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-rw-r--r--lib/lz4/Makefile6
-rw-r--r--lib/lz4/lz4_compress.c940
-rw-r--r--lib/lz4/lz4_decompress.c720
-rw-r--r--lib/lz4/lz4defs.h247
-rw-r--r--lib/lz4/lz4hc_compress.c768
5 files changed, 2681 insertions, 0 deletions
diff --git a/lib/lz4/Makefile b/lib/lz4/Makefile
new file mode 100644
index 000000000..5b42242af
--- /dev/null
+++ b/lib/lz4/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+ccflags-y += -O3
+
+obj-$(CONFIG_LZ4_COMPRESS) += lz4_compress.o
+obj-$(CONFIG_LZ4HC_COMPRESS) += lz4hc_compress.o
+obj-$(CONFIG_LZ4_DECOMPRESS) += lz4_decompress.o
diff --git a/lib/lz4/lz4_compress.c b/lib/lz4/lz4_compress.c
new file mode 100644
index 000000000..90bb67994
--- /dev/null
+++ b/lib/lz4/lz4_compress.c
@@ -0,0 +1,940 @@
+/*
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011 - 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.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
+ *
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
+ */
+
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <asm/unaligned.h>
+
+static const int LZ4_minLength = (MFLIMIT + 1);
+static const int LZ4_64Klimit = ((64 * KB) + (MFLIMIT - 1));
+
+/*-******************************
+ * Compression functions
+ ********************************/
+static FORCE_INLINE U32 LZ4_hash4(
+ U32 sequence,
+ tableType_t const tableType)
+{
+ if (tableType == byU16)
+ return ((sequence * 2654435761U)
+ >> ((MINMATCH * 8) - (LZ4_HASHLOG + 1)));
+ else
+ return ((sequence * 2654435761U)
+ >> ((MINMATCH * 8) - LZ4_HASHLOG));
+}
+
+static FORCE_INLINE U32 LZ4_hash5(
+ U64 sequence,
+ tableType_t const tableType)
+{
+ const U32 hashLog = (tableType == byU16)
+ ? LZ4_HASHLOG + 1
+ : LZ4_HASHLOG;
+
+#if LZ4_LITTLE_ENDIAN
+ static const U64 prime5bytes = 889523592379ULL;
+
+ return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
+#else
+ static const U64 prime8bytes = 11400714785074694791ULL;
+
+ return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
+#endif
+}
+
+static FORCE_INLINE U32 LZ4_hashPosition(
+ const void *p,
+ tableType_t const tableType)
+{
+#if LZ4_ARCH64
+ if (tableType == byU32)
+ return LZ4_hash5(LZ4_read_ARCH(p), tableType);
+#endif
+
+ return LZ4_hash4(LZ4_read32(p), tableType);
+}
+
+static void LZ4_putPositionOnHash(
+ const BYTE *p,
+ U32 h,
+ void *tableBase,
+ tableType_t const tableType,
+ const BYTE *srcBase)
+{
+ switch (tableType) {
+ case byPtr:
+ {
+ const BYTE **hashTable = (const BYTE **)tableBase;
+
+ hashTable[h] = p;
+ return;
+ }
+ case byU32:
+ {
+ U32 *hashTable = (U32 *) tableBase;
+
+ hashTable[h] = (U32)(p - srcBase);
+ return;
+ }
+ case byU16:
+ {
+ U16 *hashTable = (U16 *) tableBase;
+
+ hashTable[h] = (U16)(p - srcBase);
+ return;
+ }
+ }
+}
+
+static FORCE_INLINE void LZ4_putPosition(
+ const BYTE *p,
+ void *tableBase,
+ tableType_t tableType,
+ const BYTE *srcBase)
+{
+ U32 const h = LZ4_hashPosition(p, tableType);
+
+ LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
+}
+
+static const BYTE *LZ4_getPositionOnHash(
+ U32 h,
+ void *tableBase,
+ tableType_t tableType,
+ const BYTE *srcBase)
+{
+ if (tableType == byPtr) {
+ const BYTE **hashTable = (const BYTE **) tableBase;
+
+ return hashTable[h];
+ }
+
+ if (tableType == byU32) {
+ const U32 * const hashTable = (U32 *) tableBase;
+
+ return hashTable[h] + srcBase;
+ }
+
+ {
+ /* default, to ensure a return */
+ const U16 * const hashTable = (U16 *) tableBase;
+
+ return hashTable[h] + srcBase;
+ }
+}
+
+static FORCE_INLINE const BYTE *LZ4_getPosition(
+ const BYTE *p,
+ void *tableBase,
+ tableType_t tableType,
+ const BYTE *srcBase)
+{
+ U32 const h = LZ4_hashPosition(p, tableType);
+
+ return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
+}
+
+
+/*
+ * LZ4_compress_generic() :
+ * inlined, to ensure branches are decided at compilation time
+ */
+static FORCE_INLINE int LZ4_compress_generic(
+ LZ4_stream_t_internal * const dictPtr,
+ const char * const source,
+ char * const dest,
+ const int inputSize,
+ const int maxOutputSize,
+ const limitedOutput_directive outputLimited,
+ const tableType_t tableType,
+ const dict_directive dict,
+ const dictIssue_directive dictIssue,
+ const U32 acceleration)
+{
+ const BYTE *ip = (const BYTE *) source;
+ const BYTE *base;
+ const BYTE *lowLimit;
+ const BYTE * const lowRefLimit = ip - dictPtr->dictSize;
+ const BYTE * const dictionary = dictPtr->dictionary;
+ const BYTE * const dictEnd = dictionary + dictPtr->dictSize;
+ const size_t dictDelta = dictEnd - (const BYTE *)source;
+ const BYTE *anchor = (const BYTE *) source;
+ const BYTE * const iend = ip + inputSize;
+ const BYTE * const mflimit = iend - MFLIMIT;
+ const BYTE * const matchlimit = iend - LASTLITERALS;
+
+ BYTE *op = (BYTE *) dest;
+ BYTE * const olimit = op + maxOutputSize;
+
+ U32 forwardH;
+ size_t refDelta = 0;
+
+ /* Init conditions */
+ if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) {
+ /* Unsupported inputSize, too large (or negative) */
+ return 0;
+ }
+
+ switch (dict) {
+ case noDict:
+ default:
+ base = (const BYTE *)source;
+ lowLimit = (const BYTE *)source;
+ break;
+ case withPrefix64k:
+ base = (const BYTE *)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE *)source - dictPtr->dictSize;
+ break;
+ case usingExtDict:
+ base = (const BYTE *)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE *)source;
+ break;
+ }
+
+ if ((tableType == byU16)
+ && (inputSize >= LZ4_64Klimit)) {
+ /* Size too large (not within 64K limit) */
+ return 0;
+ }
+
+ if (inputSize < LZ4_minLength) {
+ /* Input too small, no compression (all literals) */
+ goto _last_literals;
+ }
+
+ /* First Byte */
+ LZ4_putPosition(ip, dictPtr->hashTable, tableType, base);
+ ip++;
+ forwardH = LZ4_hashPosition(ip, tableType);
+
+ /* Main Loop */
+ for ( ; ; ) {
+ const BYTE *match;
+ BYTE *token;
+
+ /* Find a match */
+ {
+ const BYTE *forwardIp = ip;
+ unsigned int step = 1;
+ unsigned int searchMatchNb = acceleration << LZ4_SKIPTRIGGER;
+
+ do {
+ U32 const h = forwardH;
+
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_SKIPTRIGGER);
+
+ if (unlikely(forwardIp > mflimit))
+ goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h,
+ dictPtr->hashTable,
+ tableType, base);
+
+ if (dict == usingExtDict) {
+ if (match < (const BYTE *)source) {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ } else {
+ refDelta = 0;
+ lowLimit = (const BYTE *)source;
+ } }
+
+ forwardH = LZ4_hashPosition(forwardIp,
+ tableType);
+
+ LZ4_putPositionOnHash(ip, h, dictPtr->hashTable,
+ tableType, base);
+ } while (((dictIssue == dictSmall)
+ ? (match < lowRefLimit)
+ : 0)
+ || ((tableType == byU16)
+ ? 0
+ : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match + refDelta)
+ != LZ4_read32(ip)));
+ }
+
+ /* Catch up */
+ while (((ip > anchor) & (match + refDelta > lowLimit))
+ && (unlikely(ip[-1] == match[refDelta - 1]))) {
+ ip--;
+ match--;
+ }
+
+ /* Encode Literals */
+ {
+ unsigned const int litLength = (unsigned int)(ip - anchor);
+
+ token = op++;
+
+ if ((outputLimited) &&
+ /* Check output buffer overflow */
+ (unlikely(op + litLength +
+ (2 + 1 + LASTLITERALS) +
+ (litLength / 255) > olimit)))
+ return 0;
+
+ if (litLength >= RUN_MASK) {
+ int len = (int)litLength - RUN_MASK;
+
+ *token = (RUN_MASK << ML_BITS);
+
+ for (; len >= 255; len -= 255)
+ *op++ = 255;
+ *op++ = (BYTE)len;
+ } else
+ *token = (BYTE)(litLength << ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op + litLength);
+ op += litLength;
+ }
+
+_next_match:
+ /* Encode Offset */
+ LZ4_writeLE16(op, (U16)(ip - match));
+ op += 2;
+
+ /* Encode MatchLength */
+ {
+ unsigned int matchCode;
+
+ if ((dict == usingExtDict)
+ && (lowLimit == dictionary)) {
+ const BYTE *limit;
+
