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authorNick Terrell <terrelln@fb.com>2020-09-11 16:37:08 -0700
committerNick Terrell <terrelln@fb.com>2021-11-08 16:55:32 -0800
commite0c1b49f5b674cca7b10549c53b3791d0bbc90a8 (patch)
tree1ef2c43e1fd74f910aa38bdfa8a98c9a8a708457 /lib/zstd/decompress
parent2479b523898633768e28796238534af31fbd6846 (diff)
lib: zstd: Upgrade to latest upstream zstd version 1.4.10
Upgrade to the latest upstream zstd version 1.4.10. This patch is 100% generated from upstream zstd commit 20821a46f412 [0]. This patch is very large because it is transitioning from the custom kernel zstd to using upstream directly. The new zstd follows upstreams file structure which is different. Future update patches will be much smaller because they will only contain the changes from one upstream zstd release. As an aid for review I've created a commit [1] that shows the diff between upstream zstd as-is (which doesn't compile), and the zstd code imported in this patch. The verion of zstd in this patch is generated from upstream with changes applied by automation to replace upstreams libc dependencies, remove unnecessary portability macros, replace `/**` comments with `/*` comments, and use the kernel's xxhash instead of bundling it. The benefits of this patch are as follows: 1. Using upstream directly with automated script to generate kernel code. This allows us to update the kernel every upstream release, so the kernel gets the latest bug fixes and performance improvements, and doesn't get 3 years out of date again. The automation and the translated code are tested every upstream commit to ensure it continues to work. 2. Upgrades from a custom zstd based on 1.3.1 to 1.4.10, getting 3 years of performance improvements and bug fixes. On x86_64 I've measured 15% faster BtrFS and SquashFS decompression+read speeds, 35% faster kernel decompression, and 30% faster ZRAM decompression+read speeds. 3. Zstd-1.4.10 supports negative compression levels, which allow zstd to match or subsume lzo's performance. 4. Maintains the same kernel-specific wrapper API, so no callers have to be modified with zstd version updates. One concern that was brought up was stack usage. Upstream zstd had already removed most of its heavy stack usage functions, but I just removed the last functions that allocate arrays on the stack. I've measured the high water mark for both compression and decompression before and after this patch. Decompression is approximately neutral, using about 1.2KB of stack space. Compression levels up to 3 regressed from 1.4KB -> 1.6KB, and higher compression levels regressed from 1.5KB -> 2KB. We've added unit tests upstream to prevent further regression. I believe that this is a reasonable increase, and if it does end up causing problems, this commit can be cleanly reverted, because it only touches zstd. I chose the bulk update instead of replaying upstream commits because there have been ~3500 upstream commits since the 1.3.1 release, zstd wasn't ready to be used in the kernel as-is before a month ago, and not all upstream zstd commits build. The bulk update preserves bisectablity because bugs can be bisected to the zstd version update. At that point the update can be reverted, and we can work with upstream to find and fix the bug. Note that upstream zstd release 1.4.10 doesn't exist yet. I have cut a staging branch at 20821a46f412 [0] and will apply any changes requested to the staging branch. Once we're ready to merge this update I will cut a zstd release at the commit we merge, so we have a known zstd release in the kernel. The implementation of the kernel API is contained in zstd_compress_module.c and zstd_decompress_module.c. [0] https://github.com/facebook/zstd/commit/20821a46f4122f9abd7c7b245d28162dde8129c9 [1] https://github.com/terrelln/linux/commit/e0fa481d0e3df26918da0a13749740a1f6777574 Signed-off-by: Nick Terrell <terrelln@fb.com> Tested By: Paul Jones <paul@pauljones.id.au> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 on x86-64 Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>
Diffstat (limited to 'lib/zstd/decompress')
-rw-r--r--lib/zstd/decompress/huf_decompress.c1206
-rw-r--r--lib/zstd/decompress/zstd_ddict.c241
-rw-r--r--lib/zstd/decompress/zstd_ddict.h44
-rw-r--r--lib/zstd/decompress/zstd_decompress.c2085
-rw-r--r--lib/zstd/decompress/zstd_decompress_block.c1540
-rw-r--r--lib/zstd/decompress/zstd_decompress_block.h62
-rw-r--r--lib/zstd/decompress/zstd_decompress_internal.h202
7 files changed, 5380 insertions, 0 deletions
diff --git a/lib/zstd/decompress/huf_decompress.c b/lib/zstd/decompress/huf_decompress.c
new file mode 100644
index 000000000000..05570ed5f8be
--- /dev/null
+++ b/lib/zstd/decompress/huf_decompress.c
@@ -0,0 +1,1206 @@
+/* ******************************************************************
+ * huff0 huffman decoder,
+ * part of Finite State Entropy library
+ * Copyright (c) Yann Collet, Facebook, Inc.
+ *
+ * You can contact the author at :
+ * - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ *
+ * 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.
+****************************************************************** */
+
+/* **************************************************************
+* Dependencies
+****************************************************************/
+#include "../common/zstd_deps.h" /* ZSTD_memcpy, ZSTD_memset */
+#include "../common/compiler.h"
+#include "../common/bitstream.h" /* BIT_* */
+#include "../common/fse.h" /* to compress headers */
+#define HUF_STATIC_LINKING_ONLY
+#include "../common/huf.h"
+#include "../common/error_private.h"
+
+/* **************************************************************
+* Macros
+****************************************************************/
+
+/* These two optional macros force the use one way or another of the two
+ * Huffman decompression implementations. You can't force in both directions
+ * at the same time.
+ */
+#if defined(HUF_FORCE_DECOMPRESS_X1) && \
+ defined(HUF_FORCE_DECOMPRESS_X2)
+#error "Cannot force the use of the X1 and X2 decoders at the same time!"
+#endif
+
+
+/* **************************************************************
+* Error Management
+****************************************************************/
+#define HUF_isError ERR_isError
+
+
+/* **************************************************************
+* Byte alignment for workSpace management
+****************************************************************/
+#define HUF_ALIGN(x, a) HUF_ALIGN_MASK((x), (a) - 1)
+#define HUF_ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
+
+
+/* **************************************************************
+* BMI2 Variant Wrappers
+****************************************************************/
+#if DYNAMIC_BMI2
+
+#define HUF_DGEN(fn) \
+ \
+ static size_t fn##_default( \
+ void* dst, size_t dstSize, \
+ const void* cSrc, size_t cSrcSize, \
+ const HUF_DTable* DTable) \
+ { \
+ return fn##_body(dst, dstSize, cSrc, cSrcSize, DTable); \
+ } \
+ \
+ static TARGET_ATTRIBUTE("bmi2") size_t fn##_bmi2( \
+ void* dst, size_t dstSize, \
+ const void* cSrc, size_t cSrcSize, \
+ const HUF_DTable* DTable) \
+ { \
+ return fn##_body(dst, dstSize, cSrc, cSrcSize, DTable); \
+ } \
+ \
+ static size_t fn(void* dst, size_t dstSize, void const* cSrc, \
+ size_t cSrcSize, HUF_DTable const* DTable, int bmi2) \
+ { \
+ if (bmi2) { \
+ return fn##_bmi2(dst, dstSize, cSrc, cSrcSize, DTable); \
+ } \
+ return fn##_default(dst, dstSize, cSrc, cSrcSize, DTable); \
+ }
+
+#else
+
+#define HUF_DGEN(fn) \
+ static size_t fn(void* dst, size_t dstSize, void const* cSrc, \
+ size_t cSrcSize, HUF_DTable const* DTable, int bmi2) \
+ { \
+ (void)bmi2; \
+ return fn##_body(dst, dstSize, cSrc, cSrcSize, DTable); \
+ }
+
+#endif
+
+
+/*-***************************/
+/* generic DTableDesc */
+/*-***************************/
+typedef struct { BYTE maxTableLog; BYTE tableType; BYTE tableLog; BYTE reserved; } DTableDesc;
+
+static DTableDesc HUF_getDTableDesc(const HUF_DTable* table)
+{
+ DTableDesc dtd;
+ ZSTD_memcpy(&dtd, table, sizeof(dtd));
+ return dtd;
+}
+
+
+#ifndef HUF_FORCE_DECOMPRESS_X2
+
+/*-***************************/
+/* single-symbol decoding */
+/*-***************************/
+typedef struct { BYTE byte; BYTE nbBits; } HUF_DEltX1; /* single-symbol decoding */
+
+/*
+ * Packs 4 HUF_DEltX1 structs into a U64. This is used to lay down 4 entries at
+ * a time.
+ */
+static U64 HUF_DEltX1_set4(BYTE symbol, BYTE nbBits) {
+ U64 D4;
+ if (MEM_isLittleEndian()) {
+ D4 = symbol + (nbBits << 8);
+ } else {
+ D4 = (symbol << 8) + nbBits;
+ }
+ D4 *= 0x0001000100010001ULL;
+ return D4;
+}
+
+typedef struct {
+ U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1];
+ U32 rankStart[HUF_TABLELOG_ABSOLUTEMAX + 1];
+ U32 statsWksp[HUF_READ_STATS_WORKSPACE_SIZE_U32];
+ BYTE symbols[HUF_SYMBOLVALUE_MAX + 1];
+ BYTE huffWeight[HUF_SYMBOLVALUE_MAX + 1];
+} HUF_ReadDTableX1_Workspace;
+
+
+size_t HUF_readDTableX1_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize)
+{
+ return HUF_readDTableX1_wksp_bmi2(DTable, src, srcSize, workSpace, wkspSize, /* bmi2 */ 0);
+}
+
+size_t HUF_readDTableX1_wksp_bmi2(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int bmi2)
+{
+ U32 tableLog = 0;
+ U32 nbSymbols = 0;
+ size_t iSize;
+ void* const dtPtr = DTable + 1;
+ HUF_DEltX1* const dt = (HUF_DEltX1*)dtPtr;
+ HUF_ReadDTableX1_Workspace* wksp = (HUF_ReadDTableX1_Workspace*)workSpace;
+
+ DEBUG_STATIC_ASSERT(HUF_DECOMPRESS_WORKSPACE_SIZE >= sizeof(*wksp));
+ if (sizeof(*wksp) > wkspSize) return ERROR(tableLog_tooLarge);
+
+ DEBUG_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable));
+ /* ZSTD_memset(huffWeight, 0, sizeof(huffWeight)); */ /* is not necessary, even though some analyzer complain ... */
+
+ iSize = HUF_readStats_wksp(wksp->huffWeight, HUF_SYMBOLVALUE_MAX + 1, wksp->rankVal, &nbSymbols, &tableLog, src, srcSize, wksp->statsWksp, sizeof(wksp->statsWksp), bmi2);
+ if (HUF_isError(iSize)) return iSize;
+
+ /* Table header */
+ { DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (tableLog > (U32)(dtd.maxTableLog+1)) return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */
+ dtd.tableType = 0;
+ dtd.tableLog = (BYTE)tableLog;
+ ZSTD_memcpy(DTable, &dtd, sizeof(dtd));
+ }
+
+ /* Compute symbols and rankStart given rankVal:
+ *
+ * rankVal already contains the number of values of each weight.
+ *
+ * symbols contains the symbols ordered by weight. First are the rankVal[0]
+ * weight 0 symbols, followed by the rankVal[1] weight 1 symbols, and so on.
+ * symbols[0] is filled (but unused) to avoid a branch.
+ *
+ * rankStart contains the offset where each rank belongs in the DTable.
+ * rankStart[0] is not filled because there are no entries in the table for
+ * weight 0.
