong + 8, iend, matchEnd, lowPrefixPtr) + 8;
++ offset = curr - matchLongIndex;
++ while (((ip > anchor) & (matchLong > lowMatchPtr)) && (ip[-1] == matchLong[-1])) {
++ ip--;
++ matchLong--;
++ mLength++;
++ } /* catch up */
++ offset_2 = offset_1;
++ offset_1 = offset;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
++
++ } else if ((matchIndex > lowestIndex) && (ZSTD_read32(match) == ZSTD_read32(ip))) {
++ size_t const h3 = ZSTD_hashPtr(ip + 1, hBitsL, 8);
++ U32 const matchIndex3 = hashLong[h3];
++ const BYTE *const match3Base = matchIndex3 < dictLimit ? dictBase : base;
++ const BYTE *match3 = match3Base + matchIndex3;
++ U32 offset;
++ hashLong[h3] = curr + 1;
++ if ((matchIndex3 > lowestIndex) && (ZSTD_read64(match3) == ZSTD_read64(ip + 1))) {
++ const BYTE *matchEnd = matchIndex3 < dictLimit ? dictEnd : iend;
++ const BYTE *lowMatchPtr = matchIndex3 < dictLimit ? dictStart : lowPrefixPtr;
++ mLength = ZSTD_count_2segments(ip + 9, match3 + 8, iend, matchEnd, lowPrefixPtr) + 8;
++ ip++;
++ offset = curr + 1 - matchIndex3;
++ while (((ip > anchor) & (match3 > lowMatchPtr)) && (ip[-1] == match3[-1])) {
++ ip--;
++ match3--;
++ mLength++;
++ } /* catch up */
++ } else {
++ const BYTE *matchEnd = matchIndex < dictLimit ? dictEnd : iend;
++ const BYTE *lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr;
++ mLength = ZSTD_count_2segments(ip + 4, match + 4, iend, matchEnd, lowPrefixPtr) + 4;
++ offset = curr - matchIndex;
++ while (((ip > anchor) & (match > lowMatchPtr)) && (ip[-1] == match[-1])) {
++ ip--;
++ match--;
++ mLength++;
++ } /* catch up */
++ }
++ offset_2 = offset_1;
++ offset_1 = offset;
++ ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH);
++
++ } else {
++ ip += ((ip - anchor) >> g_searchStrength) + 1;
++ continue;
++ }
++ }
++
++ /* found a match : store it */
++ ip += mLength;
++ anchor = ip;
++
++ if (ip <= ilimit) {
++ /* Fill Table */
++ hashSmall[ZSTD_hashPtr(base + curr + 2, hBitsS, mls)] = curr + 2;
++ hashLong[ZSTD_hashPtr(base + curr + 2, hBitsL, 8)] = curr + 2;
++ hashSmall[ZSTD_hashPtr(ip - 2, hBitsS, mls)] = (U32)(ip - 2 - base);
++ hashLong[ZSTD_hashPtr(ip - 2, hBitsL, 8)] = (U32)(ip - 2 - base);
++ /* check immediate repcode */
++ while (ip <= ilimit) {
++ U32 const curr2 = (U32)(ip - base);
++ U32 const repIndex2 = curr2 - offset_2;
++ const BYTE *repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2;
++ if ((((U32)((dictLimit - 1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */
++ && (ZSTD_read32(repMatch2) == ZSTD_read32(ip))) {
++ const BYTE *const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend;
++ size_t const repLength2 =
++ ZSTD_count_2segments(ip + EQUAL_READ32, repMatch2 + EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32;
++ U32 tmpOffset = offset_2;
++ offset_2 = offset_1;
++ offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
++ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, repLength2 - MINMATCH);
++ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = curr2;
++ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = curr2;
++ ip += repLength2;
++ anchor = ip;
++ continue;
++ }
++ break;
++ }
++ }
++ }
++
++ /* save reps for next block */
++ ctx->repToConfirm[0] = offset_1;
++ ctx->repToConfirm[1] = offset_2;
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++static void ZSTD_compressBlock_doubleFast_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ U32 const mls = ctx->params.cParams.searchLength;
++ switch (mls) {
++ default: /* includes case 3 */
++ case 4: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 4); return;
++ case 5: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 5); return;
++ case 6: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 6); return;
++ case 7: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 7); return;
++ }
++}
++
++/*-*************************************
++* Binary Tree search
++***************************************/
++/** ZSTD_insertBt1() : add one or multiple positions to tree.
++* ip : assumed <= iend-8 .
++* @return : nb of positions added */
++static U32 ZSTD_insertBt1(ZSTD_CCtx *zc, const BYTE *const ip, const U32 mls, const BYTE *const iend, U32 nbCompares, U32 extDict)
++{
++ U32 *const hashTable = zc->hashTable;
++ U32 const hashLog = zc->params.cParams.hashLog;
++ size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
++ U32 *const bt = zc->chainTable;
++ U32 const btLog = zc->params.cParams.chainLog - 1;
++ U32 const btMask = (1 << btLog) - 1;
++ U32 matchIndex = hashTable[h];
++ size_t commonLengthSmaller = 0, commonLengthLarger = 0;
++ const BYTE *const base = zc->base;
++ const BYTE *const dictBase = zc->dictBase;
++ const U32 dictLimit = zc->dictLimit;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const BYTE *const prefixStart = base + dictLimit;
++ const BYTE *match;
++ const U32 curr = (U32)(ip - base);
++ const U32 btLow = btMask >= curr ? 0 : curr - btMask;
++ U32 *smallerPtr = bt + 2 * (curr & btMask);
++ U32 *largerPtr = smallerPtr + 1;
++ U32 dummy32; /* to be nullified at the end */
++ U32 const windowLow = zc->lowLimit;
++ U32 matchEndIdx = curr + 8;
++ size_t bestLength = 8;
++
++ hashTable[h] = curr; /* Update Hash Table */
++
++ while (nbCompares-- && (matchIndex > windowLow)) {
++ U32 *const nextPtr = bt + 2 * (matchIndex & btMask);
++ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
++
++ if ((!extDict) || (matchIndex + matchLength >= dictLimit)) {
++ match = base + matchIndex;
++ if (match[matchLength] == ip[matchLength])
++ matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iend) + 1;
++ } else {
++ match = dictBase + matchIndex;
++ matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iend, dictEnd, prefixStart);
++ if (matchIndex + matchLength >= dictLimit)
++ match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
++ }
++
++ if (matchLength > bestLength) {
++ bestLength = matchLength;
++ if (matchLength > matchEndIdx - matchIndex)
++ matchEndIdx = matchIndex + (U32)matchLength;
++ }
++
++ if (ip + matchLength == iend) /* equal : no way to know if inf or sup */
++ break; /* drop , to guarantee consistency ; miss a bit of compression, but other solutions can corrupt the tree */
++
++ if (match[matchLength] < ip[matchLength]) { /* necessarily within correct buffer */
++ /* match is smaller than curr */
++ *smallerPtr = matchIndex; /* update smaller idx */
++ commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
++ if (matchIndex <= btLow) {
++ smallerPtr = &dummy32;
++ break;
++ } /* beyond tree size, stop the search */
++ smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */
++ matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */
++ } else {
++ /* match is larger than curr */
++ *largerPtr = matchIndex;
++ commonLengthLarger = matchLength;
++ if (matchIndex <= btLow) {
++ largerPtr = &dummy32;
++ break;
++ } /* beyond tree size, stop the search */
++ largerPtr = nextPtr;
++ matchIndex = nextPtr[0];
++ }
++ }
++
++ *smallerPtr = *largerPtr = 0;
++ if (bestLength > 384)
++ return MIN(192, (U32)(bestLength - 384)); /* speed optimization */
++ if (matchEndIdx > curr + 8)
++ return matchEndIdx - curr - 8;
++ return 1;
++}
++
++static size_t ZSTD_insertBtAndFindBestMatch(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, size_t *offsetPtr, U32 nbCompares, const U32 mls,
++ U32 extDict)
++{
++ U32 *const hashTable = zc->hashTable;
++ U32 const hashLog = zc->params.cParams.hashLog;
++ size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
++ U32 *const bt = zc->chainTable;
++ U32 const btLog = zc->params.cParams.chainLog - 1;
++ U32 const btMask = (1 << btLog) - 1;
++ U32 matchIndex = hashTable[h];
++ size_t commonLengthSmaller = 0, commonLengthLarger = 0;
++ const BYTE *const base = zc->base;
++ const BYTE *const dictBase = zc->dictBase;
++ const U32 dictLimit = zc->dictLimit;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const BYTE *const prefixStart = base + dictLimit;
++ const U32 curr = (U32)(ip - base);
++ const U32 btLow = btMask >= curr ? 0 : curr - btMask;
++ const U32 windowLow = zc->lowLimit;
++ U32 *smallerPtr = bt + 2 * (curr & btMask);
++ U32 *largerPtr = bt + 2 * (curr & btMask) + 1;
++ U32 matchEndIdx = curr + 8;
++ U32 dummy32; /* to be nullified at the end */
++ size_t bestLength = 0;
++
++ hashTable[h] = curr; /* Update Hash Table */
++
++ while (nbCompares-- && (matchIndex > windowLow)) {
++ U32 *const nextPtr = bt + 2 * (matchIndex & btMask);
++ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
++ const BYTE *match;
++
++ if ((!extDict) || (matchIndex + matchLength >= dictLimit)) {
++ match = base + matchIndex;
++ if (match[matchLength] == ip[matchLength])
++ matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iend) + 1;
++ } else {
++ match = dictBase + matchIndex;
++ matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iend, dictEnd, prefixStart);
++ if (matchIndex + matchLength >= dictLimit)
++ match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
++ }
++
++ if (matchLength > bestLength) {
++ if (matchLength > matchEndIdx - matchIndex)
++ matchEndIdx = matchIndex + (U32)matchLength;
++ if ((4 * (int)(matchLength - bestLength)) > (int)(ZSTD_highbit32(curr - matchIndex + 1) - ZSTD_highbit32((U32)offsetPtr[0] + 1)))
++ bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + curr - matchIndex;
++ if (ip + matchLength == iend) /* equal : no way to know if inf or sup */
++ break; /* drop, to guarantee consistency (miss a little bit of compression) */
++ }
++
++ if (match[matchLength] < ip[matchLength]) {
++ /* match is smaller than curr */
++ *smallerPtr = matchIndex; /* update smaller idx */
++ commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
++ if (matchIndex <= btLow) {
++ smallerPtr = &dummy32;
++ break;
++ } /* beyond tree size, stop the search */
++ smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */
++ matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */
++ } else {
++ /* match is larger than curr */
++ *largerPtr = matchIndex;
++ commonLengthLarger = matchLength;
++ if (matchIndex <= btLow) {
++ largerPtr = &dummy32;
++ break;
++ } /* beyond tree size, stop the search */
++ largerPtr = nextPtr;
++ matchIndex = nextPtr[0];
++ }
++ }
++
++ *smallerPtr = *largerPtr = 0;
++
++ zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1;
++ return bestLength;
++}
++
++static void ZSTD_updateTree(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, const U32 nbCompares, const U32 mls)
++{
++ const BYTE *const base = zc->base;
++ const U32 target = (U32)(ip - base);
++ U32 idx = zc->nextToUpdate;
++
++ while (idx < target)
++ idx += ZSTD_insertBt1(zc, base + idx, mls, iend, nbCompares, 0);
++}
++
++/** ZSTD_BtFindBestMatch() : Tree updater, providing best match */
++static size_t ZSTD_BtFindBestMatch(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 mls)
++{
++ if (ip < zc->base + zc->nextToUpdate)
++ return 0; /* skipped area */
++ ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
++ return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 0);
++}
++
++static size_t ZSTD_BtFindBestMatch_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */
++ const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 matchLengthSearch)
++{
++ switch (matchLengthSearch) {
++ default: /* includes case 3 */
++ case 4: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
++ case 5: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
++ case 7:
++ case 6: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6);
++ }
++}
++
++static void ZSTD_updateTree_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, const U32 nbCompares, const U32 mls)
++{
++ const BYTE *const base = zc->base;
++ const U32 target = (U32)(ip - base);
++ U32 idx = zc->nextToUpdate;
++
++ while (idx < target)
++ idx += ZSTD_insertBt1(zc, base + idx, mls, iend, nbCompares, 1);
++}
++
++/** Tree updater, providing best match */
++static size_t ZSTD_BtFindBestMatch_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts,
++ const U32 mls)
++{
++ if (ip < zc->base + zc->nextToUpdate)
++ return 0; /* skipped area */
++ ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
++ return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 1);
++}
++
++static size_t ZSTD_BtFindBestMatch_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */
++ const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts,
++ const U32 matchLengthSearch)
++{
++ switch (matchLengthSearch) {
++ default: /* includes case 3 */
++ case 4: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
++ case 5: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
++ case 7:
++ case 6: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6);
++ }
++}
++
++/* *********************************
++* Hash Chain
++***********************************/
++#define NEXT_IN_CHAIN(d, mask) chainTable[(d)&mask]
++
++/* Update chains up to ip (excluded)
++ Assumption : always within prefix (i.e. not within extDict) */
++FORCE_INLINE
++U32 ZSTD_insertAndFindFirstIndex(ZSTD_CCtx *zc, const BYTE *ip, U32 mls)
++{
++ U32 *const hashTable = zc->hashTable;
++ const U32 hashLog = zc->params.cParams.hashLog;
++ U32 *const chainTable = zc->chainTable;
++ const U32 chainMask = (1 << zc->params.cParams.chainLog) - 1;
++ const BYTE *const base = zc->base;
++ const U32 target = (U32)(ip - base);
++ U32 idx = zc->nextToUpdate;
++
++ while (idx < target) { /* catch up */
++ size_t const h = ZSTD_hashPtr(base + idx, hashLog, mls);
++ NEXT_IN_CHAIN(idx, chainMask) = hashTable[h];
++ hashTable[h] = idx;
++ idx++;
++ }
++
++ zc->nextToUpdate = target;
++ return hashTable[ZSTD_hashPtr(ip, hashLog, mls)];
++}
++
++/* inlining is important to hardwire a hot branch (template emulation) */
++FORCE_INLINE
++size_t ZSTD_HcFindBestMatch_generic(ZSTD_CCtx *zc, /* Index table will be updated */
++ const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 mls,
++ const U32 extDict)
++{
++ U32 *const chainTable = zc->chainTable;
++ const U32 chainSize = (1 << zc->params.cParams.chainLog);
++ const U32 chainMask = chainSize - 1;
++ const BYTE *const base = zc->base;
++ const BYTE *const dictBase = zc->dictBase;
++ const U32 dictLimit = zc->dictLimit;
++ const BYTE *const prefixStart = base + dictLimit;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const U32 lowLimit = zc->lowLimit;
++ const U32 curr = (U32)(ip - base);
++ const U32 minChain = curr > chainSize ? curr - chainSize : 0;
++ int nbAttempts = maxNbAttempts;
++ size_t ml = EQUAL_READ32 - 1;
++
++ /* HC4 match finder */
++ U32 matchIndex = ZSTD_insertAndFindFirstIndex(zc, ip, mls);
++
++ for (; (matchIndex > lowLimit) & (nbAttempts > 0); nbAttempts--) {
++ const BYTE *match;
++ size_t currMl = 0;
++ if ((!extDict) || matchIndex >= dictLimit) {
++ match = base + matchIndex;
++ if (match[ml] == ip[ml]) /* potentially better */
++ currMl = ZSTD_count(ip, match, iLimit);
++ } else {
++ match = dictBase + matchIndex;
++ if (ZSTD_read32(match) == ZSTD_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */
++ currMl = ZSTD_count_2segments(ip + EQUAL_READ32, match + EQUAL_READ32, iLimit, dictEnd, prefixStart) + EQUAL_READ32;
++ }
++
++ /* save best solution */
++ if (currMl > ml) {
++ ml = currMl;
++ *offsetPtr = curr - matchIndex + ZSTD_REP_MOVE;
++ if (ip + currMl == iLimit)
++ break; /* best possible, and avoid read overflow*/
++ }
++
++ if (matchIndex <= minChain)
++ break;
++ matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask);
++ }
++
++ return ml;
++}
++
++FORCE_INLINE size_t ZSTD_HcFindBestMatch_selectMLS(ZSTD_CCtx *zc, const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts,
++ const U32 matchLengthSearch)
++{
++ switch (matchLengthSearch) {
++ default: /* includes case 3 */
++ case 4: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 0);
++ case 5: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 0);
++ case 7:
++ case 6: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 0);
++ }
++}
++
++FORCE_INLINE size_t ZSTD_HcFindBestMatch_extDict_selectMLS(ZSTD_CCtx *zc, const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts,
++ const U32 matchLengthSearch)
++{
++ switch (matchLengthSearch) {
++ default: /* includes case 3 */
++ case 4: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 1);
++ case 5: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 1);
++ case 7:
++ case 6: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 1);
++ }
++}
++
++/* *******************************
++* Common parser - lazy strategy
++*********************************/
++FORCE_INLINE
++void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 searchMethod, const U32 depth)
++{
++ seqStore_t *seqStorePtr = &(ctx->seqStore);
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - 8;
++ const BYTE *const base = ctx->base + ctx->dictLimit;
++
++ U32 const maxSearches = 1 << ctx->params.cParams.searchLog;
++ U32 const mls = ctx->params.cParams.searchLength;
++
++ typedef size_t (*searchMax_f)(ZSTD_CCtx * zc, const BYTE *ip, const BYTE *iLimit, size_t *offsetPtr, U32 maxNbAttempts, U32 matchLengthSearch);
++ searchMax_f const searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS;
++ U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1], savedOffset = 0;
++
++ /* init */
++ ip += (ip == base);
++ ctx->nextToUpdate3 = ctx->nextToUpdate;
++ {
++ U32 const maxRep = (U32)(ip - base);
++ if (offset_2 > maxRep)
++ savedOffset = offset_2, offset_2 = 0;
++ if (offset_1 > maxRep)
++ savedOffset = offset_1, offset_1 = 0;
++ }
++
++ /* Match Loop */
++ while (ip < ilimit) {
++ size_t matchLength = 0;
++ size_t offset = 0;
++ const BYTE *start = ip + 1;
++
++ /* check repCode */
++ if ((offset_1 > 0) & (ZSTD_read32(ip + 1) == ZSTD_read32(ip + 1 - offset_1))) {
++ /* repcode : we take it */
++ matchLength = ZSTD_count(ip + 1 + EQUAL_READ32, ip + 1 + EQUAL_READ32 - offset_1, iend) + EQUAL_READ32;
++ if (depth == 0)
++ goto _storeSequence;
++ }
++
++ /* first search (depth 0) */
++ {
++ size_t offsetFound = 99999999;
++ size_t const ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls);
++ if (ml2 > matchLength)
++ matchLength = ml2, start = ip, offset = offsetFound;
++ }
++
++ if (matchLength < EQUAL_READ32) {
++ ip += ((ip - anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
++ continue;
++ }
++
++ /* let's try to find a better solution */
++ if (depth >= 1)
++ while (ip < ilimit) {
++ ip++;
++ if ((offset) && ((offset_1 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_1)))) {
++ size_t const mlRep = ZSTD_count(ip + EQUAL_READ32, ip + EQUAL_READ32 - offset_1, iend) + EQUAL_READ32;
++ int const gain2 = (int)(mlRep * 3);
++ int const gain1 = (int)(matchLength * 3 - ZSTD_highbit32((U32)offset + 1) + 1);
++ if ((mlRep >= EQUAL_READ32) && (gain2 > gain1))
++ matchLength = mlRep, offset = 0, start = ip;
++ }
++ {
++ size_t offset2 = 99999999;
++ size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
++ int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */
++ int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 4);
++ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
++ matchLength = ml2, offset = offset2, start = ip;
++ continue; /* search a better one */
++ }
++ }
++
++ /* let's find an even better one */
++ if ((depth == 2) && (ip < ilimit)) {
++ ip++;
++ if ((offset) && ((offset_1 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_1)))) {
++ size_t const ml2 = ZSTD_count(ip + EQUAL_READ32, ip + EQUAL_READ32 - offset_1, iend) + EQUAL_READ32;
++ int const gain2 = (int)(ml2 * 4);
++ int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 1);
++ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1))
++ matchLength = ml2, offset = 0, start = ip;
++ }
++ {
++ size_t offset2 = 99999999;
++ size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
++ int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */
++ int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 7);
++ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
++ matchLength = ml2, offset = offset2, start = ip;
++ continue;
++ }
++ }
++ }
++ break; /* nothing found : store previous solution */
++ }
++
++ /* NOTE:
++ * start[-offset+ZSTD_REP_MOVE-1] is undefined behavior.
++ * (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which
++ * overflows the pointer, which is undefined behavior.
++ */
++ /* catch up */
++ if (offset) {
++ while ((start > anchor) && (start > base + offset - ZSTD_REP_MOVE) &&
++ (start[-1] == (start-offset+ZSTD_REP_MOVE)[-1])) /* only search for offset within prefix */
++ {
++ start--;
++ matchLength++;
++ }
++ offset_2 = offset_1;
++ offset_1 = (U32)(offset - ZSTD_REP_MOVE);
++ }
++
++ /* store sequence */
++_storeSequence:
++ {
++ size_t const litLength = start - anchor;
++ ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength - MINMATCH);
++ anchor = ip = start + matchLength;
++ }
++
++ /* check immediate repcode */
++ while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) {
++ /* store sequence */
++ matchLength = ZSTD_count(ip + EQUAL_READ32, ip + EQUAL_READ32 - offset_2, iend) + EQUAL_READ32;
++ offset = offset_2;
++ offset_2 = offset_1;
++ offset_1 = (U32)offset; /* swap repcodes */
++ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength - MINMATCH);
++ ip += matchLength;
++ anchor = ip;
++ continue; /* faster when present ... (?) */
++ }
++ }
++
++ /* Save reps for next block */
++ ctx->repToConfirm[0] = offset_1 ? offset_1 : savedOffset;
++ ctx->repToConfirm[1] = offset_2 ? offset_2 : savedOffset;
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++static void ZSTD_compressBlock_btlazy2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 1, 2); }
++
++static void ZSTD_compressBlock_lazy2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 2); }
++
++static void ZSTD_compressBlock_lazy(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 1); }
++
++static void ZSTD_compressBlock_greedy(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 0); }
++
++FORCE_INLINE
++void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 searchMethod, const U32 depth)
++{
++ seqStore_t *seqStorePtr = &(ctx->seqStore);
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - 8;
++ const BYTE *const base = ctx->base;
++ const U32 dictLimit = ctx->dictLimit;
++ const U32 lowestIndex = ctx->lowLimit;
++ const BYTE *const prefixStart = base + dictLimit;
++ const BYTE *const dictBase = ctx->dictBase;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const BYTE *const dictStart = dictBase + ctx->lowLimit;
++
++ const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
++ const U32 mls = ctx->params.cParams.searchLength;
++
++ typedef size_t (*searchMax_f)(ZSTD_CCtx * zc, const BYTE *ip, const BYTE *iLimit, size_t *offsetPtr, U32 maxNbAttempts, U32 matchLengthSearch);
++ searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS_extDict : ZSTD_HcFindBestMatch_extDict_selectMLS;
++
++ U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1];
++
++ /* init */
++ ctx->nextToUpdate3 = ctx->nextToUpdate;
++ ip += (ip == prefixStart);
++
++ /* Match Loop */
++ while (ip < ilimit) {
++ size_t matchLength = 0;
++ size_t offset = 0;
++ const BYTE *start = ip + 1;
++ U32 curr = (U32)(ip - base);
++
++ /* check repCode */
++ {
++ const U32 repIndex = (U32)(curr + 1 - offset_1);
++ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *const repMatch = repBase + repIndex;
++ if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
++ if (ZSTD_read32(ip + 1) == ZSTD_read32(repMatch)) {
++ /* repcode detected we should take it */
++ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
++ matchLength =
++ ZSTD_count_2segments(ip + 1 + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
++ if (depth == 0)
++ goto _storeSequence;
++ }
++ }
++
++ /* first search (depth 0) */
++ {
++ size_t offsetFound = 99999999;
++ size_t const ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls);
++ if (ml2 > matchLength)
++ matchLength = ml2, start = ip, offset = offsetFound;
++ }
++
++ if (matchLength < EQUAL_READ32) {
++ ip += ((ip - anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
++ continue;
++ }
++
++ /* let's try to find a better solution */
++ if (depth >= 1)
++ while (ip < ilimit) {
++ ip++;
++ curr++;
++ /* check repCode */
++ if (offset) {
++ const U32 repIndex = (U32)(curr - offset_1);
++ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *const repMatch = repBase + repIndex;
++ if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
++ if (ZSTD_read32(ip) == ZSTD_read32(repMatch)) {
++ /* repcode detected */
++ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
++ size_t const repLength =
++ ZSTD_count_2segments(ip + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repEnd, prefixStart) +
++ EQUAL_READ32;
++ int const gain2 = (int)(repLength * 3);
++ int const gain1 = (int)(matchLength * 3 - ZSTD_highbit32((U32)offset + 1) + 1);
++ if ((repLength >= EQUAL_READ32) && (gain2 > gain1))
++ matchLength = repLength, offset = 0, start = ip;
++ }
++ }
++
++ /* search match, depth 1 */
++ {
++ size_t offset2 = 99999999;
++ size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
++ int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */
++ int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 4);
++ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
++ matchLength = ml2, offset = offset2, start = ip;
++ continue; /* search a better one */
++ }
++ }
++
++ /* let's find an even better one */
++ if ((depth == 2) && (ip < ilimit)) {
++ ip++;
++ curr++;
++ /* check repCode */
++ if (offset) {
++ const U32 repIndex = (U32)(curr - offset_1);
++ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *const repMatch = repBase + repIndex;
++ if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
++ if (ZSTD_read32(ip) == ZSTD_read32(repMatch)) {
++ /* repcode detected */
++ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
++ size_t repLength = ZSTD_count_2segments(ip + EQUAL_READ32, repMatch + EQUAL_READ32, iend,
++ repEnd, prefixStart) +
++ EQUAL_READ32;
++ int gain2 = (int)(repLength * 4);
++ int gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 1);
++ if ((repLength >= EQUAL_READ32) && (gain2 > gain1))
++ matchLength = repLength, offset = 0, start = ip;
++ }
++ }
++
++ /* search match, depth 2 */
++ {
++ size_t offset2 = 99999999;
++ size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
++ int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */
++ int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 7);
++ if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) {
++ matchLength = ml2, offset = offset2, start = ip;
++ continue;
++ }
++ }
++ }
++ break; /* nothing found : store previous solution */
++ }
++
++ /* catch up */
++ if (offset) {
++ U32 const matchIndex = (U32)((start - base) - (offset - ZSTD_REP_MOVE));
++ const BYTE *match = (matchIndex < dictLimit) ? dictBase + matchIndex : base + matchIndex;
++ const BYTE *const mStart = (matchIndex < dictLimit) ? dictStart : prefixStart;
++ while ((start > anchor) && (match > mStart) && (start[-1] == match[-1])) {
++ start--;
++ match--;
++ matchLength++;
++ } /* catch up */
++ offset_2 = offset_1;
++ offset_1 = (U32)(offset - ZSTD_REP_MOVE);
++ }
++
++ /* store sequence */
++ _storeSequence : {
++ size_t const litLength = start - anchor;
++ ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength - MINMATCH);
++ anchor = ip = start + matchLength;
++ }
++
++ /* check immediate repcode */
++ while (ip <= ilimit) {
++ const U32 repIndex = (U32)((ip - base) - offset_2);
++ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *const repMatch = repBase + repIndex;
++ if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
++ if (ZSTD_read32(ip) == ZSTD_read32(repMatch)) {
++ /* repcode detected we should take it */
++ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
++ matchLength =
++ ZSTD_count_2segments(ip + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
++ offset = offset_2;
++ offset_2 = offset_1;
++ offset_1 = (U32)offset; /* swap offset history */
++ ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength - MINMATCH);
++ ip += matchLength;
++ anchor = ip;
++ continue; /* faster when present ... (?) */
++ }
++ break;
++ }
++ }
++
++ /* Save reps for next block */
++ ctx->repToConfirm[0] = offset_1;
++ ctx->repToConfirm[1] = offset_2;
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++void ZSTD_compressBlock_greedy_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 0); }
++
++static void ZSTD_compressBlock_lazy_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 1);
++}
++
++static void ZSTD_compressBlock_lazy2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 2);
++}
++
++static void ZSTD_compressBlock_btlazy2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++ ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 1, 2);
++}
++
++/* The optimal parser */
++#include "zstd_opt.h"
++
++static void ZSTD_compressBlock_btopt(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++#ifdef ZSTD_OPT_H_91842398743
++ ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 0);
++#else
++ (void)ctx;
++ (void)src;
++ (void)srcSize;
++ return;
++#endif
++}
++
++static void ZSTD_compressBlock_btopt2(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++#ifdef ZSTD_OPT_H_91842398743
++ ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 1);
++#else
++ (void)ctx;
++ (void)src;
++ (void)srcSize;
++ return;
++#endif
++}
++
++static void ZSTD_compressBlock_btopt_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++#ifdef ZSTD_OPT_H_91842398743
++ ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 0);
++#else
++ (void)ctx;
++ (void)src;
++ (void)srcSize;
++ return;
++#endif
++}
++
++static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize)
++{
++#ifdef ZSTD_OPT_H_91842398743
++ ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 1);
++#else
++ (void)ctx;
++ (void)src;
++ (void)srcSize;
++ return;
++#endif
++}
++
++typedef void (*ZSTD_blockCompressor)(ZSTD_CCtx *ctx, const void *src, size_t srcSize);
++
++static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
++{
++ static const ZSTD_blockCompressor blockCompressor[2][8] = {
++ {ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy, ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2,
++ ZSTD_compressBlock_btlazy2, ZSTD_compressBlock_btopt, ZSTD_compressBlock_btopt2},
++ {ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict, ZSTD_compressBlock_lazy_extDict,
++ ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict, ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btopt2_extDict}};
++
++ return blockCompressor[extDict][(U32)strat];
++}
++
++static size_t ZSTD_compressBlock_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->params.cParams.strategy, zc->lowLimit < zc->dictLimit);
++ const BYTE *const base = zc->base;
++ const BYTE *const istart = (const BYTE *)src;
++ const U32 curr = (U32)(istart - base);
++ if (srcSize < MIN_CBLOCK_SIZE + ZSTD_blockHeaderSize + 1)
++ return 0; /* don't even attempt compression below a certain srcSize */
++ ZSTD_resetSeqStore(&(zc->seqStore));
++ if (curr > zc->nextToUpdate + 384)
++ zc->nextToUpdate = curr - MIN(192, (U32)(curr - zc->nextToUpdate - 384)); /* update tree not updated after finding very long rep matches */
++ blockCompressor(zc, src, srcSize);
++ return ZSTD_compressSequences(zc, dst, dstCapacity, srcSize);
++}
++
++/*! ZSTD_compress_generic() :
++* Compress a chunk of data into one or multiple blocks.
++* All blocks will be terminated, all input will be consumed.
++* Function will issue an error if there is not enough `dstCapacity` to hold the compressed content.
++* Frame is supposed already started (header already produced)
++* @return : compressed size, or an error code
++*/
++static size_t ZSTD_compress_generic(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, U32 lastFrameChunk)
++{
++ size_t blockSize = cctx->blockSize;
++ size_t remaining = srcSize;
++ const BYTE *ip = (const BYTE *)src;
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *op = ostart;
++ U32 const maxDist = 1 << cctx->params.cParams.windowLog;
++
++ if (cctx->params.fParams.checksumFlag && srcSize)
++ xxh64_update(&cctx->xxhState, src, srcSize);
++
++ while (remaining) {
++ U32 const lastBlock = lastFrameChunk & (blockSize >= remaining);
++ size_t cSize;
++
++ if (dstCapacity < ZSTD_blockHeaderSize + MIN_CBLOCK_SIZE)
++ return ERROR(dstSize_tooSmall); /* not enough space to store compressed block */
++ if (remaining < blockSize)
++ blockSize = remaining;
++
++ /* preemptive overflow correction */
++ if (cctx->lowLimit > (3U << 29)) {
++ U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->params.cParams.hashLog, cctx->params.cParams.strategy)) - 1;
++ U32 const curr = (U32)(ip - cctx->base);
++ U32 const newCurr = (curr & cycleMask) + (1 << cctx->params.cParams.windowLog);
++ U32 const correction = curr - newCurr;
++ ZSTD_STATIC_ASSERT(ZSTD_WINDOWLOG_MAX_64 <= 30);
++ ZSTD_reduceIndex(cctx, correction);
++ cctx->base += correction;
++ cctx->dictBase += correction;
++ cctx->lowLimit -= correction;
++ cctx->dictLimit -= correction;
++ if (cctx->nextToUpdate < correction)
++ cctx->nextToUpdate = 0;
++ else
++ cctx->nextToUpdate -= correction;
++ }
++
++ if ((U32)(ip + blockSize - cctx->base) > cctx->loadedDictEnd + maxDist) {
++ /* enforce maxDist */
++ U32 const newLowLimit = (U32)(ip + blockSize - cctx->base) - maxDist;
++ if (cctx->lowLimit < newLowLimit)
++ cctx->lowLimit = newLowLimit;
++ if (cctx->dictLimit < cctx->lowLimit)
++ cctx->dictLimit = cctx->lowLimit;
++ }
++
++ cSize = ZSTD_compressBlock_internal(cctx, op + ZSTD_blockHeaderSize, dstCapacity - ZSTD_blockHeaderSize, ip, blockSize);
++ if (ZSTD_isError(cSize))
++ return cSize;
++
++ if (cSize == 0) { /* block is not compressible */
++ U32 const cBlockHeader24 = lastBlock + (((U32)bt_raw) << 1) + (U32)(blockSize << 3);
++ if (blockSize + ZSTD_blockHeaderSize > dstCapacity)
++ return ERROR(dstSize_tooSmall);
++ ZSTD_writeLE32(op, cBlockHeader24); /* no pb, 4th byte will be overwritten */
++ memcpy(op + ZSTD_blockHeaderSize, ip, blockSize);
++ cSize = ZSTD_blockHeaderSize + blockSize;
++ } else {
++ U32 const cBlockHeader24 = lastBlock + (((U32)bt_compressed) << 1) + (U32)(cSize << 3);
++ ZSTD_writeLE24(op, cBlockHeader24);
++ cSize += ZSTD_blockHeaderSize;
++ }
++
++ remaining -= blockSize;
++ dstCapacity -= cSize;
++ ip += blockSize;
++ op += cSize;
++ }
++
++ if (lastFrameChunk && (op > ostart))
++ cctx->stage = ZSTDcs_ending;
++ return op - ostart;
++}
++
++static size_t ZSTD_writeFrameHeader(void *dst, size_t dstCapacity, ZSTD_parameters params, U64 pledgedSrcSize, U32 dictID)
++{
++ BYTE *const op = (BYTE *)dst;
++ U32 const dictIDSizeCode = (dictID > 0) + (dictID >= 256) + (dictID >= 65536); /* 0-3 */
++ U32 const checksumFlag = params.fParams.checksumFlag > 0;
++ U32 const windowSize = 1U << params.cParams.windowLog;
++ U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize >= pledgedSrcSize);
++ BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
++ U32 const fcsCode =
++ params.fParams.contentSizeFlag ? (pledgedSrcSize >= 256) + (pledgedSrcSize >= 65536 + 256) + (pledgedSrcSize >= 0xFFFFFFFFU) : 0; /* 0-3 */
++ BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag << 2) + (singleSegment << 5) + (fcsCode << 6));
++ size_t pos;
++
++ if (dstCapacity < ZSTD_frameHeaderSize_max)
++ return ERROR(dstSize_tooSmall);
++
++ ZSTD_writeLE32(dst, ZSTD_MAGICNUMBER);
++ op[4] = frameHeaderDecriptionByte;
++ pos = 5;
++ if (!singleSegment)
++ op[pos++] = windowLogByte;
++ switch (dictIDSizeCode) {
++ default: /* impossible */
++ case 0: break;
++ case 1:
++ op[pos] = (BYTE)(dictID);
++ pos++;
++ break;
++ case 2:
++ ZSTD_writeLE16(op + pos, (U16)dictID);
++ pos += 2;
++ break;
++ case 3:
++ ZSTD_writeLE32(op + pos, dictID);
++ pos += 4;
++ break;
++ }
++ switch (fcsCode) {
++ default: /* impossible */
++ case 0:
++ if (singleSegment)
++ op[pos++] = (BYTE)(pledgedSrcSize);
++ break;
++ case 1:
++ ZSTD_writeLE16(op + pos, (U16)(pledgedSrcSize - 256));
++ pos += 2;
++ break;
++ case 2:
++ ZSTD_writeLE32(op + pos, (U32)(pledgedSrcSize));
++ pos += 4;
++ break;
++ case 3:
++ ZSTD_writeLE64(op + pos, (U64)(pledgedSrcSize));
++ pos += 8;
++ break;
++ }
++ return pos;
++}
++
++static size_t ZSTD_compressContinue_internal(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, U32 frame, U32 lastFrameChunk)
++{
++ const BYTE *const ip = (const BYTE *)src;
++ size_t fhSize = 0;
++
++ if (cctx->stage == ZSTDcs_created)
++ return ERROR(stage_wrong); /* missing init (ZSTD_compressBegin) */
++
++ if (frame && (cctx->stage == ZSTDcs_init)) {
++ fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, cctx->frameContentSize, cctx->dictID);
++ if (ZSTD_isError(fhSize))
++ return fhSize;
++ dstCapacity -= fhSize;
++ dst = (char *)dst + fhSize;
++ cctx->stage = ZSTDcs_ongoing;
++ }
++
++ /* Check if blocks follow each other */
++ if (src != cctx->nextSrc) {
++ /* not contiguous */
++ ptrdiff_t const delta = cctx->nextSrc - ip;
++ cctx->lowLimit = cctx->dictLimit;
++ cctx->dictLimit = (U32)(cctx->nextSrc - cctx->base);
++ cctx->dictBase = cctx->base;
++ cctx->base -= delta;
++ cctx->nextToUpdate = cctx->dictLimit;
++ if (cctx->dictLimit - cctx->lowLimit < HASH_READ_SIZE)
++ cctx->lowLimit = cctx->dictLimit; /* too small extDict */
++ }
++
++ /* if input and dictionary overlap : reduce dictionary (area presumed modified by input) */
++ if ((ip + srcSize > cctx->dictBase + cctx->lowLimit) & (ip < cctx->dictBase + cctx->dictLimit)) {
++ ptrdiff_t const highInputIdx = (ip + srcSize) - cctx->dictBase;
++ U32 const lowLimitMax = (highInputIdx > (ptrdiff_t)cctx->dictLimit) ? cctx->dictLimit : (U32)highInputIdx;
++ cctx->lowLimit = lowLimitMax;
++ }
++
++ cctx->nextSrc = ip + srcSize;
++
++ if (srcSize) {
++ size_t const cSize = frame ? ZSTD_compress_generic(cctx, dst, dstCapacity, src, srcSize, lastFrameChunk)
++ : ZSTD_compressBlock_internal(cctx, dst, dstCapacity, src, srcSize);
++ if (ZSTD_isError(cSize))
++ return cSize;
++ return cSize + fhSize;
++ } else
++ return fhSize;
++}
++
++size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1, 0);
++}
++
++size_t ZSTD_getBlockSizeMax(ZSTD_CCtx *cctx) { return MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, 1 << cctx->params.cParams.windowLog); }
++
++size_t ZSTD_compressBlock(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ size_t const blockSizeMax = ZSTD_getBlockSizeMax(cctx);
++ if (srcSize > blockSizeMax)
++ return ERROR(srcSize_wrong);
++ return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0, 0);
++}
++
++/*! ZSTD_loadDictionaryContent() :
++ * @return : 0, or an error code
++ */
++static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx *zc, const void *src, size_t srcSize)
++{
++ const BYTE *const ip = (const BYTE *)src;
++ const BYTE *const iend = ip + srcSize;
++
++ /* input becomes curr prefix */
++ zc->lowLimit = zc->dictLimit;
++ zc->dictLimit = (U32)(zc->nextSrc - zc->base);
++ zc->dictBase = zc->base;
++ zc->base += ip - zc->nextSrc;
++ zc->nextToUpdate = zc->dictLimit;
++ zc->loadedDictEnd = zc->forceWindow ? 0 : (U32)(iend - zc->base);
++
++ zc->nextSrc = iend;
++ if (srcSize <= HASH_READ_SIZE)
++ return 0;
++
++ switch (zc->params.cParams.strategy) {
++ case ZSTD_fast: ZSTD_fillHashTable(zc, iend, zc->params.cParams.searchLength); break;
++
++ case ZSTD_dfast: ZSTD_fillDoubleHashTable(zc, iend, zc->params.cParams.searchLength); break;
++
++ case ZSTD_greedy:
++ case ZSTD_lazy:
++ case ZSTD_lazy2:
++ if (srcSize >= HASH_READ_SIZE)
++ ZSTD_insertAndFindFirstIndex(zc, iend - HASH_READ_SIZE, zc->params.cParams.searchLength);
++ break;
++
++ case ZSTD_btlazy2:
++ case ZSTD_btopt:
++ case ZSTD_btopt2:
++ if (srcSize >= HASH_READ_SIZE)
++ ZSTD_updateTree(zc, iend - HASH_READ_SIZE, iend, 1 << zc->params.cParams.searchLog, zc->params.cParams.searchLength);
++ break;
++
++ default:
++ return ERROR(GENERIC); /* strategy doesn't exist; impossible */
++ }
++
++ zc->nextToUpdate = (U32)(iend - zc->base);
++ return 0;
++}
++
++/* Dictionaries that assign zero probability to symbols that show up causes problems
++ when FSE encoding. Refuse dictionaries that assign zero probability to symbols
++ that we may encounter during compression.