+ match += refDelta;
+ limit = ip + (dictEnd - match);
+
+ if (limit > matchlimit)
+ limit = matchlimit;
+
+ matchCode = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, limit);
+
+ ip += MINMATCH + matchCode;
+
+ if (ip == limit) {
+ unsigned const int more = LZ4_count(ip,
+ (const BYTE *)source,
+ matchlimit);
+
+ matchCode += more;
+ ip += more;
+ }
+ } else {
+ matchCode = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, matchlimit);
+ ip += MINMATCH + matchCode;
+ }
+
+ if (outputLimited &&
+ /* Check output buffer overflow */
+ (unlikely(op +
+ (1 + LASTLITERALS) +
+ (matchCode >> 8) > olimit)))
+ return 0;
+
+ if (matchCode >= ML_MASK) {
+ *token += ML_MASK;
+ matchCode -= ML_MASK;
+ LZ4_write32(op, 0xFFFFFFFF);
+
+ while (matchCode >= 4 * 255) {
+ op += 4;
+ LZ4_write32(op, 0xFFFFFFFF);
+ matchCode -= 4 * 255;
+ }
+
+ op += matchCode / 255;
+ *op++ = (BYTE)(matchCode % 255);
+ } else
+ *token += (BYTE)(matchCode);
+ }
+
+ anchor = ip;
+
+ /* Test end of chunk */
+ if (ip > mflimit)
+ break;
+
+ /* Fill table */
+ LZ4_putPosition(ip - 2, dictPtr->hashTable, tableType, base);
+
+ /* Test next position */
+ match = LZ4_getPosition(ip, dictPtr->hashTable,
+ tableType, base);
+
+ if (dict == usingExtDict) {
+ if (match < (const BYTE *)source) {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ } else {
+ refDelta = 0;
+ lowLimit = (const BYTE *)source;
+ }
+ }
+
+ LZ4_putPosition(ip, dictPtr->hashTable, tableType, base);
+
+ if (((dictIssue == dictSmall) ? (match >= lowRefLimit) : 1)
+ && (match + MAX_DISTANCE >= ip)
+ && (LZ4_read32(match + refDelta) == LZ4_read32(ip))) {
+ token = op++;
+ *token = 0;
+ goto _next_match;
+ }
+
+ /* Prepare next loop */
+ forwardH = LZ4_hashPosition(++ip, tableType);
+ }
+
+_last_literals:
+ /* Encode Last Literals */
+ {
+ size_t const lastRun = (size_t)(iend - anchor);
+
+ if ((outputLimited) &&
+ /* Check output buffer overflow */
+ ((op - (BYTE *)dest) + lastRun + 1 +
+ ((lastRun + 255 - RUN_MASK) / 255) > (U32)maxOutputSize))
+ return 0;
+
+ if (lastRun >= RUN_MASK) {
+ size_t accumulator = lastRun - RUN_MASK;
+ *op++ = RUN_MASK << ML_BITS;
+ for (; accumulator >= 255; accumulator -= 255)
+ *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ } else {
+ *op++ = (BYTE)(lastRun << ML_BITS);
+ }
+
+ LZ4_memcpy(op, anchor, lastRun);
+
+ op += lastRun;
+ }
+
+ /* End */
+ return (int) (((char *)op) - dest);
+}
+
+static int LZ4_compress_fast_extState(
+ void *state,
+ const char *source,
+ char *dest,
+ int inputSize,
+ int maxOutputSize,
+ int acceleration)
+{
+ LZ4_stream_t_internal *ctx = &((LZ4_stream_t *)state)->internal_donotuse;
+#if LZ4_ARCH64
+ const tableType_t tableType = byU32;
+#else
+ const tableType_t tableType = byPtr;
+#endif
+
+ LZ4_resetStream((LZ4_stream_t *)state);
+
+ if (acceleration < 1)
+ acceleration = LZ4_ACCELERATION_DEFAULT;
+
+ if (maxOutputSize >= LZ4_COMPRESSBOUND(inputSize)) {
+ if (inputSize < LZ4_64Klimit)
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize, 0,
+ noLimit, byU16, noDict,
+ noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize, 0,
+ noLimit, tableType, noDict,
+ noDictIssue, acceleration);
+ } else {
+ if (inputSize < LZ4_64Klimit)
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize,
+ maxOutputSize, limitedOutput, byU16, noDict,
+ noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize,
+ maxOutputSize, limitedOutput, tableType, noDict,
+ noDictIssue, acceleration);
+ }
+}
+
+int LZ4_compress_fast(const char *source, char *dest, int inputSize,
+ int maxOutputSize, int acceleration, void *wrkmem)
+{
+ return LZ4_compress_fast_extState(wrkmem, source, dest, inputSize,
+ maxOutputSize, acceleration);
+}
+EXPORT_SYMBOL(LZ4_compress_fast);
+
+int LZ4_compress_default(const char *source, char *dest, int inputSize,
+ int maxOutputSize, void *wrkmem)
+{
+ return LZ4_compress_fast(source, dest, inputSize,
+ maxOutputSize, LZ4_ACCELERATION_DEFAULT, wrkmem);
+}
+EXPORT_SYMBOL(LZ4_compress_default);
+
+/*-******************************
+ * *_destSize() variant
+ ********************************/
+static int LZ4_compress_destSize_generic(
+ LZ4_stream_t_internal * const ctx,
+ const char * const src,
+ char * const dst,
+ int * const srcSizePtr,
+ const int targetDstSize,
+ const tableType_t tableType)
+{
+ const BYTE *ip = (const BYTE *) src;
+ const BYTE *base = (const BYTE *) src;
+ const BYTE *lowLimit = (const BYTE *) src;
+ const BYTE *anchor = ip;
+ const BYTE * const iend = ip + *srcSizePtr;
+ const BYTE * const mflimit = iend - MFLIMIT;
+ const BYTE * const matchlimit = iend - LASTLITERALS;
+
+ BYTE *op = (BYTE *) dst;
+ BYTE * const oend = op + targetDstSize;
+ BYTE * const oMaxLit = op + targetDstSize - 2 /* offset */
+ - 8 /* because 8 + MINMATCH == MFLIMIT */ - 1 /* token */;
+ BYTE * const oMaxMatch = op + targetDstSize
+ - (LASTLITERALS + 1 /* token */);
+ BYTE * const oMaxSeq = oMaxLit - 1 /* token */;
+
+ U32 forwardH;
+
+ /* Init conditions */
+ /* Impossible to store anything */
+ if (targetDstSize < 1)
+ return 0;
+ /* Unsupported input size, too large (or negative) */
+ if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE)
+ return 0;
+ /* Size too large (not within 64K limit) */
+ if ((tableType == byU16) && (*srcSizePtr >= LZ4_64Klimit))
+ return 0;
+ /* Input too small, no compression (all literals) */
+ if (*srcSizePtr < LZ4_minLength)
+ goto _last_literals;
+
+ /* First Byte */
+ *srcSizePtr = 0;
+ LZ4_putPosition(ip, ctx->hashTable, tableType, base);
+ ip++; forwardH = LZ4_hashPosition(ip, tableType);
+
+ /* Main Loop */
+ for ( ; ; ) {
+ const BYTE *match;
+ BYTE *token;
+
+ /* Find a match */
+ {
+ const BYTE *forwardIp = ip;
+ unsigned int step = 1;
+ unsigned int searchMatchNb = 1 << LZ4_SKIPTRIGGER;
+
+ do {
+ U32 h = forwardH;
+
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_SKIPTRIGGER);
+
+ if (unlikely(forwardIp > mflimit))
+ goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h, ctx->hashTable,
+ tableType, base);
+ forwardH = LZ4_hashPosition(forwardIp,
+ tableType);
+ LZ4_putPositionOnHash(ip, h,
+ ctx->hashTable, tableType,
+ base);
+
+ } while (((tableType == byU16)
+ ? 0
+ : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match) != LZ4_read32(ip)));
+ }
+
+ /* Catch up */
+ while ((ip > anchor)
+ && (match > lowLimit)
+ && (unlikely(ip[-1] == match[-1]))) {
+ ip--;
+ match--;
+ }
+
+ /* Encode Literal length */
+ {
+ unsigned int litLength = (unsigned int)(ip - anchor);
+
+ token = op++;
+ if (op + ((litLength + 240) / 255)
+ + litLength > oMaxLit) {
+ /* Not enough space for a last match */
+ op--;
+ goto _last_literals;
+ }
+ if (litLength >= RUN_MASK) {
+ unsigned int len = litLength - RUN_MASK;
+ *token = (RUN_MASK<<ML_BITS);
+ for (; len >= 255; len -= 255)
+ *op++ = 255;
+ *op++ = (BYTE)len;
+ } else
+ *token = (BYTE)(litLength << ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op + litLength);
+ op += litLength;
+ }
+
+_next_match:
+ /* Encode Offset */
+ LZ4_writeLE16(op, (U16)(ip - match)); op += 2;
+
+ /* Encode MatchLength */
+ {
+ size_t matchLength = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, matchlimit);
+
+ if (op + ((matchLength + 240)/255) > oMaxMatch) {
+ /* Match description too long : reduce it */
+ matchLength = (15 - 1) + (oMaxMatch - op) * 255;
+ }
+ ip += MINMATCH + matchLength;
+
+ if (matchLength >= ML_MASK) {
+ *token += ML_MASK;
+ matchLength -= ML_MASK;
+ while (matchLength >= 255) {
+ matchLength -= 255;
+ *op++ = 255;
+ }
+ *op++ = (BYTE)matchLength;
+ } else
+ *token += (BYTE)(matchLength);
+ }
+
+ anchor = ip;
+
+ /* Test end of block */
+ if (ip > mflimit)
+ break;
+ if (op > oMaxSeq)
+ break;
+
+ /* Fill table */
+ LZ4_putPosition(ip - 2, ctx->hashTable, tableType, base);
+