+ */
+ {
+ int n;
+ int nextRankStart = 0;
+ int const unroll = 4;
+ int const nLimit = (int)nbSymbols - unroll + 1;
+ for (n=0; n<(int)tableLog+1; n++) {
+ U32 const curr = nextRankStart;
+ nextRankStart += wksp->rankVal[n];
+ wksp->rankStart[n] = curr;
+ }
+ for (n=0; n < nLimit; n += unroll) {
+ int u;
+ for (u=0; u < unroll; ++u) {
+ size_t const w = wksp->huffWeight[n+u];
+ wksp->symbols[wksp->rankStart[w]++] = (BYTE)(n+u);
+ }
+ }
+ for (; n < (int)nbSymbols; ++n) {
+ size_t const w = wksp->huffWeight[n];
+ wksp->symbols[wksp->rankStart[w]++] = (BYTE)n;
+ }
+ }
+
+ /* fill DTable
+ * We fill all entries of each weight in order.
+ * That way length is a constant for each iteration of the outter loop.
+ * We can switch based on the length to a different inner loop which is
+ * optimized for that particular case.
+ */
+ {
+ U32 w;
+ int symbol=wksp->rankVal[0];
+ int rankStart=0;
+ for (w=1; w<tableLog+1; ++w) {
+ int const symbolCount = wksp->rankVal[w];
+ int const length = (1 << w) >> 1;
+ int uStart = rankStart;
+ BYTE const nbBits = (BYTE)(tableLog + 1 - w);
+ int s;
+ int u;
+ switch (length) {
+ case 1:
+ for (s=0; s<symbolCount; ++s) {
+ HUF_DEltX1 D;
+ D.byte = wksp->symbols[symbol + s];
+ D.nbBits = nbBits;
+ dt[uStart] = D;
+ uStart += 1;
+ }
+ break;
+ case 2:
+ for (s=0; s<symbolCount; ++s) {
+ HUF_DEltX1 D;
+ D.byte = wksp->symbols[symbol + s];
+ D.nbBits = nbBits;
+ dt[uStart+0] = D;
+ dt[uStart+1] = D;
+ uStart += 2;
+ }
+ break;
+ case 4:
+ for (s=0; s<symbolCount; ++s) {
+ U64 const D4 = HUF_DEltX1_set4(wksp->symbols[symbol + s], nbBits);
+ MEM_write64(dt + uStart, D4);
+ uStart += 4;
+ }
+ break;
+ case 8:
+ for (s=0; s<symbolCount; ++s) {
+ U64 const D4 = HUF_DEltX1_set4(wksp->symbols[symbol + s], nbBits);
+ MEM_write64(dt + uStart, D4);
+ MEM_write64(dt + uStart + 4, D4);
+ uStart += 8;
+ }
+ break;
+ default:
+ for (s=0; s<symbolCount; ++s) {
+ U64 const D4 = HUF_DEltX1_set4(wksp->symbols[symbol + s], nbBits);
+ for (u=0; u < length; u += 16) {
+ MEM_write64(dt + uStart + u + 0, D4);
+ MEM_write64(dt + uStart + u + 4, D4);
+ MEM_write64(dt + uStart + u + 8, D4);
+ MEM_write64(dt + uStart + u + 12, D4);
+ }
+ assert(u == length);
+ uStart += length;
+ }
+ break;
+ }
+ symbol += symbolCount;
+ rankStart += symbolCount * length;
+ }
+ }
+ return iSize;
+}
+
+FORCE_INLINE_TEMPLATE BYTE
+HUF_decodeSymbolX1(BIT_DStream_t* Dstream, const HUF_DEltX1* dt, const U32 dtLog)
+{
+ size_t const val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */
+ BYTE const c = dt[val].byte;
+ BIT_skipBits(Dstream, dt[val].nbBits);
+ return c;
+}
+
+#define HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr) \
+ *ptr++ = HUF_decodeSymbolX1(DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX1_1(ptr, DStreamPtr) \
+ if (MEM_64bits() || (HUF_TABLELOG_MAX<=12)) \
+ HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr)
+
+#define HUF_DECODE_SYMBOLX1_2(ptr, DStreamPtr) \
+ if (MEM_64bits()) \
+ HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr)
+
+HINT_INLINE size_t
+HUF_decodeStreamX1(BYTE* p, BIT_DStream_t* const bitDPtr, BYTE* const pEnd, const HUF_DEltX1* const dt, const U32 dtLog)
+{
+ BYTE* const pStart = p;
+
+ /* up to 4 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-3)) {
+ HUF_DECODE_SYMBOLX1_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX1_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX1_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX1_0(p, bitDPtr);
+ }
+
+ /* [0-3] symbols remaining */
+ if (MEM_32bits())
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd))
+ HUF_DECODE_SYMBOLX1_0(p, bitDPtr);
+
+ /* no more data to retrieve from bitstream, no need to reload */
+ while (p < pEnd)
+ HUF_DECODE_SYMBOLX1_0(p, bitDPtr);
+
+ return pEnd-pStart;
+}
+
+FORCE_INLINE_TEMPLATE size_t
+HUF_decompress1X1_usingDTable_internal_body(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ BYTE* op = (BYTE*)dst;
+ BYTE* const oend = op + dstSize;
+ const void* dtPtr = DTable + 1;
+ const HUF_DEltX1* const dt = (const HUF_DEltX1*)dtPtr;
+ BIT_DStream_t bitD;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ U32 const dtLog = dtd.tableLog;
+
+ CHECK_F( BIT_initDStream(&bitD, cSrc, cSrcSize) );
+
+ HUF_decodeStreamX1(op, &bitD, oend, dt, dtLog);
+
+ if (!BIT_endOfDStream(&bitD)) return ERROR(corruption_detected);
+
+ return dstSize;
+}
+
+FORCE_INLINE_TEMPLATE size_t
+HUF_decompress4X1_usingDTable_internal_body(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ /* Check */
+ if (cSrcSize < 10) return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
+
+ { const BYTE* const istart = (const BYTE*) cSrc;
+ BYTE* const ostart = (BYTE*) dst;
+ BYTE* const oend = ostart + dstSize;
+ BYTE* const olimit = oend - 3;
+ const void* const dtPtr = DTable + 1;
+ const HUF_DEltX1* const dt = (const HUF_DEltX1*)dtPtr;
+
+ /* Init */
+ BIT_DStream_t bitD1;
+ BIT_DStream_t bitD2;
+ BIT_DStream_t bitD3;
+ BIT_DStream_t bitD4;
+ size_t const length1 = MEM_readLE16(istart);
+ size_t const length2 = MEM_readLE16(istart+2);
+ size_t const length3 = MEM_readLE16(istart+4);
+ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
+ const BYTE* const istart1 = istart + 6; /* jumpTable */
+ const BYTE* const istart2 = istart1 + length1;
+ const BYTE* const istart3 = istart2 + length2;
+ const BYTE* const istart4 = istart3 + length3;
+ const size_t segmentSize = (dstSize+3) / 4;
+ BYTE* const opStart2 = ostart + segmentSize;
+ BYTE* const opStart3 = opStart2 + segmentSize;
+ BYTE* const opStart4 = opStart3 + segmentSize;
+ BYTE* op1 = ostart;
+ BYTE* op2 = opStart2;
+ BYTE* op3 = opStart3;
+ BYTE* op4 = opStart4;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ U32 const dtLog = dtd.tableLog;
+ U32 endSignal = 1;
+
+ if (length4 > cSrcSize) return ERROR(corruption_detected); /* overflow */
+ CHECK_F( BIT_initDStream(&bitD1, istart1, length1) );
+ CHECK_F( BIT_initDStream(&bitD2, istart2, length2) );
+ CHECK_F( BIT_initDStream(&bitD3, istart3, length3) );
+ CHECK_F( BIT_initDStream(&bitD4, istart4, length4) );
+
+ /* up to 16 symbols per loop (4 symbols per stream) in 64-bit mode */
+ for ( ; (endSignal) & (op4 < olimit) ; ) {
+ HUF_DECODE_SYMBOLX1_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX1_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX1_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX1_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_0(op4, &bitD4);
+ endSignal &= BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished;
+ }
+
+ /* check corruption */
+ /* note : should not be necessary : op# advance in lock step, and we control op4.
+ * but curiously, binary generated by gcc 7.2 & 7.3 with -mbmi2 runs faster when >=1 test is present */
+ if (op1 > opStart2) return ERROR(corruption_detected);
+ if (op2 > opStart3) return ERROR(corruption_detected);
+ if (op3 > opStart4) return ERROR(corruption_detected);
+ /* note : op4 supposed already verified within main loop */
+
+ /* finish bitStreams one by one */
+ HUF_decodeStreamX1(op1, &bitD1, opStart2, dt, dtLog);
+ HUF_decodeStreamX1(op2, &bitD2, opStart3, dt, dtLog);
+ HUF_decodeStreamX1(op3, &bitD3, opStart4, dt, dtLog);
+ HUF_decodeStreamX1(op4, &bitD4, oend, dt, dtLog);
+
+ /* check */
+ { U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
+ if (!endCheck) return ERROR(corruption_detected); }
+
+ /* decoded size */
+ return dstSize;
+ }
+}
+
+
+typedef size_t (*HUF_decompress_usingDTable_t)(void *dst, size_t dstSize,
+ const void *cSrc,
+ size_t cSrcSize,
+ const HUF_DTable *DTable);
+
+HUF_DGEN(HUF_decompress1X1_usingDTable_internal)
+HUF_DGEN(HUF_decompress4X1_usingDTable_internal)
+
+
+
+size_t HUF_decompress1X1_usingDTable(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 0) return ERROR(GENERIC);
+ return HUF_decompress1X1_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+}
+
+size_t HUF_decompress1X1_DCtx_wksp(HUF_DTable* DCtx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize)
+{
+ const BYTE* ip = (const BYTE*) cSrc;
+
+ size_t const hSize = HUF_readDTableX1_wksp(DCtx, cSrc, cSrcSize, workSpace, wkspSize);
+ if (HUF_isError(hSize)) return hSize;
+ if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
+ ip += hSize; cSrcSize -= hSize;
+
+ return HUF_decompress1X1_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx, /* bmi2 */ 0);
+}
+
+
+size_t HUF_decompress4X1_usingDTable(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 0) return ERROR(GENERIC);
+ return HUF_decompress4X1_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+}
+
+static size_t HUF_decompress4X1_DCtx_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize, int bmi2)
+{
+ const BYTE* ip = (const BYTE*) cSrc;
+
+ size_t const hSize = HUF_readDTableX1_wksp_bmi2(dctx, cSrc, cSrcSize, workSpace, wkspSize, bmi2);
+ if (HUF_isError(hSize)) return hSize;
+ if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
+ ip += hSize; cSrcSize -= hSize;
+
+ return HUF_decompress4X1_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx, bmi2);
+}
+
+size_t HUF_decompress4X1_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize)
+{
+ return HUF_decompress4X1_DCtx_wksp_bmi2(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize, 0);
+}
+
+
+#endif /* HUF_FORCE_DECOMPRESS_X2 */
+
+
+#ifndef HUF_FORCE_DECOMPRESS_X1
+
+/* *************************/
+/* double-symbols decoding */
+/* *************************/
+
+typedef struct { U16 sequence; BYTE nbBits; BYTE length; } HUF_DEltX2; /* double-symbols decoding */
+typedef struct { BYTE symbol; BYTE weight; } sortedSymbol_t;
+typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1];
+typedef rankValCol_t rankVal_t[HUF_TABLELOG_MAX];
+
+
+/* HUF_fillDTableX2Level2() :
+ * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */
+static void HUF_fillDTableX2Level2(HUF_DEltX2* DTable, U32 sizeLog, const U32 consumed,
+ const U32* rankValOrigin, const int minWeight,
+ const sortedSymbol_t* sortedSymbols, const U32 sortedListSize,
+ U32 nbBitsBaseline, U16 baseSeq, U32* wksp, size_t wkspSize)
+{
+ HUF_DEltX2 DElt;
+ U32* rankVal = wksp;
+
+ assert(wkspSize >= HUF_TABLELOG_MAX + 1);
+ (void)wkspSize;
+ /* get pre-calculated rankVal */
+ ZSTD_memcpy(rankVal, rankValOrigin, sizeof(U32) * (HUF_TABLELOG_MAX + 1));
+
+ /* fill skipped values */
+ if (minWeight>1) {
+ U32 i, skipSize = rankVal[minWeight];
+ MEM_writeLE16(&(DElt.sequence), baseSeq);
+ DElt.nbBits = (BYTE)(consumed);
+ DElt.length = 1;
