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-rw-r--r--mfbt/lz4/lz4frame.c2078
1 files changed, 2078 insertions, 0 deletions
diff --git a/mfbt/lz4/lz4frame.c b/mfbt/lz4/lz4frame.c
new file mode 100644
index 0000000000..174f9ae4f2
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+++ b/mfbt/lz4/lz4frame.c
@@ -0,0 +1,2078 @@
+/*
+ * LZ4 auto-framing library
+ * 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
+ */
+
+/* LZ4F is a stand-alone API to create LZ4-compressed Frames
+ * in full conformance with specification v1.6.1 .
+ * This library rely upon memory management capabilities (malloc, free)
+ * provided either by <stdlib.h>,
+ * or redirected towards another library of user's choice
+ * (see Memory Routines below).
+ */
+
+
+/*-************************************
+* Compiler Options
+**************************************/
+#ifdef _MSC_VER /* Visual Studio */
+# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
+#endif
+
+
+/*-************************************
+* Tuning parameters
+**************************************/
+/*
+ * LZ4F_HEAPMODE :
+ * Select how default compression functions will allocate memory for their hash table,
+ * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()).
+ */
+#ifndef LZ4F_HEAPMODE
+# define LZ4F_HEAPMODE 0
+#endif
+
+
+/*-************************************
+* Library declarations
+**************************************/
+#define LZ4F_STATIC_LINKING_ONLY
+#include "lz4frame.h"
+#define LZ4_STATIC_LINKING_ONLY
+#include "lz4.h"
+#define LZ4_HC_STATIC_LINKING_ONLY
+#include "lz4hc.h"
+#define XXH_STATIC_LINKING_ONLY
+#include "xxhash.h"
+
+
+/*-************************************
+* Memory routines
+**************************************/
+/*
+ * User may redirect invocations of
+ * malloc(), calloc() and free()
+ * towards another library or solution of their choice
+ * by modifying below section.
+**/
+
+#include <string.h> /* memset, memcpy, memmove */
+#ifndef LZ4_SRC_INCLUDED /* avoid redefinition when sources are coalesced */
+# define MEM_INIT(p,v,s) memset((p),(v),(s))
+#endif
+
+#ifndef LZ4_SRC_INCLUDED /* avoid redefinition when sources are coalesced */
+# include <stdlib.h> /* malloc, calloc, free */
+# define ALLOC(s) malloc(s)
+# define ALLOC_AND_ZERO(s) calloc(1,(s))
+# define FREEMEM(p) free(p)
+#endif
+
+static void* LZ4F_calloc(size_t s, LZ4F_CustomMem cmem)
+{
+ /* custom calloc defined : use it */
+ if (cmem.customCalloc != NULL) {
+ return cmem.customCalloc(cmem.opaqueState, s);
+ }
+ /* nothing defined : use default <stdlib.h>'s calloc() */
+ if (cmem.customAlloc == NULL) {
+ return ALLOC_AND_ZERO(s);
+ }
+ /* only custom alloc defined : use it, and combine it with memset() */
+ { void* const p = cmem.customAlloc(cmem.opaqueState, s);
+ if (p != NULL) MEM_INIT(p, 0, s);
+ return p;
+} }
+
+static void* LZ4F_malloc(size_t s, LZ4F_CustomMem cmem)
+{
+ /* custom malloc defined : use it */
+ if (cmem.customAlloc != NULL) {
+ return cmem.customAlloc(cmem.opaqueState, s);
+ }
+ /* nothing defined : use default <stdlib.h>'s malloc() */
+ return ALLOC(s);
+}
+
+static void LZ4F_free(void* p, LZ4F_CustomMem cmem)
+{
+ /* custom malloc defined : use it */
+ if (cmem.customFree != NULL) {
+ cmem.customFree(cmem.opaqueState, p);
+ return;
+ }
+ /* nothing defined : use default <stdlib.h>'s free() */
+ FREEMEM(p);
+}
+
+
+/*-************************************
+* Debug
+**************************************/
+#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=1)
+# include <assert.h>
+#else
+# ifndef assert
+# define assert(condition) ((void)0)
+# endif
+#endif
+
+#define LZ4F_STATIC_ASSERT(c) { enum { LZ4F_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
+
+#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2) && !defined(DEBUGLOG)
+# include <stdio.h>
+static int g_debuglog_enable = 1;
+# define DEBUGLOG(l, ...) { \
+ if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \
+ fprintf(stderr, __FILE__ ": "); \
+ fprintf(stderr, __VA_ARGS__); \
+ fprintf(stderr, " \n"); \
+ } }
+#else
+# define DEBUGLOG(l, ...) {} /* disabled */
+#endif
+
+
+/*-************************************
+* Basic Types
+**************************************/
+#if !defined (__VMS) && (defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
+# include <stdint.h>
+ typedef uint8_t BYTE;
+ typedef uint16_t U16;
+ typedef uint32_t U32;
+ typedef int32_t S32;
+ typedef uint64_t U64;
+#else
+ typedef unsigned char BYTE;
+ typedef unsigned short U16;
+ typedef unsigned int U32;
+ typedef signed int S32;
+ typedef unsigned long long U64;
+#endif
+
+
+/* unoptimized version; solves endianness & alignment issues */
+static U32 LZ4F_readLE32 (const void* src)
+{
+ const BYTE* const srcPtr = (const BYTE*)src;
+ U32 value32 = srcPtr[0];
+ value32 += ((U32)srcPtr[1])<< 8;
+ value32 += ((U32)srcPtr[2])<<16;
+ value32 += ((U32)srcPtr[3])<<24;
+ return value32;
+}
+
+static void LZ4F_writeLE32 (void* dst, U32 value32)
+{
+ BYTE* const dstPtr = (BYTE*)dst;
+ dstPtr[0] = (BYTE)value32;
+ dstPtr[1] = (BYTE)(value32 >> 8);
+ dstPtr[2] = (BYTE)(value32 >> 16);
+ dstPtr[3] = (BYTE)(value32 >> 24);
+}
+
+static U64 LZ4F_readLE64 (const void* src)
+{
+ const BYTE* const srcPtr = (const BYTE*)src;
+ U64 value64 = srcPtr[0];
+ value64 += ((U64)srcPtr[1]<<8);
+ value64 += ((U64)srcPtr[2]<<16);
+ value64 += ((U64)srcPtr[3]<<24);
+ value64 += ((U64)srcPtr[4]<<32);
+ value64 += ((U64)srcPtr[5]<<40);
+ value64 += ((U64)srcPtr[6]<<48);
+ value64 += ((U64)srcPtr[7]<<56);
+ return value64;
+}
+
+static void LZ4F_writeLE64 (void* dst, U64 value64)
+{
+ BYTE* const dstPtr = (BYTE*)dst;
+ dstPtr[0] = (BYTE)value64;
+ dstPtr[1] = (BYTE)(value64 >> 8);
+ dstPtr[2] = (BYTE)(value64 >> 16);
+ dstPtr[3] = (BYTE)(value64 >> 24);
+ dstPtr[4] = (BYTE)(value64 >> 32);
+ dstPtr[5] = (BYTE)(value64 >> 40);
+ dstPtr[6] = (BYTE)(value64 >> 48);
+ dstPtr[7] = (BYTE)(value64 >> 56);
+}
+
+
+/*-************************************
+* Constants
+**************************************/
+#ifndef LZ4_SRC_INCLUDED /* avoid double definition */
+# define KB *(1<<10)
+# define MB *(1<<20)
+# define GB *(1<<30)
+#endif
+
+#define _1BIT 0x01
+#define _2BITS 0x03
+#define _3BITS 0x07
+#define _4BITS 0x0F
+#define _8BITS 0xFF
+
+#define LZ4F_BLOCKUNCOMPRESSED_FLAG 0x80000000U
+#define LZ4F_BLOCKSIZEID_DEFAULT LZ4F_max64KB
+
+static const size_t minFHSize = LZ4F_HEADER_SIZE_MIN; /* 7 */
+static const size_t maxFHSize = LZ4F_HEADER_SIZE_MAX; /* 19 */
+static const size_t BHSize = LZ4F_BLOCK_HEADER_SIZE; /* block header : size, and compress flag */
+static const size_t BFSize = LZ4F_BLOCK_CHECKSUM_SIZE; /* block footer : checksum (optional) */
+
+
+/*-************************************
+* Structures and local types
+**************************************/
+
+typedef enum { LZ4B_COMPRESSED, LZ4B_UNCOMPRESSED} LZ4F_blockCompression_t;
+
+typedef struct LZ4F_cctx_s
+{
+ LZ4F_CustomMem cmem;
+ LZ4F_preferences_t prefs;
+ U32 version;
+ U32 cStage;
+ const LZ4F_CDict* cdict;
+ size_t maxBlockSize;
+ size_t maxBufferSize;
+ BYTE* tmpBuff; /* internal buffer, for streaming */
+ BYTE* tmpIn; /* starting position of data compress within internal buffer (>= tmpBuff) */
+ size_t tmpInSize; /* amount of data to compress after tmpIn */
+ U64 totalInSize;
+ XXH32_state_t xxh;
+ void* lz4CtxPtr;
+ U16 lz4CtxAlloc; /* sized for: 0 = none, 1 = lz4 ctx, 2 = lz4hc ctx */
+ U16 lz4CtxState; /* in use as: 0 = none, 1 = lz4 ctx, 2 = lz4hc ctx */
+ LZ4F_blockCompression_t blockCompression;
+} LZ4F_cctx_t;
+
+
+/*-************************************
+* Error management
+**************************************/
+#define LZ4F_GENERATE_STRING(STRING) #STRING,
+static const char* LZ4F_errorStrings[] = { LZ4F_LIST_ERRORS(LZ4F_GENERATE_STRING) };
+
+
+unsigned LZ4F_isError(LZ4F_errorCode_t code)
+{
+ return (code > (LZ4F_errorCode_t)(-LZ4F_ERROR_maxCode));
+}
+
+const char* LZ4F_getErrorName(LZ4F_errorCode_t code)
+{
+ static const char* codeError = "Unspecified error code";
+ if (LZ4F_isError(code)) return LZ4F_errorStrings[-(int)(code)];
+ return codeError;
+}
+
+LZ4F_errorCodes LZ4F_getErrorCode(size_t functionResult)
+{
+ if (!LZ4F_isError(functionResult)) return LZ4F_OK_NoError;
+ return (LZ4F_errorCodes)(-(ptrdiff_t)functionResult);
+}
+
+static LZ4F_errorCode_t LZ4F_returnErrorCode(LZ4F_errorCodes code)
+{
+ /* A compilation error here means sizeof(ptrdiff_t) is not large enough */
+ LZ4F_STATIC_ASSERT(sizeof(ptrdiff_t) >= sizeof(size_t));
+ return (LZ4F_errorCode_t)-(ptrdiff_t)code;
+}
+
+#define RETURN_ERROR(e) return LZ4F_returnErrorCode(LZ4F_ERROR_ ## e)
+
+#define RETURN_ERROR_IF(c,e) if (c) RETURN_ERROR(e)
+
+#define FORWARD_IF_ERROR(r) if (LZ4F_isError(r)) return (r)
+
+unsigned LZ4F_getVersion(void) { return LZ4F_VERSION; }
+
+int LZ4F_compressionLevel_max(void) { return LZ4HC_CLEVEL_MAX; }
+
+size_t LZ4F_getBlockSize(LZ4F_blockSizeID_t blockSizeID)
+{
+ static const size_t blockSizes[4] = { 64 KB, 256 KB, 1 MB, 4 MB };
+
+ if (blockSizeID == 0) blockSizeID = LZ4F_BLOCKSIZEID_DEFAULT;
+ if (blockSizeID < LZ4F_max64KB || blockSizeID > LZ4F_max4MB)
+ RETURN_ERROR(maxBlockSize_invalid);
+ { int const blockSizeIdx = (int)blockSizeID - (int)LZ4F_max64KB;
+ return blockSizes[blockSizeIdx];
+} }
+
+/*-************************************
+* Private functions
+**************************************/
+#define MIN(a,b) ( (a) < (b) ? (a) : (b) )
+
+static BYTE LZ4F_headerChecksum (const void* header, size_t length)
+{
+ U32 const xxh = XXH32(header, length, 0);
+ return (BYTE)(xxh >> 8);
+}
+
+
+/*-************************************
+* Simple-pass compression functions
+**************************************/
+static LZ4F_blockSizeID_t LZ4F_optimalBSID(const LZ4F_blockSizeID_t requestedBSID,
+ const size_t srcSize)
+{
+ LZ4F_blockSizeID_t proposedBSID = LZ4F_max64KB;
+ size_t maxBlockSize = 64 KB;
+ while (requestedBSID > proposedBSID) {
+ if (srcSize <= maxBlockSize)
+ return proposedBSID;
+ proposedBSID = (LZ4F_blockSizeID_t)((int)proposedBSID + 1);
+ maxBlockSize <<= 2;
+ }
+ return requestedBSID;
+}
+
+/*! LZ4F_compressBound_internal() :
+ * Provides dstCapacity given a srcSize to guarantee operation success in worst case situations.