+ /* Test next position */
+ match = LZ4_getPosition(ip, ctx->hashTable, tableType, base);
+ LZ4_putPosition(ip, ctx->hashTable, tableType, base);
+
+ if ((match + MAX_DISTANCE >= ip)
+ && (LZ4_read32(match) == LZ4_read32(ip))) {
+ token = op++; *token = 0;
+ goto _next_match;
+ }
+
+ /* Prepare next loop */
+ forwardH = LZ4_hashPosition(++ip, tableType);
+ }
+
+_last_literals:
+ /* Encode Last Literals */
+ {
+ size_t lastRunSize = (size_t)(iend - anchor);
+
+ if (op + 1 /* token */
+ + ((lastRunSize + 240) / 255) /* litLength */
+ + lastRunSize /* literals */ > oend) {
+ /* adapt lastRunSize to fill 'dst' */
+ lastRunSize = (oend - op) - 1;
+ lastRunSize -= (lastRunSize + 240) / 255;
+ }
+ ip = anchor + lastRunSize;
+
+ if (lastRunSize >= RUN_MASK) {
+ size_t accumulator = lastRunSize - RUN_MASK;
+
+ *op++ = RUN_MASK << ML_BITS;
+ for (; accumulator >= 255; accumulator -= 255)
+ *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ } else {
+ *op++ = (BYTE)(lastRunSize<<ML_BITS);
+ }
+ LZ4_memcpy(op, anchor, lastRunSize);
+ op += lastRunSize;
+ }
+
+ /* End */
+ *srcSizePtr = (int) (((const char *)ip) - src);
+ return (int) (((char *)op) - dst);
+}
+
+static int LZ4_compress_destSize_extState(
+ LZ4_stream_t *state,
+ const char *src,
+ char *dst,
+ int *srcSizePtr,
+ int targetDstSize)
+{
+#if LZ4_ARCH64
+ const tableType_t tableType = byU32;
+#else
+ const tableType_t tableType = byPtr;
+#endif
+
+ LZ4_resetStream(state);
+
+ if (targetDstSize >= LZ4_COMPRESSBOUND(*srcSizePtr)) {
+ /* compression success is guaranteed */
+ return LZ4_compress_fast_extState(
+ state, src, dst, *srcSizePtr,
+ targetDstSize, 1);
+ } else {
+ if (*srcSizePtr < LZ4_64Klimit)
+ return LZ4_compress_destSize_generic(
+ &state->internal_donotuse,
+ src, dst, srcSizePtr,
+ targetDstSize, byU16);
+ else
+ return LZ4_compress_destSize_generic(
+ &state->internal_donotuse,
+ src, dst, srcSizePtr,
+ targetDstSize, tableType);
+ }
+}
+
+
+int LZ4_compress_destSize(
+ const char *src,
+ char *dst,
+ int *srcSizePtr,
+ int targetDstSize,
+ void *wrkmem)
+{
+ return LZ4_compress_destSize_extState(wrkmem, src, dst, srcSizePtr,
+ targetDstSize);
+}
+EXPORT_SYMBOL(LZ4_compress_destSize);
+
+/*-******************************
+ * Streaming functions
+ ********************************/
+void LZ4_resetStream(LZ4_stream_t *LZ4_stream)
+{
+ memset(LZ4_stream, 0, sizeof(LZ4_stream_t));
+}
+
+int LZ4_loadDict(LZ4_stream_t *LZ4_dict,
+ const char *dictionary, int dictSize)
+{
+ LZ4_stream_t_internal *dict = &LZ4_dict->internal_donotuse;
+ const BYTE *p = (const BYTE *)dictionary;
+ const BYTE * const dictEnd = p + dictSize;
+ const BYTE *base;
+
+ if ((dict->initCheck)
+ || (dict->currentOffset > 1 * GB)) {
+ /* Uninitialized structure, or reuse overflow */
+ LZ4_resetStream(LZ4_dict);
+ }
+
+ if (dictSize < (int)HASH_UNIT) {
+ dict->dictionary = NULL;
+ dict->dictSize = 0;
+ return 0;
+ }
+
+ if ((dictEnd - p) > 64 * KB)
+ p = dictEnd - 64 * KB;
+ dict->currentOffset += 64 * KB;
+ base = p - dict->currentOffset;
+ dict->dictionary = p;
+ dict->dictSize = (U32)(dictEnd - p);
+ dict->currentOffset += dict->dictSize;
+
+ while (p <= dictEnd - HASH_UNIT) {
+ LZ4_putPosition(p, dict->hashTable, byU32, base);
+ p += 3;
+ }
+
+ return dict->dictSize;
+}
+EXPORT_SYMBOL(LZ4_loadDict);
+
+static void LZ4_renormDictT(LZ4_stream_t_internal *LZ4_dict,
+ const BYTE *src)
+{
+ if ((LZ4_dict->currentOffset > 0x80000000) ||
+ ((uptrval)LZ4_dict->currentOffset > (uptrval)src)) {
+ /* address space overflow */
+ /* rescale hash table */
+ U32 const delta = LZ4_dict->currentOffset - 64 * KB;
+ const BYTE *dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
+ int i;
+
+ for (i = 0; i < LZ4_HASH_SIZE_U32; i++) {
+ if (LZ4_dict->hashTable[i] < delta)
+ LZ4_dict->hashTable[i] = 0;
+ else
+ LZ4_dict->hashTable[i] -= delta;
+ }
+ LZ4_dict->currentOffset = 64 * KB;
+ if (LZ4_dict->dictSize > 64 * KB)
+ LZ4_dict->dictSize = 64 * KB;
+ LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
+ }
+}
+
+int LZ4_saveDict(LZ4_stream_t *LZ4_dict, char *safeBuffer, int dictSize)
+{
+ LZ4_stream_t_internal * const dict = &LZ4_dict->internal_donotuse;
+ const BYTE * const previousDictEnd = dict->dictionary + dict->dictSize;
+
+ if ((U32)dictSize > 64 * KB) {
+ /* useless to define a dictionary > 64 * KB */
+ dictSize = 64 * KB;
+ }
+ if ((U32)dictSize > dict->dictSize)
+ dictSize = dict->dictSize;
+
+ memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
+
+ dict->dictionary = (const BYTE *)safeBuffer;
+ dict->dictSize = (U32)dictSize;
+
+ return dictSize;
+}
+EXPORT_SYMBOL(LZ4_saveDict);
+
+int LZ4_compress_fast_continue(LZ4_stream_t *LZ4_stream, const char *source,
+ char *dest, int inputSize, int maxOutputSize, int acceleration)
+{
+ LZ4_stream_t_internal *streamPtr = &LZ4_stream->internal_donotuse;
+ const BYTE * const dictEnd = streamPtr->dictionary
+ + streamPtr->dictSize;
+
+ const BYTE *smallest = (const BYTE *) source;
+
+ if (streamPtr->initCheck) {
+ /* Uninitialized structure detected */
+ return 0;
+ }
+
+ if ((streamPtr->dictSize > 0) && (smallest > dictEnd))
+ smallest = dictEnd;
+
+ LZ4_renormDictT(streamPtr, smallest);
+
+ if (acceleration < 1)
+ acceleration = LZ4_ACCELERATION_DEFAULT;
+
+ /* Check overlapping input/dictionary space */
+ {
+ const BYTE *sourceEnd = (const BYTE *) source + inputSize;
+
+ if ((sourceEnd > streamPtr->dictionary)
+ && (sourceEnd < dictEnd)) {
+ streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
+ if (streamPtr->dictSize > 64 * KB)
+ streamPtr->dictSize = 64 * KB;
+ if (streamPtr->dictSize < 4)
+ streamPtr->dictSize = 0;
+ streamPtr->dictionary = dictEnd - streamPtr->dictSize;
+ }
+ }
+
+ /* prefix mode : source data follows dictionary */
+ if (dictEnd == (const BYTE *)source) {
+ int result;
+
+ if ((streamPtr->dictSize < 64 * KB) &&
+ (streamPtr->dictSize < streamPtr->currentOffset)) {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ withPrefix64k, dictSmall, acceleration);
+ } else {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ withPrefix64k, noDictIssue, acceleration);
+ }
+ streamPtr->dictSize += (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+
+ /* external dictionary mode */
+ {
+ int result;
+
+ if ((streamPtr->dictSize < 64 * KB) &&
+ (streamPtr->dictSize < streamPtr->currentOffset)) {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ usingExtDict, dictSmall, acceleration);
+ } else {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ usingExtDict, noDictIssue, acceleration);
+ }
+ streamPtr->dictionary = (const BYTE *)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+}
+EXPORT_SYMBOL(LZ4_compress_fast_continue);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("LZ4 compressor");
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
new file mode 100644
index 000000000..59fe69a63
--- /dev/null
+++ b/lib/lz4/lz4_decompress.c
@@ -0,0 +1,720 @@
+/*
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011 - 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.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
+ *
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
+ */
+
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <asm/unaligned.h>
+
+/*-*****************************
+ * Decompression functions
+ *******************************/
+
+#define DEBUGLOG(l, ...) {} /* disabled */
+
+#ifndef assert
+#define assert(condition) ((void)0)
+#endif
+
+/*
+ * LZ4_decompress_generic() :
+ * This generic decompression function covers all use cases.
+ * It shall be instantiated several times, using different sets of directives.
+ * Note that it is important for performance that this function really get inlined,
+ * in order to remove useless branches during compilation optimization.