++ NOTE: This behavior is not standard and could be improved in the future. */
++static size_t ZSTD_checkDictNCount(short *normalizedCounter, unsigned dictMaxSymbolValue, unsigned maxSymbolValue)
++{
++ U32 s;
++ if (dictMaxSymbolValue < maxSymbolValue)
++ return ERROR(dictionary_corrupted);
++ for (s = 0; s <= maxSymbolValue; ++s) {
++ if (normalizedCounter[s] == 0)
++ return ERROR(dictionary_corrupted);
++ }
++ return 0;
++}
++
++/* Dictionary format :
++ * See :
++ * https://github.com/facebook/zstd/blob/master/doc/zstd_compression_format.md#dictionary-format
++ */
++/*! ZSTD_loadZstdDictionary() :
++ * @return : 0, or an error code
++ * assumptions : magic number supposed already checked
++ * dictSize supposed > 8
++ */
++static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx *cctx, const void *dict, size_t dictSize)
++{
++ const BYTE *dictPtr = (const BYTE *)dict;
++ const BYTE *const dictEnd = dictPtr + dictSize;
++ short offcodeNCount[MaxOff + 1];
++ unsigned offcodeMaxValue = MaxOff;
++
++ dictPtr += 4; /* skip magic number */
++ cctx->dictID = cctx->params.fParams.noDictIDFlag ? 0 : ZSTD_readLE32(dictPtr);
++ dictPtr += 4;
++
++ {
++ size_t const hufHeaderSize = HUF_readCTable_wksp(cctx->hufTable, 255, dictPtr, dictEnd - dictPtr, cctx->tmpCounters, sizeof(cctx->tmpCounters));
++ if (HUF_isError(hufHeaderSize))
++ return ERROR(dictionary_corrupted);
++ dictPtr += hufHeaderSize;
++ }
++
++ {
++ unsigned offcodeLog;
++ size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr);
++ if (FSE_isError(offcodeHeaderSize))
++ return ERROR(dictionary_corrupted);
++ if (offcodeLog > OffFSELog)
++ return ERROR(dictionary_corrupted);
++ /* Defer checking offcodeMaxValue because we need to know the size of the dictionary content */
++ CHECK_E(FSE_buildCTable_wksp(cctx->offcodeCTable, offcodeNCount, offcodeMaxValue, offcodeLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)),
++ dictionary_corrupted);
++ dictPtr += offcodeHeaderSize;
++ }
++
++ {
++ short matchlengthNCount[MaxML + 1];
++ unsigned matchlengthMaxValue = MaxML, matchlengthLog;
++ size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr);
++ if (FSE_isError(matchlengthHeaderSize))
++ return ERROR(dictionary_corrupted);
++ if (matchlengthLog > MLFSELog)
++ return ERROR(dictionary_corrupted);
++ /* Every match length code must have non-zero probability */
++ CHECK_F(ZSTD_checkDictNCount(matchlengthNCount, matchlengthMaxValue, MaxML));
++ CHECK_E(
++ FSE_buildCTable_wksp(cctx->matchlengthCTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)),
++ dictionary_corrupted);
++ dictPtr += matchlengthHeaderSize;
++ }
++
++ {
++ short litlengthNCount[MaxLL + 1];
++ unsigned litlengthMaxValue = MaxLL, litlengthLog;
++ size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr);
++ if (FSE_isError(litlengthHeaderSize))
++ return ERROR(dictionary_corrupted);
++ if (litlengthLog > LLFSELog)
++ return ERROR(dictionary_corrupted);
++ /* Every literal length code must have non-zero probability */
++ CHECK_F(ZSTD_checkDictNCount(litlengthNCount, litlengthMaxValue, MaxLL));
++ CHECK_E(FSE_buildCTable_wksp(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)),
++ dictionary_corrupted);
++ dictPtr += litlengthHeaderSize;
++ }
++
++ if (dictPtr + 12 > dictEnd)
++ return ERROR(dictionary_corrupted);
++ cctx->rep[0] = ZSTD_readLE32(dictPtr + 0);
++ cctx->rep[1] = ZSTD_readLE32(dictPtr + 4);
++ cctx->rep[2] = ZSTD_readLE32(dictPtr + 8);
++ dictPtr += 12;
++
++ {
++ size_t const dictContentSize = (size_t)(dictEnd - dictPtr);
++ U32 offcodeMax = MaxOff;
++ if (dictContentSize <= ((U32)-1) - 128 KB) {
++ U32 const maxOffset = (U32)dictContentSize + 128 KB; /* The maximum offset that must be supported */
++ offcodeMax = ZSTD_highbit32(maxOffset); /* Calculate minimum offset code required to represent maxOffset */
++ }
++ /* All offset values <= dictContentSize + 128 KB must be representable */
++ CHECK_F(ZSTD_checkDictNCount(offcodeNCount, offcodeMaxValue, MIN(offcodeMax, MaxOff)));
++ /* All repCodes must be <= dictContentSize and != 0*/
++ {
++ U32 u;
++ for (u = 0; u < 3; u++) {
++ if (cctx->rep[u] == 0)
++ return ERROR(dictionary_corrupted);
++ if (cctx->rep[u] > dictContentSize)
++ return ERROR(dictionary_corrupted);
++ }
++ }
++
++ cctx->flagStaticTables = 1;
++ cctx->flagStaticHufTable = HUF_repeat_valid;
++ return ZSTD_loadDictionaryContent(cctx, dictPtr, dictContentSize);
++ }
++}
++
++/** ZSTD_compress_insertDictionary() :
++* @return : 0, or an error code */
++static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx *cctx, const void *dict, size_t dictSize)
++{
++ if ((dict == NULL) || (dictSize <= 8))
++ return 0;
++
++ /* dict as pure content */
++ if ((ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC) || (cctx->forceRawDict))
++ return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
++
++ /* dict as zstd dictionary */
++ return ZSTD_loadZstdDictionary(cctx, dict, dictSize);
++}
++
++/*! ZSTD_compressBegin_internal() :
++* @return : 0, or an error code */
++static size_t ZSTD_compressBegin_internal(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, ZSTD_parameters params, U64 pledgedSrcSize)
++{
++ ZSTD_compResetPolicy_e const crp = dictSize ? ZSTDcrp_fullReset : ZSTDcrp_continue;
++ CHECK_F(ZSTD_resetCCtx_advanced(cctx, params, pledgedSrcSize, crp));
++ return ZSTD_compress_insertDictionary(cctx, dict, dictSize);
++}
++
++/*! ZSTD_compressBegin_advanced() :
++* @return : 0, or an error code */
++size_t ZSTD_compressBegin_advanced(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize)
++{
++ /* compression parameters verification and optimization */
++ CHECK_F(ZSTD_checkCParams(params.cParams));
++ return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, pledgedSrcSize);
++}
++
++size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, int compressionLevel)
++{
++ ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
++ return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0);
++}
++
++size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel) { return ZSTD_compressBegin_usingDict(cctx, NULL, 0, compressionLevel); }
++
++/*! ZSTD_writeEpilogue() :
++* Ends a frame.
++* @return : nb of bytes written into dst (or an error code) */
++static size_t ZSTD_writeEpilogue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity)
++{
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *op = ostart;
++ size_t fhSize = 0;
++
++ if (cctx->stage == ZSTDcs_created)
++ return ERROR(stage_wrong); /* init missing */
++
++ /* special case : empty frame */
++ if (cctx->stage == ZSTDcs_init) {
++ fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, 0, 0);
++ if (ZSTD_isError(fhSize))
++ return fhSize;
++ dstCapacity -= fhSize;
++ op += fhSize;
++ cctx->stage = ZSTDcs_ongoing;
++ }
++
++ if (cctx->stage != ZSTDcs_ending) {
++ /* write one last empty block, make it the "last" block */
++ U32 const cBlockHeader24 = 1 /* last block */ + (((U32)bt_raw) << 1) + 0;
++ if (dstCapacity < 4)
++ return ERROR(dstSize_tooSmall);
++ ZSTD_writeLE32(op, cBlockHeader24);
++ op += ZSTD_blockHeaderSize;
++ dstCapacity -= ZSTD_blockHeaderSize;
++ }
++
++ if (cctx->params.fParams.checksumFlag) {
++ U32 const checksum = (U32)xxh64_digest(&cctx->xxhState);
++ if (dstCapacity < 4)
++ return ERROR(dstSize_tooSmall);
++ ZSTD_writeLE32(op, checksum);
++ op += 4;
++ }
++
++ cctx->stage = ZSTDcs_created; /* return to "created but no init" status */
++ return op - ostart;
++}
++
++size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ size_t endResult;
++ size_t const cSize = ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1, 1);
++ if (ZSTD_isError(cSize))
++ return cSize;
++ endResult = ZSTD_writeEpilogue(cctx, (char *)dst + cSize, dstCapacity - cSize);
++ if (ZSTD_isError(endResult))
++ return endResult;
++ return cSize + endResult;
++}
++
++static size_t ZSTD_compress_internal(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize,
++ ZSTD_parameters params)
++{
++ CHECK_F(ZSTD_compressBegin_internal(cctx, dict, dictSize, params, srcSize));
++ return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize);
++}
++
++size_t ZSTD_compress_usingDict(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize,
++ ZSTD_parameters params)
++{
++ return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, dict, dictSize, params);
++}
++
++size_t ZSTD_compressCCtx(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, ZSTD_parameters params)
++{
++ return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, NULL, 0, params);
++}
++
++/* ===== Dictionary API ===== */
++
++struct ZSTD_CDict_s {
++ void *dictBuffer;
++ const void *dictContent;
++ size_t dictContentSize;
++ ZSTD_CCtx *refContext;
++}; /* typedef'd tp ZSTD_CDict within "zstd.h" */
++
++size_t ZSTD_CDictWorkspaceBound(ZSTD_compressionParameters cParams) { return ZSTD_CCtxWorkspaceBound(cParams) + ZSTD_ALIGN(sizeof(ZSTD_CDict)); }
++
++static ZSTD_CDict *ZSTD_createCDict_advanced(const void *dictBuffer, size_t dictSize, unsigned byReference, ZSTD_parameters params, ZSTD_customMem customMem)
++{
++ if (!customMem.customAlloc || !customMem.customFree)
++ return NULL;
++
++ {
++ ZSTD_CDict *const cdict = (ZSTD_CDict *)ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
++ ZSTD_CCtx *const cctx = ZSTD_createCCtx_advanced(customMem);
++
++ if (!cdict || !cctx) {
++ ZSTD_free(cdict, customMem);
++ ZSTD_freeCCtx(cctx);
++ return NULL;
++ }
++
++ if ((byReference) || (!dictBuffer) || (!dictSize)) {
++ cdict->dictBuffer = NULL;
++ cdict->dictContent = dictBuffer;
++ } else {
++ void *const internalBuffer = ZSTD_malloc(dictSize, customMem);
++ if (!internalBuffer) {
++ ZSTD_free(cctx, customMem);
++ ZSTD_free(cdict, customMem);
++ return NULL;
++ }
++ memcpy(internalBuffer, dictBuffer, dictSize);
++ cdict->dictBuffer = internalBuffer;
++ cdict->dictContent = internalBuffer;
++ }
++
++ {
++ size_t const errorCode = ZSTD_compressBegin_advanced(cctx, cdict->dictContent, dictSize, params, 0);
++ if (ZSTD_isError(errorCode)) {
++ ZSTD_free(cdict->dictBuffer, customMem);
++ ZSTD_free(cdict, customMem);
++ ZSTD_freeCCtx(cctx);
++ return NULL;
++ }
++ }
++
++ cdict->refContext = cctx;
++ cdict->dictContentSize = dictSize;
++ return cdict;
++ }
++}
++
++ZSTD_CDict *ZSTD_initCDict(const void *dict, size_t dictSize, ZSTD_parameters params, void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
++ return ZSTD_createCDict_advanced(dict, dictSize, 1, params, stackMem);
++}
++
++size_t ZSTD_freeCDict(ZSTD_CDict *cdict)
++{
++ if (cdict == NULL)
++ return 0; /* support free on NULL */
++ {
++ ZSTD_customMem const cMem = cdict->refContext->customMem;
++ ZSTD_freeCCtx(cdict->refContext);
++ ZSTD_free(cdict->dictBuffer, cMem);
++ ZSTD_free(cdict, cMem);
++ return 0;
++ }
++}
++
++static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict *cdict) { return ZSTD_getParamsFromCCtx(cdict->refContext); }
++
++size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict, unsigned long long pledgedSrcSize)
++{
++ if (cdict->dictContentSize)
++ CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize))
++ else {
++ ZSTD_parameters params = cdict->refContext->params;
++ params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
++ CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, params, pledgedSrcSize));
++ }
++ return 0;
++}
++
++/*! ZSTD_compress_usingCDict() :
++* Compression using a digested Dictionary.
++* Faster startup than ZSTD_compress_usingDict(), recommended when same dictionary is used multiple times.
++* Note that compression level is decided during dictionary creation */
++size_t ZSTD_compress_usingCDict(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_CDict *cdict)
++{
++ CHECK_F(ZSTD_compressBegin_usingCDict(cctx, cdict, srcSize));
++
++ if (cdict->refContext->params.fParams.contentSizeFlag == 1) {
++ cctx->params.fParams.contentSizeFlag = 1;
++ cctx->frameContentSize = srcSize;
++ } else {
++ cctx->params.fParams.contentSizeFlag = 0;
++ }
++
++ return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize);
++}
++
++/* ******************************************************************
++* Streaming
++********************************************************************/
++
++typedef enum { zcss_init, zcss_load, zcss_flush, zcss_final } ZSTD_cStreamStage;
++
++struct ZSTD_CStream_s {
++ ZSTD_CCtx *cctx;
++ ZSTD_CDict *cdictLocal;
++ const ZSTD_CDict *cdict;
++ char *inBuff;
++ size_t inBuffSize;
++ size_t inToCompress;
++ size_t inBuffPos;
++ size_t inBuffTarget;
++ size_t blockSize;
++ char *outBuff;
++ size_t outBuffSize;
++ size_t outBuffContentSize;
++ size_t outBuffFlushedSize;
++ ZSTD_cStreamStage stage;
++ U32 checksum;
++ U32 frameEnded;
++ U64 pledgedSrcSize;
++ U64 inputProcessed;
++ ZSTD_parameters params;
++ ZSTD_customMem customMem;
++}; /* typedef'd to ZSTD_CStream within "zstd.h" */
++
++size_t ZSTD_CStreamWorkspaceBound(ZSTD_compressionParameters cParams)
++{
++ size_t const inBuffSize = (size_t)1 << cParams.windowLog;
++ size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, inBuffSize);
++ size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1;
++
++ return ZSTD_CCtxWorkspaceBound(cParams) + ZSTD_ALIGN(sizeof(ZSTD_CStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize);
++}
++
++ZSTD_CStream *ZSTD_createCStream_advanced(ZSTD_customMem customMem)
++{
++ ZSTD_CStream *zcs;
++
++ if (!customMem.customAlloc || !customMem.customFree)
++ return NULL;
++
++ zcs = (ZSTD_CStream *)ZSTD_malloc(sizeof(ZSTD_CStream), customMem);
++ if (zcs == NULL)
++ return NULL;
++ memset(zcs, 0, sizeof(ZSTD_CStream));
++ memcpy(&zcs->customMem, &customMem, sizeof(ZSTD_customMem));
++ zcs->cctx = ZSTD_createCCtx_advanced(customMem);
++ if (zcs->cctx == NULL) {
++ ZSTD_freeCStream(zcs);
++ return NULL;
++ }
++ return zcs;
++}
++
++size_t ZSTD_freeCStream(ZSTD_CStream *zcs)
++{
++ if (zcs == NULL)
++ return 0; /* support free on NULL */
++ {
++ ZSTD_customMem const cMem = zcs->customMem;
++ ZSTD_freeCCtx(zcs->cctx);
++ zcs->cctx = NULL;
++ ZSTD_freeCDict(zcs->cdictLocal);
++ zcs->cdictLocal = NULL;
++ ZSTD_free(zcs->inBuff, cMem);
++ zcs->inBuff = NULL;
++ ZSTD_free(zcs->outBuff, cMem);
++ zcs->outBuff = NULL;
++ ZSTD_free(zcs, cMem);
++ return 0;
++ }
++}
++
++/*====== Initialization ======*/
++
++size_t ZSTD_CStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
++size_t ZSTD_CStreamOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */; }
++
++static size_t ZSTD_resetCStream_internal(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize)
++{
++ if (zcs->inBuffSize == 0)
++ return ERROR(stage_wrong); /* zcs has not been init at least once => can't reset */
++
++ if (zcs->cdict)
++ CHECK_F(ZSTD_compressBegin_usingCDict(zcs->cctx, zcs->cdict, pledgedSrcSize))
++ else
++ CHECK_F(ZSTD_compressBegin_advanced(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize));
++
++ zcs->inToCompress = 0;
++ zcs->inBuffPos = 0;
++ zcs->inBuffTarget = zcs->blockSize;
++ zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
++ zcs->stage = zcss_load;
++ zcs->frameEnded = 0;
++ zcs->pledgedSrcSize = pledgedSrcSize;
++ zcs->inputProcessed = 0;
++ return 0; /* ready to go */
++}
++
++size_t ZSTD_resetCStream(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize)
++{
++
++ zcs->params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
++
++ return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
++}
++
++static size_t ZSTD_initCStream_advanced(ZSTD_CStream *zcs, const void *dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize)
++{
++ /* allocate buffers */
++ {
++ size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog;
++ if (zcs->inBuffSize < neededInBuffSize) {
++ zcs->inBuffSize = neededInBuffSize;
++ ZSTD_free(zcs->inBuff, zcs->customMem);
++ zcs->inBuff = (char *)ZSTD_malloc(neededInBuffSize, zcs->customMem);
++ if (zcs->inBuff == NULL)
++ return ERROR(memory_allocation);
++ }
++ zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize);
++ }
++ if (zcs->outBuffSize < ZSTD_compressBound(zcs->blockSize) + 1) {
++ zcs->outBuffSize = ZSTD_compressBound(zcs->blockSize) + 1;
++ ZSTD_free(zcs->outBuff, zcs->customMem);
++ zcs->outBuff = (char *)ZSTD_malloc(zcs->outBuffSize, zcs->customMem);
++ if (zcs->outBuff == NULL)
++ return ERROR(memory_allocation);
++ }
++
++ if (dict && dictSize >= 8) {
++ ZSTD_freeCDict(zcs->cdictLocal);
++ zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, 0, params, zcs->customMem);
++ if (zcs->cdictLocal == NULL)
++ return ERROR(memory_allocation);
++ zcs->cdict = zcs->cdictLocal;
++ } else
++ zcs->cdict = NULL;
++
++ zcs->checksum = params.fParams.checksumFlag > 0;
++ zcs->params = params;
++
++ return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
++}
++
++ZSTD_CStream *ZSTD_initCStream(ZSTD_parameters params, unsigned long long pledgedSrcSize, void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
++ ZSTD_CStream *const zcs = ZSTD_createCStream_advanced(stackMem);
++ if (zcs) {
++ size_t const code = ZSTD_initCStream_advanced(zcs, NULL, 0, params, pledgedSrcSize);
++ if (ZSTD_isError(code)) {
++ return NULL;
++ }
++ }
++ return zcs;
++}
++
++ZSTD_CStream *ZSTD_initCStream_usingCDict(const ZSTD_CDict *cdict, unsigned long long pledgedSrcSize, void *workspace, size_t workspaceSize)
++{
++ ZSTD_parameters const params = ZSTD_getParamsFromCDict(cdict);
++ ZSTD_CStream *const zcs = ZSTD_initCStream(params, pledgedSrcSize, workspace, workspaceSize);
++ if (zcs) {
++ zcs->cdict = cdict;
++ if (ZSTD_isError(ZSTD_resetCStream_internal(zcs, pledgedSrcSize))) {
++ return NULL;
++ }
++ }
++ return zcs;
++}
++
++/*====== Compression ======*/
++
++typedef enum { zsf_gather, zsf_flush, zsf_end } ZSTD_flush_e;
++
++ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ size_t const length = MIN(dstCapacity, srcSize);
++ memcpy(dst, src, length);
++ return length;
++}
++
++static size_t ZSTD_compressStream_generic(ZSTD_CStream *zcs, void *dst, size_t *dstCapacityPtr, const void *src, size_t *srcSizePtr, ZSTD_flush_e const flush)
++{
++ U32 someMoreWork = 1;
++ const char *const istart = (const char *)src;
++ const char *const iend = istart + *srcSizePtr;
++ const char *ip = istart;
++ char *const ostart = (char *)dst;
++ char *const oend = ostart + *dstCapacityPtr;
++ char *op = ostart;
++
++ while (someMoreWork) {
++ switch (zcs->stage) {
++ case zcss_init:
++ return ERROR(init_missing); /* call ZBUFF_compressInit() first ! */
++
++ case zcss_load:
++ /* complete inBuffer */
++ {
++ size_t const toLoad = zcs->inBuffTarget - zcs->inBuffPos;
++ size_t const loaded = ZSTD_limitCopy(zcs->inBuff + zcs->inBuffPos, toLoad, ip, iend - ip);
++ zcs->inBuffPos += loaded;
++ ip += loaded;
++ if ((zcs->inBuffPos == zcs->inToCompress) || (!flush && (toLoad != loaded))) {
++ someMoreWork = 0;
++ break; /* not enough input to get a full block : stop there, wait for more */
++ }
++ }
++ /* compress curr block (note : this stage cannot be stopped in the middle) */
++ {
++ void *cDst;
++ size_t cSize;
++ size_t const iSize = zcs->inBuffPos - zcs->inToCompress;
++ size_t oSize = oend - op;
++ if (oSize >= ZSTD_compressBound(iSize))
++ cDst = op; /* compress directly into output buffer (avoid flush stage) */
++ else
++ cDst = zcs->outBuff, oSize = zcs->outBuffSize;
++ cSize = (flush == zsf_end) ? ZSTD_compressEnd(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize)
++ : ZSTD_compressContinue(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize);
++ if (ZSTD_isError(cSize))
++ return cSize;
++ if (flush == zsf_end)
++ zcs->frameEnded = 1;
++ /* prepare next block */
++ zcs->inBuffTarget = zcs->inBuffPos + zcs->blockSize;
++ if (zcs->inBuffTarget > zcs->inBuffSize)
++ zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize; /* note : inBuffSize >= blockSize */
++ zcs->inToCompress = zcs->inBuffPos;
++ if (cDst == op) {
++ op += cSize;
++ break;
++ } /* no need to flush */
++ zcs->outBuffContentSize = cSize;
++ zcs->outBuffFlushedSize = 0;
++ zcs->stage = zcss_flush; /* pass-through to flush stage */
++ }
++
++ case zcss_flush: {
++ size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
++ size_t const flushed = ZSTD_limitCopy(op, oend - op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
++ op += flushed;
++ zcs->outBuffFlushedSize += flushed;
++ if (toFlush != flushed) {
++ someMoreWork = 0;
++ break;
++ } /* dst too small to store flushed data : stop there */
++ zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
++ zcs->stage = zcss_load;
++ break;
++ }
++
++ case zcss_final:
++ someMoreWork = 0; /* do nothing */
++ break;
++
++ default:
++ return ERROR(GENERIC); /* impossible */
++ }
++ }
++
++ *srcSizePtr = ip - istart;
++ *dstCapacityPtr = op - ostart;
++ zcs->inputProcessed += *srcSizePtr;
++ if (zcs->frameEnded)
++ return 0;
++ {
++ size_t hintInSize = zcs->inBuffTarget - zcs->inBuffPos;
++ if (hintInSize == 0)
++ hintInSize = zcs->blockSize;
++ return hintInSize;
++ }
++}
++
++size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output, ZSTD_inBuffer *input)
++{
++ size_t sizeRead = input->size - input->pos;
++ size_t sizeWritten = output->size - output->pos;
++ size_t const result =
++ ZSTD_compressStream_generic(zcs, (char *)(output->dst) + output->pos, &sizeWritten, (const char *)(input->src) + input->pos, &sizeRead, zsf_gather);
++ input->pos += sizeRead;
++ output->pos += sizeWritten;
++ return result;
++}
++
++/*====== Finalize ======*/
++
++/*! ZSTD_flushStream() :
++* @return : amount of data remaining to flush */
++size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output)
++{
++ size_t srcSize = 0;
++ size_t sizeWritten = output->size - output->pos;
++ size_t const result = ZSTD_compressStream_generic(zcs, (char *)(output->dst) + output->pos, &sizeWritten, &srcSize,
++ &srcSize, /* use a valid src address instead of NULL */
++ zsf_flush);
++ output->pos += sizeWritten;
++ if (ZSTD_isError(result))
++ return result;
++ return zcs->outBuffContentSize - zcs->outBuffFlushedSize; /* remaining to flush */
++}
++
++size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output)
++{
++ BYTE *const ostart = (BYTE *)(output->dst) + output->pos;
++ BYTE *const oend = (BYTE *)(output->dst) + output->size;
++ BYTE *op = ostart;
++
++ if ((zcs->pledgedSrcSize) && (zcs->inputProcessed != zcs->pledgedSrcSize))
++ return ERROR(srcSize_wrong); /* pledgedSrcSize not respected */
++
++ if (zcs->stage != zcss_final) {
++ /* flush whatever remains */
++ size_t srcSize = 0;
++ size_t sizeWritten = output->size - output->pos;
++ size_t const notEnded =
++ ZSTD_compressStream_generic(zcs, ostart, &sizeWritten, &srcSize, &srcSize, zsf_end); /* use a valid src address instead of NULL */
++ size_t const remainingToFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
++ op += sizeWritten;
++ if (remainingToFlush) {
++ output->pos += sizeWritten;
++ return remainingToFlush + ZSTD_BLOCKHEADERSIZE /* final empty block */ + (zcs->checksum * 4);
++ }
++ /* create epilogue */
++ zcs->stage = zcss_final;
++ zcs->outBuffContentSize = !notEnded ? 0 : ZSTD_compressEnd(zcs->cctx, zcs->outBuff, zcs->outBuffSize, NULL,
++ 0); /* write epilogue, including final empty block, into outBuff */
++ }
++
++ /* flush epilogue */
++ {
++ size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
++ size_t const flushed = ZSTD_limitCopy(op, oend - op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
++ op += flushed;
++ zcs->outBuffFlushedSize += flushed;
++ output->pos += op - ostart;
++ if (toFlush == flushed)
++ zcs->stage = zcss_init; /* end reached */
++ return toFlush - flushed;
++ }
++}
++
++/*-===== Pre-defined compression levels =====-*/
++
++#define ZSTD_DEFAULT_CLEVEL 1
++#define ZSTD_MAX_CLEVEL 22
++int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; }
++
++static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL + 1] = {
++ {
++ /* "default" */
++ /* W, C, H, S, L, TL, strat */
++ {18, 12, 12, 1, 7, 16, ZSTD_fast}, /* level 0 - never used */
++ {19, 13, 14, 1, 7, 16, ZSTD_fast}, /* level 1 */
++ {19, 15, 16, 1, 6, 16, ZSTD_fast}, /* level 2 */
++ {20, 16, 17, 1, 5, 16, ZSTD_dfast}, /* level 3.*/
++ {20, 18, 18, 1, 5, 16, ZSTD_dfast}, /* level 4.*/
++ {20, 15, 18, 3, 5, 16, ZSTD_greedy}, /* level 5 */
++ {21, 16, 19, 2, 5, 16, ZSTD_lazy}, /* level 6 */
++ {21, 17, 20, 3, 5, 16, ZSTD_lazy}, /* level 7 */
++ {21, 18, 20, 3, 5, 16, ZSTD_lazy2}, /* level 8 */
++ {21, 20, 20, 3, 5, 16, ZSTD_lazy2}, /* level 9 */
++ {21, 19, 21, 4, 5, 16, ZSTD_lazy2}, /* level 10 */
++ {22, 20, 22, 4, 5, 16, ZSTD_lazy2}, /* level 11 */
++ {22, 20, 22, 5, 5, 16, ZSTD_lazy2}, /* level 12 */
++ {22, 21, 22, 5, 5, 16, ZSTD_lazy2}, /* level 13 */
++ {22, 21, 22, 6, 5, 16, ZSTD_lazy2}, /* level 14 */
++ {22, 21, 21, 5, 5, 16, ZSTD_btlazy2}, /* level 15 */
++ {23, 22, 22, 5, 5, 16, ZSTD_btlazy2}, /* level 16 */
++ {23, 21, 22, 4, 5, 24, ZSTD_btopt}, /* level 17 */
++ {23, 23, 22, 6, 5, 32, ZSTD_btopt}, /* level 18 */
++ {23, 23, 22, 6, 3, 48, ZSTD_btopt}, /* level 19 */
++ {25, 25, 23, 7, 3, 64, ZSTD_btopt2}, /* level 20 */
++ {26, 26, 23, 7, 3, 256, ZSTD_btopt2}, /* level 21 */
++ {27, 27, 25, 9, 3, 512, ZSTD_btopt2}, /* level 22 */
++ },
++ {
++ /* for srcSize <= 256 KB */
++ /* W, C, H, S, L, T, strat */
++ {0, 0, 0, 0, 0, 0, ZSTD_fast}, /* level 0 - not used */
++ {18, 13, 14, 1, 6, 8, ZSTD_fast}, /* level 1 */
++ {18, 14, 13, 1, 5, 8, ZSTD_dfast}, /* level 2 */
++ {18, 16, 15, 1, 5, 8, ZSTD_dfast}, /* level 3 */
++ {18, 15, 17, 1, 5, 8, ZSTD_greedy}, /* level 4.*/
++ {18, 16, 17, 4, 5, 8, ZSTD_greedy}, /* level 5.*/
++ {18, 16, 17, 3, 5, 8, ZSTD_lazy}, /* level 6.*/
++ {18, 17, 17, 4, 4, 8, ZSTD_lazy}, /* level 7 */
++ {18, 17, 17, 4, 4, 8, ZSTD_lazy2}, /* level 8 */
++ {18, 17, 17, 5, 4, 8, ZSTD_lazy2}, /* level 9 */
++ {18, 17, 17, 6, 4, 8, ZSTD_lazy2}, /* level 10 */
++ {18, 18, 17, 6, 4, 8, ZSTD_lazy2}, /* level 11.*/
++ {18, 18, 17, 7, 4, 8, ZSTD_lazy2}, /* level 12.*/
++ {18, 19, 17, 6, 4, 8, ZSTD_btlazy2}, /* level 13 */
++ {18, 18, 18, 4, 4, 16, ZSTD_btopt}, /* level 14.*/
++ {18, 18, 18, 4, 3, 16, ZSTD_btopt}, /* level 15.*/
++ {18, 19, 18, 6, 3, 32, ZSTD_btopt}, /* level 16.*/
++ {18, 19, 18, 8, 3, 64, ZSTD_btopt}, /* level 17.*/
++ {18, 19, 18, 9, 3, 128, ZSTD_btopt}, /* level 18.*/
++ {18, 19, 18, 10, 3, 256, ZSTD_btopt}, /* level 19.*/
++ {18, 19, 18, 11, 3, 512, ZSTD_btopt2}, /* level 20.*/
++ {18, 19, 18, 12, 3, 512, ZSTD_btopt2}, /* level 21.*/
++ {18, 19, 18, 13, 3, 512, ZSTD_btopt2}, /* level 22.*/
++ },
++ {
++ /* for srcSize <= 128 KB */
++ /* W, C, H, S, L, T, strat */
++ {17, 12, 12, 1, 7, 8, ZSTD_fast}, /* level 0 - not used */
++ {17, 12, 13, 1, 6, 8, ZSTD_fast}, /* level 1 */
++ {17, 13, 16, 1, 5, 8, ZSTD_fast}, /* level 2 */
++ {17, 16, 16, 2, 5, 8, ZSTD_dfast}, /* level 3 */
++ {17, 13, 15, 3, 4, 8, ZSTD_greedy}, /* level 4 */
++ {17, 15, 17, 4, 4, 8, ZSTD_greedy}, /* level 5 */
++ {17, 16, 17, 3, 4, 8, ZSTD_lazy}, /* level 6 */
++ {17, 15, 17, 4, 4, 8, ZSTD_lazy2}, /* level 7 */
++ {17, 17, 17, 4, 4, 8, ZSTD_lazy2}, /* level 8 */
++ {17, 17, 17, 5, 4, 8, ZSTD_lazy2}, /* level 9 */
++ {17, 17, 17, 6, 4, 8, ZSTD_lazy2}, /* level 10 */
++ {17, 17, 17, 7, 4, 8, ZSTD_lazy2}, /* level 11 */
++ {17, 17, 17, 8, 4, 8, ZSTD_lazy2}, /* level 12 */
++ {17, 18, 17, 6, 4, 8, ZSTD_btlazy2}, /* level 13.*/
++ {17, 17, 17, 7, 3, 8, ZSTD_btopt}, /* level 14.*/
++ {17, 17, 17, 7, 3, 16, ZSTD_btopt}, /* level 15.*/
++ {17, 18, 17, 7, 3, 32, ZSTD_btopt}, /* level 16.*/
++ {17, 18, 17, 7, 3, 64, ZSTD_btopt}, /* level 17.*/
++ {17, 18, 17, 7, 3, 256, ZSTD_btopt}, /* level 18.*/
++ {17, 18, 17, 8, 3, 256, ZSTD_btopt}, /* level 19.*/
++ {17, 18, 17, 9, 3, 256, ZSTD_btopt2}, /* level 20.*/
++ {17, 18, 17, 10, 3, 256, ZSTD_btopt2}, /* level 21.*/
++ {17, 18, 17, 11, 3, 512, ZSTD_btopt2}, /* level 22.*/
++ },
++ {
++ /* for srcSize <= 16 KB */
++ /* W, C, H, S, L, T, strat */
++ {14, 12, 12, 1, 7, 6, ZSTD_fast}, /* level 0 - not used */
++ {14, 14, 14, 1, 6, 6, ZSTD_fast}, /* level 1 */
++ {14, 14, 14, 1, 4, 6, ZSTD_fast}, /* level 2 */
++ {14, 14, 14, 1, 4, 6, ZSTD_dfast}, /* level 3.*/
++ {14, 14, 14, 4, 4, 6, ZSTD_greedy}, /* level 4.*/
++ {14, 14, 14, 3, 4, 6, ZSTD_lazy}, /* level 5.*/
++ {14, 14, 14, 4, 4, 6, ZSTD_lazy2}, /* level 6 */
++ {14, 14, 14, 5, 4, 6, ZSTD_lazy2}, /* level 7 */
++ {14, 14, 14, 6, 4, 6, ZSTD_lazy2}, /* level 8.*/
++ {14, 15, 14, 6, 4, 6, ZSTD_btlazy2}, /* level 9.*/
++ {14, 15, 14, 3, 3, 6, ZSTD_btopt}, /* level 10.*/
++ {14, 15, 14, 6, 3, 8, ZSTD_btopt}, /* level 11.*/
++ {14, 15, 14, 6, 3, 16, ZSTD_btopt}, /* level 12.*/
++ {14, 15, 14, 6, 3, 24, ZSTD_btopt}, /* level 13.*/
++ {14, 15, 15, 6, 3, 48, ZSTD_btopt}, /* level 14.*/
++ {14, 15, 15, 6, 3, 64, ZSTD_btopt}, /* level 15.*/
++ {14, 15, 15, 6, 3, 96, ZSTD_btopt}, /* level 16.*/
++ {14, 15, 15, 6, 3, 128, ZSTD_btopt}, /* level 17.*/
++ {14, 15, 15, 6, 3, 256, ZSTD_btopt}, /* level 18.*/
++ {14, 15, 15, 7, 3, 256, ZSTD_btopt}, /* level 19.*/
++ {14, 15, 15, 8, 3, 256, ZSTD_btopt2}, /* level 20.*/
++ {14, 15, 15, 9, 3, 256, ZSTD_btopt2}, /* level 21.*/
++ {14, 15, 15, 10, 3, 256, ZSTD_btopt2}, /* level 22.*/
++ },
++};
++
++/*! ZSTD_getCParams() :
++* @return ZSTD_compressionParameters structure for a selected compression level, `srcSize` and `dictSize`.
++* Size values are optional, provide 0 if not known or unused */
++ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSize, size_t dictSize)
++{
++ ZSTD_compressionParameters cp;
++ size_t const addedSize = srcSize ? 0 : 500;
++ U64 const rSize = srcSize + dictSize ? srcSize + dictSize + addedSize : (U64)-1;
++ U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB); /* intentional underflow for srcSizeHint == 0 */
++ if (compressionLevel <= 0)
++ compressionLevel = ZSTD_DEFAULT_CLEVEL; /* 0 == default; no negative compressionLevel yet */
++ if (compressionLevel > ZSTD_MAX_CLEVEL)
++ compressionLevel = ZSTD_MAX_CLEVEL;
++ cp = ZSTD_defaultCParameters[tableID][compressionLevel];
++ if (ZSTD_32bits()) { /* auto-correction, for 32-bits mode */
++ if (cp.windowLog > ZSTD_WINDOWLOG_MAX)
++ cp.windowLog = ZSTD_WINDOWLOG_MAX;
++ if (cp.chainLog > ZSTD_CHAINLOG_MAX)
++ cp.chainLog = ZSTD_CHAINLOG_MAX;
++ if (cp.hashLog > ZSTD_HASHLOG_MAX)
++ cp.hashLog = ZSTD_HASHLOG_MAX;
++ }
++ cp = ZSTD_adjustCParams(cp, srcSize, dictSize);
++ return cp;
++}
++
++/*! ZSTD_getParams() :
++* same as ZSTD_getCParams(), but @return a `ZSTD_parameters` object (instead of `ZSTD_compressionParameters`).
++* All fields of `ZSTD_frameParameters` are set to default (0) */
++ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSize, size_t dictSize)
++{
++ ZSTD_parameters params;
++ ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSize, dictSize);
++ memset(&params, 0, sizeof(params));
++ params.cParams = cParams;
++ return params;
++}
++
++EXPORT_SYMBOL(ZSTD_maxCLevel);
++EXPORT_SYMBOL(ZSTD_compressBound);
++
++EXPORT_SYMBOL(ZSTD_CCtxWorkspaceBound);
++EXPORT_SYMBOL(ZSTD_initCCtx);
++EXPORT_SYMBOL(ZSTD_compressCCtx);
++EXPORT_SYMBOL(ZSTD_compress_usingDict);
++
++EXPORT_SYMBOL(ZSTD_CDictWorkspaceBound);
++EXPORT_SYMBOL(ZSTD_initCDict);
++EXPORT_SYMBOL(ZSTD_compress_usingCDict);
++
++EXPORT_SYMBOL(ZSTD_CStreamWorkspaceBound);
++EXPORT_SYMBOL(ZSTD_initCStream);
++EXPORT_SYMBOL(ZSTD_initCStream_usingCDict);
++EXPORT_SYMBOL(ZSTD_resetCStream);
++EXPORT_SYMBOL(ZSTD_compressStream);
++EXPORT_SYMBOL(ZSTD_flushStream);
++EXPORT_SYMBOL(ZSTD_endStream);
++EXPORT_SYMBOL(ZSTD_CStreamInSize);
++EXPORT_SYMBOL(ZSTD_CStreamOutSize);
++
++EXPORT_SYMBOL(ZSTD_getCParams);
++EXPORT_SYMBOL(ZSTD_getParams);
++EXPORT_SYMBOL(ZSTD_checkCParams);
++EXPORT_SYMBOL(ZSTD_adjustCParams);
++
++EXPORT_SYMBOL(ZSTD_compressBegin);
++EXPORT_SYMBOL(ZSTD_compressBegin_usingDict);
++EXPORT_SYMBOL(ZSTD_compressBegin_advanced);
++EXPORT_SYMBOL(ZSTD_copyCCtx);
++EXPORT_SYMBOL(ZSTD_compressBegin_usingCDict);
++EXPORT_SYMBOL(ZSTD_compressContinue);
++EXPORT_SYMBOL(ZSTD_compressEnd);
++
++EXPORT_SYMBOL(ZSTD_getBlockSizeMax);
++EXPORT_SYMBOL(ZSTD_compressBlock);
++
++MODULE_LICENSE("Dual BSD/GPL");
++MODULE_DESCRIPTION("Zstd Compressor");
+diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
+new file mode 100644
+index 0000000..72df4828
+--- /dev/null
++++ b/lib/zstd/decompress.c
+@@ -0,0 +1,2526 @@
++/**
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++/* ***************************************************************
++* Tuning parameters
++*****************************************************************/
++/*!
++* MAXWINDOWSIZE_DEFAULT :
++* maximum window size accepted by DStream, by default.
++* Frames requiring more memory will be rejected.
++*/
++#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT
++#define ZSTD_MAXWINDOWSIZE_DEFAULT ((1 << ZSTD_WINDOWLOG_MAX) + 1) /* defined within zstd.h */
++#endif
++
++/*-*******************************************************
++* Dependencies
++*********************************************************/
++#include "fse.h"
++#include "huf.h"
++#include "mem.h" /* low level memory routines */
++#include "zstd_internal.h"
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/string.h> /* memcpy, memmove, memset */
++
++#define ZSTD_PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0)
++
++/*-*************************************
++* Macros
++***************************************/
++#define ZSTD_isError ERR_isError /* for inlining */
++#define FSE_isError ERR_isError
++#define HUF_isError ERR_isError
++
++/*_*******************************************************
++* Memory operations
++**********************************************************/
++static void ZSTD_copy4(void *dst, const void *src) { memcpy(dst, src, 4); }
++
++/*-*************************************************************
++* Context management
++***************************************************************/
++typedef enum {
++ ZSTDds_getFrameHeaderSize,
++ ZSTDds_decodeFrameHeader,
++ ZSTDds_decodeBlockHeader,
++ ZSTDds_decompressBlock,
++ ZSTDds_decompressLastBlock,
++ ZSTDds_checkChecksum,
++ ZSTDds_decodeSkippableHeader,
++ ZSTDds_skipFrame
++} ZSTD_dStage;
++
++typedef struct {
++ FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)];
++ FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)];
++ FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)];
++ HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */
++ U64 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32 / 2];
++ U32 rep[ZSTD_REP_NUM];
++} ZSTD_entropyTables_t;
++
++struct ZSTD_DCtx_s {
++ const FSE_DTable *LLTptr;
++ const FSE_DTable *MLTptr;
++ const FSE_DTable *OFTptr;
++ const HUF_DTable *HUFptr;
++ ZSTD_entropyTables_t entropy;
++ const void *previousDstEnd; /* detect continuity */
++ const void *base; /* start of curr segment */
++ const void *vBase; /* virtual start of previous segment if it was just before curr one */
++ const void *dictEnd; /* end of previous segment */
++ size_t expected;
++ ZSTD_frameParams fParams;
++ blockType_e bType; /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */
++ ZSTD_dStage stage;
++ U32 litEntropy;
++ U32 fseEntropy;
++ struct xxh64_state xxhState;
++ size_t headerSize;
++ U32 dictID;
++ const BYTE *litPtr;
++ ZSTD_customMem customMem;
++ size_t litSize;
++ size_t rleSize;
++ BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH];
++ BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
++}; /* typedef'd to ZSTD_DCtx within "zstd.h" */
++
++size_t ZSTD_DCtxWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DCtx)); }
++
++size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx)
++{
++ dctx->expected = ZSTD_frameHeaderSize_prefix;
++ dctx->stage = ZSTDds_getFrameHeaderSize;
++ dctx->previousDstEnd = NULL;
++ dctx->base = NULL;
++ dctx->vBase = NULL;
++ dctx->dictEnd = NULL;
++ dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */
++ dctx->litEntropy = dctx->fseEntropy = 0;
++ dctx->dictID = 0;
++ ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue));
++ memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */
++ dctx->LLTptr = dctx->entropy.LLTable;
++ dctx->MLTptr = dctx->entropy.MLTable;
++ dctx->OFTptr = dctx->entropy.OFTable;
++ dctx->HUFptr = dctx->entropy.hufTable;
++ return 0;
++}
++
++ZSTD_DCtx *ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
++{
++ ZSTD_DCtx *dctx;
++
++ if (!customMem.customAlloc || !customMem.customFree)
++ return NULL;
++
++ dctx = (ZSTD_DCtx *)ZSTD_malloc(sizeof(ZSTD_DCtx), customMem);
++ if (!dctx)
++ return NULL;
++ memcpy(&dctx->customMem, &customMem, sizeof(customMem));
++ ZSTD_decompressBegin(dctx);
++ return dctx;
++}
++
++ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
++ return ZSTD_createDCtx_advanced(stackMem);
++}
++
++size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx)
++{
++ if (dctx == NULL)
++ return 0; /* support free on NULL */
++ ZSTD_free(dctx, dctx->customMem);
++ return 0; /* reserved as a potential error code in the future */
++}
++
++void ZSTD_copyDCtx(ZSTD_DCtx *dstDCtx, const ZSTD_DCtx *srcDCtx)
++{
++ size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max;
++ memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize); /* no need to copy workspace */
++}
++
++static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict);
++
++/*-*************************************************************
++* Decompression section
++***************************************************************/
++
++/*! ZSTD_isFrame() :
++ * Tells if the content of `buffer` starts with a valid Frame Identifier.
++ * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0.
++ * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled.
++ * Note 3 : Skippable Frame Identifiers are considered valid. */
++unsigned ZSTD_isFrame(const void *buffer, size_t size)
++{
++ if (size < 4)
++ return 0;
++ {
++ U32 const magic = ZSTD_readLE32(buffer);
++ if (magic == ZSTD_MAGICNUMBER)
++ return 1;
++ if ((magic & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START)
++ return 1;
++ }
++ return 0;
++}
++
++/** ZSTD_frameHeaderSize() :
++* srcSize must be >= ZSTD_frameHeaderSize_prefix.
++* @return : size of the Frame Header */
++static size_t ZSTD_frameHeaderSize(const void *src, size_t srcSize)
++{
++ if (srcSize < ZSTD_frameHeaderSize_prefix)
++ return ERROR(srcSize_wrong);
++ {
++ BYTE const fhd = ((const BYTE *)src)[4];
++ U32 const dictID = fhd & 3;
++ U32 const singleSegment = (fhd >> 5) & 1;
++ U32 const fcsId = fhd >> 6;
++ return ZSTD_frameHeaderSize_prefix + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] + (singleSegment && !fcsId);
++ }
++}
++
++/** ZSTD_getFrameParams() :
++* decode Frame Header, or require larger `srcSize`.
++* @return : 0, `fparamsPtr` is correctly filled,
++* >0, `srcSize` is too small, result is expected `srcSize`,
++* or an error code, which can be tested using ZSTD_isError() */
++size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src, size_t srcSize)
++{
++ const BYTE *ip = (const BYTE *)src;
++
++ if (srcSize < ZSTD_frameHeaderSize_prefix)
++ return ZSTD_frameHeaderSize_prefix;
++ if (ZSTD_readLE32(src) != ZSTD_MAGICNUMBER) {
++ if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
++ if (srcSize < ZSTD_skippableHeaderSize)
++ return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */
++ memset(fparamsPtr, 0, sizeof(*fparamsPtr));
++ fparamsPtr->frameContentSize = ZSTD_readLE32((const char *)src + 4);
++ fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */
++ return 0;
++ }
++ return ERROR(prefix_unknown);
++ }
++
++ /* ensure there is enough `srcSize` to fully read/decode frame header */
++ {
++ size_t const fhsize = ZSTD_frameHeaderSize(src, srcSize);
++ if (srcSize < fhsize)
++ return fhsize;
++ }
++
++ {
++ BYTE const fhdByte = ip[4];
++ size_t pos = 5;
++ U32 const dictIDSizeCode = fhdByte & 3;
++ U32 const checksumFlag = (fhdByte >> 2) & 1;
++ U32 const singleSegment = (fhdByte >> 5) & 1;
++ U32 const fcsID = fhdByte >> 6;
++ U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX;
++ U32 windowSize = 0;
++ U32 dictID = 0;
++ U64 frameContentSize = 0;
++ if ((fhdByte & 0x08) != 0)
++ return ERROR(frameParameter_unsupported); /* reserved bits, which must be zero */
++ if (!singleSegment) {
++ BYTE const wlByte = ip[pos++];
++ U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
++ if (windowLog > ZSTD_WINDOWLOG_MAX)
++ return ERROR(frameParameter_windowTooLarge); /* avoids issue with 1 << windowLog */
++ windowSize = (1U << windowLog);
++ windowSize += (windowSize >> 3) * (wlByte & 7);
++ }
++
++ switch (dictIDSizeCode) {
++ default: /* impossible */
++ case 0: break;
++ case 1:
++ dictID = ip[pos];
++ pos++;
++ break;
++ case 2:
++ dictID = ZSTD_readLE16(ip + pos);
++ pos += 2;
++ break;
++ case 3:
++ dictID = ZSTD_readLE32(ip + pos);
++ pos += 4;
++ break;
++ }
++ switch (fcsID) {
++ default: /* impossible */
++ case 0:
++ if (singleSegment)
++ frameContentSize = ip[pos];
++ break;
++ case 1: frameContentSize = ZSTD_readLE16(ip + pos) + 256; break;
++ case 2: frameContentSize = ZSTD_readLE32(ip + pos); break;
++ case 3: frameContentSize = ZSTD_readLE64(ip + pos); break;
++ }
++ if (!windowSize)
++ windowSize = (U32)frameContentSize;
++ if (windowSize > windowSizeMax)
++ return ERROR(frameParameter_windowTooLarge);
++ fparamsPtr->frameContentSize = frameContentSize;
++ fparamsPtr->windowSize = windowSize;
++ fparamsPtr->dictID = dictID;
++ fparamsPtr->checksumFlag = checksumFlag;
++ }
++ return 0;
++}
++
++/** ZSTD_getFrameContentSize() :
++* compatible with legacy mode
++* @return : decompressed size of the single frame pointed to be `src` if known, otherwise
++* - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
++* - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */
++unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize)
++{
++ {
++ ZSTD_frameParams fParams;
++ if (ZSTD_getFrameParams(&fParams, src, srcSize) != 0)
++ return ZSTD_CONTENTSIZE_ERROR;
++ if (fParams.windowSize == 0) {
++ /* Either skippable or empty frame, size == 0 either way */
++ return 0;
++ } else if (fParams.frameContentSize != 0) {
++ return fParams.frameContentSize;
++ } else {
++ return ZSTD_CONTENTSIZE_UNKNOWN;
++ }
++ }
++}
++
++/** ZSTD_findDecompressedSize() :
++ * compatible with legacy mode
++ * `srcSize` must be the exact length of some number of ZSTD compressed and/or
++ * skippable frames
++ * @return : decompressed size of the frames contained */
++unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize)
++{
++ {
++ unsigned long long totalDstSize = 0;
++ while (srcSize >= ZSTD_frameHeaderSize_prefix) {
++ const U32 magicNumber = ZSTD_readLE32(src);
++
++ if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
++ size_t skippableSize;
++ if (srcSize < ZSTD_skippableHeaderSize)
++ return ERROR(srcSize_wrong);
++ skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize;
++ if (srcSize < skippableSize) {
++ return ZSTD_CONTENTSIZE_ERROR;
++ }
++
++ src = (const BYTE *)src + skippableSize;
++ srcSize -= skippableSize;
++ continue;
++ }
++
++ {
++ unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
++ if (ret >= ZSTD_CONTENTSIZE_ERROR)
++ return ret;
++
++ /* check for overflow */
++ if (totalDstSize + ret < totalDstSize)
++ return ZSTD_CONTENTSIZE_ERROR;
++ totalDstSize += ret;
++ }
++ {
++ size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize);
++ if (ZSTD_isError(frameSrcSize)) {
++ return ZSTD_CONTENTSIZE_ERROR;
++ }
++
++ src = (const BYTE *)src + frameSrcSize;
++ srcSize -= frameSrcSize;
++ }
++ }
++
++ if (srcSize) {
++ return ZSTD_CONTENTSIZE_ERROR;
++ }
++
++ return totalDstSize;
++ }
++}
++
++/** ZSTD_decodeFrameHeader() :
++* `headerSize` must be the size provided by ZSTD_frameHeaderSize().
++* @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */
++static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx *dctx, const void *src, size_t headerSize)
++{
++ size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, headerSize);
++ if (ZSTD_isError(result))
++ return result; /* invalid header */
++ if (result > 0)
++ return ERROR(srcSize_wrong); /* headerSize too small */
++ if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID))
++ return ERROR(dictionary_wrong);
++ if (dctx->fParams.checksumFlag)
++ xxh64_reset(&dctx->xxhState, 0);
++ return 0;
++}
++
++typedef struct {
++ blockType_e blockType;
++ U32 lastBlock;
++ U32 origSize;
++} blockProperties_t;
++
++/*! ZSTD_getcBlockSize() :
++* Provides the size of compressed block from block header `src` */
++size_t ZSTD_getcBlockSize(const void *src, size_t srcSize, blockProperties_t *bpPtr)
++{
++ if (srcSize < ZSTD_blockHeaderSize)
++ return ERROR(srcSize_wrong);
++ {
++ U32 const cBlockHeader = ZSTD_readLE24(src);
++ U32 const cSize = cBlockHeader >> 3;
++ bpPtr->lastBlock = cBlockHeader & 1;
++ bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3);
++ bpPtr->origSize = cSize; /* only useful for RLE */
++ if (bpPtr->blockType == bt_rle)
++ return 1;
++ if (bpPtr->blockType == bt_reserved)
++ return ERROR(corruption_detected);
++ return cSize;
++ }
++}
++
++static size_t ZSTD_copyRawBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ if (srcSize > dstCapacity)
++ return ERROR(dstSize_tooSmall);
++ memcpy(dst, src, srcSize);
++ return srcSize;
++}
++
++static size_t ZSTD_setRleBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize, size_t regenSize)
++{
++ if (srcSize != 1)
++ return ERROR(srcSize_wrong);
++ if (regenSize > dstCapacity)
++ return ERROR(dstSize_tooSmall);
++ memset(dst, *(const BYTE *)src, regenSize);
++ return regenSize;
++}
++
++/*! ZSTD_decodeLiteralsBlock() :
++ @return : nb of bytes read from src (< srcSize ) */
++size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx *dctx, const void *src, size_t srcSize) /* note : srcSize < BLOCKSIZE */
++{
++ if (srcSize < MIN_CBLOCK_SIZE)
++ return ERROR(corruption_detected);
++
++ {
++ const BYTE *const istart = (const BYTE *)src;
++ symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3);
++
++ switch (litEncType) {
++ case set_repeat:
++ if (dctx->litEntropy == 0)
++ return ERROR(dictionary_corrupted);
++ /* fall-through */
++ case set_compressed:
++ if (srcSize < 5)
++ return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */
++ {
++ size_t lhSize, litSize, litCSize;
++ U32 singleStream = 0;
++ U32 const lhlCode = (istart[0] >> 2) & 3;
++ U32 const lhc = ZSTD_readLE32(istart);
++ switch (lhlCode) {
++ case 0:
++ case 1:
++ default: /* note : default is impossible, since lhlCode into [0..3] */
++ /* 2 - 2 - 10 - 10 */
++ singleStream = !lhlCode;
++ lhSize = 3;
++ litSize = (lhc >> 4) & 0x3FF;
++ litCSize = (lhc >> 14) & 0x3FF;
++ break;
++ case 2:
++ /* 2 - 2 - 14 - 14 */
++ lhSize = 4;
++ litSize = (lhc >> 4) & 0x3FFF;
++ litCSize = lhc >> 18;
++ break;
++ case 3:
++ /* 2 - 2 - 18 - 18 */
++ lhSize = 5;
++ litSize = (lhc >> 4) & 0x3FFFF;
++ litCSize = (lhc >> 22) + (istart[4] << 10);
++ break;
++ }
++ if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX)
++ return ERROR(corruption_detected);
++ if (litCSize + lhSize > srcSize)
++ return ERROR(corruption_detected);
++
++ if (HUF_isError(
++ (litEncType == set_repeat)
++ ? (singleStream ? HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr)
++ : HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr))
++ : (singleStream
++ ? HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize,
++ dctx->entropy.workspace, sizeof(dctx->entropy.workspace))
++ : HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize,
++ dctx->entropy.workspace, sizeof(dctx->entropy.workspace)))))
++ return ERROR(corruption_detected);
++
++ dctx->litPtr = dctx->litBuffer;
++ dctx->litSize = litSize;
++ dctx->litEntropy = 1;
++ if (litEncType == set_compressed)
++ dctx->HUFptr = dctx->entropy.hufTable;
++ memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
++ return litCSize + lhSize;
++ }
++
++ case set_basic: {
++ size_t litSize, lhSize;
++ U32 const lhlCode = ((istart[0]) >> 2) & 3;
++ switch (lhlCode) {
++ case 0:
++ case 2:
++ default: /* note : default is impossible, since lhlCode into [0..3] */
++ lhSize = 1;
++ litSize = istart[0] >> 3;
++ break;
++ case 1:
++ lhSize = 2;
++ litSize = ZSTD_readLE16(istart) >> 4;
++ break;
++ case 3:
++ lhSize = 3;
++ litSize = ZSTD_readLE24(istart) >> 4;
++ break;
++ }
++
++ if (lhSize + litSize + WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */
++ if (litSize + lhSize > srcSize)
++ return ERROR(corruption_detected);
++ memcpy(dctx->litBuffer, istart + lhSize, litSize);
++ dctx->litPtr = dctx->litBuffer;
++ dctx->litSize = litSize;
++ memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
++ return lhSize + litSize;
++ }
++ /* direct reference into compressed stream */
++ dctx->litPtr = istart + lhSize;
++ dctx->litSize = litSize;
++ return lhSize + litSize;
++ }
++
++ case set_rle: {
++ U32 const lhlCode = ((istart[0]) >> 2) & 3;
++ size_t litSize, lhSize;
++ switch (lhlCode) {
++ case 0:
++ case 2:
++ default: /* note : default is impossible, since lhlCode into [0..3] */
++ lhSize = 1;
++ litSize = istart[0] >> 3;
++ break;
++ case 1:
++ lhSize = 2;
++ litSize = ZSTD_readLE16(istart) >> 4;
++ break;
++ case 3:
++ lhSize = 3;
++ litSize = ZSTD_readLE24(istart) >> 4;
++ if (srcSize < 4)
++ return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */
++ break;
++ }
++ if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX)
++ return ERROR(corruption_detected);
++ memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH);
++ dctx->litPtr = dctx->litBuffer;
++ dctx->litSize = litSize;
++ return lhSize + 1;
++ }
++ default:
++ return ERROR(corruption_detected); /* impossible */
++ }
++ }
++}
++
++typedef union {
++ FSE_decode_t realData;
++ U32 alignedBy4;
++} FSE_decode_t4;
++
++static const FSE_decode_t4 LL_defaultDTable[(1 << LL_DEFAULTNORMLOG) + 1] = {
++ {{LL_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */
++ {{0, 0, 4}}, /* 0 : base, symbol, bits */
++ {{16, 0, 4}},
++ {{32, 1, 5}},
++ {{0, 3, 5}},
++ {{0, 4, 5}},
++ {{0, 6, 5}},
++ {{0, 7, 5}},
++ {{0, 9, 5}},
++ {{0, 10, 5}},
++ {{0, 12, 5}},
++ {{0, 14, 6}},
++ {{0, 16, 5}},
++ {{0, 18, 5}},
++ {{0, 19, 5}},
++ {{0, 21, 5}},
++ {{0, 22, 5}},
++ {{0, 24, 5}},
++ {{32, 25, 5}},
++ {{0, 26, 5}},
++ {{0, 27, 6}},
++ {{0, 29, 6}},
++ {{0, 31, 6}},
++ {{32, 0, 4}},
++ {{0, 1, 4}},
++ {{0, 2, 5}},
++ {{32, 4, 5}},
++ {{0, 5, 5}},
++ {{32, 7, 5}},
++ {{0, 8, 5}},
++ {{32, 10, 5}},
++ {{0, 11, 5}},
++ {{0, 13, 6}},
++ {{32, 16, 5}},
++ {{0, 17, 5}},
++ {{32, 19, 5}},
++ {{0, 20, 5}},
++ {{32, 22, 5}},
++ {{0, 23, 5}},
++ {{0, 25, 4}},
++ {{16, 25, 4}},
++ {{32, 26, 5}},
++ {{0, 28, 6}},
++ {{0, 30, 6}},
++ {{48, 0, 4}},
++ {{16, 1, 4}},
++ {{32, 2, 5}},
++ {{32, 3, 5}},
++ {{32, 5, 5}},
++ {{32, 6, 5}},
++ {{32, 8, 5}},
++ {{32, 9, 5}},
++ {{32, 11, 5}},
++ {{32, 12, 5}},
++ {{0, 15, 6}},
++ {{32, 17, 5}},
++ {{32, 18, 5}},
++ {{32, 20, 5}},
++ {{32, 21, 5}},
++ {{32, 23, 5}},
++ {{32, 24, 5}},
++ {{0, 35, 6}},
++ {{0, 34, 6}},
++ {{0, 33, 6}},
++ {{0, 32, 6}},
++}; /* LL_defaultDTable */
++
++static const FSE_decode_t4 ML_defaultDTable[(1 << ML_DEFAULTNORMLOG) + 1] = {
++ {{ML_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */
++ {{0, 0, 6}}, /* 0 : base, symbol, bits */
++ {{0, 1, 4}},
++ {{32, 2, 5}},
++ {{0, 3, 5}},
++ {{0, 5, 5}},
++ {{0, 6, 5}},
++ {{0, 8, 5}},
++ {{0, 10, 6}},
++ {{0, 13, 6}},
++ {{0, 16, 6}},
++ {{0, 19, 6}},
++ {{0, 22, 6}},
++ {{0, 25, 6}},
++ {{0, 28, 6}},
++ {{0, 31, 6}},
++ {{0, 33, 6}},
++ {{0, 35, 6}},
++ {{0, 37, 6}},
++ {{0, 39, 6}},
++ {{0, 41, 6}},
++ {{0, 43, 6}},
++ {{0, 45, 6}},
++ {{16, 1, 4}},
++ {{0, 2, 4}},
++ {{32, 3, 5}},
++ {{0, 4, 5}},
++ {{32, 6, 5}},
++ {{0, 7, 5}},
++ {{0, 9, 6}},
++ {{0, 12, 6}},
++ {{0, 15, 6}},
++ {{0, 18, 6}},
++ {{0, 21, 6}},
++ {{0, 24, 6}},
++ {{0, 27, 6}},
++ {{0, 30, 6}},
++ {{0, 32, 6}},
++ {{0, 34, 6}},
++ {{0, 36, 6}},
++ {{0, 38, 6}},
++ {{0, 40, 6}},
++ {{0, 42, 6}},
++ {{0, 44, 6}},
++ {{32, 1, 4}},
++ {{48, 1, 4}},
++ {{16, 2, 4}},
++ {{32, 4, 5}},
++ {{32, 5, 5}},
++ {{32, 7, 5}},
++ {{32, 8, 5}},
++ {{0, 11, 6}},
++ {{0, 14, 6}},
++ {{0, 17, 6}},
++ {{0, 20, 6}},
++ {{0, 23, 6}},
++ {{0, 26, 6}},
++ {{0, 29, 6}},
++ {{0, 52, 6}},
++ {{0, 51, 6}},
++ {{0, 50, 6}},
++ {{0, 49, 6}},
++ {{0, 48, 6}},
++ {{0, 47, 6}},
++ {{0, 46, 6}},
++}; /* ML_defaultDTable */
++
++static const FSE_decode_t4 OF_defaultDTable[(1 << OF_DEFAULTNORMLOG) + 1] = {
++ {{OF_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */
++ {{0, 0, 5}}, /* 0 : base, symbol, bits */
++ {{0, 6, 4}},
++ {{0, 9, 5}},
++ {{0, 15, 5}},
++ {{0, 21, 5}},
++ {{0, 3, 5}},
++ {{0, 7, 4}},
++ {{0, 12, 5}},
++ {{0, 18, 5}},
++ {{0, 23, 5}},
++ {{0, 5, 5}},
++ {{0, 8, 4}},
++ {{0, 14, 5}},
++ {{0, 20, 5}},
++ {{0, 2, 5}},
++ {{16, 7, 4}},
++ {{0, 11, 5}},
++ {{0, 17, 5}},
++ {{0, 22, 5}},
++ {{0, 4, 5}},
++ {{16, 8, 4}},
++ {{0, 13, 5}},
++ {{0, 19, 5}},
++ {{0, 1, 5}},
++ {{16, 6, 4}},
++ {{0, 10, 5}},
++ {{0, 16, 5}},
++ {{0, 28, 5}},
++ {{0, 27, 5}},
++ {{0, 26, 5}},
++ {{0, 25, 5}},
++ {{0, 24, 5}},
++}; /* OF_defaultDTable */
++
++/*! ZSTD_buildSeqTable() :
++ @return : nb bytes read from src,
++ or an error code if it fails, testable with ZSTD_isError()
++*/
++static size_t ZSTD_buildSeqTable(FSE_DTable *DTableSpace, const FSE_DTable **DTablePtr, symbolEncodingType_e type, U32 max, U32 maxLog, const void *src,
++ size_t srcSize, const FSE_decode_t4 *defaultTable, U32 flagRepeatTable, void *workspace, size_t workspaceSize)
++{
++ const void *const tmpPtr = defaultTable; /* bypass strict aliasing */
++ switch (type) {
++ case set_rle:
++ if (!srcSize)
++ return ERROR(srcSize_wrong);
++ if ((*(const BYTE *)src) > max)
++ return ERROR(corruption_detected);
++ FSE_buildDTable_rle(DTableSpace, *(const BYTE *)src);
++ *DTablePtr = DTableSpace;
++ return 1;
++ case set_basic: *DTablePtr = (const FSE_DTable *)tmpPtr; return 0;
++ case set_repeat:
++ if (!flagRepeatTable)
++ return ERROR(corruption_detected);
++ return 0;
++ default: /* impossible */
++ case set_compressed: {
++ U32 tableLog;
++ S16 *norm = (S16 *)workspace;
++ size_t const spaceUsed32 = ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(GENERIC);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++ {
++ size_t const headerSize = FSE_readNCount(norm, &max, &tableLog, src, srcSize);
++ if (FSE_isError(headerSize))
++ return ERROR(corruption_detected);
++ if (tableLog > maxLog)
++ return ERROR(corruption_detected);
++ FSE_buildDTable_wksp(DTableSpace, norm, max, tableLog, workspace, workspaceSize);
++ *DTablePtr = DTableSpace;
++ return headerSize;
++ }
++ }
++ }
++}
++
++size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx *dctx, int *nbSeqPtr, const void *src, size_t srcSize)
++{
++ const BYTE *const istart = (const BYTE *const)src;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *ip = istart;
++
++ /* check */
++ if (srcSize < MIN_SEQUENCES_SIZE)
++ return ERROR(srcSize_wrong);
++
++ /* SeqHead */
++ {
++ int nbSeq = *ip++;
++ if (!nbSeq) {
++ *nbSeqPtr = 0;
++ return 1;
++ }
++ if (nbSeq > 0x7F) {
++ if (nbSeq == 0xFF) {
++ if (ip + 2 > iend)
++ return ERROR(srcSize_wrong);
++ nbSeq = ZSTD_readLE16(ip) + LONGNBSEQ, ip += 2;
++ } else {
++ if (ip >= iend)
++ return ERROR(srcSize_wrong);
++ nbSeq = ((nbSeq - 0x80) << 8) + *ip++;
++ }
++ }
++ *nbSeqPtr = nbSeq;
++ }
++
++ /* FSE table descriptors */
++ if (ip + 4 > iend)
++ return ERROR(srcSize_wrong); /* minimum possible size */
++ {
++ symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6);
++ symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3);
++ symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3);
++ ip++;
++
++ /* Build DTables */
++ {
++ size_t const llhSize = ZSTD_buildSeqTable(dctx->entropy.LLTable, &dctx->LLTptr, LLtype, MaxLL, LLFSELog, ip, iend - ip,
++ LL_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace));
++ if (ZSTD_isError(llhSize))
++ return ERROR(corruption_detected);
++ ip += llhSize;
++ }
++ {
++ size_t const ofhSize = ZSTD_buildSeqTable(dctx->entropy.OFTable, &dctx->OFTptr, OFtype, MaxOff, OffFSELog, ip, iend - ip,
++ OF_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace));
++ if (ZSTD_isError(ofhSize))
++ return ERROR(corruption_detected);
++ ip += ofhSize;
++ }
++ {
++ size_t const mlhSize = ZSTD_buildSeqTable(dctx->entropy.MLTable, &dctx->MLTptr, MLtype, MaxML, MLFSELog, ip, iend - ip,
++ ML_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace));
++ if (ZSTD_isError(mlhSize))
++ return ERROR(corruption_detected);
++ ip += mlhSize;
++ }
++ }
++
++ return ip - istart;
++}
++
++typedef struct {
++ size_t litLength;
++ size_t matchLength;
++ size_t offset;
++ const BYTE *match;
++} seq_t;
++
++typedef struct {
++ BIT_DStream_t DStream;
++ FSE_DState_t stateLL;
++ FSE_DState_t stateOffb;
++ FSE_DState_t stateML;
++ size_t prevOffset[ZSTD_REP_NUM];
++ const BYTE *base;
++ size_t pos;
++ uPtrDiff gotoDict;
++} seqState_t;
++
++FORCE_NOINLINE
++size_t ZSTD_execSequenceLast7(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base,
++ const BYTE *const vBase, const BYTE *const dictEnd)
++{
++ BYTE *const oLitEnd = op + sequence.litLength;
++ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
++ BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */
++ BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH;
++ const BYTE *const iLitEnd = *litPtr + sequence.litLength;
++ const BYTE *match = oLitEnd - sequence.offset;
++
++ /* check */
++ if (oMatchEnd > oend)
++ return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */
++ if (iLitEnd > litLimit)
++ return ERROR(corruption_detected); /* over-read beyond lit buffer */
++ if (oLitEnd <= oend_w)
++ return ERROR(GENERIC); /* Precondition */
++
++ /* copy literals */
++ if (op < oend_w) {
++ ZSTD_wildcopy(op, *litPtr, oend_w - op);
++ *litPtr += oend_w - op;
++ op = oend_w;
++ }
++ while (op < oLitEnd)
++ *op++ = *(*litPtr)++;
++
++ /* copy Match */
++ if (sequence.offset > (size_t)(oLitEnd - base)) {
++ /* offset beyond prefix */
++ if (sequence.offset > (size_t)(oLitEnd - vBase))
++ return ERROR(corruption_detected);
++ match = dictEnd - (base - match);
++ if (match + sequence.matchLength <= dictEnd) {
++ memmove(oLitEnd, match, sequence.matchLength);
++ return sequenceLength;
++ }
++ /* span extDict & currPrefixSegment */
++ {
++ size_t const length1 = dictEnd - match;
++ memmove(oLitEnd, match, length1);
++ op = oLitEnd + length1;
++ sequence.matchLength -= length1;
++ match = base;
++ }
++ }
++ while (op < oMatchEnd)
++ *op++ = *match++;
++ return sequenceLength;
++}
++
++static seq_t ZSTD_decodeSequence(seqState_t *seqState)
++{
++ seq_t seq;
++
++ U32 const llCode = FSE_peekSymbol(&seqState->stateLL);
++ U32 const mlCode = FSE_peekSymbol(&seqState->stateML);
++ U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */
++
++ U32 const llBits = LL_bits[llCode];
++ U32 const mlBits = ML_bits[mlCode];
++ U32 const ofBits = ofCode;
++ U32 const totalBits = llBits + mlBits + ofBits;
++
++ static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18,
++ 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000};
++
++ static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
++ 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41,
++ 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003};
++
++ static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD,
++ 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD,
++ 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD};
++
++ /* sequence */
++ {
++ size_t offset;
++ if (!ofCode)
++ offset = 0;
++ else {
++ offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
++ if (ZSTD_32bits())
++ BIT_reloadDStream(&seqState->DStream);
++ }
++
++ if (ofCode <= 1) {
++ offset += (llCode == 0);
++ if (offset) {
++ size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
++ temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
++ if (offset != 1)
++ seqState->prevOffset[2] = seqState->prevOffset[1];
++ seqState->prevOffset[1] = seqState->prevOffset[0];
++ seqState->prevOffset[0] = offset = temp;
++ } else {
++ offset = seqState->prevOffset[0];
++ }
++ } else {
++ seqState->prevOffset[2] = seqState->prevOffset[1];
++ seqState->prevOffset[1] = seqState->prevOffset[0];
++ seqState->prevOffset[0] = offset;
++ }
++ seq.offset = offset;
++ }
++
++ seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */
++ if (ZSTD_32bits() && (mlBits + llBits > 24))
++ BIT_reloadDStream(&seqState->DStream);
++
++ seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */
++ if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog)))
++ BIT_reloadDStream(&seqState->DStream);
++
++ /* ANS state update */
++ FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */
++ FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */
++ if (ZSTD_32bits())
++ BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
++ FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
++
++ seq.match = NULL;
++
++ return seq;
++}
++
++FORCE_INLINE
++size_t ZSTD_execSequence(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base,
++ const BYTE *const vBase, const BYTE *const dictEnd)
++{
++ BYTE *const oLitEnd = op + sequence.litLength;
++ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
++ BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */
++ BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH;
++ const BYTE *const iLitEnd = *litPtr + sequence.litLength;
++ const BYTE *match = oLitEnd - sequence.offset;
++
++ /* check */
++ if (oMatchEnd > oend)
++ return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */
++ if (iLitEnd > litLimit)
++ return ERROR(corruption_detected); /* over-read beyond lit buffer */
++ if (oLitEnd > oend_w)
++ return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd);
++
++ /* copy Literals */
++ ZSTD_copy8(op, *litPtr);
++ if (sequence.litLength > 8)
++ ZSTD_wildcopy(op + 8, (*litPtr) + 8,
++ sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */
++ op = oLitEnd;
++ *litPtr = iLitEnd; /* update for next sequence */
++
++ /* copy Match */
++ if (sequence.offset > (size_t)(oLitEnd - base)) {
++ /* offset beyond prefix */
++ if (sequence.offset > (size_t)(oLitEnd - vBase))
++ return ERROR(corruption_detected);
++ match = dictEnd + (match - base);
++ if (match + sequence.matchLength <= dictEnd) {
++ memmove(oLitEnd, match, sequence.matchLength);
++ return sequenceLength;
++ }
++ /* span extDict & currPrefixSegment */
++ {
++ size_t const length1 = dictEnd - match;
++ memmove(oLitEnd, match, length1);
++ op = oLitEnd + length1;
++ sequence.matchLength -= length1;
++ match = base;
++ if (op > oend_w || sequence.matchLength < MINMATCH) {
++ U32 i;
++ for (i = 0; i < sequence.matchLength; ++i)
++ op[i] = match[i];
++ return sequenceLength;
++ }
++ }
++ }
++ /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */
++
++ /* match within prefix */
++ if (sequence.offset < 8) {
++ /* close range match, overlap */
++ static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */
++ static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */
++ int const sub2 = dec64table[sequence.offset];
++ op[0] = match[0];
++ op[1] = match[1];
++ op[2] = match[2];
++ op[3] = match[3];
++ match += dec32table[sequence.offset];
++ ZSTD_copy4(op + 4, match);
++ match -= sub2;
++ } else {
++ ZSTD_copy8(op, match);
++ }
++ op += 8;
++ match += 8;
++
++ if (oMatchEnd > oend - (16 - MINMATCH)) {
++ if (op < oend_w) {
++ ZSTD_wildcopy(op, match, oend_w - op);
++ match += oend_w - op;
++ op = oend_w;
++ }
++ while (op < oMatchEnd)
++ *op++ = *match++;
++ } else {
++ ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */
++ }
++ return sequenceLength;
++}
++
++static size_t ZSTD_decompressSequences(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize)
++{
++ const BYTE *ip = (const BYTE *)seqStart;
++ const BYTE *const iend = ip + seqSize;
++ BYTE *const ostart = (BYTE * const)dst;
++ BYTE *const oend = ostart + maxDstSize;
++ BYTE *op = ostart;
++ const BYTE *litPtr = dctx->litPtr;
++ const BYTE *const litEnd = litPtr + dctx->litSize;
++ const BYTE *const base = (const BYTE *)(dctx->base);
++ const BYTE *const vBase = (const BYTE *)(dctx->vBase);
++ const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd);
++ int nbSeq;
++
++ /* Build Decoding Tables */
++ {
++ size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize);
++ if (ZSTD_isError(seqHSize))
++ return seqHSize;
++ ip += seqHSize;
++ }
++
++ /* Regen sequences */
++ if (nbSeq) {
++ seqState_t seqState;
++ dctx->fseEntropy = 1;
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ seqState.prevOffset[i] = dctx->entropy.rep[i];
++ }
++ CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected);
++ FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr);
++ FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr);
++ FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr);
++
++ for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq;) {
++ nbSeq--;
++ {
++ seq_t const sequence = ZSTD_decodeSequence(&seqState);
++ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd);
++ if (ZSTD_isError(oneSeqSize))
++ return oneSeqSize;
++ op += oneSeqSize;
++ }
++ }
++
++ /* check if reached exact end */
++ if (nbSeq)
++ return ERROR(corruption_detected);
++ /* save reps for next block */
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]);
++ }
++ }
++
++ /* last literal segment */
++ {
++ size_t const lastLLSize = litEnd - litPtr;
++ if (lastLLSize > (size_t)(oend - op))
++ return ERROR(dstSize_tooSmall);
++ memcpy(op, litPtr, lastLLSize);
++ op += lastLLSize;
++ }
++
++ return op - ostart;
++}
++
++FORCE_INLINE seq_t ZSTD_decodeSequenceLong_generic(seqState_t *seqState, int const longOffsets)
++{
++ seq_t seq;
++
++ U32 const llCode = FSE_peekSymbol(&seqState->stateLL);
++ U32 const mlCode = FSE_peekSymbol(&seqState->stateML);
++ U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */
++
++ U32 const llBits = LL_bits[llCode];
++ U32 const mlBits = ML_bits[mlCode];
++ U32 const ofBits = ofCode;
++ U32 const totalBits = llBits + mlBits + ofBits;
++
++ static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18,
++ 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000};
++
++ static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
++ 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41,
++ 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003};
++
++ static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD,
++ 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD,
++ 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD};
++
++ /* sequence */
++ {
++ size_t offset;
++ if (!ofCode)
++ offset = 0;
++ else {
++ if (longOffsets) {
++ int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN);
++ offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
++ if (ZSTD_32bits() || extraBits)
++ BIT_reloadDStream(&seqState->DStream);
++ if (extraBits)
++ offset += BIT_readBitsFast(&seqState->DStream, extraBits);
++ } else {
++ offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
++ if (ZSTD_32bits())
++ BIT_reloadDStream(&seqState->DStream);
++ }
++ }
++
++ if (ofCode <= 1) {
++ offset += (llCode == 0);
++ if (offset) {
++ size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
++ temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
++ if (offset != 1)
++ seqState->prevOffset[2] = seqState->prevOffset[1];
++ seqState->prevOffset[1] = seqState->prevOffset[0];
++ seqState->prevOffset[0] = offset = temp;
++ } else {
++ offset = seqState->prevOffset[0];
++ }
++ } else {
++ seqState->prevOffset[2] = seqState->prevOffset[1];
++ seqState->prevOffset[1] = seqState->prevOffset[0];
++ seqState->prevOffset[0] = offset;
++ }
++ seq.offset = offset;
++ }
++
++ seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */
++ if (ZSTD_32bits() && (mlBits + llBits > 24))
++ BIT_reloadDStream(&seqState->DStream);
++
++ seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */
++ if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog)))
++ BIT_reloadDStream(&seqState->DStream);
++
++ {
++ size_t const pos = seqState->pos + seq.litLength;
++ seq.match = seqState->base + pos - seq.offset; /* single memory segment */
++ if (seq.offset > pos)
++ seq.match += seqState->gotoDict; /* separate memory segment */
++ seqState->pos = pos + seq.matchLength;
++ }
++
++ /* ANS state update */
++ FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */
++ FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */
++ if (ZSTD_32bits())
++ BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
++ FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
++
++ return seq;
++}
++
++static seq_t ZSTD_decodeSequenceLong(seqState_t *seqState, unsigned const windowSize)
++{
++ if (ZSTD_highbit32(windowSize) > STREAM_ACCUMULATOR_MIN) {
++ return ZSTD_decodeSequenceLong_generic(seqState, 1);
++ } else {
++ return ZSTD_decodeSequenceLong_generic(seqState, 0);
++ }
++}
++
++FORCE_INLINE
++size_t ZSTD_execSequenceLong(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base,
++ const BYTE *const vBase, const BYTE *const dictEnd)
++{
++ BYTE *const oLitEnd = op + sequence.litLength;
++ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
++ BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */
++ BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH;
++ const BYTE *const iLitEnd = *litPtr + sequence.litLength;
++ const BYTE *match = sequence.match;
++
++ /* check */
++ if (oMatchEnd > oend)
++ return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */
++ if (iLitEnd > litLimit)
++ return ERROR(corruption_detected); /* over-read beyond lit buffer */
++ if (oLitEnd > oend_w)
++ return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd);
++
++ /* copy Literals */
++ ZSTD_copy8(op, *litPtr);
++ if (sequence.litLength > 8)
++ ZSTD_wildcopy(op + 8, (*litPtr) + 8,
++ sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */
++ op = oLitEnd;
++ *litPtr = iLitEnd; /* update for next sequence */
++
++ /* copy Match */
++ if (sequence.offset > (size_t)(oLitEnd - base)) {
++ /* offset beyond prefix */
++ if (sequence.offset > (size_t)(oLitEnd - vBase))
++ return ERROR(corruption_detected);
++ if (match + sequence.matchLength <= dictEnd) {
++ memmove(oLitEnd, match, sequence.matchLength);
++ return sequenceLength;
++ }
++ /* span extDict & currPrefixSegment */
++ {
++ size_t const length1 = dictEnd - match;
++ memmove(oLitEnd, match, length1);
++ op = oLitEnd + length1;
++ sequence.matchLength -= length1;
++ match = base;
++ if (op > oend_w || sequence.matchLength < MINMATCH) {
++ U32 i;
++ for (i = 0; i < sequence.matchLength; ++i)
++ op[i] = match[i];
++ return sequenceLength;
++ }
++ }
++ }
++ /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */
++
++ /* match within prefix */
++ if (sequence.offset < 8) {
++ /* close range match, overlap */
++ static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */
++ static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */
++ int const sub2 = dec64table[sequence.offset];
++ op[0] = match[0];
++ op[1] = match[1];
++ op[2] = match[2];
++ op[3] = match[3];
++ match += dec32table[sequence.offset];
++ ZSTD_copy4(op + 4, match);
++ match -= sub2;
++ } else {
++ ZSTD_copy8(op, match);
++ }
++ op += 8;
++ match += 8;
++
++ if (oMatchEnd > oend - (16 - MINMATCH)) {
++ if (op < oend_w) {
++ ZSTD_wildcopy(op, match, oend_w - op);
++ match += oend_w - op;
++ op = oend_w;
++ }
++ while (op < oMatchEnd)
++ *op++ = *match++;
++ } else {
++ ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */
++ }
++ return sequenceLength;
++}
++
++static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize)
++{
++ const BYTE *ip = (const BYTE *)seqStart;
++ const BYTE *const iend = ip + seqSize;
++ BYTE *const ostart = (BYTE * const)dst;
++ BYTE *const oend = ostart + maxDstSize;
++ BYTE *op = ostart;
++ const BYTE *litPtr = dctx->litPtr;
++ const BYTE *const litEnd = litPtr + dctx->litSize;
++ const BYTE *const base = (const BYTE *)(dctx->base);
++ const BYTE *const vBase = (const BYTE *)(dctx->vBase);
++ const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd);
++ unsigned const windowSize = dctx->fParams.windowSize;
++ int nbSeq;
++
++ /* Build Decoding Tables */
++ {
++ size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize);
++ if (ZSTD_isError(seqHSize))
++ return seqHSize;
++ ip += seqHSize;
++ }
++
++ /* Regen sequences */
++ if (nbSeq) {
++#define STORED_SEQS 4
++#define STOSEQ_MASK (STORED_SEQS - 1)
++#define ADVANCED_SEQS 4
++ seq_t *sequences = (seq_t *)dctx->entropy.workspace;
++ int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS);
++ seqState_t seqState;
++ int seqNb;
++ ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.workspace) >= sizeof(seq_t) * STORED_SEQS);
++ dctx->fseEntropy = 1;
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ seqState.prevOffset[i] = dctx->entropy.rep[i];
++ }
++ seqState.base = base;
++ seqState.pos = (size_t)(op - base);
++ seqState.gotoDict = (uPtrDiff)dictEnd - (uPtrDiff)base; /* cast to avoid undefined behaviour */
++ CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected);
++ FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr);
++ FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr);
++ FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr);
++
++ /* prepare in advance */
++ for (seqNb = 0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb < seqAdvance; seqNb++) {
++ sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize);
++ }
++ if (seqNb < seqAdvance)
++ return ERROR(corruption_detected);
++
++ /* decode and decompress */
++ for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb < nbSeq; seqNb++) {
++ seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize);
++ size_t const oneSeqSize =
++ ZSTD_execSequenceLong(op, oend, sequences[(seqNb - ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd);
++ if (ZSTD_isError(oneSeqSize))
++ return oneSeqSize;
++ ZSTD_PREFETCH(sequence.match);
++ sequences[seqNb & STOSEQ_MASK] = sequence;
++ op += oneSeqSize;
++ }
++ if (seqNb < nbSeq)
++ return ERROR(corruption_detected);
++
++ /* finish queue */
++ seqNb -= seqAdvance;
++ for (; seqNb < nbSeq; seqNb++) {
++ size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[seqNb & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd);
++ if (ZSTD_isError(oneSeqSize))
++ return oneSeqSize;
++ op += oneSeqSize;
++ }
++
++ /* save reps for next block */
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]);
++ }
++ }
++
++ /* last literal segment */
++ {
++ size_t const lastLLSize = litEnd - litPtr;
++ if (lastLLSize > (size_t)(oend - op))
++ return ERROR(dstSize_tooSmall);
++ memcpy(op, litPtr, lastLLSize);
++ op += lastLLSize;
++ }
++
++ return op - ostart;
++}
++
++static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{ /* blockType == blockCompressed */
++ const BYTE *ip = (const BYTE *)src;
++
++ if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX)
++ return ERROR(srcSize_wrong);
++
++ /* Decode literals section */
++ {
++ size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
++ if (ZSTD_isError(litCSize))
++ return litCSize;
++ ip += litCSize;
++ srcSize -= litCSize;
++ }
++ if (sizeof(size_t) > 4) /* do not enable prefetching on 32-bits x86, as it's performance detrimental */
++ /* likely because of register pressure */
++ /* if that's the correct cause, then 32-bits ARM should be affected differently */
++ /* it would be good to test this on ARM real hardware, to see if prefetch version improves speed */
++ if (dctx->fParams.windowSize > (1 << 23))
++ return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize);