+ for (i = 0; i < skipSize; i++)
+ DTable[i] = DElt;
+ }
+
+ /* fill DTable */
+ { U32 s; for (s=0; s<sortedListSize; s++) { /* note : sortedSymbols already skipped */
+ const U32 symbol = sortedSymbols[s].symbol;
+ const U32 weight = sortedSymbols[s].weight;
+ const U32 nbBits = nbBitsBaseline - weight;
+ const U32 length = 1 << (sizeLog-nbBits);
+ const U32 start = rankVal[weight];
+ U32 i = start;
+ const U32 end = start + length;
+
+ MEM_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8)));
+ DElt.nbBits = (BYTE)(nbBits + consumed);
+ DElt.length = 2;
+ do { DTable[i++] = DElt; } while (i<end); /* since length >= 1 */
+
+ rankVal[weight] += length;
+ } }
+}
+
+
+static void HUF_fillDTableX2(HUF_DEltX2* DTable, const U32 targetLog,
+ const sortedSymbol_t* sortedList, const U32 sortedListSize,
+ const U32* rankStart, rankVal_t rankValOrigin, const U32 maxWeight,
+ const U32 nbBitsBaseline, U32* wksp, size_t wkspSize)
+{
+ U32* rankVal = wksp;
+ const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */
+ const U32 minBits = nbBitsBaseline - maxWeight;
+ U32 s;
+
+ assert(wkspSize >= HUF_TABLELOG_MAX + 1);
+ wksp += HUF_TABLELOG_MAX + 1;
+ wkspSize -= HUF_TABLELOG_MAX + 1;
+
+ ZSTD_memcpy(rankVal, rankValOrigin, sizeof(U32) * (HUF_TABLELOG_MAX + 1));
+
+ /* fill DTable */
+ for (s=0; s<sortedListSize; s++) {
+ const U16 symbol = sortedList[s].symbol;
+ const U32 weight = sortedList[s].weight;
+ const U32 nbBits = nbBitsBaseline - weight;
+ const U32 start = rankVal[weight];
+ const U32 length = 1 << (targetLog-nbBits);
+
+ if (targetLog-nbBits >= minBits) { /* enough room for a second symbol */
+ U32 sortedRank;
+ int minWeight = nbBits + scaleLog;
+ if (minWeight < 1) minWeight = 1;
+ sortedRank = rankStart[minWeight];
+ HUF_fillDTableX2Level2(DTable+start, targetLog-nbBits, nbBits,
+ rankValOrigin[nbBits], minWeight,
+ sortedList+sortedRank, sortedListSize-sortedRank,
+ nbBitsBaseline, symbol, wksp, wkspSize);
+ } else {
+ HUF_DEltX2 DElt;
+ MEM_writeLE16(&(DElt.sequence), symbol);
+ DElt.nbBits = (BYTE)(nbBits);
+ DElt.length = 1;
+ { U32 const end = start + length;
+ U32 u;
+ for (u = start; u < end; u++) DTable[u] = DElt;
+ } }
+ rankVal[weight] += length;
+ }
+}
+
+typedef struct {
+ rankValCol_t rankVal[HUF_TABLELOG_MAX];
+ U32 rankStats[HUF_TABLELOG_MAX + 1];
+ U32 rankStart0[HUF_TABLELOG_MAX + 2];
+ sortedSymbol_t sortedSymbol[HUF_SYMBOLVALUE_MAX + 1];
+ BYTE weightList[HUF_SYMBOLVALUE_MAX + 1];
+ U32 calleeWksp[HUF_READ_STATS_WORKSPACE_SIZE_U32];
+} HUF_ReadDTableX2_Workspace;
+
+size_t HUF_readDTableX2_wksp(HUF_DTable* DTable,
+ const void* src, size_t srcSize,
+ void* workSpace, size_t wkspSize)
+{
+ U32 tableLog, maxW, sizeOfSort, nbSymbols;
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ U32 const maxTableLog = dtd.maxTableLog;
+ size_t iSize;
+ void* dtPtr = DTable+1; /* force compiler to avoid strict-aliasing */
+ HUF_DEltX2* const dt = (HUF_DEltX2*)dtPtr;
+ U32 *rankStart;
+
+ HUF_ReadDTableX2_Workspace* const wksp = (HUF_ReadDTableX2_Workspace*)workSpace;
+
+ if (sizeof(*wksp) > wkspSize) return ERROR(GENERIC);
+
+ rankStart = wksp->rankStart0 + 1;
+ ZSTD_memset(wksp->rankStats, 0, sizeof(wksp->rankStats));
+ ZSTD_memset(wksp->rankStart0, 0, sizeof(wksp->rankStart0));
+
+ DEBUG_STATIC_ASSERT(sizeof(HUF_DEltX2) == sizeof(HUF_DTable)); /* if compiler fails here, assertion is wrong */
+ if (maxTableLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge);
+ /* ZSTD_memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */
+
+ iSize = HUF_readStats_wksp(wksp->weightList, HUF_SYMBOLVALUE_MAX + 1, wksp->rankStats, &nbSymbols, &tableLog, src, srcSize, wksp->calleeWksp, sizeof(wksp->calleeWksp), /* bmi2 */ 0);
+ if (HUF_isError(iSize)) return iSize;
+
+ /* check result */
+ if (tableLog > maxTableLog) return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */
+
+ /* find maxWeight */
+ for (maxW = tableLog; wksp->rankStats[maxW]==0; maxW--) {} /* necessarily finds a solution before 0 */
+
+ /* Get start index of each weight */
+ { U32 w, nextRankStart = 0;
+ for (w=1; w<maxW+1; w++) {
+ U32 curr = nextRankStart;
+ nextRankStart += wksp->rankStats[w];
+ rankStart[w] = curr;
+ }
+ rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/
+ sizeOfSort = nextRankStart;
+ }
+
+ /* sort symbols by weight */
+ { U32 s;
+ for (s=0; s<nbSymbols; s++) {
+ U32 const w = wksp->weightList[s];
+ U32 const r = rankStart[w]++;
+ wksp->sortedSymbol[r].symbol = (BYTE)s;
+ wksp->sortedSymbol[r].weight = (BYTE)w;
+ }
+ rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */
+ }
+
+ /* Build rankVal */
+ { U32* const rankVal0 = wksp->rankVal[0];
+ { int const rescale = (maxTableLog-tableLog) - 1; /* tableLog <= maxTableLog */
+ U32 nextRankVal = 0;
+ U32 w;
+ for (w=1; w<maxW+1; w++) {
+ U32 curr = nextRankVal;
+ nextRankVal += wksp->rankStats[w] << (w+rescale);
+ rankVal0[w] = curr;
+ } }
+ { U32 const minBits = tableLog+1 - maxW;
+ U32 consumed;
+ for (consumed = minBits; consumed < maxTableLog - minBits + 1; consumed++) {
+ U32* const rankValPtr = wksp->rankVal[consumed];
+ U32 w;
+ for (w = 1; w < maxW+1; w++) {
+ rankValPtr[w] = rankVal0[w] >> consumed;
+ } } } }
+
+ HUF_fillDTableX2(dt, maxTableLog,
+ wksp->sortedSymbol, sizeOfSort,
+ wksp->rankStart0, wksp->rankVal, maxW,
+ tableLog+1,
+ wksp->calleeWksp, sizeof(wksp->calleeWksp) / sizeof(U32));
+
+ dtd.tableLog = (BYTE)maxTableLog;
+ dtd.tableType = 1;
+ ZSTD_memcpy(DTable, &dtd, sizeof(dtd));
+ return iSize;
+}
+
+
+FORCE_INLINE_TEMPLATE U32
+HUF_decodeSymbolX2(void* op, BIT_DStream_t* DStream, const HUF_DEltX2* dt, const U32 dtLog)
+{
+ size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
+ ZSTD_memcpy(op, dt+val, 2);
+ BIT_skipBits(DStream, dt[val].nbBits);
+ return dt[val].length;
+}
+
+FORCE_INLINE_TEMPLATE U32
+HUF_decodeLastSymbolX2(void* op, BIT_DStream_t* DStream, const HUF_DEltX2* dt, const U32 dtLog)
+{
+ size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
+ ZSTD_memcpy(op, dt+val, 1);
+ if (dt[val].length==1) BIT_skipBits(DStream, dt[val].nbBits);
+ else {
+ if (DStream->bitsConsumed < (sizeof(DStream->bitContainer)*8)) {
+ BIT_skipBits(DStream, dt[val].nbBits);
+ if (DStream->bitsConsumed > (sizeof(DStream->bitContainer)*8))
+ /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
+ DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);
+ } }
+ return 1;
+}
+
+#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) \
+ ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
+ if (MEM_64bits() || (HUF_TABLELOG_MAX<=12)) \
+ ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
+ if (MEM_64bits()) \
+ ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog)
+
+HINT_INLINE size_t
+HUF_decodeStreamX2(BYTE* p, BIT_DStream_t* bitDPtr, BYTE* const pEnd,
+ const HUF_DEltX2* const dt, const U32 dtLog)
+{
+ BYTE* const pStart = p;
+
+ /* up to 8 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-(sizeof(bitDPtr->bitContainer)-1))) {
+ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ }
+
+ /* closer to end : up to 2 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd-2))
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+
+ while (p <= pEnd-2)
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr); /* no need to reload : reached the end of DStream */
+
+ if (p < pEnd)
+ p += HUF_decodeLastSymbolX2(p, bitDPtr, dt, dtLog);
+
+ return p-pStart;
+}
+
+FORCE_INLINE_TEMPLATE size_t
+HUF_decompress1X2_usingDTable_internal_body(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ BIT_DStream_t bitD;
+
+ /* Init */
+ CHECK_F( BIT_initDStream(&bitD, cSrc, cSrcSize) );
+
+ /* decode */
+ { BYTE* const ostart = (BYTE*) dst;
+ BYTE* const oend = ostart + dstSize;
+ const void* const dtPtr = DTable+1; /* force compiler to not use strict-aliasing */
+ const HUF_DEltX2* const dt = (const HUF_DEltX2*)dtPtr;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ HUF_decodeStreamX2(ostart, &bitD, oend, dt, dtd.tableLog);
+ }
+
+ /* check */
+ if (!BIT_endOfDStream(&bitD)) return ERROR(corruption_detected);
+
+ /* decoded size */
+ return dstSize;
+}
+
+FORCE_INLINE_TEMPLATE size_t
+HUF_decompress4X2_usingDTable_internal_body(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ if (cSrcSize < 10) return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
+
+ { const BYTE* const istart = (const BYTE*) cSrc;
+ BYTE* const ostart = (BYTE*) dst;
+ BYTE* const oend = ostart + dstSize;
+ BYTE* const olimit = oend - (sizeof(size_t)-1);
+ const void* const dtPtr = DTable+1;
+ const HUF_DEltX2* const dt = (const HUF_DEltX2*)dtPtr;
+
+ /* Init */
+ BIT_DStream_t bitD1;
+ BIT_DStream_t bitD2;
+ BIT_DStream_t bitD3;
+ BIT_DStream_t bitD4;
+ size_t const length1 = MEM_readLE16(istart);
+ size_t const length2 = MEM_readLE16(istart+2);
+ size_t const length3 = MEM_readLE16(istart+4);
+ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
+ const BYTE* const istart1 = istart + 6; /* jumpTable */
+ const BYTE* const istart2 = istart1 + length1;
+ const BYTE* const istart3 = istart2 + length2;
+ const BYTE* const istart4 = istart3 + length3;
+ size_t const segmentSize = (dstSize+3) / 4;
+ BYTE* const opStart2 = ostart + segmentSize;
+ BYTE* const opStart3 = opStart2 + segmentSize;
+ BYTE* const opStart4 = opStart3 + segmentSize;
+ BYTE* op1 = ostart;
+ BYTE* op2 = opStart2;
+ BYTE* op3 = opStart3;
+ BYTE* op4 = opStart4;
+ U32 endSignal = 1;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ U32 const dtLog = dtd.tableLog;
+
+ if (length4 > cSrcSize) return ERROR(corruption_detected); /* overflow */
+ CHECK_F( BIT_initDStream(&bitD1, istart1, length1) );
+ CHECK_F( BIT_initDStream(&bitD2, istart2, length2) );
+ CHECK_F( BIT_initDStream(&bitD3, istart3, length3) );
+ CHECK_F( BIT_initDStream(&bitD4, istart4, length4) );
+
+ /* 16-32 symbols per loop (4-8 symbols per stream) */
+ for ( ; (endSignal) & (op4 < olimit); ) {
+#if defined(__clang__) && (defined(__x86_64__) || defined(__i386__))
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
+ endSignal &= BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished;
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
+ endSignal &= BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished;
+#else
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
+ endSignal = (U32)LIKELY(
+ (BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished)
+ & (BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished)
