lib: zstd: update to latest Linux zstd 1.5.2
Update the zstd implementation to match Linux zstd 1.5.2 from commit
2aa14b1ab2.
This was motivated by running into decompression corruption issues when
trying to uncompress files compressed with newer versions of zstd. zstd
users also claim significantly improved decompression times with newer
zstd versions which is a side benefit.
Original zstd code was copied from Linux commit 2aa14b1ab2 which is a
custom-built implementation based on zstd 1.3.1. Linux switched to an
implementation that is a copy of the upstream zstd code in Linux commit
e0c1b49f5b, this results in a large code diff. However this should make
future updates easier along with other benefits[1].
This commit is a straight mirror of the Linux zstd code, except to:
- update a few #include that do not translate cleanly
- linux/swab.h -> asm/byteorder.h
- linux/limits.h -> linux/kernel.h
- linux/module.h -> linux/compat.h
- remove assert() from debug.h so it doesn't conflict with u-boot's
assert()
- strip out the compressor code as was done in the previous u-boot zstd
- update existing zstd users to the new Linux zstd API
- change the #define for MEM_STATIC to use INLINE_KEYWORD for codesize
- add a new KConfig option that sets zstd build options to minify code
based on zstd's ZSTD_LIB_MINIFY[2].
These changes were tested by booting a zstd 1.5.2 compressed kernel inside a
FIT. And the squashfs changes by loading a file from zstd compressed squashfs
with sqfsload. buildman was used to compile test other boards and check for
binary bloat, as follows:
> $ buildman -b zstd2 --boards dh_imx6,m53menlo,mvebu_espressobin-88f3720,sandbox,sandbox64,stm32mp15_dhcom_basic,stm32mp15_dhcor_basic,turris_mox,turris_omnia -sS
> Summary of 6 commits for 9 boards (8 threads, 1 job per thread)
> 01: Merge branch '2023-01-10-platform-updates'
> arm: w+ m53menlo dh_imx6
> 02: lib: zstd: update to latest Linux zstd 1.5.2
> aarch64: (for 2/2 boards) all -3186.0 rodata +920.0 text -4106.0
> arm: (for 5/5 boards) all +1254.4 rodata +940.0 text +314.4
> sandbox: (for 2/2 boards) all -4452.0 data -16.0 rodata +640.0 text -5076.0
[1] https://github.com/torvalds/linux/commit/e0c1b49f5b674cca7b10549c53b3791d0bbc90a8
[2] https://github.com/facebook/zstd/blob/f302ad8811643c428c4e3498e28f53a0578020d3/lib/libzstd.mk#L31
Signed-off-by: Brandon Maier <brandon.maier@collins.com>
[trini: Set ret to -EINVAL for the error of "failed to detect
compressed" to fix warning, drop ZSTD_SRCSIZEHINT_MAX for non-Linux host
tool builds]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/lib/zstd/decompress/zstd_decompress.c b/lib/zstd/decompress/zstd_decompress.c
new file mode 100644
index 0000000..b9b935a
--- /dev/null
+++ b/lib/zstd/decompress/zstd_decompress.c
@@ -0,0 +1,2131 @@
+/*
+ * Copyright (c) Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+
+/* ***************************************************************
+* Tuning parameters
+*****************************************************************/
+/*!
+ * HEAPMODE :
+ * Select how default decompression function ZSTD_decompress() allocates its context,
+ * on stack (0), or into heap (1, default; requires malloc()).
+ * Note that functions with explicit context such as ZSTD_decompressDCtx() are unaffected.
+ */
+#ifndef ZSTD_HEAPMODE
+# define ZSTD_HEAPMODE 1
+#endif
+
+/*!
+* LEGACY_SUPPORT :
+* if set to 1+, ZSTD_decompress() can decode older formats (v0.1+)
+*/
+
+/*!
+ * MAXWINDOWSIZE_DEFAULT :
+ * maximum window size accepted by DStream __by default__.
+ * Frames requiring more memory will be rejected.
+ * It's possible to set a different limit using ZSTD_DCtx_setMaxWindowSize().
+ */
+#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT
+# define ZSTD_MAXWINDOWSIZE_DEFAULT (((U32)1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT) + 1)
+#endif
+
+/*!
+ * NO_FORWARD_PROGRESS_MAX :
+ * maximum allowed nb of calls to ZSTD_decompressStream()
+ * without any forward progress
+ * (defined as: no byte read from input, and no byte flushed to output)
+ * before triggering an error.
+ */
+#ifndef ZSTD_NO_FORWARD_PROGRESS_MAX
+# define ZSTD_NO_FORWARD_PROGRESS_MAX 16
+#endif
+
+
+/*-*******************************************************
+* Dependencies
+*********************************************************/
+#include "../common/zstd_deps.h" /* ZSTD_memcpy, ZSTD_memmove, ZSTD_memset */
+#include "../common/mem.h" /* low level memory routines */
+#define FSE_STATIC_LINKING_ONLY
+#include "../common/fse.h"
+#define HUF_STATIC_LINKING_ONLY
+#include "../common/huf.h"
+#include <linux/xxhash.h> /* xxh64_reset, xxh64_update, xxh64_digest, XXH64 */
+#include "../common/zstd_internal.h" /* blockProperties_t */
+#include "zstd_decompress_internal.h" /* ZSTD_DCtx */
+#include "zstd_ddict.h" /* ZSTD_DDictDictContent */
+#include "zstd_decompress_block.h" /* ZSTD_decompressBlock_internal */
+
+
+
+
+/* ***********************************
+ * Multiple DDicts Hashset internals *
+ *************************************/
+
+#define DDICT_HASHSET_MAX_LOAD_FACTOR_COUNT_MULT 4
+#define DDICT_HASHSET_MAX_LOAD_FACTOR_SIZE_MULT 3 /* These two constants represent SIZE_MULT/COUNT_MULT load factor without using a float.
+ * Currently, that means a 0.75 load factor.
+ * So, if count * COUNT_MULT / size * SIZE_MULT != 0, then we've exceeded
+ * the load factor of the ddict hash set.
+ */
+
+#define DDICT_HASHSET_TABLE_BASE_SIZE 64
+#define DDICT_HASHSET_RESIZE_FACTOR 2
+
+/* Hash function to determine starting position of dict insertion within the table
+ * Returns an index between [0, hashSet->ddictPtrTableSize]
+ */
+static size_t ZSTD_DDictHashSet_getIndex(const ZSTD_DDictHashSet* hashSet, U32 dictID) {
+ const U64 hash = xxh64(&dictID, sizeof(U32), 0);
+ /* DDict ptr table size is a multiple of 2, use size - 1 as mask to get index within [0, hashSet->ddictPtrTableSize) */
+ return hash & (hashSet->ddictPtrTableSize - 1);
+}
+
+/* Adds DDict to a hashset without resizing it.
+ * If inserting a DDict with a dictID that already exists in the set, replaces the one in the set.
+ * Returns 0 if successful, or a zstd error code if something went wrong.
+ */
+static size_t ZSTD_DDictHashSet_emplaceDDict(ZSTD_DDictHashSet* hashSet, const ZSTD_DDict* ddict) {
+ const U32 dictID = ZSTD_getDictID_fromDDict(ddict);
+ size_t idx = ZSTD_DDictHashSet_getIndex(hashSet, dictID);
+ const size_t idxRangeMask = hashSet->ddictPtrTableSize - 1;
+ RETURN_ERROR_IF(hashSet->ddictPtrCount == hashSet->ddictPtrTableSize, GENERIC, "Hash set is full!");
+ DEBUGLOG(4, "Hashed index: for dictID: %u is %zu", dictID, idx);
+ while (hashSet->ddictPtrTable[idx] != NULL) {
+ /* Replace existing ddict if inserting ddict with same dictID */
+ if (ZSTD_getDictID_fromDDict(hashSet->ddictPtrTable[idx]) == dictID) {
+ DEBUGLOG(4, "DictID already exists, replacing rather than adding");
+ hashSet->ddictPtrTable[idx] = ddict;
+ return 0;
+ }
+ idx &= idxRangeMask;
+ idx++;
+ }
+ DEBUGLOG(4, "Final idx after probing for dictID %u is: %zu", dictID, idx);
+ hashSet->ddictPtrTable[idx] = ddict;
+ hashSet->ddictPtrCount++;
+ return 0;
+}
+
+/* Expands hash table by factor of DDICT_HASHSET_RESIZE_FACTOR and
+ * rehashes all values, allocates new table, frees old table.
+ * Returns 0 on success, otherwise a zstd error code.
+ */
+static size_t ZSTD_DDictHashSet_expand(ZSTD_DDictHashSet* hashSet, ZSTD_customMem customMem) {
+ size_t newTableSize = hashSet->ddictPtrTableSize * DDICT_HASHSET_RESIZE_FACTOR;
+ const ZSTD_DDict** newTable = (const ZSTD_DDict**)ZSTD_customCalloc(sizeof(ZSTD_DDict*) * newTableSize, customMem);
+ const ZSTD_DDict** oldTable = hashSet->ddictPtrTable;
+ size_t oldTableSize = hashSet->ddictPtrTableSize;
+ size_t i;
+
+ DEBUGLOG(4, "Expanding DDict hash table! Old size: %zu new size: %zu", oldTableSize, newTableSize);
+ RETURN_ERROR_IF(!newTable, memory_allocation, "Expanded hashset allocation failed!");
+ hashSet->ddictPtrTable = newTable;
+ hashSet->ddictPtrTableSize = newTableSize;
+ hashSet->ddictPtrCount = 0;
+ for (i = 0; i < oldTableSize; ++i) {
+ if (oldTable[i] != NULL) {
+ FORWARD_IF_ERROR(ZSTD_DDictHashSet_emplaceDDict(hashSet, oldTable[i]), "");
+ }
+ }
+ ZSTD_customFree((void*)oldTable, customMem);
+ DEBUGLOG(4, "Finished re-hash");
+ return 0;
+}
+
+/* Fetches a DDict with the given dictID
+ * Returns the ZSTD_DDict* with the requested dictID. If it doesn't exist, then returns NULL.
+ */
+static const ZSTD_DDict* ZSTD_DDictHashSet_getDDict(ZSTD_DDictHashSet* hashSet, U32 dictID) {
+ size_t idx = ZSTD_DDictHashSet_getIndex(hashSet, dictID);
+ const size_t idxRangeMask = hashSet->ddictPtrTableSize - 1;
+ DEBUGLOG(4, "Hashed index: for dictID: %u is %zu", dictID, idx);
+ for (;;) {
+ size_t currDictID = ZSTD_getDictID_fromDDict(hashSet->ddictPtrTable[idx]);
+ if (currDictID == dictID || currDictID == 0) {
+ /* currDictID == 0 implies a NULL ddict entry */
+ break;
+ } else {
+ idx &= idxRangeMask; /* Goes to start of table when we reach the end */
+ idx++;
+ }
+ }
+ DEBUGLOG(4, "Final idx after probing for dictID %u is: %zu", dictID, idx);
+ return hashSet->ddictPtrTable[idx];
+}
+
+/* Allocates space for and returns a ddict hash set
+ * The hash set's ZSTD_DDict* table has all values automatically set to NULL to begin with.
+ * Returns NULL if allocation failed.
+ */
+static ZSTD_DDictHashSet* ZSTD_createDDictHashSet(ZSTD_customMem customMem) {
+ ZSTD_DDictHashSet* ret = (ZSTD_DDictHashSet*)ZSTD_customMalloc(sizeof(ZSTD_DDictHashSet), customMem);
+ DEBUGLOG(4, "Allocating new hash set");
+ if (!ret)
+ return NULL;
+ ret->ddictPtrTable = (const ZSTD_DDict**)ZSTD_customCalloc(DDICT_HASHSET_TABLE_BASE_SIZE * sizeof(ZSTD_DDict*), customMem);
+ if (!ret->ddictPtrTable) {
+ ZSTD_customFree(ret, customMem);
+ return NULL;
+ }
+ ret->ddictPtrTableSize = DDICT_HASHSET_TABLE_BASE_SIZE;
+ ret->ddictPtrCount = 0;
+ return ret;
+}
+
+/* Frees the table of ZSTD_DDict* within a hashset, then frees the hashset itself.