++ return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize);
++}
++
++static void ZSTD_checkContinuity(ZSTD_DCtx *dctx, const void *dst)
++{
++ if (dst != dctx->previousDstEnd) { /* not contiguous */
++ dctx->dictEnd = dctx->previousDstEnd;
++ dctx->vBase = (const char *)dst - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base));
++ dctx->base = dst;
++ dctx->previousDstEnd = dst;
++ }
++}
++
++size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ size_t dSize;
++ ZSTD_checkContinuity(dctx, dst);
++ dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize);
++ dctx->previousDstEnd = (char *)dst + dSize;
++ return dSize;
++}
++
++/** ZSTD_insertBlock() :
++ insert `src` block into `dctx` history. Useful to track uncompressed blocks. */
++size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart, size_t blockSize)
++{
++ ZSTD_checkContinuity(dctx, blockStart);
++ dctx->previousDstEnd = (const char *)blockStart + blockSize;
++ return blockSize;
++}
++
++size_t ZSTD_generateNxBytes(void *dst, size_t dstCapacity, BYTE byte, size_t length)
++{
++ if (length > dstCapacity)
++ return ERROR(dstSize_tooSmall);
++ memset(dst, byte, length);
++ return length;
++}
++
++/** ZSTD_findFrameCompressedSize() :
++ * compatible with legacy mode
++ * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame
++ * `srcSize` must be at least as large as the frame contained
++ * @return : the compressed size of the frame starting at `src` */
++size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize)
++{
++ if (srcSize >= ZSTD_skippableHeaderSize && (ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
++ return ZSTD_skippableHeaderSize + ZSTD_readLE32((const BYTE *)src + 4);
++ } else {
++ const BYTE *ip = (const BYTE *)src;
++ const BYTE *const ipstart = ip;
++ size_t remainingSize = srcSize;
++ ZSTD_frameParams fParams;
++
++ size_t const headerSize = ZSTD_frameHeaderSize(ip, remainingSize);
++ if (ZSTD_isError(headerSize))
++ return headerSize;
++
++ /* Frame Header */
++ {
++ size_t const ret = ZSTD_getFrameParams(&fParams, ip, remainingSize);
++ if (ZSTD_isError(ret))
++ return ret;
++ if (ret > 0)
++ return ERROR(srcSize_wrong);
++ }
++
++ ip += headerSize;
++ remainingSize -= headerSize;
++
++ /* Loop on each block */
++ while (1) {
++ blockProperties_t blockProperties;
++ size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
++ if (ZSTD_isError(cBlockSize))
++ return cBlockSize;
++
++ if (ZSTD_blockHeaderSize + cBlockSize > remainingSize)
++ return ERROR(srcSize_wrong);
++
++ ip += ZSTD_blockHeaderSize + cBlockSize;
++ remainingSize -= ZSTD_blockHeaderSize + cBlockSize;
++
++ if (blockProperties.lastBlock)
++ break;
++ }
++
++ if (fParams.checksumFlag) { /* Frame content checksum */
++ if (remainingSize < 4)
++ return ERROR(srcSize_wrong);
++ ip += 4;
++ remainingSize -= 4;
++ }
++
++ return ip - ipstart;
++ }
++}
++
++/*! ZSTD_decompressFrame() :
++* @dctx must be properly initialized */
++static size_t ZSTD_decompressFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void **srcPtr, size_t *srcSizePtr)
++{
++ const BYTE *ip = (const BYTE *)(*srcPtr);
++ BYTE *const ostart = (BYTE * const)dst;
++ BYTE *const oend = ostart + dstCapacity;
++ BYTE *op = ostart;
++ size_t remainingSize = *srcSizePtr;
++
++ /* check */
++ if (remainingSize < ZSTD_frameHeaderSize_min + ZSTD_blockHeaderSize)
++ return ERROR(srcSize_wrong);
++
++ /* Frame Header */
++ {
++ size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_frameHeaderSize_prefix);
++ if (ZSTD_isError(frameHeaderSize))
++ return frameHeaderSize;
++ if (remainingSize < frameHeaderSize + ZSTD_blockHeaderSize)
++ return ERROR(srcSize_wrong);
++ CHECK_F(ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize));
++ ip += frameHeaderSize;
++ remainingSize -= frameHeaderSize;
++ }
++
++ /* Loop on each block */
++ while (1) {
++ size_t decodedSize;
++ blockProperties_t blockProperties;
++ size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
++ if (ZSTD_isError(cBlockSize))
++ return cBlockSize;
++
++ ip += ZSTD_blockHeaderSize;
++ remainingSize -= ZSTD_blockHeaderSize;
++ if (cBlockSize > remainingSize)
++ return ERROR(srcSize_wrong);
++
++ switch (blockProperties.blockType) {
++ case bt_compressed: decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend - op, ip, cBlockSize); break;
++ case bt_raw: decodedSize = ZSTD_copyRawBlock(op, oend - op, ip, cBlockSize); break;
++ case bt_rle: decodedSize = ZSTD_generateNxBytes(op, oend - op, *ip, blockProperties.origSize); break;
++ case bt_reserved:
++ default: return ERROR(corruption_detected);
++ }
++
++ if (ZSTD_isError(decodedSize))
++ return decodedSize;
++ if (dctx->fParams.checksumFlag)
++ xxh64_update(&dctx->xxhState, op, decodedSize);
++ op += decodedSize;
++ ip += cBlockSize;
++ remainingSize -= cBlockSize;
++ if (blockProperties.lastBlock)
++ break;
++ }
++
++ if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */
++ U32 const checkCalc = (U32)xxh64_digest(&dctx->xxhState);
++ U32 checkRead;
++ if (remainingSize < 4)
++ return ERROR(checksum_wrong);
++ checkRead = ZSTD_readLE32(ip);
++ if (checkRead != checkCalc)
++ return ERROR(checksum_wrong);
++ ip += 4;
++ remainingSize -= 4;
++ }
++
++ /* Allow caller to get size read */
++ *srcPtr = ip;
++ *srcSizePtr = remainingSize;
++ return op - ostart;
++}
++
++static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict);
++static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict);
++
++static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize,
++ const ZSTD_DDict *ddict)
++{
++ void *const dststart = dst;
++
++ if (ddict) {
++ if (dict) {
++ /* programmer error, these two cases should be mutually exclusive */
++ return ERROR(GENERIC);
++ }
++
++ dict = ZSTD_DDictDictContent(ddict);
++ dictSize = ZSTD_DDictDictSize(ddict);
++ }
++
++ while (srcSize >= ZSTD_frameHeaderSize_prefix) {
++ U32 magicNumber;
++
++ magicNumber = ZSTD_readLE32(src);
++ if (magicNumber != ZSTD_MAGICNUMBER) {
++ if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
++ size_t skippableSize;
++ if (srcSize < ZSTD_skippableHeaderSize)
++ return ERROR(srcSize_wrong);
++ skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize;
++ if (srcSize < skippableSize) {
++ return ERROR(srcSize_wrong);
++ }
++
++ src = (const BYTE *)src + skippableSize;
++ srcSize -= skippableSize;
++ continue;
++ } else {
++ return ERROR(prefix_unknown);
++ }
++ }
++
++ if (ddict) {
++ /* we were called from ZSTD_decompress_usingDDict */
++ ZSTD_refDDict(dctx, ddict);
++ } else {
++ /* this will initialize correctly with no dict if dict == NULL, so
++ * use this in all cases but ddict */
++ CHECK_F(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize));
++ }
++ ZSTD_checkContinuity(dctx, dst);
++
++ {
++ const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity, &src, &srcSize);
++ if (ZSTD_isError(res))
++ return res;
++ /* don't need to bounds check this, ZSTD_decompressFrame will have
++ * already */
++ dst = (BYTE *)dst + res;
++ dstCapacity -= res;
++ }
++ }
++
++ if (srcSize)
++ return ERROR(srcSize_wrong); /* input not entirely consumed */
++
++ return (BYTE *)dst - (BYTE *)dststart;
++}
++
++size_t ZSTD_decompress_usingDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize)
++{
++ return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, dict, dictSize, NULL);
++}
++
++size_t ZSTD_decompressDCtx(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ return ZSTD_decompress_usingDict(dctx, dst, dstCapacity, src, srcSize, NULL, 0);
++}
++
++/*-**************************************
++* Advanced Streaming Decompression API
++* Bufferless and synchronous
++****************************************/
++size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx) { return dctx->expected; }
++
++ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx)
++{
++ switch (dctx->stage) {
++ default: /* should not happen */
++ case ZSTDds_getFrameHeaderSize:
++ case ZSTDds_decodeFrameHeader: return ZSTDnit_frameHeader;
++ case ZSTDds_decodeBlockHeader: return ZSTDnit_blockHeader;
++ case ZSTDds_decompressBlock: return ZSTDnit_block;
++ case ZSTDds_decompressLastBlock: return ZSTDnit_lastBlock;
++ case ZSTDds_checkChecksum: return ZSTDnit_checksum;
++ case ZSTDds_decodeSkippableHeader:
++ case ZSTDds_skipFrame: return ZSTDnit_skippableFrame;
++ }
++}
++
++int ZSTD_isSkipFrame(ZSTD_DCtx *dctx) { return dctx->stage == ZSTDds_skipFrame; } /* for zbuff */
++
++/** ZSTD_decompressContinue() :
++* @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity)
++* or an error code, which can be tested using ZSTD_isError() */
++size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ /* Sanity check */
++ if (srcSize != dctx->expected)
++ return ERROR(srcSize_wrong);
++ if (dstCapacity)
++ ZSTD_checkContinuity(dctx, dst);
++
++ switch (dctx->stage) {
++ case ZSTDds_getFrameHeaderSize:
++ if (srcSize != ZSTD_frameHeaderSize_prefix)
++ return ERROR(srcSize_wrong); /* impossible */
++ if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
++ memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix);
++ dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix; /* magic number + skippable frame length */
++ dctx->stage = ZSTDds_decodeSkippableHeader;
++ return 0;
++ }
++ dctx->headerSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_prefix);
++ if (ZSTD_isError(dctx->headerSize))
++ return dctx->headerSize;
++ memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix);
++ if (dctx->headerSize > ZSTD_frameHeaderSize_prefix) {
++ dctx->expected = dctx->headerSize - ZSTD_frameHeaderSize_prefix;
++ dctx->stage = ZSTDds_decodeFrameHeader;
++ return 0;
++ }
++ dctx->expected = 0; /* not necessary to copy more */
++
++ case ZSTDds_decodeFrameHeader:
++ memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
++ CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize));
++ dctx->expected = ZSTD_blockHeaderSize;
++ dctx->stage = ZSTDds_decodeBlockHeader;
++ return 0;
++
++ case ZSTDds_decodeBlockHeader: {
++ blockProperties_t bp;
++ size_t const cBlockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp);
++ if (ZSTD_isError(cBlockSize))
++ return cBlockSize;
++ dctx->expected = cBlockSize;
++ dctx->bType = bp.blockType;
++ dctx->rleSize = bp.origSize;
++ if (cBlockSize) {
++ dctx->stage = bp.lastBlock ? ZSTDds_decompressLastBlock : ZSTDds_decompressBlock;
++ return 0;
++ }
++ /* empty block */
++ if (bp.lastBlock) {
++ if (dctx->fParams.checksumFlag) {
++ dctx->expected = 4;
++ dctx->stage = ZSTDds_checkChecksum;
++ } else {
++ dctx->expected = 0; /* end of frame */
++ dctx->stage = ZSTDds_getFrameHeaderSize;
++ }
++ } else {
++ dctx->expected = 3; /* go directly to next header */
++ dctx->stage = ZSTDds_decodeBlockHeader;
++ }
++ return 0;
++ }
++ case ZSTDds_decompressLastBlock:
++ case ZSTDds_decompressBlock: {
++ size_t rSize;
++ switch (dctx->bType) {
++ case bt_compressed: rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); break;
++ case bt_raw: rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); break;
++ case bt_rle: rSize = ZSTD_setRleBlock(dst, dstCapacity, src, srcSize, dctx->rleSize); break;
++ case bt_reserved: /* should never happen */
++ default: return ERROR(corruption_detected);
++ }
++ if (ZSTD_isError(rSize))
++ return rSize;
++ if (dctx->fParams.checksumFlag)
++ xxh64_update(&dctx->xxhState, dst, rSize);
++
++ if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */
++ if (dctx->fParams.checksumFlag) { /* another round for frame checksum */
++ dctx->expected = 4;
++ dctx->stage = ZSTDds_checkChecksum;
++ } else {
++ dctx->expected = 0; /* ends here */
++ dctx->stage = ZSTDds_getFrameHeaderSize;
++ }
++ } else {
++ dctx->stage = ZSTDds_decodeBlockHeader;
++ dctx->expected = ZSTD_blockHeaderSize;
++ dctx->previousDstEnd = (char *)dst + rSize;
++ }
++ return rSize;
++ }
++ case ZSTDds_checkChecksum: {
++ U32 const h32 = (U32)xxh64_digest(&dctx->xxhState);
++ U32 const check32 = ZSTD_readLE32(src); /* srcSize == 4, guaranteed by dctx->expected */
++ if (check32 != h32)
++ return ERROR(checksum_wrong);
++ dctx->expected = 0;
++ dctx->stage = ZSTDds_getFrameHeaderSize;
++ return 0;
++ }
++ case ZSTDds_decodeSkippableHeader: {
++ memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
++ dctx->expected = ZSTD_readLE32(dctx->headerBuffer + 4);
++ dctx->stage = ZSTDds_skipFrame;
++ return 0;
++ }
++ case ZSTDds_skipFrame: {
++ dctx->expected = 0;
++ dctx->stage = ZSTDds_getFrameHeaderSize;
++ return 0;
++ }
++ default:
++ return ERROR(GENERIC); /* impossible */
++ }
++}
++
++static size_t ZSTD_refDictContent(ZSTD_DCtx *dctx, const void *dict, size_t dictSize)
++{
++ dctx->dictEnd = dctx->previousDstEnd;
++ dctx->vBase = (const char *)dict - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base));
++ dctx->base = dict;
++ dctx->previousDstEnd = (const char *)dict + dictSize;
++ return 0;
++}
++
++/* ZSTD_loadEntropy() :
++ * dict : must point at beginning of a valid zstd dictionary
++ * @return : size of entropy tables read */
++static size_t ZSTD_loadEntropy(ZSTD_entropyTables_t *entropy, const void *const dict, size_t const dictSize)
++{
++ const BYTE *dictPtr = (const BYTE *)dict;
++ const BYTE *const dictEnd = dictPtr + dictSize;
++
++ if (dictSize <= 8)
++ return ERROR(dictionary_corrupted);
++ dictPtr += 8; /* skip header = magic + dictID */
++
++ {
++ size_t const hSize = HUF_readDTableX4_wksp(entropy->hufTable, dictPtr, dictEnd - dictPtr, entropy->workspace, sizeof(entropy->workspace));
++ if (HUF_isError(hSize))
++ return ERROR(dictionary_corrupted);
++ dictPtr += hSize;
++ }
++
++ {
++ short offcodeNCount[MaxOff + 1];
++ U32 offcodeMaxValue = MaxOff, offcodeLog;
++ size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr);
++ if (FSE_isError(offcodeHeaderSize))
++ return ERROR(dictionary_corrupted);
++ if (offcodeLog > OffFSELog)
++ return ERROR(dictionary_corrupted);
++ CHECK_E(FSE_buildDTable_wksp(entropy->OFTable, offcodeNCount, offcodeMaxValue, offcodeLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted);
++ dictPtr += offcodeHeaderSize;
++ }
++
++ {
++ short matchlengthNCount[MaxML + 1];
++ unsigned matchlengthMaxValue = MaxML, matchlengthLog;
++ size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr);
++ if (FSE_isError(matchlengthHeaderSize))
++ return ERROR(dictionary_corrupted);
++ if (matchlengthLog > MLFSELog)
++ return ERROR(dictionary_corrupted);
++ CHECK_E(FSE_buildDTable_wksp(entropy->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted);
++ dictPtr += matchlengthHeaderSize;
++ }
++
++ {
++ short litlengthNCount[MaxLL + 1];
++ unsigned litlengthMaxValue = MaxLL, litlengthLog;
++ size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr);
++ if (FSE_isError(litlengthHeaderSize))
++ return ERROR(dictionary_corrupted);
++ if (litlengthLog > LLFSELog)
++ return ERROR(dictionary_corrupted);
++ CHECK_E(FSE_buildDTable_wksp(entropy->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted);
++ dictPtr += litlengthHeaderSize;
++ }
++
++ if (dictPtr + 12 > dictEnd)
++ return ERROR(dictionary_corrupted);
++ {
++ int i;
++ size_t const dictContentSize = (size_t)(dictEnd - (dictPtr + 12));
++ for (i = 0; i < 3; i++) {
++ U32 const rep = ZSTD_readLE32(dictPtr);
++ dictPtr += 4;
++ if (rep == 0 || rep >= dictContentSize)
++ return ERROR(dictionary_corrupted);
++ entropy->rep[i] = rep;
++ }
++ }
++
++ return dictPtr - (const BYTE *)dict;
++}
++
++static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx *dctx, const void *dict, size_t dictSize)
++{
++ if (dictSize < 8)
++ return ZSTD_refDictContent(dctx, dict, dictSize);
++ {
++ U32 const magic = ZSTD_readLE32(dict);
++ if (magic != ZSTD_DICT_MAGIC) {
++ return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */
++ }
++ }
++ dctx->dictID = ZSTD_readLE32((const char *)dict + 4);
++
++ /* load entropy tables */
++ {
++ size_t const eSize = ZSTD_loadEntropy(&dctx->entropy, dict, dictSize);
++ if (ZSTD_isError(eSize))
++ return ERROR(dictionary_corrupted);
++ dict = (const char *)dict + eSize;
++ dictSize -= eSize;
++ }
++ dctx->litEntropy = dctx->fseEntropy = 1;
++
++ /* reference dictionary content */
++ return ZSTD_refDictContent(dctx, dict, dictSize);
++}
++
++size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict, size_t dictSize)
++{
++ CHECK_F(ZSTD_decompressBegin(dctx));
++ if (dict && dictSize)
++ CHECK_E(ZSTD_decompress_insertDictionary(dctx, dict, dictSize), dictionary_corrupted);
++ return 0;
++}
++
++/* ====== ZSTD_DDict ====== */
++
++struct ZSTD_DDict_s {
++ void *dictBuffer;
++ const void *dictContent;
++ size_t dictSize;
++ ZSTD_entropyTables_t entropy;
++ U32 dictID;
++ U32 entropyPresent;
++ ZSTD_customMem cMem;
++}; /* typedef'd to ZSTD_DDict within "zstd.h" */
++
++size_t ZSTD_DDictWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DDict)); }
++
++static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict) { return ddict->dictContent; }
++
++static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict) { return ddict->dictSize; }
++
++static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict)
++{
++ ZSTD_decompressBegin(dstDCtx); /* init */
++ if (ddict) { /* support refDDict on NULL */
++ dstDCtx->dictID = ddict->dictID;
++ dstDCtx->base = ddict->dictContent;
++ dstDCtx->vBase = ddict->dictContent;
++ dstDCtx->dictEnd = (const BYTE *)ddict->dictContent + ddict->dictSize;
++ dstDCtx->previousDstEnd = dstDCtx->dictEnd;
++ if (ddict->entropyPresent) {
++ dstDCtx->litEntropy = 1;
++ dstDCtx->fseEntropy = 1;
++ dstDCtx->LLTptr = ddict->entropy.LLTable;
++ dstDCtx->MLTptr = ddict->entropy.MLTable;
++ dstDCtx->OFTptr = ddict->entropy.OFTable;
++ dstDCtx->HUFptr = ddict->entropy.hufTable;
++ dstDCtx->entropy.rep[0] = ddict->entropy.rep[0];
++ dstDCtx->entropy.rep[1] = ddict->entropy.rep[1];
++ dstDCtx->entropy.rep[2] = ddict->entropy.rep[2];
++ } else {
++ dstDCtx->litEntropy = 0;
++ dstDCtx->fseEntropy = 0;
++ }
++ }
++}
++
++static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict *ddict)
++{
++ ddict->dictID = 0;
++ ddict->entropyPresent = 0;
++ if (ddict->dictSize < 8)
++ return 0;
++ {
++ U32 const magic = ZSTD_readLE32(ddict->dictContent);
++ if (magic != ZSTD_DICT_MAGIC)
++ return 0; /* pure content mode */
++ }
++ ddict->dictID = ZSTD_readLE32((const char *)ddict->dictContent + 4);
++
++ /* load entropy tables */
++ CHECK_E(ZSTD_loadEntropy(&ddict->entropy, ddict->dictContent, ddict->dictSize), dictionary_corrupted);
++ ddict->entropyPresent = 1;
++ return 0;
++}
++
++static ZSTD_DDict *ZSTD_createDDict_advanced(const void *dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem)
++{
++ if (!customMem.customAlloc || !customMem.customFree)
++ return NULL;
++
++ {
++ ZSTD_DDict *const ddict = (ZSTD_DDict *)ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
++ if (!ddict)
++ return NULL;
++ ddict->cMem = customMem;
++
++ if ((byReference) || (!dict) || (!dictSize)) {
++ ddict->dictBuffer = NULL;
++ ddict->dictContent = dict;
++ } else {
++ void *const internalBuffer = ZSTD_malloc(dictSize, customMem);
++ if (!internalBuffer) {
++ ZSTD_freeDDict(ddict);
++ return NULL;
++ }
++ memcpy(internalBuffer, dict, dictSize);
++ ddict->dictBuffer = internalBuffer;
++ ddict->dictContent = internalBuffer;
++ }
++ ddict->dictSize = dictSize;
++ ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */
++ /* parse dictionary content */
++ {
++ size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict);
++ if (ZSTD_isError(errorCode)) {
++ ZSTD_freeDDict(ddict);
++ return NULL;
++ }
++ }
++
++ return ddict;
++ }
++}
++
++/*! ZSTD_initDDict() :
++* Create a digested dictionary, to start decompression without startup delay.
++* `dict` content is copied inside DDict.
++* Consequently, `dict` can be released after `ZSTD_DDict` creation */
++ZSTD_DDict *ZSTD_initDDict(const void *dict, size_t dictSize, void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
++ return ZSTD_createDDict_advanced(dict, dictSize, 1, stackMem);
++}
++
++size_t ZSTD_freeDDict(ZSTD_DDict *ddict)
++{
++ if (ddict == NULL)
++ return 0; /* support free on NULL */
++ {
++ ZSTD_customMem const cMem = ddict->cMem;
++ ZSTD_free(ddict->dictBuffer, cMem);
++ ZSTD_free(ddict, cMem);
++ return 0;
++ }
++}
++
++/*! ZSTD_getDictID_fromDict() :
++ * Provides the dictID stored within dictionary.
++ * if @return == 0, the dictionary is not conformant with Zstandard specification.
++ * It can still be loaded, but as a content-only dictionary. */
++unsigned ZSTD_getDictID_fromDict(const void *dict, size_t dictSize)
++{
++ if (dictSize < 8)
++ return 0;
++ if (ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC)
++ return 0;
++ return ZSTD_readLE32((const char *)dict + 4);
++}
++
++/*! ZSTD_getDictID_fromDDict() :
++ * Provides the dictID of the dictionary loaded into `ddict`.
++ * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
++ * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */
++unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict)
++{
++ if (ddict == NULL)
++ return 0;
++ return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize);
++}
++
++/*! ZSTD_getDictID_fromFrame() :
++ * Provides the dictID required to decompressed the frame stored within `src`.
++ * If @return == 0, the dictID could not be decoded.
++ * This could for one of the following reasons :
++ * - The frame does not require a dictionary to be decoded (most common case).
++ * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information.
++ * Note : this use case also happens when using a non-conformant dictionary.
++ * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`).
++ * - This is not a Zstandard frame.
++ * When identifying the exact failure cause, it's possible to used ZSTD_getFrameParams(), which will provide a more precise error code. */
++unsigned ZSTD_getDictID_fromFrame(const void *src, size_t srcSize)
++{
++ ZSTD_frameParams zfp = {0, 0, 0, 0};
++ size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize);
++ if (ZSTD_isError(hError))
++ return 0;
++ return zfp.dictID;
++}
++
++/*! ZSTD_decompress_usingDDict() :
++* Decompression using a pre-digested Dictionary
++* Use dictionary without significant overhead. */
++size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_DDict *ddict)
++{
++ /* pass content and size in case legacy frames are encountered */
++ return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, NULL, 0, ddict);
++}
++
++/*=====================================
++* Streaming decompression
++*====================================*/
++
++typedef enum { zdss_init, zdss_loadHeader, zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
++
++/* *** Resource management *** */
++struct ZSTD_DStream_s {
++ ZSTD_DCtx *dctx;
++ ZSTD_DDict *ddictLocal;
++ const ZSTD_DDict *ddict;
++ ZSTD_frameParams fParams;
++ ZSTD_dStreamStage stage;
++ char *inBuff;
++ size_t inBuffSize;
++ size_t inPos;
++ size_t maxWindowSize;
++ char *outBuff;
++ size_t outBuffSize;
++ size_t outStart;
++ size_t outEnd;
++ size_t blockSize;
++ BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; /* tmp buffer to store frame header */
++ size_t lhSize;
++ ZSTD_customMem customMem;
++ void *legacyContext;
++ U32 previousLegacyVersion;
++ U32 legacyVersion;
++ U32 hostageByte;
++}; /* typedef'd to ZSTD_DStream within "zstd.h" */
++
++size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize)
++{
++ size_t const blockSize = MIN(maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
++ size_t const inBuffSize = blockSize;
++ size_t const outBuffSize = maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
++ return ZSTD_DCtxWorkspaceBound() + ZSTD_ALIGN(sizeof(ZSTD_DStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize);
++}
++
++static ZSTD_DStream *ZSTD_createDStream_advanced(ZSTD_customMem customMem)
++{
++ ZSTD_DStream *zds;
++
++ if (!customMem.customAlloc || !customMem.customFree)
++ return NULL;
++
++ zds = (ZSTD_DStream *)ZSTD_malloc(sizeof(ZSTD_DStream), customMem);
++ if (zds == NULL)
++ return NULL;
++ memset(zds, 0, sizeof(ZSTD_DStream));
++ memcpy(&zds->customMem, &customMem, sizeof(ZSTD_customMem));
++ zds->dctx = ZSTD_createDCtx_advanced(customMem);
++ if (zds->dctx == NULL) {
++ ZSTD_freeDStream(zds);
++ return NULL;
++ }
++ zds->stage = zdss_init;
++ zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
++ return zds;
++}
++
++ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize);
++ ZSTD_DStream *zds = ZSTD_createDStream_advanced(stackMem);
++ if (!zds) {
++ return NULL;
++ }
++
++ zds->maxWindowSize = maxWindowSize;
++ zds->stage = zdss_loadHeader;
++ zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
++ ZSTD_freeDDict(zds->ddictLocal);
++ zds->ddictLocal = NULL;
++ zds->ddict = zds->ddictLocal;
++ zds->legacyVersion = 0;
++ zds->hostageByte = 0;
++
++ {
++ size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
++ size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
++
++ zds->inBuff = (char *)ZSTD_malloc(blockSize, zds->customMem);
++ zds->inBuffSize = blockSize;
++ zds->outBuff = (char *)ZSTD_malloc(neededOutSize, zds->customMem);
++ zds->outBuffSize = neededOutSize;
++ if (zds->inBuff == NULL || zds->outBuff == NULL) {
++ ZSTD_freeDStream(zds);
++ return NULL;
++ }
++ }
++ return zds;
++}
++
++ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize, const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize)
++{
++ ZSTD_DStream *zds = ZSTD_initDStream(maxWindowSize, workspace, workspaceSize);
++ if (zds) {
++ zds->ddict = ddict;
++ }
++ return zds;
++}
++
++size_t ZSTD_freeDStream(ZSTD_DStream *zds)
++{
++ if (zds == NULL)
++ return 0; /* support free on null */
++ {
++ ZSTD_customMem const cMem = zds->customMem;
++ ZSTD_freeDCtx(zds->dctx);
++ zds->dctx = NULL;
++ ZSTD_freeDDict(zds->ddictLocal);
++ zds->ddictLocal = NULL;
++ ZSTD_free(zds->inBuff, cMem);
++ zds->inBuff = NULL;
++ ZSTD_free(zds->outBuff, cMem);
++ zds->outBuff = NULL;
++ ZSTD_free(zds, cMem);
++ return 0;
++ }
++}
++
++/* *** Initialization *** */
++
++size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize; }
++size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
++
++size_t ZSTD_resetDStream(ZSTD_DStream *zds)
++{
++ zds->stage = zdss_loadHeader;
++ zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
++ zds->legacyVersion = 0;
++ zds->hostageByte = 0;
++ return ZSTD_frameHeaderSize_prefix;
++}
++
++/* ***** Decompression ***** */
++
++ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize)
++{
++ size_t const length = MIN(dstCapacity, srcSize);
++ memcpy(dst, src, length);
++ return length;
++}
++
++size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inBuffer *input)
++{
++ const char *const istart = (const char *)(input->src) + input->pos;
++ const char *const iend = (const char *)(input->src) + input->size;
++ const char *ip = istart;
++ char *const ostart = (char *)(output->dst) + output->pos;
++ char *const oend = (char *)(output->dst) + output->size;
++ char *op = ostart;
++ U32 someMoreWork = 1;
++
++ while (someMoreWork) {
++ switch (zds->stage) {
++ case zdss_init:
++ ZSTD_resetDStream(zds); /* transparent reset on starting decoding a new frame */
++ /* fall-through */
++
++ case zdss_loadHeader: {
++ size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
++ if (ZSTD_isError(hSize))
++ return hSize;
++ if (hSize != 0) { /* need more input */
++ size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */
++ if (toLoad > (size_t)(iend - ip)) { /* not enough input to load full header */
++ memcpy(zds->headerBuffer + zds->lhSize, ip, iend - ip);
++ zds->lhSize += iend - ip;
++ input->pos = input->size;
++ return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) +
++ ZSTD_blockHeaderSize; /* remaining header bytes + next block header */
++ }
++ memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad);
++ zds->lhSize = hSize;
++ ip += toLoad;
++ break;
++ }
++
++ /* check for single-pass mode opportunity */
++ if (zds->fParams.frameContentSize && zds->fParams.windowSize /* skippable frame if == 0 */
++ && (U64)(size_t)(oend - op) >= zds->fParams.frameContentSize) {
++ size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend - istart);
++ if (cSize <= (size_t)(iend - istart)) {
++ size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend - op, istart, cSize, zds->ddict);
++ if (ZSTD_isError(decompressedSize))
++ return decompressedSize;
++ ip = istart + cSize;
++ op += decompressedSize;
++ zds->dctx->expected = 0;
++ zds->stage = zdss_init;
++ someMoreWork = 0;
++ break;
++ }
++ }
++
++ /* Consume header */
++ ZSTD_refDDict(zds->dctx, zds->ddict);
++ {
++ size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); /* == ZSTD_frameHeaderSize_prefix */
++ CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size));
++ {
++ size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx);
++ CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer + h1Size, h2Size));
++ }
++ }
++
++ zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
++ if (zds->fParams.windowSize > zds->maxWindowSize)
++ return ERROR(frameParameter_windowTooLarge);
++
++ /* Buffers are preallocated, but double check */
++ {
++ size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
++ size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
++ if (zds->inBuffSize < blockSize) {
++ return ERROR(GENERIC);
++ }
++ if (zds->outBuffSize < neededOutSize) {
++ return ERROR(GENERIC);
++ }
++ zds->blockSize = blockSize;
++ }
++ zds->stage = zdss_read;
++ }
++ /* pass-through */
++
++ case zdss_read: {
++ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
++ if (neededInSize == 0) { /* end of frame */
++ zds->stage = zdss_init;
++ someMoreWork = 0;
++ break;
++ }
++ if ((size_t)(iend - ip) >= neededInSize) { /* decode directly from src */
++ const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
++ size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart,
++ (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart), ip, neededInSize);
++ if (ZSTD_isError(decodedSize))
++ return decodedSize;
++ ip += neededInSize;
++ if (!decodedSize && !isSkipFrame)
++ break; /* this was just a header */
++ zds->outEnd = zds->outStart + decodedSize;
++ zds->stage = zdss_flush;
++ break;
++ }
++ if (ip == iend) {
++ someMoreWork = 0;
++ break;
++ } /* no more input */
++ zds->stage = zdss_load;
++ /* pass-through */
++ }
++
++ case zdss_load: {
++ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
++ size_t const toLoad = neededInSize - zds->inPos; /* should always be <= remaining space within inBuff */
++ size_t loadedSize;
++ if (toLoad > zds->inBuffSize - zds->inPos)
++ return ERROR(corruption_detected); /* should never happen */
++ loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend - ip);
++ ip += loadedSize;
++ zds->inPos += loadedSize;
++ if (loadedSize < toLoad) {
++ someMoreWork = 0;
++ break;
++ } /* not enough input, wait for more */
++
++ /* decode loaded input */
++ {
++ const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
++ size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart,
++ zds->inBuff, neededInSize);
++ if (ZSTD_isError(decodedSize))
++ return decodedSize;
++ zds->inPos = 0; /* input is consumed */
++ if (!decodedSize && !isSkipFrame) {
++ zds->stage = zdss_read;
++ break;
++ } /* this was just a header */
++ zds->outEnd = zds->outStart + decodedSize;
++ zds->stage = zdss_flush;
++ /* pass-through */
++ }
++ }
++
++ case zdss_flush: {
++ size_t const toFlushSize = zds->outEnd - zds->outStart;
++ size_t const flushedSize = ZSTD_limitCopy(op, oend - op, zds->outBuff + zds->outStart, toFlushSize);
++ op += flushedSize;
++ zds->outStart += flushedSize;
++ if (flushedSize == toFlushSize) { /* flush completed */
++ zds->stage = zdss_read;
++ if (zds->outStart + zds->blockSize > zds->outBuffSize)
++ zds->outStart = zds->outEnd = 0;
++ break;
++ }
++ /* cannot complete flush */
++ someMoreWork = 0;
++ break;
++ }
++ default:
++ return ERROR(GENERIC); /* impossible */
++ }
++ }
++
++ /* result */
++ input->pos += (size_t)(ip - istart);
++ output->pos += (size_t)(op - ostart);
++ {
++ size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx);
++ if (!nextSrcSizeHint) { /* frame fully decoded */
++ if (zds->outEnd == zds->outStart) { /* output fully flushed */
++ if (zds->hostageByte) {
++ if (input->pos >= input->size) {
++ zds->stage = zdss_read;
++ return 1;
++ } /* can't release hostage (not present) */
++ input->pos++; /* release hostage */
++ }
++ return 0;
++ }
++ if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */
++ input->pos--; /* note : pos > 0, otherwise, impossible to finish reading last block */
++ zds->hostageByte = 1;
++ }
++ return 1;
++ }
++ nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block); /* preload header of next block */
++ if (zds->inPos > nextSrcSizeHint)
++ return ERROR(GENERIC); /* should never happen */
++ nextSrcSizeHint -= zds->inPos; /* already loaded*/
++ return nextSrcSizeHint;
++ }
++}
++
++EXPORT_SYMBOL(ZSTD_DCtxWorkspaceBound);
++EXPORT_SYMBOL(ZSTD_initDCtx);
++EXPORT_SYMBOL(ZSTD_decompressDCtx);
++EXPORT_SYMBOL(ZSTD_decompress_usingDict);
++
++EXPORT_SYMBOL(ZSTD_DDictWorkspaceBound);
++EXPORT_SYMBOL(ZSTD_initDDict);
++EXPORT_SYMBOL(ZSTD_decompress_usingDDict);
++
++EXPORT_SYMBOL(ZSTD_DStreamWorkspaceBound);
++EXPORT_SYMBOL(ZSTD_initDStream);
++EXPORT_SYMBOL(ZSTD_initDStream_usingDDict);
++EXPORT_SYMBOL(ZSTD_resetDStream);
++EXPORT_SYMBOL(ZSTD_decompressStream);
++EXPORT_SYMBOL(ZSTD_DStreamInSize);
++EXPORT_SYMBOL(ZSTD_DStreamOutSize);
++
++EXPORT_SYMBOL(ZSTD_findFrameCompressedSize);
++EXPORT_SYMBOL(ZSTD_getFrameContentSize);
++EXPORT_SYMBOL(ZSTD_findDecompressedSize);
++
++EXPORT_SYMBOL(ZSTD_isFrame);
++EXPORT_SYMBOL(ZSTD_getDictID_fromDict);
++EXPORT_SYMBOL(ZSTD_getDictID_fromDDict);
++EXPORT_SYMBOL(ZSTD_getDictID_fromFrame);
++
++EXPORT_SYMBOL(ZSTD_getFrameParams);
++EXPORT_SYMBOL(ZSTD_decompressBegin);
++EXPORT_SYMBOL(ZSTD_decompressBegin_usingDict);
++EXPORT_SYMBOL(ZSTD_copyDCtx);
++EXPORT_SYMBOL(ZSTD_nextSrcSizeToDecompress);
++EXPORT_SYMBOL(ZSTD_decompressContinue);
++EXPORT_SYMBOL(ZSTD_nextInputType);
++
++EXPORT_SYMBOL(ZSTD_decompressBlock);
++EXPORT_SYMBOL(ZSTD_insertBlock);
++
++MODULE_LICENSE("Dual BSD/GPL");
++MODULE_DESCRIPTION("Zstd Decompressor");
+diff --git a/lib/zstd/entropy_common.c b/lib/zstd/entropy_common.c
+new file mode 100644
+index 0000000..2b0a643
+--- /dev/null
++++ b/lib/zstd/entropy_common.c
+@@ -0,0 +1,243 @@
++/*
++ * Common functions of New Generation Entropy library
++ * Copyright (C) 2016, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++
++/* *************************************
++* Dependencies
++***************************************/
++#include "error_private.h" /* ERR_*, ERROR */
++#include "fse.h"
++#include "huf.h"
++#include "mem.h"
++
++/*=== Version ===*/
++unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; }
++
++/*=== Error Management ===*/
++unsigned FSE_isError(size_t code) { return ERR_isError(code); }
++
++unsigned HUF_isError(size_t code) { return ERR_isError(code); }
++
++/*-**************************************************************
++* FSE NCount encoding-decoding
++****************************************************************/
++size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSVPtr, unsigned *tableLogPtr, const void *headerBuffer, size_t hbSize)
++{
++ const BYTE *const istart = (const BYTE *)headerBuffer;
++ const BYTE *const iend = istart + hbSize;
++ const BYTE *ip = istart;
++ int nbBits;
++ int remaining;
++ int threshold;
++ U32 bitStream;
++ int bitCount;
++ unsigned charnum = 0;
++ int previous0 = 0;
++
++ if (hbSize < 4)
++ return ERROR(srcSize_wrong);
++ bitStream = ZSTD_readLE32(ip);
++ nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */
++ if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX)
++ return ERROR(tableLog_tooLarge);
++ bitStream >>= 4;
++ bitCount = 4;
++ *tableLogPtr = nbBits;
++ remaining = (1 << nbBits) + 1;
++ threshold = 1 << nbBits;
++ nbBits++;
++
++ while ((remaining > 1) & (charnum <= *maxSVPtr)) {
++ if (previous0) {
++ unsigned n0 = charnum;
++ while ((bitStream & 0xFFFF) == 0xFFFF) {
++ n0 += 24;
++ if (ip < iend - 5) {
++ ip += 2;
++ bitStream = ZSTD_readLE32(ip) >> bitCount;
++ } else {
++ bitStream >>= 16;
++ bitCount += 16;
++ }
++ }
++ while ((bitStream & 3) == 3) {
++ n0 += 3;
++ bitStream >>= 2;
++ bitCount += 2;
++ }
++ n0 += bitStream & 3;
++ bitCount += 2;
++ if (n0 > *maxSVPtr)
++ return ERROR(maxSymbolValue_tooSmall);
++ while (charnum < n0)
++ normalizedCounter[charnum++] = 0;
++ if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) {
++ ip += bitCount >> 3;
++ bitCount &= 7;
++ bitStream = ZSTD_readLE32(ip) >> bitCount;
++ } else {
++ bitStream >>= 2;
++ }
++ }
++ {
++ int const max = (2 * threshold - 1) - remaining;
++ int count;
++
++ if ((bitStream & (threshold - 1)) < (U32)max) {
++ count = bitStream & (threshold - 1);
++ bitCount += nbBits - 1;
++ } else {
++ count = bitStream & (2 * threshold - 1);
++ if (count >= threshold)
++ count -= max;
++ bitCount += nbBits;
++ }
++
++ count--; /* extra accuracy */
++ remaining -= count < 0 ? -count : count; /* -1 means +1 */
++ normalizedCounter[charnum++] = (short)count;
++ previous0 = !count;
++ while (remaining < threshold) {
++ nbBits--;
++ threshold >>= 1;
++ }
++
++ if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) {
++ ip += bitCount >> 3;
++ bitCount &= 7;
++ } else {
++ bitCount -= (int)(8 * (iend - 4 - ip));
++ ip = iend - 4;
++ }
++ bitStream = ZSTD_readLE32(ip) >> (bitCount & 31);
++ }
++ } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */
++ if (remaining != 1)
++ return ERROR(corruption_detected);
++ if (bitCount > 32)
++ return ERROR(corruption_detected);
++ *maxSVPtr = charnum - 1;
++
++ ip += (bitCount + 7) >> 3;
++ return ip - istart;
++}
++
++/*! HUF_readStats() :
++ Read compact Huffman tree, saved by HUF_writeCTable().
++ `huffWeight` is destination buffer.
++ `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32.
++ @return : size read from `src` , or an error Code .
++ Note : Needed by HUF_readCTable() and HUF_readDTableX?() .