+ */
+static FORCE_INLINE int LZ4_decompress_generic(
+ const char * const src,
+ char * const dst,
+ int srcSize,
+ /*
+ * If endOnInput == endOnInputSize,
+ * this value is `dstCapacity`
+ */
+ int outputSize,
+ /* endOnOutputSize, endOnInputSize */
+ endCondition_directive endOnInput,
+ /* full, partial */
+ earlyEnd_directive partialDecoding,
+ /* noDict, withPrefix64k, usingExtDict */
+ dict_directive dict,
+ /* always <= dst, == dst when no prefix */
+ const BYTE * const lowPrefix,
+ /* only if dict == usingExtDict */
+ const BYTE * const dictStart,
+ /* note : = 0 if noDict */
+ const size_t dictSize
+ )
+{
+ const BYTE *ip = (const BYTE *) src;
+ const BYTE * const iend = ip + srcSize;
+
+ BYTE *op = (BYTE *) dst;
+ BYTE * const oend = op + outputSize;
+ BYTE *cpy;
+
+ const BYTE * const dictEnd = (const BYTE *)dictStart + dictSize;
+ static const unsigned int inc32table[8] = {0, 1, 2, 1, 0, 4, 4, 4};
+ static const int dec64table[8] = {0, 0, 0, -1, -4, 1, 2, 3};
+
+ const int safeDecode = (endOnInput == endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 * KB)));
+
+ /* Set up the "end" pointers for the shortcut. */
+ const BYTE *const shortiend = iend -
+ (endOnInput ? 14 : 8) /*maxLL*/ - 2 /*offset*/;
+ const BYTE *const shortoend = oend -
+ (endOnInput ? 14 : 8) /*maxLL*/ - 18 /*maxML*/;
+
+ DEBUGLOG(5, "%s (srcSize:%i, dstSize:%i)", __func__,
+ srcSize, outputSize);
+
+ /* Special cases */
+ assert(lowPrefix <= op);
+ assert(src != NULL);
+
+ /* Empty output buffer */
+ if ((endOnInput) && (unlikely(outputSize == 0)))
+ return ((srcSize == 1) && (*ip == 0)) ? 0 : -1;
+
+ if ((!endOnInput) && (unlikely(outputSize == 0)))
+ return (*ip == 0 ? 1 : -1);
+
+ if ((endOnInput) && unlikely(srcSize == 0))
+ return -1;
+
+ /* Main Loop : decode sequences */
+ while (1) {
+ size_t length;
+ const BYTE *match;
+ size_t offset;
+
+ /* get literal length */
+ unsigned int const token = *ip++;
+ length = token>>ML_BITS;
+
+ /* ip < iend before the increment */
+ assert(!endOnInput || ip <= iend);
+
+ /*
+ * A two-stage shortcut for the most common case:
+ * 1) If the literal length is 0..14, and there is enough
+ * space, enter the shortcut and copy 16 bytes on behalf
+ * of the literals (in the fast mode, only 8 bytes can be
+ * safely copied this way).
+ * 2) Further if the match length is 4..18, copy 18 bytes
+ * in a similar manner; but we ensure that there's enough
+ * space in the output for those 18 bytes earlier, upon
+ * entering the shortcut (in other words, there is a
+ * combined check for both stages).
+ *
+ * The & in the likely() below is intentionally not && so that
+ * some compilers can produce better parallelized runtime code
+ */
+ if ((endOnInput ? length != RUN_MASK : length <= 8)
+ /*
+ * strictly "less than" on input, to re-enter
+ * the loop with at least one byte
+ */
+ && likely((endOnInput ? ip < shortiend : 1) &
+ (op <= shortoend))) {
+ /* Copy the literals */
+ LZ4_memcpy(op, ip, endOnInput ? 16 : 8);
+ op += length; ip += length;
+
+ /*
+ * The second stage:
+ * prepare for match copying, decode full info.
+ * If it doesn't work out, the info won't be wasted.
+ */
+ length = token & ML_MASK; /* match length */
+ offset = LZ4_readLE16(ip);
+ ip += 2;
+ match = op - offset;
+ assert(match <= op); /* check overflow */
+
+ /* Do not deal with overlapping matches. */
+ if ((length != ML_MASK) &&
+ (offset >= 8) &&
+ (dict == withPrefix64k || match >= lowPrefix)) {
+ /* Copy the match. */
+ LZ4_memcpy(op + 0, match + 0, 8);
+ LZ4_memcpy(op + 8, match + 8, 8);
+ LZ4_memcpy(op + 16, match + 16, 2);
+ op += length + MINMATCH;
+ /* Both stages worked, load the next token. */
+ continue;
+ }
+
+ /*
+ * The second stage didn't work out, but the info
+ * is ready. Propel it right to the point of match
+ * copying.
+ */
+ goto _copy_match;
+ }
+
+ /* decode literal length */
+ if (length == RUN_MASK) {
+ unsigned int s;
+
+ if (unlikely(endOnInput ? ip >= iend - RUN_MASK : 0)) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ do {
+ s = *ip++;
+ length += s;
+ } while (likely(endOnInput
+ ? ip < iend - RUN_MASK
+ : 1) & (s == 255));
+
+ if ((safeDecode)
+ && unlikely((uptrval)(op) +
+ length < (uptrval)(op))) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ if ((safeDecode)
+ && unlikely((uptrval)(ip) +
+ length < (uptrval)(ip))) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ }
+
+ /* copy literals */
+ cpy = op + length;
+ LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH);
+
+ if (((endOnInput) && ((cpy > oend - MFLIMIT)
+ || (ip + length > iend - (2 + 1 + LASTLITERALS))))
+ || ((!endOnInput) && (cpy > oend - WILDCOPYLENGTH))) {
+ if (partialDecoding) {
+ if (cpy > oend) {
+ /*
+ * Partial decoding :
+ * stop in the middle of literal segment
+ */
+ cpy = oend;
+ length = oend - op;
+ }
+ if ((endOnInput)
+ && (ip + length > iend)) {
+ /*
+ * Error :
+ * read attempt beyond
+ * end of input buffer
+ */
+ goto _output_error;
+ }
+ } else {
+ if ((!endOnInput)
+ && (cpy != oend)) {
+ /*
+ * Error :
+ * block decoding must
+ * stop exactly there
+ */
+ goto _output_error;
+ }
+ if ((endOnInput)
+ && ((ip + length != iend)
+ || (cpy > oend))) {
+ /*
+ * Error :
+ * input must be consumed
+ */
+ goto _output_error;
+ }
+ }
+
+ /*
+ * supports overlapping memory regions; only matters
+ * for in-place decompression scenarios
+ */
+ LZ4_memmove(op, ip, length);
+ ip += length;
+ op += length;
+
+ /* Necessarily EOF when !partialDecoding.
+ * When partialDecoding, it is EOF if we've either
+ * filled the output buffer or
+ * can't proceed with reading an offset for following match.
+ */
+ if (!partialDecoding || (cpy == oend) || (ip >= (iend - 2)))
+ break;
+ } else {
+ /* may overwrite up to WILDCOPYLENGTH beyond cpy */
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length;
+ op = cpy;
+ }
+
+ /* get offset */
+ offset = LZ4_readLE16(ip);
+ ip += 2;
+ match = op - offset;
+
+ /* get matchlength */
+ length = token & ML_MASK;
+
+_copy_match:
+ if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) {
+ /* Error : offset outside buffers */
+ goto _output_error;
+ }
+
+ /* costs ~1%; silence an msan warning when offset == 0 */
+ /*
+ * note : when partialDecoding, there is no guarantee that
+ * at least 4 bytes remain available in output buffer
+ */
+ if (!partialDecoding) {
+ assert(oend > op);
+ assert(oend - op >= 4);
+
+ LZ4_write32(op, (U32)offset);
+ }
+
+ if (length == ML_MASK) {
+ unsigned int s;
+
+ do {
+ s = *ip++;
+
+ if ((endOnInput) && (ip > iend - LASTLITERALS))
+ goto _output_error;
+
+ length += s;
+ } while (s == 255);
+
+ if ((safeDecode)
+ && unlikely(
+ (uptrval)(op) + length < (uptrval)op)) {
+ /* overflow detection */
+ goto _output_error;
+ }
+ }
+
+ length += MINMATCH;
+
+ /* match starting within external dictionary */
+ if ((dict == usingExtDict) && (match < lowPrefix)) {
+ if (unlikely(op + length > oend - LASTLITERALS)) {
+ /* doesn't respect parsing restriction */
+ if (!partialDecoding)
+ goto _output_error;
+ length = min(length, (size_t)(oend - op));
+ }
+
+ if (length <= (size_t)(lowPrefix - match)) {
+ /*
+ * match fits entirely within external
+ * dictionary : just copy
+ */
+ memmove(op, dictEnd - (lowPrefix - match),
+ length);
+ op += length;
+ } else {
+ /*
+ * match stretches into both external
+ * dictionary and current block
+ */
+ size_t const copySize = (size_t)(lowPrefix - match);
+ size_t const restSize = length - copySize;
+
+ LZ4_memcpy(op, dictEnd - copySize, copySize);
+ op += copySize;
+ if (restSize > (size_t)(op - lowPrefix)) {
+ /* overlap copy */
+ BYTE * const endOfMatch = op + restSize;
+ const BYTE *copyFrom = lowPrefix;
+
+ while (op < endOfMatch)
+ *op++ = *copyFrom++;
+ } else {
+ LZ4_memcpy(op, lowPrefix, restSize);
+ op += restSize;
+ }
+ }
+ continue;
+ }
+
+ /* copy match within block */
+ cpy = op + length;
+
+ /*
+ * partialDecoding :
+ * may not respect endBlock parsing restrictions
+ */
+ assert(op <= oend);
+ if (partialDecoding &&
+ (cpy > oend - MATCH_SAFEGUARD_DISTANCE)) {
+ size_t const mlen = min(length, (size_t)(oend - op));
+ const BYTE * const matchEnd = match + mlen;
+ BYTE * const copyEnd = op + mlen;
+
+ if (matchEnd > op) {
+ /* overlap copy */
+ while (op < copyEnd)
+ *op++ = *match++;
+ } else {
+ LZ4_memcpy(op, match, mlen);
+ }
+ op = copyEnd;
+ if (op == oend)
+ break;
+ continue;
+ }
+
+ if (unlikely(offset < 8)) {
+ op[0] = match[0];
+ op[1] = match[1];
+ op[2] = match[2];
+ op[3] = match[3];
+ match += inc32table[offset];
+ LZ4_memcpy(op + 4, match, 4);
+ match -= dec64table[offset];
+ } else {
+ LZ4_copy8(op, match);
+ match += 8;
+ }
+
+ op += 8;
+
+ if (unlikely(cpy > oend - MATCH_SAFEGUARD_DISTANCE)) {
+ BYTE * const oCopyLimit = oend - (WILDCOPYLENGTH - 1);
+
+ if (cpy > oend - LASTLITERALS) {
+ /*
+ * Error : last LASTLITERALS bytes
+ * must be literals (uncompressed)
+ */
+ goto _output_error;
+ }
+
+ if (op < oCopyLimit) {
+ LZ4_wildCopy(op, match, oCopyLimit);
+ match += oCopyLimit - op;
+ op = oCopyLimit;
+ }
+ while (op < cpy)
+ *op++ = *match++;
+ } else {
+ LZ4_copy8(op, match);
+ if (length > 16)
+ LZ4_wildCopy(op + 8, match + 8, cpy);
+ }
+ op = cpy; /* wildcopy correction */
+ }
+
+ /* end of decoding */
+ if (endOnInput) {
+ /* Nb of output bytes decoded */
+ return (int) (((char *)op) - dst);
+ } else {
+ /* Nb of input bytes read */
+ return (int) (((const char *)ip) - src);
+ }
+
+ /* Overflow error detected */
+_output_error:
+ return (int) (-(((const char *)ip) - src)) - 1;
+}
+
+int LZ4_decompress_safe(const char *source, char *dest,
+ int compressedSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxDecompressedSize,
+ endOnInputSize, decode_full_block,
+ noDict, (BYTE *)dest, NULL, 0);
+}
+
+int LZ4_decompress_safe_partial(const char *src, char *dst,
+ int compressedSize, int targetOutputSize, int dstCapacity)
+{
+ dstCapacity = min(targetOutputSize, dstCapacity);
+ return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity,
+ endOnInputSize, partial_decode,
+ noDict, (BYTE *)dst, NULL, 0);
+}
+
+int LZ4_decompress_fast(const char *source, char *dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, decode_full_block,
+ withPrefix64k,
+ (BYTE *)dest - 64 * KB, NULL, 0);
+}
+
+/* ===== Instantiate a few more decoding cases, used more than once. ===== */
+
+static int LZ4_decompress_safe_withPrefix64k(const char *source, char *dest,
+ int compressedSize, int maxOutputSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ withPrefix64k,
+ (BYTE *)dest - 64 * KB, NULL, 0);
+}
+
+static int LZ4_decompress_safe_withSmallPrefix(const char *source, char *dest,
+ int compressedSize,
+ int maxOutputSize,
+ size_t prefixSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ noDict,
+ (BYTE *)dest - prefixSize, NULL, 0);
+}
+
+static int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest,
+ (const BYTE *)dictStart, dictSize);
+}
+
+static int LZ4_decompress_fast_extDict(const char *source, char *dest,
+ int originalSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ 0, originalSize,
+ endOnOutputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest,
+ (const BYTE *)dictStart, dictSize);
+}
+
+/*
+ * The "double dictionary" mode, for use with e.g. ring buffers: the first part
+ * of the dictionary is passed as prefix, and the second via dictStart + dictSize.