+ * Note: The ZSTD_DDict* within the table are NOT freed.
+ */
+static void ZSTD_freeDDictHashSet(ZSTD_DDictHashSet* hashSet, ZSTD_customMem customMem) {
+ DEBUGLOG(4, "Freeing ddict hash set");
+ if (hashSet && hashSet->ddictPtrTable) {
+ ZSTD_customFree((void*)hashSet->ddictPtrTable, customMem);
+ }
+ if (hashSet) {
+ ZSTD_customFree(hashSet, customMem);
+ }
+}
+
+/* Public function: Adds a DDict into the ZSTD_DDictHashSet, possibly triggering a resize of the hash set.
+ * Returns 0 on success, or a ZSTD error.
+ */
+static size_t ZSTD_DDictHashSet_addDDict(ZSTD_DDictHashSet* hashSet, const ZSTD_DDict* ddict, ZSTD_customMem customMem) {
+ DEBUGLOG(4, "Adding dict ID: %u to hashset with - Count: %zu Tablesize: %zu", ZSTD_getDictID_fromDDict(ddict), hashSet->ddictPtrCount, hashSet->ddictPtrTableSize);
+ if (hashSet->ddictPtrCount * DDICT_HASHSET_MAX_LOAD_FACTOR_COUNT_MULT / hashSet->ddictPtrTableSize * DDICT_HASHSET_MAX_LOAD_FACTOR_SIZE_MULT != 0) {
+ FORWARD_IF_ERROR(ZSTD_DDictHashSet_expand(hashSet, customMem), "");
+ }
+ FORWARD_IF_ERROR(ZSTD_DDictHashSet_emplaceDDict(hashSet, ddict), "");
+ return 0;
+}
+
+/*-*************************************************************
+* Context management
+***************************************************************/
+size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx)
+{
+ if (dctx==NULL) return 0; /* support sizeof NULL */
+ return sizeof(*dctx)
+ + ZSTD_sizeof_DDict(dctx->ddictLocal)
+ + dctx->inBuffSize + dctx->outBuffSize;
+}
+
+size_t ZSTD_estimateDCtxSize(void) { return sizeof(ZSTD_DCtx); }
+
+
+static size_t ZSTD_startingInputLength(ZSTD_format_e format)
+{
+ size_t const startingInputLength = ZSTD_FRAMEHEADERSIZE_PREFIX(format);
+ /* only supports formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless */
+ assert( (format == ZSTD_f_zstd1) || (format == ZSTD_f_zstd1_magicless) );
+ return startingInputLength;
+}
+
+static void ZSTD_DCtx_resetParameters(ZSTD_DCtx* dctx)
+{
+ assert(dctx->streamStage == zdss_init);
+ dctx->format = ZSTD_f_zstd1;
+ dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
+ dctx->outBufferMode = ZSTD_bm_buffered;
+ dctx->forceIgnoreChecksum = ZSTD_d_validateChecksum;
+ dctx->refMultipleDDicts = ZSTD_rmd_refSingleDDict;
+}
+
+static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx)
+{
+ dctx->staticSize = 0;
+ dctx->ddict = NULL;
+ dctx->ddictLocal = NULL;
+ dctx->dictEnd = NULL;
+ dctx->ddictIsCold = 0;
+ dctx->dictUses = ZSTD_dont_use;
+ dctx->inBuff = NULL;
+ dctx->inBuffSize = 0;
+ dctx->outBuffSize = 0;
+ dctx->streamStage = zdss_init;
+ dctx->noForwardProgress = 0;
+ dctx->oversizedDuration = 0;
+#if DYNAMIC_BMI2
+ dctx->bmi2 = ZSTD_cpuSupportsBmi2();
+#endif
+ dctx->ddictSet = NULL;
+ ZSTD_DCtx_resetParameters(dctx);
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ dctx->dictContentEndForFuzzing = NULL;
+#endif
+}
+
+ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize)
+{
+ ZSTD_DCtx* const dctx = (ZSTD_DCtx*) workspace;
+
+ if ((size_t)workspace & 7) return NULL; /* 8-aligned */
+ if (workspaceSize < sizeof(ZSTD_DCtx)) return NULL; /* minimum size */
+
+ ZSTD_initDCtx_internal(dctx);
+ dctx->staticSize = workspaceSize;
+ dctx->inBuff = (char*)(dctx+1);
+ return dctx;
+}
+
+static ZSTD_DCtx* ZSTD_createDCtx_internal(ZSTD_customMem customMem) {
+ if ((!customMem.customAlloc) ^ (!customMem.customFree)) return NULL;
+
+ { ZSTD_DCtx* const dctx = (ZSTD_DCtx*)ZSTD_customMalloc(sizeof(*dctx), customMem);
+ if (!dctx) return NULL;
+ dctx->customMem = customMem;
+ ZSTD_initDCtx_internal(dctx);
+ return dctx;
+ }
+}
+
+ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
+{
+ return ZSTD_createDCtx_internal(customMem);
+}
+
+ZSTD_DCtx* ZSTD_createDCtx(void)
+{
+ DEBUGLOG(3, "ZSTD_createDCtx");
+ return ZSTD_createDCtx_internal(ZSTD_defaultCMem);
+}
+
+static void ZSTD_clearDict(ZSTD_DCtx* dctx)
+{
+ ZSTD_freeDDict(dctx->ddictLocal);
+ dctx->ddictLocal = NULL;
+ dctx->ddict = NULL;
+ dctx->dictUses = ZSTD_dont_use;
+}
+
+size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
+{
+ if (dctx==NULL) return 0; /* support free on NULL */
+ RETURN_ERROR_IF(dctx->staticSize, memory_allocation, "not compatible with static DCtx");
+ { ZSTD_customMem const cMem = dctx->customMem;
+ ZSTD_clearDict(dctx);
+ ZSTD_customFree(dctx->inBuff, cMem);
+ dctx->inBuff = NULL;
+ if (dctx->ddictSet) {
+ ZSTD_freeDDictHashSet(dctx->ddictSet, cMem);
+ dctx->ddictSet = NULL;
+ }
+ ZSTD_customFree(dctx, cMem);
+ return 0;
+ }
+}
+
+/* no longer useful */
+void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)
+{
+ size_t const toCopy = (size_t)((char*)(&dstDCtx->inBuff) - (char*)dstDCtx);
+ ZSTD_memcpy(dstDCtx, srcDCtx, toCopy); /* no need to copy workspace */
+}
+
+/* Given a dctx with a digested frame params, re-selects the correct ZSTD_DDict based on
+ * the requested dict ID from the frame. If there exists a reference to the correct ZSTD_DDict, then
+ * accordingly sets the ddict to be used to decompress the frame.
+ *
+ * If no DDict is found, then no action is taken, and the ZSTD_DCtx::ddict remains as-is.
+ *
+ * ZSTD_d_refMultipleDDicts must be enabled for this function to be called.
+ */
+static void ZSTD_DCtx_selectFrameDDict(ZSTD_DCtx* dctx) {
+ assert(dctx->refMultipleDDicts && dctx->ddictSet);
+ DEBUGLOG(4, "Adjusting DDict based on requested dict ID from frame");
+ if (dctx->ddict) {
+ const ZSTD_DDict* frameDDict = ZSTD_DDictHashSet_getDDict(dctx->ddictSet, dctx->fParams.dictID);
+ if (frameDDict) {
+ DEBUGLOG(4, "DDict found!");
+ ZSTD_clearDict(dctx);
+ dctx->dictID = dctx->fParams.dictID;
+ dctx->ddict = frameDDict;
+ dctx->dictUses = ZSTD_use_indefinitely;
+ }
+ }
+}
+
+
+/*-*************************************************************
+ * Frame header decoding
+ ***************************************************************/
+
+/*! ZSTD_isFrame() :
+ * Tells if the content of `buffer` starts with a valid Frame Identifier.
+ * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0.
+ * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled.
+ * Note 3 : Skippable Frame Identifiers are considered valid. */
+unsigned ZSTD_isFrame(const void* buffer, size_t size)
+{
+ if (size < ZSTD_FRAMEIDSIZE) return 0;
+ { U32 const magic = MEM_readLE32(buffer);
+ if (magic == ZSTD_MAGICNUMBER) return 1;
+ if ((magic & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) return 1;
+ }
+ return 0;
+}
+
+/*! ZSTD_isSkippableFrame() :
+ * Tells if the content of `buffer` starts with a valid Frame Identifier for a skippable frame.
+ * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0.
+ */
+unsigned ZSTD_isSkippableFrame(const void* buffer, size_t size)
+{
+ if (size < ZSTD_FRAMEIDSIZE) return 0;
+ { U32 const magic = MEM_readLE32(buffer);
+ if ((magic & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) return 1;
+ }
+ return 0;
+}
+
+/* ZSTD_frameHeaderSize_internal() :
+ * srcSize must be large enough to reach header size fields.
+ * note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless.
+ * @return : size of the Frame Header
+ * or an error code, which can be tested with ZSTD_isError() */
+static size_t ZSTD_frameHeaderSize_internal(const void* src, size_t srcSize, ZSTD_format_e format)
+{
+ size_t const minInputSize = ZSTD_startingInputLength(format);
+ RETURN_ERROR_IF(srcSize < minInputSize, srcSize_wrong, "");
+
+ { BYTE const fhd = ((const BYTE*)src)[minInputSize-1];
+ U32 const dictID= fhd & 3;
+ U32 const singleSegment = (fhd >> 5) & 1;
+ U32 const fcsId = fhd >> 6;
+ return minInputSize + !singleSegment
+ + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId]
+ + (singleSegment && !fcsId);
+ }
+}
+
+/* ZSTD_frameHeaderSize() :
+ * srcSize must be >= ZSTD_frameHeaderSize_prefix.
+ * @return : size of the Frame Header,
+ * or an error code (if srcSize is too small) */
+size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
+{
+ return ZSTD_frameHeaderSize_internal(src, srcSize, ZSTD_f_zstd1);
+}
+
+
+/* ZSTD_getFrameHeader_advanced() :
+ * decode Frame Header, or require larger `srcSize`.
+ * note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless
+ * @return : 0, `zfhPtr` is correctly filled,
+ * >0, `srcSize` is too small, value is wanted `srcSize` amount,
+ * or an error code, which can be tested using ZSTD_isError() */
+size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format)
+{
+ const BYTE* ip = (const BYTE*)src;
+ size_t const minInputSize = ZSTD_startingInputLength(format);
+
+ ZSTD_memset(zfhPtr, 0, sizeof(*zfhPtr)); /* not strictly necessary, but static analyzer do not understand that zfhPtr is only going to be read only if return value is zero, since they are 2 different signals */
+ if (srcSize < minInputSize) return minInputSize;
+ RETURN_ERROR_IF(src==NULL, GENERIC, "invalid parameter");
+
+ if ( (format != ZSTD_f_zstd1_magicless)
+ && (MEM_readLE32(src) != ZSTD_MAGICNUMBER) ) {
+ if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
+ /* skippable frame */
+ if (srcSize < ZSTD_SKIPPABLEHEADERSIZE)
+ return ZSTD_SKIPPABLEHEADERSIZE; /* magic number + frame length */
+ ZSTD_memset(zfhPtr, 0, sizeof(*zfhPtr));
+ zfhPtr->frameContentSize = MEM_readLE32((const char *)src + ZSTD_FRAMEIDSIZE);
+ zfhPtr->frameType = ZSTD_skippableFrame;
+ return 0;
+ }
+ RETURN_ERROR(prefix_unknown, "");
+ }
+
+ /* ensure there is enough `srcSize` to fully read/decode frame header */
+ { size_t const fhsize = ZSTD_frameHeaderSize_internal(src, srcSize, format);
+ if (srcSize < fhsize) return fhsize;
+ zfhPtr->headerSize = (U32)fhsize;
+ }
+
+ { BYTE const fhdByte = ip[minInputSize-1];
+ size_t pos = minInputSize;
+ U32 const dictIDSizeCode = fhdByte&3;
+ U32 const checksumFlag = (fhdByte>>2)&1;
+ U32 const singleSegment = (fhdByte>>5)&1;
+ U32 const fcsID = fhdByte>>6;
+ U64 windowSize = 0;
+ U32 dictID = 0;
+ U64 frameContentSize = ZSTD_CONTENTSIZE_UNKNOWN;
+ RETURN_ERROR_IF((fhdByte & 0x08) != 0, frameParameter_unsupported,
+ "reserved bits, must be zero");
+
+ if (!singleSegment) {
+ BYTE const wlByte = ip[pos++];
+ U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
+ RETURN_ERROR_IF(windowLog > ZSTD_WINDOWLOG_MAX, frameParameter_windowTooLarge, "");
+ windowSize = (1ULL << windowLog);
+ windowSize += (windowSize >> 3) * (wlByte&7);
+ }
+ switch(dictIDSizeCode)
+ {
+ default:
+ assert(0); /* impossible */
+ ZSTD_FALLTHROUGH;
+ case 0 : break;
+ case 1 : dictID = ip[pos]; pos++; break;
+ case 2 : dictID = MEM_readLE16(ip+pos); pos+=2; break;
+ case 3 : dictID = MEM_readLE32(ip+pos); pos+=4; break;
+ }
+ switch(fcsID)
+ {
+ default:
+ assert(0); /* impossible */
+ ZSTD_FALLTHROUGH;
+ case 0 : if (singleSegment) frameContentSize = ip[pos]; break;
+ case 1 : frameContentSize = MEM_readLE16(ip+pos)+256; break;
+ case 2 : frameContentSize = MEM_readLE32(ip+pos); break;
+ case 3 : frameContentSize = MEM_readLE64(ip+pos); break;
+ }
+ if (singleSegment) windowSize = frameContentSize;
+
+ zfhPtr->frameType = ZSTD_frame;
+ zfhPtr->frameContentSize = frameContentSize;
+ zfhPtr->windowSize = windowSize;
+ zfhPtr->blockSizeMax = (unsigned) MIN(windowSize, ZSTD_BLOCKSIZE_MAX);
+ zfhPtr->dictID = dictID;
+ zfhPtr->checksumFlag = checksumFlag;
+ }
+ return 0;
+}
+
+/* ZSTD_getFrameHeader() :
+ * decode Frame Header, or require larger `srcSize`.