+ * prefsPtr is optional : if NULL is provided, preferences will be set to cover worst case scenario.
+ * @return is always the same for a srcSize and prefsPtr, so it can be relied upon to size reusable buffers.
+ * When srcSize==0, LZ4F_compressBound() provides an upper bound for LZ4F_flush() and LZ4F_compressEnd() operations.
+ */
+static size_t LZ4F_compressBound_internal(size_t srcSize,
+ const LZ4F_preferences_t* preferencesPtr,
+ size_t alreadyBuffered)
+{
+ LZ4F_preferences_t prefsNull = LZ4F_INIT_PREFERENCES;
+ prefsNull.frameInfo.contentChecksumFlag = LZ4F_contentChecksumEnabled; /* worst case */
+ prefsNull.frameInfo.blockChecksumFlag = LZ4F_blockChecksumEnabled; /* worst case */
+ { const LZ4F_preferences_t* const prefsPtr = (preferencesPtr==NULL) ? &prefsNull : preferencesPtr;
+ U32 const flush = prefsPtr->autoFlush | (srcSize==0);
+ LZ4F_blockSizeID_t const blockID = prefsPtr->frameInfo.blockSizeID;
+ size_t const blockSize = LZ4F_getBlockSize(blockID);
+ size_t const maxBuffered = blockSize - 1;
+ size_t const bufferedSize = MIN(alreadyBuffered, maxBuffered);
+ size_t const maxSrcSize = srcSize + bufferedSize;
+ unsigned const nbFullBlocks = (unsigned)(maxSrcSize / blockSize);
+ size_t const partialBlockSize = maxSrcSize & (blockSize-1);
+ size_t const lastBlockSize = flush ? partialBlockSize : 0;
+ unsigned const nbBlocks = nbFullBlocks + (lastBlockSize>0);
+
+ size_t const blockCRCSize = BFSize * prefsPtr->frameInfo.blockChecksumFlag;
+ size_t const frameEnd = BHSize + (prefsPtr->frameInfo.contentChecksumFlag*BFSize);
+
+ return ((BHSize + blockCRCSize) * nbBlocks) +
+ (blockSize * nbFullBlocks) + lastBlockSize + frameEnd;
+ }
+}
+
+size_t LZ4F_compressFrameBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr)
+{
+ LZ4F_preferences_t prefs;
+ size_t const headerSize = maxFHSize; /* max header size, including optional fields */
+
+ if (preferencesPtr!=NULL) prefs = *preferencesPtr;
+ else MEM_INIT(&prefs, 0, sizeof(prefs));
+ prefs.autoFlush = 1;
+
+ return headerSize + LZ4F_compressBound_internal(srcSize, &prefs, 0);;
+}
+
+
+/*! LZ4F_compressFrame_usingCDict() :
+ * Compress srcBuffer using a dictionary, in a single step.
+ * cdict can be NULL, in which case, no dictionary is used.
+ * dstBuffer MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr).
+ * The LZ4F_preferences_t structure is optional : you may provide NULL as argument,
+ * however, it's the only way to provide a dictID, so it's not recommended.
+ * @return : number of bytes written into dstBuffer,
+ * or an error code if it fails (can be tested using LZ4F_isError())
+ */
+size_t LZ4F_compressFrame_usingCDict(LZ4F_cctx* cctx,
+ void* dstBuffer, size_t dstCapacity,
+ const void* srcBuffer, size_t srcSize,
+ const LZ4F_CDict* cdict,
+ const LZ4F_preferences_t* preferencesPtr)
+{
+ LZ4F_preferences_t prefs;
+ LZ4F_compressOptions_t options;
+ BYTE* const dstStart = (BYTE*) dstBuffer;
+ BYTE* dstPtr = dstStart;
+ BYTE* const dstEnd = dstStart + dstCapacity;
+
+ if (preferencesPtr!=NULL)
+ prefs = *preferencesPtr;
+ else
+ MEM_INIT(&prefs, 0, sizeof(prefs));
+ if (prefs.frameInfo.contentSize != 0)
+ prefs.frameInfo.contentSize = (U64)srcSize; /* auto-correct content size if selected (!=0) */
+
+ prefs.frameInfo.blockSizeID = LZ4F_optimalBSID(prefs.frameInfo.blockSizeID, srcSize);
+ prefs.autoFlush = 1;
+ if (srcSize <= LZ4F_getBlockSize(prefs.frameInfo.blockSizeID))
+ prefs.frameInfo.blockMode = LZ4F_blockIndependent; /* only one block => no need for inter-block link */
+
+ MEM_INIT(&options, 0, sizeof(options));
+ options.stableSrc = 1;
+
+ RETURN_ERROR_IF(dstCapacity < LZ4F_compressFrameBound(srcSize, &prefs), dstMaxSize_tooSmall);
+
+ { size_t const headerSize = LZ4F_compressBegin_usingCDict(cctx, dstBuffer, dstCapacity, cdict, &prefs); /* write header */
+ FORWARD_IF_ERROR(headerSize);
+ dstPtr += headerSize; /* header size */ }
+
+ assert(dstEnd >= dstPtr);
+ { size_t const cSize = LZ4F_compressUpdate(cctx, dstPtr, (size_t)(dstEnd-dstPtr), srcBuffer, srcSize, &options);
+ FORWARD_IF_ERROR(cSize);
+ dstPtr += cSize; }
+
+ assert(dstEnd >= dstPtr);
+ { size_t const tailSize = LZ4F_compressEnd(cctx, dstPtr, (size_t)(dstEnd-dstPtr), &options); /* flush last block, and generate suffix */
+ FORWARD_IF_ERROR(tailSize);
+ dstPtr += tailSize; }
+
+ assert(dstEnd >= dstStart);
+ return (size_t)(dstPtr - dstStart);
+}
+
+
+/*! LZ4F_compressFrame() :
+ * Compress an entire srcBuffer into a valid LZ4 frame, in a single step.
+ * dstBuffer MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr).
+ * The LZ4F_preferences_t structure is optional : you can provide NULL as argument. All preferences will be set to default.
+ * @return : number of bytes written into dstBuffer.
+ * or an error code if it fails (can be tested using LZ4F_isError())
+ */
+size_t LZ4F_compressFrame(void* dstBuffer, size_t dstCapacity,
+ const void* srcBuffer, size_t srcSize,
+ const LZ4F_preferences_t* preferencesPtr)
+{
+ size_t result;
+#if (LZ4F_HEAPMODE)
+ LZ4F_cctx_t* cctxPtr;
+ result = LZ4F_createCompressionContext(&cctxPtr, LZ4F_VERSION);
+ FORWARD_IF_ERROR(result);
+#else
+ LZ4F_cctx_t cctx;
+ LZ4_stream_t lz4ctx;
+ LZ4F_cctx_t* const cctxPtr = &cctx;
+
+ MEM_INIT(&cctx, 0, sizeof(cctx));
+ cctx.version = LZ4F_VERSION;
+ cctx.maxBufferSize = 5 MB; /* mess with real buffer size to prevent dynamic allocation; works only because autoflush==1 & stableSrc==1 */
+ if ( preferencesPtr == NULL
+ || preferencesPtr->compressionLevel < LZ4HC_CLEVEL_MIN ) {
+ LZ4_initStream(&lz4ctx, sizeof(lz4ctx));
+ cctxPtr->lz4CtxPtr = &lz4ctx;
+ cctxPtr->lz4CtxAlloc = 1;
+ cctxPtr->lz4CtxState = 1;
+ }
+#endif
+ DEBUGLOG(4, "LZ4F_compressFrame");
+
+ result = LZ4F_compressFrame_usingCDict(cctxPtr, dstBuffer, dstCapacity,
+ srcBuffer, srcSize,
+ NULL, preferencesPtr);
+
+#if (LZ4F_HEAPMODE)
+ LZ4F_freeCompressionContext(cctxPtr);
+#else
+ if ( preferencesPtr != NULL
+ && preferencesPtr->compressionLevel >= LZ4HC_CLEVEL_MIN ) {
+ LZ4F_free(cctxPtr->lz4CtxPtr, cctxPtr->cmem);
+ }
+#endif
+ return result;
+}
+
+
+/*-***************************************************
+* Dictionary compression
+*****************************************************/
+
+struct LZ4F_CDict_s {
+ LZ4F_CustomMem cmem;
+ void* dictContent;
+ LZ4_stream_t* fastCtx;
+ LZ4_streamHC_t* HCCtx;
+}; /* typedef'd to LZ4F_CDict within lz4frame_static.h */
+
+LZ4F_CDict*
+LZ4F_createCDict_advanced(LZ4F_CustomMem cmem, const void* dictBuffer, size_t dictSize)
+{
+ const char* dictStart = (const char*)dictBuffer;
+ LZ4F_CDict* const cdict = (LZ4F_CDict*)LZ4F_malloc(sizeof(*cdict), cmem);
+ DEBUGLOG(4, "LZ4F_createCDict_advanced");
+ if (!cdict) return NULL;
+ cdict->cmem = cmem;
+ if (dictSize > 64 KB) {
+ dictStart += dictSize - 64 KB;
+ dictSize = 64 KB;
+ }
+ cdict->dictContent = LZ4F_malloc(dictSize, cmem);
+ cdict->fastCtx = (LZ4_stream_t*)LZ4F_malloc(sizeof(LZ4_stream_t), cmem);
+ if (cdict->fastCtx)
+ LZ4_initStream(cdict->fastCtx, sizeof(LZ4_stream_t));
+ cdict->HCCtx = (LZ4_streamHC_t*)LZ4F_malloc(sizeof(LZ4_streamHC_t), cmem);
+ if (cdict->HCCtx)
+ LZ4_initStream(cdict->HCCtx, sizeof(LZ4_streamHC_t));
+ if (!cdict->dictContent || !cdict->fastCtx || !cdict->HCCtx) {
+ LZ4F_freeCDict(cdict);
+ return NULL;
+ }
+ memcpy(cdict->dictContent, dictStart, dictSize);
+ LZ4_loadDict (cdict->fastCtx, (const char*)cdict->dictContent, (int)dictSize);
+ LZ4_setCompressionLevel(cdict->HCCtx, LZ4HC_CLEVEL_DEFAULT);
+ LZ4_loadDictHC(cdict->HCCtx, (const char*)cdict->dictContent, (int)dictSize);
+ return cdict;
+}
+
+/*! LZ4F_createCDict() :
+ * When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
+ * LZ4F_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
+ * LZ4F_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
+ * @dictBuffer can be released after LZ4F_CDict creation, since its content is copied within CDict
+ * @return : digested dictionary for compression, or NULL if failed */
+LZ4F_CDict* LZ4F_createCDict(const void* dictBuffer, size_t dictSize)
+{
+ DEBUGLOG(4, "LZ4F_createCDict");
+ return LZ4F_createCDict_advanced(LZ4F_defaultCMem, dictBuffer, dictSize);
+}
+
+void LZ4F_freeCDict(LZ4F_CDict* cdict)
+{
+ if (cdict==NULL) return; /* support free on NULL */
+ LZ4F_free(cdict->dictContent, cdict->cmem);
+ LZ4F_free(cdict->fastCtx, cdict->cmem);
+ LZ4F_free(cdict->HCCtx, cdict->cmem);
+ LZ4F_free(cdict, cdict->cmem);
+}
+
+
+/*-*********************************
+* Advanced compression functions
+***********************************/
+
+LZ4F_cctx*
+LZ4F_createCompressionContext_advanced(LZ4F_CustomMem customMem, unsigned version)
+{
+ LZ4F_cctx* const cctxPtr =
+ (LZ4F_cctx*)LZ4F_calloc(sizeof(LZ4F_cctx), customMem);
+ if (cctxPtr==NULL) return NULL;
+
+ cctxPtr->cmem = customMem;
+ cctxPtr->version = version;
+ cctxPtr->cStage = 0; /* Uninitialized. Next stage : init cctx */
+
+ return cctxPtr;
+}
+
+/*! LZ4F_createCompressionContext() :
+ * The first thing to do is to create a compressionContext object, which will be used in all compression operations.