+ * These routines are used only once, in LZ4_decompress_*_continue().
+ */
+static FORCE_INLINE
+int LZ4_decompress_safe_doubleDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ size_t prefixSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest - prefixSize,
+ (const BYTE *)dictStart, dictSize);
+}
+
+static FORCE_INLINE
+int LZ4_decompress_fast_doubleDict(const char *source, char *dest,
+ int originalSize, size_t prefixSize,
+ const void *dictStart, size_t dictSize)
+{
+ return LZ4_decompress_generic(source, dest,
+ 0, originalSize,
+ endOnOutputSize, decode_full_block,
+ usingExtDict, (BYTE *)dest - prefixSize,
+ (const BYTE *)dictStart, dictSize);
+}
+
+/* ===== streaming decompression functions ===== */
+
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd =
+ &LZ4_streamDecode->internal_donotuse;
+
+ lz4sd->prefixSize = (size_t) dictSize;
+ lz4sd->prefixEnd = (const BYTE *) dictionary + dictSize;
+ lz4sd->externalDict = NULL;
+ lz4sd->extDictSize = 0;
+ return 1;
+}
+
+/*
+ * *_continue() :
+ * These decoding functions allow decompression of multiple blocks
+ * in "streaming" mode.
+ * Previously decoded blocks must still be available at the memory
+ * position where they were decoded.
+ * If it's not possible, save the relevant part of
+ * decoded data into a safe buffer,
+ * and indicate where it stands using LZ4_setStreamDecode()
+ */
+int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int compressedSize, int maxOutputSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd =
+ &LZ4_streamDecode->internal_donotuse;
+ int result;
+
+ if (lz4sd->prefixSize == 0) {
+ /* The first call, no dictionary yet. */
+ assert(lz4sd->extDictSize == 0);
+ result = LZ4_decompress_safe(source, dest,
+ compressedSize, maxOutputSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE *)dest + result;
+ } else if (lz4sd->prefixEnd == (BYTE *)dest) {
+ /* They're rolling the current segment. */
+ if (lz4sd->prefixSize >= 64 * KB - 1)
+ result = LZ4_decompress_safe_withPrefix64k(source, dest,
+ compressedSize, maxOutputSize);
+ else if (lz4sd->extDictSize == 0)
+ result = LZ4_decompress_safe_withSmallPrefix(source,
+ dest, compressedSize, maxOutputSize,
+ lz4sd->prefixSize);
+ else
+ result = LZ4_decompress_safe_doubleDict(source, dest,
+ compressedSize, maxOutputSize,
+ lz4sd->prefixSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize += result;
+ lz4sd->prefixEnd += result;
+ } else {
+ /*
+ * The buffer wraps around, or they're
+ * switching to another buffer.
+ */
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_safe_forceExtDict(source, dest,
+ compressedSize, maxOutputSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE *)dest + result;
+ }
+
+ return result;
+}
+
+int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int originalSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+ int result;
+
+ if (lz4sd->prefixSize == 0) {
+ assert(lz4sd->extDictSize == 0);
+ result = LZ4_decompress_fast(source, dest, originalSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE *)dest + originalSize;
+ } else if (lz4sd->prefixEnd == (BYTE *)dest) {
+ if (lz4sd->prefixSize >= 64 * KB - 1 ||
+ lz4sd->extDictSize == 0)
+ result = LZ4_decompress_fast(source, dest,
+ originalSize);
+ else
+ result = LZ4_decompress_fast_doubleDict(source, dest,
+ originalSize, lz4sd->prefixSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize += originalSize;
+ lz4sd->prefixEnd += originalSize;
+ } else {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_fast_extDict(source, dest,
+ originalSize, lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE *)dest + originalSize;
+ }
+ return result;
+}
+
+int LZ4_decompress_safe_usingDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ const char *dictStart, int dictSize)
+{
+ if (dictSize == 0)
+ return LZ4_decompress_safe(source, dest,
+ compressedSize, maxOutputSize);
+ if (dictStart+dictSize == dest) {
+ if (dictSize >= 64 * KB - 1)
+ return LZ4_decompress_safe_withPrefix64k(source, dest,
+ compressedSize, maxOutputSize);
+ return LZ4_decompress_safe_withSmallPrefix(source, dest,
+ compressedSize, maxOutputSize, dictSize);
+ }
+ return LZ4_decompress_safe_forceExtDict(source, dest,
+ compressedSize, maxOutputSize, dictStart, dictSize);
+}
+
+int LZ4_decompress_fast_usingDict(const char *source, char *dest,
+ int originalSize,
+ const char *dictStart, int dictSize)
+{
+ if (dictSize == 0 || dictStart + dictSize == dest)
+ return LZ4_decompress_fast(source, dest, originalSize);
+
+ return LZ4_decompress_fast_extDict(source, dest, originalSize,
+ dictStart, dictSize);
+}
+
+#ifndef STATIC
+EXPORT_SYMBOL(LZ4_decompress_safe);
+EXPORT_SYMBOL(LZ4_decompress_safe_partial);
+EXPORT_SYMBOL(LZ4_decompress_fast);
+EXPORT_SYMBOL(LZ4_setStreamDecode);
+EXPORT_SYMBOL(LZ4_decompress_safe_continue);
+EXPORT_SYMBOL(LZ4_decompress_fast_continue);
+EXPORT_SYMBOL(LZ4_decompress_safe_usingDict);
+EXPORT_SYMBOL(LZ4_decompress_fast_usingDict);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("LZ4 decompressor");
+#endif
diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h
new file mode 100644
index 000000000..330aa539b
--- /dev/null
+++ b/lib/lz4/lz4defs.h
@@ -0,0 +1,247 @@
+#ifndef __LZ4DEFS_H__
+#define __LZ4DEFS_H__
+
+/*
+ * lz4defs.h -- common and architecture specific defines for the kernel usage
+
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011-2016, 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.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
+ *
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
+ */
+
+#include <asm/unaligned.h>
+
+#include <linux/bitops.h>
+#include <linux/string.h> /* memset, memcpy */
+
+#define FORCE_INLINE __always_inline
+
+/*-************************************
+ * Basic Types
+ **************************************/
+#include <linux/types.h>
+
+typedef uint8_t BYTE;
+typedef uint16_t U16;
+typedef uint32_t U32;
+typedef int32_t S32;
+typedef uint64_t U64;
+typedef uintptr_t uptrval;
+
+/*-************************************
+ * Architecture specifics
+ **************************************/
+#if defined(CONFIG_64BIT)
+#define LZ4_ARCH64 1
+#else
+#define LZ4_ARCH64 0
+#endif
+
+#if defined(__LITTLE_ENDIAN)
+#define LZ4_LITTLE_ENDIAN 1
+#else
+#define LZ4_LITTLE_ENDIAN 0
+#endif
+
+/*-************************************
+ * Constants
+ **************************************/
+#define MINMATCH 4
+
+#define WILDCOPYLENGTH 8
+#define LASTLITERALS 5
+#define MFLIMIT (WILDCOPYLENGTH + MINMATCH)
+/*
+ * ensure it's possible to write 2 x wildcopyLength
+ * without overflowing output buffer
+ */
+#define MATCH_SAFEGUARD_DISTANCE ((2 * WILDCOPYLENGTH) - MINMATCH)
+
+/* Increase this value ==> compression run slower on incompressible data */
+#define LZ4_SKIPTRIGGER 6
+
+#define HASH_UNIT sizeof(size_t)
+
+#define KB (1 << 10)
+#define MB (1 << 20)
+#define GB (1U << 30)
+
+#define MAXD_LOG 16
+#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
+#define STEPSIZE sizeof(size_t)
+
+#define ML_BITS 4
+#define ML_MASK ((1U << ML_BITS) - 1)
+#define RUN_BITS (8 - ML_BITS)
+#define RUN_MASK ((1U << RUN_BITS) - 1)
+
+/*-************************************
+ * Reading and writing into memory
+ **************************************/
+static FORCE_INLINE U16 LZ4_read16(const void *ptr)
+{
+ return get_unaligned((const U16 *)ptr);
+}
+
+static FORCE_INLINE U32 LZ4_read32(const void *ptr)
+{
+ return get_unaligned((const U32 *)ptr);
+}
+
+static FORCE_INLINE size_t LZ4_read_ARCH(const void *ptr)
+{
+ return get_unaligned((const size_t *)ptr);
+}
+
+static FORCE_INLINE void LZ4_write16(void *memPtr, U16 value)
+{
+ put_unaligned(value, (U16 *)memPtr);
+}
+
+static FORCE_INLINE void LZ4_write32(void *memPtr, U32 value)
+{
+ put_unaligned(value, (U32 *)memPtr);
+}
+
+static FORCE_INLINE U16 LZ4_readLE16(const void *memPtr)
+{
+ return get_unaligned_le16(memPtr);
+}
+
+static FORCE_INLINE void LZ4_writeLE16(void *memPtr, U16 value)
+{
+ return put_unaligned_le16(value, memPtr);
+}
+
+/*
+ * LZ4 relies on memcpy with a constant size being inlined. In freestanding
+ * environments, the compiler can't assume the implementation of memcpy() is
+ * standard compliant, so apply its specialized memcpy() inlining logic. When
+ * possible, use __builtin_memcpy() to tell the compiler to analyze memcpy()
+ * as-if it were standard compliant, so it can inline it in freestanding
+ * environments. This is needed when decompressing the Linux Kernel, for example.