+ & (BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished)
+ & (BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished));
+#endif
+ }
+
+ /* check corruption */
+ if (op1 > opStart2) return ERROR(corruption_detected);
+ if (op2 > opStart3) return ERROR(corruption_detected);
+ if (op3 > opStart4) return ERROR(corruption_detected);
+ /* note : op4 already verified within main loop */
+
+ /* finish bitStreams one by one */
+ HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog);
+ HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog);
+ HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog);
+ HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog);
+
+ /* check */
+ { U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
+ if (!endCheck) return ERROR(corruption_detected); }
+
+ /* decoded size */
+ return dstSize;
+ }
+}
+
+HUF_DGEN(HUF_decompress1X2_usingDTable_internal)
+HUF_DGEN(HUF_decompress4X2_usingDTable_internal)
+
+size_t HUF_decompress1X2_usingDTable(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 1) return ERROR(GENERIC);
+ return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+}
+
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* DCtx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize)
+{
+ const BYTE* ip = (const BYTE*) cSrc;
+
+ size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize,
+ workSpace, wkspSize);
+ if (HUF_isError(hSize)) return hSize;
+ if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
+ ip += hSize; cSrcSize -= hSize;
+
+ return HUF_decompress1X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx, /* bmi2 */ 0);
+}
+
+
+size_t HUF_decompress4X2_usingDTable(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 1) return ERROR(GENERIC);
+ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+}
+
+static size_t HUF_decompress4X2_DCtx_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize, int bmi2)
+{
+ const BYTE* ip = (const BYTE*) cSrc;
+
+ size_t hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize,
+ workSpace, wkspSize);
+ if (HUF_isError(hSize)) return hSize;
+ if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
+ ip += hSize; cSrcSize -= hSize;
+
+ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx, bmi2);
+}
+
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize)
+{
+ return HUF_decompress4X2_DCtx_wksp_bmi2(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize, /* bmi2 */ 0);
+}
+
+
+#endif /* HUF_FORCE_DECOMPRESS_X1 */
+
+
+/* ***********************************/
+/* Universal decompression selectors */
+/* ***********************************/
+
+size_t HUF_decompress1X_usingDTable(void* dst, size_t maxDstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)dtd;
+ assert(dtd.tableType == 0);
+ return HUF_decompress1X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)dtd;
+ assert(dtd.tableType == 1);
+ return HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+#else
+ return dtd.tableType ? HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0) :
+ HUF_decompress1X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+#endif
+}
+
+size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)dtd;
+ assert(dtd.tableType == 0);
+ return HUF_decompress4X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)dtd;
+ assert(dtd.tableType == 1);
+ return HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+#else
+ return dtd.tableType ? HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0) :
+ HUF_decompress4X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, /* bmi2 */ 0);
+#endif
+}
+
+
+#if !defined(HUF_FORCE_DECOMPRESS_X1) && !defined(HUF_FORCE_DECOMPRESS_X2)
+typedef struct { U32 tableTime; U32 decode256Time; } algo_time_t;
+static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] =
+{
+ /* single, double, quad */
+ {{0,0}, {1,1}, {2,2}}, /* Q==0 : impossible */
+ {{0,0}, {1,1}, {2,2}}, /* Q==1 : impossible */
+ {{ 38,130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */
+ {{ 448,128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */
+ {{ 556,128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */
+ {{ 714,128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */
+ {{ 883,128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */
+ {{ 897,128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */
+ {{ 926,128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */
+ {{ 947,128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */
+ {{1107,128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */
+ {{1177,128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */
+ {{1242,128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */
+ {{1349,128}, {2644,106}, {5260,106}}, /* Q ==13 : 81-87% */
+ {{1455,128}, {2422,124}, {4174,124}}, /* Q ==14 : 87-93% */
+ {{ 722,128}, {1891,145}, {1936,146}}, /* Q ==15 : 93-99% */
+};
+#endif
+
+/* HUF_selectDecoder() :
+ * Tells which decoder is likely to decode faster,
+ * based on a set of pre-computed metrics.
+ * @return : 0==HUF_decompress4X1, 1==HUF_decompress4X2 .
+ * Assumption : 0 < dstSize <= 128 KB */
+U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize)
+{
+ assert(dstSize > 0);
+ assert(dstSize <= 128*1024);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)dstSize;
+ (void)cSrcSize;
+ return 0;
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)dstSize;
+ (void)cSrcSize;
+ return 1;
+#else
+ /* decoder timing evaluation */
+ { U32 const Q = (cSrcSize >= dstSize) ? 15 : (U32)(cSrcSize * 16 / dstSize); /* Q < 16 */
+ U32 const D256 = (U32)(dstSize >> 8);
+ U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256);
+ U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256);
+ DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, to reduce cache eviction */
+ return DTime1 < DTime0;
+ }
+#endif
+}
+
+
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst,
+ size_t dstSize, const void* cSrc,
+ size_t cSrcSize, void* workSpace,
+ size_t wkspSize)
+{
+ /* validation checks */
+ if (dstSize == 0) return ERROR(dstSize_tooSmall);
+ if (cSrcSize == 0) return ERROR(corruption_detected);
+
+ { U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)algoNb;
+ assert(algoNb == 0);
+ return HUF_decompress4X1_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)algoNb;
+ assert(algoNb == 1);
+ return HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize);
+#else
+ return algoNb ? HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc,
+ cSrcSize, workSpace, wkspSize):
+ HUF_decompress4X1_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize);
+#endif
+ }
+}
+
+size_t HUF_decompress1X_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ void* workSpace, size_t wkspSize)
+{
+ /* validation checks */
+ if (dstSize == 0) return ERROR(dstSize_tooSmall);
+ if (cSrcSize > dstSize) return ERROR(corruption_detected); /* invalid */
+ if (cSrcSize == dstSize) { ZSTD_memcpy(dst, cSrc, dstSize); return dstSize; } /* not compressed */
+ if (cSrcSize == 1) { ZSTD_memset(dst, *(const BYTE*)cSrc, dstSize); return dstSize; } /* RLE */
+
+ { U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)algoNb;
+ assert(algoNb == 0);
+ return HUF_decompress1X1_DCtx_wksp(dctx, dst, dstSize, cSrc,
+ cSrcSize, workSpace, wkspSize);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)algoNb;
+ assert(algoNb == 1);
+ return HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc,
+ cSrcSize, workSpace, wkspSize);
+#else
+ return algoNb ? HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc,
+ cSrcSize, workSpace, wkspSize):
+ HUF_decompress1X1_DCtx_wksp(dctx, dst, dstSize, cSrc,
+ cSrcSize, workSpace, wkspSize);
+#endif
+ }
+}
+
+
+size_t HUF_decompress1X_usingDTable_bmi2(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int bmi2)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)dtd;
+ assert(dtd.tableType == 0);
+ return HUF_decompress1X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)dtd;
+ assert(dtd.tableType == 1);
+ return HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2);
+#else
+ return dtd.tableType ? HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2) :
+ HUF_decompress1X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2);
+#endif
+}
+
+#ifndef HUF_FORCE_DECOMPRESS_X2
+size_t HUF_decompress1X1_DCtx_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int bmi2)
+{
+ const BYTE* ip = (const BYTE*) cSrc;
+
+ size_t const hSize = HUF_readDTableX1_wksp_bmi2(dctx, cSrc, cSrcSize, workSpace, wkspSize, bmi2);
+ if (HUF_isError(hSize)) return hSize;
+ if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
+ ip += hSize; cSrcSize -= hSize;
+
+ return HUF_decompress1X1_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx, bmi2);
+}
+#endif
+
+size_t HUF_decompress4X_usingDTable_bmi2(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int bmi2)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)dtd;
+ assert(dtd.tableType == 0);
+ return HUF_decompress4X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)dtd;
+ assert(dtd.tableType == 1);
+ return HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2);
+#else
+ return dtd.tableType ? HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2) :
+ HUF_decompress4X1_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable, bmi2);
+#endif
+}
+
+size_t HUF_decompress4X_hufOnly_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int bmi2)
+{
+ /* validation checks */
+ if (dstSize == 0) return ERROR(dstSize_tooSmall);
+ if (cSrcSize == 0) return ERROR(corruption_detected);
+
+ { U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
+#if defined(HUF_FORCE_DECOMPRESS_X1)
+ (void)algoNb;
+ assert(algoNb == 0);
+ return HUF_decompress4X1_DCtx_wksp_bmi2(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize, bmi2);
+#elif defined(HUF_FORCE_DECOMPRESS_X2)
+ (void)algoNb;
+ assert(algoNb == 1);
+ return HUF_decompress4X2_DCtx_wksp_bmi2(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize, bmi2);
+#else
+ return algoNb ? HUF_decompress4X2_DCtx_wksp_bmi2(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize, bmi2) :
+ HUF_decompress4X1_DCtx_wksp_bmi2(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize, bmi2);
+#endif
+ }
+}
+
diff --git a/lib/zstd/decompress/zstd_ddict.c b/lib/zstd/decompress/zstd_ddict.c
new file mode 100644
index 000000000000..dbbc7919de53
--- /dev/null
+++ b/lib/zstd/decompress/zstd_ddict.c
@@ -0,0 +1,241 @@
+/*
+ * 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.