+ * This is achieved using LZ4F_createCompressionContext(), which takes as argument a version and an LZ4F_preferences_t structure.
+ * The version provided MUST be LZ4F_VERSION. It is intended to track potential incompatible differences between different binaries.
+ * The function will provide a pointer to an allocated LZ4F_compressionContext_t object.
+ * If the result LZ4F_errorCode_t is not OK_NoError, there was an error during context creation.
+ * Object can release its memory using LZ4F_freeCompressionContext();
+**/
+LZ4F_errorCode_t
+LZ4F_createCompressionContext(LZ4F_cctx** LZ4F_compressionContextPtr, unsigned version)
+{
+ assert(LZ4F_compressionContextPtr != NULL); /* considered a violation of narrow contract */
+ /* in case it nonetheless happen in production */
+ RETURN_ERROR_IF(LZ4F_compressionContextPtr == NULL, parameter_null);
+
+ *LZ4F_compressionContextPtr = LZ4F_createCompressionContext_advanced(LZ4F_defaultCMem, version);
+ RETURN_ERROR_IF(*LZ4F_compressionContextPtr==NULL, allocation_failed);
+ return LZ4F_OK_NoError;
+}
+
+
+LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_cctx* cctxPtr)
+{
+ if (cctxPtr != NULL) { /* support free on NULL */
+ LZ4F_free(cctxPtr->lz4CtxPtr, cctxPtr->cmem); /* note: LZ4_streamHC_t and LZ4_stream_t are simple POD types */
+ LZ4F_free(cctxPtr->tmpBuff, cctxPtr->cmem);
+ LZ4F_free(cctxPtr, cctxPtr->cmem);
+ }
+ return LZ4F_OK_NoError;
+}
+
+
+/**
+ * This function prepares the internal LZ4(HC) stream for a new compression,
+ * resetting the context and attaching the dictionary, if there is one.
+ *
+ * It needs to be called at the beginning of each independent compression
+ * stream (i.e., at the beginning of a frame in blockLinked mode, or at the
+ * beginning of each block in blockIndependent mode).
+ */
+static void LZ4F_initStream(void* ctx,
+ const LZ4F_CDict* cdict,
+ int level,
+ LZ4F_blockMode_t blockMode) {
+ if (level < LZ4HC_CLEVEL_MIN) {
+ if (cdict != NULL || blockMode == LZ4F_blockLinked) {
+ /* In these cases, we will call LZ4_compress_fast_continue(),
+ * which needs an already reset context. Otherwise, we'll call a
+ * one-shot API. The non-continued APIs internally perform their own
+ * resets at the beginning of their calls, where they know what
+ * tableType they need the context to be in. So in that case this
+ * would be misguided / wasted work. */
+ LZ4_resetStream_fast((LZ4_stream_t*)ctx);
+ }
+ LZ4_attach_dictionary((LZ4_stream_t *)ctx, cdict ? cdict->fastCtx : NULL);
+ } else {
+ LZ4_resetStreamHC_fast((LZ4_streamHC_t*)ctx, level);
+ LZ4_attach_HC_dictionary((LZ4_streamHC_t *)ctx, cdict ? cdict->HCCtx : NULL);
+ }
+}
+
+static int ctxTypeID_to_size(int ctxTypeID) {
+ switch(ctxTypeID) {
+ case 1:
+ return LZ4_sizeofState();
+ case 2:
+ return LZ4_sizeofStateHC();
+ default:
+ return 0;
+ }
+}
+
+/*! LZ4F_compressBegin_usingCDict() :
+ * init streaming compression AND writes frame header into @dstBuffer.
+ * @dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes.
+ * @return : number of bytes written into @dstBuffer for the header
+ * or an error code (can be tested using LZ4F_isError())
+ */
+size_t LZ4F_compressBegin_usingCDict(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const LZ4F_CDict* cdict,
+ const LZ4F_preferences_t* preferencesPtr)
+{
+ LZ4F_preferences_t const prefNull = LZ4F_INIT_PREFERENCES;
+ BYTE* const dstStart = (BYTE*)dstBuffer;
+ BYTE* dstPtr = dstStart;
+
+ RETURN_ERROR_IF(dstCapacity < maxFHSize, dstMaxSize_tooSmall);
+ if (preferencesPtr == NULL) preferencesPtr = &prefNull;
+ cctxPtr->prefs = *preferencesPtr;
+
+ /* cctx Management */
+ { U16 const ctxTypeID = (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) ? 1 : 2;
+ int requiredSize = ctxTypeID_to_size(ctxTypeID);
+ int allocatedSize = ctxTypeID_to_size(cctxPtr->lz4CtxAlloc);
+ if (allocatedSize < requiredSize) {
+ /* not enough space allocated */
+ LZ4F_free(cctxPtr->lz4CtxPtr, cctxPtr->cmem);
+ if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) {
+ /* must take ownership of memory allocation,
+ * in order to respect custom allocator contract */
+ cctxPtr->lz4CtxPtr = LZ4F_malloc(sizeof(LZ4_stream_t), cctxPtr->cmem);
+ if (cctxPtr->lz4CtxPtr)
+ LZ4_initStream(cctxPtr->lz4CtxPtr, sizeof(LZ4_stream_t));
+ } else {
+ cctxPtr->lz4CtxPtr = LZ4F_malloc(sizeof(LZ4_streamHC_t), cctxPtr->cmem);
+ if (cctxPtr->lz4CtxPtr)
+ LZ4_initStreamHC(cctxPtr->lz4CtxPtr, sizeof(LZ4_streamHC_t));
+ }
+ RETURN_ERROR_IF(cctxPtr->lz4CtxPtr == NULL, allocation_failed);
+ cctxPtr->lz4CtxAlloc = ctxTypeID;
+ cctxPtr->lz4CtxState = ctxTypeID;
+ } else if (cctxPtr->lz4CtxState != ctxTypeID) {
+ /* otherwise, a sufficient buffer is already allocated,
+ * but we need to reset it to the correct context type */
+ if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN) {
+ LZ4_initStream((LZ4_stream_t*)cctxPtr->lz4CtxPtr, sizeof(LZ4_stream_t));
+ } else {
+ LZ4_initStreamHC((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, sizeof(LZ4_streamHC_t));
+ LZ4_setCompressionLevel((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel);
+ }
+ cctxPtr->lz4CtxState = ctxTypeID;
+ } }
+
+ /* Buffer Management */
+ if (cctxPtr->prefs.frameInfo.blockSizeID == 0)
+ cctxPtr->prefs.frameInfo.blockSizeID = LZ4F_BLOCKSIZEID_DEFAULT;
+ cctxPtr->maxBlockSize = LZ4F_getBlockSize(cctxPtr->prefs.frameInfo.blockSizeID);
+
+ { size_t const requiredBuffSize = preferencesPtr->autoFlush ?
+ ((cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) ? 64 KB : 0) : /* only needs past data up to window size */
+ cctxPtr->maxBlockSize + ((cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) ? 128 KB : 0);
+
+ if (cctxPtr->maxBufferSize < requiredBuffSize) {
+ cctxPtr->maxBufferSize = 0;
+ LZ4F_free(cctxPtr->tmpBuff, cctxPtr->cmem);
+ cctxPtr->tmpBuff = (BYTE*)LZ4F_calloc(requiredBuffSize, cctxPtr->cmem);
+ RETURN_ERROR_IF(cctxPtr->tmpBuff == NULL, allocation_failed);
+ cctxPtr->maxBufferSize = requiredBuffSize;
+ } }
+ cctxPtr->tmpIn = cctxPtr->tmpBuff;
+ cctxPtr->tmpInSize = 0;
+ (void)XXH32_reset(&(cctxPtr->xxh), 0);
+
+ /* context init */
+ cctxPtr->cdict = cdict;
+ if (cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked) {
+ /* frame init only for blockLinked : blockIndependent will be init at each block */
+ LZ4F_initStream(cctxPtr->lz4CtxPtr, cdict, cctxPtr->prefs.compressionLevel, LZ4F_blockLinked);
+ }
+ if (preferencesPtr->compressionLevel >= LZ4HC_CLEVEL_MIN) {
+ LZ4_favorDecompressionSpeed((LZ4_streamHC_t*)cctxPtr->lz4CtxPtr, (int)preferencesPtr->favorDecSpeed);
+ }
+
+ /* Magic Number */
+ LZ4F_writeLE32(dstPtr, LZ4F_MAGICNUMBER);
+ dstPtr += 4;
+ { BYTE* const headerStart = dstPtr;
+
+ /* FLG Byte */
+ *dstPtr++ = (BYTE)(((1 & _2BITS) << 6) /* Version('01') */
+ + ((cctxPtr->prefs.frameInfo.blockMode & _1BIT ) << 5)
+ + ((cctxPtr->prefs.frameInfo.blockChecksumFlag & _1BIT ) << 4)
+ + ((unsigned)(cctxPtr->prefs.frameInfo.contentSize > 0) << 3)
+ + ((cctxPtr->prefs.frameInfo.contentChecksumFlag & _1BIT ) << 2)
+ + (cctxPtr->prefs.frameInfo.dictID > 0) );
+ /* BD Byte */
+ *dstPtr++ = (BYTE)((cctxPtr->prefs.frameInfo.blockSizeID & _3BITS) << 4);
+ /* Optional Frame content size field */
+ if (cctxPtr->prefs.frameInfo.contentSize) {
+ LZ4F_writeLE64(dstPtr, cctxPtr->prefs.frameInfo.contentSize);
+ dstPtr += 8;
+ cctxPtr->totalInSize = 0;
+ }
+ /* Optional dictionary ID field */
+ if (cctxPtr->prefs.frameInfo.dictID) {
+ LZ4F_writeLE32(dstPtr, cctxPtr->prefs.frameInfo.dictID);
+ dstPtr += 4;
+ }
+ /* Header CRC Byte */
+ *dstPtr = LZ4F_headerChecksum(headerStart, (size_t)(dstPtr - headerStart));
+ dstPtr++;
+ }
+
+ cctxPtr->cStage = 1; /* header written, now request input data block */
+ return (size_t)(dstPtr - dstStart);
+}
+
+
+/*! LZ4F_compressBegin() :
+ * init streaming compression AND writes frame header into @dstBuffer.
+ * @dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes.
+ * @preferencesPtr can be NULL, in which case default parameters are selected.
+ * @return : number of bytes written into dstBuffer for the header
+ * or an error code (can be tested using LZ4F_isError())
+ */
+size_t LZ4F_compressBegin(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const LZ4F_preferences_t* preferencesPtr)
+{
+ return LZ4F_compressBegin_usingCDict(cctxPtr, dstBuffer, dstCapacity,
+ NULL, preferencesPtr);
+}
+
+
+/* LZ4F_compressBound() :
+ * @return minimum capacity of dstBuffer for a given srcSize to handle worst case scenario.
+ * LZ4F_preferences_t structure is optional : if NULL, preferences will be set to cover worst case scenario.
+ * This function cannot fail.
+ */
+size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr)
+{
+ if (preferencesPtr && preferencesPtr->autoFlush) {
+ return LZ4F_compressBound_internal(srcSize, preferencesPtr, 0);
+ }
+ return LZ4F_compressBound_internal(srcSize, preferencesPtr, (size_t)-1);
+}
+
+
+typedef int (*compressFunc_t)(void* ctx, const char* src, char* dst, int srcSize, int dstSize, int level, const LZ4F_CDict* cdict);
+
+
+/*! LZ4F_makeBlock():
+ * compress a single block, add header and optional checksum.