+ * note : this function does not consume input, it only reads it.
+ * @return : 0, `zfhPtr` is correctly filled,
+ * >0, `srcSize` is too small, value is wanted `srcSize` amount,
+ * or an error code, which can be tested using ZSTD_isError() */
+size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize)
+{
+ return ZSTD_getFrameHeader_advanced(zfhPtr, src, srcSize, ZSTD_f_zstd1);
+}
+
+/* ZSTD_getFrameContentSize() :
+ * compatible with legacy mode
+ * @return : decompressed size of the single frame pointed to be `src` if known, otherwise
+ * - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
+ * - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */
+unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize)
+{
+ { ZSTD_frameHeader zfh;
+ if (ZSTD_getFrameHeader(&zfh, src, srcSize) != 0)
+ return ZSTD_CONTENTSIZE_ERROR;
+ if (zfh.frameType == ZSTD_skippableFrame) {
+ return 0;
+ } else {
+ return zfh.frameContentSize;
+ } }
+}
+
+static size_t readSkippableFrameSize(void const* src, size_t srcSize)
+{
+ size_t const skippableHeaderSize = ZSTD_SKIPPABLEHEADERSIZE;
+ U32 sizeU32;
+
+ RETURN_ERROR_IF(srcSize < ZSTD_SKIPPABLEHEADERSIZE, srcSize_wrong, "");
+
+ sizeU32 = MEM_readLE32((BYTE const*)src + ZSTD_FRAMEIDSIZE);
+ RETURN_ERROR_IF((U32)(sizeU32 + ZSTD_SKIPPABLEHEADERSIZE) < sizeU32,
+ frameParameter_unsupported, "");
+ {
+ size_t const skippableSize = skippableHeaderSize + sizeU32;
+ RETURN_ERROR_IF(skippableSize > srcSize, srcSize_wrong, "");
+ return skippableSize;
+ }
+}
+
+/*! ZSTD_readSkippableFrame() :
+ * Retrieves a zstd skippable frame containing data given by src, and writes it to dst buffer.
+ *
+ * The parameter magicVariant will receive the magicVariant that was supplied when the frame was written,
+ * i.e. magicNumber - ZSTD_MAGIC_SKIPPABLE_START. This can be NULL if the caller is not interested
+ * in the magicVariant.
+ *
+ * Returns an error if destination buffer is not large enough, or if the frame is not skippable.
+ *
+ * @return : number of bytes written or a ZSTD error.
+ */
+ZSTDLIB_API size_t ZSTD_readSkippableFrame(void* dst, size_t dstCapacity, unsigned* magicVariant,
+ const void* src, size_t srcSize)
+{
+ U32 const magicNumber = MEM_readLE32(src);
+ size_t skippableFrameSize = readSkippableFrameSize(src, srcSize);
+ size_t skippableContentSize = skippableFrameSize - ZSTD_SKIPPABLEHEADERSIZE;
+
+ /* check input validity */
+ RETURN_ERROR_IF(!ZSTD_isSkippableFrame(src, srcSize), frameParameter_unsupported, "");
+ RETURN_ERROR_IF(skippableFrameSize < ZSTD_SKIPPABLEHEADERSIZE || skippableFrameSize > srcSize, srcSize_wrong, "");
+ RETURN_ERROR_IF(skippableContentSize > dstCapacity, dstSize_tooSmall, "");
+
+ /* deliver payload */
+ if (skippableContentSize > 0 && dst != NULL)
+ ZSTD_memcpy(dst, (const BYTE *)src + ZSTD_SKIPPABLEHEADERSIZE, skippableContentSize);
+ if (magicVariant != NULL)
+ *magicVariant = magicNumber - ZSTD_MAGIC_SKIPPABLE_START;
+ return skippableContentSize;
+}
+
+/* ZSTD_findDecompressedSize() :
+ * compatible with legacy mode
+ * `srcSize` must be the exact length of some number of ZSTD compressed and/or
+ * skippable frames
+ * @return : decompressed size of the frames contained */
+unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize)
+{
+ unsigned long long totalDstSize = 0;
+
+ while (srcSize >= ZSTD_startingInputLength(ZSTD_f_zstd1)) {
+ U32 const magicNumber = MEM_readLE32(src);
+
+ if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
+ size_t const skippableSize = readSkippableFrameSize(src, srcSize);
+ if (ZSTD_isError(skippableSize)) {
+ return ZSTD_CONTENTSIZE_ERROR;
+ }
+ assert(skippableSize <= srcSize);
+
+ src = (const BYTE *)src + skippableSize;
+ srcSize -= skippableSize;
+ continue;
+ }
+
+ { unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
+ if (ret >= ZSTD_CONTENTSIZE_ERROR) return ret;
+
+ /* check for overflow */
+ if (totalDstSize + ret < totalDstSize) return ZSTD_CONTENTSIZE_ERROR;
+ totalDstSize += ret;
+ }
+ { size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize);
+ if (ZSTD_isError(frameSrcSize)) {
+ return ZSTD_CONTENTSIZE_ERROR;
+ }
+
+ src = (const BYTE *)src + frameSrcSize;
+ srcSize -= frameSrcSize;
+ }
+ } /* while (srcSize >= ZSTD_frameHeaderSize_prefix) */
+
+ if (srcSize) return ZSTD_CONTENTSIZE_ERROR;
+
+ return totalDstSize;
+}
+
+/* ZSTD_getDecompressedSize() :
+ * compatible with legacy mode
+ * @return : decompressed size if known, 0 otherwise
+ note : 0 can mean any of the following :
+ - frame content is empty
+ - decompressed size field is not present in frame header
+ - frame header unknown / not supported
+ - frame header not complete (`srcSize` too small) */
+unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize)
+{
+ unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
+ ZSTD_STATIC_ASSERT(ZSTD_CONTENTSIZE_ERROR < ZSTD_CONTENTSIZE_UNKNOWN);
+ return (ret >= ZSTD_CONTENTSIZE_ERROR) ? 0 : ret;
+}
+
+
+/* ZSTD_decodeFrameHeader() :
+ * `headerSize` must be the size provided by ZSTD_frameHeaderSize().
+ * If multiple DDict references are enabled, also will choose the correct DDict to use.
+ * @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */
+static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx* dctx, const void* src, size_t headerSize)
+{
+ size_t const result = ZSTD_getFrameHeader_advanced(&(dctx->fParams), src, headerSize, dctx->format);
+ if (ZSTD_isError(result)) return result; /* invalid header */
+ RETURN_ERROR_IF(result>0, srcSize_wrong, "headerSize too small");
+
+ /* Reference DDict requested by frame if dctx references multiple ddicts */
+ if (dctx->refMultipleDDicts == ZSTD_rmd_refMultipleDDicts && dctx->ddictSet) {
+ ZSTD_DCtx_selectFrameDDict(dctx);
+ }
+
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ /* Skip the dictID check in fuzzing mode, because it makes the search
+ * harder.