+ */
+#define LZ4_memcpy(dst, src, size) __builtin_memcpy(dst, src, size)
+#define LZ4_memmove(dst, src, size) __builtin_memmove(dst, src, size)
+
+static FORCE_INLINE void LZ4_copy8(void *dst, const void *src)
+{
+#if LZ4_ARCH64
+ U64 a = get_unaligned((const U64 *)src);
+
+ put_unaligned(a, (U64 *)dst);
+#else
+ U32 a = get_unaligned((const U32 *)src);
+ U32 b = get_unaligned((const U32 *)src + 1);
+
+ put_unaligned(a, (U32 *)dst);
+ put_unaligned(b, (U32 *)dst + 1);
+#endif
+}
+
+/*
+ * customized variant of memcpy,
+ * which can overwrite up to 7 bytes beyond dstEnd
+ */
+static FORCE_INLINE void LZ4_wildCopy(void *dstPtr,
+ const void *srcPtr, void *dstEnd)
+{
+ BYTE *d = (BYTE *)dstPtr;
+ const BYTE *s = (const BYTE *)srcPtr;
+ BYTE *const e = (BYTE *)dstEnd;
+
+ do {
+ LZ4_copy8(d, s);
+ d += 8;
+ s += 8;
+ } while (d < e);
+}
+
+static FORCE_INLINE unsigned int LZ4_NbCommonBytes(register size_t val)
+{
+#if LZ4_LITTLE_ENDIAN
+ return __ffs(val) >> 3;
+#else
+ return (BITS_PER_LONG - 1 - __fls(val)) >> 3;
+#endif
+}
+
+static FORCE_INLINE unsigned int LZ4_count(
+ const BYTE *pIn,
+ const BYTE *pMatch,
+ const BYTE *pInLimit)
+{
+ const BYTE *const pStart = pIn;
+
+ while (likely(pIn < pInLimit - (STEPSIZE - 1))) {
+ size_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+
+ if (!diff) {
+ pIn += STEPSIZE;
+ pMatch += STEPSIZE;
+ continue;
+ }
+
+ pIn += LZ4_NbCommonBytes(diff);
+
+ return (unsigned int)(pIn - pStart);
+ }
+
+#if LZ4_ARCH64
+ if ((pIn < (pInLimit - 3))
+ && (LZ4_read32(pMatch) == LZ4_read32(pIn))) {
+ pIn += 4;
+ pMatch += 4;
+ }
+#endif
+
+ if ((pIn < (pInLimit - 1))
+ && (LZ4_read16(pMatch) == LZ4_read16(pIn))) {
+ pIn += 2;
+ pMatch += 2;
+ }
+
+ if ((pIn < pInLimit) && (*pMatch == *pIn))
+ pIn++;
+
+ return (unsigned int)(pIn - pStart);
+}
+
+typedef enum { noLimit = 0, limitedOutput = 1 } limitedOutput_directive;
+typedef enum { byPtr, byU32, byU16 } tableType_t;
+
+typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
+typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
+
+typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
+typedef enum { decode_full_block = 0, partial_decode = 1 } earlyEnd_directive;
+
+#define LZ4_STATIC_ASSERT(c) BUILD_BUG_ON(!(c))
+
+#endif
diff --git a/lib/lz4/lz4hc_compress.c b/lib/lz4/lz4hc_compress.c
new file mode 100644
index 000000000..e7ac8694b
--- /dev/null
+++ b/lib/lz4/lz4hc_compress.c
@@ -0,0 +1,768 @@
+/*
+ * LZ4 HC - High Compression Mode of LZ4
+ * Copyright (C) 2011-2015, 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.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
+ *
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
+ */
+
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h> /* memset */
+
+/* *************************************
+ * Local Constants and types
+ ***************************************/
+
+#define OPTIMAL_ML (int)((ML_MASK - 1) + MINMATCH)
+
+#define HASH_FUNCTION(i) (((i) * 2654435761U) \
+ >> ((MINMATCH*8) - LZ4HC_HASH_LOG))
+#define DELTANEXTU16(p) chainTable[(U16)(p)] /* faster */
+
+static U32 LZ4HC_hashPtr(const void *ptr)
+{
+ return HASH_FUNCTION(LZ4_read32(ptr));
+}
+
+/**************************************
+ * HC Compression
+ **************************************/
+static void LZ4HC_init(LZ4HC_CCtx_internal *hc4, const BYTE *start)
+{
+ memset((void *)hc4->hashTable, 0, sizeof(hc4->hashTable));
+ memset(hc4->chainTable, 0xFF, sizeof(hc4->chainTable));
+ hc4->nextToUpdate = 64 * KB;
+ hc4->base = start - 64 * KB;
+ hc4->end = start;
+ hc4->dictBase = start - 64 * KB;
+ hc4->dictLimit = 64 * KB;
+ hc4->lowLimit = 64 * KB;
+}
+
+/* Update chains up to ip (excluded) */
+static FORCE_INLINE void LZ4HC_Insert(LZ4HC_CCtx_internal *hc4,
+ const BYTE *ip)
+{
+ U16 * const chainTable = hc4->chainTable;
+ U32 * const hashTable = hc4->hashTable;
+ const BYTE * const base = hc4->base;
+ U32 const target = (U32)(ip - base);
+ U32 idx = hc4->nextToUpdate;
+
+ while (idx < target) {
+ U32 const h = LZ4HC_hashPtr(base + idx);
+ size_t delta = idx - hashTable[h];
+
+ if (delta > MAX_DISTANCE)
+ delta = MAX_DISTANCE;
+
+ DELTANEXTU16(idx) = (U16)delta;
+
+ hashTable[h] = idx;
+ idx++;
+ }
+
+ hc4->nextToUpdate = target;
+}
+
+static FORCE_INLINE int LZ4HC_InsertAndFindBestMatch(
+ LZ4HC_CCtx_internal *hc4, /* Index table will be updated */
+ const BYTE *ip,
+ const BYTE * const iLimit,
+ const BYTE **matchpos,
+ const int maxNbAttempts)
+{
+ U16 * const chainTable = hc4->chainTable;
+ U32 * const HashTable = hc4->hashTable;
+ const BYTE * const base = hc4->base;
+ const BYTE * const dictBase = hc4->dictBase;
+ const U32 dictLimit = hc4->dictLimit;
+ const U32 lowLimit = (hc4->lowLimit + 64 * KB > (U32)(ip - base))
+ ? hc4->lowLimit
+ : (U32)(ip - base) - (64 * KB - 1);
+ U32 matchIndex;
+ int nbAttempts = maxNbAttempts;
+ size_t ml = 0;
+
+ /* HC4 match finder */
+ LZ4HC_Insert(hc4, ip);
+ matchIndex = HashTable[LZ4HC_hashPtr(ip)];
+
+ while ((matchIndex >= lowLimit)
+ && (nbAttempts)) {
+ nbAttempts--;
+ if (matchIndex >= dictLimit) {
+ const BYTE * const match = base + matchIndex;
+
+ if (*(match + ml) == *(ip + ml)
+ && (LZ4_read32(match) == LZ4_read32(ip))) {
+ size_t const mlt = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, iLimit) + MINMATCH;
+
+ if (mlt > ml) {
+ ml = mlt;
+ *matchpos = match;
+ }
+ }
+ } else {
+ const BYTE * const match = dictBase + matchIndex;
+
+ if (LZ4_read32(match) == LZ4_read32(ip)) {
+ size_t mlt;
+ const BYTE *vLimit = ip
+ + (dictLimit - matchIndex);
+
+ if (vLimit > iLimit)
+ vLimit = iLimit;
+ mlt = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, vLimit) + MINMATCH;
+ if ((ip + mlt == vLimit)
+ && (vLimit < iLimit))
+ mlt += LZ4_count(ip + mlt,
+ base + dictLimit,
+ iLimit);
+ if (mlt > ml) {
+ /* virtual matchpos */
+ ml = mlt;
+ *matchpos = base + matchIndex;
+ }
+ }
+ }
+ matchIndex -= DELTANEXTU16(matchIndex);
+ }
+
+ return (int)ml;
+}
+
+static FORCE_INLINE int LZ4HC_InsertAndGetWiderMatch(
+ LZ4HC_CCtx_internal *hc4,
+ const BYTE * const ip,
+ const BYTE * const iLowLimit,
+ const BYTE * const iHighLimit,
+ int longest,
+ const BYTE **matchpos,
+ const BYTE **startpos,
+ const int maxNbAttempts)
+{
+ U16 * const chainTable = hc4->chainTable;
+ U32 * const HashTable = hc4->hashTable;
+ const BYTE * const base = hc4->base;
+ const U32 dictLimit = hc4->dictLimit;
+ const BYTE * const lowPrefixPtr = base + dictLimit;
+ const U32 lowLimit = (hc4->lowLimit + 64 * KB > (U32)(ip - base))
+ ? hc4->lowLimit
+ : (U32)(ip - base) - (64 * KB - 1);
+ const BYTE * const dictBase = hc4->dictBase;
+ U32 matchIndex;
+ int nbAttempts = maxNbAttempts;
+ int delta = (int)(ip - iLowLimit);
+
+ /* First Match */