+ * assumption : dst buffer capacity is >= BHSize + srcSize + crcSize
+ */
+static size_t LZ4F_makeBlock(void* dst,
+ const void* src, size_t srcSize,
+ compressFunc_t compress, void* lz4ctx, int level,
+ const LZ4F_CDict* cdict,
+ LZ4F_blockChecksum_t crcFlag)
+{
+ BYTE* const cSizePtr = (BYTE*)dst;
+ U32 cSize;
+ assert(compress != NULL);
+ cSize = (U32)compress(lz4ctx, (const char*)src, (char*)(cSizePtr+BHSize),
+ (int)(srcSize), (int)(srcSize-1),
+ level, cdict);
+
+ if (cSize == 0 || cSize >= srcSize) {
+ cSize = (U32)srcSize;
+ LZ4F_writeLE32(cSizePtr, cSize | LZ4F_BLOCKUNCOMPRESSED_FLAG);
+ memcpy(cSizePtr+BHSize, src, srcSize);
+ } else {
+ LZ4F_writeLE32(cSizePtr, cSize);
+ }
+ if (crcFlag) {
+ U32 const crc32 = XXH32(cSizePtr+BHSize, cSize, 0); /* checksum of compressed data */
+ LZ4F_writeLE32(cSizePtr+BHSize+cSize, crc32);
+ }
+ return BHSize + cSize + ((U32)crcFlag)*BFSize;
+}
+
+
+static int LZ4F_compressBlock(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict)
+{
+ int const acceleration = (level < 0) ? -level + 1 : 1;
+ DEBUGLOG(5, "LZ4F_compressBlock (srcSize=%i)", srcSize);
+ LZ4F_initStream(ctx, cdict, level, LZ4F_blockIndependent);
+ if (cdict) {
+ return LZ4_compress_fast_continue((LZ4_stream_t*)ctx, src, dst, srcSize, dstCapacity, acceleration);
+ } else {
+ return LZ4_compress_fast_extState_fastReset(ctx, src, dst, srcSize, dstCapacity, acceleration);
+ }
+}
+
+static int LZ4F_compressBlock_continue(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict)
+{
+ int const acceleration = (level < 0) ? -level + 1 : 1;
+ (void)cdict; /* init once at beginning of frame */
+ DEBUGLOG(5, "LZ4F_compressBlock_continue (srcSize=%i)", srcSize);
+ return LZ4_compress_fast_continue((LZ4_stream_t*)ctx, src, dst, srcSize, dstCapacity, acceleration);
+}
+
+static int LZ4F_compressBlockHC(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict)
+{
+ LZ4F_initStream(ctx, cdict, level, LZ4F_blockIndependent);
+ if (cdict) {
+ return LZ4_compress_HC_continue((LZ4_streamHC_t*)ctx, src, dst, srcSize, dstCapacity);
+ }
+ return LZ4_compress_HC_extStateHC_fastReset(ctx, src, dst, srcSize, dstCapacity, level);
+}
+
+static int LZ4F_compressBlockHC_continue(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict)
+{
+ (void)level; (void)cdict; /* init once at beginning of frame */
+ return LZ4_compress_HC_continue((LZ4_streamHC_t*)ctx, src, dst, srcSize, dstCapacity);
+}
+
+static int LZ4F_doNotCompressBlock(void* ctx, const char* src, char* dst, int srcSize, int dstCapacity, int level, const LZ4F_CDict* cdict)
+{
+ (void)ctx; (void)src; (void)dst; (void)srcSize; (void)dstCapacity; (void)level; (void)cdict;
+ return 0;
+}
+
+static compressFunc_t LZ4F_selectCompression(LZ4F_blockMode_t blockMode, int level, LZ4F_blockCompression_t compressMode)
+{
+ if (compressMode == LZ4B_UNCOMPRESSED) return LZ4F_doNotCompressBlock;
+ if (level < LZ4HC_CLEVEL_MIN) {
+ if (blockMode == LZ4F_blockIndependent) return LZ4F_compressBlock;
+ return LZ4F_compressBlock_continue;
+ }
+ if (blockMode == LZ4F_blockIndependent) return LZ4F_compressBlockHC;
+ return LZ4F_compressBlockHC_continue;
+}
+
+/* Save history (up to 64KB) into @tmpBuff */
+static int LZ4F_localSaveDict(LZ4F_cctx_t* cctxPtr)
+{
+ if (cctxPtr->prefs.compressionLevel < LZ4HC_CLEVEL_MIN)
+ return LZ4_saveDict ((LZ4_stream_t*)(cctxPtr->lz4CtxPtr), (char*)(cctxPtr->tmpBuff), 64 KB);
+ return LZ4_saveDictHC ((LZ4_streamHC_t*)(cctxPtr->lz4CtxPtr), (char*)(cctxPtr->tmpBuff), 64 KB);
+}
+
+typedef enum { notDone, fromTmpBuffer, fromSrcBuffer } LZ4F_lastBlockStatus;
+
+static const LZ4F_compressOptions_t k_cOptionsNull = { 0, { 0, 0, 0 } };
+
+
+ /*! LZ4F_compressUpdateImpl() :
+ * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary.
+ * When successful, the function always entirely consumes @srcBuffer.
+ * src data is either buffered or compressed into @dstBuffer.
+ * If the block compression does not match the compression of the previous block, the old data is flushed
+ * and operations continue with the new compression mode.
+ * @dstCapacity MUST be >= LZ4F_compressBound(srcSize, preferencesPtr) when block compression is turned on.
+ * @compressOptionsPtr is optional : provide NULL to mean "default".
+ * @return : the number of bytes written into dstBuffer. It can be zero, meaning input data was just buffered.
+ * or an error code if it fails (which can be tested using LZ4F_isError())
+ * After an error, the state is left in a UB state, and must be re-initialized.
+ */
+static size_t LZ4F_compressUpdateImpl(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const void* srcBuffer, size_t srcSize,
+ const LZ4F_compressOptions_t* compressOptionsPtr,
+ LZ4F_blockCompression_t blockCompression)
+ {
+ size_t const blockSize = cctxPtr->maxBlockSize;
+ const BYTE* srcPtr = (const BYTE*)srcBuffer;
+ const BYTE* const srcEnd = srcPtr + srcSize;
+ BYTE* const dstStart = (BYTE*)dstBuffer;
+ BYTE* dstPtr = dstStart;
+ LZ4F_lastBlockStatus lastBlockCompressed = notDone;
+ compressFunc_t const compress = LZ4F_selectCompression(cctxPtr->prefs.frameInfo.blockMode, cctxPtr->prefs.compressionLevel, blockCompression);
+ size_t bytesWritten;
+ DEBUGLOG(4, "LZ4F_compressUpdate (srcSize=%zu)", srcSize);
+
+ RETURN_ERROR_IF(cctxPtr->cStage != 1, compressionState_uninitialized); /* state must be initialized and waiting for next block */
+ if (dstCapacity < LZ4F_compressBound_internal(srcSize, &(cctxPtr->prefs), cctxPtr->tmpInSize))
+ RETURN_ERROR(dstMaxSize_tooSmall);
+
+ if (blockCompression == LZ4B_UNCOMPRESSED && dstCapacity < srcSize)
+ RETURN_ERROR(dstMaxSize_tooSmall);
+
+ /* flush currently written block, to continue with new block compression */
+ if (cctxPtr->blockCompression != blockCompression) {
+ bytesWritten = LZ4F_flush(cctxPtr, dstBuffer, dstCapacity, compressOptionsPtr);
+ dstPtr += bytesWritten;
+ cctxPtr->blockCompression = blockCompression;
+ }
+
+ if (compressOptionsPtr == NULL) compressOptionsPtr = &k_cOptionsNull;
+
+ /* complete tmp buffer */
+ if (cctxPtr->tmpInSize > 0) { /* some data already within tmp buffer */
+ size_t const sizeToCopy = blockSize - cctxPtr->tmpInSize;
+ assert(blockSize > cctxPtr->tmpInSize);
+ if (sizeToCopy > srcSize) {
+ /* add src to tmpIn buffer */
+ memcpy(cctxPtr->tmpIn + cctxPtr->tmpInSize, srcBuffer, srcSize);
+ srcPtr = srcEnd;
+ cctxPtr->tmpInSize += srcSize;
+ /* still needs some CRC */
+ } else {
+ /* complete tmpIn block and then compress it */
+ lastBlockCompressed = fromTmpBuffer;
+ memcpy(cctxPtr->tmpIn + cctxPtr->tmpInSize, srcBuffer, sizeToCopy);
+ srcPtr += sizeToCopy;
+
+ dstPtr += LZ4F_makeBlock(dstPtr,
+ cctxPtr->tmpIn, blockSize,
+ compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel,
+ cctxPtr->cdict,
+ cctxPtr->prefs.frameInfo.blockChecksumFlag);
+ if (cctxPtr->prefs.frameInfo.blockMode==LZ4F_blockLinked) cctxPtr->tmpIn += blockSize;
+ cctxPtr->tmpInSize = 0;
+ } }
+
+ while ((size_t)(srcEnd - srcPtr) >= blockSize) {
+ /* compress full blocks */
+ lastBlockCompressed = fromSrcBuffer;
+ dstPtr += LZ4F_makeBlock(dstPtr,
+ srcPtr, blockSize,
+ compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel,
+ cctxPtr->cdict,
+ cctxPtr->prefs.frameInfo.blockChecksumFlag);
+ srcPtr += blockSize;
+ }
+
+ if ((cctxPtr->prefs.autoFlush) && (srcPtr < srcEnd)) {
+ /* autoFlush : remaining input (< blockSize) is compressed */
+ lastBlockCompressed = fromSrcBuffer;
+ dstPtr += LZ4F_makeBlock(dstPtr,
+ srcPtr, (size_t)(srcEnd - srcPtr),
+ compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel,
+ cctxPtr->cdict,
+ cctxPtr->prefs.frameInfo.blockChecksumFlag);
+ srcPtr = srcEnd;
+ }
+
+ /* preserve dictionary within @tmpBuff whenever necessary */
+ if ((cctxPtr->prefs.frameInfo.blockMode==LZ4F_blockLinked) && (lastBlockCompressed==fromSrcBuffer)) {
+ /* linked blocks are only supported in compressed mode, see LZ4F_uncompressedUpdate */
+ assert(blockCompression == LZ4B_COMPRESSED);
+ if (compressOptionsPtr->stableSrc) {
+ cctxPtr->tmpIn = cctxPtr->tmpBuff; /* src is stable : dictionary remains in src across invocations */
+ } else {
+ int const realDictSize = LZ4F_localSaveDict(cctxPtr);
+ assert(0 <= realDictSize && realDictSize <= 64 KB);
+ cctxPtr->tmpIn = cctxPtr->tmpBuff + realDictSize;
+ }
+ }
+
+ /* keep tmpIn within limits */
+ if (!(cctxPtr->prefs.autoFlush) /* no autoflush : there may be some data left within internal buffer */
+ && (cctxPtr->tmpIn + blockSize) > (cctxPtr->tmpBuff + cctxPtr->maxBufferSize) ) /* not enough room to store next block */
+ {
+ /* only preserve 64KB within internal buffer. Ensures there is enough room for next block.
+ * note: this situation necessarily implies lastBlockCompressed==fromTmpBuffer */
+ int const realDictSize = LZ4F_localSaveDict(cctxPtr);
+ cctxPtr->tmpIn = cctxPtr->tmpBuff + realDictSize;
+ assert((cctxPtr->tmpIn + blockSize) <= (cctxPtr->tmpBuff + cctxPtr->maxBufferSize));
+ }
+
+ /* some input data left, necessarily < blockSize */
+ if (srcPtr < srcEnd) {
+ /* fill tmp buffer */
+ size_t const sizeToCopy = (size_t)(srcEnd - srcPtr);
+ memcpy(cctxPtr->tmpIn, srcPtr, sizeToCopy);
+ cctxPtr->tmpInSize = sizeToCopy;
+ }
+
+ if (cctxPtr->prefs.frameInfo.contentChecksumFlag == LZ4F_contentChecksumEnabled)
+ (void)XXH32_update(&(cctxPtr->xxh), srcBuffer, srcSize);
+
+ cctxPtr->totalInSize += srcSize;
+ return (size_t)(dstPtr - dstStart);
+}
+
+/*! LZ4F_compressUpdate() :
+ * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary.
+ * When successful, the function always entirely consumes @srcBuffer.
+ * src data is either buffered or compressed into @dstBuffer.
+ * If previously an uncompressed block was written, buffered data is flushed
+ * before appending compressed data is continued.
+ * @dstCapacity MUST be >= LZ4F_compressBound(srcSize, preferencesPtr).
+ * @compressOptionsPtr is optional : provide NULL to mean "default".
+ * @return : the number of bytes written into dstBuffer. It can be zero, meaning input data was just buffered.
+ * or an error code if it fails (which can be tested using LZ4F_isError())
+ * After an error, the state is left in a UB state, and must be re-initialized.
+ */
+size_t LZ4F_compressUpdate(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const void* srcBuffer, size_t srcSize,
+ const LZ4F_compressOptions_t* compressOptionsPtr)
+{
+ return LZ4F_compressUpdateImpl(cctxPtr,
+ dstBuffer, dstCapacity,
+ srcBuffer, srcSize,
+ compressOptionsPtr, LZ4B_COMPRESSED);
+}
+
+/*! LZ4F_compressUpdate() :
+ * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary.
+ * When successful, the function always entirely consumes @srcBuffer.
+ * src data is either buffered or compressed into @dstBuffer.