+ */
+
+/* zstd_ddict.c :
+ * concentrates all logic that needs to know the internals of ZSTD_DDict object */
+
+/*-*******************************************************
+* Dependencies
+*********************************************************/
+#include "../common/zstd_deps.h" /* ZSTD_memcpy, ZSTD_memmove, ZSTD_memset */
+#include "../common/cpu.h" /* bmi2 */
+#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 "zstd_decompress_internal.h"
+#include "zstd_ddict.h"
+
+
+
+
+/*-*******************************************************
+* Types
+*********************************************************/
+struct ZSTD_DDict_s {
+ void* dictBuffer;
+ const void* dictContent;
+ size_t dictSize;
+ ZSTD_entropyDTables_t entropy;
+ U32 dictID;
+ U32 entropyPresent;
+ ZSTD_customMem cMem;
+}; /* typedef'd to ZSTD_DDict within "zstd.h" */
+
+const void* ZSTD_DDict_dictContent(const ZSTD_DDict* ddict)
+{
+ assert(ddict != NULL);
+ return ddict->dictContent;
+}
+
+size_t ZSTD_DDict_dictSize(const ZSTD_DDict* ddict)
+{
+ assert(ddict != NULL);
+ return ddict->dictSize;
+}
+
+void ZSTD_copyDDictParameters(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict)
+{
+ DEBUGLOG(4, "ZSTD_copyDDictParameters");
+ assert(dctx != NULL);
+ assert(ddict != NULL);
+ dctx->dictID = ddict->dictID;
+ dctx->prefixStart = ddict->dictContent;
+ dctx->virtualStart = ddict->dictContent;
+ dctx->dictEnd = (const BYTE*)ddict->dictContent + ddict->dictSize;
+ dctx->previousDstEnd = dctx->dictEnd;
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ dctx->dictContentBeginForFuzzing = dctx->prefixStart;
+ dctx->dictContentEndForFuzzing = dctx->previousDstEnd;
+#endif
+ if (ddict->entropyPresent) {
+ dctx->litEntropy = 1;
+ dctx->fseEntropy = 1;
+ dctx->LLTptr = ddict->entropy.LLTable;
+ dctx->MLTptr = ddict->entropy.MLTable;
+ dctx->OFTptr = ddict->entropy.OFTable;
+ dctx->HUFptr = ddict->entropy.hufTable;
+ dctx->entropy.rep[0] = ddict->entropy.rep[0];
+ dctx->entropy.rep[1] = ddict->entropy.rep[1];
+ dctx->entropy.rep[2] = ddict->entropy.rep[2];
+ } else {
+ dctx->litEntropy = 0;
+ dctx->fseEntropy = 0;
+ }
+}
+
+
+static size_t
+ZSTD_loadEntropy_intoDDict(ZSTD_DDict* ddict,
+ ZSTD_dictContentType_e dictContentType)
+{
+ ddict->dictID = 0;
+ ddict->entropyPresent = 0;
+ if (dictContentType == ZSTD_dct_rawContent) return 0;
+
+ if (ddict->dictSize < 8) {
+ if (dictContentType == ZSTD_dct_fullDict)
+ return ERROR(dictionary_corrupted); /* only accept specified dictionaries */
+ return 0; /* pure content mode */
+ }
+ { U32 const magic = MEM_readLE32(ddict->dictContent);
+ if (magic != ZSTD_MAGIC_DICTIONARY) {
+ if (dictContentType == ZSTD_dct_fullDict)
+ return ERROR(dictionary_corrupted); /* only accept specified dictionaries */
+ return 0; /* pure content mode */
+ }
+ }
+ ddict->dictID = MEM_readLE32((const char*)ddict->dictContent + ZSTD_FRAMEIDSIZE);
+
+ /* load entropy tables */
+ RETURN_ERROR_IF(ZSTD_isError(ZSTD_loadDEntropy(
+ &ddict->entropy, ddict->dictContent, ddict->dictSize)),
+ dictionary_corrupted, "");
+ ddict->entropyPresent = 1;
+ return 0;
+}
+
+
+static size_t ZSTD_initDDict_internal(ZSTD_DDict* ddict,
+ const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType)
+{
+ if ((dictLoadMethod == ZSTD_dlm_byRef) || (!dict) || (!dictSize)) {
+ ddict->dictBuffer = NULL;
+ ddict->dictContent = dict;
+ if (!dict) dictSize = 0;
+ } else {
+ void* const internalBuffer = ZSTD_customMalloc(dictSize, ddict->cMem);
+ ddict->dictBuffer = internalBuffer;
+ ddict->dictContent = internalBuffer;
+ if (!internalBuffer) return ERROR(memory_allocation);
+ ZSTD_memcpy(internalBuffer, dict, dictSize);
+ }
+ ddict->dictSize = dictSize;
+ ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */
+
+ /* parse dictionary content */
+ FORWARD_IF_ERROR( ZSTD_loadEntropy_intoDDict(ddict, dictContentType) , "");
+
+ return 0;
+}
+
+ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType,
+ ZSTD_customMem customMem)
+{
+ if ((!customMem.customAlloc) ^ (!customMem.customFree)) return NULL;
+
+ { ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_customMalloc(sizeof(ZSTD_DDict), customMem);
+ if (ddict == NULL) return NULL;
+ ddict->cMem = customMem;
+ { size_t const initResult = ZSTD_initDDict_internal(ddict,
+ dict, dictSize,
+ dictLoadMethod, dictContentType);
+ if (ZSTD_isError(initResult)) {
+ ZSTD_freeDDict(ddict);
+ return NULL;
+ } }
+ return ddict;
+ }
+}
+
+/*! ZSTD_createDDict() :
+* Create a digested dictionary, to start decompression without startup delay.
+* `dict` content is copied inside DDict.
+* Consequently, `dict` can be released after `ZSTD_DDict` creation */
+ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
+{
+ ZSTD_customMem const allocator = { NULL, NULL, NULL };
+ return ZSTD_createDDict_advanced(dict, dictSize, ZSTD_dlm_byCopy, ZSTD_dct_auto, allocator);
+}
+
+/*! ZSTD_createDDict_byReference() :
+ * Create a digested dictionary, to start decompression without startup delay.
+ * Dictionary content is simply referenced, it will be accessed during decompression.
+ * Warning : dictBuffer must outlive DDict (DDict must be freed before dictBuffer) */
+ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize)
+{
+ ZSTD_customMem const allocator = { NULL, NULL, NULL };
+ return ZSTD_createDDict_advanced(dictBuffer, dictSize, ZSTD_dlm_byRef, ZSTD_dct_auto, allocator);
+}
+
+
+const ZSTD_DDict* ZSTD_initStaticDDict(
+ void* sBuffer, size_t sBufferSize,
+ const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType)
+{
+ size_t const neededSpace = sizeof(ZSTD_DDict)
+ + (dictLoadMethod == ZSTD_dlm_byRef ? 0 : dictSize);
+ ZSTD_DDict* const ddict = (ZSTD_DDict*)sBuffer;
+ assert(sBuffer != NULL);
+ assert(dict != NULL);
+ if ((size_t)sBuffer & 7) return NULL; /* 8-aligned */
+ if (sBufferSize < neededSpace) return NULL;
+ if (dictLoadMethod == ZSTD_dlm_byCopy) {
+ ZSTD_memcpy(ddict+1, dict, dictSize); /* local copy */
+ dict = ddict+1;
+ }
+ if (ZSTD_isError( ZSTD_initDDict_internal(ddict,
+ dict, dictSize,
+ ZSTD_dlm_byRef, dictContentType) ))
+ return NULL;
+ return ddict;
+}
+
+
+size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
+{
+ if (ddict==NULL) return 0; /* support free on NULL */
+ { ZSTD_customMem const cMem = ddict->cMem;
+ ZSTD_customFree(ddict->dictBuffer, cMem);
+ ZSTD_customFree(ddict, cMem);
+ return 0;
+ }
+}
+
+/*! ZSTD_estimateDDictSize() :
+ * Estimate amount of memory that will be needed to create a dictionary for decompression.
+ * Note : dictionary created by reference using ZSTD_dlm_byRef are smaller */
+size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod)
+{
+ return sizeof(ZSTD_DDict) + (dictLoadMethod == ZSTD_dlm_byRef ? 0 : dictSize);
+}
+
+size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
+{
+ if (ddict==NULL) return 0; /* support sizeof on NULL */
+ return sizeof(*ddict) + (ddict->dictBuffer ? ddict->dictSize : 0) ;
+}
+
+/*! ZSTD_getDictID_fromDDict() :
+ * Provides the dictID of the dictionary loaded into `ddict`.
+ * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
+ * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */
+unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict)
+{
+ if (ddict==NULL) return 0;
+ return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize);
+}
diff --git a/lib/zstd/decompress/zstd_ddict.h b/lib/zstd/decompress/zstd_ddict.h
new file mode 100644
index 000000000000..8c1a79d666f8
--- /dev/null
+++ b/lib/zstd/decompress/zstd_ddict.h
@@ -0,0 +1,44 @@
+/*
+ * 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.
+ */
+
+
+#ifndef ZSTD_DDICT_H
+#define ZSTD_DDICT_H
+
+/*-*******************************************************
+ * Dependencies
+ *********************************************************/
+#include "../common/zstd_deps.h" /* size_t */
+#include <linux/zstd.h> /* ZSTD_DDict, and several public functions */
+
+
+/*-*******************************************************
+ * Interface
+ *********************************************************/
+
+/* note: several prototypes are already published in `zstd.h` :
+ * ZSTD_createDDict()
+ * ZSTD_createDDict_byReference()
+ * ZSTD_createDDict_advanced()
+ * ZSTD_freeDDict()
+ * ZSTD_initStaticDDict()
+ * ZSTD_sizeof_DDict()
+ * ZSTD_estimateDDictSize()
+ * ZSTD_getDictID_fromDict()
+ */
+
+const void* ZSTD_DDict_dictContent(const ZSTD_DDict* ddict);
+size_t ZSTD_DDict_dictSize(const ZSTD_DDict* ddict);
+
+void ZSTD_copyDDictParameters(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
+
+
+
+#endif /* ZSTD_DDICT_H */
diff --git a/lib/zstd/decompress/zstd_decompress.c b/lib/zstd/decompress/zstd_decompress.c
new file mode 100644
index 000000000000..b4d81d84479a
--- /dev/null
+++ b/lib/zstd/decompress/zstd_decompress.c
@@ -0,0 +1,2085 @@
+/*
+ * 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/cpu.h" /* bmi2 */
+#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->legacyContext = NULL;
+ dctx->previousLegacyVersion = 0;
+ dctx->noForwardProgress = 0;
+ dctx->oversizedDuration = 0;
+ dctx->bmi2 = ZSTD_cpuid_bmi2(ZSTD_cpuid());
+ 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;
+}
+
+ZSTD_DCtx* ZSTD_createDCtx_advanced(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(void)
+{
+ DEBUGLOG(3, "ZSTD_createDCtx");
+ return ZSTD_createDCtx_advanced(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_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_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);
+ 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();
+ 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 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 MIN(MAX(inputSize, 1), 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);
+ 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_createDStream_advanced(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_advanced(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);
+ unsigned long long const neededRBSize = windowSize + blockSize + (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->legacyVersion = 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;
+}
diff --git a/lib/zstd/decompress/zstd_decompress_block.c b/lib/zstd/decompress/zstd_decompress_block.c
new file mode 100644
index 000000000000..2d101d9a842e
--- /dev/null
+++ b/lib/zstd/decompress/zstd_decompress_block.c
@@ -0,0 +1,1540 @@
+/*
+ * 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.
+ */
+
+/* zstd_decompress_block :
+ * this module takes care of decompressing _compressed_ block */
+
+/*-*******************************************************
+* Dependencies
+*********************************************************/
+#include "../common/zstd_deps.h" /* ZSTD_memcpy, ZSTD_memmove, ZSTD_memset */
+#include "../common/compiler.h" /* prefetch */
+#include "../common/cpu.h" /* bmi2 */
+#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 "../common/zstd_internal.h"
+#include "zstd_decompress_internal.h" /* ZSTD_DCtx */
+#include "zstd_ddict.h" /* ZSTD_DDictDictContent */
+#include "zstd_decompress_block.h"
+
+/*_*******************************************************
+* Macros
+**********************************************************/
+
+/* These two optional macros force the use one way or another of the two
+ * ZSTD_decompressSequences implementations. You can't force in both directions
+ * at the same time.
+ */
+#if defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
+ defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
+#error "Cannot force the use of the short and the long ZSTD_decompressSequences variants!"