+ LZ4HC_Insert(hc4, ip);
+ matchIndex = HashTable[LZ4HC_hashPtr(ip)];
+
+ while ((matchIndex >= lowLimit)
+ && (nbAttempts)) {
+ nbAttempts--;
+ if (matchIndex >= dictLimit) {
+ const BYTE *matchPtr = base + matchIndex;
+
+ if (*(iLowLimit + longest)
+ == *(matchPtr - delta + longest)) {
+ if (LZ4_read32(matchPtr) == LZ4_read32(ip)) {
+ int mlt = MINMATCH + LZ4_count(
+ ip + MINMATCH,
+ matchPtr + MINMATCH,
+ iHighLimit);
+ int back = 0;
+
+ while ((ip + back > iLowLimit)
+ && (matchPtr + back > lowPrefixPtr)
+ && (ip[back - 1] == matchPtr[back - 1]))
+ back--;
+
+ mlt -= back;
+
+ if (mlt > longest) {
+ longest = (int)mlt;
+ *matchpos = matchPtr + back;
+ *startpos = ip + back;
+ }
+ }
+ }
+ } else {
+ const BYTE * const matchPtr = dictBase + matchIndex;
+
+ if (LZ4_read32(matchPtr) == LZ4_read32(ip)) {
+ size_t mlt;
+ int back = 0;
+ const BYTE *vLimit = ip + (dictLimit - matchIndex);
+
+ if (vLimit > iHighLimit)
+ vLimit = iHighLimit;
+
+ mlt = LZ4_count(ip + MINMATCH,
+ matchPtr + MINMATCH, vLimit) + MINMATCH;
+
+ if ((ip + mlt == vLimit) && (vLimit < iHighLimit))
+ mlt += LZ4_count(ip + mlt, base + dictLimit,
+ iHighLimit);
+ while ((ip + back > iLowLimit)
+ && (matchIndex + back > lowLimit)
+ && (ip[back - 1] == matchPtr[back - 1]))
+ back--;
+
+ mlt -= back;
+
+ if ((int)mlt > longest) {
+ longest = (int)mlt;
+ *matchpos = base + matchIndex + back;
+ *startpos = ip + back;
+ }
+ }
+ }
+
+ matchIndex -= DELTANEXTU16(matchIndex);
+ }
+
+ return longest;
+}
+
+static FORCE_INLINE int LZ4HC_encodeSequence(
+ const BYTE **ip,
+ BYTE **op,
+ const BYTE **anchor,
+ int matchLength,
+ const BYTE * const match,
+ limitedOutput_directive limitedOutputBuffer,
+ BYTE *oend)
+{
+ int length;
+ BYTE *token;
+
+ /* Encode Literal length */
+ length = (int)(*ip - *anchor);
+ token = (*op)++;
+
+ if ((limitedOutputBuffer)
+ && ((*op + (length>>8)
+ + length + (2 + 1 + LASTLITERALS)) > oend)) {
+ /* Check output limit */
+ return 1;
+ }
+ if (length >= (int)RUN_MASK) {
+ int len;
+
+ *token = (RUN_MASK<<ML_BITS);
+ len = length - RUN_MASK;
+ for (; len > 254 ; len -= 255)
+ *(*op)++ = 255;
+ *(*op)++ = (BYTE)len;
+ } else
+ *token = (BYTE)(length<<ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(*op, *anchor, (*op) + length);
+ *op += length;
+
+ /* Encode Offset */
+ LZ4_writeLE16(*op, (U16)(*ip - match));
+ *op += 2;
+
+ /* Encode MatchLength */
+ length = (int)(matchLength - MINMATCH);
+
+ if ((limitedOutputBuffer)
+ && (*op + (length>>8)
+ + (1 + LASTLITERALS) > oend)) {
+ /* Check output limit */
+ return 1;
+ }
+
+ if (length >= (int)ML_MASK) {
+ *token += ML_MASK;
+ length -= ML_MASK;
+
+ for (; length > 509 ; length -= 510) {
+ *(*op)++ = 255;
+ *(*op)++ = 255;
+ }
+
+ if (length > 254) {
+ length -= 255;
+ *(*op)++ = 255;
+ }
+
+ *(*op)++ = (BYTE)length;
+ } else
+ *token += (BYTE)(length);
+
+ /* Prepare next loop */
+ *ip += matchLength;
+ *anchor = *ip;
+
+ return 0;
+}
+
+static int LZ4HC_compress_generic(
+ LZ4HC_CCtx_internal *const ctx,
+ const char * const source,
+ char * const dest,
+ int const inputSize,
+ int const maxOutputSize,
+ int compressionLevel,
+ limitedOutput_directive limit
+ )
+{
+ const BYTE *ip = (const BYTE *) source;
+ const BYTE *anchor = ip;
+ const BYTE * const iend = ip + inputSize;
+ const BYTE * const mflimit = iend - MFLIMIT;
+ const BYTE * const matchlimit = (iend - LASTLITERALS);
+
+ BYTE *op = (BYTE *) dest;
+ BYTE * const oend = op + maxOutputSize;
+
+ unsigned int maxNbAttempts;
+ int ml, ml2, ml3, ml0;
+ const BYTE *ref = NULL;
+ const BYTE *start2 = NULL;
+ const BYTE *ref2 = NULL;
+ const BYTE *start3 = NULL;
+ const BYTE *ref3 = NULL;
+ const BYTE *start0;
+ const BYTE *ref0;
+
+ /* init */
+ if (compressionLevel > LZ4HC_MAX_CLEVEL)
+ compressionLevel = LZ4HC_MAX_CLEVEL;
+ if (compressionLevel < 1)
+ compressionLevel = LZ4HC_DEFAULT_CLEVEL;
+ maxNbAttempts = 1 << (compressionLevel - 1);
+ ctx->end += inputSize;
+
+ ip++;
+
+ /* Main Loop */
+ while (ip < mflimit) {
+ ml = LZ4HC_InsertAndFindBestMatch(ctx, ip,
+ matchlimit, (&ref), maxNbAttempts);
+ if (!ml) {
+ ip++;
+ continue;
+ }
+
+ /* saved, in case we would skip too much */
+ start0 = ip;
+ ref0 = ref;
+ ml0 = ml;
+
+_Search2:
+ if (ip + ml < mflimit)
+ ml2 = LZ4HC_InsertAndGetWiderMatch(ctx,
+ ip + ml - 2, ip + 0,
+ matchlimit, ml, &ref2,
+ &start2, maxNbAttempts);
+ else
+ ml2 = ml;
+
+ if (ml2 == ml) {
+ /* No better match */
+ if (LZ4HC_encodeSequence(&ip, &op,
+ &anchor, ml, ref, limit, oend))
+ return 0;
+ continue;
+ }
+
+ if (start0 < ip) {
+ if (start2 < ip + ml0) {
+ /* empirical */
+ ip = start0;
+ ref = ref0;
+ ml = ml0;
+ }
+ }
+
+ /* Here, start0 == ip */
+ if ((start2 - ip) < 3) {
+ /* First Match too small : removed */
+ ml = ml2;
+ ip = start2;
+ ref = ref2;
+ goto _Search2;
+ }
+
+_Search3:
+ /*
+ * Currently we have :
+ * ml2 > ml1, and
+ * ip1 + 3 <= ip2 (usually < ip1 + ml1)
+ */
+ if ((start2 - ip) < OPTIMAL_ML) {
+ int correction;
+ int new_ml = ml;
+
+ if (new_ml > OPTIMAL_ML)
+ new_ml = OPTIMAL_ML;
+ if (ip + new_ml > start2 + ml2 - MINMATCH)
+ new_ml = (int)(start2 - ip) + ml2 - MINMATCH;
+
+ correction = new_ml - (int)(start2 - ip);
+
+ if (correction > 0) {
+ start2 += correction;
+ ref2 += correction;
+ ml2 -= correction;
+ }
+ }
+ /*
+ * Now, we have start2 = ip + new_ml,
+ * with new_ml = min(ml, OPTIMAL_ML = 18)
+ */
+
+ if (start2 + ml2 < mflimit)
+ ml3 = LZ4HC_InsertAndGetWiderMatch(ctx,
+ start2 + ml2 - 3, start2,
+ matchlimit, ml2, &ref3, &start3,
+ maxNbAttempts);
+ else
+ ml3 = ml2;
+
+ if (ml3 == ml2) {
+ /* No better match : 2 sequences to encode */
+ /* ip & ref are known; Now for ml */
+ if (start2 < ip + ml)
+ ml = (int)(start2 - ip);
+ /* Now, encode 2 sequences */
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor,
+ ml, ref, limit, oend))
+ return 0;
+ ip = start2;
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor,
+ ml2, ref2, limit, oend))
+ return 0;
+ continue;
+ }
+
+ if (start3 < ip + ml + 3) {
+ /* Not enough space for match 2 : remove it */
+ if (start3 >= (ip + ml)) {
+ /* can write Seq1 immediately
+ * ==> Seq2 is removed,
+ * so Seq3 becomes Seq1
+ */
+ if (start2 < ip + ml) {
+ int correction = (int)(ip + ml - start2);
+
+ start2 += correction;
+ ref2 += correction;
+ ml2 -= correction;
+ if (ml2 < MINMATCH) {
+ start2 = start3;
+ ref2 = ref3;
+ ml2 = ml3;
+ }
+ }
+
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor,
+ ml, ref, limit, oend))
+ return 0;
+ ip = start3;
+ ref = ref3;
+ ml = ml3;
+
+ start0 = start2;
+ ref0 = ref2;
+ ml0 = ml2;
+ goto _Search2;
+ }
+
+ start2 = start3;
+ ref2 = ref3;
+ ml2 = ml3;
+ goto _Search3;
+ }
+
+ /*
+ * OK, now we have 3 ascending matches;