+ */
+ RETURN_ERROR_IF(dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID),
+ dictionary_wrong, "");
+#endif
+ dctx->validateChecksum = (dctx->fParams.checksumFlag && !dctx->forceIgnoreChecksum) ? 1 : 0;
+ if (dctx->validateChecksum) xxh64_reset(&dctx->xxhState, 0);
+ dctx->processedCSize += headerSize;
+ return 0;
+}
+
+static ZSTD_frameSizeInfo ZSTD_errorFrameSizeInfo(size_t ret)
+{
+ ZSTD_frameSizeInfo frameSizeInfo;
+ frameSizeInfo.compressedSize = ret;
+ frameSizeInfo.decompressedBound = ZSTD_CONTENTSIZE_ERROR;
+ return frameSizeInfo;
+}
+
+static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize)
+{
+ ZSTD_frameSizeInfo frameSizeInfo;
+ ZSTD_memset(&frameSizeInfo, 0, sizeof(ZSTD_frameSizeInfo));
+
+
+ if ((srcSize >= ZSTD_SKIPPABLEHEADERSIZE)
+ && (MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
+ frameSizeInfo.compressedSize = readSkippableFrameSize(src, srcSize);
+ assert(ZSTD_isError(frameSizeInfo.compressedSize) ||
+ frameSizeInfo.compressedSize <= srcSize);
+ return frameSizeInfo;
+ } else {
+ const BYTE* ip = (const BYTE*)src;
+ const BYTE* const ipstart = ip;
+ size_t remainingSize = srcSize;
+ size_t nbBlocks = 0;
+ ZSTD_frameHeader zfh;
+
+ /* Extract Frame Header */
+ { size_t const ret = ZSTD_getFrameHeader(&zfh, src, srcSize);
+ if (ZSTD_isError(ret))
+ return ZSTD_errorFrameSizeInfo(ret);
+ if (ret > 0)
+ return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong));
+ }
+
+ ip += zfh.headerSize;
+ remainingSize -= zfh.headerSize;
+
+ /* Iterate over each block */
+ while (1) {
+ blockProperties_t blockProperties;
+ size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
+ if (ZSTD_isError(cBlockSize))
+ return ZSTD_errorFrameSizeInfo(cBlockSize);
+
+ if (ZSTD_blockHeaderSize + cBlockSize > remainingSize)
+ return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong));
+
+ ip += ZSTD_blockHeaderSize + cBlockSize;
+ remainingSize -= ZSTD_blockHeaderSize + cBlockSize;
+ nbBlocks++;
+
+ if (blockProperties.lastBlock) break;
+ }
+
+ /* Final frame content checksum */
+ if (zfh.checksumFlag) {
+ if (remainingSize < 4)
+ return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong));
+ ip += 4;
+ }
+
+ frameSizeInfo.compressedSize = (size_t)(ip - ipstart);
+ frameSizeInfo.decompressedBound = (zfh.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN)
+ ? zfh.frameContentSize
+ : nbBlocks * zfh.blockSizeMax;
+ return frameSizeInfo;
+ }
+}
+
+/* ZSTD_findFrameCompressedSize() :
+ * compatible with legacy mode
+ * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame
+ * `srcSize` must be at least as large as the frame contained
+ * @return : the compressed size of the frame starting at `src` */
+size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize)
+{
+ ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize);
+ return frameSizeInfo.compressedSize;
+}
+
+/* ZSTD_decompressBound() :
+ * compatible with legacy mode
+ * `src` must point to the start of a ZSTD frame or a skippeable frame
+ * `srcSize` must be at least as large as the frame contained
+ * @return : the maximum decompressed size of the compressed source
+ */
+unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize)
+{
+ unsigned long long bound = 0;
+ /* Iterate over each frame */
+ while (srcSize > 0) {
+ ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize);
+ size_t const compressedSize = frameSizeInfo.compressedSize;
+ unsigned long long const decompressedBound = frameSizeInfo.decompressedBound;
+ if (ZSTD_isError(compressedSize) || decompressedBound == ZSTD_CONTENTSIZE_ERROR)
+ return ZSTD_CONTENTSIZE_ERROR;
+ assert(srcSize >= compressedSize);
+ src = (const BYTE*)src + compressedSize;
+ srcSize -= compressedSize;
+ bound += decompressedBound;
+ }
+ return bound;
+}
+
+
+/*-*************************************************************
+ * Frame decoding
+ ***************************************************************/
+
+/* ZSTD_insertBlock() :
+ * insert `src` block into `dctx` history. Useful to track uncompressed blocks. */
+size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize)
+{
+ DEBUGLOG(5, "ZSTD_insertBlock: %u bytes", (unsigned)blockSize);
+ ZSTD_checkContinuity(dctx, blockStart, blockSize);
+ dctx->previousDstEnd = (const char*)blockStart + blockSize;
+ return blockSize;
+}
+
+
+static size_t ZSTD_copyRawBlock(void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize)
+{
+ DEBUGLOG(5, "ZSTD_copyRawBlock");
+ RETURN_ERROR_IF(srcSize > dstCapacity, dstSize_tooSmall, "");
+ if (dst == NULL) {
+ if (srcSize == 0) return 0;
+ RETURN_ERROR(dstBuffer_null, "");
+ }
+ ZSTD_memcpy(dst, src, srcSize);
+ return srcSize;
+}
+
+static size_t ZSTD_setRleBlock(void* dst, size_t dstCapacity,
+ BYTE b,
+ size_t regenSize)
+{
+ RETURN_ERROR_IF(regenSize > dstCapacity, dstSize_tooSmall, "");
+ if (dst == NULL) {
+ if (regenSize == 0) return 0;
+ RETURN_ERROR(dstBuffer_null, "");
+ }
+ ZSTD_memset(dst, b, regenSize);
+ return regenSize;
+}
+
+static void ZSTD_DCtx_trace_end(ZSTD_DCtx const* dctx, U64 uncompressedSize, U64 compressedSize, unsigned streaming)
+{
+ (void)dctx;
+ (void)uncompressedSize;
+ (void)compressedSize;
+ (void)streaming;
+}
+
+
+/*! ZSTD_decompressFrame() :
+ * @dctx must be properly initialized
+ * will update *srcPtr and *srcSizePtr,
+ * to make *srcPtr progress by one frame. */
+static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void** srcPtr, size_t *srcSizePtr)
+{
+ const BYTE* const istart = (const BYTE*)(*srcPtr);
+ const BYTE* ip = istart;
+ BYTE* const ostart = (BYTE*)dst;
+ BYTE* const oend = dstCapacity != 0 ? ostart + dstCapacity : ostart;
+ BYTE* op = ostart;
+ size_t remainingSrcSize = *srcSizePtr;
+
+ DEBUGLOG(4, "ZSTD_decompressFrame (srcSize:%i)", (int)*srcSizePtr);
+
+ /* check */
+ RETURN_ERROR_IF(
+ remainingSrcSize < ZSTD_FRAMEHEADERSIZE_MIN(dctx->format)+ZSTD_blockHeaderSize,
+ srcSize_wrong, "");
+
+ /* Frame Header */
+ { size_t const frameHeaderSize = ZSTD_frameHeaderSize_internal(
+ ip, ZSTD_FRAMEHEADERSIZE_PREFIX(dctx->format), dctx->format);
+ if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
+ RETURN_ERROR_IF(remainingSrcSize < frameHeaderSize+ZSTD_blockHeaderSize,
+ srcSize_wrong, "");
+ FORWARD_IF_ERROR( ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize) , "");
+ ip += frameHeaderSize; remainingSrcSize -= frameHeaderSize;
+ }
+
+ /* Loop on each block */
+ while (1) {
+ size_t decodedSize;
+ blockProperties_t blockProperties;
+ size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSrcSize, &blockProperties);
+ if (ZSTD_isError(cBlockSize)) return cBlockSize;
+
+ ip += ZSTD_blockHeaderSize;
+ remainingSrcSize -= ZSTD_blockHeaderSize;
+ RETURN_ERROR_IF(cBlockSize > remainingSrcSize, srcSize_wrong, "");
+
+ switch(blockProperties.blockType)
+ {
+ case bt_compressed:
+ decodedSize = ZSTD_decompressBlock_internal(dctx, op, (size_t)(oend-op), ip, cBlockSize, /* frame */ 1, not_streaming);
+ break;
+ case bt_raw :
+ decodedSize = ZSTD_copyRawBlock(op, (size_t)(oend-op), ip, cBlockSize);
+ break;
+ case bt_rle :
+ decodedSize = ZSTD_setRleBlock(op, (size_t)(oend-op), *ip, blockProperties.origSize);
+ break;
+ case bt_reserved :
+ default:
+ RETURN_ERROR(corruption_detected, "invalid block type");
+ }
+
+ if (ZSTD_isError(decodedSize)) return decodedSize;
+ if (dctx->validateChecksum)
+ xxh64_update(&dctx->xxhState, op, decodedSize);
+ if (decodedSize != 0)
+ op += decodedSize;
+ assert(ip != NULL);
+ ip += cBlockSize;
+ remainingSrcSize -= cBlockSize;
+ if (blockProperties.lastBlock) break;
+ }
+
+ if (dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN) {
+ RETURN_ERROR_IF((U64)(op-ostart) != dctx->fParams.frameContentSize,
+ corruption_detected, "");
+ }
+ if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */
+ RETURN_ERROR_IF(remainingSrcSize<4, checksum_wrong, "");
+ if (!dctx->forceIgnoreChecksum) {
+ U32 const checkCalc = (U32)xxh64_digest(&dctx->xxhState);
+ U32 checkRead;
+ checkRead = MEM_readLE32(ip);
+ RETURN_ERROR_IF(checkRead != checkCalc, checksum_wrong, "");
+ }
+ ip += 4;
+ remainingSrcSize -= 4;
+ }
+ ZSTD_DCtx_trace_end(dctx, (U64)(op-ostart), (U64)(ip-istart), /* streaming */ 0);
+ /* Allow caller to get size read */
+ *srcPtr = ip;
+ *srcSizePtr = remainingSrcSize;
+ return (size_t)(op-ostart);
+}
+
+static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const void* dict, size_t dictSize,
+ const ZSTD_DDict* ddict)
+{
+ void* const dststart = dst;
+ int moreThan1Frame = 0;
+
+ DEBUGLOG(5, "ZSTD_decompressMultiFrame");
+ assert(dict==NULL || ddict==NULL); /* either dict or ddict set, not both */
+
+ if (ddict) {
+ dict = ZSTD_DDict_dictContent(ddict);
+ dictSize = ZSTD_DDict_dictSize(ddict);
+ }
+
+ while (srcSize >= ZSTD_startingInputLength(dctx->format)) {
+
+
+ { U32 const magicNumber = MEM_readLE32(src);
+ DEBUGLOG(4, "reading magic number %08X (expecting %08X)",
+ (unsigned)magicNumber, ZSTD_MAGICNUMBER);
+ if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) {
+ size_t const skippableSize = readSkippableFrameSize(src, srcSize);
+ FORWARD_IF_ERROR(skippableSize, "readSkippableFrameSize failed");
+ assert(skippableSize <= srcSize);
+
+ src = (const BYTE *)src + skippableSize;
+ srcSize -= skippableSize;
+ continue;
+ } }
+
+ if (ddict) {
+ /* we were called from ZSTD_decompress_usingDDict */
+ FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(dctx, ddict), "");
+ } else {
+ /* this will initialize correctly with no dict if dict == NULL, so
+ * use this in all cases but ddict */
+ FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize), "");
+ }
+ ZSTD_checkContinuity(dctx, dst, dstCapacity);
+
+ { const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity,
+ &src, &srcSize);
+ RETURN_ERROR_IF(
+ (ZSTD_getErrorCode(res) == ZSTD_error_prefix_unknown)
+ && (moreThan1Frame==1),
+ srcSize_wrong,
+ "At least one frame successfully completed, "
+ "but following bytes are garbage: "
+ "it's more likely to be a srcSize error, "
+ "specifying more input bytes than size of frame(s). "
+ "Note: one could be unlucky, it might be a corruption error instead, "
+ "happening right at the place where we expect zstd magic bytes. "
+ "But this is _much_ less likely than a srcSize field error.");
+ if (ZSTD_isError(res)) return res;
+ assert(res <= dstCapacity);
+ if (res != 0)
+ dst = (BYTE*)dst + res;
+ dstCapacity -= res;
+ }
+ moreThan1Frame = 1;
+ } /* while (srcSize >= ZSTD_frameHeaderSize_prefix) */
+
+ RETURN_ERROR_IF(srcSize, srcSize_wrong, "input not entirely consumed");
+
+ return (size_t)((BYTE*)dst - (BYTE*)dststart);
+}
+
+size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const void* dict, size_t dictSize)
+{
+ return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, dict, dictSize, NULL);
+}
+
+
+static ZSTD_DDict const* ZSTD_getDDict(ZSTD_DCtx* dctx)
+{
+ switch (dctx->dictUses) {
+ default:
+ assert(0 /* Impossible */);
+ ZSTD_FALLTHROUGH;
+ case ZSTD_dont_use:
+ ZSTD_clearDict(dctx);
+ return NULL;
+ case ZSTD_use_indefinitely:
+ return dctx->ddict;
+ case ZSTD_use_once:
+ dctx->dictUses = ZSTD_dont_use;
+ return dctx->ddict;
+ }
+}
+
+size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
+{
+ return ZSTD_decompress_usingDDict(dctx, dst, dstCapacity, src, srcSize, ZSTD_getDDict(dctx));
+}
+
+
+size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
+{
+#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE>=1)
+ size_t regenSize;
+ ZSTD_DCtx* const dctx = ZSTD_createDCtx_internal(ZSTD_defaultCMem);
+ RETURN_ERROR_IF(dctx==NULL, memory_allocation, "NULL pointer!");
+ regenSize = ZSTD_decompressDCtx(dctx, dst, dstCapacity, src, srcSize);
+ ZSTD_freeDCtx(dctx);
+ return regenSize;
+#else /* stack mode */
+ ZSTD_DCtx dctx;
+ ZSTD_initDCtx_internal(&dctx);
+ return ZSTD_decompressDCtx(&dctx, dst, dstCapacity, src, srcSize);
+#endif
+}
+
+
+/*-**************************************
+* Advanced Streaming Decompression API
+* Bufferless and synchronous
+****************************************/
+size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx) { return dctx->expected; }
+
+/*
+ * Similar to ZSTD_nextSrcSizeToDecompress(), but when a block input can be streamed,
+ * we allow taking a partial block as the input. Currently only raw uncompressed blocks can
+ * be streamed.
+ *
+ * For blocks that can be streamed, this allows us to reduce the latency until we produce
+ * output, and avoid copying the input.
+ *
+ * @param inputSize - The total amount of input that the caller currently has.