++*/
++size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
++{
++ U32 weightTotal;
++ const BYTE *ip = (const BYTE *)src;
++ size_t iSize;
++ size_t oSize;
++
++ if (!srcSize)
++ return ERROR(srcSize_wrong);
++ iSize = ip[0];
++ /* memset(huffWeight, 0, hwSize); */ /* is not necessary, even though some analyzer complain ... */
++
++ if (iSize >= 128) { /* special header */
++ oSize = iSize - 127;
++ iSize = ((oSize + 1) / 2);
++ if (iSize + 1 > srcSize)
++ return ERROR(srcSize_wrong);
++ if (oSize >= hwSize)
++ return ERROR(corruption_detected);
++ ip += 1;
++ {
++ U32 n;
++ for (n = 0; n < oSize; n += 2) {
++ huffWeight[n] = ip[n / 2] >> 4;
++ huffWeight[n + 1] = ip[n / 2] & 15;
++ }
++ }
++ } else { /* header compressed with FSE (normal case) */
++ if (iSize + 1 > srcSize)
++ return ERROR(srcSize_wrong);
++ oSize = FSE_decompress_wksp(huffWeight, hwSize - 1, ip + 1, iSize, 6, workspace, workspaceSize); /* max (hwSize-1) values decoded, as last one is implied */
++ if (FSE_isError(oSize))
++ return oSize;
++ }
++
++ /* collect weight stats */
++ memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32));
++ weightTotal = 0;
++ {
++ U32 n;
++ for (n = 0; n < oSize; n++) {
++ if (huffWeight[n] >= HUF_TABLELOG_MAX)
++ return ERROR(corruption_detected);
++ rankStats[huffWeight[n]]++;
++ weightTotal += (1 << huffWeight[n]) >> 1;
++ }
++ }
++ if (weightTotal == 0)
++ return ERROR(corruption_detected);
++
++ /* get last non-null symbol weight (implied, total must be 2^n) */
++ {
++ U32 const tableLog = BIT_highbit32(weightTotal) + 1;
++ if (tableLog > HUF_TABLELOG_MAX)
++ return ERROR(corruption_detected);
++ *tableLogPtr = tableLog;
++ /* determine last weight */
++ {
++ U32 const total = 1 << tableLog;
++ U32 const rest = total - weightTotal;
++ U32 const verif = 1 << BIT_highbit32(rest);
++ U32 const lastWeight = BIT_highbit32(rest) + 1;
++ if (verif != rest)
++ return ERROR(corruption_detected); /* last value must be a clean power of 2 */
++ huffWeight[oSize] = (BYTE)lastWeight;
++ rankStats[lastWeight]++;
++ }
++ }
++
++ /* check tree construction validity */
++ if ((rankStats[1] < 2) || (rankStats[1] & 1))
++ return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */
++
++ /* results */
++ *nbSymbolsPtr = (U32)(oSize + 1);
++ return iSize + 1;
++}
+diff --git a/lib/zstd/error_private.h b/lib/zstd/error_private.h
+new file mode 100644
+index 0000000..2062ff0
+--- /dev/null
++++ b/lib/zstd/error_private.h
+@@ -0,0 +1,51 @@
++/**
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++/* Note : this module is expected to remain private, do not expose it */
++
++#ifndef ERROR_H_MODULE
++#define ERROR_H_MODULE
++
++/* ****************************************
++* Dependencies
++******************************************/
++#include <linux/types.h> /* size_t */
++#include <linux/zstd.h> /* enum list */
++
++/* ****************************************
++* Compiler-specific
++******************************************/
++#define ERR_STATIC static __attribute__((unused))
++
++/*-****************************************
++* Customization (error_public.h)
++******************************************/
++typedef ZSTD_ErrorCode ERR_enum;
++#define PREFIX(name) ZSTD_error_##name
++
++/*-****************************************
++* Error codes handling
++******************************************/
++#define ERROR(name) ((size_t)-PREFIX(name))
++
++ERR_STATIC unsigned ERR_isError(size_t code) { return (code > ERROR(maxCode)); }
++
++ERR_STATIC ERR_enum ERR_getErrorCode(size_t code)
++{
++ if (!ERR_isError(code))
++ return (ERR_enum)0;
++ return (ERR_enum)(0 - code);
++}
++
++#endif /* ERROR_H_MODULE */
+diff --git a/lib/zstd/fse.h b/lib/zstd/fse.h
+new file mode 100644
+index 0000000..7460ab0
+--- /dev/null
++++ b/lib/zstd/fse.h
+@@ -0,0 +1,575 @@
++/*
++ * FSE : Finite State Entropy codec
++ * Public Prototypes declaration
++ * Copyright (C) 2013-2016, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++#ifndef FSE_H
++#define FSE_H
++
++/*-*****************************************
++* Dependencies
++******************************************/
++#include <linux/types.h> /* size_t, ptrdiff_t */
++
++/*-*****************************************
++* FSE_PUBLIC_API : control library symbols visibility
++******************************************/
++#define FSE_PUBLIC_API
++
++/*------ Version ------*/
++#define FSE_VERSION_MAJOR 0
++#define FSE_VERSION_MINOR 9
++#define FSE_VERSION_RELEASE 0
++
++#define FSE_LIB_VERSION FSE_VERSION_MAJOR.FSE_VERSION_MINOR.FSE_VERSION_RELEASE
++#define FSE_QUOTE(str) #str
++#define FSE_EXPAND_AND_QUOTE(str) FSE_QUOTE(str)
++#define FSE_VERSION_STRING FSE_EXPAND_AND_QUOTE(FSE_LIB_VERSION)
++
++#define FSE_VERSION_NUMBER (FSE_VERSION_MAJOR * 100 * 100 + FSE_VERSION_MINOR * 100 + FSE_VERSION_RELEASE)
++FSE_PUBLIC_API unsigned FSE_versionNumber(void); /**< library version number; to be used when checking dll version */
++
++/*-*****************************************
++* Tool functions
++******************************************/
++FSE_PUBLIC_API size_t FSE_compressBound(size_t size); /* maximum compressed size */
++
++/* Error Management */
++FSE_PUBLIC_API unsigned FSE_isError(size_t code); /* tells if a return value is an error code */
++
++/*-*****************************************
++* FSE detailed API
++******************************************/
++/*!
++FSE_compress() does the following:
++1. count symbol occurrence from source[] into table count[]
++2. normalize counters so that sum(count[]) == Power_of_2 (2^tableLog)
++3. save normalized counters to memory buffer using writeNCount()
++4. build encoding table 'CTable' from normalized counters
++5. encode the data stream using encoding table 'CTable'
++
++FSE_decompress() does the following:
++1. read normalized counters with readNCount()
++2. build decoding table 'DTable' from normalized counters
++3. decode the data stream using decoding table 'DTable'
++
++The following API allows targeting specific sub-functions for advanced tasks.
++For example, it's possible to compress several blocks using the same 'CTable',
++or to save and provide normalized distribution using external method.
++*/
++
++/* *** COMPRESSION *** */
++/*! FSE_optimalTableLog():
++ dynamically downsize 'tableLog' when conditions are met.
++ It saves CPU time, by using smaller tables, while preserving or even improving compression ratio.
++ @return : recommended tableLog (necessarily <= 'maxTableLog') */
++FSE_PUBLIC_API unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue);
++
++/*! FSE_normalizeCount():
++ normalize counts so that sum(count[]) == Power_of_2 (2^tableLog)
++ 'normalizedCounter' is a table of short, of minimum size (maxSymbolValue+1).
++ @return : tableLog,
++ or an errorCode, which can be tested using FSE_isError() */
++FSE_PUBLIC_API size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t srcSize, unsigned maxSymbolValue);
++
++/*! FSE_NCountWriteBound():
++ Provides the maximum possible size of an FSE normalized table, given 'maxSymbolValue' and 'tableLog'.
++ Typically useful for allocation purpose. */
++FSE_PUBLIC_API size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog);
++
++/*! FSE_writeNCount():
++ Compactly save 'normalizedCounter' into 'buffer'.
++ @return : size of the compressed table,
++ or an errorCode, which can be tested using FSE_isError(). */
++FSE_PUBLIC_API size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog);
++
++/*! Constructor and Destructor of FSE_CTable.
++ Note that FSE_CTable size depends on 'tableLog' and 'maxSymbolValue' */
++typedef unsigned FSE_CTable; /* don't allocate that. It's only meant to be more restrictive than void* */
++
++/*! FSE_compress_usingCTable():
++ Compress `src` using `ct` into `dst` which must be already allocated.
++ @return : size of compressed data (<= `dstCapacity`),
++ or 0 if compressed data could not fit into `dst`,
++ or an errorCode, which can be tested using FSE_isError() */
++FSE_PUBLIC_API size_t FSE_compress_usingCTable(void *dst, size_t dstCapacity, const void *src, size_t srcSize, const FSE_CTable *ct);
++
++/*!
++Tutorial :
++----------
++The first step is to count all symbols. FSE_count() does this job very fast.
++Result will be saved into 'count', a table of unsigned int, which must be already allocated, and have 'maxSymbolValuePtr[0]+1' cells.
++'src' is a table of bytes of size 'srcSize'. All values within 'src' MUST be <= maxSymbolValuePtr[0]
++maxSymbolValuePtr[0] will be updated, with its real value (necessarily <= original value)
++FSE_count() will return the number of occurrence of the most frequent symbol.
++This can be used to know if there is a single symbol within 'src', and to quickly evaluate its compressibility.
++If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()).
++
++The next step is to normalize the frequencies.
++FSE_normalizeCount() will ensure that sum of frequencies is == 2 ^'tableLog'.
++It also guarantees a minimum of 1 to any Symbol with frequency >= 1.
++You can use 'tableLog'==0 to mean "use default tableLog value".
++If you are unsure of which tableLog value to use, you can ask FSE_optimalTableLog(),
++which will provide the optimal valid tableLog given sourceSize, maxSymbolValue, and a user-defined maximum (0 means "default").
++
++The result of FSE_normalizeCount() will be saved into a table,
++called 'normalizedCounter', which is a table of signed short.
++'normalizedCounter' must be already allocated, and have at least 'maxSymbolValue+1' cells.
++The return value is tableLog if everything proceeded as expected.
++It is 0 if there is a single symbol within distribution.
++If there is an error (ex: invalid tableLog value), the function will return an ErrorCode (which can be tested using FSE_isError()).
++
++'normalizedCounter' can be saved in a compact manner to a memory area using FSE_writeNCount().
++'buffer' must be already allocated.
++For guaranteed success, buffer size must be at least FSE_headerBound().
++The result of the function is the number of bytes written into 'buffer'.
++If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError(); ex : buffer size too small).
++
++'normalizedCounter' can then be used to create the compression table 'CTable'.
++The space required by 'CTable' must be already allocated, using FSE_createCTable().
++You can then use FSE_buildCTable() to fill 'CTable'.
++If there is an error, both functions will return an ErrorCode (which can be tested using FSE_isError()).
++
++'CTable' can then be used to compress 'src', with FSE_compress_usingCTable().
++Similar to FSE_count(), the convention is that 'src' is assumed to be a table of char of size 'srcSize'
++The function returns the size of compressed data (without header), necessarily <= `dstCapacity`.
++If it returns '0', compressed data could not fit into 'dst'.
++If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()).
++*/
++
++/* *** DECOMPRESSION *** */
++
++/*! FSE_readNCount():
++ Read compactly saved 'normalizedCounter' from 'rBuffer'.
++ @return : size read from 'rBuffer',
++ or an errorCode, which can be tested using FSE_isError().
++ maxSymbolValuePtr[0] and tableLogPtr[0] will also be updated with their respective values */
++FSE_PUBLIC_API size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSymbolValuePtr, unsigned *tableLogPtr, const void *rBuffer, size_t rBuffSize);
++
++/*! Constructor and Destructor of FSE_DTable.
++ Note that its size depends on 'tableLog' */
++typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */
++
++/*! FSE_buildDTable():
++ Builds 'dt', which must be already allocated, using FSE_createDTable().
++ return : 0, or an errorCode, which can be tested using FSE_isError() */
++FSE_PUBLIC_API size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize);
++
++/*! FSE_decompress_usingDTable():
++ Decompress compressed source `cSrc` of size `cSrcSize` using `dt`
++ into `dst` which must be already allocated.
++ @return : size of regenerated data (necessarily <= `dstCapacity`),
++ or an errorCode, which can be tested using FSE_isError() */
++FSE_PUBLIC_API size_t FSE_decompress_usingDTable(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt);
++
++/*!
++Tutorial :
++----------
++(Note : these functions only decompress FSE-compressed blocks.
++ If block is uncompressed, use memcpy() instead
++ If block is a single repeated byte, use memset() instead )
++
++The first step is to obtain the normalized frequencies of symbols.
++This can be performed by FSE_readNCount() if it was saved using FSE_writeNCount().
++'normalizedCounter' must be already allocated, and have at least 'maxSymbolValuePtr[0]+1' cells of signed short.
++In practice, that means it's necessary to know 'maxSymbolValue' beforehand,
++or size the table to handle worst case situations (typically 256).
++FSE_readNCount() will provide 'tableLog' and 'maxSymbolValue'.
++The result of FSE_readNCount() is the number of bytes read from 'rBuffer'.
++Note that 'rBufferSize' must be at least 4 bytes, even if useful information is less than that.
++If there is an error, the function will return an error code, which can be tested using FSE_isError().
++
++The next step is to build the decompression tables 'FSE_DTable' from 'normalizedCounter'.
++This is performed by the function FSE_buildDTable().
++The space required by 'FSE_DTable' must be already allocated using FSE_createDTable().
++If there is an error, the function will return an error code, which can be tested using FSE_isError().
++
++`FSE_DTable` can then be used to decompress `cSrc`, with FSE_decompress_usingDTable().
++`cSrcSize` must be strictly correct, otherwise decompression will fail.
++FSE_decompress_usingDTable() result will tell how many bytes were regenerated (<=`dstCapacity`).
++If there is an error, the function will return an error code, which can be tested using FSE_isError(). (ex: dst buffer too small)
++*/
++
++/* *** Dependency *** */
++#include "bitstream.h"
++
++/* *****************************************
++* Static allocation
++*******************************************/
++/* FSE buffer bounds */
++#define FSE_NCOUNTBOUND 512
++#define FSE_BLOCKBOUND(size) (size + (size >> 7))
++#define FSE_COMPRESSBOUND(size) (FSE_NCOUNTBOUND + FSE_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
++
++/* It is possible to statically allocate FSE CTable/DTable as a table of FSE_CTable/FSE_DTable using below macros */
++#define FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) (1 + (1 << (maxTableLog - 1)) + ((maxSymbolValue + 1) * 2))
++#define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1 << maxTableLog))
++
++/* *****************************************
++* FSE advanced API
++*******************************************/
++/* FSE_count_wksp() :
++ * Same as FSE_count(), but using an externally provided scratch buffer.
++ * `workSpace` size must be table of >= `1024` unsigned
++ */
++size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace);
++
++/* FSE_countFast_wksp() :
++ * Same as FSE_countFast(), but using an externally provided scratch buffer.
++ * `workSpace` must be a table of minimum `1024` unsigned
++ */
++size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize, unsigned *workSpace);
++
++/*! FSE_count_simple
++ * Same as FSE_countFast(), but does not use any additional memory (not even on stack).
++ * This function is unsafe, and will segfault if any value within `src` is `> *maxSymbolValuePtr` (presuming it's also the size of `count`).
++*/
++size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize);
++
++unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus);
++/**< same as FSE_optimalTableLog(), which used `minus==2` */
++
++size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits);
++/**< build a fake FSE_CTable, designed for a flat distribution, where each symbol uses nbBits */
++
++size_t FSE_buildCTable_rle(FSE_CTable *ct, unsigned char symbolValue);
++/**< build a fake FSE_CTable, designed to compress always the same symbolValue */
++
++/* FSE_buildCTable_wksp() :
++ * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`).
++ * `wkspSize` must be >= `(1<<tableLog)`.
++ */
++size_t FSE_buildCTable_wksp(FSE_CTable *ct, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, size_t wkspSize);
++
++size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits);
++/**< build a fake FSE_DTable, designed to read a flat distribution where each symbol uses nbBits */
++
++size_t FSE_buildDTable_rle(FSE_DTable *dt, unsigned char symbolValue);
++/**< build a fake FSE_DTable, designed to always generate the same symbolValue */
++
++size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize);
++/**< same as FSE_decompress(), using an externally allocated `workSpace` produced with `FSE_DTABLE_SIZE_U32(maxLog)` */
++
++/* *****************************************
++* FSE symbol compression API
++*******************************************/
++/*!
++ This API consists of small unitary functions, which highly benefit from being inlined.
++ Hence their body are included in next section.
++*/
++typedef struct {
++ ptrdiff_t value;
++ const void *stateTable;
++ const void *symbolTT;
++ unsigned stateLog;
++} FSE_CState_t;
++
++static void FSE_initCState(FSE_CState_t *CStatePtr, const FSE_CTable *ct);
++
++static void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *CStatePtr, unsigned symbol);
++
++static void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *CStatePtr);
++
++/**<
++These functions are inner components of FSE_compress_usingCTable().
++They allow the creation of custom streams, mixing multiple tables and bit sources.
++
++A key property to keep in mind is that encoding and decoding are done **in reverse direction**.
++So the first symbol you will encode is the last you will decode, like a LIFO stack.
++
++You will need a few variables to track your CStream. They are :
++
++FSE_CTable ct; // Provided by FSE_buildCTable()
++BIT_CStream_t bitStream; // bitStream tracking structure
++FSE_CState_t state; // State tracking structure (can have several)
++
++
++The first thing to do is to init bitStream and state.
++ size_t errorCode = BIT_initCStream(&bitStream, dstBuffer, maxDstSize);
++ FSE_initCState(&state, ct);
++
++Note that BIT_initCStream() can produce an error code, so its result should be tested, using FSE_isError();
++You can then encode your input data, byte after byte.
++FSE_encodeSymbol() outputs a maximum of 'tableLog' bits at a time.
++Remember decoding will be done in reverse direction.
++ FSE_encodeByte(&bitStream, &state, symbol);
++
++At any time, you can also add any bit sequence.
++Note : maximum allowed nbBits is 25, for compatibility with 32-bits decoders
++ BIT_addBits(&bitStream, bitField, nbBits);
++
++The above methods don't commit data to memory, they just store it into local register, for speed.
++Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
++Writing data to memory is a manual operation, performed by the flushBits function.
++ BIT_flushBits(&bitStream);
++
++Your last FSE encoding operation shall be to flush your last state value(s).
++ FSE_flushState(&bitStream, &state);
++
++Finally, you must close the bitStream.
++The function returns the size of CStream in bytes.
++If data couldn't fit into dstBuffer, it will return a 0 ( == not compressible)
++If there is an error, it returns an errorCode (which can be tested using FSE_isError()).
++ size_t size = BIT_closeCStream(&bitStream);
++*/
++
++/* *****************************************
++* FSE symbol decompression API
++*******************************************/
++typedef struct {
++ size_t state;
++ const void *table; /* precise table may vary, depending on U16 */
++} FSE_DState_t;
++
++static void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt);
++
++static unsigned char FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD);
++
++static unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr);
++
++/**<
++Let's now decompose FSE_decompress_usingDTable() into its unitary components.
++You will decode FSE-encoded symbols from the bitStream,
++and also any other bitFields you put in, **in reverse order**.
++
++You will need a few variables to track your bitStream. They are :
++
++BIT_DStream_t DStream; // Stream context
++FSE_DState_t DState; // State context. Multiple ones are possible
++FSE_DTable* DTablePtr; // Decoding table, provided by FSE_buildDTable()
++
++The first thing to do is to init the bitStream.
++ errorCode = BIT_initDStream(&DStream, srcBuffer, srcSize);
++
++You should then retrieve your initial state(s)
++(in reverse flushing order if you have several ones) :
++ errorCode = FSE_initDState(&DState, &DStream, DTablePtr);
++
++You can then decode your data, symbol after symbol.
++For information the maximum number of bits read by FSE_decodeSymbol() is 'tableLog'.
++Keep in mind that symbols are decoded in reverse order, like a LIFO stack (last in, first out).
++ unsigned char symbol = FSE_decodeSymbol(&DState, &DStream);
++
++You can retrieve any bitfield you eventually stored into the bitStream (in reverse order)
++Note : maximum allowed nbBits is 25, for 32-bits compatibility
++ size_t bitField = BIT_readBits(&DStream, nbBits);
++
++All above operations only read from local register (which size depends on size_t).
++Refueling the register from memory is manually performed by the reload method.
++ endSignal = FSE_reloadDStream(&DStream);
++
++BIT_reloadDStream() result tells if there is still some more data to read from DStream.
++BIT_DStream_unfinished : there is still some data left into the DStream.
++BIT_DStream_endOfBuffer : Dstream reached end of buffer. Its container may no longer be completely filled.
++BIT_DStream_completed : Dstream reached its exact end, corresponding in general to decompression completed.
++BIT_DStream_tooFar : Dstream went too far. Decompression result is corrupted.
++
++When reaching end of buffer (BIT_DStream_endOfBuffer), progress slowly, notably if you decode multiple symbols per loop,
++to properly detect the exact end of stream.
++After each decoded symbol, check if DStream is fully consumed using this simple test :
++ BIT_reloadDStream(&DStream) >= BIT_DStream_completed
++
++When it's done, verify decompression is fully completed, by checking both DStream and the relevant states.
++Checking if DStream has reached its end is performed by :
++ BIT_endOfDStream(&DStream);
++Check also the states. There might be some symbols left there, if some high probability ones (>50%) are possible.
++ FSE_endOfDState(&DState);
++*/
++
++/* *****************************************
++* FSE unsafe API
++*******************************************/
++static unsigned char FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD);
++/* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */
++
++/* *****************************************
++* Implementation of inlined functions
++*******************************************/
++typedef struct {
++ int deltaFindState;
++ U32 deltaNbBits;
++} FSE_symbolCompressionTransform; /* total 8 bytes */
++
++ZSTD_STATIC void FSE_initCState(FSE_CState_t *statePtr, const FSE_CTable *ct)
++{
++ const void *ptr = ct;
++ const U16 *u16ptr = (const U16 *)ptr;
++ const U32 tableLog = ZSTD_read16(ptr);
++ statePtr->value = (ptrdiff_t)1 << tableLog;
++ statePtr->stateTable = u16ptr + 2;
++ statePtr->symbolTT = ((const U32 *)ct + 1 + (tableLog ? (1 << (tableLog - 1)) : 1));
++ statePtr->stateLog = tableLog;
++}
++
++/*! FSE_initCState2() :
++* Same as FSE_initCState(), but the first symbol to include (which will be the last to be read)
++* uses the smallest state value possible, saving the cost of this symbol */
++ZSTD_STATIC void FSE_initCState2(FSE_CState_t *statePtr, const FSE_CTable *ct, U32 symbol)
++{
++ FSE_initCState(statePtr, ct);
++ {
++ const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol];
++ const U16 *stateTable = (const U16 *)(statePtr->stateTable);
++ U32 nbBitsOut = (U32)((symbolTT.deltaNbBits + (1 << 15)) >> 16);
++ statePtr->value = (nbBitsOut << 16) - symbolTT.deltaNbBits;
++ statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
++ }
++}
++
++ZSTD_STATIC void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *statePtr, U32 symbol)
++{
++ const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol];
++ const U16 *const stateTable = (const U16 *)(statePtr->stateTable);
++ U32 nbBitsOut = (U32)((statePtr->value + symbolTT.deltaNbBits) >> 16);
++ BIT_addBits(bitC, statePtr->value, nbBitsOut);
++ statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
++}
++
++ZSTD_STATIC void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *statePtr)
++{
++ BIT_addBits(bitC, statePtr->value, statePtr->stateLog);
++ BIT_flushBits(bitC);
++}
++
++/* ====== Decompression ====== */
++
++typedef struct {
++ U16 tableLog;
++ U16 fastMode;
++} FSE_DTableHeader; /* sizeof U32 */
++
++typedef struct {
++ unsigned short newState;
++ unsigned char symbol;
++ unsigned char nbBits;
++} FSE_decode_t; /* size == U32 */
++
++ZSTD_STATIC void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt)
++{
++ const void *ptr = dt;
++ const FSE_DTableHeader *const DTableH = (const FSE_DTableHeader *)ptr;
++ DStatePtr->state = BIT_readBits(bitD, DTableH->tableLog);
++ BIT_reloadDStream(bitD);
++ DStatePtr->table = dt + 1;
++}
++
++ZSTD_STATIC BYTE FSE_peekSymbol(const FSE_DState_t *DStatePtr)
++{
++ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
++ return DInfo.symbol;
++}
++
++ZSTD_STATIC void FSE_updateState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD)
++{
++ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
++ U32 const nbBits = DInfo.nbBits;
++ size_t const lowBits = BIT_readBits(bitD, nbBits);
++ DStatePtr->state = DInfo.newState + lowBits;
++}
++
++ZSTD_STATIC BYTE FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD)
++{
++ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
++ U32 const nbBits = DInfo.nbBits;
++ BYTE const symbol = DInfo.symbol;
++ size_t const lowBits = BIT_readBits(bitD, nbBits);
++
++ DStatePtr->state = DInfo.newState + lowBits;
++ return symbol;
++}
++
++/*! FSE_decodeSymbolFast() :
++ unsafe, only works if no symbol has a probability > 50% */
++ZSTD_STATIC BYTE FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD)
++{
++ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
++ U32 const nbBits = DInfo.nbBits;
++ BYTE const symbol = DInfo.symbol;
++ size_t const lowBits = BIT_readBitsFast(bitD, nbBits);
++
++ DStatePtr->state = DInfo.newState + lowBits;
++ return symbol;
++}
++
++ZSTD_STATIC unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr) { return DStatePtr->state == 0; }
++
++/* **************************************************************
++* Tuning parameters
++****************************************************************/
++/*!MEMORY_USAGE :
++* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
++* Increasing memory usage improves compression ratio
++* Reduced memory usage can improve speed, due to cache effect
++* Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */
++#ifndef FSE_MAX_MEMORY_USAGE
++#define FSE_MAX_MEMORY_USAGE 14
++#endif
++#ifndef FSE_DEFAULT_MEMORY_USAGE
++#define FSE_DEFAULT_MEMORY_USAGE 13
++#endif
++
++/*!FSE_MAX_SYMBOL_VALUE :
++* Maximum symbol value authorized.
++* Required for proper stack allocation */
++#ifndef FSE_MAX_SYMBOL_VALUE
++#define FSE_MAX_SYMBOL_VALUE 255
++#endif
++
++/* **************************************************************
++* template functions type & suffix
++****************************************************************/
++#define FSE_FUNCTION_TYPE BYTE
++#define FSE_FUNCTION_EXTENSION
++#define FSE_DECODE_TYPE FSE_decode_t
++
++/* ***************************************************************
++* Constants
++*****************************************************************/
++#define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE - 2)
++#define FSE_MAX_TABLESIZE (1U << FSE_MAX_TABLELOG)
++#define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE - 1)
++#define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE - 2)
++#define FSE_MIN_TABLELOG 5
++
++#define FSE_TABLELOG_ABSOLUTE_MAX 15
++#if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX
++#error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported"
++#endif
++
++#define FSE_TABLESTEP(tableSize) ((tableSize >> 1) + (tableSize >> 3) + 3)
++
++#endif /* FSE_H */
+diff --git a/lib/zstd/fse_compress.c b/lib/zstd/fse_compress.c
+new file mode 100644
+index 0000000..ef3d174
+--- /dev/null
++++ b/lib/zstd/fse_compress.c
+@@ -0,0 +1,795 @@
++/*
++ * FSE : Finite State Entropy encoder
++ * Copyright (C) 2013-2015, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++
++/* **************************************************************
++* Compiler specifics
++****************************************************************/
++#define FORCE_INLINE static __always_inline
++
++/* **************************************************************
++* Includes
++****************************************************************/
++#include "bitstream.h"
++#include "fse.h"
++#include <linux/compiler.h>
++#include <linux/kernel.h>
++#include <linux/math64.h>
++#include <linux/string.h> /* memcpy, memset */
++
++/* **************************************************************
++* Error Management
++****************************************************************/
++#define FSE_STATIC_ASSERT(c) \
++ { \
++ enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
++ } /* use only *after* variable declarations */
++
++/* **************************************************************
++* Templates
++****************************************************************/
++/*
++ designed to be included
++ for type-specific functions (template emulation in C)
++ Objective is to write these functions only once, for improved maintenance
++*/
++
++/* safety checks */
++#ifndef FSE_FUNCTION_EXTENSION
++#error "FSE_FUNCTION_EXTENSION must be defined"
++#endif
++#ifndef FSE_FUNCTION_TYPE
++#error "FSE_FUNCTION_TYPE must be defined"
++#endif
++
++/* Function names */
++#define FSE_CAT(X, Y) X##Y
++#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y)
++#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y)
++
++/* Function templates */
++
++/* FSE_buildCTable_wksp() :
++ * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`).
++ * wkspSize should be sized to handle worst case situation, which is `1<<max_tableLog * sizeof(FSE_FUNCTION_TYPE)`
++ * workSpace must also be properly aligned with FSE_FUNCTION_TYPE requirements
++ */
++size_t FSE_buildCTable_wksp(FSE_CTable *ct, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize)
++{
++ U32 const tableSize = 1 << tableLog;
++ U32 const tableMask = tableSize - 1;
++ void *const ptr = ct;
++ U16 *const tableU16 = ((U16 *)ptr) + 2;
++ void *const FSCT = ((U32 *)ptr) + 1 /* header */ + (tableLog ? tableSize >> 1 : 1);
++ FSE_symbolCompressionTransform *const symbolTT = (FSE_symbolCompressionTransform *)(FSCT);
++ U32 const step = FSE_TABLESTEP(tableSize);
++ U32 highThreshold = tableSize - 1;
++
++ U32 *cumul;
++ FSE_FUNCTION_TYPE *tableSymbol;
++ size_t spaceUsed32 = 0;
++
++ cumul = (U32 *)workspace + spaceUsed32;
++ spaceUsed32 += FSE_MAX_SYMBOL_VALUE + 2;
++ tableSymbol = (FSE_FUNCTION_TYPE *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(sizeof(FSE_FUNCTION_TYPE) * ((size_t)1 << tableLog), sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ /* CTable header */
++ tableU16[-2] = (U16)tableLog;
++ tableU16[-1] = (U16)maxSymbolValue;
++
++ /* For explanations on how to distribute symbol values over the table :
++ * http://fastcompression.blogspot.fr/2014/02/fse-distributing-symbol-values.html */
++
++ /* symbol start positions */
++ {
++ U32 u;
++ cumul[0] = 0;
++ for (u = 1; u <= maxSymbolValue + 1; u++) {
++ if (normalizedCounter[u - 1] == -1) { /* Low proba symbol */
++ cumul[u] = cumul[u - 1] + 1;
++ tableSymbol[highThreshold--] = (FSE_FUNCTION_TYPE)(u - 1);
++ } else {
++ cumul[u] = cumul[u - 1] + normalizedCounter[u - 1];
++ }
++ }
++ cumul[maxSymbolValue + 1] = tableSize + 1;
++ }
++
++ /* Spread symbols */
++ {
++ U32 position = 0;
++ U32 symbol;
++ for (symbol = 0; symbol <= maxSymbolValue; symbol++) {
++ int nbOccurences;
++ for (nbOccurences = 0; nbOccurences < normalizedCounter[symbol]; nbOccurences++) {
++ tableSymbol[position] = (FSE_FUNCTION_TYPE)symbol;
++ position = (position + step) & tableMask;
++ while (position > highThreshold)
++ position = (position + step) & tableMask; /* Low proba area */
++ }
++ }
++
++ if (position != 0)
++ return ERROR(GENERIC); /* Must have gone through all positions */
++ }
++
++ /* Build table */
++ {
++ U32 u;
++ for (u = 0; u < tableSize; u++) {
++ FSE_FUNCTION_TYPE s = tableSymbol[u]; /* note : static analyzer may not understand tableSymbol is properly initialized */
++ tableU16[cumul[s]++] = (U16)(tableSize + u); /* TableU16 : sorted by symbol order; gives next state value */
++ }
++ }
++
++ /* Build Symbol Transformation Table */
++ {
++ unsigned total = 0;
++ unsigned s;
++ for (s = 0; s <= maxSymbolValue; s++) {
++ switch (normalizedCounter[s]) {
++ case 0: break;
++
++ case -1:
++ case 1:
++ symbolTT[s].deltaNbBits = (tableLog << 16) - (1 << tableLog);
++ symbolTT[s].deltaFindState = total - 1;
++ total++;
++ break;
++ default: {
++ U32 const maxBitsOut = tableLog - BIT_highbit32(normalizedCounter[s] - 1);
++ U32 const minStatePlus = normalizedCounter[s] << maxBitsOut;
++ symbolTT[s].deltaNbBits = (maxBitsOut << 16) - minStatePlus;
++ symbolTT[s].deltaFindState = total - normalizedCounter[s];
++ total += normalizedCounter[s];
++ }
++ }
++ }
++ }
++
++ return 0;
++}
++
++/*-**************************************************************
++* FSE NCount encoding-decoding
++****************************************************************/
++size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog)
++{
++ size_t const maxHeaderSize = (((maxSymbolValue + 1) * tableLog) >> 3) + 3;
++ return maxSymbolValue ? maxHeaderSize : FSE_NCOUNTBOUND; /* maxSymbolValue==0 ? use default */
++}
++
++static size_t FSE_writeNCount_generic(void *header, size_t headerBufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog,
++ unsigned writeIsSafe)
++{
++ BYTE *const ostart = (BYTE *)header;
++ BYTE *out = ostart;
++ BYTE *const oend = ostart + headerBufferSize;
++ int nbBits;
++ const int tableSize = 1 << tableLog;
++ int remaining;
++ int threshold;
++ U32 bitStream;
++ int bitCount;
++ unsigned charnum = 0;
++ int previous0 = 0;
++
++ bitStream = 0;
++ bitCount = 0;
++ /* Table Size */
++ bitStream += (tableLog - FSE_MIN_TABLELOG) << bitCount;
++ bitCount += 4;
++
++ /* Init */
++ remaining = tableSize + 1; /* +1 for extra accuracy */
++ threshold = tableSize;
++ nbBits = tableLog + 1;
++
++ while (remaining > 1) { /* stops at 1 */
++ if (previous0) {
++ unsigned start = charnum;
++ while (!normalizedCounter[charnum])
++ charnum++;
++ while (charnum >= start + 24) {
++ start += 24;
++ bitStream += 0xFFFFU << bitCount;
++ if ((!writeIsSafe) && (out > oend - 2))
++ return ERROR(dstSize_tooSmall); /* Buffer overflow */
++ out[0] = (BYTE)bitStream;
++ out[1] = (BYTE)(bitStream >> 8);
++ out += 2;
++ bitStream >>= 16;
++ }
++ while (charnum >= start + 3) {
++ start += 3;
++ bitStream += 3 << bitCount;
++ bitCount += 2;
++ }
++ bitStream += (charnum - start) << bitCount;
++ bitCount += 2;
++ if (bitCount > 16) {
++ if ((!writeIsSafe) && (out > oend - 2))
++ return ERROR(dstSize_tooSmall); /* Buffer overflow */
++ out[0] = (BYTE)bitStream;
++ out[1] = (BYTE)(bitStream >> 8);
++ out += 2;
++ bitStream >>= 16;
++ bitCount -= 16;
++ }
++ }
++ {
++ int count = normalizedCounter[charnum++];
++ int const max = (2 * threshold - 1) - remaining;
++ remaining -= count < 0 ? -count : count;
++ count++; /* +1 for extra accuracy */
++ if (count >= threshold)
++ count += max; /* [0..max[ [max..threshold[ (...) [threshold+max 2*threshold[ */
++ bitStream += count << bitCount;
++ bitCount += nbBits;
++ bitCount -= (count < max);
++ previous0 = (count == 1);
++ if (remaining < 1)
++ return ERROR(GENERIC);
++ while (remaining < threshold)
++ nbBits--, threshold >>= 1;
++ }
++ if (bitCount > 16) {
++ if ((!writeIsSafe) && (out > oend - 2))
++ return ERROR(dstSize_tooSmall); /* Buffer overflow */
++ out[0] = (BYTE)bitStream;
++ out[1] = (BYTE)(bitStream >> 8);
++ out += 2;
++ bitStream >>= 16;
++ bitCount -= 16;
++ }
++ }
++
++ /* flush remaining bitStream */
++ if ((!writeIsSafe) && (out > oend - 2))
++ return ERROR(dstSize_tooSmall); /* Buffer overflow */
++ out[0] = (BYTE)bitStream;
++ out[1] = (BYTE)(bitStream >> 8);
++ out += (bitCount + 7) / 8;
++
++ if (charnum > maxSymbolValue + 1)
++ return ERROR(GENERIC);
++
++ return (out - ostart);
++}
++
++size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
++{
++ if (tableLog > FSE_MAX_TABLELOG)
++ return ERROR(tableLog_tooLarge); /* Unsupported */
++ if (tableLog < FSE_MIN_TABLELOG)
++ return ERROR(GENERIC); /* Unsupported */
++
++ if (bufferSize < FSE_NCountWriteBound(maxSymbolValue, tableLog))
++ return FSE_writeNCount_generic(buffer, bufferSize, normalizedCounter, maxSymbolValue, tableLog, 0);
++
++ return FSE_writeNCount_generic(buffer, bufferSize, normalizedCounter, maxSymbolValue, tableLog, 1);
++}
++
++/*-**************************************************************
++* Counting histogram
++****************************************************************/
++/*! FSE_count_simple
++ This function counts byte values within `src`, and store the histogram into table `count`.
++ It doesn't use any additional memory.
++ But this function is unsafe : it doesn't check that all values within `src` can fit into `count`.
++ For this reason, prefer using a table `count` with 256 elements.
++ @return : count of most numerous element
++*/
++size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize)
++{
++ const BYTE *ip = (const BYTE *)src;
++ const BYTE *const end = ip + srcSize;
++ unsigned maxSymbolValue = *maxSymbolValuePtr;
++ unsigned max = 0;
++
++ memset(count, 0, (maxSymbolValue + 1) * sizeof(*count));
++ if (srcSize == 0) {
++ *maxSymbolValuePtr = 0;
++ return 0;
++ }
++
++ while (ip < end)
++ count[*ip++]++;
++
++ while (!count[maxSymbolValue])
++ maxSymbolValue--;
++ *maxSymbolValuePtr = maxSymbolValue;
++
++ {
++ U32 s;
++ for (s = 0; s <= maxSymbolValue; s++)
++ if (count[s] > max)
++ max = count[s];
++ }
++
++ return (size_t)max;
++}
++
++/* FSE_count_parallel_wksp() :
++ * Same as FSE_count_parallel(), but using an externally provided scratch buffer.
++ * `workSpace` size must be a minimum of `1024 * sizeof(unsigned)`` */
++static size_t FSE_count_parallel_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned checkMax,
++ unsigned *const workSpace)
++{
++ const BYTE *ip = (const BYTE *)source;
++ const BYTE *const iend = ip + sourceSize;
++ unsigned maxSymbolValue = *maxSymbolValuePtr;
++ unsigned max = 0;
++ U32 *const Counting1 = workSpace;
++ U32 *const Counting2 = Counting1 + 256;
++ U32 *const Counting3 = Counting2 + 256;
++ U32 *const Counting4 = Counting3 + 256;
++
++ memset(Counting1, 0, 4 * 256 * sizeof(unsigned));
++
++ /* safety checks */
++ if (!sourceSize) {
++ memset(count, 0, maxSymbolValue + 1);
++ *maxSymbolValuePtr = 0;
++ return 0;
++ }
++ if (!maxSymbolValue)
++ maxSymbolValue = 255; /* 0 == default */
++
++ /* by stripes of 16 bytes */
++ {
++ U32 cached = ZSTD_read32(ip);
++ ip += 4;
++ while (ip < iend - 15) {
++ U32 c = cached;
++ cached = ZSTD_read32(ip);
++ ip += 4;
++ Counting1[(BYTE)c]++;
++ Counting2[(BYTE)(c >> 8)]++;
++ Counting3[(BYTE)(c >> 16)]++;
++ Counting4[c >> 24]++;
++ c = cached;
++ cached = ZSTD_read32(ip);
++ ip += 4;
++ Counting1[(BYTE)c]++;
++ Counting2[(BYTE)(c >> 8)]++;
++ Counting3[(BYTE)(c >> 16)]++;
++ Counting4[c >> 24]++;
++ c = cached;
++ cached = ZSTD_read32(ip);
++ ip += 4;
++ Counting1[(BYTE)c]++;
++ Counting2[(BYTE)(c >> 8)]++;
++ Counting3[(BYTE)(c >> 16)]++;
++ Counting4[c >> 24]++;
++ c = cached;
++ cached = ZSTD_read32(ip);
++ ip += 4;
++ Counting1[(BYTE)c]++;
++ Counting2[(BYTE)(c >> 8)]++;
++ Counting3[(BYTE)(c >> 16)]++;
++ Counting4[c >> 24]++;
++ }
++ ip -= 4;
++ }
++
++ /* finish last symbols */
++ while (ip < iend)
++ Counting1[*ip++]++;
++
++ if (checkMax) { /* verify stats will fit into destination table */
++ U32 s;
++ for (s = 255; s > maxSymbolValue; s--) {
++ Counting1[s] += Counting2[s] + Counting3[s] + Counting4[s];
++ if (Counting1[s])
++ return ERROR(maxSymbolValue_tooSmall);
++ }
++ }
++
++ {
++ U32 s;
++ for (s = 0; s <= maxSymbolValue; s++) {
++ count[s] = Counting1[s] + Counting2[s] + Counting3[s] + Counting4[s];
++ if (count[s] > max)
++ max = count[s];
++ }
++ }
++
++ while (!count[maxSymbolValue])
++ maxSymbolValue--;
++ *maxSymbolValuePtr = maxSymbolValue;
++ return (size_t)max;
++}
++
++/* FSE_countFast_wksp() :
++ * Same as FSE_countFast(), but using an externally provided scratch buffer.
++ * `workSpace` size must be table of >= `1024` unsigned */
++size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace)
++{
++ if (sourceSize < 1500)
++ return FSE_count_simple(count, maxSymbolValuePtr, source, sourceSize);
++ return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 0, workSpace);
++}
++
++/* FSE_count_wksp() :
++ * Same as FSE_count(), but using an externally provided scratch buffer.
++ * `workSpace` size must be table of >= `1024` unsigned */
++size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace)
++{
++ if (*maxSymbolValuePtr < 255)
++ return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 1, workSpace);
++ *maxSymbolValuePtr = 255;
++ return FSE_countFast_wksp(count, maxSymbolValuePtr, source, sourceSize, workSpace);
++}
++
++/*-**************************************************************
++* FSE Compression Code
++****************************************************************/
++/*! FSE_sizeof_CTable() :
++ FSE_CTable is a variable size structure which contains :
++ `U16 tableLog;`
++ `U16 maxSymbolValue;`
++ `U16 nextStateNumber[1 << tableLog];` // This size is variable
++ `FSE_symbolCompressionTransform symbolTT[maxSymbolValue+1];` // This size is variable
++Allocation is manual (C standard does not support variable-size structures).
++*/
++size_t FSE_sizeof_CTable(unsigned maxSymbolValue, unsigned tableLog)
++{
++ if (tableLog > FSE_MAX_TABLELOG)
++ return ERROR(tableLog_tooLarge);
++ return FSE_CTABLE_SIZE_U32(tableLog, maxSymbolValue) * sizeof(U32);
++}
++
++/* provides the minimum logSize to safely represent a distribution */
++static unsigned FSE_minTableLog(size_t srcSize, unsigned maxSymbolValue)
++{
++ U32 minBitsSrc = BIT_highbit32((U32)(srcSize - 1)) + 1;
++ U32 minBitsSymbols = BIT_highbit32(maxSymbolValue) + 2;
++ U32 minBits = minBitsSrc < minBitsSymbols ? minBitsSrc : minBitsSymbols;
++ return minBits;
++}
++
++unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus)
++{
++ U32 maxBitsSrc = BIT_highbit32((U32)(srcSize - 1)) - minus;
++ U32 tableLog = maxTableLog;
++ U32 minBits = FSE_minTableLog(srcSize, maxSymbolValue);
++ if (tableLog == 0)
++ tableLog = FSE_DEFAULT_TABLELOG;
++ if (maxBitsSrc < tableLog)
++ tableLog = maxBitsSrc; /* Accuracy can be reduced */
++ if (minBits > tableLog)
++ tableLog = minBits; /* Need a minimum to safely represent all symbol values */
++ if (tableLog < FSE_MIN_TABLELOG)
++ tableLog = FSE_MIN_TABLELOG;
++ if (tableLog > FSE_MAX_TABLELOG)
++ tableLog = FSE_MAX_TABLELOG;
++ return tableLog;
++}
++
++unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue)
++{
++ return FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 2);
++}
++
++/* Secondary normalization method.