+ * let's write at least the first one
+ * ip & ref are known; Now for ml
+ */
+ if (start2 < ip + ml) {
+ if ((start2 - ip) < (int)ML_MASK) {
+ int correction;
+
+ if (ml > OPTIMAL_ML)
+ ml = OPTIMAL_ML;
+ if (ip + ml > start2 + ml2 - MINMATCH)
+ ml = (int)(start2 - ip) + ml2 - MINMATCH;
+ correction = ml - (int)(start2 - ip);
+ if (correction > 0) {
+ start2 += correction;
+ ref2 += correction;
+ ml2 -= correction;
+ }
+ } else
+ ml = (int)(start2 - ip);
+ }
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml,
+ ref, limit, oend))
+ return 0;
+
+ ip = start2;
+ ref = ref2;
+ ml = ml2;
+
+ start2 = start3;
+ ref2 = ref3;
+ ml2 = ml3;
+
+ goto _Search3;
+ }
+
+ /* Encode Last Literals */
+ {
+ int lastRun = (int)(iend - anchor);
+
+ if ((limit)
+ && (((char *)op - dest) + lastRun + 1
+ + ((lastRun + 255 - RUN_MASK)/255)
+ > (U32)maxOutputSize)) {
+ /* Check output limit */
+ return 0;
+ }
+ if (lastRun >= (int)RUN_MASK) {
+ *op++ = (RUN_MASK<<ML_BITS);
+ lastRun -= RUN_MASK;
+ for (; lastRun > 254 ; lastRun -= 255)
+ *op++ = 255;
+ *op++ = (BYTE) lastRun;
+ } else
+ *op++ = (BYTE)(lastRun<<ML_BITS);
+ LZ4_memcpy(op, anchor, iend - anchor);
+ op += iend - anchor;
+ }
+
+ /* End */
+ return (int) (((char *)op) - dest);
+}
+
+static int LZ4_compress_HC_extStateHC(
+ void *state,
+ const char *src,
+ char *dst,
+ int srcSize,
+ int maxDstSize,
+ int compressionLevel)
+{
+ LZ4HC_CCtx_internal *ctx = &((LZ4_streamHC_t *)state)->internal_donotuse;
+
+ if (((size_t)(state)&(sizeof(void *) - 1)) != 0) {
+ /* Error : state is not aligned
+ * for pointers (32 or 64 bits)
+ */
+ return 0;
+ }
+
+ LZ4HC_init(ctx, (const BYTE *)src);
+
+ if (maxDstSize < LZ4_compressBound(srcSize))
+ return LZ4HC_compress_generic(ctx, src, dst,
+ srcSize, maxDstSize, compressionLevel, limitedOutput);
+ else
+ return LZ4HC_compress_generic(ctx, src, dst,
+ srcSize, maxDstSize, compressionLevel, noLimit);
+}
+
+int LZ4_compress_HC(const char *src, char *dst, int srcSize,
+ int maxDstSize, int compressionLevel, void *wrkmem)
+{
+ return LZ4_compress_HC_extStateHC(wrkmem, src, dst,
+ srcSize, maxDstSize, compressionLevel);
+}
+EXPORT_SYMBOL(LZ4_compress_HC);
+
+/**************************************
+ * Streaming Functions
+ **************************************/
+void LZ4_resetStreamHC(LZ4_streamHC_t *LZ4_streamHCPtr, int compressionLevel)
+{
+ LZ4_streamHCPtr->internal_donotuse.base = NULL;
+ LZ4_streamHCPtr->internal_donotuse.compressionLevel = (unsigned int)compressionLevel;
+}
+
+int LZ4_loadDictHC(LZ4_streamHC_t *LZ4_streamHCPtr,
+ const char *dictionary,
+ int dictSize)
+{
+ LZ4HC_CCtx_internal *ctxPtr = &LZ4_streamHCPtr->internal_donotuse;
+
+ if (dictSize > 64 * KB) {
+ dictionary += dictSize - 64 * KB;
+ dictSize = 64 * KB;
+ }
+ LZ4HC_init(ctxPtr, (const BYTE *)dictionary);
+ if (dictSize >= 4)
+ LZ4HC_Insert(ctxPtr, (const BYTE *)dictionary + (dictSize - 3));
+ ctxPtr->end = (const BYTE *)dictionary + dictSize;
+ return dictSize;
+}
+EXPORT_SYMBOL(LZ4_loadDictHC);
+
+/* compression */
+
+static void LZ4HC_setExternalDict(
+ LZ4HC_CCtx_internal *ctxPtr,
+ const BYTE *newBlock)
+{
+ if (ctxPtr->end >= ctxPtr->base + 4) {
+ /* Referencing remaining dictionary content */
+ LZ4HC_Insert(ctxPtr, ctxPtr->end - 3);
+ }
+
+ /*
+ * Only one memory segment for extDict,
+ * so any previous extDict is lost at this stage
+ */
+ ctxPtr->lowLimit = ctxPtr->dictLimit;
+ ctxPtr->dictLimit = (U32)(ctxPtr->end - ctxPtr->base);
+ ctxPtr->dictBase = ctxPtr->base;
+ ctxPtr->base = newBlock - ctxPtr->dictLimit;
+ ctxPtr->end = newBlock;
+ /* match referencing will resume from there */
+ ctxPtr->nextToUpdate = ctxPtr->dictLimit;
+}
+
+static int LZ4_compressHC_continue_generic(
+ LZ4_streamHC_t *LZ4_streamHCPtr,
+ const char *source,
+ char *dest,
+ int inputSize,
+ int maxOutputSize,
+ limitedOutput_directive limit)
+{
+ LZ4HC_CCtx_internal *ctxPtr = &LZ4_streamHCPtr->internal_donotuse;
+
+ /* auto - init if forgotten */
+ if (ctxPtr->base == NULL)
+ LZ4HC_init(ctxPtr, (const BYTE *) source);
+
+ /* Check overflow */
+ if ((size_t)(ctxPtr->end - ctxPtr->base) > 2 * GB) {
+ size_t dictSize = (size_t)(ctxPtr->end - ctxPtr->base)
+ - ctxPtr->dictLimit;
+ if (dictSize > 64 * KB)
+ dictSize = 64 * KB;
+ LZ4_loadDictHC(LZ4_streamHCPtr,
+ (const char *)(ctxPtr->end) - dictSize, (int)dictSize);
+ }
+
+ /* Check if blocks follow each other */
+ if ((const BYTE *)source != ctxPtr->end)
+ LZ4HC_setExternalDict(ctxPtr, (const BYTE *)source);
+
+ /* Check overlapping input/dictionary space */
+ {
+ const BYTE *sourceEnd = (const BYTE *) source + inputSize;
+ const BYTE * const dictBegin = ctxPtr->dictBase + ctxPtr->lowLimit;
+ const BYTE * const dictEnd = ctxPtr->dictBase + ctxPtr->dictLimit;
+
+ if ((sourceEnd > dictBegin)
+ && ((const BYTE *)source < dictEnd)) {
+ if (sourceEnd > dictEnd)
+ sourceEnd = dictEnd;
+ ctxPtr->lowLimit = (U32)(sourceEnd - ctxPtr->dictBase);
+
+ if (ctxPtr->dictLimit - ctxPtr->lowLimit < 4)
+ ctxPtr->lowLimit = ctxPtr->dictLimit;
+ }
+ }
+
+ return LZ4HC_compress_generic(ctxPtr, source, dest,
+ inputSize, maxOutputSize, ctxPtr->compressionLevel, limit);
+}
+
+int LZ4_compress_HC_continue(
+ LZ4_streamHC_t *LZ4_streamHCPtr,
+ const char *source,
+ char *dest,
+ int inputSize,
+ int maxOutputSize)
+{
+ if (maxOutputSize < LZ4_compressBound(inputSize))
+ return LZ4_compressHC_continue_generic(LZ4_streamHCPtr,
+ source, dest, inputSize, maxOutputSize, limitedOutput);
+ else
+ return LZ4_compressHC_continue_generic(LZ4_streamHCPtr,
+ source, dest, inputSize, maxOutputSize, noLimit);
+}
+EXPORT_SYMBOL(LZ4_compress_HC_continue);
+
+/* dictionary saving */
+
+int LZ4_saveDictHC(
+ LZ4_streamHC_t *LZ4_streamHCPtr,
+ char *safeBuffer,
+ int dictSize)
+{
+ LZ4HC_CCtx_internal *const streamPtr = &LZ4_streamHCPtr->internal_donotuse;
+ int const prefixSize = (int)(streamPtr->end
+ - (streamPtr->base + streamPtr->dictLimit));
+
+ if (dictSize > 64 * KB)
+ dictSize = 64 * KB;
+ if (dictSize < 4)
+ dictSize = 0;
+ if (dictSize > prefixSize)
+ dictSize = prefixSize;
+
+ memmove(safeBuffer, streamPtr->end - dictSize, dictSize);
+
+ {
+ U32 const endIndex = (U32)(streamPtr->end - streamPtr->base);
+
+ streamPtr->end = (const BYTE *)safeBuffer + dictSize;
+ streamPtr->base = streamPtr->end - endIndex;
+ streamPtr->dictLimit = endIndex - dictSize;
+ streamPtr->lowLimit = endIndex - dictSize;
+
+ if (streamPtr->nextToUpdate < streamPtr->dictLimit)
+ streamPtr->nextToUpdate = streamPtr->dictLimit;
+ }
+ return dictSize;
+}
+EXPORT_SYMBOL(LZ4_saveDictHC);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("LZ4 HC compressor");
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-08 02:44:36 +0000