+ */
+static size_t ZSTD_nextSrcSizeToDecompressWithInputSize(ZSTD_DCtx* dctx, size_t inputSize) {
+ if (!(dctx->stage == ZSTDds_decompressBlock || dctx->stage == ZSTDds_decompressLastBlock))
+ return dctx->expected;
+ if (dctx->bType != bt_raw)
+ return dctx->expected;
+ return BOUNDED(1, inputSize, dctx->expected);
+}
+
+ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
+ switch(dctx->stage)
+ {
+ default: /* should not happen */
+ assert(0);
+ ZSTD_FALLTHROUGH;
+ case ZSTDds_getFrameHeaderSize:
+ ZSTD_FALLTHROUGH;
+ case ZSTDds_decodeFrameHeader:
+ return ZSTDnit_frameHeader;
+ case ZSTDds_decodeBlockHeader:
+ return ZSTDnit_blockHeader;
+ case ZSTDds_decompressBlock:
+ return ZSTDnit_block;
+ case ZSTDds_decompressLastBlock:
+ return ZSTDnit_lastBlock;
+ case ZSTDds_checkChecksum:
+ return ZSTDnit_checksum;
+ case ZSTDds_decodeSkippableHeader:
+ ZSTD_FALLTHROUGH;
+ case ZSTDds_skipFrame:
+ return ZSTDnit_skippableFrame;
+ }
+}
+
+static int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skipFrame; }
+
+/* ZSTD_decompressContinue() :
+ * srcSize : must be the exact nb of bytes expected (see ZSTD_nextSrcSizeToDecompress())
+ * @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity)
+ * or an error code, which can be tested using ZSTD_isError() */
+size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
+{
+ DEBUGLOG(5, "ZSTD_decompressContinue (srcSize:%u)", (unsigned)srcSize);
+ /* Sanity check */
+ RETURN_ERROR_IF(srcSize != ZSTD_nextSrcSizeToDecompressWithInputSize(dctx, srcSize), srcSize_wrong, "not allowed");
+ ZSTD_checkContinuity(dctx, dst, dstCapacity);
+
+ dctx->processedCSize += srcSize;
+
+ switch (dctx->stage)
+ {
+ case ZSTDds_getFrameHeaderSize :
+ assert(src != NULL);
+ if (dctx->format == ZSTD_f_zstd1) { /* allows header */
+ assert(srcSize >= ZSTD_FRAMEIDSIZE); /* to read skippable magic number */
+ if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
+ ZSTD_memcpy(dctx->headerBuffer, src, srcSize);
+ dctx->expected = ZSTD_SKIPPABLEHEADERSIZE - srcSize; /* remaining to load to get full skippable frame header */
+ dctx->stage = ZSTDds_decodeSkippableHeader;
+ return 0;
+ } }
+ dctx->headerSize = ZSTD_frameHeaderSize_internal(src, srcSize, dctx->format);
+ if (ZSTD_isError(dctx->headerSize)) return dctx->headerSize;
+ ZSTD_memcpy(dctx->headerBuffer, src, srcSize);
+ dctx->expected = dctx->headerSize - srcSize;
+ dctx->stage = ZSTDds_decodeFrameHeader;
+ return 0;
+
+ case ZSTDds_decodeFrameHeader:
+ assert(src != NULL);
+ ZSTD_memcpy(dctx->headerBuffer + (dctx->headerSize - srcSize), src, srcSize);
+ FORWARD_IF_ERROR(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize), "");
+ dctx->expected = ZSTD_blockHeaderSize;
+ dctx->stage = ZSTDds_decodeBlockHeader;
+ return 0;
+
+ case ZSTDds_decodeBlockHeader:
+ { blockProperties_t bp;
+ size_t const cBlockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp);
+ if (ZSTD_isError(cBlockSize)) return cBlockSize;
+ RETURN_ERROR_IF(cBlockSize > dctx->fParams.blockSizeMax, corruption_detected, "Block Size Exceeds Maximum");
+ dctx->expected = cBlockSize;
+ dctx->bType = bp.blockType;
+ dctx->rleSize = bp.origSize;
+ if (cBlockSize) {
+ dctx->stage = bp.lastBlock ? ZSTDds_decompressLastBlock : ZSTDds_decompressBlock;
+ return 0;
+ }
+ /* empty block */
+ if (bp.lastBlock) {
+ if (dctx->fParams.checksumFlag) {
+ dctx->expected = 4;
+ dctx->stage = ZSTDds_checkChecksum;
+ } else {
+ dctx->expected = 0; /* end of frame */
+ dctx->stage = ZSTDds_getFrameHeaderSize;
+ }
+ } else {
+ dctx->expected = ZSTD_blockHeaderSize; /* jump to next header */
+ dctx->stage = ZSTDds_decodeBlockHeader;
+ }
+ return 0;
+ }
+
+ case ZSTDds_decompressLastBlock:
+ case ZSTDds_decompressBlock:
+ DEBUGLOG(5, "ZSTD_decompressContinue: case ZSTDds_decompressBlock");
+ { size_t rSize;
+ switch(dctx->bType)
+ {
+ case bt_compressed:
+ DEBUGLOG(5, "ZSTD_decompressContinue: case bt_compressed");
+ rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 1, is_streaming);
+ dctx->expected = 0; /* Streaming not supported */
+ break;
+ case bt_raw :
+ assert(srcSize <= dctx->expected);
+ rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize);
+ FORWARD_IF_ERROR(rSize, "ZSTD_copyRawBlock failed");
+ assert(rSize == srcSize);
+ dctx->expected -= rSize;
+ break;
+ case bt_rle :
+ rSize = ZSTD_setRleBlock(dst, dstCapacity, *(const BYTE*)src, dctx->rleSize);
+ dctx->expected = 0; /* Streaming not supported */
+ break;
+ case bt_reserved : /* should never happen */
+ default:
+ RETURN_ERROR(corruption_detected, "invalid block type");
+ }
+ FORWARD_IF_ERROR(rSize, "");
+ RETURN_ERROR_IF(rSize > dctx->fParams.blockSizeMax, corruption_detected, "Decompressed Block Size Exceeds Maximum");
+ DEBUGLOG(5, "ZSTD_decompressContinue: decoded size from block : %u", (unsigned)rSize);
+ dctx->decodedSize += rSize;
+ if (dctx->validateChecksum) xxh64_update(&dctx->xxhState, dst, rSize);
+ dctx->previousDstEnd = (char*)dst + rSize;
+
+ /* Stay on the same stage until we are finished streaming the block. */
+ if (dctx->expected > 0) {
+ return rSize;
+ }
+
+ if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */
+ DEBUGLOG(4, "ZSTD_decompressContinue: decoded size from frame : %u", (unsigned)dctx->decodedSize);
+ RETURN_ERROR_IF(
+ dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN
+ && dctx->decodedSize != dctx->fParams.frameContentSize,
+ corruption_detected, "");
+ if (dctx->fParams.checksumFlag) { /* another round for frame checksum */
+ dctx->expected = 4;
+ dctx->stage = ZSTDds_checkChecksum;
+ } else {
+ ZSTD_DCtx_trace_end(dctx, dctx->decodedSize, dctx->processedCSize, /* streaming */ 1);
+ dctx->expected = 0; /* ends here */
+ dctx->stage = ZSTDds_getFrameHeaderSize;
+ }
+ } else {
+ dctx->stage = ZSTDds_decodeBlockHeader;
+ dctx->expected = ZSTD_blockHeaderSize;
+ }
+ return rSize;
+ }
+
+ case ZSTDds_checkChecksum:
+ assert(srcSize == 4); /* guaranteed by dctx->expected */
+ {
+ if (dctx->validateChecksum) {
+ U32 const h32 = (U32)xxh64_digest(&dctx->xxhState);
+ U32 const check32 = MEM_readLE32(src);
+ DEBUGLOG(4, "ZSTD_decompressContinue: checksum : calculated %08X :: %08X read", (unsigned)h32, (unsigned)check32);
+ RETURN_ERROR_IF(check32 != h32, checksum_wrong, "");
+ }
+ ZSTD_DCtx_trace_end(dctx, dctx->decodedSize, dctx->processedCSize, /* streaming */ 1);
+ dctx->expected = 0;
+ dctx->stage = ZSTDds_getFrameHeaderSize;
+ return 0;
+ }
+
+ case ZSTDds_decodeSkippableHeader:
+ assert(src != NULL);
+ assert(srcSize <= ZSTD_SKIPPABLEHEADERSIZE);
+ ZSTD_memcpy(dctx->headerBuffer + (ZSTD_SKIPPABLEHEADERSIZE - srcSize), src, srcSize); /* complete skippable header */
+ dctx->expected = MEM_readLE32(dctx->headerBuffer + ZSTD_FRAMEIDSIZE); /* note : dctx->expected can grow seriously large, beyond local buffer size */
+ dctx->stage = ZSTDds_skipFrame;
+ return 0;
+
+ case ZSTDds_skipFrame:
+ dctx->expected = 0;
+ dctx->stage = ZSTDds_getFrameHeaderSize;
+ return 0;
+
+ default:
+ assert(0); /* impossible */
+ RETURN_ERROR(GENERIC, "impossible to reach"); /* some compiler require default to do something */
+ }
+}
+
+
+static size_t ZSTD_refDictContent(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
+{
+ dctx->dictEnd = dctx->previousDstEnd;
+ dctx->virtualStart = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->prefixStart));
+ dctx->prefixStart = dict;
+ dctx->previousDstEnd = (const char*)dict + dictSize;
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ dctx->dictContentBeginForFuzzing = dctx->prefixStart;
+ dctx->dictContentEndForFuzzing = dctx->previousDstEnd;
+#endif
+ return 0;
+}
+
+/*! ZSTD_loadDEntropy() :
+ * dict : must point at beginning of a valid zstd dictionary.