+#endif
+
+
+/*_*******************************************************
+* Memory operations
+**********************************************************/
+static void ZSTD_copy4(void* dst, const void* src) { ZSTD_memcpy(dst, src, 4); }
+
+
+/*-*************************************************************
+ * Block decoding
+ ***************************************************************/
+
+/*! ZSTD_getcBlockSize() :
+ * Provides the size of compressed block from block header `src` */
+size_t ZSTD_getcBlockSize(const void* src, size_t srcSize,
+ blockProperties_t* bpPtr)
+{
+ RETURN_ERROR_IF(srcSize < ZSTD_blockHeaderSize, srcSize_wrong, "");
+
+ { U32 const cBlockHeader = MEM_readLE24(src);
+ U32 const cSize = cBlockHeader >> 3;
+ bpPtr->lastBlock = cBlockHeader & 1;
+ bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3);
+ bpPtr->origSize = cSize; /* only useful for RLE */
+ if (bpPtr->blockType == bt_rle) return 1;
+ RETURN_ERROR_IF(bpPtr->blockType == bt_reserved, corruption_detected, "");
+ return cSize;
+ }
+}
+
+
+/* Hidden declaration for fullbench */
+size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
+ const void* src, size_t srcSize);
+/*! ZSTD_decodeLiteralsBlock() :
+ * @return : nb of bytes read from src (< srcSize )
+ * note : symbol not declared but exposed for fullbench */
+size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
+ const void* src, size_t srcSize) /* note : srcSize < BLOCKSIZE */
+{
+ DEBUGLOG(5, "ZSTD_decodeLiteralsBlock");
+ RETURN_ERROR_IF(srcSize < MIN_CBLOCK_SIZE, corruption_detected, "");
+
+ { const BYTE* const istart = (const BYTE*) src;
+ symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3);
+
+ switch(litEncType)
+ {
+ case set_repeat:
+ DEBUGLOG(5, "set_repeat flag : re-using stats from previous compressed literals block");
+ RETURN_ERROR_IF(dctx->litEntropy==0, dictionary_corrupted, "");
+ ZSTD_FALLTHROUGH;
+
+ case set_compressed:
+ RETURN_ERROR_IF(srcSize < 5, corruption_detected, "srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3");
+ { size_t lhSize, litSize, litCSize;
+ U32 singleStream=0;
+ U32 const lhlCode = (istart[0] >> 2) & 3;
+ U32 const lhc = MEM_readLE32(istart);
+ size_t hufSuccess;
+ switch(lhlCode)
+ {
+ case 0: case 1: default: /* note : default is impossible, since lhlCode into [0..3] */
+ /* 2 - 2 - 10 - 10 */
+ singleStream = !lhlCode;
+ lhSize = 3;
+ litSize = (lhc >> 4) & 0x3FF;
+ litCSize = (lhc >> 14) & 0x3FF;
+ break;
+ case 2:
+ /* 2 - 2 - 14 - 14 */
+ lhSize = 4;
+ litSize = (lhc >> 4) & 0x3FFF;
+ litCSize = lhc >> 18;
+ break;
+ case 3:
+ /* 2 - 2 - 18 - 18 */
+ lhSize = 5;
+ litSize = (lhc >> 4) & 0x3FFFF;
+ litCSize = (lhc >> 22) + ((size_t)istart[4] << 10);
+ break;
+ }
+ RETURN_ERROR_IF(litSize > ZSTD_BLOCKSIZE_MAX, corruption_detected, "");
+ RETURN_ERROR_IF(litCSize + lhSize > srcSize, corruption_detected, "");
+
+ /* prefetch huffman table if cold */
+ if (dctx->ddictIsCold && (litSize > 768 /* heuristic */)) {
+ PREFETCH_AREA(dctx->HUFptr, sizeof(dctx->entropy.hufTable));
+ }
+
+ if (litEncType==set_repeat) {
+ if (singleStream) {
+ hufSuccess = HUF_decompress1X_usingDTable_bmi2(
+ dctx->litBuffer, litSize, istart+lhSize, litCSize,
+ dctx->HUFptr, dctx->bmi2);
+ } else {
+ hufSuccess = HUF_decompress4X_usingDTable_bmi2(
+ dctx->litBuffer, litSize, istart+lhSize, litCSize,
+ dctx->HUFptr, dctx->bmi2);
+ }
+ } else {
+ if (singleStream) {
+#if defined(HUF_FORCE_DECOMPRESS_X2)
+ hufSuccess = HUF_decompress1X_DCtx_wksp(
+ dctx->entropy.hufTable, dctx->litBuffer, litSize,
+ istart+lhSize, litCSize, dctx->workspace,
+ sizeof(dctx->workspace));
+#else
+ hufSuccess = HUF_decompress1X1_DCtx_wksp_bmi2(
+ dctx->entropy.hufTable, dctx->litBuffer, litSize,
+ istart+lhSize, litCSize, dctx->workspace,
+ sizeof(dctx->workspace), dctx->bmi2);
+#endif
+ } else {
+ hufSuccess = HUF_decompress4X_hufOnly_wksp_bmi2(
+ dctx->entropy.hufTable, dctx->litBuffer, litSize,
+ istart+lhSize, litCSize, dctx->workspace,
+ sizeof(dctx->workspace), dctx->bmi2);
+ }
+ }
+
+ RETURN_ERROR_IF(HUF_isError(hufSuccess), corruption_detected, "");
+
+ dctx->litPtr = dctx->litBuffer;
+ dctx->litSize = litSize;
+ dctx->litEntropy = 1;
+ if (litEncType==set_compressed) dctx->HUFptr = dctx->entropy.hufTable;
+ ZSTD_memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
+ return litCSize + lhSize;
+ }
+
+ case set_basic:
+ { size_t litSize, lhSize;
+ U32 const lhlCode = ((istart[0]) >> 2) & 3;
+ switch(lhlCode)
+ {
+ case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */
+ lhSize = 1;
+ litSize = istart[0] >> 3;
+ break;
+ case 1:
+ lhSize = 2;
+ litSize = MEM_readLE16(istart) >> 4;
+ break;
+ case 3:
+ lhSize = 3;
+ litSize = MEM_readLE24(istart) >> 4;
+ break;
+ }
+
+ if (lhSize+litSize+WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */
+ RETURN_ERROR_IF(litSize+lhSize > srcSize, corruption_detected, "");
+ ZSTD_memcpy(dctx->litBuffer, istart+lhSize, litSize);
+ dctx->litPtr = dctx->litBuffer;
+ dctx->litSize = litSize;
+ ZSTD_memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
+ return lhSize+litSize;
+ }
+ /* direct reference into compressed stream */
+ dctx->litPtr = istart+lhSize;
+ dctx->litSize = litSize;
+ return lhSize+litSize;
+ }
+
+ case set_rle:
+ { U32 const lhlCode = ((istart[0]) >> 2) & 3;
+ size_t litSize, lhSize;
+ switch(lhlCode)
+ {
+ case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */
+ lhSize = 1;
+ litSize = istart[0] >> 3;
+ break;
+ case 1:
+ lhSize = 2;
+ litSize = MEM_readLE16(istart) >> 4;
+ break;
+ case 3:
+ lhSize = 3;
+ litSize = MEM_readLE24(istart) >> 4;
+ RETURN_ERROR_IF(srcSize<4, corruption_detected, "srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4");
+ break;
+ }
+ RETURN_ERROR_IF(litSize > ZSTD_BLOCKSIZE_MAX, corruption_detected, "");
+ ZSTD_memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH);
+ dctx->litPtr = dctx->litBuffer;
+ dctx->litSize = litSize;
+ return lhSize+1;
+ }
+ default:
+ RETURN_ERROR(corruption_detected, "impossible");
+ }
+ }
+}
+
+/* Default FSE distribution tables.
+ * These are pre-calculated FSE decoding tables using default distributions as defined in specification :
+ * https://github.com/facebook/zstd/blob/release/doc/zstd_compression_format.md#default-distributions
+ * They were generated programmatically with following method :
+ * - start from default distributions, present in /lib/common/zstd_internal.h
+ * - generate tables normally, using ZSTD_buildFSETable()
+ * - printout the content of tables
+ * - pretify output, report below, test with fuzzer to ensure it's correct */
+
+/* Default FSE distribution table for Literal Lengths */
+static const ZSTD_seqSymbol LL_defaultDTable[(1<<LL_DEFAULTNORMLOG)+1] = {
+ { 1, 1, 1, LL_DEFAULTNORMLOG}, /* header : fastMode, tableLog */
+ /* nextState, nbAddBits, nbBits, baseVal */
+ { 0, 0, 4, 0}, { 16, 0, 4, 0},
+ { 32, 0, 5, 1}, { 0, 0, 5, 3},
+ { 0, 0, 5, 4}, { 0, 0, 5, 6},
+ { 0, 0, 5, 7}, { 0, 0, 5, 9},
+ { 0, 0, 5, 10}, { 0, 0, 5, 12},
+ { 0, 0, 6, 14}, { 0, 1, 5, 16},
+ { 0, 1, 5, 20}, { 0, 1, 5, 22},
+ { 0, 2, 5, 28}, { 0, 3, 5, 32},
+ { 0, 4, 5, 48}, { 32, 6, 5, 64},
+ { 0, 7, 5, 128}, { 0, 8, 6, 256},
+ { 0, 10, 6, 1024}, { 0, 12, 6, 4096},
+ { 32, 0, 4, 0}, { 0, 0, 4, 1},
+ { 0, 0, 5, 2}, { 32, 0, 5, 4},
+ { 0, 0, 5, 5}, { 32, 0, 5, 7},
+ { 0, 0, 5, 8}, { 32, 0, 5, 10},
+ { 0, 0, 5, 11}, { 0, 0, 6, 13},
+ { 32, 1, 5, 16}, { 0, 1, 5, 18},
+ { 32, 1, 5, 22}, { 0, 2, 5, 24},
+ { 32, 3, 5, 32}, { 0, 3, 5, 40},
+ { 0, 6, 4, 64}, { 16, 6, 4, 64},
+ { 32, 7, 5, 128}, { 0, 9, 6, 512},
+ { 0, 11, 6, 2048}, { 48, 0, 4, 0},
+ { 16, 0, 4, 1}, { 32, 0, 5, 2},
+ { 32, 0, 5, 3}, { 32, 0, 5, 5},
+ { 32, 0, 5, 6}, { 32, 0, 5, 8},
+ { 32, 0, 5, 9}, { 32, 0, 5, 11},
+ { 32, 0, 5, 12}, { 0, 0, 6, 15},
+ { 32, 1, 5, 18}, { 32, 1, 5, 20},
+ { 32, 2, 5, 24}, { 32, 2, 5, 28},
+ { 32, 3, 5, 40}, { 32, 4, 5, 48},
+ { 0, 16, 6,65536}, { 0, 15, 6,32768},
+ { 0, 14, 6,16384}, { 0, 13, 6, 8192},
+}; /* LL_defaultDTable */
+
+/* Default FSE distribution table for Offset Codes */
+static const ZSTD_seqSymbol OF_defaultDTable[(1<<OF_DEFAULTNORMLOG)+1] = {
+ { 1, 1, 1, OF_DEFAULTNORMLOG}, /* header : fastMode, tableLog */
+ /* nextState, nbAddBits, nbBits, baseVal */
+ { 0, 0, 5, 0}, { 0, 6, 4, 61},
+ { 0, 9, 5, 509}, { 0, 15, 5,32765},
+ { 0, 21, 5,2097149}, { 0, 3, 5, 5},
+ { 0, 7, 4, 125}, { 0, 12, 5, 4093},
+ { 0, 18, 5,262141}, { 0, 23, 5,8388605},
+ { 0, 5, 5, 29}, { 0, 8, 4, 253},
+ { 0, 14, 5,16381}, { 0, 20, 5,1048573},
+ { 0, 2, 5, 1}, { 16, 7, 4, 125},
+ { 0, 11, 5, 2045}, { 0, 17, 5,131069},
+ { 0, 22, 5,4194301}, { 0, 4, 5, 13},
+ { 16, 8, 4, 253}, { 0, 13, 5, 8189},
+ { 0, 19, 5,524285}, { 0, 1, 5, 1},
+ { 16, 6, 4, 61}, { 0, 10, 5, 1021},