++ To be used when primary method fails. */
++
++static size_t FSE_normalizeM2(short *norm, U32 tableLog, const unsigned *count, size_t total, U32 maxSymbolValue)
++{
++ short const NOT_YET_ASSIGNED = -2;
++ U32 s;
++ U32 distributed = 0;
++ U32 ToDistribute;
++
++ /* Init */
++ U32 const lowThreshold = (U32)(total >> tableLog);
++ U32 lowOne = (U32)((total * 3) >> (tableLog + 1));
++
++ for (s = 0; s <= maxSymbolValue; s++) {
++ if (count[s] == 0) {
++ norm[s] = 0;
++ continue;
++ }
++ if (count[s] <= lowThreshold) {
++ norm[s] = -1;
++ distributed++;
++ total -= count[s];
++ continue;
++ }
++ if (count[s] <= lowOne) {
++ norm[s] = 1;
++ distributed++;
++ total -= count[s];
++ continue;
++ }
++
++ norm[s] = NOT_YET_ASSIGNED;
++ }
++ ToDistribute = (1 << tableLog) - distributed;
++
++ if ((total / ToDistribute) > lowOne) {
++ /* risk of rounding to zero */
++ lowOne = (U32)((total * 3) / (ToDistribute * 2));
++ for (s = 0; s <= maxSymbolValue; s++) {
++ if ((norm[s] == NOT_YET_ASSIGNED) && (count[s] <= lowOne)) {
++ norm[s] = 1;
++ distributed++;
++ total -= count[s];
++ continue;
++ }
++ }
++ ToDistribute = (1 << tableLog) - distributed;
++ }
++
++ if (distributed == maxSymbolValue + 1) {
++ /* all values are pretty poor;
++ probably incompressible data (should have already been detected);
++ find max, then give all remaining points to max */
++ U32 maxV = 0, maxC = 0;
++ for (s = 0; s <= maxSymbolValue; s++)
++ if (count[s] > maxC)
++ maxV = s, maxC = count[s];
++ norm[maxV] += (short)ToDistribute;
++ return 0;
++ }
++
++ if (total == 0) {
++ /* all of the symbols were low enough for the lowOne or lowThreshold */
++ for (s = 0; ToDistribute > 0; s = (s + 1) % (maxSymbolValue + 1))
++ if (norm[s] > 0)
++ ToDistribute--, norm[s]++;
++ return 0;
++ }
++
++ {
++ U64 const vStepLog = 62 - tableLog;
++ U64 const mid = (1ULL << (vStepLog - 1)) - 1;
++ U64 const rStep = div_u64((((U64)1 << vStepLog) * ToDistribute) + mid, (U32)total); /* scale on remaining */
++ U64 tmpTotal = mid;
++ for (s = 0; s <= maxSymbolValue; s++) {
++ if (norm[s] == NOT_YET_ASSIGNED) {
++ U64 const end = tmpTotal + (count[s] * rStep);
++ U32 const sStart = (U32)(tmpTotal >> vStepLog);
++ U32 const sEnd = (U32)(end >> vStepLog);
++ U32 const weight = sEnd - sStart;
++ if (weight < 1)
++ return ERROR(GENERIC);
++ norm[s] = (short)weight;
++ tmpTotal = end;
++ }
++ }
++ }
++
++ return 0;
++}
++
++size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t total, unsigned maxSymbolValue)
++{
++ /* Sanity checks */
++ if (tableLog == 0)
++ tableLog = FSE_DEFAULT_TABLELOG;
++ if (tableLog < FSE_MIN_TABLELOG)
++ return ERROR(GENERIC); /* Unsupported size */
++ if (tableLog > FSE_MAX_TABLELOG)
++ return ERROR(tableLog_tooLarge); /* Unsupported size */
++ if (tableLog < FSE_minTableLog(total, maxSymbolValue))
++ return ERROR(GENERIC); /* Too small tableLog, compression potentially impossible */
++
++ {
++ U32 const rtbTable[] = {0, 473195, 504333, 520860, 550000, 700000, 750000, 830000};
++ U64 const scale = 62 - tableLog;
++ U64 const step = div_u64((U64)1 << 62, (U32)total); /* <== here, one division ! */
++ U64 const vStep = 1ULL << (scale - 20);
++ int stillToDistribute = 1 << tableLog;
++ unsigned s;
++ unsigned largest = 0;
++ short largestP = 0;
++ U32 lowThreshold = (U32)(total >> tableLog);
++
++ for (s = 0; s <= maxSymbolValue; s++) {
++ if (count[s] == total)
++ return 0; /* rle special case */
++ if (count[s] == 0) {
++ normalizedCounter[s] = 0;
++ continue;
++ }
++ if (count[s] <= lowThreshold) {
++ normalizedCounter[s] = -1;
++ stillToDistribute--;
++ } else {
++ short proba = (short)((count[s] * step) >> scale);
++ if (proba < 8) {
++ U64 restToBeat = vStep * rtbTable[proba];
++ proba += (count[s] * step) - ((U64)proba << scale) > restToBeat;
++ }
++ if (proba > largestP)
++ largestP = proba, largest = s;
++ normalizedCounter[s] = proba;
++ stillToDistribute -= proba;
++ }
++ }
++ if (-stillToDistribute >= (normalizedCounter[largest] >> 1)) {
++ /* corner case, need another normalization method */
++ size_t const errorCode = FSE_normalizeM2(normalizedCounter, tableLog, count, total, maxSymbolValue);
++ if (FSE_isError(errorCode))
++ return errorCode;
++ } else
++ normalizedCounter[largest] += (short)stillToDistribute;
++ }
++
++ return tableLog;
++}
++
++/* fake FSE_CTable, for raw (uncompressed) input */
++size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits)
++{
++ const unsigned tableSize = 1 << nbBits;
++ const unsigned tableMask = tableSize - 1;
++ const unsigned maxSymbolValue = tableMask;
++ void *const ptr = ct;
++ U16 *const tableU16 = ((U16 *)ptr) + 2;
++ void *const FSCT = ((U32 *)ptr) + 1 /* header */ + (tableSize >> 1); /* assumption : tableLog >= 1 */
++ FSE_symbolCompressionTransform *const symbolTT = (FSE_symbolCompressionTransform *)(FSCT);
++ unsigned s;
++
++ /* Sanity checks */
++ if (nbBits < 1)
++ return ERROR(GENERIC); /* min size */
++
++ /* header */
++ tableU16[-2] = (U16)nbBits;
++ tableU16[-1] = (U16)maxSymbolValue;
++
++ /* Build table */
++ for (s = 0; s < tableSize; s++)
++ tableU16[s] = (U16)(tableSize + s);
++
++ /* Build Symbol Transformation Table */
++ {
++ const U32 deltaNbBits = (nbBits << 16) - (1 << nbBits);
++ for (s = 0; s <= maxSymbolValue; s++) {
++ symbolTT[s].deltaNbBits = deltaNbBits;
++ symbolTT[s].deltaFindState = s - 1;
++ }
++ }
++
++ return 0;
++}
++
++/* fake FSE_CTable, for rle input (always same symbol) */
++size_t FSE_buildCTable_rle(FSE_CTable *ct, BYTE symbolValue)
++{
++ void *ptr = ct;
++ U16 *tableU16 = ((U16 *)ptr) + 2;
++ void *FSCTptr = (U32 *)ptr + 2;
++ FSE_symbolCompressionTransform *symbolTT = (FSE_symbolCompressionTransform *)FSCTptr;
++
++ /* header */
++ tableU16[-2] = (U16)0;
++ tableU16[-1] = (U16)symbolValue;
++
++ /* Build table */
++ tableU16[0] = 0;
++ tableU16[1] = 0; /* just in case */
++
++ /* Build Symbol Transformation Table */
++ symbolTT[symbolValue].deltaNbBits = 0;
++ symbolTT[symbolValue].deltaFindState = 0;
++
++ return 0;
++}
++
++static size_t FSE_compress_usingCTable_generic(void *dst, size_t dstSize, const void *src, size_t srcSize, const FSE_CTable *ct, const unsigned fast)
++{
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *ip = iend;
++
++ BIT_CStream_t bitC;
++ FSE_CState_t CState1, CState2;
++
++ /* init */
++ if (srcSize <= 2)
++ return 0;
++ {
++ size_t const initError = BIT_initCStream(&bitC, dst, dstSize);
++ if (FSE_isError(initError))
++ return 0; /* not enough space available to write a bitstream */
++ }
++
++#define FSE_FLUSHBITS(s) (fast ? BIT_flushBitsFast(s) : BIT_flushBits(s))
++
++ if (srcSize & 1) {
++ FSE_initCState2(&CState1, ct, *--ip);
++ FSE_initCState2(&CState2, ct, *--ip);
++ FSE_encodeSymbol(&bitC, &CState1, *--ip);
++ FSE_FLUSHBITS(&bitC);
++ } else {
++ FSE_initCState2(&CState2, ct, *--ip);
++ FSE_initCState2(&CState1, ct, *--ip);
++ }
++
++ /* join to mod 4 */
++ srcSize -= 2;
++ if ((sizeof(bitC.bitContainer) * 8 > FSE_MAX_TABLELOG * 4 + 7) && (srcSize & 2)) { /* test bit 2 */
++ FSE_encodeSymbol(&bitC, &CState2, *--ip);
++ FSE_encodeSymbol(&bitC, &CState1, *--ip);
++ FSE_FLUSHBITS(&bitC);
++ }
++
++ /* 2 or 4 encoding per loop */
++ while (ip > istart) {
++
++ FSE_encodeSymbol(&bitC, &CState2, *--ip);
++
++ if (sizeof(bitC.bitContainer) * 8 < FSE_MAX_TABLELOG * 2 + 7) /* this test must be static */
++ FSE_FLUSHBITS(&bitC);
++
++ FSE_encodeSymbol(&bitC, &CState1, *--ip);
++
++ if (sizeof(bitC.bitContainer) * 8 > FSE_MAX_TABLELOG * 4 + 7) { /* this test must be static */
++ FSE_encodeSymbol(&bitC, &CState2, *--ip);
++ FSE_encodeSymbol(&bitC, &CState1, *--ip);
++ }
++
++ FSE_FLUSHBITS(&bitC);
++ }
++
++ FSE_flushCState(&bitC, &CState2);
++ FSE_flushCState(&bitC, &CState1);
++ return BIT_closeCStream(&bitC);
++}
++
++size_t FSE_compress_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const FSE_CTable *ct)
++{
++ unsigned const fast = (dstSize >= FSE_BLOCKBOUND(srcSize));
++
++ if (fast)
++ return FSE_compress_usingCTable_generic(dst, dstSize, src, srcSize, ct, 1);
++ else
++ return FSE_compress_usingCTable_generic(dst, dstSize, src, srcSize, ct, 0);
++}
++
++size_t FSE_compressBound(size_t size) { return FSE_COMPRESSBOUND(size); }
+diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
+new file mode 100644
+index 0000000..a84300e
+--- /dev/null
++++ b/lib/zstd/fse_decompress.c
+@@ -0,0 +1,332 @@
++/*
++ * FSE : Finite State Entropy decoder
++ * Copyright (C) 2013-2015, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++
++/* **************************************************************
++* Compiler specifics
++****************************************************************/
++#define FORCE_INLINE static __always_inline
++
++/* **************************************************************
++* Includes
++****************************************************************/
++#include "bitstream.h"
++#include "fse.h"
++#include <linux/compiler.h>
++#include <linux/kernel.h>
++#include <linux/string.h> /* memcpy, memset */
++
++/* **************************************************************
++* Error Management
++****************************************************************/
++#define FSE_isError ERR_isError
++#define FSE_STATIC_ASSERT(c) \
++ { \
++ enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
++ } /* use only *after* variable declarations */
++
++/* check and forward error code */
++#define CHECK_F(f) \
++ { \
++ size_t const e = f; \
++ if (FSE_isError(e)) \
++ return e; \
++ }
++
++/* **************************************************************
++* Templates
++****************************************************************/
++/*
++ designed to be included
++ for type-specific functions (template emulation in C)
++ Objective is to write these functions only once, for improved maintenance
++*/
++
++/* safety checks */
++#ifndef FSE_FUNCTION_EXTENSION
++#error "FSE_FUNCTION_EXTENSION must be defined"
++#endif
++#ifndef FSE_FUNCTION_TYPE
++#error "FSE_FUNCTION_TYPE must be defined"
++#endif
++
++/* Function names */
++#define FSE_CAT(X, Y) X##Y
++#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y)
++#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y)
++
++/* Function templates */
++
++size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize)
++{
++ void *const tdPtr = dt + 1; /* because *dt is unsigned, 32-bits aligned on 32-bits */
++ FSE_DECODE_TYPE *const tableDecode = (FSE_DECODE_TYPE *)(tdPtr);
++ U16 *symbolNext = (U16 *)workspace;
++
++ U32 const maxSV1 = maxSymbolValue + 1;
++ U32 const tableSize = 1 << tableLog;
++ U32 highThreshold = tableSize - 1;
++
++ /* Sanity Checks */
++ if (workspaceSize < sizeof(U16) * (FSE_MAX_SYMBOL_VALUE + 1))
++ return ERROR(tableLog_tooLarge);
++ if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE)
++ return ERROR(maxSymbolValue_tooLarge);
++ if (tableLog > FSE_MAX_TABLELOG)
++ return ERROR(tableLog_tooLarge);
++
++ /* Init, lay down lowprob symbols */
++ {
++ FSE_DTableHeader DTableH;
++ DTableH.tableLog = (U16)tableLog;
++ DTableH.fastMode = 1;
++ {
++ S16 const largeLimit = (S16)(1 << (tableLog - 1));
++ U32 s;
++ for (s = 0; s < maxSV1; s++) {
++ if (normalizedCounter[s] == -1) {
++ tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s;
++ symbolNext[s] = 1;
++ } else {
++ if (normalizedCounter[s] >= largeLimit)
++ DTableH.fastMode = 0;
++ symbolNext[s] = normalizedCounter[s];
++ }
++ }
++ }
++ memcpy(dt, &DTableH, sizeof(DTableH));
++ }
++
++ /* Spread symbols */
++ {
++ U32 const tableMask = tableSize - 1;
++ U32 const step = FSE_TABLESTEP(tableSize);
++ U32 s, position = 0;
++ for (s = 0; s < maxSV1; s++) {
++ int i;
++ for (i = 0; i < normalizedCounter[s]; i++) {
++ tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s;
++ position = (position + step) & tableMask;
++ while (position > highThreshold)
++ position = (position + step) & tableMask; /* lowprob area */
++ }
++ }
++ if (position != 0)
++ return ERROR(GENERIC); /* position must reach all cells once, otherwise normalizedCounter is incorrect */
++ }
++
++ /* Build Decoding table */
++ {
++ U32 u;
++ for (u = 0; u < tableSize; u++) {
++ FSE_FUNCTION_TYPE const symbol = (FSE_FUNCTION_TYPE)(tableDecode[u].symbol);
++ U16 nextState = symbolNext[symbol]++;
++ tableDecode[u].nbBits = (BYTE)(tableLog - BIT_highbit32((U32)nextState));
++ tableDecode[u].newState = (U16)((nextState << tableDecode[u].nbBits) - tableSize);
++ }
++ }
++
++ return 0;
++}
++
++/*-*******************************************************
++* Decompression (Byte symbols)
++*********************************************************/
++size_t FSE_buildDTable_rle(FSE_DTable *dt, BYTE symbolValue)
++{
++ void *ptr = dt;
++ FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr;
++ void *dPtr = dt + 1;
++ FSE_decode_t *const cell = (FSE_decode_t *)dPtr;
++
++ DTableH->tableLog = 0;
++ DTableH->fastMode = 0;
++
++ cell->newState = 0;
++ cell->symbol = symbolValue;
++ cell->nbBits = 0;
++
++ return 0;
++}
++
++size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits)
++{
++ void *ptr = dt;
++ FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr;
++ void *dPtr = dt + 1;
++ FSE_decode_t *const dinfo = (FSE_decode_t *)dPtr;
++ const unsigned tableSize = 1 << nbBits;
++ const unsigned tableMask = tableSize - 1;
++ const unsigned maxSV1 = tableMask + 1;
++ unsigned s;
++
++ /* Sanity checks */
++ if (nbBits < 1)
++ return ERROR(GENERIC); /* min size */
++
++ /* Build Decoding Table */
++ DTableH->tableLog = (U16)nbBits;
++ DTableH->fastMode = 1;
++ for (s = 0; s < maxSV1; s++) {
++ dinfo[s].newState = 0;
++ dinfo[s].symbol = (BYTE)s;
++ dinfo[s].nbBits = (BYTE)nbBits;
++ }
++
++ return 0;
++}
++
++FORCE_INLINE size_t FSE_decompress_usingDTable_generic(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt,
++ const unsigned fast)
++{
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *op = ostart;
++ BYTE *const omax = op + maxDstSize;
++ BYTE *const olimit = omax - 3;
++
++ BIT_DStream_t bitD;
++ FSE_DState_t state1;
++ FSE_DState_t state2;
++
++ /* Init */
++ CHECK_F(BIT_initDStream(&bitD, cSrc, cSrcSize));
++
++ FSE_initDState(&state1, &bitD, dt);
++ FSE_initDState(&state2, &bitD, dt);
++
++#define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD)
++
++ /* 4 symbols per loop */
++ for (; (BIT_reloadDStream(&bitD) == BIT_DStream_unfinished) & (op < olimit); op += 4) {
++ op[0] = FSE_GETSYMBOL(&state1);
++
++ if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */
++ BIT_reloadDStream(&bitD);
++
++ op[1] = FSE_GETSYMBOL(&state2);
++
++ if (FSE_MAX_TABLELOG * 4 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */
++ {
++ if (BIT_reloadDStream(&bitD) > BIT_DStream_unfinished) {
++ op += 2;
++ break;
++ }
++ }
++
++ op[2] = FSE_GETSYMBOL(&state1);
++
++ if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */
++ BIT_reloadDStream(&bitD);
++
++ op[3] = FSE_GETSYMBOL(&state2);
++ }
++
++ /* tail */
++ /* note : BIT_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly BIT_DStream_completed */
++ while (1) {
++ if (op > (omax - 2))
++ return ERROR(dstSize_tooSmall);
++ *op++ = FSE_GETSYMBOL(&state1);
++ if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) {
++ *op++ = FSE_GETSYMBOL(&state2);
++ break;
++ }
++
++ if (op > (omax - 2))
++ return ERROR(dstSize_tooSmall);
++ *op++ = FSE_GETSYMBOL(&state2);
++ if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) {
++ *op++ = FSE_GETSYMBOL(&state1);
++ break;
++ }
++ }
++
++ return op - ostart;
++}
++
++size_t FSE_decompress_usingDTable(void *dst, size_t originalSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt)
++{
++ const void *ptr = dt;
++ const FSE_DTableHeader *DTableH = (const FSE_DTableHeader *)ptr;
++ const U32 fastMode = DTableH->fastMode;
++
++ /* select fast mode (static) */
++ if (fastMode)
++ return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1);
++ return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
++}
++
++size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize)
++{
++ const BYTE *const istart = (const BYTE *)cSrc;
++ const BYTE *ip = istart;
++ unsigned tableLog;
++ unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
++ size_t NCountLength;
++
++ FSE_DTable *dt;
++ short *counting;
++ size_t spaceUsed32 = 0;
++
++ FSE_STATIC_ASSERT(sizeof(FSE_DTable) == sizeof(U32));
++
++ dt = (FSE_DTable *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += FSE_DTABLE_SIZE_U32(maxLog);
++ counting = (short *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(sizeof(short) * (FSE_MAX_SYMBOL_VALUE + 1), sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ /* normal FSE decoding mode */
++ NCountLength = FSE_readNCount(counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
++ if (FSE_isError(NCountLength))
++ return NCountLength;
++ // if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong); /* too small input size; supposed to be already checked in NCountLength, only remaining
++ // case : NCountLength==cSrcSize */
++ if (tableLog > maxLog)
++ return ERROR(tableLog_tooLarge);
++ ip += NCountLength;
++ cSrcSize -= NCountLength;
++
++ CHECK_F(FSE_buildDTable_wksp(dt, counting, maxSymbolValue, tableLog, workspace, workspaceSize));
++
++ return FSE_decompress_usingDTable(dst, dstCapacity, ip, cSrcSize, dt); /* always return, even if it is an error code */
++}
+diff --git a/lib/zstd/huf.h b/lib/zstd/huf.h
+new file mode 100644
+index 0000000..2143da2
+--- /dev/null
++++ b/lib/zstd/huf.h
+@@ -0,0 +1,212 @@
++/*
++ * Huffman coder, part of New Generation Entropy library
++ * header file
++ * Copyright (C) 2013-2016, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++#ifndef HUF_H_298734234
++#define HUF_H_298734234
++
++/* *** Dependencies *** */
++#include <linux/types.h> /* size_t */
++
++/* *** Tool functions *** */
++#define HUF_BLOCKSIZE_MAX (128 * 1024) /**< maximum input size for a single block compressed with HUF_compress */
++size_t HUF_compressBound(size_t size); /**< maximum compressed size (worst case) */
++
++/* Error Management */
++unsigned HUF_isError(size_t code); /**< tells if a return value is an error code */
++
++/* *** Advanced function *** */
++
++/** HUF_compress4X_wksp() :
++* Same as HUF_compress2(), but uses externally allocated `workSpace`, which must be a table of >= 1024 unsigned */
++size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
++ size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
++
++/* *** Dependencies *** */
++#include "mem.h" /* U32 */
++
++/* *** Constants *** */
++#define HUF_TABLELOG_MAX 12 /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
++#define HUF_TABLELOG_DEFAULT 11 /* tableLog by default, when not specified */
++#define HUF_SYMBOLVALUE_MAX 255
++
++#define HUF_TABLELOG_ABSOLUTEMAX 15 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
++#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
++#error "HUF_TABLELOG_MAX is too large !"
++#endif
++
++/* ****************************************
++* Static allocation
++******************************************/
++/* HUF buffer bounds */
++#define HUF_CTABLEBOUND 129
++#define HUF_BLOCKBOUND(size) (size + (size >> 8) + 8) /* only true if incompressible pre-filtered with fast heuristic */
++#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
++
++/* static allocation of HUF's Compression Table */
++#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
++ U32 name##hb[maxSymbolValue + 1]; \
++ void *name##hv = &(name##hb); \
++ HUF_CElt *name = (HUF_CElt *)(name##hv) /* no final ; */
++
++/* static allocation of HUF's DTable */
++typedef U32 HUF_DTable;
++#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1 << (maxTableLog)))
++#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = {((U32)((maxTableLog)-1) * 0x01000001)}
++#define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = {((U32)(maxTableLog)*0x01000001)}
++
++/* The workspace must have alignment at least 4 and be at least this large */
++#define HUF_COMPRESS_WORKSPACE_SIZE (6 << 10)
++#define HUF_COMPRESS_WORKSPACE_SIZE_U32 (HUF_COMPRESS_WORKSPACE_SIZE / sizeof(U32))
++
++/* The workspace must have alignment at least 4 and be at least this large */
++#define HUF_DECOMPRESS_WORKSPACE_SIZE (3 << 10)
++#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))
++
++/* ****************************************
++* Advanced decompression functions
++******************************************/
++size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); /**< decodes RLE and uncompressed */
++size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
++ size_t workspaceSize); /**< considers RLE and uncompressed as errors */
++size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
++ size_t workspaceSize); /**< single-symbol decoder */
++size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
++ size_t workspaceSize); /**< double-symbols decoder */
++
++/* ****************************************
++* HUF detailed API
++******************************************/
++/*!
++HUF_compress() does the following:
++1. count symbol occurrence from source[] into table count[] using FSE_count()
++2. (optional) refine tableLog using HUF_optimalTableLog()
++3. build Huffman table from count using HUF_buildCTable()
++4. save Huffman table to memory buffer using HUF_writeCTable_wksp()
++5. encode the data stream using HUF_compress4X_usingCTable()
++
++The following API allows targeting specific sub-functions for advanced tasks.
++For example, it's possible to compress several blocks using the same 'CTable',
++or to save and regenerate 'CTable' using external methods.
++*/
++/* FSE_count() : find it within "fse.h" */
++unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue);
++typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */
++size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, unsigned maxSymbolValue, unsigned huffLog, void *workspace, size_t workspaceSize);
++size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable);
++
++typedef enum {
++ HUF_repeat_none, /**< Cannot use the previous table */
++ HUF_repeat_check, /**< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1,
++ 4}X_repeat */
++ HUF_repeat_valid /**< Can use the previous table and it is asumed to be valid */
++} HUF_repeat;
++/** HUF_compress4X_repeat() :
++* Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
++* If it uses hufTable it does not modify hufTable or repeat.
++* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
++* If preferRepeat then the old table will always be used if valid. */
++size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
++ size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat,
++ int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
++
++/** HUF_buildCTable_wksp() :
++ * Same as HUF_buildCTable(), but using externally allocated scratch buffer.
++ * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned.
++ */
++size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize);
++
++/*! HUF_readStats() :
++ Read compact Huffman tree, saved by HUF_writeCTable().
++ `huffWeight` is destination buffer.
++ @return : size read from `src` , or an error Code .
++ Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */
++size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize,
++ void *workspace, size_t workspaceSize);
++
++/** HUF_readCTable() :
++* Loading a CTable saved with HUF_writeCTable() */
++size_t HUF_readCTable_wksp(HUF_CElt *CTable, unsigned maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize);
++
++/*
++HUF_decompress() does the following:
++1. select the decompression algorithm (X2, X4) based on pre-computed heuristics
++2. build Huffman table from save, using HUF_readDTableXn()
++3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable
++*/
++
++/** HUF_selectDecoder() :
++* Tells which decoder is likely to decode faster,
++* based on a set of pre-determined metrics.
++* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 .
++* Assumption : 0 < cSrcSize < dstSize <= 128 KB */
++U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize);
++
++size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize);
++size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize);
++
++size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
++size_t HUF_decompress4X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
++size_t HUF_decompress4X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
++
++/* single stream variants */
++
++size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
++ size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
++size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable);
++/** HUF_compress1X_repeat() :
++* Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
++* If it uses hufTable it does not modify hufTable or repeat.
++* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
++* If preferRepeat then the old table will always be used if valid. */
++size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
++ size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat,
++ int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
++
++size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize);
++size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
++ size_t workspaceSize); /**< single-symbol decoder */
++size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
++ size_t workspaceSize); /**< double-symbols decoder */
++
++size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize,
++ const HUF_DTable *DTable); /**< automatic selection of sing or double symbol decoder, based on DTable */
++size_t HUF_decompress1X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
++size_t HUF_decompress1X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
++
++#endif /* HUF_H_298734234 */
+diff --git a/lib/zstd/huf_compress.c b/lib/zstd/huf_compress.c
+new file mode 100644
+index 0000000..40055a7
+--- /dev/null
++++ b/lib/zstd/huf_compress.c
+@@ -0,0 +1,770 @@
++/*
++ * Huffman encoder, part of New Generation Entropy library
++ * Copyright (C) 2013-2016, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++
++/* **************************************************************
++* Includes
++****************************************************************/
++#include "bitstream.h"
++#include "fse.h" /* header compression */
++#include "huf.h"
++#include <linux/kernel.h>
++#include <linux/string.h> /* memcpy, memset */
++
++/* **************************************************************
++* Error Management
++****************************************************************/
++#define HUF_STATIC_ASSERT(c) \
++ { \
++ enum { HUF_static_assert = 1 / (int)(!!(c)) }; \
++ } /* use only *after* variable declarations */
++#define CHECK_V_F(e, f) \
++ size_t const e = f; \
++ if (ERR_isError(e)) \
++ return f
++#define CHECK_F(f) \
++ { \
++ CHECK_V_F(_var_err__, f); \
++ }
++
++/* **************************************************************
++* Utils
++****************************************************************/
++unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue)
++{
++ return FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 1);
++}
++
++/* *******************************************************
++* HUF : Huffman block compression
++*********************************************************/
++/* HUF_compressWeights() :
++ * Same as FSE_compress(), but dedicated to huff0's weights compression.
++ * The use case needs much less stack memory.
++ * Note : all elements within weightTable are supposed to be <= HUF_TABLELOG_MAX.
++ */
++#define MAX_FSE_TABLELOG_FOR_HUFF_HEADER 6
++size_t HUF_compressWeights_wksp(void *dst, size_t dstSize, const void *weightTable, size_t wtSize, void *workspace, size_t workspaceSize)
++{
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *op = ostart;
++ BYTE *const oend = ostart + dstSize;
++
++ U32 maxSymbolValue = HUF_TABLELOG_MAX;
++ U32 tableLog = MAX_FSE_TABLELOG_FOR_HUFF_HEADER;
++
++ FSE_CTable *CTable;
++ U32 *count;
++ S16 *norm;
++ size_t spaceUsed32 = 0;
++
++ HUF_STATIC_ASSERT(sizeof(FSE_CTable) == sizeof(U32));
++
++ CTable = (FSE_CTable *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += FSE_CTABLE_SIZE_U32(MAX_FSE_TABLELOG_FOR_HUFF_HEADER, HUF_TABLELOG_MAX);
++ count = (U32 *)workspace + spaceUsed32;
++ spaceUsed32 += HUF_TABLELOG_MAX + 1;
++ norm = (S16 *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(sizeof(S16) * (HUF_TABLELOG_MAX + 1), sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ /* init conditions */
++ if (wtSize <= 1)
++ return 0; /* Not compressible */
++
++ /* Scan input and build symbol stats */
++ {
++ CHECK_V_F(maxCount, FSE_count_simple(count, &maxSymbolValue, weightTable, wtSize));
++ if (maxCount == wtSize)
++ return 1; /* only a single symbol in src : rle */
++ if (maxCount == 1)
++ return 0; /* each symbol present maximum once => not compressible */
++ }
++
++ tableLog = FSE_optimalTableLog(tableLog, wtSize, maxSymbolValue);
++ CHECK_F(FSE_normalizeCount(norm, tableLog, count, wtSize, maxSymbolValue));
++
++ /* Write table description header */
++ {
++ CHECK_V_F(hSize, FSE_writeNCount(op, oend - op, norm, maxSymbolValue, tableLog));
++ op += hSize;
++ }
++
++ /* Compress */
++ CHECK_F(FSE_buildCTable_wksp(CTable, norm, maxSymbolValue, tableLog, workspace, workspaceSize));
++ {
++ CHECK_V_F(cSize, FSE_compress_usingCTable(op, oend - op, weightTable, wtSize, CTable));
++ if (cSize == 0)
++ return 0; /* not enough space for compressed data */
++ op += cSize;
++ }
++
++ return op - ostart;
++}
++
++struct HUF_CElt_s {
++ U16 val;
++ BYTE nbBits;
++}; /* typedef'd to HUF_CElt within "huf.h" */
++
++/*! HUF_writeCTable_wksp() :
++ `CTable` : Huffman tree to save, using huf representation.
++ @return : size of saved CTable */
++size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, U32 maxSymbolValue, U32 huffLog, void *workspace, size_t workspaceSize)
++{
++ BYTE *op = (BYTE *)dst;
++ U32 n;
++
++ BYTE *bitsToWeight;
++ BYTE *huffWeight;
++ size_t spaceUsed32 = 0;
++
++ bitsToWeight = (BYTE *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(HUF_TABLELOG_MAX + 1, sizeof(U32)) >> 2;
++ huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX, sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ /* check conditions */
++ if (maxSymbolValue > HUF_SYMBOLVALUE_MAX)
++ return ERROR(maxSymbolValue_tooLarge);
++
++ /* convert to weight */
++ bitsToWeight[0] = 0;
++ for (n = 1; n < huffLog + 1; n++)
++ bitsToWeight[n] = (BYTE)(huffLog + 1 - n);
++ for (n = 0; n < maxSymbolValue; n++)
++ huffWeight[n] = bitsToWeight[CTable[n].nbBits];
++
++ /* attempt weights compression by FSE */
++ {
++ CHECK_V_F(hSize, HUF_compressWeights_wksp(op + 1, maxDstSize - 1, huffWeight, maxSymbolValue, workspace, workspaceSize));
++ if ((hSize > 1) & (hSize < maxSymbolValue / 2)) { /* FSE compressed */
++ op[0] = (BYTE)hSize;
++ return hSize + 1;
++ }
++ }
++
++ /* write raw values as 4-bits (max : 15) */
++ if (maxSymbolValue > (256 - 128))
++ return ERROR(GENERIC); /* should not happen : likely means source cannot be compressed */
++ if (((maxSymbolValue + 1) / 2) + 1 > maxDstSize)
++ return ERROR(dstSize_tooSmall); /* not enough space within dst buffer */
++ op[0] = (BYTE)(128 /*special case*/ + (maxSymbolValue - 1));
++ huffWeight[maxSymbolValue] = 0; /* to be sure it doesn't cause msan issue in final combination */
++ for (n = 0; n < maxSymbolValue; n += 2)
++ op[(n / 2) + 1] = (BYTE)((huffWeight[n] << 4) + huffWeight[n + 1]);
++ return ((maxSymbolValue + 1) / 2) + 1;
++}
++
++size_t HUF_readCTable_wksp(HUF_CElt *CTable, U32 maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
++{
++ U32 *rankVal;
++ BYTE *huffWeight;
++ U32 tableLog = 0;
++ U32 nbSymbols = 0;
++ size_t readSize;
++ size_t spaceUsed32 = 0;
++
++ rankVal = (U32 *)workspace + spaceUsed32;
++ spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1;
++ huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ /* get symbol weights */
++ readSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize);
++ if (ERR_isError(readSize))
++ return readSize;
++
++ /* check result */
++ if (tableLog > HUF_TABLELOG_MAX)
++ return ERROR(tableLog_tooLarge);
++ if (nbSymbols > maxSymbolValue + 1)
++ return ERROR(maxSymbolValue_tooSmall);
++
++ /* Prepare base value per rank */
++ {
++ U32 n, nextRankStart = 0;
++ for (n = 1; n <= tableLog; n++) {
++ U32 curr = nextRankStart;
++ nextRankStart += (rankVal[n] << (n - 1));
++ rankVal[n] = curr;
++ }
++ }
++
++ /* fill nbBits */
++ {
++ U32 n;
++ for (n = 0; n < nbSymbols; n++) {
++ const U32 w = huffWeight[n];
++ CTable[n].nbBits = (BYTE)(tableLog + 1 - w);
++ }
++ }
++
++ /* fill val */
++ {
++ U16 nbPerRank[HUF_TABLELOG_MAX + 2] = {0}; /* support w=0=>n=tableLog+1 */
++ U16 valPerRank[HUF_TABLELOG_MAX + 2] = {0};
++ {
++ U32 n;
++ for (n = 0; n < nbSymbols; n++)
++ nbPerRank[CTable[n].nbBits]++;
++ }
++ /* determine stating value per rank */
++ valPerRank[tableLog + 1] = 0; /* for w==0 */
++ {
++ U16 min = 0;
++ U32 n;
++ for (n = tableLog; n > 0; n--) { /* start at n=tablelog <-> w=1 */
++ valPerRank[n] = min; /* get starting value within each rank */
++ min += nbPerRank[n];
++ min >>= 1;
++ }
++ }
++ /* assign value within rank, symbol order */
++ {
++ U32 n;
++ for (n = 0; n <= maxSymbolValue; n++)
++ CTable[n].val = valPerRank[CTable[n].nbBits]++;
++ }
++ }
++
++ return readSize;
++}
++
++typedef struct nodeElt_s {
++ U32 count;
++ U16 parent;
++ BYTE byte;
++ BYTE nbBits;
++} nodeElt;
++
++static U32 HUF_setMaxHeight(nodeElt *huffNode, U32 lastNonNull, U32 maxNbBits)
++{
++ const U32 largestBits = huffNode[lastNonNull].nbBits;
++ if (largestBits <= maxNbBits)
++ return largestBits; /* early exit : no elt > maxNbBits */
++
++ /* there are several too large elements (at least >= 2) */
++ {
++ int totalCost = 0;
++ const U32 baseCost = 1 << (largestBits - maxNbBits);
++ U32 n = lastNonNull;
++
++ while (huffNode[n].nbBits > maxNbBits) {
++ totalCost += baseCost - (1 << (largestBits - huffNode[n].nbBits));
++ huffNode[n].nbBits = (BYTE)maxNbBits;
++ n--;
++ } /* n stops at huffNode[n].nbBits <= maxNbBits */
++ while (huffNode[n].nbBits == maxNbBits)
++ n--; /* n end at index of smallest symbol using < maxNbBits */
++
++ /* renorm totalCost */
++ totalCost >>= (largestBits - maxNbBits); /* note : totalCost is necessarily a multiple of baseCost */
++
++ /* repay normalized cost */
++ {
++ U32 const noSymbol = 0xF0F0F0F0;
++ U32 rankLast[HUF_TABLELOG_MAX + 2];
++ int pos;
++
++ /* Get pos of last (smallest) symbol per rank */
++ memset(rankLast, 0xF0, sizeof(rankLast));
++ {
++ U32 currNbBits = maxNbBits;
++ for (pos = n; pos >= 0; pos--) {
++ if (huffNode[pos].nbBits >= currNbBits)
++ continue;
++ currNbBits = huffNode[pos].nbBits; /* < maxNbBits */
++ rankLast[maxNbBits - currNbBits] = pos;
++ }
++ }
++
++ while (totalCost > 0) {
++ U32 nBitsToDecrease = BIT_highbit32(totalCost) + 1;
++ for (; nBitsToDecrease > 1; nBitsToDecrease--) {
++ U32 highPos = rankLast[nBitsToDecrease];
++ U32 lowPos = rankLast[nBitsToDecrease - 1];
++ if (highPos == noSymbol)
++ continue;
++ if (lowPos == noSymbol)
++ break;
++ {
++ U32 const highTotal = huffNode[highPos].count;
++ U32 const lowTotal = 2 * huffNode[lowPos].count;
++ if (highTotal <= lowTotal)
++ break;
++ }
++ }
++ /* only triggered when no more rank 1 symbol left => find closest one (note : there is necessarily at least one !) */
++ /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */
++ while ((nBitsToDecrease <= HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol))
++ nBitsToDecrease++;
++ totalCost -= 1 << (nBitsToDecrease - 1);
++ if (rankLast[nBitsToDecrease - 1] == noSymbol)
++ rankLast[nBitsToDecrease - 1] = rankLast[nBitsToDecrease]; /* this rank is no longer empty */
++ huffNode[rankLast[nBitsToDecrease]].nbBits++;
++ if (rankLast[nBitsToDecrease] == 0) /* special case, reached largest symbol */
++ rankLast[nBitsToDecrease] = noSymbol;
++ else {
++ rankLast[nBitsToDecrease]--;
++ if (huffNode[rankLast[nBitsToDecrease]].nbBits != maxNbBits - nBitsToDecrease)
++ rankLast[nBitsToDecrease] = noSymbol; /* this rank is now empty */
++ }
++ } /* while (totalCost > 0) */
++
++ while (totalCost < 0) { /* Sometimes, cost correction overshoot */
++ if (rankLast[1] == noSymbol) { /* special case : no rank 1 symbol (using maxNbBits-1); let's create one from largest rank 0
++ (using maxNbBits) */
++ while (huffNode[n].nbBits == maxNbBits)
++ n--;
++ huffNode[n + 1].nbBits--;
++ rankLast[1] = n + 1;
++ totalCost++;
++ continue;
++ }
++ huffNode[rankLast[1] + 1].nbBits--;
++ rankLast[1]++;
++ totalCost++;
++ }
++ }
++ } /* there are several too large elements (at least >= 2) */
++
++ return maxNbBits;
++}
++
++typedef struct {
++ U32 base;
++ U32 curr;
++} rankPos;
++
++static void HUF_sort(nodeElt *huffNode, const U32 *count, U32 maxSymbolValue)
++{
++ rankPos rank[32];
++ U32 n;
++
++ memset(rank, 0, sizeof(rank));
++ for (n = 0; n <= maxSymbolValue; n++) {
++ U32 r = BIT_highbit32(count[n] + 1);
++ rank[r].base++;
++ }
++ for (n = 30; n > 0; n--)
++ rank[n - 1].base += rank[n].base;
++ for (n = 0; n < 32; n++)
++ rank[n].curr = rank[n].base;
++ for (n = 0; n <= maxSymbolValue; n++) {
++ U32 const c = count[n];
++ U32 const r = BIT_highbit32(c + 1) + 1;
++ U32 pos = rank[r].curr++;
++ while ((pos > rank[r].base) && (c > huffNode[pos - 1].count))
++ huffNode[pos] = huffNode[pos - 1], pos--;
++ huffNode[pos].count = c;
++ huffNode[pos].byte = (BYTE)n;
++ }
++}
++
++/** HUF_buildCTable_wksp() :
++ * Same as HUF_buildCTable(), but using externally allocated scratch buffer.
++ * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned.