+ * If previously an uncompressed block was written, buffered data is flushed
+ * before appending compressed data is continued.
+ * This is only supported when LZ4F_blockIndependent is used
+ * @dstCapacity MUST be >= LZ4F_compressBound(srcSize, preferencesPtr).
+ * @compressOptionsPtr is optional : provide NULL to mean "default".
+ * @return : the number of bytes written into dstBuffer. It can be zero, meaning input data was just buffered.
+ * or an error code if it fails (which can be tested using LZ4F_isError())
+ * After an error, the state is left in a UB state, and must be re-initialized.
+ */
+size_t LZ4F_uncompressedUpdate(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const void* srcBuffer, size_t srcSize,
+ const LZ4F_compressOptions_t* compressOptionsPtr) {
+ RETURN_ERROR_IF(cctxPtr->prefs.frameInfo.blockMode != LZ4F_blockIndependent, blockMode_invalid);
+ return LZ4F_compressUpdateImpl(cctxPtr,
+ dstBuffer, dstCapacity,
+ srcBuffer, srcSize,
+ compressOptionsPtr, LZ4B_UNCOMPRESSED);
+}
+
+
+/*! LZ4F_flush() :
+ * When compressed data must be sent immediately, without waiting for a block to be filled,
+ * invoke LZ4_flush(), which will immediately compress any remaining data stored within LZ4F_cctx.
+ * The result of the function is the number of bytes written into dstBuffer.
+ * It can be zero, this means there was no data left within LZ4F_cctx.
+ * The function outputs an error code if it fails (can be tested using LZ4F_isError())
+ * LZ4F_compressOptions_t* is optional. NULL is a valid argument.
+ */
+size_t LZ4F_flush(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const LZ4F_compressOptions_t* compressOptionsPtr)
+{
+ BYTE* const dstStart = (BYTE*)dstBuffer;
+ BYTE* dstPtr = dstStart;
+ compressFunc_t compress;
+
+ if (cctxPtr->tmpInSize == 0) return 0; /* nothing to flush */
+ RETURN_ERROR_IF(cctxPtr->cStage != 1, compressionState_uninitialized);
+ RETURN_ERROR_IF(dstCapacity < (cctxPtr->tmpInSize + BHSize + BFSize), dstMaxSize_tooSmall);
+ (void)compressOptionsPtr; /* not useful (yet) */
+
+ /* select compression function */
+ compress = LZ4F_selectCompression(cctxPtr->prefs.frameInfo.blockMode, cctxPtr->prefs.compressionLevel, cctxPtr->blockCompression);
+
+ /* compress tmp buffer */
+ dstPtr += LZ4F_makeBlock(dstPtr,
+ cctxPtr->tmpIn, cctxPtr->tmpInSize,
+ compress, cctxPtr->lz4CtxPtr, cctxPtr->prefs.compressionLevel,
+ cctxPtr->cdict,
+ cctxPtr->prefs.frameInfo.blockChecksumFlag);
+ assert(((void)"flush overflows dstBuffer!", (size_t)(dstPtr - dstStart) <= dstCapacity));
+
+ if (cctxPtr->prefs.frameInfo.blockMode == LZ4F_blockLinked)
+ cctxPtr->tmpIn += cctxPtr->tmpInSize;
+ cctxPtr->tmpInSize = 0;
+
+ /* keep tmpIn within limits */
+ if ((cctxPtr->tmpIn + cctxPtr->maxBlockSize) > (cctxPtr->tmpBuff + cctxPtr->maxBufferSize)) { /* necessarily LZ4F_blockLinked */
+ int const realDictSize = LZ4F_localSaveDict(cctxPtr);
+ cctxPtr->tmpIn = cctxPtr->tmpBuff + realDictSize;
+ }
+
+ return (size_t)(dstPtr - dstStart);
+}
+
+
+/*! LZ4F_compressEnd() :
+ * When you want to properly finish the compressed frame, just call LZ4F_compressEnd().
+ * It will flush whatever data remained within compressionContext (like LZ4_flush())
+ * but also properly finalize the frame, with an endMark and an (optional) checksum.
+ * LZ4F_compressOptions_t structure is optional : you can provide NULL as argument.
+ * @return: the number of bytes written into dstBuffer (necessarily >= 4 (endMark size))
+ * or an error code if it fails (can be tested using LZ4F_isError())
+ * The context can then be used again to compress a new frame, starting with LZ4F_compressBegin().
+ */
+size_t LZ4F_compressEnd(LZ4F_cctx* cctxPtr,
+ void* dstBuffer, size_t dstCapacity,
+ const LZ4F_compressOptions_t* compressOptionsPtr)
+{
+ BYTE* const dstStart = (BYTE*)dstBuffer;
+ BYTE* dstPtr = dstStart;
+
+ size_t const flushSize = LZ4F_flush(cctxPtr, dstBuffer, dstCapacity, compressOptionsPtr);
+ DEBUGLOG(5,"LZ4F_compressEnd: dstCapacity=%u", (unsigned)dstCapacity);
+ FORWARD_IF_ERROR(flushSize);
+ dstPtr += flushSize;
+
+ assert(flushSize <= dstCapacity);
+ dstCapacity -= flushSize;
+
+ RETURN_ERROR_IF(dstCapacity < 4, dstMaxSize_tooSmall);
+ LZ4F_writeLE32(dstPtr, 0);
+ dstPtr += 4; /* endMark */
+
+ if (cctxPtr->prefs.frameInfo.contentChecksumFlag == LZ4F_contentChecksumEnabled) {
+ U32 const xxh = XXH32_digest(&(cctxPtr->xxh));
+ RETURN_ERROR_IF(dstCapacity < 8, dstMaxSize_tooSmall);
+ DEBUGLOG(5,"Writing 32-bit content checksum");
+ LZ4F_writeLE32(dstPtr, xxh);
+ dstPtr+=4; /* content Checksum */
+ }
+
+ cctxPtr->cStage = 0; /* state is now re-usable (with identical preferences) */
+ cctxPtr->maxBufferSize = 0; /* reuse HC context */
+
+ if (cctxPtr->prefs.frameInfo.contentSize) {
+ if (cctxPtr->prefs.frameInfo.contentSize != cctxPtr->totalInSize)
+ RETURN_ERROR(frameSize_wrong);
+ }
+
+ return (size_t)(dstPtr - dstStart);
+}
+
+
+/*-***************************************************
+* Frame Decompression
+*****************************************************/
+
+typedef enum {
+ dstage_getFrameHeader=0, dstage_storeFrameHeader,
+ dstage_init,
+ dstage_getBlockHeader, dstage_storeBlockHeader,
+ dstage_copyDirect, dstage_getBlockChecksum,
+ dstage_getCBlock, dstage_storeCBlock,
+ dstage_flushOut,
+ dstage_getSuffix, dstage_storeSuffix,
+ dstage_getSFrameSize, dstage_storeSFrameSize,
+ dstage_skipSkippable
+} dStage_t;
+
+struct LZ4F_dctx_s {
+ LZ4F_CustomMem cmem;
+ LZ4F_frameInfo_t frameInfo;
+ U32 version;
+ dStage_t dStage;
+ U64 frameRemainingSize;
+ size_t maxBlockSize;
+ size_t maxBufferSize;
+ BYTE* tmpIn;
+ size_t tmpInSize;
+ size_t tmpInTarget;
+ BYTE* tmpOutBuffer;
+ const BYTE* dict;
+ size_t dictSize;
+ BYTE* tmpOut;
+ size_t tmpOutSize;
+ size_t tmpOutStart;
+ XXH32_state_t xxh;
+ XXH32_state_t blockChecksum;
+ int skipChecksum;
+ BYTE header[LZ4F_HEADER_SIZE_MAX];
+}; /* typedef'd to LZ4F_dctx in lz4frame.h */
+
+
+LZ4F_dctx* LZ4F_createDecompressionContext_advanced(LZ4F_CustomMem customMem, unsigned version)
+{
+ LZ4F_dctx* const dctx = (LZ4F_dctx*)LZ4F_calloc(sizeof(LZ4F_dctx), customMem);
+ if (dctx == NULL) return NULL;
+
+ dctx->cmem = customMem;
+ dctx->version = version;
+ return dctx;
+}
+
+/*! LZ4F_createDecompressionContext() :
+ * Create a decompressionContext object, which will track all decompression operations.
+ * Provides a pointer to a fully allocated and initialized LZ4F_decompressionContext object.
+ * Object can later be released using LZ4F_freeDecompressionContext().
+ * @return : if != 0, there was an error during context creation.
+ */
+LZ4F_errorCode_t
+LZ4F_createDecompressionContext(LZ4F_dctx** LZ4F_decompressionContextPtr, unsigned versionNumber)
+{
+ assert(LZ4F_decompressionContextPtr != NULL); /* violation of narrow contract */
+ RETURN_ERROR_IF(LZ4F_decompressionContextPtr == NULL, parameter_null); /* in case it nonetheless happen in production */
+
+ *LZ4F_decompressionContextPtr = LZ4F_createDecompressionContext_advanced(LZ4F_defaultCMem, versionNumber);
+ if (*LZ4F_decompressionContextPtr == NULL) { /* failed allocation */
+ RETURN_ERROR(allocation_failed);
+ }
+ return LZ4F_OK_NoError;
+}
+
+LZ4F_errorCode_t LZ4F_freeDecompressionContext(LZ4F_dctx* dctx)
+{
+ LZ4F_errorCode_t result = LZ4F_OK_NoError;
+ if (dctx != NULL) { /* can accept NULL input, like free() */
+ result = (LZ4F_errorCode_t)dctx->dStage;
+ LZ4F_free(dctx->tmpIn, dctx->cmem);
+ LZ4F_free(dctx->tmpOutBuffer, dctx->cmem);
+ LZ4F_free(dctx, dctx->cmem);
+ }
+ return result;
+}
+
+
+/*==--- Streaming Decompression operations ---==*/
+
+void LZ4F_resetDecompressionContext(LZ4F_dctx* dctx)
+{
+ dctx->dStage = dstage_getFrameHeader;
+ dctx->dict = NULL;
+ dctx->dictSize = 0;
+ dctx->skipChecksum = 0;
+}
+
+
+/*! LZ4F_decodeHeader() :
+ * input : `src` points at the **beginning of the frame**
+ * output : set internal values of dctx, such as
+ * dctx->frameInfo and dctx->dStage.
+ * Also allocates internal buffers.