+ { 0, 16, 5,65533}, { 0, 28, 5,268435453},
+ { 0, 27, 5,134217725}, { 0, 26, 5,67108861},
+ { 0, 25, 5,33554429}, { 0, 24, 5,16777213},
+}; /* OF_defaultDTable */
+
+
+/* Default FSE distribution table for Match Lengths */
+static const ZSTD_seqSymbol ML_defaultDTable[(1<<ML_DEFAULTNORMLOG)+1] = {
+ { 1, 1, 1, ML_DEFAULTNORMLOG}, /* header : fastMode, tableLog */
+ /* nextState, nbAddBits, nbBits, baseVal */
+ { 0, 0, 6, 3}, { 0, 0, 4, 4},
+ { 32, 0, 5, 5}, { 0, 0, 5, 6},
+ { 0, 0, 5, 8}, { 0, 0, 5, 9},
+ { 0, 0, 5, 11}, { 0, 0, 6, 13},
+ { 0, 0, 6, 16}, { 0, 0, 6, 19},
+ { 0, 0, 6, 22}, { 0, 0, 6, 25},
+ { 0, 0, 6, 28}, { 0, 0, 6, 31},
+ { 0, 0, 6, 34}, { 0, 1, 6, 37},
+ { 0, 1, 6, 41}, { 0, 2, 6, 47},
+ { 0, 3, 6, 59}, { 0, 4, 6, 83},
+ { 0, 7, 6, 131}, { 0, 9, 6, 515},
+ { 16, 0, 4, 4}, { 0, 0, 4, 5},
+ { 32, 0, 5, 6}, { 0, 0, 5, 7},
+ { 32, 0, 5, 9}, { 0, 0, 5, 10},
+ { 0, 0, 6, 12}, { 0, 0, 6, 15},
+ { 0, 0, 6, 18}, { 0, 0, 6, 21},
+ { 0, 0, 6, 24}, { 0, 0, 6, 27},
+ { 0, 0, 6, 30}, { 0, 0, 6, 33},
+ { 0, 1, 6, 35}, { 0, 1, 6, 39},
+ { 0, 2, 6, 43}, { 0, 3, 6, 51},
+ { 0, 4, 6, 67}, { 0, 5, 6, 99},
+ { 0, 8, 6, 259}, { 32, 0, 4, 4},
+ { 48, 0, 4, 4}, { 16, 0, 4, 5},
+ { 32, 0, 5, 7}, { 32, 0, 5, 8},
+ { 32, 0, 5, 10}, { 32, 0, 5, 11},
+ { 0, 0, 6, 14}, { 0, 0, 6, 17},
+ { 0, 0, 6, 20}, { 0, 0, 6, 23},
+ { 0, 0, 6, 26}, { 0, 0, 6, 29},
+ { 0, 0, 6, 32}, { 0, 16, 6,65539},
+ { 0, 15, 6,32771}, { 0, 14, 6,16387},
+ { 0, 13, 6, 8195}, { 0, 12, 6, 4099},
+ { 0, 11, 6, 2051}, { 0, 10, 6, 1027},
+}; /* ML_defaultDTable */
+
+
+static void ZSTD_buildSeqTable_rle(ZSTD_seqSymbol* dt, U32 baseValue, U32 nbAddBits)
+{
+ void* ptr = dt;
+ ZSTD_seqSymbol_header* const DTableH = (ZSTD_seqSymbol_header*)ptr;
+ ZSTD_seqSymbol* const cell = dt + 1;
+
+ DTableH->tableLog = 0;
+ DTableH->fastMode = 0;
+
+ cell->nbBits = 0;
+ cell->nextState = 0;
+ assert(nbAddBits < 255);
+ cell->nbAdditionalBits = (BYTE)nbAddBits;
+ cell->baseValue = baseValue;
+}
+
+
+/* ZSTD_buildFSETable() :
+ * generate FSE decoding table for one symbol (ll, ml or off)
+ * cannot fail if input is valid =>
+ * all inputs are presumed validated at this stage */
+FORCE_INLINE_TEMPLATE
+void ZSTD_buildFSETable_body(ZSTD_seqSymbol* dt,
+ const short* normalizedCounter, unsigned maxSymbolValue,
+ const U32* baseValue, const U32* nbAdditionalBits,
+ unsigned tableLog, void* wksp, size_t wkspSize)
+{
+ ZSTD_seqSymbol* const tableDecode = dt+1;
+ U32 const maxSV1 = maxSymbolValue + 1;
+ U32 const tableSize = 1 << tableLog;
+
+ U16* symbolNext = (U16*)wksp;
+ BYTE* spread = (BYTE*)(symbolNext + MaxSeq + 1);
+ U32 highThreshold = tableSize - 1;
+
+
+ /* Sanity Checks */
+ assert(maxSymbolValue <= MaxSeq);
+ assert(tableLog <= MaxFSELog);
+ assert(wkspSize >= ZSTD_BUILD_FSE_TABLE_WKSP_SIZE);
+ (void)wkspSize;
+ /* Init, lay down lowprob symbols */
+ { ZSTD_seqSymbol_header DTableH;
+ DTableH.tableLog = tableLog;
+ DTableH.fastMode = 1;
+ { S16 const largeLimit= (S16)(1 << (tableLog-1));
+ U32 s;
+ for (s=0; s<maxSV1; s++) {
+ if (normalizedCounter[s]==-1) {
+ tableDecode[highThreshold--].baseValue = s;
+ symbolNext[s] = 1;
+ } else {
+ if (normalizedCounter[s] >= largeLimit) DTableH.fastMode=0;
+ assert(normalizedCounter[s]>=0);
+ symbolNext[s] = (U16)normalizedCounter[s];
+ } } }
+ ZSTD_memcpy(dt, &DTableH, sizeof(DTableH));
+ }
+
+ /* Spread symbols */
+ assert(tableSize <= 512);
+ /* Specialized symbol spreading for the case when there are
+ * no low probability (-1 count) symbols. When compressing
+ * small blocks we avoid low probability symbols to hit this
+ * case, since header decoding speed matters more.
+ */
+ if (highThreshold == tableSize - 1) {
+ size_t const tableMask = tableSize-1;
+ size_t const step = FSE_TABLESTEP(tableSize);
+ /* First lay down the symbols in order.
+ * We use a uint64_t to lay down 8 bytes at a time. This reduces branch
+ * misses since small blocks generally have small table logs, so nearly
+ * all symbols have counts <= 8. We ensure we have 8 bytes at the end of
+ * our buffer to handle the over-write.
+ */
+ {
+ U64 const add = 0x0101010101010101ull;
+ size_t pos = 0;
+ U64 sv = 0;
+ U32 s;
+ for (s=0; s<maxSV1; ++s, sv += add) {
+ int i;
+ int const n = normalizedCounter[s];
+ MEM_write64(spread + pos, sv);
+ for (i = 8; i < n; i += 8) {
+ MEM_write64(spread + pos + i, sv);
+ }
+ pos += n;
+ }
+ }
+ /* Now we spread those positions across the table.
+ * The benefit of doing it in two stages is that we avoid the the
+ * variable size inner loop, which caused lots of branch misses.
+ * Now we can run through all the positions without any branch misses.
+ * We unroll the loop twice, since that is what emperically worked best.
+ */
+ {
+ size_t position = 0;
+ size_t s;
+ size_t const unroll = 2;
+ assert(tableSize % unroll == 0); /* FSE_MIN_TABLELOG is 5 */
+ for (s = 0; s < (size_t)tableSize; s += unroll) {
+ size_t u;
+ for (u = 0; u < unroll; ++u) {
+ size_t const uPosition = (position + (u * step)) & tableMask;
+ tableDecode[uPosition].baseValue = spread[s + u];
+ }
+ position = (position + (unroll * step)) & tableMask;
+ }
+ assert(position == 0);
+ }
+ } else {
+ U32 const tableMask = tableSize-1;
+ U32 const step = FSE_TABLESTEP(tableSize);
+ U32 s, position = 0;
+ for (s=0; s<maxSV1; s++) {
+ int i;
+ int const n = normalizedCounter[s];
+ for (i=0; i<n; i++) {
+ tableDecode[position].baseValue = s;
+ position = (position + step) & tableMask;
+ while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */
+ } }
+ assert(position == 0); /* position must reach all cells once, otherwise normalizedCounter is incorrect */
+ }
+
+ /* Build Decoding table */
+ {
+ U32 u;
+ for (u=0; u<tableSize; u++) {
+ U32 const symbol = tableDecode[u].baseValue;
+ U32 const nextState = symbolNext[symbol]++;
+ tableDecode[u].nbBits = (BYTE) (tableLog - BIT_highbit32(nextState) );
+ tableDecode[u].nextState = (U16) ( (nextState << tableDecode[u].nbBits) - tableSize);
+ assert(nbAdditionalBits[symbol] < 255);
+ tableDecode[u].nbAdditionalBits = (BYTE)nbAdditionalBits[symbol];
+ tableDecode[u].baseValue = baseValue[symbol];
+ }
+ }
+}
+
+/* Avoids the FORCE_INLINE of the _body() function. */
+static void ZSTD_buildFSETable_body_default(ZSTD_seqSymbol* dt,
+ const short* normalizedCounter, unsigned maxSymbolValue,
+ const U32* baseValue, const U32* nbAdditionalBits,
+ unsigned tableLog, void* wksp, size_t wkspSize)
+{
+ ZSTD_buildFSETable_body(dt, normalizedCounter, maxSymbolValue,
+ baseValue, nbAdditionalBits, tableLog, wksp, wkspSize);
+}
+
+#if DYNAMIC_BMI2
+TARGET_ATTRIBUTE("bmi2") static void ZSTD_buildFSETable_body_bmi2(ZSTD_seqSymbol* dt,
+ const short* normalizedCounter, unsigned maxSymbolValue,
+ const U32* baseValue, const U32* nbAdditionalBits,
+ unsigned tableLog, void* wksp, size_t wkspSize)
+{
+ ZSTD_buildFSETable_body(dt, normalizedCounter, maxSymbolValue,
+ baseValue, nbAdditionalBits, tableLog, wksp, wkspSize);
+}
+#endif
+
+void ZSTD_buildFSETable(ZSTD_seqSymbol* dt,
+ const short* normalizedCounter, unsigned maxSymbolValue,
+ const U32* baseValue, const U32* nbAdditionalBits,
+ unsigned tableLog, void* wksp, size_t wkspSize, int bmi2)
+{
+#if DYNAMIC_BMI2
+ if (bmi2) {
+ ZSTD_buildFSETable_body_bmi2(dt, normalizedCounter, maxSymbolValue,
+ baseValue, nbAdditionalBits, tableLog, wksp, wkspSize);
+ return;
+ }
+#endif
+ (void)bmi2;
+ ZSTD_buildFSETable_body_default(dt, normalizedCounter, maxSymbolValue,
+ baseValue, nbAdditionalBits, tableLog, wksp, wkspSize);
+}
+
+
+/*! ZSTD_buildSeqTable() :
+ * @return : nb bytes read from src,
+ * or an error code if it fails */
+static size_t ZSTD_buildSeqTable(ZSTD_seqSymbol* DTableSpace, const ZSTD_seqSymbol** DTablePtr,
+ symbolEncodingType_e type, unsigned max, U32 maxLog,
+ const void* src, size_t srcSize,
+ const U32* baseValue, const U32* nbAdditionalBits,
+ const ZSTD_seqSymbol* defaultTable, U32 flagRepeatTable,
+ int ddictIsCold, int nbSeq, U32* wksp, size_t wkspSize,
+ int bmi2)
+{
+ switch(type)
+ {
+ case set_rle :
+ RETURN_ERROR_IF(!srcSize, srcSize_wrong, "");
+ RETURN_ERROR_IF((*(const BYTE*)src) > max, corruption_detected, "");
+ { U32 const symbol = *(const BYTE*)src;
+ U32 const baseline = baseValue[symbol];
+ U32 const nbBits = nbAdditionalBits[symbol];
+ ZSTD_buildSeqTable_rle(DTableSpace, baseline, nbBits);
+ }
+ *DTablePtr = DTableSpace;
+ return 1;
+ case set_basic :
+ *DTablePtr = defaultTable;
+ return 0;
+ case set_repeat:
+ RETURN_ERROR_IF(!flagRepeatTable, corruption_detected, "");
+ /* prefetch FSE table if used */
+ if (ddictIsCold && (nbSeq > 24 /* heuristic */)) {
+ const void* const pStart = *DTablePtr;
+ size_t const pSize = sizeof(ZSTD_seqSymbol) * (SEQSYMBOL_TABLE_SIZE(maxLog));