+ * @return : size of entropy tables read */
+size_t
+ZSTD_loadDEntropy(ZSTD_entropyDTables_t* entropy,
+ const void* const dict, size_t const dictSize)
+{
+ const BYTE* dictPtr = (const BYTE*)dict;
+ const BYTE* const dictEnd = dictPtr + dictSize;
+
+ RETURN_ERROR_IF(dictSize <= 8, dictionary_corrupted, "dict is too small");
+ assert(MEM_readLE32(dict) == ZSTD_MAGIC_DICTIONARY); /* dict must be valid */
+ dictPtr += 8; /* skip header = magic + dictID */
+
+ ZSTD_STATIC_ASSERT(offsetof(ZSTD_entropyDTables_t, OFTable) == offsetof(ZSTD_entropyDTables_t, LLTable) + sizeof(entropy->LLTable));
+ ZSTD_STATIC_ASSERT(offsetof(ZSTD_entropyDTables_t, MLTable) == offsetof(ZSTD_entropyDTables_t, OFTable) + sizeof(entropy->OFTable));
+ ZSTD_STATIC_ASSERT(sizeof(entropy->LLTable) + sizeof(entropy->OFTable) + sizeof(entropy->MLTable) >= HUF_DECOMPRESS_WORKSPACE_SIZE);
+ { void* const workspace = &entropy->LLTable; /* use fse tables as temporary workspace; implies fse tables are grouped together */
+ size_t const workspaceSize = sizeof(entropy->LLTable) + sizeof(entropy->OFTable) + sizeof(entropy->MLTable);
+#ifdef HUF_FORCE_DECOMPRESS_X1
+ /* in minimal huffman, we always use X1 variants */
+ size_t const hSize = HUF_readDTableX1_wksp(entropy->hufTable,
+ dictPtr, dictEnd - dictPtr,
+ workspace, workspaceSize);
+#else
+ size_t const hSize = HUF_readDTableX2_wksp(entropy->hufTable,
+ dictPtr, (size_t)(dictEnd - dictPtr),
+ workspace, workspaceSize);
+#endif
+ RETURN_ERROR_IF(HUF_isError(hSize), dictionary_corrupted, "");
+ dictPtr += hSize;
+ }
+
+ { short offcodeNCount[MaxOff+1];
+ unsigned offcodeMaxValue = MaxOff, offcodeLog;
+ size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, (size_t)(dictEnd-dictPtr));
+ RETURN_ERROR_IF(FSE_isError(offcodeHeaderSize), dictionary_corrupted, "");
+ RETURN_ERROR_IF(offcodeMaxValue > MaxOff, dictionary_corrupted, "");
+ RETURN_ERROR_IF(offcodeLog > OffFSELog, dictionary_corrupted, "");
+ ZSTD_buildFSETable( entropy->OFTable,
+ offcodeNCount, offcodeMaxValue,
+ OF_base, OF_bits,
+ offcodeLog,
+ entropy->workspace, sizeof(entropy->workspace),
+ /* bmi2 */0);
+ dictPtr += offcodeHeaderSize;
+ }
+
+ { short matchlengthNCount[MaxML+1];
+ unsigned matchlengthMaxValue = MaxML, matchlengthLog;
+ size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, (size_t)(dictEnd-dictPtr));
+ RETURN_ERROR_IF(FSE_isError(matchlengthHeaderSize), dictionary_corrupted, "");
+ RETURN_ERROR_IF(matchlengthMaxValue > MaxML, dictionary_corrupted, "");
+ RETURN_ERROR_IF(matchlengthLog > MLFSELog, dictionary_corrupted, "");
+ ZSTD_buildFSETable( entropy->MLTable,
+ matchlengthNCount, matchlengthMaxValue,
+ ML_base, ML_bits,
+ matchlengthLog,
+ entropy->workspace, sizeof(entropy->workspace),
+ /* bmi2 */ 0);
+ dictPtr += matchlengthHeaderSize;
+ }
+
+ { short litlengthNCount[MaxLL+1];
+ unsigned litlengthMaxValue = MaxLL, litlengthLog;
+ size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, (size_t)(dictEnd-dictPtr));
+ RETURN_ERROR_IF(FSE_isError(litlengthHeaderSize), dictionary_corrupted, "");
+ RETURN_ERROR_IF(litlengthMaxValue > MaxLL, dictionary_corrupted, "");
+ RETURN_ERROR_IF(litlengthLog > LLFSELog, dictionary_corrupted, "");
+ ZSTD_buildFSETable( entropy->LLTable,
+ litlengthNCount, litlengthMaxValue,
+ LL_base, LL_bits,
+ litlengthLog,
+ entropy->workspace, sizeof(entropy->workspace),
+ /* bmi2 */ 0);
+ dictPtr += litlengthHeaderSize;
+ }
+
+ RETURN_ERROR_IF(dictPtr+12 > dictEnd, dictionary_corrupted, "");
+ { int i;
+ size_t const dictContentSize = (size_t)(dictEnd - (dictPtr+12));
+ for (i=0; i<3; i++) {
+ U32 const rep = MEM_readLE32(dictPtr); dictPtr += 4;
+ RETURN_ERROR_IF(rep==0 || rep > dictContentSize,
+ dictionary_corrupted, "");
+ entropy->rep[i] = rep;
+ } }
+
+ return (size_t)(dictPtr - (const BYTE*)dict);
+}
+
+static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
+{
+ if (dictSize < 8) return ZSTD_refDictContent(dctx, dict, dictSize);
+ { U32 const magic = MEM_readLE32(dict);
+ if (magic != ZSTD_MAGIC_DICTIONARY) {
+ return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */
+ } }
+ dctx->dictID = MEM_readLE32((const char*)dict + ZSTD_FRAMEIDSIZE);
+
+ /* load entropy tables */
+ { size_t const eSize = ZSTD_loadDEntropy(&dctx->entropy, dict, dictSize);
+ RETURN_ERROR_IF(ZSTD_isError(eSize), dictionary_corrupted, "");
+ dict = (const char*)dict + eSize;
+ dictSize -= eSize;
+ }
+ dctx->litEntropy = dctx->fseEntropy = 1;
+
+ /* reference dictionary content */
+ return ZSTD_refDictContent(dctx, dict, dictSize);
+}
+
+size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx)
+{
+ assert(dctx != NULL);
+ dctx->expected = ZSTD_startingInputLength(dctx->format); /* dctx->format must be properly set */
+ dctx->stage = ZSTDds_getFrameHeaderSize;
+ dctx->processedCSize = 0;
+ dctx->decodedSize = 0;
+ dctx->previousDstEnd = NULL;
+ dctx->prefixStart = NULL;
+ dctx->virtualStart = NULL;
+ dctx->dictEnd = NULL;
+ dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */
+ dctx->litEntropy = dctx->fseEntropy = 0;
+ dctx->dictID = 0;
+ dctx->bType = bt_reserved;
+ ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue));
+ ZSTD_memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */
+ dctx->LLTptr = dctx->entropy.LLTable;
+ dctx->MLTptr = dctx->entropy.MLTable;
+ dctx->OFTptr = dctx->entropy.OFTable;
+ dctx->HUFptr = dctx->entropy.hufTable;
+ return 0;
+}
+
+size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
+{
+ FORWARD_IF_ERROR( ZSTD_decompressBegin(dctx) , "");
+ if (dict && dictSize)
+ RETURN_ERROR_IF(
+ ZSTD_isError(ZSTD_decompress_insertDictionary(dctx, dict, dictSize)),
+ dictionary_corrupted, "");
+ return 0;
+}
+
+
+/* ====== ZSTD_DDict ====== */
+
+size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict)
+{
+ DEBUGLOG(4, "ZSTD_decompressBegin_usingDDict");
+ assert(dctx != NULL);
+ if (ddict) {
+ const char* const dictStart = (const char*)ZSTD_DDict_dictContent(ddict);
+ size_t const dictSize = ZSTD_DDict_dictSize(ddict);
+ const void* const dictEnd = dictStart + dictSize;
+ dctx->ddictIsCold = (dctx->dictEnd != dictEnd);
+ DEBUGLOG(4, "DDict is %s",
+ dctx->ddictIsCold ? "~cold~" : "hot!");
+ }
+ FORWARD_IF_ERROR( ZSTD_decompressBegin(dctx) , "");
+ if (ddict) { /* NULL ddict is equivalent to no dictionary */
+ ZSTD_copyDDictParameters(dctx, ddict);
+ }
+ return 0;
+}
+
+/*! ZSTD_getDictID_fromDict() :
+ * Provides the dictID stored within dictionary.
+ * if @return == 0, the dictionary is not conformant with Zstandard specification.
+ * It can still be loaded, but as a content-only dictionary. */
+unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize)
+{
+ if (dictSize < 8) return 0;
+ if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) return 0;
+ return MEM_readLE32((const char*)dict + ZSTD_FRAMEIDSIZE);
+}
+
+/*! ZSTD_getDictID_fromFrame() :
+ * Provides the dictID required to decompress frame stored within `src`.
+ * If @return == 0, the dictID could not be decoded.
+ * This could for one of the following reasons :
+ * - The frame does not require a dictionary (most common case).
+ * - The frame was built with dictID intentionally removed.
+ * Needed dictionary is a hidden information.
+ * Note : this use case also happens when using a non-conformant dictionary.
+ * - `srcSize` is too small, and as a result, frame header could not be decoded.
+ * Note : possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`.
+ * - This is not a Zstandard frame.
+ * When identifying the exact failure cause, it's possible to use
+ * ZSTD_getFrameHeader(), which will provide a more precise error code. */
+unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize)
+{
+ ZSTD_frameHeader zfp = { 0, 0, 0, ZSTD_frame, 0, 0, 0 };
+ size_t const hError = ZSTD_getFrameHeader(&zfp, src, srcSize);
+ if (ZSTD_isError(hError)) return 0;
+ return zfp.dictID;
+}
+
+
+/*! ZSTD_decompress_usingDDict() :
+* Decompression using a pre-digested Dictionary
+* Use dictionary without significant overhead. */
+size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize,
+ const ZSTD_DDict* ddict)
+{
+ /* pass content and size in case legacy frames are encountered */
+ return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize,
+ NULL, 0,
+ ddict);
+}
+
+
+/*=====================================
+* Streaming decompression
+*====================================*/
+
+ZSTD_DStream* ZSTD_createDStream(void)
+{
+ DEBUGLOG(3, "ZSTD_createDStream");
+ return ZSTD_createDCtx_internal(ZSTD_defaultCMem);
+}
+
+ZSTD_DStream* ZSTD_initStaticDStream(void *workspace, size_t workspaceSize)
+{
+ return ZSTD_initStaticDCtx(workspace, workspaceSize);
+}
+
+ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
+{
+ return ZSTD_createDCtx_internal(customMem);
+}
+
+size_t ZSTD_freeDStream(ZSTD_DStream* zds)
+{
+ return ZSTD_freeDCtx(zds);
+}
+
+
+/* *** Initialization *** */
+
+size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_MAX + ZSTD_blockHeaderSize; }
+size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_MAX; }
+
+size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx,
+ const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType)
+{
+ RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, "");
+ ZSTD_clearDict(dctx);
+ if (dict && dictSize != 0) {
+ dctx->ddictLocal = ZSTD_createDDict_advanced(dict, dictSize, dictLoadMethod, dictContentType, dctx->customMem);
+ RETURN_ERROR_IF(dctx->ddictLocal == NULL, memory_allocation, "NULL pointer!");
+ dctx->ddict = dctx->ddictLocal;
+ dctx->dictUses = ZSTD_use_indefinitely;
+ }
+ return 0;
+}
+
+size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
+{
+ return ZSTD_DCtx_loadDictionary_advanced(dctx, dict, dictSize, ZSTD_dlm_byRef, ZSTD_dct_auto);
+}
+
+size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
+{
+ return ZSTD_DCtx_loadDictionary_advanced(dctx, dict, dictSize, ZSTD_dlm_byCopy, ZSTD_dct_auto);
+}
+
+size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType)
+{
+ FORWARD_IF_ERROR(ZSTD_DCtx_loadDictionary_advanced(dctx, prefix, prefixSize, ZSTD_dlm_byRef, dictContentType), "");
+ dctx->dictUses = ZSTD_use_once;
+ return 0;
+}
+
+size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize)
+{
+ return ZSTD_DCtx_refPrefix_advanced(dctx, prefix, prefixSize, ZSTD_dct_rawContent);
+}
+
+
+/* ZSTD_initDStream_usingDict() :
+ * return : expected size, aka ZSTD_startingInputLength().
+ * this function cannot fail */
+size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize)
+{
+ DEBUGLOG(4, "ZSTD_initDStream_usingDict");
+ FORWARD_IF_ERROR( ZSTD_DCtx_reset(zds, ZSTD_reset_session_only) , "");
+ FORWARD_IF_ERROR( ZSTD_DCtx_loadDictionary(zds, dict, dictSize) , "");
+ return ZSTD_startingInputLength(zds->format);
+}
+
+/* note : this variant can't fail */
+size_t ZSTD_initDStream(ZSTD_DStream* zds)
+{
+ DEBUGLOG(4, "ZSTD_initDStream");
+ return ZSTD_initDStream_usingDDict(zds, NULL);
+}
+
+/* ZSTD_initDStream_usingDDict() :
+ * ddict will just be referenced, and must outlive decompression session
+ * this function cannot fail */
+size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* dctx, const ZSTD_DDict* ddict)
+{
+ FORWARD_IF_ERROR( ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only) , "");
+ FORWARD_IF_ERROR( ZSTD_DCtx_refDDict(dctx, ddict) , "");
+ return ZSTD_startingInputLength(dctx->format);
+}
+
+/* ZSTD_resetDStream() :
+ * return : expected size, aka ZSTD_startingInputLength().