+ * @return : nb Bytes read from src (necessarily <= srcSize)
+ * or an error code (testable with LZ4F_isError())
+ */
+static size_t LZ4F_decodeHeader(LZ4F_dctx* dctx, const void* src, size_t srcSize)
+{
+ unsigned blockMode, blockChecksumFlag, contentSizeFlag, contentChecksumFlag, dictIDFlag, blockSizeID;
+ size_t frameHeaderSize;
+ const BYTE* srcPtr = (const BYTE*)src;
+
+ DEBUGLOG(5, "LZ4F_decodeHeader");
+ /* need to decode header to get frameInfo */
+ RETURN_ERROR_IF(srcSize < minFHSize, frameHeader_incomplete); /* minimal frame header size */
+ MEM_INIT(&(dctx->frameInfo), 0, sizeof(dctx->frameInfo));
+
+ /* special case : skippable frames */
+ if ((LZ4F_readLE32(srcPtr) & 0xFFFFFFF0U) == LZ4F_MAGIC_SKIPPABLE_START) {
+ dctx->frameInfo.frameType = LZ4F_skippableFrame;
+ if (src == (void*)(dctx->header)) {
+ dctx->tmpInSize = srcSize;
+ dctx->tmpInTarget = 8;
+ dctx->dStage = dstage_storeSFrameSize;
+ return srcSize;
+ } else {
+ dctx->dStage = dstage_getSFrameSize;
+ return 4;
+ } }
+
+ /* control magic number */
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ if (LZ4F_readLE32(srcPtr) != LZ4F_MAGICNUMBER) {
+ DEBUGLOG(4, "frame header error : unknown magic number");
+ RETURN_ERROR(frameType_unknown);
+ }
+#endif
+ dctx->frameInfo.frameType = LZ4F_frame;
+
+ /* Flags */
+ { U32 const FLG = srcPtr[4];
+ U32 const version = (FLG>>6) & _2BITS;
+ blockChecksumFlag = (FLG>>4) & _1BIT;
+ blockMode = (FLG>>5) & _1BIT;
+ contentSizeFlag = (FLG>>3) & _1BIT;
+ contentChecksumFlag = (FLG>>2) & _1BIT;
+ dictIDFlag = FLG & _1BIT;
+ /* validate */
+ if (((FLG>>1)&_1BIT) != 0) RETURN_ERROR(reservedFlag_set); /* Reserved bit */
+ if (version != 1) RETURN_ERROR(headerVersion_wrong); /* Version Number, only supported value */
+ }
+
+ /* Frame Header Size */
+ frameHeaderSize = minFHSize + (contentSizeFlag?8:0) + (dictIDFlag?4:0);
+
+ if (srcSize < frameHeaderSize) {
+ /* not enough input to fully decode frame header */
+ if (srcPtr != dctx->header)
+ memcpy(dctx->header, srcPtr, srcSize);
+ dctx->tmpInSize = srcSize;
+ dctx->tmpInTarget = frameHeaderSize;
+ dctx->dStage = dstage_storeFrameHeader;
+ return srcSize;
+ }
+
+ { U32 const BD = srcPtr[5];
+ blockSizeID = (BD>>4) & _3BITS;
+ /* validate */
+ if (((BD>>7)&_1BIT) != 0) RETURN_ERROR(reservedFlag_set); /* Reserved bit */
+ if (blockSizeID < 4) RETURN_ERROR(maxBlockSize_invalid); /* 4-7 only supported values for the time being */
+ if (((BD>>0)&_4BITS) != 0) RETURN_ERROR(reservedFlag_set); /* Reserved bits */
+ }
+
+ /* check header */
+ assert(frameHeaderSize > 5);
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ { BYTE const HC = LZ4F_headerChecksum(srcPtr+4, frameHeaderSize-5);
+ RETURN_ERROR_IF(HC != srcPtr[frameHeaderSize-1], headerChecksum_invalid);
+ }
+#endif
+
+ /* save */
+ dctx->frameInfo.blockMode = (LZ4F_blockMode_t)blockMode;
+ dctx->frameInfo.blockChecksumFlag = (LZ4F_blockChecksum_t)blockChecksumFlag;
+ dctx->frameInfo.contentChecksumFlag = (LZ4F_contentChecksum_t)contentChecksumFlag;
+ dctx->frameInfo.blockSizeID = (LZ4F_blockSizeID_t)blockSizeID;
+ dctx->maxBlockSize = LZ4F_getBlockSize((LZ4F_blockSizeID_t)blockSizeID);
+ if (contentSizeFlag)
+ dctx->frameRemainingSize = dctx->frameInfo.contentSize = LZ4F_readLE64(srcPtr+6);
+ if (dictIDFlag)
+ dctx->frameInfo.dictID = LZ4F_readLE32(srcPtr + frameHeaderSize - 5);
+
+ dctx->dStage = dstage_init;
+
+ return frameHeaderSize;
+}
+
+
+/*! LZ4F_headerSize() :
+ * @return : size of frame header
+ * or an error code, which can be tested using LZ4F_isError()
+ */
+size_t LZ4F_headerSize(const void* src, size_t srcSize)
+{
+ RETURN_ERROR_IF(src == NULL, srcPtr_wrong);
+
+ /* minimal srcSize to determine header size */
+ if (srcSize < LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH)
+ RETURN_ERROR(frameHeader_incomplete);
+
+ /* special case : skippable frames */
+ if ((LZ4F_readLE32(src) & 0xFFFFFFF0U) == LZ4F_MAGIC_SKIPPABLE_START)
+ return 8;
+
+ /* control magic number */
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ if (LZ4F_readLE32(src) != LZ4F_MAGICNUMBER)
+ RETURN_ERROR(frameType_unknown);
+#endif
+
+ /* Frame Header Size */
+ { BYTE const FLG = ((const BYTE*)src)[4];
+ U32 const contentSizeFlag = (FLG>>3) & _1BIT;
+ U32 const dictIDFlag = FLG & _1BIT;
+ return minFHSize + (contentSizeFlag?8:0) + (dictIDFlag?4:0);
+ }
+}
+
+/*! LZ4F_getFrameInfo() :
+ * This function extracts frame parameters (max blockSize, frame checksum, etc.).
+ * Usage is optional. Objective is to provide relevant information for allocation purposes.
+ * This function works in 2 situations :
+ * - At the beginning of a new frame, in which case it will decode this information from `srcBuffer`, and start the decoding process.
+ * Amount of input data provided must be large enough to successfully decode the frame header.
+ * A header size is variable, but is guaranteed to be <= LZ4F_HEADER_SIZE_MAX bytes. It's possible to provide more input data than this minimum.
+ * - After decoding has been started. In which case, no input is read, frame parameters are extracted from dctx.
+ * The number of bytes consumed from srcBuffer will be updated within *srcSizePtr (necessarily <= original value).
+ * Decompression must resume from (srcBuffer + *srcSizePtr).
+ * @return : an hint about how many srcSize bytes LZ4F_decompress() expects for next call,
+ * or an error code which can be tested using LZ4F_isError()
+ * note 1 : in case of error, dctx is not modified. Decoding operations can resume from where they stopped.
+ * note 2 : frame parameters are *copied into* an already allocated LZ4F_frameInfo_t structure.
+ */
+LZ4F_errorCode_t LZ4F_getFrameInfo(LZ4F_dctx* dctx,
+ LZ4F_frameInfo_t* frameInfoPtr,
+ const void* srcBuffer, size_t* srcSizePtr)
+{
+ LZ4F_STATIC_ASSERT(dstage_getFrameHeader < dstage_storeFrameHeader);
+ if (dctx->dStage > dstage_storeFrameHeader) {
+ /* frameInfo already decoded */
+ size_t o=0, i=0;
+ *srcSizePtr = 0;
+ *frameInfoPtr = dctx->frameInfo;
+ /* returns : recommended nb of bytes for LZ4F_decompress() */
+ return LZ4F_decompress(dctx, NULL, &o, NULL, &i, NULL);
+ } else {
+ if (dctx->dStage == dstage_storeFrameHeader) {
+ /* frame decoding already started, in the middle of header => automatic fail */
+ *srcSizePtr = 0;
+ RETURN_ERROR(frameDecoding_alreadyStarted);
+ } else {
+ size_t const hSize = LZ4F_headerSize(srcBuffer, *srcSizePtr);
+ if (LZ4F_isError(hSize)) { *srcSizePtr=0; return hSize; }
+ if (*srcSizePtr < hSize) {
+ *srcSizePtr=0;
+ RETURN_ERROR(frameHeader_incomplete);
+ }
+
+ { size_t decodeResult = LZ4F_decodeHeader(dctx, srcBuffer, hSize);
+ if (LZ4F_isError(decodeResult)) {
+ *srcSizePtr = 0;
+ } else {
+ *srcSizePtr = decodeResult;
+ decodeResult = BHSize; /* block header size */
+ }
+ *frameInfoPtr = dctx->frameInfo;
+ return decodeResult;
+ } } }
+}
+
+
+/* LZ4F_updateDict() :
+ * only used for LZ4F_blockLinked mode
+ * Condition : @dstPtr != NULL
+ */
+static void LZ4F_updateDict(LZ4F_dctx* dctx,
+ const BYTE* dstPtr, size_t dstSize, const BYTE* dstBufferStart,
+ unsigned withinTmp)
+{
+ assert(dstPtr != NULL);
+ if (dctx->dictSize==0) dctx->dict = (const BYTE*)dstPtr; /* will lead to prefix mode */
+ assert(dctx->dict != NULL);
+
+ if (dctx->dict + dctx->dictSize == dstPtr) { /* prefix mode, everything within dstBuffer */
+ dctx->dictSize += dstSize;
+ return;
+ }
+
+ assert(dstPtr >= dstBufferStart);
+ if ((size_t)(dstPtr - dstBufferStart) + dstSize >= 64 KB) { /* history in dstBuffer becomes large enough to become dictionary */
+ dctx->dict = (const BYTE*)dstBufferStart;
+ dctx->dictSize = (size_t)(dstPtr - dstBufferStart) + dstSize;
+ return;
+ }
+
+ assert(dstSize < 64 KB); /* if dstSize >= 64 KB, dictionary would be set into dstBuffer directly */
+
+ /* dstBuffer does not contain whole useful history (64 KB), so it must be saved within tmpOutBuffer */
+ assert(dctx->tmpOutBuffer != NULL);
+
+ if (withinTmp && (dctx->dict == dctx->tmpOutBuffer)) { /* continue history within tmpOutBuffer */
+ /* withinTmp expectation : content of [dstPtr,dstSize] is same as [dict+dictSize,dstSize], so we just extend it */
+ assert(dctx->dict + dctx->dictSize == dctx->tmpOut + dctx->tmpOutStart);
+ dctx->dictSize += dstSize;
+ return;
+ }
+
+ if (withinTmp) { /* copy relevant dict portion in front of tmpOut within tmpOutBuffer */
+ size_t const preserveSize = (size_t)(dctx->tmpOut - dctx->tmpOutBuffer);
+ size_t copySize = 64 KB - dctx->tmpOutSize;
+ const BYTE* const oldDictEnd = dctx->dict + dctx->dictSize - dctx->tmpOutStart;
+ if (dctx->tmpOutSize > 64 KB) copySize = 0;
+ if (copySize > preserveSize) copySize = preserveSize;
+
+ memcpy(dctx->tmpOutBuffer + preserveSize - copySize, oldDictEnd - copySize, copySize);
+
+ dctx->dict = dctx->tmpOutBuffer;
+ dctx->dictSize = preserveSize + dctx->tmpOutStart + dstSize;
+ return;
+ }
+
+ if (dctx->dict == dctx->tmpOutBuffer) { /* copy dst into tmp to complete dict */
+ if (dctx->dictSize + dstSize > dctx->maxBufferSize) { /* tmp buffer not large enough */
+ size_t const preserveSize = 64 KB - dstSize;
+ memcpy(dctx->tmpOutBuffer, dctx->dict + dctx->dictSize - preserveSize, preserveSize);
+ dctx->dictSize = preserveSize;
+ }
+ memcpy(dctx->tmpOutBuffer + dctx->dictSize, dstPtr, dstSize);
+ dctx->dictSize += dstSize;
+ return;
+ }
+
+ /* join dict & dest into tmp */
+ { size_t preserveSize = 64 KB - dstSize;
+ if (preserveSize > dctx->dictSize) preserveSize = dctx->dictSize;
+ memcpy(dctx->tmpOutBuffer, dctx->dict + dctx->dictSize - preserveSize, preserveSize);
+ memcpy(dctx->tmpOutBuffer + preserveSize, dstPtr, dstSize);
+ dctx->dict = dctx->tmpOutBuffer;
+ dctx->dictSize = preserveSize + dstSize;
+ }
+}
+
+
+/*! LZ4F_decompress() :
+ * Call this function repetitively to regenerate compressed data in srcBuffer.
+ * The function will attempt to decode up to *srcSizePtr bytes from srcBuffer
+ * into dstBuffer of capacity *dstSizePtr.
+ *
+ * The number of bytes regenerated into dstBuffer will be provided within *dstSizePtr (necessarily <= original value).
+ *
+ * The number of bytes effectively read from srcBuffer will be provided within *srcSizePtr (necessarily <= original value).
+ * If number of bytes read is < number of bytes provided, then decompression operation is not complete.
+ * Remaining data will have to be presented again in a subsequent invocation.
+ *
+ * The function result is an hint of the better srcSize to use for next call to LZ4F_decompress.
+ * Schematically, it's the size of the current (or remaining) compressed block + header of next block.
+ * Respecting the hint provides a small boost to performance, since it allows less buffer shuffling.
+ * Note that this is just a hint, and it's always possible to any srcSize value.
+ * When a frame is fully decoded, @return will be 0.
+ * If decompression failed, @return is an error code which can be tested using LZ4F_isError().