++ */
++#define STARTNODE (HUF_SYMBOLVALUE_MAX + 1)
++typedef nodeElt huffNodeTable[2 * HUF_SYMBOLVALUE_MAX + 1 + 1];
++size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize)
++{
++ nodeElt *const huffNode0 = (nodeElt *)workSpace;
++ nodeElt *const huffNode = huffNode0 + 1;
++ U32 n, nonNullRank;
++ int lowS, lowN;
++ U16 nodeNb = STARTNODE;
++ U32 nodeRoot;
++
++ /* safety checks */
++ if (wkspSize < sizeof(huffNodeTable))
++ return ERROR(GENERIC); /* workSpace is not large enough */
++ if (maxNbBits == 0)
++ maxNbBits = HUF_TABLELOG_DEFAULT;
++ if (maxSymbolValue > HUF_SYMBOLVALUE_MAX)
++ return ERROR(GENERIC);
++ memset(huffNode0, 0, sizeof(huffNodeTable));
++
++ /* sort, decreasing order */
++ HUF_sort(huffNode, count, maxSymbolValue);
++
++ /* init for parents */
++ nonNullRank = maxSymbolValue;
++ while (huffNode[nonNullRank].count == 0)
++ nonNullRank--;
++ lowS = nonNullRank;
++ nodeRoot = nodeNb + lowS - 1;
++ lowN = nodeNb;
++ huffNode[nodeNb].count = huffNode[lowS].count + huffNode[lowS - 1].count;
++ huffNode[lowS].parent = huffNode[lowS - 1].parent = nodeNb;
++ nodeNb++;
++ lowS -= 2;
++ for (n = nodeNb; n <= nodeRoot; n++)
++ huffNode[n].count = (U32)(1U << 30);
++ huffNode0[0].count = (U32)(1U << 31); /* fake entry, strong barrier */
++
++ /* create parents */
++ while (nodeNb <= nodeRoot) {
++ U32 n1 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++;
++ U32 n2 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++;
++ huffNode[nodeNb].count = huffNode[n1].count + huffNode[n2].count;
++ huffNode[n1].parent = huffNode[n2].parent = nodeNb;
++ nodeNb++;
++ }
++
++ /* distribute weights (unlimited tree height) */
++ huffNode[nodeRoot].nbBits = 0;
++ for (n = nodeRoot - 1; n >= STARTNODE; n--)
++ huffNode[n].nbBits = huffNode[huffNode[n].parent].nbBits + 1;
++ for (n = 0; n <= nonNullRank; n++)
++ huffNode[n].nbBits = huffNode[huffNode[n].parent].nbBits + 1;
++
++ /* enforce maxTableLog */
++ maxNbBits = HUF_setMaxHeight(huffNode, nonNullRank, maxNbBits);
++
++ /* fill result into tree (val, nbBits) */
++ {
++ U16 nbPerRank[HUF_TABLELOG_MAX + 1] = {0};
++ U16 valPerRank[HUF_TABLELOG_MAX + 1] = {0};
++ if (maxNbBits > HUF_TABLELOG_MAX)
++ return ERROR(GENERIC); /* check fit into table */
++ for (n = 0; n <= nonNullRank; n++)
++ nbPerRank[huffNode[n].nbBits]++;
++ /* determine stating value per rank */
++ {
++ U16 min = 0;
++ for (n = maxNbBits; n > 0; n--) {
++ valPerRank[n] = min; /* get starting value within each rank */
++ min += nbPerRank[n];
++ min >>= 1;
++ }
++ }
++ for (n = 0; n <= maxSymbolValue; n++)
++ tree[huffNode[n].byte].nbBits = huffNode[n].nbBits; /* push nbBits per symbol, symbol order */
++ for (n = 0; n <= maxSymbolValue; n++)
++ tree[n].val = valPerRank[tree[n].nbBits]++; /* assign value within rank, symbol order */
++ }
++
++ return maxNbBits;
++}
++
++static size_t HUF_estimateCompressedSize(HUF_CElt *CTable, const unsigned *count, unsigned maxSymbolValue)
++{
++ size_t nbBits = 0;
++ int s;
++ for (s = 0; s <= (int)maxSymbolValue; ++s) {
++ nbBits += CTable[s].nbBits * count[s];
++ }
++ return nbBits >> 3;
++}
++
++static int HUF_validateCTable(const HUF_CElt *CTable, const unsigned *count, unsigned maxSymbolValue)
++{
++ int bad = 0;
++ int s;
++ for (s = 0; s <= (int)maxSymbolValue; ++s) {
++ bad |= (count[s] != 0) & (CTable[s].nbBits == 0);
++ }
++ return !bad;
++}
++
++static void HUF_encodeSymbol(BIT_CStream_t *bitCPtr, U32 symbol, const HUF_CElt *CTable)
++{
++ BIT_addBitsFast(bitCPtr, CTable[symbol].val, CTable[symbol].nbBits);
++}
++
++size_t HUF_compressBound(size_t size) { return HUF_COMPRESSBOUND(size); }
++
++#define HUF_FLUSHBITS(s) BIT_flushBits(s)
++
++#define HUF_FLUSHBITS_1(stream) \
++ if (sizeof((stream)->bitContainer) * 8 < HUF_TABLELOG_MAX * 2 + 7) \
++ HUF_FLUSHBITS(stream)
++
++#define HUF_FLUSHBITS_2(stream) \
++ if (sizeof((stream)->bitContainer) * 8 < HUF_TABLELOG_MAX * 4 + 7) \
++ HUF_FLUSHBITS(stream)
++
++size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable)
++{
++ const BYTE *ip = (const BYTE *)src;
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstSize;
++ BYTE *op = ostart;
++ size_t n;
++ BIT_CStream_t bitC;
++
++ /* init */
++ if (dstSize < 8)
++ return 0; /* not enough space to compress */
++ {
++ size_t const initErr = BIT_initCStream(&bitC, op, oend - op);
++ if (HUF_isError(initErr))
++ return 0;
++ }
++
++ n = srcSize & ~3; /* join to mod 4 */
++ switch (srcSize & 3) {
++ case 3: HUF_encodeSymbol(&bitC, ip[n + 2], CTable); HUF_FLUSHBITS_2(&bitC);
++ case 2: HUF_encodeSymbol(&bitC, ip[n + 1], CTable); HUF_FLUSHBITS_1(&bitC);
++ case 1: HUF_encodeSymbol(&bitC, ip[n + 0], CTable); HUF_FLUSHBITS(&bitC);
++ case 0:
++ default:;
++ }
++
++ for (; n > 0; n -= 4) { /* note : n&3==0 at this stage */
++ HUF_encodeSymbol(&bitC, ip[n - 1], CTable);
++ HUF_FLUSHBITS_1(&bitC);
++ HUF_encodeSymbol(&bitC, ip[n - 2], CTable);
++ HUF_FLUSHBITS_2(&bitC);
++ HUF_encodeSymbol(&bitC, ip[n - 3], CTable);
++ HUF_FLUSHBITS_1(&bitC);
++ HUF_encodeSymbol(&bitC, ip[n - 4], CTable);
++ HUF_FLUSHBITS(&bitC);
++ }
++
++ return BIT_closeCStream(&bitC);
++}
++
++size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable)
++{
++ size_t const segmentSize = (srcSize + 3) / 4; /* first 3 segments */
++ const BYTE *ip = (const BYTE *)src;
++ const BYTE *const iend = ip + srcSize;
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstSize;
++ BYTE *op = ostart;
++
++ if (dstSize < 6 + 1 + 1 + 1 + 8)
++ return 0; /* minimum space to compress successfully */
++ if (srcSize < 12)
++ return 0; /* no saving possible : too small input */
++ op += 6; /* jumpTable */
++
++ {
++ CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, segmentSize, CTable));
++ if (cSize == 0)
++ return 0;
++ ZSTD_writeLE16(ostart, (U16)cSize);
++ op += cSize;
++ }
++
++ ip += segmentSize;
++ {
++ CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, segmentSize, CTable));
++ if (cSize == 0)
++ return 0;
++ ZSTD_writeLE16(ostart + 2, (U16)cSize);
++ op += cSize;
++ }
++
++ ip += segmentSize;
++ {
++ CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, segmentSize, CTable));
++ if (cSize == 0)
++ return 0;
++ ZSTD_writeLE16(ostart + 4, (U16)cSize);
++ op += cSize;
++ }
++
++ ip += segmentSize;
++ {
++ CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, iend - ip, CTable));
++ if (cSize == 0)
++ return 0;
++ op += cSize;
++ }
++
++ return op - ostart;
++}
++
++static size_t HUF_compressCTable_internal(BYTE *const ostart, BYTE *op, BYTE *const oend, const void *src, size_t srcSize, unsigned singleStream,
++ const HUF_CElt *CTable)
++{
++ size_t const cSize =
++ singleStream ? HUF_compress1X_usingCTable(op, oend - op, src, srcSize, CTable) : HUF_compress4X_usingCTable(op, oend - op, src, srcSize, CTable);
++ if (HUF_isError(cSize)) {
++ return cSize;
++ }
++ if (cSize == 0) {
++ return 0;
++ } /* uncompressible */
++ op += cSize;
++ /* check compressibility */
++ if ((size_t)(op - ostart) >= srcSize - 1) {
++ return 0;
++ }
++ return op - ostart;
++}
++
++/* `workSpace` must a table of at least 1024 unsigned */
++static size_t HUF_compress_internal(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog,
++ unsigned singleStream, void *workSpace, size_t wkspSize, HUF_CElt *oldHufTable, HUF_repeat *repeat, int preferRepeat)
++{
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstSize;
++ BYTE *op = ostart;
++
++ U32 *count;
++ size_t const countSize = sizeof(U32) * (HUF_SYMBOLVALUE_MAX + 1);
++ HUF_CElt *CTable;
++ size_t const CTableSize = sizeof(HUF_CElt) * (HUF_SYMBOLVALUE_MAX + 1);
++
++ /* checks & inits */
++ if (wkspSize < sizeof(huffNodeTable) + countSize + CTableSize)
++ return ERROR(GENERIC);
++ if (!srcSize)
++ return 0; /* Uncompressed (note : 1 means rle, so first byte must be correct) */
++ if (!dstSize)
++ return 0; /* cannot fit within dst budget */
++ if (srcSize > HUF_BLOCKSIZE_MAX)
++ return ERROR(srcSize_wrong); /* curr block size limit */
++ if (huffLog > HUF_TABLELOG_MAX)
++ return ERROR(tableLog_tooLarge);
++ if (!maxSymbolValue)
++ maxSymbolValue = HUF_SYMBOLVALUE_MAX;
++ if (!huffLog)
++ huffLog = HUF_TABLELOG_DEFAULT;
++
++ count = (U32 *)workSpace;
++ workSpace = (BYTE *)workSpace + countSize;
++ wkspSize -= countSize;
++ CTable = (HUF_CElt *)workSpace;
++ workSpace = (BYTE *)workSpace + CTableSize;
++ wkspSize -= CTableSize;
++
++ /* Heuristic : If we don't need to check the validity of the old table use the old table for small inputs */
++ if (preferRepeat && repeat && *repeat == HUF_repeat_valid) {
++ return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, oldHufTable);
++ }
++
++ /* Scan input and build symbol stats */
++ {
++ CHECK_V_F(largest, FSE_count_wksp(count, &maxSymbolValue, (const BYTE *)src, srcSize, (U32 *)workSpace));
++ if (largest == srcSize) {
++ *ostart = ((const BYTE *)src)[0];
++ return 1;
++ } /* single symbol, rle */
++ if (largest <= (srcSize >> 7) + 1)
++ return 0; /* Fast heuristic : not compressible enough */
++ }
++
++ /* Check validity of previous table */
++ if (repeat && *repeat == HUF_repeat_check && !HUF_validateCTable(oldHufTable, count, maxSymbolValue)) {
++ *repeat = HUF_repeat_none;
++ }
++ /* Heuristic : use existing table for small inputs */
++ if (preferRepeat && repeat && *repeat != HUF_repeat_none) {
++ return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, oldHufTable);
++ }
++
++ /* Build Huffman Tree */
++ huffLog = HUF_optimalTableLog(huffLog, srcSize, maxSymbolValue);
++ {
++ CHECK_V_F(maxBits, HUF_buildCTable_wksp(CTable, count, maxSymbolValue, huffLog, workSpace, wkspSize));
++ huffLog = (U32)maxBits;
++ /* Zero the unused symbols so we can check it for validity */
++ memset(CTable + maxSymbolValue + 1, 0, CTableSize - (maxSymbolValue + 1) * sizeof(HUF_CElt));
++ }
++
++ /* Write table description header */
++ {
++ CHECK_V_F(hSize, HUF_writeCTable_wksp(op, dstSize, CTable, maxSymbolValue, huffLog, workSpace, wkspSize));
++ /* Check if using the previous table will be beneficial */
++ if (repeat && *repeat != HUF_repeat_none) {
++ size_t const oldSize = HUF_estimateCompressedSize(oldHufTable, count, maxSymbolValue);
++ size_t const newSize = HUF_estimateCompressedSize(CTable, count, maxSymbolValue);
++ if (oldSize <= hSize + newSize || hSize + 12 >= srcSize) {
++ return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, oldHufTable);
++ }
++ }
++ /* Use the new table */
++ if (hSize + 12ul >= srcSize) {
++ return 0;
++ }
++ op += hSize;
++ if (repeat) {
++ *repeat = HUF_repeat_none;
++ }
++ if (oldHufTable) {
++ memcpy(oldHufTable, CTable, CTableSize);
++ } /* Save the new table */
++ }
++ return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, CTable);
++}
++
++size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace,
++ size_t wkspSize)
++{
++ return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 1 /* single stream */, workSpace, wkspSize, NULL, NULL, 0);
++}
++
++size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace,
++ size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, int preferRepeat)
++{
++ return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 1 /* single stream */, workSpace, wkspSize, hufTable, repeat,
++ preferRepeat);
++}
++
++size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace,
++ size_t wkspSize)
++{
++ return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 0 /* 4 streams */, workSpace, wkspSize, NULL, NULL, 0);
++}
++
++size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace,
++ size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, int preferRepeat)
++{
++ return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 0 /* 4 streams */, workSpace, wkspSize, hufTable, repeat,
++ preferRepeat);
++}
+diff --git a/lib/zstd/huf_decompress.c b/lib/zstd/huf_decompress.c
+new file mode 100644
+index 0000000..6526482
+--- /dev/null
++++ b/lib/zstd/huf_decompress.c
+@@ -0,0 +1,960 @@
++/*
++ * Huffman decoder, part of New Generation Entropy library
++ * Copyright (C) 2013-2016, Yann Collet.
++ *
++ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions are
++ * met:
++ *
++ * * Redistributions of source code must retain the above copyright
++ * notice, this list of conditions and the following disclaimer.
++ * * Redistributions in binary form must reproduce the above
++ * copyright notice, this list of conditions and the following disclaimer
++ * in the documentation and/or other materials provided with the
++ * distribution.
++ *
++ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
++ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
++ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
++ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
++ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
++ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
++ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
++ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
++ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ *
++ * You can contact the author at :
++ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
++ */
++
++/* **************************************************************
++* Compiler specifics
++****************************************************************/
++#define FORCE_INLINE static __always_inline
++
++/* **************************************************************
++* Dependencies
++****************************************************************/
++#include "bitstream.h" /* BIT_* */
++#include "fse.h" /* header compression */
++#include "huf.h"
++#include <linux/compiler.h>
++#include <linux/kernel.h>
++#include <linux/string.h> /* memcpy, memset */
++
++/* **************************************************************
++* Error Management
++****************************************************************/
++#define HUF_STATIC_ASSERT(c) \
++ { \
++ enum { HUF_static_assert = 1 / (int)(!!(c)) }; \
++ } /* use only *after* variable declarations */
++
++/*-***************************/
++/* generic DTableDesc */
++/*-***************************/
++
++typedef struct {
++ BYTE maxTableLog;
++ BYTE tableType;
++ BYTE tableLog;
++ BYTE reserved;
++} DTableDesc;
++
++static DTableDesc HUF_getDTableDesc(const HUF_DTable *table)
++{
++ DTableDesc dtd;
++ memcpy(&dtd, table, sizeof(dtd));
++ return dtd;
++}
++
++/*-***************************/
++/* single-symbol decoding */
++/*-***************************/
++
++typedef struct {
++ BYTE byte;
++ BYTE nbBits;
++} HUF_DEltX2; /* single-symbol decoding */
++
++size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
++{
++ U32 tableLog = 0;
++ U32 nbSymbols = 0;
++ size_t iSize;
++ void *const dtPtr = DTable + 1;
++ HUF_DEltX2 *const dt = (HUF_DEltX2 *)dtPtr;
++
++ U32 *rankVal;
++ BYTE *huffWeight;
++ size_t spaceUsed32 = 0;
++
++ rankVal = (U32 *)workspace + spaceUsed32;
++ spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1;
++ huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable));
++ /* memset(huffWeight, 0, sizeof(huffWeight)); */ /* is not necessary, even though some analyzer complain ... */
++
++ iSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize);
++ if (HUF_isError(iSize))
++ return iSize;
++
++ /* Table header */
++ {
++ DTableDesc dtd = HUF_getDTableDesc(DTable);
++ if (tableLog > (U32)(dtd.maxTableLog + 1))
++ return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */
++ dtd.tableType = 0;
++ dtd.tableLog = (BYTE)tableLog;
++ memcpy(DTable, &dtd, sizeof(dtd));
++ }
++
++ /* Calculate starting value for each rank */
++ {
++ U32 n, nextRankStart = 0;
++ for (n = 1; n < tableLog + 1; n++) {
++ U32 const curr = nextRankStart;
++ nextRankStart += (rankVal[n] << (n - 1));
++ rankVal[n] = curr;
++ }
++ }
++
++ /* fill DTable */
++ {
++ U32 n;
++ for (n = 0; n < nbSymbols; n++) {
++ U32 const w = huffWeight[n];
++ U32 const length = (1 << w) >> 1;
++ U32 u;
++ HUF_DEltX2 D;
++ D.byte = (BYTE)n;
++ D.nbBits = (BYTE)(tableLog + 1 - w);
++ for (u = rankVal[w]; u < rankVal[w] + length; u++)
++ dt[u] = D;
++ rankVal[w] += length;
++ }
++ }
++
++ return iSize;
++}
++
++static BYTE HUF_decodeSymbolX2(BIT_DStream_t *Dstream, const HUF_DEltX2 *dt, const U32 dtLog)
++{
++ size_t const val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */
++ BYTE const c = dt[val].byte;
++ BIT_skipBits(Dstream, dt[val].nbBits);
++ return c;
++}
++
++#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) *ptr++ = HUF_decodeSymbolX2(DStreamPtr, dt, dtLog)
++
++#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
++ if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \
++ HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
++
++#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
++ if (ZSTD_64bits()) \
++ HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
++
++FORCE_INLINE size_t HUF_decodeStreamX2(BYTE *p, BIT_DStream_t *const bitDPtr, BYTE *const pEnd, const HUF_DEltX2 *const dt, const U32 dtLog)
++{
++ BYTE *const pStart = p;
++
++ /* up to 4 symbols at a time */
++ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd - 4)) {
++ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
++ HUF_DECODE_SYMBOLX2_1(p, bitDPtr);
++ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
++ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
++ }
++
++ /* closer to the end */
++ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd))
++ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
++
++ /* no more data to retrieve from bitstream, hence no need to reload */
++ while (p < pEnd)
++ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
++
++ return pEnd - pStart;
++}
++
++static size_t HUF_decompress1X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ BYTE *op = (BYTE *)dst;
++ BYTE *const oend = op + dstSize;
++ const void *dtPtr = DTable + 1;
++ const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr;
++ BIT_DStream_t bitD;
++ DTableDesc const dtd = HUF_getDTableDesc(DTable);
++ U32 const dtLog = dtd.tableLog;
++
++ {
++ size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++
++ HUF_decodeStreamX2(op, &bitD, oend, dt, dtLog);
++
++ /* check */
++ if (!BIT_endOfDStream(&bitD))
++ return ERROR(corruption_detected);
++
++ return dstSize;
++}
++
++size_t HUF_decompress1X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ DTableDesc dtd = HUF_getDTableDesc(DTable);
++ if (dtd.tableType != 0)
++ return ERROR(GENERIC);
++ return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
++}
++
++size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ const BYTE *ip = (const BYTE *)cSrc;
++
++ size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize);
++ if (HUF_isError(hSize))
++ return hSize;
++ if (hSize >= cSrcSize)
++ return ERROR(srcSize_wrong);
++ ip += hSize;
++ cSrcSize -= hSize;
++
++ return HUF_decompress1X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx);
++}
++
++static size_t HUF_decompress4X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ /* Check */
++ if (cSrcSize < 10)
++ return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
++
++ {
++ const BYTE *const istart = (const BYTE *)cSrc;
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstSize;
++ const void *const dtPtr = DTable + 1;
++ const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr;
++
++ /* Init */
++ BIT_DStream_t bitD1;
++ BIT_DStream_t bitD2;
++ BIT_DStream_t bitD3;
++ BIT_DStream_t bitD4;
++ size_t const length1 = ZSTD_readLE16(istart);
++ size_t const length2 = ZSTD_readLE16(istart + 2);
++ size_t const length3 = ZSTD_readLE16(istart + 4);
++ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
++ const BYTE *const istart1 = istart + 6; /* jumpTable */
++ const BYTE *const istart2 = istart1 + length1;
++ const BYTE *const istart3 = istart2 + length2;
++ const BYTE *const istart4 = istart3 + length3;
++ const size_t segmentSize = (dstSize + 3) / 4;
++ BYTE *const opStart2 = ostart + segmentSize;
++ BYTE *const opStart3 = opStart2 + segmentSize;
++ BYTE *const opStart4 = opStart3 + segmentSize;
++ BYTE *op1 = ostart;
++ BYTE *op2 = opStart2;
++ BYTE *op3 = opStart3;
++ BYTE *op4 = opStart4;
++ U32 endSignal;
++ DTableDesc const dtd = HUF_getDTableDesc(DTable);
++ U32 const dtLog = dtd.tableLog;
++
++ if (length4 > cSrcSize)
++ return ERROR(corruption_detected); /* overflow */
++ {
++ size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++ {
++ size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++ {
++ size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++ {
++ size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++
++ /* 16-32 symbols per loop (4-8 symbols per stream) */
++ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
++ for (; (endSignal == BIT_DStream_unfinished) && (op4 < (oend - 7));) {
++ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
++ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
++ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
++ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
++ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
++ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
++ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
++ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
++ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
++ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
++ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
++ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
++ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
++ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
++ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
++ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
++ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
++ }
++
++ /* check corruption */
++ if (op1 > opStart2)
++ return ERROR(corruption_detected);
++ if (op2 > opStart3)
++ return ERROR(corruption_detected);
++ if (op3 > opStart4)
++ return ERROR(corruption_detected);
++ /* note : op4 supposed already verified within main loop */
++
++ /* finish bitStreams one by one */
++ HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog);
++ HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog);
++ HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog);
++ HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog);
++
++ /* check */
++ endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
++ if (!endSignal)
++ return ERROR(corruption_detected);
++
++ /* decoded size */
++ return dstSize;
++ }
++}
++
++size_t HUF_decompress4X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ DTableDesc dtd = HUF_getDTableDesc(DTable);
++ if (dtd.tableType != 0)
++ return ERROR(GENERIC);
++ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
++}
++
++size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ const BYTE *ip = (const BYTE *)cSrc;
++
++ size_t const hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize);
++ if (HUF_isError(hSize))
++ return hSize;
++ if (hSize >= cSrcSize)
++ return ERROR(srcSize_wrong);
++ ip += hSize;
++ cSrcSize -= hSize;
++
++ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
++}
++
++/* *************************/
++/* double-symbols decoding */
++/* *************************/
++typedef struct {
++ U16 sequence;
++ BYTE nbBits;
++ BYTE length;
++} HUF_DEltX4; /* double-symbols decoding */
++
++typedef struct {
++ BYTE symbol;
++ BYTE weight;
++} sortedSymbol_t;
++
++/* HUF_fillDTableX4Level2() :
++ * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */
++static void HUF_fillDTableX4Level2(HUF_DEltX4 *DTable, U32 sizeLog, const U32 consumed, const U32 *rankValOrigin, const int minWeight,
++ const sortedSymbol_t *sortedSymbols, const U32 sortedListSize, U32 nbBitsBaseline, U16 baseSeq)
++{
++ HUF_DEltX4 DElt;
++ U32 rankVal[HUF_TABLELOG_MAX + 1];
++
++ /* get pre-calculated rankVal */
++ memcpy(rankVal, rankValOrigin, sizeof(rankVal));
++
++ /* fill skipped values */
++ if (minWeight > 1) {
++ U32 i, skipSize = rankVal[minWeight];
++ ZSTD_writeLE16(&(DElt.sequence), baseSeq);
++ DElt.nbBits = (BYTE)(consumed);
++ DElt.length = 1;
++ for (i = 0; i < skipSize; i++)
++ DTable[i] = DElt;
++ }
++
++ /* fill DTable */
++ {
++ U32 s;
++ for (s = 0; s < sortedListSize; s++) { /* note : sortedSymbols already skipped */
++ const U32 symbol = sortedSymbols[s].symbol;
++ const U32 weight = sortedSymbols[s].weight;
++ const U32 nbBits = nbBitsBaseline - weight;
++ const U32 length = 1 << (sizeLog - nbBits);
++ const U32 start = rankVal[weight];
++ U32 i = start;
++ const U32 end = start + length;
++
++ ZSTD_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8)));
++ DElt.nbBits = (BYTE)(nbBits + consumed);
++ DElt.length = 2;
++ do {
++ DTable[i++] = DElt;
++ } while (i < end); /* since length >= 1 */
++
++ rankVal[weight] += length;
++ }
++ }
++}
++
++typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1];
++typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1];
++
++static void HUF_fillDTableX4(HUF_DEltX4 *DTable, const U32 targetLog, const sortedSymbol_t *sortedList, const U32 sortedListSize, const U32 *rankStart,
++ rankVal_t rankValOrigin, const U32 maxWeight, const U32 nbBitsBaseline)
++{
++ U32 rankVal[HUF_TABLELOG_MAX + 1];
++ const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */
++ const U32 minBits = nbBitsBaseline - maxWeight;
++ U32 s;
++
++ memcpy(rankVal, rankValOrigin, sizeof(rankVal));
++
++ /* fill DTable */
++ for (s = 0; s < sortedListSize; s++) {
++ const U16 symbol = sortedList[s].symbol;
++ const U32 weight = sortedList[s].weight;
++ const U32 nbBits = nbBitsBaseline - weight;
++ const U32 start = rankVal[weight];
++ const U32 length = 1 << (targetLog - nbBits);
++
++ if (targetLog - nbBits >= minBits) { /* enough room for a second symbol */
++ U32 sortedRank;
++ int minWeight = nbBits + scaleLog;
++ if (minWeight < 1)
++ minWeight = 1;
++ sortedRank = rankStart[minWeight];
++ HUF_fillDTableX4Level2(DTable + start, targetLog - nbBits, nbBits, rankValOrigin[nbBits], minWeight, sortedList + sortedRank,
++ sortedListSize - sortedRank, nbBitsBaseline, symbol);
++ } else {
++ HUF_DEltX4 DElt;
++ ZSTD_writeLE16(&(DElt.sequence), symbol);
++ DElt.nbBits = (BYTE)(nbBits);
++ DElt.length = 1;
++ {
++ U32 const end = start + length;
++ U32 u;
++ for (u = start; u < end; u++)
++ DTable[u] = DElt;
++ }
++ }
++ rankVal[weight] += length;
++ }
++}
++
++size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
++{
++ U32 tableLog, maxW, sizeOfSort, nbSymbols;
++ DTableDesc dtd = HUF_getDTableDesc(DTable);
++ U32 const maxTableLog = dtd.maxTableLog;
++ size_t iSize;
++ void *dtPtr = DTable + 1; /* force compiler to avoid strict-aliasing */
++ HUF_DEltX4 *const dt = (HUF_DEltX4 *)dtPtr;
++ U32 *rankStart;
++
++ rankValCol_t *rankVal;
++ U32 *rankStats;
++ U32 *rankStart0;
++ sortedSymbol_t *sortedSymbol;
++ BYTE *weightList;
++ size_t spaceUsed32 = 0;
++
++ HUF_STATIC_ASSERT((sizeof(rankValCol_t) & 3) == 0);
++
++ rankVal = (rankValCol_t *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2;
++ rankStats = (U32 *)workspace + spaceUsed32;
++ spaceUsed32 += HUF_TABLELOG_MAX + 1;
++ rankStart0 = (U32 *)workspace + spaceUsed32;
++ spaceUsed32 += HUF_TABLELOG_MAX + 2;
++ sortedSymbol = (sortedSymbol_t *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2;
++ weightList = (BYTE *)((U32 *)workspace + spaceUsed32);
++ spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
++
++ if ((spaceUsed32 << 2) > workspaceSize)
++ return ERROR(tableLog_tooLarge);
++ workspace = (U32 *)workspace + spaceUsed32;
++ workspaceSize -= (spaceUsed32 << 2);
++
++ rankStart = rankStart0 + 1;
++ memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1));
++
++ HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable)); /* if compiler fails here, assertion is wrong */
++ if (maxTableLog > HUF_TABLELOG_MAX)
++ return ERROR(tableLog_tooLarge);
++ /* memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */
++
++ iSize = HUF_readStats_wksp(weightList, HUF_SYMBOLVALUE_MAX + 1, rankStats, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize);
++ if (HUF_isError(iSize))
++ return iSize;
++
++ /* check result */
++ if (tableLog > maxTableLog)
++ return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */
++
++ /* find maxWeight */
++ for (maxW = tableLog; rankStats[maxW] == 0; maxW--) {
++ } /* necessarily finds a solution before 0 */
++
++ /* Get start index of each weight */
++ {
++ U32 w, nextRankStart = 0;
++ for (w = 1; w < maxW + 1; w++) {
++ U32 curr = nextRankStart;
++ nextRankStart += rankStats[w];
++ rankStart[w] = curr;
++ }
++ rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/
++ sizeOfSort = nextRankStart;
++ }
++
++ /* sort symbols by weight */
++ {
++ U32 s;
++ for (s = 0; s < nbSymbols; s++) {
++ U32 const w = weightList[s];
++ U32 const r = rankStart[w]++;
++ sortedSymbol[r].symbol = (BYTE)s;
++ sortedSymbol[r].weight = (BYTE)w;
++ }
++ rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */
++ }
++
++ /* Build rankVal */
++ {
++ U32 *const rankVal0 = rankVal[0];
++ {
++ int const rescale = (maxTableLog - tableLog) - 1; /* tableLog <= maxTableLog */
++ U32 nextRankVal = 0;
++ U32 w;
++ for (w = 1; w < maxW + 1; w++) {
++ U32 curr = nextRankVal;
++ nextRankVal += rankStats[w] << (w + rescale);
++ rankVal0[w] = curr;
++ }
++ }
++ {
++ U32 const minBits = tableLog + 1 - maxW;
++ U32 consumed;
++ for (consumed = minBits; consumed < maxTableLog - minBits + 1; consumed++) {
++ U32 *const rankValPtr = rankVal[consumed];
++ U32 w;
++ for (w = 1; w < maxW + 1; w++) {
++ rankValPtr[w] = rankVal0[w] >> consumed;
++ }
++ }
++ }
++ }
++
++ HUF_fillDTableX4(dt, maxTableLog, sortedSymbol, sizeOfSort, rankStart0, rankVal, maxW, tableLog + 1);
++
++ dtd.tableLog = (BYTE)maxTableLog;
++ dtd.tableType = 1;
++ memcpy(DTable, &dtd, sizeof(dtd));
++ return iSize;
++}
++
++static U32 HUF_decodeSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog)
++{
++ size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
++ memcpy(op, dt + val, 2);
++ BIT_skipBits(DStream, dt[val].nbBits);
++ return dt[val].length;
++}
++
++static U32 HUF_decodeLastSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog)
++{
++ size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
++ memcpy(op, dt + val, 1);
++ if (dt[val].length == 1)
++ BIT_skipBits(DStream, dt[val].nbBits);
++ else {
++ if (DStream->bitsConsumed < (sizeof(DStream->bitContainer) * 8)) {
++ BIT_skipBits(DStream, dt[val].nbBits);
++ if (DStream->bitsConsumed > (sizeof(DStream->bitContainer) * 8))
++ /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
++ DStream->bitsConsumed = (sizeof(DStream->bitContainer) * 8);
++ }
++ }
++ return 1;
++}
++
++#define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
++
++#define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \
++ if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \
++ ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
++
++#define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \
++ if (ZSTD_64bits()) \
++ ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
++
++FORCE_INLINE size_t HUF_decodeStreamX4(BYTE *p, BIT_DStream_t *bitDPtr, BYTE *const pEnd, const HUF_DEltX4 *const dt, const U32 dtLog)
++{
++ BYTE *const pStart = p;
++
++ /* up to 8 symbols at a time */
++ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd - (sizeof(bitDPtr->bitContainer) - 1))) {
++ HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
++ HUF_DECODE_SYMBOLX4_1(p, bitDPtr);
++ HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
++ HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
++ }
++
++ /* closer to end : up to 2 symbols at a time */
++ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd - 2))
++ HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
++
++ while (p <= pEnd - 2)
++ HUF_DECODE_SYMBOLX4_0(p, bitDPtr); /* no need to reload : reached the end of DStream */
++
++ if (p < pEnd)
++ p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog);
++
++ return p - pStart;
++}
++
++static size_t HUF_decompress1X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ BIT_DStream_t bitD;
++
++ /* Init */
++ {
++ size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++
++ /* decode */
++ {
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstSize;
++ const void *const dtPtr = DTable + 1; /* force compiler to not use strict-aliasing */
++ const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr;
++ DTableDesc const dtd = HUF_getDTableDesc(DTable);
++ HUF_decodeStreamX4(ostart, &bitD, oend, dt, dtd.tableLog);
++ }
++
++ /* check */
++ if (!BIT_endOfDStream(&bitD))
++ return ERROR(corruption_detected);
++
++ /* decoded size */
++ return dstSize;
++}
++
++size_t HUF_decompress1X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ DTableDesc dtd = HUF_getDTableDesc(DTable);
++ if (dtd.tableType != 1)
++ return ERROR(GENERIC);
++ return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
++}
++
++size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ const BYTE *ip = (const BYTE *)cSrc;
++
++ size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize);
++ if (HUF_isError(hSize))
++ return hSize;
++ if (hSize >= cSrcSize)
++ return ERROR(srcSize_wrong);
++ ip += hSize;
++ cSrcSize -= hSize;
++
++ return HUF_decompress1X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx);
++}
++
++static size_t HUF_decompress4X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ if (cSrcSize < 10)
++ return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
++
++ {
++ const BYTE *const istart = (const BYTE *)cSrc;
++ BYTE *const ostart = (BYTE *)dst;
++ BYTE *const oend = ostart + dstSize;
++ const void *const dtPtr = DTable + 1;
++ const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr;
++
++ /* Init */
++ BIT_DStream_t bitD1;
++ BIT_DStream_t bitD2;
++ BIT_DStream_t bitD3;
++ BIT_DStream_t bitD4;
++ size_t const length1 = ZSTD_readLE16(istart);
++ size_t const length2 = ZSTD_readLE16(istart + 2);
++ size_t const length3 = ZSTD_readLE16(istart + 4);
++ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
++ const BYTE *const istart1 = istart + 6; /* jumpTable */
++ const BYTE *const istart2 = istart1 + length1;
++ const BYTE *const istart3 = istart2 + length2;
++ const BYTE *const istart4 = istart3 + length3;
++ size_t const segmentSize = (dstSize + 3) / 4;
++ BYTE *const opStart2 = ostart + segmentSize;
++ BYTE *const opStart3 = opStart2 + segmentSize;
++ BYTE *const opStart4 = opStart3 + segmentSize;
++ BYTE *op1 = ostart;
++ BYTE *op2 = opStart2;
++ BYTE *op3 = opStart3;
++ BYTE *op4 = opStart4;
++ U32 endSignal;
++ DTableDesc const dtd = HUF_getDTableDesc(DTable);
++ U32 const dtLog = dtd.tableLog;
++
++ if (length4 > cSrcSize)
++ return ERROR(corruption_detected); /* overflow */
++ {
++ size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++ {
++ size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++ {
++ size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++ {
++ size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4);
++ if (HUF_isError(errorCode))
++ return errorCode;
++ }
++
++ /* 16-32 symbols per loop (4-8 symbols per stream) */
++ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
++ for (; (endSignal == BIT_DStream_unfinished) & (op4 < (oend - (sizeof(bitD4.bitContainer) - 1)));) {
++ HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
++ HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
++ HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
++ HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
++ HUF_DECODE_SYMBOLX4_1(op1, &bitD1);
++ HUF_DECODE_SYMBOLX4_1(op2, &bitD2);
++ HUF_DECODE_SYMBOLX4_1(op3, &bitD3);
++ HUF_DECODE_SYMBOLX4_1(op4, &bitD4);
++ HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
++ HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
++ HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
++ HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
++ HUF_DECODE_SYMBOLX4_0(op1, &bitD1);
++ HUF_DECODE_SYMBOLX4_0(op2, &bitD2);
++ HUF_DECODE_SYMBOLX4_0(op3, &bitD3);
++ HUF_DECODE_SYMBOLX4_0(op4, &bitD4);
++
++ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
++ }
++
++ /* check corruption */
++ if (op1 > opStart2)
++ return ERROR(corruption_detected);
++ if (op2 > opStart3)
++ return ERROR(corruption_detected);
++ if (op3 > opStart4)
++ return ERROR(corruption_detected);
++ /* note : op4 already verified within main loop */
++
++ /* finish bitStreams one by one */
++ HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog);
++ HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog);
++ HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog);
++ HUF_decodeStreamX4(op4, &bitD4, oend, dt, dtLog);
++
++ /* check */
++ {
++ U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
++ if (!endCheck)
++ return ERROR(corruption_detected);
++ }
++
++ /* decoded size */
++ return dstSize;
++ }
++}
++
++size_t HUF_decompress4X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ DTableDesc dtd = HUF_getDTableDesc(DTable);
++ if (dtd.tableType != 1)
++ return ERROR(GENERIC);
++ return HUF_decompress4X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
++}
++
++size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ const BYTE *ip = (const BYTE *)cSrc;
++
++ size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize);
++ if (HUF_isError(hSize))
++ return hSize;
++ if (hSize >= cSrcSize)
++ return ERROR(srcSize_wrong);
++ ip += hSize;
++ cSrcSize -= hSize;
++
++ return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
++}
++
++/* ********************************/
++/* Generic decompression selector */
++/* ********************************/
++
++size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ DTableDesc const dtd = HUF_getDTableDesc(DTable);
++ return dtd.tableType ? HUF_decompress1X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable)
++ : HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable);
++}
++
++size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
++{
++ DTableDesc const dtd = HUF_getDTableDesc(DTable);
++ return dtd.tableType ? HUF_decompress4X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable)
++ : HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable);
++}
++
++typedef struct {
++ U32 tableTime;
++ U32 decode256Time;
++} algo_time_t;
++static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] = {
++ /* single, double, quad */
++ {{0, 0}, {1, 1}, {2, 2}}, /* Q==0 : impossible */
++ {{0, 0}, {1, 1}, {2, 2}}, /* Q==1 : impossible */
++ {{38, 130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */
++ {{448, 128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */
++ {{556, 128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */
++ {{714, 128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */
++ {{883, 128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */
++ {{897, 128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */
++ {{926, 128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */
++ {{947, 128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */
++ {{1107, 128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */
++ {{1177, 128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */
++ {{1242, 128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */
++ {{1349, 128}, {2644, 106}, {5260, 106}}, /* Q ==13 : 81-87% */
++ {{1455, 128}, {2422, 124}, {4174, 124}}, /* Q ==14 : 87-93% */
++ {{722, 128}, {1891, 145}, {1936, 146}}, /* Q ==15 : 93-99% */
++};
++
++/** HUF_selectDecoder() :
++* Tells which decoder is likely to decode faster,
++* based on a set of pre-determined metrics.
++* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 .