+ * this function cannot fail */
+size_t ZSTD_resetDStream(ZSTD_DStream* dctx)
+{
+ FORWARD_IF_ERROR(ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only), "");
+ return ZSTD_startingInputLength(dctx->format);
+}
+
+
+size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict)
+{
+ RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, "");
+ ZSTD_clearDict(dctx);
+ if (ddict) {
+ dctx->ddict = ddict;
+ dctx->dictUses = ZSTD_use_indefinitely;
+ if (dctx->refMultipleDDicts == ZSTD_rmd_refMultipleDDicts) {
+ if (dctx->ddictSet == NULL) {
+ dctx->ddictSet = ZSTD_createDDictHashSet(dctx->customMem);
+ if (!dctx->ddictSet) {
+ RETURN_ERROR(memory_allocation, "Failed to allocate memory for hash set!");
+ }
+ }
+ assert(!dctx->staticSize); /* Impossible: ddictSet cannot have been allocated if static dctx */
+ FORWARD_IF_ERROR(ZSTD_DDictHashSet_addDDict(dctx->ddictSet, ddict, dctx->customMem), "");
+ }
+ }
+ return 0;
+}
+
+/* ZSTD_DCtx_setMaxWindowSize() :
+ * note : no direct equivalence in ZSTD_DCtx_setParameter,
+ * since this version sets windowSize, and the other sets windowLog */
+size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize)
+{
+ ZSTD_bounds const bounds = ZSTD_dParam_getBounds(ZSTD_d_windowLogMax);
+ size_t const min = (size_t)1 << bounds.lowerBound;
+ size_t const max = (size_t)1 << bounds.upperBound;
+ RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, "");
+ RETURN_ERROR_IF(maxWindowSize < min, parameter_outOfBound, "");
+ RETURN_ERROR_IF(maxWindowSize > max, parameter_outOfBound, "");
+ dctx->maxWindowSize = maxWindowSize;
+ return 0;
+}
+
+size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format)
+{
+ return ZSTD_DCtx_setParameter(dctx, ZSTD_d_format, (int)format);
+}
+
+ZSTD_bounds ZSTD_dParam_getBounds(ZSTD_dParameter dParam)
+{
+ ZSTD_bounds bounds = { 0, 0, 0 };
+ switch(dParam) {
+ case ZSTD_d_windowLogMax:
+ bounds.lowerBound = ZSTD_WINDOWLOG_ABSOLUTEMIN;
+ bounds.upperBound = ZSTD_WINDOWLOG_MAX;
+ return bounds;
+ case ZSTD_d_format:
+ bounds.lowerBound = (int)ZSTD_f_zstd1;
+ bounds.upperBound = (int)ZSTD_f_zstd1_magicless;
+ ZSTD_STATIC_ASSERT(ZSTD_f_zstd1 < ZSTD_f_zstd1_magicless);
+ return bounds;
+ case ZSTD_d_stableOutBuffer:
+ bounds.lowerBound = (int)ZSTD_bm_buffered;
+ bounds.upperBound = (int)ZSTD_bm_stable;
+ return bounds;
+ case ZSTD_d_forceIgnoreChecksum:
+ bounds.lowerBound = (int)ZSTD_d_validateChecksum;
+ bounds.upperBound = (int)ZSTD_d_ignoreChecksum;
+ return bounds;
+ case ZSTD_d_refMultipleDDicts:
+ bounds.lowerBound = (int)ZSTD_rmd_refSingleDDict;
+ bounds.upperBound = (int)ZSTD_rmd_refMultipleDDicts;
+ return bounds;
+ default:;
+ }
+ bounds.error = ERROR(parameter_unsupported);
+ return bounds;
+}
+
+/* ZSTD_dParam_withinBounds:
+ * @return 1 if value is within dParam bounds,
+ * 0 otherwise */
+static int ZSTD_dParam_withinBounds(ZSTD_dParameter dParam, int value)
+{
+ ZSTD_bounds const bounds = ZSTD_dParam_getBounds(dParam);
+ if (ZSTD_isError(bounds.error)) return 0;
+ if (value < bounds.lowerBound) return 0;
+ if (value > bounds.upperBound) return 0;
+ return 1;
+}
+
+#define CHECK_DBOUNDS(p,v) { \
+ RETURN_ERROR_IF(!ZSTD_dParam_withinBounds(p, v), parameter_outOfBound, ""); \
+}
+
+size_t ZSTD_DCtx_getParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int* value)
+{
+ switch (param) {
+ case ZSTD_d_windowLogMax:
+ *value = (int)ZSTD_highbit32((U32)dctx->maxWindowSize);
+ return 0;
+ case ZSTD_d_format:
+ *value = (int)dctx->format;
+ return 0;
+ case ZSTD_d_stableOutBuffer:
+ *value = (int)dctx->outBufferMode;
+ return 0;
+ case ZSTD_d_forceIgnoreChecksum:
+ *value = (int)dctx->forceIgnoreChecksum;
+ return 0;
+ case ZSTD_d_refMultipleDDicts:
+ *value = (int)dctx->refMultipleDDicts;
+ return 0;
+ default:;
+ }
+ RETURN_ERROR(parameter_unsupported, "");
+}
+
+size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter dParam, int value)
+{
+ RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, "");
+ switch(dParam) {
+ case ZSTD_d_windowLogMax:
+ if (value == 0) value = ZSTD_WINDOWLOG_LIMIT_DEFAULT;
+ CHECK_DBOUNDS(ZSTD_d_windowLogMax, value);
+ dctx->maxWindowSize = ((size_t)1) << value;
+ return 0;
+ case ZSTD_d_format:
+ CHECK_DBOUNDS(ZSTD_d_format, value);
+ dctx->format = (ZSTD_format_e)value;
+ return 0;
+ case ZSTD_d_stableOutBuffer:
+ CHECK_DBOUNDS(ZSTD_d_stableOutBuffer, value);
+ dctx->outBufferMode = (ZSTD_bufferMode_e)value;
+ return 0;
+ case ZSTD_d_forceIgnoreChecksum:
+ CHECK_DBOUNDS(ZSTD_d_forceIgnoreChecksum, value);
+ dctx->forceIgnoreChecksum = (ZSTD_forceIgnoreChecksum_e)value;
+ return 0;
+ case ZSTD_d_refMultipleDDicts:
+ CHECK_DBOUNDS(ZSTD_d_refMultipleDDicts, value);
+ if (dctx->staticSize != 0) {
+ RETURN_ERROR(parameter_unsupported, "Static dctx does not support multiple DDicts!");
+ }
+ dctx->refMultipleDDicts = (ZSTD_refMultipleDDicts_e)value;
+ return 0;
+ default:;
+ }
+ RETURN_ERROR(parameter_unsupported, "");
+}
+
+size_t ZSTD_DCtx_reset(ZSTD_DCtx* dctx, ZSTD_ResetDirective reset)
+{
+ if ( (reset == ZSTD_reset_session_only)
+ || (reset == ZSTD_reset_session_and_parameters) ) {
+ dctx->streamStage = zdss_init;
+ dctx->noForwardProgress = 0;
+ }
+ if ( (reset == ZSTD_reset_parameters)
+ || (reset == ZSTD_reset_session_and_parameters) ) {
+ RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, "");
+ ZSTD_clearDict(dctx);
+ ZSTD_DCtx_resetParameters(dctx);
+ }
+ return 0;
+}
+
+
+size_t ZSTD_sizeof_DStream(const ZSTD_DStream* dctx)
+{
+ return ZSTD_sizeof_DCtx(dctx);
+}
+
+size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize)
+{
+ size_t const blockSize = (size_t) MIN(windowSize, ZSTD_BLOCKSIZE_MAX);
+ /* space is needed to store the litbuffer after the output of a given block without stomping the extDict of a previous run, as well as to cover both windows against wildcopy*/
+ unsigned long long const neededRBSize = windowSize + blockSize + ZSTD_BLOCKSIZE_MAX + (WILDCOPY_OVERLENGTH * 2);
+ unsigned long long const neededSize = MIN(frameContentSize, neededRBSize);
+ size_t const minRBSize = (size_t) neededSize;
+ RETURN_ERROR_IF((unsigned long long)minRBSize != neededSize,
+ frameParameter_windowTooLarge, "");
+ return minRBSize;
+}
+
+size_t ZSTD_estimateDStreamSize(size_t windowSize)
+{
+ size_t const blockSize = MIN(windowSize, ZSTD_BLOCKSIZE_MAX);
+ size_t const inBuffSize = blockSize; /* no block can be larger */
+ size_t const outBuffSize = ZSTD_decodingBufferSize_min(windowSize, ZSTD_CONTENTSIZE_UNKNOWN);
+ return ZSTD_estimateDCtxSize() + inBuffSize + outBuffSize;
+}
+
+size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize)
+{
+ U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; /* note : should be user-selectable, but requires an additional parameter (or a dctx) */
+ ZSTD_frameHeader zfh;
+ size_t const err = ZSTD_getFrameHeader(&zfh, src, srcSize);
+ if (ZSTD_isError(err)) return err;
+ RETURN_ERROR_IF(err>0, srcSize_wrong, "");
+ RETURN_ERROR_IF(zfh.windowSize > windowSizeMax,
+ frameParameter_windowTooLarge, "");
+ return ZSTD_estimateDStreamSize((size_t)zfh.windowSize);
+}
+
+
+/* ***** Decompression ***** */
+
+static int ZSTD_DCtx_isOverflow(ZSTD_DStream* zds, size_t const neededInBuffSize, size_t const neededOutBuffSize)
+{
+ return (zds->inBuffSize + zds->outBuffSize) >= (neededInBuffSize + neededOutBuffSize) * ZSTD_WORKSPACETOOLARGE_FACTOR;
+}
+
+static void ZSTD_DCtx_updateOversizedDuration(ZSTD_DStream* zds, size_t const neededInBuffSize, size_t const neededOutBuffSize)
+{
+ if (ZSTD_DCtx_isOverflow(zds, neededInBuffSize, neededOutBuffSize))
+ zds->oversizedDuration++;
+ else
+ zds->oversizedDuration = 0;
+}
+
+static int ZSTD_DCtx_isOversizedTooLong(ZSTD_DStream* zds)
+{
+ return zds->oversizedDuration >= ZSTD_WORKSPACETOOLARGE_MAXDURATION;
+}
+
+/* Checks that the output buffer hasn't changed if ZSTD_obm_stable is used. */
+static size_t ZSTD_checkOutBuffer(ZSTD_DStream const* zds, ZSTD_outBuffer const* output)
+{
+ ZSTD_outBuffer const expect = zds->expectedOutBuffer;
+ /* No requirement when ZSTD_obm_stable is not enabled. */
+ if (zds->outBufferMode != ZSTD_bm_stable)
+ return 0;
+ /* Any buffer is allowed in zdss_init, this must be the same for every other call until
+ * the context is reset.
+ */
+ if (zds->streamStage == zdss_init)
+ return 0;
+ /* The buffer must match our expectation exactly. */
+ if (expect.dst == output->dst && expect.pos == output->pos && expect.size == output->size)
+ return 0;
+ RETURN_ERROR(dstBuffer_wrong, "ZSTD_d_stableOutBuffer enabled but output differs!");
+}
+
+/* Calls ZSTD_decompressContinue() with the right parameters for ZSTD_decompressStream()
+ * and updates the stage and the output buffer state. This call is extracted so it can be
+ * used both when reading directly from the ZSTD_inBuffer, and in buffered input mode.
+ * NOTE: You must break after calling this function since the streamStage is modified.