+ */
+size_t LZ4F_decompress(LZ4F_dctx* dctx,
+ void* dstBuffer, size_t* dstSizePtr,
+ const void* srcBuffer, size_t* srcSizePtr,
+ const LZ4F_decompressOptions_t* decompressOptionsPtr)
+{
+ LZ4F_decompressOptions_t optionsNull;
+ const BYTE* const srcStart = (const BYTE*)srcBuffer;
+ const BYTE* const srcEnd = srcStart + *srcSizePtr;
+ const BYTE* srcPtr = srcStart;
+ BYTE* const dstStart = (BYTE*)dstBuffer;
+ BYTE* const dstEnd = dstStart ? dstStart + *dstSizePtr : NULL;
+ BYTE* dstPtr = dstStart;
+ const BYTE* selectedIn = NULL;
+ unsigned doAnotherStage = 1;
+ size_t nextSrcSizeHint = 1;
+
+
+ DEBUGLOG(5, "LZ4F_decompress : %p,%u => %p,%u",
+ srcBuffer, (unsigned)*srcSizePtr, dstBuffer, (unsigned)*dstSizePtr);
+ if (dstBuffer == NULL) assert(*dstSizePtr == 0);
+ MEM_INIT(&optionsNull, 0, sizeof(optionsNull));
+ if (decompressOptionsPtr==NULL) decompressOptionsPtr = &optionsNull;
+ *srcSizePtr = 0;
+ *dstSizePtr = 0;
+ assert(dctx != NULL);
+ dctx->skipChecksum |= (decompressOptionsPtr->skipChecksums != 0); /* once set, disable for the remainder of the frame */
+
+ /* behaves as a state machine */
+
+ while (doAnotherStage) {
+
+ switch(dctx->dStage)
+ {
+
+ case dstage_getFrameHeader:
+ DEBUGLOG(6, "dstage_getFrameHeader");
+ if ((size_t)(srcEnd-srcPtr) >= maxFHSize) { /* enough to decode - shortcut */
+ size_t const hSize = LZ4F_decodeHeader(dctx, srcPtr, (size_t)(srcEnd-srcPtr)); /* will update dStage appropriately */
+ FORWARD_IF_ERROR(hSize);
+ srcPtr += hSize;
+ break;
+ }
+ dctx->tmpInSize = 0;
+ if (srcEnd-srcPtr == 0) return minFHSize; /* 0-size input */
+ dctx->tmpInTarget = minFHSize; /* minimum size to decode header */
+ dctx->dStage = dstage_storeFrameHeader;
+ /* fall-through */
+
+ case dstage_storeFrameHeader:
+ DEBUGLOG(6, "dstage_storeFrameHeader");
+ { size_t const sizeToCopy = MIN(dctx->tmpInTarget - dctx->tmpInSize, (size_t)(srcEnd - srcPtr));
+ memcpy(dctx->header + dctx->tmpInSize, srcPtr, sizeToCopy);
+ dctx->tmpInSize += sizeToCopy;
+ srcPtr += sizeToCopy;
+ }
+ if (dctx->tmpInSize < dctx->tmpInTarget) {
+ nextSrcSizeHint = (dctx->tmpInTarget - dctx->tmpInSize) + BHSize; /* rest of header + nextBlockHeader */
+ doAnotherStage = 0; /* not enough src data, ask for some more */
+ break;
+ }
+ FORWARD_IF_ERROR( LZ4F_decodeHeader(dctx, dctx->header, dctx->tmpInTarget) ); /* will update dStage appropriately */
+ break;
+
+ case dstage_init:
+ DEBUGLOG(6, "dstage_init");
+ if (dctx->frameInfo.contentChecksumFlag) (void)XXH32_reset(&(dctx->xxh), 0);
+ /* internal buffers allocation */
+ { size_t const bufferNeeded = dctx->maxBlockSize
+ + ((dctx->frameInfo.blockMode==LZ4F_blockLinked) ? 128 KB : 0);
+ if (bufferNeeded > dctx->maxBufferSize) { /* tmp buffers too small */
+ dctx->maxBufferSize = 0; /* ensure allocation will be re-attempted on next entry*/
+ LZ4F_free(dctx->tmpIn, dctx->cmem);
+ dctx->tmpIn = (BYTE*)LZ4F_malloc(dctx->maxBlockSize + BFSize /* block checksum */, dctx->cmem);
+ RETURN_ERROR_IF(dctx->tmpIn == NULL, allocation_failed);
+ LZ4F_free(dctx->tmpOutBuffer, dctx->cmem);
+ dctx->tmpOutBuffer= (BYTE*)LZ4F_malloc(bufferNeeded, dctx->cmem);
+ RETURN_ERROR_IF(dctx->tmpOutBuffer== NULL, allocation_failed);
+ dctx->maxBufferSize = bufferNeeded;
+ } }
+ dctx->tmpInSize = 0;
+ dctx->tmpInTarget = 0;
+ dctx->tmpOut = dctx->tmpOutBuffer;
+ dctx->tmpOutStart = 0;
+ dctx->tmpOutSize = 0;
+
+ dctx->dStage = dstage_getBlockHeader;
+ /* fall-through */
+
+ case dstage_getBlockHeader:
+ if ((size_t)(srcEnd - srcPtr) >= BHSize) {
+ selectedIn = srcPtr;
+ srcPtr += BHSize;
+ } else {
+ /* not enough input to read cBlockSize field */
+ dctx->tmpInSize = 0;
+ dctx->dStage = dstage_storeBlockHeader;
+ }
+
+ if (dctx->dStage == dstage_storeBlockHeader) /* can be skipped */
+ case dstage_storeBlockHeader:
+ { size_t const remainingInput = (size_t)(srcEnd - srcPtr);
+ size_t const wantedData = BHSize - dctx->tmpInSize;
+ size_t const sizeToCopy = MIN(wantedData, remainingInput);
+ memcpy(dctx->tmpIn + dctx->tmpInSize, srcPtr, sizeToCopy);
+ srcPtr += sizeToCopy;
+ dctx->tmpInSize += sizeToCopy;
+
+ if (dctx->tmpInSize < BHSize) { /* not enough input for cBlockSize */
+ nextSrcSizeHint = BHSize - dctx->tmpInSize;
+ doAnotherStage = 0;
+ break;
+ }
+ selectedIn = dctx->tmpIn;
+ } /* if (dctx->dStage == dstage_storeBlockHeader) */
+
+ /* decode block header */
+ { U32 const blockHeader = LZ4F_readLE32(selectedIn);
+ size_t const nextCBlockSize = blockHeader & 0x7FFFFFFFU;
+ size_t const crcSize = dctx->frameInfo.blockChecksumFlag * BFSize;
+ if (blockHeader==0) { /* frameEnd signal, no more block */
+ DEBUGLOG(5, "end of frame");
+ dctx->dStage = dstage_getSuffix;
+ break;
+ }
+ if (nextCBlockSize > dctx->maxBlockSize) {
+ RETURN_ERROR(maxBlockSize_invalid);
+ }
+ if (blockHeader & LZ4F_BLOCKUNCOMPRESSED_FLAG) {
+ /* next block is uncompressed */
+ dctx->tmpInTarget = nextCBlockSize;
+ DEBUGLOG(5, "next block is uncompressed (size %u)", (U32)nextCBlockSize);
+ if (dctx->frameInfo.blockChecksumFlag) {
+ (void)XXH32_reset(&dctx->blockChecksum, 0);
+ }
+ dctx->dStage = dstage_copyDirect;
+ break;
+ }
+ /* next block is a compressed block */
+ dctx->tmpInTarget = nextCBlockSize + crcSize;
+ dctx->dStage = dstage_getCBlock;
+ if (dstPtr==dstEnd || srcPtr==srcEnd) {
+ nextSrcSizeHint = BHSize + nextCBlockSize + crcSize;
+ doAnotherStage = 0;
+ }
+ break;
+ }
+
+ case dstage_copyDirect: /* uncompressed block */
+ DEBUGLOG(6, "dstage_copyDirect");
+ { size_t sizeToCopy;
+ if (dstPtr == NULL) {
+ sizeToCopy = 0;
+ } else {
+ size_t const minBuffSize = MIN((size_t)(srcEnd-srcPtr), (size_t)(dstEnd-dstPtr));
+ sizeToCopy = MIN(dctx->tmpInTarget, minBuffSize);
+ memcpy(dstPtr, srcPtr, sizeToCopy);
+ if (!dctx->skipChecksum) {
+ if (dctx->frameInfo.blockChecksumFlag) {
+ (void)XXH32_update(&dctx->blockChecksum, srcPtr, sizeToCopy);
+ }
+ if (dctx->frameInfo.contentChecksumFlag)
+ (void)XXH32_update(&dctx->xxh, srcPtr, sizeToCopy);
+ }
+ if (dctx->frameInfo.contentSize)
+ dctx->frameRemainingSize -= sizeToCopy;
+
+ /* history management (linked blocks only)*/
+ if (dctx->frameInfo.blockMode == LZ4F_blockLinked) {
+ LZ4F_updateDict(dctx, dstPtr, sizeToCopy, dstStart, 0);
+ } }
+
+ srcPtr += sizeToCopy;
+ dstPtr += sizeToCopy;
+ if (sizeToCopy == dctx->tmpInTarget) { /* all done */
+ if (dctx->frameInfo.blockChecksumFlag) {
+ dctx->tmpInSize = 0;
+ dctx->dStage = dstage_getBlockChecksum;
+ } else
+ dctx->dStage = dstage_getBlockHeader; /* new block */
+ break;
+ }
+ dctx->tmpInTarget -= sizeToCopy; /* need to copy more */
+ }
+ nextSrcSizeHint = dctx->tmpInTarget +
+ +(dctx->frameInfo.blockChecksumFlag ? BFSize : 0)
+ + BHSize /* next header size */;
+ doAnotherStage = 0;
+ break;
+
+ /* check block checksum for recently transferred uncompressed block */
+ case dstage_getBlockChecksum:
+ DEBUGLOG(6, "dstage_getBlockChecksum");
+ { const void* crcSrc;
+ if ((srcEnd-srcPtr >= 4) && (dctx->tmpInSize==0)) {
+ crcSrc = srcPtr;
+ srcPtr += 4;
+ } else {
+ size_t const stillToCopy = 4 - dctx->tmpInSize;
+ size_t const sizeToCopy = MIN(stillToCopy, (size_t)(srcEnd-srcPtr));
+ memcpy(dctx->header + dctx->tmpInSize, srcPtr, sizeToCopy);
+ dctx->tmpInSize += sizeToCopy;
+ srcPtr += sizeToCopy;
+ if (dctx->tmpInSize < 4) { /* all input consumed */
+ doAnotherStage = 0;
+ break;
+ }
+ crcSrc = dctx->header;
+ }
+ if (!dctx->skipChecksum) {
+ U32 const readCRC = LZ4F_readLE32(crcSrc);
+ U32 const calcCRC = XXH32_digest(&dctx->blockChecksum);
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ DEBUGLOG(6, "compare block checksum");
+ if (readCRC != calcCRC) {
+ DEBUGLOG(4, "incorrect block checksum: %08X != %08X",
+ readCRC, calcCRC);
+ RETURN_ERROR(blockChecksum_invalid);
+ }
+#else
+ (void)readCRC;
+ (void)calcCRC;
+#endif
+ } }
+ dctx->dStage = dstage_getBlockHeader; /* new block */
+ break;
+
+ case dstage_getCBlock:
+ DEBUGLOG(6, "dstage_getCBlock");
+ if ((size_t)(srcEnd-srcPtr) < dctx->tmpInTarget) {
+ dctx->tmpInSize = 0;
+ dctx->dStage = dstage_storeCBlock;
+ break;
+ }
+ /* input large enough to read full block directly */
+ selectedIn = srcPtr;
+ srcPtr += dctx->tmpInTarget;
+
+ if (0) /* always jump over next block */
+ case dstage_storeCBlock:
+ { size_t const wantedData = dctx->tmpInTarget - dctx->tmpInSize;
+ size_t const inputLeft = (size_t)(srcEnd-srcPtr);
+ size_t const sizeToCopy = MIN(wantedData, inputLeft);
+ memcpy(dctx->tmpIn + dctx->tmpInSize, srcPtr, sizeToCopy);
+ dctx->tmpInSize += sizeToCopy;
+ srcPtr += sizeToCopy;
+ if (dctx->tmpInSize < dctx->tmpInTarget) { /* need more input */
+ nextSrcSizeHint = (dctx->tmpInTarget - dctx->tmpInSize)
+ + (dctx->frameInfo.blockChecksumFlag ? BFSize : 0)
+ + BHSize /* next header size */;
+ doAnotherStage = 0;
+ break;
+ }
+ selectedIn = dctx->tmpIn;
+ }
+
+ /* At this stage, input is large enough to decode a block */
+
+ /* First, decode and control block checksum if it exists */
+ if (dctx->frameInfo.blockChecksumFlag) {
+ assert(dctx->tmpInTarget >= 4);
+ dctx->tmpInTarget -= 4;
+ assert(selectedIn != NULL); /* selectedIn is defined at this stage (either srcPtr, or dctx->tmpIn) */
+ { U32 const readBlockCrc = LZ4F_readLE32(selectedIn + dctx->tmpInTarget);