++* Assumption : 0 < cSrcSize < dstSize <= 128 KB */
++U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize)
++{
++ /* decoder timing evaluation */
++ U32 const Q = (U32)(cSrcSize * 16 / dstSize); /* Q < 16 since dstSize > cSrcSize */
++ U32 const D256 = (U32)(dstSize >> 8);
++ U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256);
++ U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256);
++ DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, for cache eviction */
++
++ return DTime1 < DTime0;
++}
++
++typedef size_t (*decompressionAlgo)(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize);
++
++size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ /* validation checks */
++ if (dstSize == 0)
++ return ERROR(dstSize_tooSmall);
++ if (cSrcSize > dstSize)
++ return ERROR(corruption_detected); /* invalid */
++ if (cSrcSize == dstSize) {
++ memcpy(dst, cSrc, dstSize);
++ return dstSize;
++ } /* not compressed */
++ if (cSrcSize == 1) {
++ memset(dst, *(const BYTE *)cSrc, dstSize);
++ return dstSize;
++ } /* RLE */
++
++ {
++ U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
++ return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize)
++ : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize);
++ }
++}
++
++size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ /* validation checks */
++ if (dstSize == 0)
++ return ERROR(dstSize_tooSmall);
++ if ((cSrcSize >= dstSize) || (cSrcSize <= 1))
++ return ERROR(corruption_detected); /* invalid */
++
++ {
++ U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
++ return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize)
++ : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize);
++ }
++}
++
++size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
++{
++ /* validation checks */
++ if (dstSize == 0)
++ return ERROR(dstSize_tooSmall);
++ if (cSrcSize > dstSize)
++ return ERROR(corruption_detected); /* invalid */
++ if (cSrcSize == dstSize) {
++ memcpy(dst, cSrc, dstSize);
++ return dstSize;
++ } /* not compressed */
++ if (cSrcSize == 1) {
++ memset(dst, *(const BYTE *)cSrc, dstSize);
++ return dstSize;
++ } /* RLE */
++
++ {
++ U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
++ return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize)
++ : HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize);
++ }
++}
+diff --git a/lib/zstd/mem.h b/lib/zstd/mem.h
+new file mode 100644
+index 0000000..42a697b
+--- /dev/null
++++ b/lib/zstd/mem.h
+@@ -0,0 +1,149 @@
++/**
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++#ifndef MEM_H_MODULE
++#define MEM_H_MODULE
++
++/*-****************************************
++* Dependencies
++******************************************/
++#include <asm/unaligned.h>
++#include <linux/string.h> /* memcpy */
++#include <linux/types.h> /* size_t, ptrdiff_t */
++
++/*-****************************************
++* Compiler specifics
++******************************************/
++#define ZSTD_STATIC static __inline __attribute__((unused))
++
++/*-**************************************************************
++* Basic Types
++*****************************************************************/
++typedef uint8_t BYTE;
++typedef uint16_t U16;
++typedef int16_t S16;
++typedef uint32_t U32;
++typedef int32_t S32;
++typedef uint64_t U64;
++typedef int64_t S64;
++typedef ptrdiff_t iPtrDiff;
++typedef uintptr_t uPtrDiff;
++
++/*-**************************************************************
++* Memory I/O
++*****************************************************************/
++ZSTD_STATIC unsigned ZSTD_32bits(void) { return sizeof(size_t) == 4; }
++ZSTD_STATIC unsigned ZSTD_64bits(void) { return sizeof(size_t) == 8; }
++
++#if defined(__LITTLE_ENDIAN)
++#define ZSTD_LITTLE_ENDIAN 1
++#else
++#define ZSTD_LITTLE_ENDIAN 0
++#endif
++
++ZSTD_STATIC unsigned ZSTD_isLittleEndian(void) { return ZSTD_LITTLE_ENDIAN; }
++
++ZSTD_STATIC U16 ZSTD_read16(const void *memPtr) { return get_unaligned((const U16 *)memPtr); }
++
++ZSTD_STATIC U32 ZSTD_read32(const void *memPtr) { return get_unaligned((const U32 *)memPtr); }
++
++ZSTD_STATIC U64 ZSTD_read64(const void *memPtr) { return get_unaligned((const U64 *)memPtr); }
++
++ZSTD_STATIC size_t ZSTD_readST(const void *memPtr) { return get_unaligned((const size_t *)memPtr); }
++
++ZSTD_STATIC void ZSTD_write16(void *memPtr, U16 value) { put_unaligned(value, (U16 *)memPtr); }
++
++ZSTD_STATIC void ZSTD_write32(void *memPtr, U32 value) { put_unaligned(value, (U32 *)memPtr); }
++
++ZSTD_STATIC void ZSTD_write64(void *memPtr, U64 value) { put_unaligned(value, (U64 *)memPtr); }
++
++/*=== Little endian r/w ===*/
++
++ZSTD_STATIC U16 ZSTD_readLE16(const void *memPtr) { return get_unaligned_le16(memPtr); }
++
++ZSTD_STATIC void ZSTD_writeLE16(void *memPtr, U16 val) { put_unaligned_le16(val, memPtr); }
++
++ZSTD_STATIC U32 ZSTD_readLE24(const void *memPtr) { return ZSTD_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16); }
++
++ZSTD_STATIC void ZSTD_writeLE24(void *memPtr, U32 val)
++{
++ ZSTD_writeLE16(memPtr, (U16)val);
++ ((BYTE *)memPtr)[2] = (BYTE)(val >> 16);
++}
++
++ZSTD_STATIC U32 ZSTD_readLE32(const void *memPtr) { return get_unaligned_le32(memPtr); }
++
++ZSTD_STATIC void ZSTD_writeLE32(void *memPtr, U32 val32) { put_unaligned_le32(val32, memPtr); }
++
++ZSTD_STATIC U64 ZSTD_readLE64(const void *memPtr) { return get_unaligned_le64(memPtr); }
++
++ZSTD_STATIC void ZSTD_writeLE64(void *memPtr, U64 val64) { put_unaligned_le64(val64, memPtr); }
++
++ZSTD_STATIC size_t ZSTD_readLEST(const void *memPtr)
++{
++ if (ZSTD_32bits())
++ return (size_t)ZSTD_readLE32(memPtr);
++ else
++ return (size_t)ZSTD_readLE64(memPtr);
++}
++
++ZSTD_STATIC void ZSTD_writeLEST(void *memPtr, size_t val)
++{
++ if (ZSTD_32bits())
++ ZSTD_writeLE32(memPtr, (U32)val);
++ else
++ ZSTD_writeLE64(memPtr, (U64)val);
++}
++
++/*=== Big endian r/w ===*/
++
++ZSTD_STATIC U32 ZSTD_readBE32(const void *memPtr) { return get_unaligned_be32(memPtr); }
++
++ZSTD_STATIC void ZSTD_writeBE32(void *memPtr, U32 val32) { put_unaligned_be32(val32, memPtr); }
++
++ZSTD_STATIC U64 ZSTD_readBE64(const void *memPtr) { return get_unaligned_be64(memPtr); }
++
++ZSTD_STATIC void ZSTD_writeBE64(void *memPtr, U64 val64) { put_unaligned_be64(val64, memPtr); }
++
++ZSTD_STATIC size_t ZSTD_readBEST(const void *memPtr)
++{
++ if (ZSTD_32bits())
++ return (size_t)ZSTD_readBE32(memPtr);
++ else
++ return (size_t)ZSTD_readBE64(memPtr);
++}
++
++ZSTD_STATIC void ZSTD_writeBEST(void *memPtr, size_t val)
++{
++ if (ZSTD_32bits())
++ ZSTD_writeBE32(memPtr, (U32)val);
++ else
++ ZSTD_writeBE64(memPtr, (U64)val);
++}
++
++/* function safe only for comparisons */
++ZSTD_STATIC U32 ZSTD_readMINMATCH(const void *memPtr, U32 length)
++{
++ switch (length) {
++ default:
++ case 4: return ZSTD_read32(memPtr);
++ case 3:
++ if (ZSTD_isLittleEndian())
++ return ZSTD_read32(memPtr) << 8;
++ else
++ return ZSTD_read32(memPtr) >> 8;
++ }
++}
++
++#endif /* MEM_H_MODULE */
+diff --git a/lib/zstd/zstd_common.c b/lib/zstd/zstd_common.c
+new file mode 100644
+index 0000000..e5f06d7
+--- /dev/null
++++ b/lib/zstd/zstd_common.c
+@@ -0,0 +1,73 @@
++/**
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++/*-*************************************
++* Dependencies
++***************************************/
++#include "error_private.h"
++#include "zstd_internal.h" /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */
++#include <linux/kernel.h>
++
++/*=**************************************************************
++* Custom allocator
++****************************************************************/
++
++#define stack_push(stack, size) \
++ ({ \
++ void *const ptr = ZSTD_PTR_ALIGN((stack)->ptr); \
++ (stack)->ptr = (char *)ptr + (size); \
++ (stack)->ptr <= (stack)->end ? ptr : NULL; \
++ })
++
++ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize)
++{
++ ZSTD_customMem stackMem = {ZSTD_stackAlloc, ZSTD_stackFree, workspace};
++ ZSTD_stack *stack = (ZSTD_stack *)workspace;
++ /* Verify preconditions */
++ if (!workspace || workspaceSize < sizeof(ZSTD_stack) || workspace != ZSTD_PTR_ALIGN(workspace)) {
++ ZSTD_customMem error = {NULL, NULL, NULL};
++ return error;
++ }
++ /* Initialize the stack */
++ stack->ptr = workspace;
++ stack->end = (char *)workspace + workspaceSize;
++ stack_push(stack, sizeof(ZSTD_stack));
++ return stackMem;
++}
++
++void *ZSTD_stackAllocAll(void *opaque, size_t *size)
++{
++ ZSTD_stack *stack = (ZSTD_stack *)opaque;
++ *size = (BYTE const *)stack->end - (BYTE *)ZSTD_PTR_ALIGN(stack->ptr);
++ return stack_push(stack, *size);
++}
++
++void *ZSTD_stackAlloc(void *opaque, size_t size)
++{
++ ZSTD_stack *stack = (ZSTD_stack *)opaque;
++ return stack_push(stack, size);
++}
++void ZSTD_stackFree(void *opaque, void *address)
++{
++ (void)opaque;
++ (void)address;
++}
++
++void *ZSTD_malloc(size_t size, ZSTD_customMem customMem) { return customMem.customAlloc(customMem.opaque, size); }
++
++void ZSTD_free(void *ptr, ZSTD_customMem customMem)
++{
++ if (ptr != NULL)
++ customMem.customFree(customMem.opaque, ptr);
++}
+diff --git a/lib/zstd/zstd_internal.h b/lib/zstd/zstd_internal.h
+new file mode 100644
+index 0000000..a0fb83e
+--- /dev/null
++++ b/lib/zstd/zstd_internal.h
+@@ -0,0 +1,261 @@
++/**
++ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++#ifndef ZSTD_CCOMMON_H_MODULE
++#define ZSTD_CCOMMON_H_MODULE
++
++/*-*******************************************************
++* Compiler specifics
++*********************************************************/
++#define FORCE_INLINE static __always_inline
++#define FORCE_NOINLINE static noinline
++
++/*-*************************************
++* Dependencies
++***************************************/
++#include "error_private.h"
++#include "mem.h"
++#include <linux/compiler.h>
++#include <linux/kernel.h>
++#include <linux/xxhash.h>
++#include <linux/zstd.h>
++
++/*-*************************************
++* shared macros
++***************************************/
++#define MIN(a, b) ((a) < (b) ? (a) : (b))
++#define MAX(a, b) ((a) > (b) ? (a) : (b))
++#define CHECK_F(f) \
++ { \
++ size_t const errcod = f; \
++ if (ERR_isError(errcod)) \
++ return errcod; \
++ } /* check and Forward error code */
++#define CHECK_E(f, e) \
++ { \
++ size_t const errcod = f; \
++ if (ERR_isError(errcod)) \
++ return ERROR(e); \
++ } /* check and send Error code */
++#define ZSTD_STATIC_ASSERT(c) \
++ { \
++ enum { ZSTD_static_assert = 1 / (int)(!!(c)) }; \
++ }
++
++/*-*************************************
++* Common constants
++***************************************/
++#define ZSTD_OPT_NUM (1 << 12)
++#define ZSTD_DICT_MAGIC 0xEC30A437 /* v0.7+ */
++
++#define ZSTD_REP_NUM 3 /* number of repcodes */
++#define ZSTD_REP_CHECK (ZSTD_REP_NUM) /* number of repcodes to check by the optimal parser */
++#define ZSTD_REP_MOVE (ZSTD_REP_NUM - 1)
++#define ZSTD_REP_MOVE_OPT (ZSTD_REP_NUM)
++static const U32 repStartValue[ZSTD_REP_NUM] = {1, 4, 8};
++
++#define KB *(1 << 10)
++#define MB *(1 << 20)
++#define GB *(1U << 30)
++
++#define BIT7 128
++#define BIT6 64
++#define BIT5 32
++#define BIT4 16
++#define BIT1 2
++#define BIT0 1
++
++#define ZSTD_WINDOWLOG_ABSOLUTEMIN 10
++static const size_t ZSTD_fcs_fieldSize[4] = {0, 2, 4, 8};
++static const size_t ZSTD_did_fieldSize[4] = {0, 1, 2, 4};
++
++#define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */
++static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
++typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
++
++#define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
++#define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */
++
++#define HufLog 12
++typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
++
++#define LONGNBSEQ 0x7F00
++
++#define MINMATCH 3
++#define EQUAL_READ32 4
++
++#define Litbits 8
++#define MaxLit ((1 << Litbits) - 1)
++#define MaxML 52
++#define MaxLL 35
++#define MaxOff 28
++#define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */
++#define MLFSELog 9
++#define LLFSELog 9
++#define OffFSELog 8
++
++static const U32 LL_bits[MaxLL + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
++static const S16 LL_defaultNorm[MaxLL + 1] = {4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1, -1, -1, -1, -1};
++#define LL_DEFAULTNORMLOG 6 /* for static allocation */
++static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
++
++static const U32 ML_bits[MaxML + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
++ 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
++static const S16 ML_defaultNorm[MaxML + 1] = {1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
++ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1};
++#define ML_DEFAULTNORMLOG 6 /* for static allocation */
++static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG;
++
++static const S16 OF_defaultNorm[MaxOff + 1] = {1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1};
++#define OF_DEFAULTNORMLOG 5 /* for static allocation */
++static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
++
++/*-*******************************************
++* Shared functions to include for inlining
++*********************************************/
++ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) {
++ memcpy(dst, src, 8);
++}
++/*! ZSTD_wildcopy() :
++* custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */
++#define WILDCOPY_OVERLENGTH 8
++ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
++{
++ const BYTE* ip = (const BYTE*)src;
++ BYTE* op = (BYTE*)dst;
++ BYTE* const oend = op + length;
++ /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
++ * Avoid the bad case where the loop only runs once by handling the
++ * special case separately. This doesn't trigger the bug because it
++ * doesn't involve pointer/integer overflow.
++ */
++ if (length <= 8)
++ return ZSTD_copy8(dst, src);
++ do {
++ ZSTD_copy8(op, ip);
++ op += 8;
++ ip += 8;
++ } while (op < oend);
++}
++
++/*-*******************************************
++* Private interfaces
++*********************************************/
++typedef struct ZSTD_stats_s ZSTD_stats_t;
++
++typedef struct {
++ U32 off;
++ U32 len;
++} ZSTD_match_t;
++
++typedef struct {
++ U32 price;
++ U32 off;
++ U32 mlen;
++ U32 litlen;
++ U32 rep[ZSTD_REP_NUM];
++} ZSTD_optimal_t;
++
++typedef struct seqDef_s {
++ U32 offset;
++ U16 litLength;
++ U16 matchLength;
++} seqDef;
++
++typedef struct {
++ seqDef *sequencesStart;
++ seqDef *sequences;
++ BYTE *litStart;
++ BYTE *lit;
++ BYTE *llCode;
++ BYTE *mlCode;
++ BYTE *ofCode;
++ U32 longLengthID; /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
++ U32 longLengthPos;
++ /* opt */
++ ZSTD_optimal_t *priceTable;
++ ZSTD_match_t *matchTable;
++ U32 *matchLengthFreq;
++ U32 *litLengthFreq;
++ U32 *litFreq;
++ U32 *offCodeFreq;
++ U32 matchLengthSum;
++ U32 matchSum;
++ U32 litLengthSum;
++ U32 litSum;
++ U32 offCodeSum;
++ U32 log2matchLengthSum;
++ U32 log2matchSum;
++ U32 log2litLengthSum;
++ U32 log2litSum;
++ U32 log2offCodeSum;
++ U32 factor;
++ U32 staticPrices;
++ U32 cachedPrice;
++ U32 cachedLitLength;
++ const BYTE *cachedLiterals;
++} seqStore_t;
++
++const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx);
++void ZSTD_seqToCodes(const seqStore_t *seqStorePtr);
++int ZSTD_isSkipFrame(ZSTD_DCtx *dctx);
++
++/*= Custom memory allocation functions */
++typedef void *(*ZSTD_allocFunction)(void *opaque, size_t size);
++typedef void (*ZSTD_freeFunction)(void *opaque, void *address);
++typedef struct {
++ ZSTD_allocFunction customAlloc;
++ ZSTD_freeFunction customFree;
++ void *opaque;
++} ZSTD_customMem;
++
++void *ZSTD_malloc(size_t size, ZSTD_customMem customMem);
++void ZSTD_free(void *ptr, ZSTD_customMem customMem);
++
++/*====== stack allocation ======*/
++
++typedef struct {
++ void *ptr;
++ const void *end;
++} ZSTD_stack;
++
++#define ZSTD_ALIGN(x) ALIGN(x, sizeof(size_t))
++#define ZSTD_PTR_ALIGN(p) PTR_ALIGN(p, sizeof(size_t))
++
++ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize);
++
++void *ZSTD_stackAllocAll(void *opaque, size_t *size);
++void *ZSTD_stackAlloc(void *opaque, size_t size);
++void ZSTD_stackFree(void *opaque, void *address);
++
++/*====== common function ======*/
++
++ZSTD_STATIC U32 ZSTD_highbit32(U32 val) { return 31 - __builtin_clz(val); }
++
++/* hidden functions */
++
++/* ZSTD_invalidateRepCodes() :
++ * ensures next compression will not use repcodes from previous block.
++ * Note : only works with regular variant;
++ * do not use with extDict variant ! */
++void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx);
++
++size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx);
++size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx);
++size_t ZSTD_freeCDict(ZSTD_CDict *cdict);
++size_t ZSTD_freeDDict(ZSTD_DDict *cdict);
++size_t ZSTD_freeCStream(ZSTD_CStream *zcs);
++size_t ZSTD_freeDStream(ZSTD_DStream *zds);
++
++#endif /* ZSTD_CCOMMON_H_MODULE */
+diff --git a/lib/zstd/zstd_opt.h b/lib/zstd/zstd_opt.h
+new file mode 100644
+index 0000000..ecdd725
+--- /dev/null
++++ b/lib/zstd/zstd_opt.h
+@@ -0,0 +1,1012 @@
++/**
++ * Copyright (c) 2016-present, Przemyslaw Skibinski, Yann Collet, Facebook, Inc.
++ * All rights reserved.
++ *
++ * This source code is licensed under the BSD-style license found in the
++ * LICENSE file in the root directory of https://github.com/facebook/zstd.
++ *
++ * This program is free software; you can redistribute it and/or modify it under
++ * the terms of the GNU General Public License version 2 as published by the
++ * Free Software Foundation. This program is dual-licensed; you may select
++ * either version 2 of the GNU General Public License ("GPL") or BSD license
++ * ("BSD").
++ */
++
++/* Note : this file is intended to be included within zstd_compress.c */
++
++#ifndef ZSTD_OPT_H_91842398743
++#define ZSTD_OPT_H_91842398743
++
++#define ZSTD_LITFREQ_ADD 2
++#define ZSTD_FREQ_DIV 4
++#define ZSTD_MAX_PRICE (1 << 30)
++
++/*-*************************************
++* Price functions for optimal parser
++***************************************/
++FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t *ssPtr)
++{
++ ssPtr->log2matchLengthSum = ZSTD_highbit32(ssPtr->matchLengthSum + 1);
++ ssPtr->log2litLengthSum = ZSTD_highbit32(ssPtr->litLengthSum + 1);
++ ssPtr->log2litSum = ZSTD_highbit32(ssPtr->litSum + 1);
++ ssPtr->log2offCodeSum = ZSTD_highbit32(ssPtr->offCodeSum + 1);
++ ssPtr->factor = 1 + ((ssPtr->litSum >> 5) / ssPtr->litLengthSum) + ((ssPtr->litSum << 1) / (ssPtr->litSum + ssPtr->matchSum));
++}
++
++ZSTD_STATIC void ZSTD_rescaleFreqs(seqStore_t *ssPtr, const BYTE *src, size_t srcSize)
++{
++ unsigned u;
++
++ ssPtr->cachedLiterals = NULL;
++ ssPtr->cachedPrice = ssPtr->cachedLitLength = 0;
++ ssPtr->staticPrices = 0;
++
++ if (ssPtr->litLengthSum == 0) {
++ if (srcSize <= 1024)
++ ssPtr->staticPrices = 1;
++
++ for (u = 0; u <= MaxLit; u++)
++ ssPtr->litFreq[u] = 0;
++ for (u = 0; u < srcSize; u++)
++ ssPtr->litFreq[src[u]]++;
++
++ ssPtr->litSum = 0;
++ ssPtr->litLengthSum = MaxLL + 1;
++ ssPtr->matchLengthSum = MaxML + 1;
++ ssPtr->offCodeSum = (MaxOff + 1);
++ ssPtr->matchSum = (ZSTD_LITFREQ_ADD << Litbits);
++
++ for (u = 0; u <= MaxLit; u++) {
++ ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> ZSTD_FREQ_DIV);
++ ssPtr->litSum += ssPtr->litFreq[u];
++ }
++ for (u = 0; u <= MaxLL; u++)
++ ssPtr->litLengthFreq[u] = 1;
++ for (u = 0; u <= MaxML; u++)
++ ssPtr->matchLengthFreq[u] = 1;
++ for (u = 0; u <= MaxOff; u++)
++ ssPtr->offCodeFreq[u] = 1;
++ } else {
++ ssPtr->matchLengthSum = 0;
++ ssPtr->litLengthSum = 0;
++ ssPtr->offCodeSum = 0;
++ ssPtr->matchSum = 0;
++ ssPtr->litSum = 0;
++
++ for (u = 0; u <= MaxLit; u++) {
++ ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> (ZSTD_FREQ_DIV + 1));
++ ssPtr->litSum += ssPtr->litFreq[u];
++ }
++ for (u = 0; u <= MaxLL; u++) {
++ ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u] >> (ZSTD_FREQ_DIV + 1));
++ ssPtr->litLengthSum += ssPtr->litLengthFreq[u];
++ }
++ for (u = 0; u <= MaxML; u++) {
++ ssPtr->matchLengthFreq[u] = 1 + (ssPtr->matchLengthFreq[u] >> ZSTD_FREQ_DIV);
++ ssPtr->matchLengthSum += ssPtr->matchLengthFreq[u];
++ ssPtr->matchSum += ssPtr->matchLengthFreq[u] * (u + 3);
++ }
++ ssPtr->matchSum *= ZSTD_LITFREQ_ADD;
++ for (u = 0; u <= MaxOff; u++) {
++ ssPtr->offCodeFreq[u] = 1 + (ssPtr->offCodeFreq[u] >> ZSTD_FREQ_DIV);
++ ssPtr->offCodeSum += ssPtr->offCodeFreq[u];
++ }
++ }
++
++ ZSTD_setLog2Prices(ssPtr);
++}
++
++FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t *ssPtr, U32 litLength, const BYTE *literals)
++{
++ U32 price, u;
++
++ if (ssPtr->staticPrices)
++ return ZSTD_highbit32((U32)litLength + 1) + (litLength * 6);
++
++ if (litLength == 0)
++ return ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[0] + 1);
++
++ /* literals */
++ if (ssPtr->cachedLiterals == literals) {
++ U32 const additional = litLength - ssPtr->cachedLitLength;
++ const BYTE *literals2 = ssPtr->cachedLiterals + ssPtr->cachedLitLength;
++ price = ssPtr->cachedPrice + additional * ssPtr->log2litSum;
++ for (u = 0; u < additional; u++)
++ price -= ZSTD_highbit32(ssPtr->litFreq[literals2[u]] + 1);
++ ssPtr->cachedPrice = price;
++ ssPtr->cachedLitLength = litLength;
++ } else {
++ price = litLength * ssPtr->log2litSum;
++ for (u = 0; u < litLength; u++)
++ price -= ZSTD_highbit32(ssPtr->litFreq[literals[u]] + 1);
++
++ if (litLength >= 12) {
++ ssPtr->cachedLiterals = literals;
++ ssPtr->cachedPrice = price;
++ ssPtr->cachedLitLength = litLength;
++ }
++ }
++
++ /* literal Length */
++ {
++ const BYTE LL_deltaCode = 19;
++ const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
++ price += LL_bits[llCode] + ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[llCode] + 1);
++ }
++
++ return price;
++}
++
++FORCE_INLINE U32 ZSTD_getPrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength, const int ultra)
++{
++ /* offset */
++ U32 price;
++ BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1);
++
++ if (seqStorePtr->staticPrices)
++ return ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit32((U32)matchLength + 1) + 16 + offCode;
++
++ price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode] + 1);
++ if (!ultra && offCode >= 20)
++ price += (offCode - 19) * 2;
++
++ /* match Length */
++ {
++ const BYTE ML_deltaCode = 36;
++ const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
++ price += ML_bits[mlCode] + seqStorePtr->log2matchLengthSum - ZSTD_highbit32(seqStorePtr->matchLengthFreq[mlCode] + 1);
++ }
++
++ return price + ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->factor;
++}
++
++ZSTD_STATIC void ZSTD_updatePrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength)
++{
++ U32 u;
++
++ /* literals */
++ seqStorePtr->litSum += litLength * ZSTD_LITFREQ_ADD;
++ for (u = 0; u < litLength; u++)
++ seqStorePtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD;
++
++ /* literal Length */
++ {
++ const BYTE LL_deltaCode = 19;
++ const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
++ seqStorePtr->litLengthFreq[llCode]++;
++ seqStorePtr->litLengthSum++;
++ }
++
++ /* match offset */
++ {
++ BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1);
++ seqStorePtr->offCodeSum++;
++ seqStorePtr->offCodeFreq[offCode]++;
++ }
++
++ /* match Length */
++ {
++ const BYTE ML_deltaCode = 36;
++ const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
++ seqStorePtr->matchLengthFreq[mlCode]++;
++ seqStorePtr->matchLengthSum++;
++ }
++
++ ZSTD_setLog2Prices(seqStorePtr);
++}
++
++#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \
++ { \
++ while (last_pos < pos) { \
++ opt[last_pos + 1].price = ZSTD_MAX_PRICE; \
++ last_pos++; \
++ } \
++ opt[pos].mlen = mlen_; \
++ opt[pos].off = offset_; \
++ opt[pos].litlen = litlen_; \
++ opt[pos].price = price_; \
++ }
++
++/* Update hashTable3 up to ip (excluded)
++ Assumption : always within prefix (i.e. not within extDict) */
++FORCE_INLINE
++U32 ZSTD_insertAndFindFirstIndexHash3(ZSTD_CCtx *zc, const BYTE *ip)
++{
++ U32 *const hashTable3 = zc->hashTable3;
++ U32 const hashLog3 = zc->hashLog3;
++ const BYTE *const base = zc->base;
++ U32 idx = zc->nextToUpdate3;
++ const U32 target = zc->nextToUpdate3 = (U32)(ip - base);
++ const size_t hash3 = ZSTD_hash3Ptr(ip, hashLog3);
++
++ while (idx < target) {
++ hashTable3[ZSTD_hash3Ptr(base + idx, hashLog3)] = idx;
++ idx++;
++ }
++
++ return hashTable3[hash3];
++}
++
++/*-*************************************
++* Binary Tree search
++***************************************/
++static U32 ZSTD_insertBtAndGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, U32 nbCompares, const U32 mls, U32 extDict,
++ ZSTD_match_t *matches, const U32 minMatchLen)
++{
++ const BYTE *const base = zc->base;
++ const U32 curr = (U32)(ip - base);
++ const U32 hashLog = zc->params.cParams.hashLog;
++ const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
++ U32 *const hashTable = zc->hashTable;
++ U32 matchIndex = hashTable[h];
++ U32 *const bt = zc->chainTable;
++ const U32 btLog = zc->params.cParams.chainLog - 1;
++ const U32 btMask = (1U << btLog) - 1;
++ size_t commonLengthSmaller = 0, commonLengthLarger = 0;
++ const BYTE *const dictBase = zc->dictBase;
++ const U32 dictLimit = zc->dictLimit;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++ const BYTE *const prefixStart = base + dictLimit;
++ const U32 btLow = btMask >= curr ? 0 : curr - btMask;
++ const U32 windowLow = zc->lowLimit;
++ U32 *smallerPtr = bt + 2 * (curr & btMask);
++ U32 *largerPtr = bt + 2 * (curr & btMask) + 1;
++ U32 matchEndIdx = curr + 8;
++ U32 dummy32; /* to be nullified at the end */
++ U32 mnum = 0;
++
++ const U32 minMatch = (mls == 3) ? 3 : 4;
++ size_t bestLength = minMatchLen - 1;
++
++ if (minMatch == 3) { /* HC3 match finder */
++ U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(zc, ip);
++ if (matchIndex3 > windowLow && (curr - matchIndex3 < (1 << 18))) {
++ const BYTE *match;
++ size_t currMl = 0;
++ if ((!extDict) || matchIndex3 >= dictLimit) {
++ match = base + matchIndex3;
++ if (match[bestLength] == ip[bestLength])
++ currMl = ZSTD_count(ip, match, iLimit);
++ } else {
++ match = dictBase + matchIndex3;
++ if (ZSTD_readMINMATCH(match, MINMATCH) ==
++ ZSTD_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
++ currMl = ZSTD_count_2segments(ip + MINMATCH, match + MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH;
++ }
++
++ /* save best solution */
++ if (currMl > bestLength) {
++ bestLength = currMl;
++ matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex3;
++ matches[mnum].len = (U32)currMl;
++ mnum++;
++ if (currMl > ZSTD_OPT_NUM)
++ goto update;
++ if (ip + currMl == iLimit)
++ goto update; /* best possible, and avoid read overflow*/
++ }
++ }
++ }
++
++ hashTable[h] = curr; /* Update Hash Table */
++
++ while (nbCompares-- && (matchIndex > windowLow)) {
++ U32 *nextPtr = bt + 2 * (matchIndex & btMask);
++ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
++ const BYTE *match;
++
++ if ((!extDict) || (matchIndex + matchLength >= dictLimit)) {
++ match = base + matchIndex;
++ if (match[matchLength] == ip[matchLength]) {
++ matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iLimit) + 1;
++ }
++ } else {
++ match = dictBase + matchIndex;
++ matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iLimit, dictEnd, prefixStart);
++ if (matchIndex + matchLength >= dictLimit)
++ match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
++ }
++
++ if (matchLength > bestLength) {
++ if (matchLength > matchEndIdx - matchIndex)
++ matchEndIdx = matchIndex + (U32)matchLength;
++ bestLength = matchLength;
++ matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex;
++ matches[mnum].len = (U32)matchLength;
++ mnum++;
++ if (matchLength > ZSTD_OPT_NUM)
++ break;
++ if (ip + matchLength == iLimit) /* equal : no way to know if inf or sup */
++ break; /* drop, to guarantee consistency (miss a little bit of compression) */
++ }
++
++ if (match[matchLength] < ip[matchLength]) {
++ /* match is smaller than curr */
++ *smallerPtr = matchIndex; /* update smaller idx */
++ commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
++ if (matchIndex <= btLow) {
++ smallerPtr = &dummy32;
++ break;
++ } /* beyond tree size, stop the search */
++ smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */
++ matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */
++ } else {
++ /* match is larger than curr */
++ *largerPtr = matchIndex;
++ commonLengthLarger = matchLength;
++ if (matchIndex <= btLow) {
++ largerPtr = &dummy32;
++ break;
++ } /* beyond tree size, stop the search */
++ largerPtr = nextPtr;
++ matchIndex = nextPtr[0];
++ }
++ }
++
++ *smallerPtr = *largerPtr = 0;
++
++update:
++ zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1;
++ return mnum;
++}
++
++/** Tree updater, providing best match */
++static U32 ZSTD_BtGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, ZSTD_match_t *matches,
++ const U32 minMatchLen)
++{
++ if (ip < zc->base + zc->nextToUpdate)
++ return 0; /* skipped area */
++ ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
++ return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 0, matches, minMatchLen);
++}
++
++static U32 ZSTD_BtGetAllMatches_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */
++ const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch,
++ ZSTD_match_t *matches, const U32 minMatchLen)
++{
++ switch (matchLengthSearch) {
++ case 3: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
++ default:
++ case 4: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
++ case 5: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
++ case 7:
++ case 6: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
++ }
++}
++
++/** Tree updater, providing best match */
++static U32 ZSTD_BtGetAllMatches_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls,
++ ZSTD_match_t *matches, const U32 minMatchLen)
++{
++ if (ip < zc->base + zc->nextToUpdate)
++ return 0; /* skipped area */
++ ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
++ return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 1, matches, minMatchLen);
++}
++
++static U32 ZSTD_BtGetAllMatches_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */
++ const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch,
++ ZSTD_match_t *matches, const U32 minMatchLen)
++{
++ switch (matchLengthSearch) {
++ case 3: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
++ default:
++ case 4: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
++ case 5: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
++ case 7:
++ case 6: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
++ }
++}
++
++/*-*******************************
++* Optimal parser
++*********************************/
++FORCE_INLINE
++void ZSTD_compressBlock_opt_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra)
++{
++ seqStore_t *seqStorePtr = &(ctx->seqStore);
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - 8;
++ const BYTE *const base = ctx->base;
++ const BYTE *const prefixStart = base + ctx->dictLimit;
++
++ const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
++ const U32 sufficient_len = ctx->params.cParams.targetLength;
++ const U32 mls = ctx->params.cParams.searchLength;
++ const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
++
++ ZSTD_optimal_t *opt = seqStorePtr->priceTable;
++ ZSTD_match_t *matches = seqStorePtr->matchTable;
++ const BYTE *inr;
++ U32 offset, rep[ZSTD_REP_NUM];
++
++ /* init */
++ ctx->nextToUpdate3 = ctx->nextToUpdate;
++ ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize);
++ ip += (ip == prefixStart);
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ rep[i] = ctx->rep[i];
++ }
++
++ /* Match Loop */
++ while (ip < ilimit) {
++ U32 cur, match_num, last_pos, litlen, price;
++ U32 u, mlen, best_mlen, best_off, litLength;
++ memset(opt, 0, sizeof(ZSTD_optimal_t));
++ last_pos = 0;
++ litlen = (U32)(ip - anchor);
++
++ /* check repCode */
++ {
++ U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor);
++ for (i = (ip == anchor); i < last_i; i++) {
++ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
++ if ((repCur > 0) && (repCur < (S32)(ip - prefixStart)) &&
++ (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) {
++ mlen = (U32)ZSTD_count(ip + minMatch, ip + minMatch - repCur, iend) + minMatch;
++ if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
++ best_mlen = mlen;
++ best_off = i;
++ cur = 0;
++ last_pos = 1;
++ goto _storeSequence;
++ }
++ best_off = i - (ip == anchor);
++ do {
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
++ if (mlen > last_pos || price < opt[mlen].price)
++ SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
++ mlen--;
++ } while (mlen >= minMatch);
++ }
++ }
++ }
++
++ match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, ip, iend, maxSearches, mls, matches, minMatch);
++
++ if (!last_pos && !match_num) {
++ ip++;
++ continue;
++ }
++
++ if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
++ best_mlen = matches[match_num - 1].len;
++ best_off = matches[match_num - 1].off;
++ cur = 0;
++ last_pos = 1;
++ goto _storeSequence;
++ }
++
++ /* set prices using matches at position = 0 */
++ best_mlen = (last_pos) ? last_pos : minMatch;
++ for (u = 0; u < match_num; u++) {
++ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
++ best_mlen = matches[u].len;
++ while (mlen <= best_mlen) {
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
++ if (mlen > last_pos || price < opt[mlen].price)
++ SET_PRICE(mlen, mlen, matches[u].off, litlen, price); /* note : macro modifies last_pos */
++ mlen++;
++ }
++ }
++
++ if (last_pos < minMatch) {
++ ip++;
++ continue;
++ }
++
++ /* initialize opt[0] */
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ opt[0].rep[i] = rep[i];
++ }
++ opt[0].mlen = 1;
++ opt[0].litlen = litlen;
++
++ /* check further positions */
++ for (cur = 1; cur <= last_pos; cur++) {
++ inr = ip + cur;
++
++ if (opt[cur - 1].mlen == 1) {
++ litlen = opt[cur - 1].litlen + 1;
++ if (cur > litlen) {
++ price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen);
++ } else
++ price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
++ } else {
++ litlen = 1;
++ price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1);
++ }
++
++ if (cur > last_pos || price <= opt[cur].price)
++ SET_PRICE(cur, 1, 0, litlen, price);
++
++ if (cur == last_pos)
++ break;
++
++ if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */
++ continue;
++
++ mlen = opt[cur].mlen;
++ if (opt[cur].off > ZSTD_REP_MOVE_OPT) {
++ opt[cur].rep[2] = opt[cur - mlen].rep[1];
++ opt[cur].rep[1] = opt[cur - mlen].rep[0];
++ opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
++ } else {
++ opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2];
++ opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1];
++ opt[cur].rep[0] =
++ ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]);
++ }
++
++ best_mlen = minMatch;
++ {
++ U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
++ for (i = (opt[cur].mlen != 1); i < last_i; i++) { /* check rep */
++ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
++ if ((repCur > 0) && (repCur < (S32)(inr - prefixStart)) &&
++ (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) {
++ mlen = (U32)ZSTD_count(inr + minMatch, inr + minMatch - repCur, iend) + minMatch;
++
++ if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
++ best_mlen = mlen;
++ best_off = i;
++ last_pos = cur + 1;
++ goto _storeSequence;
++ }
++
++ best_off = i - (opt[cur].mlen != 1);
++ if (mlen > best_mlen)
++ best_mlen = mlen;
++
++ do {
++ if (opt[cur].mlen == 1) {
++ litlen = opt[cur].litlen;
++ if (cur > litlen) {
++ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen,
++ best_off, mlen - MINMATCH, ultra);
++ } else
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
++ } else {
++ litlen = 0;
++ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
++ }
++
++ if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
++ SET_PRICE(cur + mlen, mlen, i, litlen, price);
++ mlen--;
++ } while (mlen >= minMatch);
++ }
++ }
++ }
++
++ match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, inr, iend, maxSearches, mls, matches, best_mlen);
++
++ if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
++ best_mlen = matches[match_num - 1].len;
++ best_off = matches[match_num - 1].off;
++ last_pos = cur + 1;
++ goto _storeSequence;
++ }
++
++ /* set prices using matches at position = cur */
++ for (u = 0; u < match_num; u++) {
++ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
++ best_mlen = matches[u].len;
++
++ while (mlen <= best_mlen) {
++ if (opt[cur].mlen == 1) {
++ litlen = opt[cur].litlen;
++ if (cur > litlen)
++ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen,
++ matches[u].off - 1, mlen - MINMATCH, ultra);
++ else
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
++ } else {
++ litlen = 0;
++ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra);
++ }
++
++ if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
++ SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
++
++ mlen++;
++ }
++ }
++ }
++
++ best_mlen = opt[last_pos].mlen;
++ best_off = opt[last_pos].off;
++ cur = last_pos - best_mlen;
++
++ /* store sequence */
++_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
++ opt[0].mlen = 1;
++
++ while (1) {
++ mlen = opt[cur].mlen;
++ offset = opt[cur].off;
++ opt[cur].mlen = best_mlen;
++ opt[cur].off = best_off;
++ best_mlen = mlen;
++ best_off = offset;
++ if (mlen > cur)
++ break;
++ cur -= mlen;
++ }
++
++ for (u = 0; u <= last_pos;) {
++ u += opt[u].mlen;
++ }
++
++ for (cur = 0; cur < last_pos;) {
++ mlen = opt[cur].mlen;
++ if (mlen == 1) {
++ ip++;
++ cur++;
++ continue;
++ }
++ offset = opt[cur].off;
++ cur += mlen;
++ litLength = (U32)(ip - anchor);
++
++ if (offset > ZSTD_REP_MOVE_OPT) {
++ rep[2] = rep[1];
++ rep[1] = rep[0];
++ rep[0] = offset - ZSTD_REP_MOVE_OPT;
++ offset--;
++ } else {
++ if (offset != 0) {
++ best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
++ if (offset != 1)
++ rep[2] = rep[1];
++ rep[1] = rep[0];
++ rep[0] = best_off;
++ }
++ if (litLength == 0)
++ offset--;
++ }
++
++ ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
++ ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
++ anchor = ip = ip + mlen;
++ }
++ } /* for (cur=0; cur < last_pos; ) */
++
++ /* Save reps for next block */
++ {
++ int i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ ctx->repToConfirm[i] = rep[i];
++ }
++
++ /* Last Literals */
++ {
++ size_t const lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++FORCE_INLINE
++void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra)
++{
++ seqStore_t *seqStorePtr = &(ctx->seqStore);
++ const BYTE *const istart = (const BYTE *)src;
++ const BYTE *ip = istart;
++ const BYTE *anchor = istart;
++ const BYTE *const iend = istart + srcSize;
++ const BYTE *const ilimit = iend - 8;
++ const BYTE *const base = ctx->base;
++ const U32 lowestIndex = ctx->lowLimit;
++ const U32 dictLimit = ctx->dictLimit;
++ const BYTE *const prefixStart = base + dictLimit;
++ const BYTE *const dictBase = ctx->dictBase;
++ const BYTE *const dictEnd = dictBase + dictLimit;
++
++ const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
++ const U32 sufficient_len = ctx->params.cParams.targetLength;
++ const U32 mls = ctx->params.cParams.searchLength;
++ const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
++
++ ZSTD_optimal_t *opt = seqStorePtr->priceTable;
++ ZSTD_match_t *matches = seqStorePtr->matchTable;
++ const BYTE *inr;
++
++ /* init */
++ U32 offset, rep[ZSTD_REP_NUM];
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ rep[i] = ctx->rep[i];
++ }
++
++ ctx->nextToUpdate3 = ctx->nextToUpdate;
++ ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize);
++ ip += (ip == prefixStart);
++
++ /* Match Loop */
++ while (ip < ilimit) {
++ U32 cur, match_num, last_pos, litlen, price;
++ U32 u, mlen, best_mlen, best_off, litLength;
++ U32 curr = (U32)(ip - base);
++ memset(opt, 0, sizeof(ZSTD_optimal_t));
++ last_pos = 0;
++ opt[0].litlen = (U32)(ip - anchor);
++
++ /* check repCode */
++ {
++ U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor);
++ for (i = (ip == anchor); i < last_i; i++) {
++ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
++ const U32 repIndex = (U32)(curr - repCur);
++ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *const repMatch = repBase + repIndex;
++ if ((repCur > 0 && repCur <= (S32)curr) &&
++ (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
++ && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) {
++ /* repcode detected we should take it */
++ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
++ mlen = (U32)ZSTD_count_2segments(ip + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch;
++
++ if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
++ best_mlen = mlen;
++ best_off = i;
++ cur = 0;
++ last_pos = 1;
++ goto _storeSequence;
++ }
++
++ best_off = i - (ip == anchor);
++ litlen = opt[0].litlen;
++ do {
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
++ if (mlen > last_pos || price < opt[mlen].price)
++ SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
++ mlen--;
++ } while (mlen >= minMatch);
++ }
++ }
++ }
++
++ match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, ip, iend, maxSearches, mls, matches, minMatch); /* first search (depth 0) */
++
++ if (!last_pos && !match_num) {
++ ip++;
++ continue;
++ }
++
++ {
++ U32 i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ opt[0].rep[i] = rep[i];
++ }
++ opt[0].mlen = 1;
++
++ if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
++ best_mlen = matches[match_num - 1].len;
++ best_off = matches[match_num - 1].off;
++ cur = 0;
++ last_pos = 1;
++ goto _storeSequence;
++ }
++
++ best_mlen = (last_pos) ? last_pos : minMatch;
++
++ /* set prices using matches at position = 0 */
++ for (u = 0; u < match_num; u++) {
++ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
++ best_mlen = matches[u].len;
++ litlen = opt[0].litlen;
++ while (mlen <= best_mlen) {
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
++ if (mlen > last_pos || price < opt[mlen].price)
++ SET_PRICE(mlen, mlen, matches[u].off, litlen, price);
++ mlen++;
++ }
++ }
++
++ if (last_pos < minMatch) {
++ ip++;
++ continue;
++ }
++
++ /* check further positions */
++ for (cur = 1; cur <= last_pos; cur++) {
++ inr = ip + cur;
++
++ if (opt[cur - 1].mlen == 1) {
++ litlen = opt[cur - 1].litlen + 1;
++ if (cur > litlen) {
++ price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen);
++ } else
++ price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
++ } else {
++ litlen = 1;
++ price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1);
++ }
++
++ if (cur > last_pos || price <= opt[cur].price)
++ SET_PRICE(cur, 1, 0, litlen, price);
++
++ if (cur == last_pos)
++ break;
++
++ if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */
++ continue;
++
++ mlen = opt[cur].mlen;
++ if (opt[cur].off > ZSTD_REP_MOVE_OPT) {
++ opt[cur].rep[2] = opt[cur - mlen].rep[1];
++ opt[cur].rep[1] = opt[cur - mlen].rep[0];
++ opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
++ } else {
++ opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2];
++ opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1];
++ opt[cur].rep[0] =
++ ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]);
++ }
++
++ best_mlen = minMatch;
++ {
++ U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
++ for (i = (mlen != 1); i < last_i; i++) {
++ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
++ const U32 repIndex = (U32)(curr + cur - repCur);
++ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
++ const BYTE *const repMatch = repBase + repIndex;
++ if ((repCur > 0 && repCur <= (S32)(curr + cur)) &&
++ (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
++ && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) {
++ /* repcode detected */
++ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
++ mlen = (U32)ZSTD_count_2segments(inr + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch;
++
++ if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
++ best_mlen = mlen;
++ best_off = i;
++ last_pos = cur + 1;
++ goto _storeSequence;
++ }
++
++ best_off = i - (opt[cur].mlen != 1);
++ if (mlen > best_mlen)
++ best_mlen = mlen;
++
++ do {
++ if (opt[cur].mlen == 1) {
++ litlen = opt[cur].litlen;
++ if (cur > litlen) {
++ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen,
++ best_off, mlen - MINMATCH, ultra);
++ } else
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
++ } else {
++ litlen = 0;
++ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
++ }
++
++ if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
++ SET_PRICE(cur + mlen, mlen, i, litlen, price);
++ mlen--;
++ } while (mlen >= minMatch);
++ }
++ }
++ }
++
++ match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, inr, iend, maxSearches, mls, matches, minMatch);
++
++ if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
++ best_mlen = matches[match_num - 1].len;
++ best_off = matches[match_num - 1].off;
++ last_pos = cur + 1;
++ goto _storeSequence;
++ }
++
++ /* set prices using matches at position = cur */
++ for (u = 0; u < match_num; u++) {
++ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
++ best_mlen = matches[u].len;
++
++ while (mlen <= best_mlen) {
++ if (opt[cur].mlen == 1) {
++ litlen = opt[cur].litlen;
++ if (cur > litlen)
++ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen,
++ matches[u].off - 1, mlen - MINMATCH, ultra);
++ else
++ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
++ } else {
++ litlen = 0;
++ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra);
++ }
++
++ if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
++ SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
++
++ mlen++;
++ }
++ }
++ } /* for (cur = 1; cur <= last_pos; cur++) */
++
++ best_mlen = opt[last_pos].mlen;
++ best_off = opt[last_pos].off;
++ cur = last_pos - best_mlen;
++
++ /* store sequence */
++_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
++ opt[0].mlen = 1;
++
++ while (1) {
++ mlen = opt[cur].mlen;
++ offset = opt[cur].off;
++ opt[cur].mlen = best_mlen;
++ opt[cur].off = best_off;
++ best_mlen = mlen;
++ best_off = offset;
++ if (mlen > cur)
++ break;
++ cur -= mlen;
++ }
++
++ for (u = 0; u <= last_pos;) {
++ u += opt[u].mlen;
++ }
++
++ for (cur = 0; cur < last_pos;) {
++ mlen = opt[cur].mlen;
++ if (mlen == 1) {
++ ip++;
++ cur++;
++ continue;
++ }
++ offset = opt[cur].off;
++ cur += mlen;
++ litLength = (U32)(ip - anchor);
++
++ if (offset > ZSTD_REP_MOVE_OPT) {
++ rep[2] = rep[1];
++ rep[1] = rep[0];
++ rep[0] = offset - ZSTD_REP_MOVE_OPT;
++ offset--;
++ } else {
++ if (offset != 0) {
++ best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
++ if (offset != 1)
++ rep[2] = rep[1];
++ rep[1] = rep[0];
++ rep[0] = best_off;
++ }
++
++ if (litLength == 0)
++ offset--;
++ }
++
++ ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
++ ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
++ anchor = ip = ip + mlen;
++ }
++ } /* for (cur=0; cur < last_pos; ) */
++
++ /* Save reps for next block */
++ {
++ int i;
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ ctx->repToConfirm[i] = rep[i];
++ }
++
++ /* Last Literals */
++ {
++ size_t lastLLSize = iend - anchor;
++ memcpy(seqStorePtr->lit, anchor, lastLLSize);
++ seqStorePtr->lit += lastLLSize;
++ }
++}
++
++#endif /* ZSTD_OPT_H_91842398743 */
+--
+2.9.5
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 14:23:09 +0000