+ */
+static size_t ZSTD_decompressContinueStream(
+ ZSTD_DStream* zds, char** op, char* oend,
+ void const* src, size_t srcSize) {
+ int const isSkipFrame = ZSTD_isSkipFrame(zds);
+ if (zds->outBufferMode == ZSTD_bm_buffered) {
+ size_t const dstSize = isSkipFrame ? 0 : zds->outBuffSize - zds->outStart;
+ size_t const decodedSize = ZSTD_decompressContinue(zds,
+ zds->outBuff + zds->outStart, dstSize, src, srcSize);
+ FORWARD_IF_ERROR(decodedSize, "");
+ if (!decodedSize && !isSkipFrame) {
+ zds->streamStage = zdss_read;
+ } else {
+ zds->outEnd = zds->outStart + decodedSize;
+ zds->streamStage = zdss_flush;
+ }
+ } else {
+ /* Write directly into the output buffer */
+ size_t const dstSize = isSkipFrame ? 0 : (size_t)(oend - *op);
+ size_t const decodedSize = ZSTD_decompressContinue(zds, *op, dstSize, src, srcSize);
+ FORWARD_IF_ERROR(decodedSize, "");
+ *op += decodedSize;
+ /* Flushing is not needed. */
+ zds->streamStage = zdss_read;
+ assert(*op <= oend);
+ assert(zds->outBufferMode == ZSTD_bm_stable);
+ }
+ return 0;
+}
+
+size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
+{
+ const char* const src = (const char*)input->src;
+ const char* const istart = input->pos != 0 ? src + input->pos : src;
+ const char* const iend = input->size != 0 ? src + input->size : src;
+ const char* ip = istart;
+ char* const dst = (char*)output->dst;
+ char* const ostart = output->pos != 0 ? dst + output->pos : dst;
+ char* const oend = output->size != 0 ? dst + output->size : dst;
+ char* op = ostart;
+ U32 someMoreWork = 1;
+
+ DEBUGLOG(5, "ZSTD_decompressStream");
+ RETURN_ERROR_IF(
+ input->pos > input->size,
+ srcSize_wrong,
+ "forbidden. in: pos: %u vs size: %u",
+ (U32)input->pos, (U32)input->size);
+ RETURN_ERROR_IF(
+ output->pos > output->size,
+ dstSize_tooSmall,
+ "forbidden. out: pos: %u vs size: %u",
+ (U32)output->pos, (U32)output->size);
+ DEBUGLOG(5, "input size : %u", (U32)(input->size - input->pos));
+ FORWARD_IF_ERROR(ZSTD_checkOutBuffer(zds, output), "");
+
+ while (someMoreWork) {
+ switch(zds->streamStage)
+ {
+ case zdss_init :
+ DEBUGLOG(5, "stage zdss_init => transparent reset ");
+ zds->streamStage = zdss_loadHeader;
+ zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
+ zds->hostageByte = 0;
+ zds->expectedOutBuffer = *output;
+ ZSTD_FALLTHROUGH;
+
+ case zdss_loadHeader :
+ DEBUGLOG(5, "stage zdss_loadHeader (srcSize : %u)", (U32)(iend - ip));
+ { size_t const hSize = ZSTD_getFrameHeader_advanced(&zds->fParams, zds->headerBuffer, zds->lhSize, zds->format);
+ if (zds->refMultipleDDicts && zds->ddictSet) {
+ ZSTD_DCtx_selectFrameDDict(zds);
+ }
+ DEBUGLOG(5, "header size : %u", (U32)hSize);
+ if (ZSTD_isError(hSize)) {
+ return hSize; /* error */
+ }
+ if (hSize != 0) { /* need more input */
+ size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */
+ size_t const remainingInput = (size_t)(iend-ip);
+ assert(iend >= ip);
+ if (toLoad > remainingInput) { /* not enough input to load full header */
+ if (remainingInput > 0) {
+ ZSTD_memcpy(zds->headerBuffer + zds->lhSize, ip, remainingInput);
+ zds->lhSize += remainingInput;
+ }
+ input->pos = input->size;
+ return (MAX((size_t)ZSTD_FRAMEHEADERSIZE_MIN(zds->format), hSize) - zds->lhSize) + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */
+ }
+ assert(ip != NULL);
+ ZSTD_memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); zds->lhSize = hSize; ip += toLoad;
+ break;
+ } }
+
+ /* check for single-pass mode opportunity */
+ if (zds->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN
+ && zds->fParams.frameType != ZSTD_skippableFrame
+ && (U64)(size_t)(oend-op) >= zds->fParams.frameContentSize) {
+ size_t const cSize = ZSTD_findFrameCompressedSize(istart, (size_t)(iend-istart));
+ if (cSize <= (size_t)(iend-istart)) {
+ /* shortcut : using single-pass mode */
+ size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, (size_t)(oend-op), istart, cSize, ZSTD_getDDict(zds));
+ if (ZSTD_isError(decompressedSize)) return decompressedSize;
+ DEBUGLOG(4, "shortcut to single-pass ZSTD_decompress_usingDDict()")
+ ip = istart + cSize;
+ op += decompressedSize;
+ zds->expected = 0;
+ zds->streamStage = zdss_init;
+ someMoreWork = 0;
+ break;
+ } }
+
+ /* Check output buffer is large enough for ZSTD_odm_stable. */
+ if (zds->outBufferMode == ZSTD_bm_stable
+ && zds->fParams.frameType != ZSTD_skippableFrame
+ && zds->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN
+ && (U64)(size_t)(oend-op) < zds->fParams.frameContentSize) {
+ RETURN_ERROR(dstSize_tooSmall, "ZSTD_obm_stable passed but ZSTD_outBuffer is too small");
+ }
+
+ /* Consume header (see ZSTDds_decodeFrameHeader) */
+ DEBUGLOG(4, "Consume header");
+ FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(zds, ZSTD_getDDict(zds)), "");
+
+ if ((MEM_readLE32(zds->headerBuffer) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */
+ zds->expected = MEM_readLE32(zds->headerBuffer + ZSTD_FRAMEIDSIZE);
+ zds->stage = ZSTDds_skipFrame;
+ } else {
+ FORWARD_IF_ERROR(ZSTD_decodeFrameHeader(zds, zds->headerBuffer, zds->lhSize), "");
+ zds->expected = ZSTD_blockHeaderSize;
+ zds->stage = ZSTDds_decodeBlockHeader;
+ }
+
+ /* control buffer memory usage */
+ DEBUGLOG(4, "Control max memory usage (%u KB <= max %u KB)",
+ (U32)(zds->fParams.windowSize >>10),
+ (U32)(zds->maxWindowSize >> 10) );
+ zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
+ RETURN_ERROR_IF(zds->fParams.windowSize > zds->maxWindowSize,
+ frameParameter_windowTooLarge, "");
+
+ /* Adapt buffer sizes to frame header instructions */
+ { size_t const neededInBuffSize = MAX(zds->fParams.blockSizeMax, 4 /* frame checksum */);
+ size_t const neededOutBuffSize = zds->outBufferMode == ZSTD_bm_buffered
+ ? ZSTD_decodingBufferSize_min(zds->fParams.windowSize, zds->fParams.frameContentSize)
+ : 0;
+
+ ZSTD_DCtx_updateOversizedDuration(zds, neededInBuffSize, neededOutBuffSize);
+
+ { int const tooSmall = (zds->inBuffSize < neededInBuffSize) || (zds->outBuffSize < neededOutBuffSize);
+ int const tooLarge = ZSTD_DCtx_isOversizedTooLong(zds);
+
+ if (tooSmall || tooLarge) {
+ size_t const bufferSize = neededInBuffSize + neededOutBuffSize;
+ DEBUGLOG(4, "inBuff : from %u to %u",
+ (U32)zds->inBuffSize, (U32)neededInBuffSize);
+ DEBUGLOG(4, "outBuff : from %u to %u",
+ (U32)zds->outBuffSize, (U32)neededOutBuffSize);
+ if (zds->staticSize) { /* static DCtx */
+ DEBUGLOG(4, "staticSize : %u", (U32)zds->staticSize);
+ assert(zds->staticSize >= sizeof(ZSTD_DCtx)); /* controlled at init */
+ RETURN_ERROR_IF(
+ bufferSize > zds->staticSize - sizeof(ZSTD_DCtx),
+ memory_allocation, "");
+ } else {
+ ZSTD_customFree(zds->inBuff, zds->customMem);
+ zds->inBuffSize = 0;
+ zds->outBuffSize = 0;
+ zds->inBuff = (char*)ZSTD_customMalloc(bufferSize, zds->customMem);
+ RETURN_ERROR_IF(zds->inBuff == NULL, memory_allocation, "");
+ }
+ zds->inBuffSize = neededInBuffSize;
+ zds->outBuff = zds->inBuff + zds->inBuffSize;
+ zds->outBuffSize = neededOutBuffSize;
+ } } }
+ zds->streamStage = zdss_read;
+ ZSTD_FALLTHROUGH;
+
+ case zdss_read:
+ DEBUGLOG(5, "stage zdss_read");
+ { size_t const neededInSize = ZSTD_nextSrcSizeToDecompressWithInputSize(zds, (size_t)(iend - ip));
+ DEBUGLOG(5, "neededInSize = %u", (U32)neededInSize);
+ if (neededInSize==0) { /* end of frame */
+ zds->streamStage = zdss_init;
+ someMoreWork = 0;
+ break;
+ }
+ if ((size_t)(iend-ip) >= neededInSize) { /* decode directly from src */
+ FORWARD_IF_ERROR(ZSTD_decompressContinueStream(zds, &op, oend, ip, neededInSize), "");
+ ip += neededInSize;
+ /* Function modifies the stage so we must break */
+ break;
+ } }
+ if (ip==iend) { someMoreWork = 0; break; } /* no more input */
+ zds->streamStage = zdss_load;
+ ZSTD_FALLTHROUGH;
+
+ case zdss_load:
+ { size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds);
+ size_t const toLoad = neededInSize - zds->inPos;
+ int const isSkipFrame = ZSTD_isSkipFrame(zds);
+ size_t loadedSize;
+ /* At this point we shouldn't be decompressing a block that we can stream. */
+ assert(neededInSize == ZSTD_nextSrcSizeToDecompressWithInputSize(zds, iend - ip));
+ if (isSkipFrame) {
+ loadedSize = MIN(toLoad, (size_t)(iend-ip));
+ } else {
+ RETURN_ERROR_IF(toLoad > zds->inBuffSize - zds->inPos,
+ corruption_detected,
+ "should never happen");
+ loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, (size_t)(iend-ip));
+ }
+ ip += loadedSize;
+ zds->inPos += loadedSize;
+ if (loadedSize < toLoad) { someMoreWork = 0; break; } /* not enough input, wait for more */
+
+ /* decode loaded input */
+ zds->inPos = 0; /* input is consumed */
+ FORWARD_IF_ERROR(ZSTD_decompressContinueStream(zds, &op, oend, zds->inBuff, neededInSize), "");
+ /* Function modifies the stage so we must break */
+ break;
+ }
+ case zdss_flush:
+ { size_t const toFlushSize = zds->outEnd - zds->outStart;
+ size_t const flushedSize = ZSTD_limitCopy(op, (size_t)(oend-op), zds->outBuff + zds->outStart, toFlushSize);
+ op += flushedSize;
+ zds->outStart += flushedSize;
+ if (flushedSize == toFlushSize) { /* flush completed */
+ zds->streamStage = zdss_read;
+ if ( (zds->outBuffSize < zds->fParams.frameContentSize)
+ && (zds->outStart + zds->fParams.blockSizeMax > zds->outBuffSize) ) {
+ DEBUGLOG(5, "restart filling outBuff from beginning (left:%i, needed:%u)",
+ (int)(zds->outBuffSize - zds->outStart),
+ (U32)zds->fParams.blockSizeMax);
+ zds->outStart = zds->outEnd = 0;
+ }
+ break;
+ } }
+ /* cannot complete flush */
+ someMoreWork = 0;
+ break;
+
+ default:
+ assert(0); /* impossible */
+ RETURN_ERROR(GENERIC, "impossible to reach"); /* some compiler require default to do something */
+ } }
+
+ /* result */
+ input->pos = (size_t)(ip - (const char*)(input->src));
+ output->pos = (size_t)(op - (char*)(output->dst));
+
+ /* Update the expected output buffer for ZSTD_obm_stable. */
+ zds->expectedOutBuffer = *output;
+
+ if ((ip==istart) && (op==ostart)) { /* no forward progress */
+ zds->noForwardProgress ++;
+ if (zds->noForwardProgress >= ZSTD_NO_FORWARD_PROGRESS_MAX) {
+ RETURN_ERROR_IF(op==oend, dstSize_tooSmall, "");
+ RETURN_ERROR_IF(ip==iend, srcSize_wrong, "");
+ assert(0);
+ }
+ } else {
+ zds->noForwardProgress = 0;
+ }
+ { size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds);
+ if (!nextSrcSizeHint) { /* frame fully decoded */
+ if (zds->outEnd == zds->outStart) { /* output fully flushed */
+ if (zds->hostageByte) {
+ if (input->pos >= input->size) {
+ /* can't release hostage (not present) */
+ zds->streamStage = zdss_read;
+ return 1;
+ }
+ input->pos++; /* release hostage */
+ } /* zds->hostageByte */
+ return 0;
+ } /* zds->outEnd == zds->outStart */
+ if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */
+ input->pos--; /* note : pos > 0, otherwise, impossible to finish reading last block */
+ zds->hostageByte=1;
+ }
+ return 1;
+ } /* nextSrcSizeHint==0 */
+ nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds) == ZSTDnit_block); /* preload header of next block */
+ assert(zds->inPos <= nextSrcSizeHint);
+ nextSrcSizeHint -= zds->inPos; /* part already loaded*/
+ return nextSrcSizeHint;
+ }
+}
+
+size_t ZSTD_decompressStream_simpleArgs (
+ ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity, size_t* dstPos,
+ const void* src, size_t srcSize, size_t* srcPos)
+{
+ ZSTD_outBuffer output = { dst, dstCapacity, *dstPos };
+ ZSTD_inBuffer input = { src, srcSize, *srcPos };
+ /* ZSTD_compress_generic() will check validity of dstPos and srcPos */
+ size_t const cErr = ZSTD_decompressStream(dctx, &output, &input);
+ *dstPos = output.pos;
+ *srcPos = input.pos;
+ return cErr;
+}