+ U32 const calcBlockCrc = XXH32(selectedIn, dctx->tmpInTarget, 0);
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ RETURN_ERROR_IF(readBlockCrc != calcBlockCrc, blockChecksum_invalid);
+#else
+ (void)readBlockCrc;
+ (void)calcBlockCrc;
+#endif
+ } }
+
+ /* decode directly into destination buffer if there is enough room */
+ if ( ((size_t)(dstEnd-dstPtr) >= dctx->maxBlockSize)
+ /* unless the dictionary is stored in tmpOut:
+ * in which case it's faster to decode within tmpOut
+ * to benefit from prefix speedup */
+ && !(dctx->dict!= NULL && (const BYTE*)dctx->dict + dctx->dictSize == dctx->tmpOut) )
+ {
+ const char* dict = (const char*)dctx->dict;
+ size_t dictSize = dctx->dictSize;
+ int decodedSize;
+ assert(dstPtr != NULL);
+ if (dict && dictSize > 1 GB) {
+ /* overflow control : dctx->dictSize is an int, avoid truncation / sign issues */
+ dict += dictSize - 64 KB;
+ dictSize = 64 KB;
+ }
+ decodedSize = LZ4_decompress_safe_usingDict(
+ (const char*)selectedIn, (char*)dstPtr,
+ (int)dctx->tmpInTarget, (int)dctx->maxBlockSize,
+ dict, (int)dictSize);
+ RETURN_ERROR_IF(decodedSize < 0, decompressionFailed);
+ if ((dctx->frameInfo.contentChecksumFlag) && (!dctx->skipChecksum))
+ XXH32_update(&(dctx->xxh), dstPtr, (size_t)decodedSize);
+ if (dctx->frameInfo.contentSize)
+ dctx->frameRemainingSize -= (size_t)decodedSize;
+
+ /* dictionary management */
+ if (dctx->frameInfo.blockMode==LZ4F_blockLinked) {
+ LZ4F_updateDict(dctx, dstPtr, (size_t)decodedSize, dstStart, 0);
+ }
+
+ dstPtr += decodedSize;
+ dctx->dStage = dstage_getBlockHeader; /* end of block, let's get another one */
+ break;
+ }
+
+ /* not enough place into dst : decode into tmpOut */
+
+ /* manage dictionary */
+ if (dctx->frameInfo.blockMode == LZ4F_blockLinked) {
+ if (dctx->dict == dctx->tmpOutBuffer) {
+ /* truncate dictionary to 64 KB if too big */
+ if (dctx->dictSize > 128 KB) {
+ memcpy(dctx->tmpOutBuffer, dctx->dict + dctx->dictSize - 64 KB, 64 KB);
+ dctx->dictSize = 64 KB;
+ }
+ dctx->tmpOut = dctx->tmpOutBuffer + dctx->dictSize;
+ } else { /* dict not within tmpOut */
+ size_t const reservedDictSpace = MIN(dctx->dictSize, 64 KB);
+ dctx->tmpOut = dctx->tmpOutBuffer + reservedDictSpace;
+ } }
+
+ /* Decode block into tmpOut */
+ { const char* dict = (const char*)dctx->dict;
+ size_t dictSize = dctx->dictSize;
+ int decodedSize;
+ if (dict && dictSize > 1 GB) {
+ /* the dictSize param is an int, avoid truncation / sign issues */
+ dict += dictSize - 64 KB;
+ dictSize = 64 KB;
+ }
+ decodedSize = LZ4_decompress_safe_usingDict(
+ (const char*)selectedIn, (char*)dctx->tmpOut,
+ (int)dctx->tmpInTarget, (int)dctx->maxBlockSize,
+ dict, (int)dictSize);
+ RETURN_ERROR_IF(decodedSize < 0, decompressionFailed);
+ if (dctx->frameInfo.contentChecksumFlag && !dctx->skipChecksum)
+ XXH32_update(&(dctx->xxh), dctx->tmpOut, (size_t)decodedSize);
+ if (dctx->frameInfo.contentSize)
+ dctx->frameRemainingSize -= (size_t)decodedSize;
+ dctx->tmpOutSize = (size_t)decodedSize;
+ dctx->tmpOutStart = 0;
+ dctx->dStage = dstage_flushOut;
+ }
+ /* fall-through */
+
+ case dstage_flushOut: /* flush decoded data from tmpOut to dstBuffer */
+ DEBUGLOG(6, "dstage_flushOut");
+ if (dstPtr != NULL) {
+ size_t const sizeToCopy = MIN(dctx->tmpOutSize - dctx->tmpOutStart, (size_t)(dstEnd-dstPtr));
+ memcpy(dstPtr, dctx->tmpOut + dctx->tmpOutStart, sizeToCopy);
+
+ /* dictionary management */
+ if (dctx->frameInfo.blockMode == LZ4F_blockLinked)
+ LZ4F_updateDict(dctx, dstPtr, sizeToCopy, dstStart, 1 /*withinTmp*/);
+
+ dctx->tmpOutStart += sizeToCopy;
+ dstPtr += sizeToCopy;
+ }
+ if (dctx->tmpOutStart == dctx->tmpOutSize) { /* all flushed */
+ dctx->dStage = dstage_getBlockHeader; /* get next block */
+ break;
+ }
+ /* could not flush everything : stop there, just request a block header */
+ doAnotherStage = 0;
+ nextSrcSizeHint = BHSize;
+ break;
+
+ case dstage_getSuffix:
+ RETURN_ERROR_IF(dctx->frameRemainingSize, frameSize_wrong); /* incorrect frame size decoded */
+ if (!dctx->frameInfo.contentChecksumFlag) { /* no checksum, frame is completed */
+ nextSrcSizeHint = 0;
+ LZ4F_resetDecompressionContext(dctx);
+ doAnotherStage = 0;
+ break;
+ }
+ if ((srcEnd - srcPtr) < 4) { /* not enough size for entire CRC */
+ dctx->tmpInSize = 0;
+ dctx->dStage = dstage_storeSuffix;
+ } else {
+ selectedIn = srcPtr;
+ srcPtr += 4;
+ }
+
+ if (dctx->dStage == dstage_storeSuffix) /* can be skipped */
+ case dstage_storeSuffix:
+ { size_t const remainingInput = (size_t)(srcEnd - srcPtr);
+ size_t const wantedData = 4 - dctx->tmpInSize;
+ size_t const sizeToCopy = MIN(wantedData, remainingInput);
+ memcpy(dctx->tmpIn + dctx->tmpInSize, srcPtr, sizeToCopy);
+ srcPtr += sizeToCopy;
+ dctx->tmpInSize += sizeToCopy;
+ if (dctx->tmpInSize < 4) { /* not enough input to read complete suffix */
+ nextSrcSizeHint = 4 - dctx->tmpInSize;
+ doAnotherStage=0;
+ break;
+ }
+ selectedIn = dctx->tmpIn;
+ } /* if (dctx->dStage == dstage_storeSuffix) */
+
+ /* case dstage_checkSuffix: */ /* no direct entry, avoid initialization risks */
+ if (!dctx->skipChecksum) {
+ U32 const readCRC = LZ4F_readLE32(selectedIn);
+ U32 const resultCRC = XXH32_digest(&(dctx->xxh));
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ RETURN_ERROR_IF(readCRC != resultCRC, contentChecksum_invalid);
+#else
+ (void)readCRC;
+ (void)resultCRC;
+#endif
+ }
+ nextSrcSizeHint = 0;
+ LZ4F_resetDecompressionContext(dctx);
+ doAnotherStage = 0;
+ break;
+
+ case dstage_getSFrameSize:
+ if ((srcEnd - srcPtr) >= 4) {
+ selectedIn = srcPtr;
+ srcPtr += 4;
+ } else {
+ /* not enough input to read cBlockSize field */
+ dctx->tmpInSize = 4;
+ dctx->tmpInTarget = 8;
+ dctx->dStage = dstage_storeSFrameSize;
+ }
+
+ if (dctx->dStage == dstage_storeSFrameSize)
+ case dstage_storeSFrameSize:
+ { size_t const sizeToCopy = MIN(dctx->tmpInTarget - dctx->tmpInSize,
+ (size_t)(srcEnd - srcPtr) );
+ memcpy(dctx->header + dctx->tmpInSize, srcPtr, sizeToCopy);
+ srcPtr += sizeToCopy;
+ dctx->tmpInSize += sizeToCopy;
+ if (dctx->tmpInSize < dctx->tmpInTarget) {
+ /* not enough input to get full sBlockSize; wait for more */
+ nextSrcSizeHint = dctx->tmpInTarget - dctx->tmpInSize;
+ doAnotherStage = 0;
+ break;
+ }
+ selectedIn = dctx->header + 4;
+ } /* if (dctx->dStage == dstage_storeSFrameSize) */
+
+ /* case dstage_decodeSFrameSize: */ /* no direct entry */
+ { size_t const SFrameSize = LZ4F_readLE32(selectedIn);
+ dctx->frameInfo.contentSize = SFrameSize;
+ dctx->tmpInTarget = SFrameSize;
+ dctx->dStage = dstage_skipSkippable;
+ break;
+ }
+
+ case dstage_skipSkippable:
+ { size_t const skipSize = MIN(dctx->tmpInTarget, (size_t)(srcEnd-srcPtr));
+ srcPtr += skipSize;
+ dctx->tmpInTarget -= skipSize;
+ doAnotherStage = 0;
+ nextSrcSizeHint = dctx->tmpInTarget;
+ if (nextSrcSizeHint) break; /* still more to skip */
+ /* frame fully skipped : prepare context for a new frame */
+ LZ4F_resetDecompressionContext(dctx);
+ break;
+ }
+ } /* switch (dctx->dStage) */
+ } /* while (doAnotherStage) */
+
+ /* preserve history within tmpOut whenever necessary */
+ LZ4F_STATIC_ASSERT((unsigned)dstage_init == 2);
+ if ( (dctx->frameInfo.blockMode==LZ4F_blockLinked) /* next block will use up to 64KB from previous ones */
+ && (dctx->dict != dctx->tmpOutBuffer) /* dictionary is not already within tmp */
+ && (dctx->dict != NULL) /* dictionary exists */
+ && (!decompressOptionsPtr->stableDst) /* cannot rely on dst data to remain there for next call */
+ && ((unsigned)(dctx->dStage)-2 < (unsigned)(dstage_getSuffix)-2) ) /* valid stages : [init ... getSuffix[ */
+ {
+ if (dctx->dStage == dstage_flushOut) {
+ size_t const preserveSize = (size_t)(dctx->tmpOut - dctx->tmpOutBuffer);
+ size_t copySize = 64 KB - dctx->tmpOutSize;
+ const BYTE* oldDictEnd = dctx->dict + dctx->dictSize - dctx->tmpOutStart;
+ if (dctx->tmpOutSize > 64 KB) copySize = 0;
+ if (copySize > preserveSize) copySize = preserveSize;
+ assert(dctx->tmpOutBuffer != NULL);
+
+ memcpy(dctx->tmpOutBuffer + preserveSize - copySize, oldDictEnd - copySize, copySize);
+
+ dctx->dict = dctx->tmpOutBuffer;
+ dctx->dictSize = preserveSize + dctx->tmpOutStart;
+ } else {
+ const BYTE* const oldDictEnd = dctx->dict + dctx->dictSize;
+ size_t const newDictSize = MIN(dctx->dictSize, 64 KB);
+
+ memcpy(dctx->tmpOutBuffer, oldDictEnd - newDictSize, newDictSize);
+
+ dctx->dict = dctx->tmpOutBuffer;
+ dctx->dictSize = newDictSize;
+ dctx->tmpOut = dctx->tmpOutBuffer + newDictSize;
+ }
+ }
+
+ *srcSizePtr = (size_t)(srcPtr - srcStart);
+ *dstSizePtr = (size_t)(dstPtr - dstStart);
+ return nextSrcSizeHint;
+}
+
+/*! LZ4F_decompress_usingDict() :
+ * Same as LZ4F_decompress(), using a predefined dictionary.
+ * Dictionary is used "in place", without any preprocessing.
+ * It must remain accessible throughout the entire frame decoding.
+ */
+size_t LZ4F_decompress_usingDict(LZ4F_dctx* dctx,
+ void* dstBuffer, size_t* dstSizePtr,
+ const void* srcBuffer, size_t* srcSizePtr,
+ const void* dict, size_t dictSize,
+ const LZ4F_decompressOptions_t* decompressOptionsPtr)
+{
+ if (dctx->dStage <= dstage_init) {
+ dctx->dict = (const BYTE*)dict;
+ dctx->dictSize = dictSize;
+ }
+ return LZ4F_decompress(dctx, dstBuffer, dstSizePtr,
+ srcBuffer, srcSizePtr,
+ decompressOptionsPtr);
+}