+ PREFETCH_AREA(pStart, pSize);
+ }
+ return 0;
+ case set_compressed :
+ { unsigned tableLog;
+ S16 norm[MaxSeq+1];
+ size_t const headerSize = FSE_readNCount(norm, &max, &tableLog, src, srcSize);
+ RETURN_ERROR_IF(FSE_isError(headerSize), corruption_detected, "");
+ RETURN_ERROR_IF(tableLog > maxLog, corruption_detected, "");
+ ZSTD_buildFSETable(DTableSpace, norm, max, baseValue, nbAdditionalBits, tableLog, wksp, wkspSize, bmi2);
+ *DTablePtr = DTableSpace;
+ return headerSize;
+ }
+ default :
+ assert(0);
+ RETURN_ERROR(GENERIC, "impossible");
+ }
+}
+
+size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
+ const void* src, size_t srcSize)
+{
+ const BYTE* const istart = (const BYTE*)src;
+ const BYTE* const iend = istart + srcSize;
+ const BYTE* ip = istart;
+ int nbSeq;
+ DEBUGLOG(5, "ZSTD_decodeSeqHeaders");
+
+ /* check */
+ RETURN_ERROR_IF(srcSize < MIN_SEQUENCES_SIZE, srcSize_wrong, "");
+
+ /* SeqHead */
+ nbSeq = *ip++;
+ if (!nbSeq) {
+ *nbSeqPtr=0;
+ RETURN_ERROR_IF(srcSize != 1, srcSize_wrong, "");
+ return 1;
+ }
+ if (nbSeq > 0x7F) {
+ if (nbSeq == 0xFF) {
+ RETURN_ERROR_IF(ip+2 > iend, srcSize_wrong, "");
+ nbSeq = MEM_readLE16(ip) + LONGNBSEQ;
+ ip+=2;
+ } else {
+ RETURN_ERROR_IF(ip >= iend, srcSize_wrong, "");
+ nbSeq = ((nbSeq-0x80)<<8) + *ip++;
+ }
+ }
+ *nbSeqPtr = nbSeq;
+
+ /* FSE table descriptors */
+ RETURN_ERROR_IF(ip+1 > iend, srcSize_wrong, ""); /* minimum possible size: 1 byte for symbol encoding types */
+ { symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6);
+ symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3);
+ symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3);
+ ip++;
+
+ /* Build DTables */
+ { size_t const llhSize = ZSTD_buildSeqTable(dctx->entropy.LLTable, &dctx->LLTptr,
+ LLtype, MaxLL, LLFSELog,
+ ip, iend-ip,
+ LL_base, LL_bits,
+ LL_defaultDTable, dctx->fseEntropy,
+ dctx->ddictIsCold, nbSeq,
+ dctx->workspace, sizeof(dctx->workspace),
+ dctx->bmi2);
+ RETURN_ERROR_IF(ZSTD_isError(llhSize), corruption_detected, "ZSTD_buildSeqTable failed");
+ ip += llhSize;
+ }
+
+ { size_t const ofhSize = ZSTD_buildSeqTable(dctx->entropy.OFTable, &dctx->OFTptr,
+ OFtype, MaxOff, OffFSELog,
+ ip, iend-ip,
+ OF_base, OF_bits,
+ OF_defaultDTable, dctx->fseEntropy,
+ dctx->ddictIsCold, nbSeq,
+ dctx->workspace, sizeof(dctx->workspace),
+ dctx->bmi2);
+ RETURN_ERROR_IF(ZSTD_isError(ofhSize), corruption_detected, "ZSTD_buildSeqTable failed");
+ ip += ofhSize;
+ }
+
+ { size_t const mlhSize = ZSTD_buildSeqTable(dctx->entropy.MLTable, &dctx->MLTptr,
+ MLtype, MaxML, MLFSELog,
+ ip, iend-ip,
+ ML_base, ML_bits,
+ ML_defaultDTable, dctx->fseEntropy,
+ dctx->ddictIsCold, nbSeq,
+ dctx->workspace, sizeof(dctx->workspace),
+ dctx->bmi2);
+ RETURN_ERROR_IF(ZSTD_isError(mlhSize), corruption_detected, "ZSTD_buildSeqTable failed");
+ ip += mlhSize;
+ }
+ }
+
+ return ip-istart;
+}
+
+
+typedef struct {
+ size_t litLength;
+ size_t matchLength;
+ size_t offset;
+ const BYTE* match;
+} seq_t;
+
+typedef struct {
+ size_t state;
+ const ZSTD_seqSymbol* table;
+} ZSTD_fseState;
+
+typedef struct {
+ BIT_DStream_t DStream;
+ ZSTD_fseState stateLL;
+ ZSTD_fseState stateOffb;
+ ZSTD_fseState stateML;
+ size_t prevOffset[ZSTD_REP_NUM];
+ const BYTE* prefixStart;
+ const BYTE* dictEnd;
+ size_t pos;
+} seqState_t;
+
+/*! ZSTD_overlapCopy8() :
+ * Copies 8 bytes from ip to op and updates op and ip where ip <= op.
+ * If the offset is < 8 then the offset is spread to at least 8 bytes.
+ *
+ * Precondition: *ip <= *op
+ * Postcondition: *op - *op >= 8
+ */
+HINT_INLINE void ZSTD_overlapCopy8(BYTE** op, BYTE const** ip, size_t offset) {
+ assert(*ip <= *op);
+ if (offset < 8) {
+ /* close range match, overlap */
+ static const U32 dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 }; /* added */
+ static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 }; /* subtracted */
+ int const sub2 = dec64table[offset];
+ (*op)[0] = (*ip)[0];
+ (*op)[1] = (*ip)[1];
+ (*op)[2] = (*ip)[2];
+ (*op)[3] = (*ip)[3];
+ *ip += dec32table[offset];
+ ZSTD_copy4(*op+4, *ip);
+ *ip -= sub2;
+ } else {
+ ZSTD_copy8(*op, *ip);
+ }
+ *ip += 8;
+ *op += 8;
+ assert(*op - *ip >= 8);
+}
+
+/*! ZSTD_safecopy() :
+ * Specialized version of memcpy() that is allowed to READ up to WILDCOPY_OVERLENGTH past the input buffer
+ * and write up to 16 bytes past oend_w (op >= oend_w is allowed).
+ * This function is only called in the uncommon case where the sequence is near the end of the block. It
+ * should be fast for a single long sequence, but can be slow for several short sequences.
+ *
+ * @param ovtype controls the overlap detection
+ * - ZSTD_no_overlap: The source and destination are guaranteed to be at least WILDCOPY_VECLEN bytes apart.
+ * - ZSTD_overlap_src_before_dst: The src and dst may overlap and may be any distance apart.
+ * The src buffer must be before the dst buffer.
+ */
+static void ZSTD_safecopy(BYTE* op, BYTE* const oend_w, BYTE const* ip, ptrdiff_t length, ZSTD_overlap_e ovtype) {
+ ptrdiff_t const diff = op - ip;
+ BYTE* const oend = op + length;
+
+ assert((ovtype == ZSTD_no_overlap && (diff <= -8 || diff >= 8 || op >= oend_w)) ||
+ (ovtype == ZSTD_overlap_src_before_dst && diff >= 0));
+
+ if (length < 8) {
+ /* Handle short lengths. */
+ while (op < oend) *op++ = *ip++;
+ return;
+ }
+ if (ovtype == ZSTD_overlap_src_before_dst) {
+ /* Copy 8 bytes and ensure the offset >= 8 when there can be overlap. */
+ assert(length >= 8);
+ ZSTD_overlapCopy8(&op, &ip, diff);
+ assert(op - ip >= 8);
+ assert(op <= oend);
+ }
+
+ if (oend <= oend_w) {
+ /* No risk of overwrite. */
+ ZSTD_wildcopy(op, ip, length, ovtype);
+ return;
+ }
+ if (op <= oend_w) {
+ /* Wildcopy until we get close to the end. */
+ assert(oend > oend_w);
+ ZSTD_wildcopy(op, ip, oend_w - op, ovtype);
+ ip += oend_w - op;
+ op = oend_w;
+ }
+ /* Handle the leftovers. */
+ while (op < oend) *op++ = *ip++;
+}
+
+/* ZSTD_execSequenceEnd():
+ * This version handles cases that are near the end of the output buffer. It requires
+ * more careful checks to make sure there is no overflow. By separating out these hard
+ * and unlikely cases, we can speed up the common cases.
+ *
+ * NOTE: This function needs to be fast for a single long sequence, but doesn't need
+ * to be optimized for many small sequences, since those fall into ZSTD_execSequence().
+ */
+FORCE_NOINLINE
+size_t ZSTD_execSequenceEnd(BYTE* op,
+ BYTE* const oend, seq_t sequence,
+ const BYTE** litPtr, const BYTE* const litLimit,
+ const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
+{
+ BYTE* const oLitEnd = op + sequence.litLength;
+ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
+ const BYTE* const iLitEnd = *litPtr + sequence.litLength;
+ const BYTE* match = oLitEnd - sequence.offset;
+ BYTE* const oend_w = oend - WILDCOPY_OVERLENGTH;
+
+ /* bounds checks : careful of address space overflow in 32-bit mode */
+ RETURN_ERROR_IF(sequenceLength > (size_t)(oend - op), dstSize_tooSmall, "last match must fit within dstBuffer");
+ RETURN_ERROR_IF(sequence.litLength > (size_t)(litLimit - *litPtr), corruption_detected, "try to read beyond literal buffer");
+ assert(op < op + sequenceLength);
+ assert(oLitEnd < op + sequenceLength);
+
+ /* copy literals */
+ ZSTD_safecopy(op, oend_w, *litPtr, sequence.litLength, ZSTD_no_overlap);
+ op = oLitEnd;
+ *litPtr = iLitEnd;
+
+ /* copy Match */
+ if (sequence.offset > (size_t)(oLitEnd - prefixStart)) {
+ /* offset beyond prefix */
+ RETURN_ERROR_IF(sequence.offset > (size_t)(oLitEnd - virtualStart), corruption_detected, "");
+ match = dictEnd - (prefixStart-match);
+ if (match + sequence.matchLength <= dictEnd) {
+ ZSTD_memmove(oLitEnd, match, sequence.matchLength);
+ return sequenceLength;
+ }
+ /* span extDict & currentPrefixSegment */
+ { size_t const length1 = dictEnd - match;
+ ZSTD_memmove(oLitEnd, match, length1);
+ op = oLitEnd + length1;
+ sequence.matchLength -= length1;
+ match = prefixStart;
+ } }
+ ZSTD_safecopy(op, oend_w, match, sequence.matchLength, ZSTD_overlap_src_before_dst);
+ return sequenceLength;
+}
+
+HINT_INLINE
+size_t ZSTD_execSequence(BYTE* op,
+ BYTE* const oend, seq_t sequence,
+ const BYTE** litPtr, const BYTE* const litLimit,
+ const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
+{
+ BYTE* const oLitEnd = op + sequence.litLength;
+ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
+ BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */
+ BYTE* const oend_w = oend - WILDCOPY_OVERLENGTH; /* risk : address space underflow on oend=NULL */
+ const BYTE* const iLitEnd = *litPtr + sequence.litLength;
+ const BYTE* match = oLitEnd - sequence.offset;
+
+ assert(op != NULL /* Precondition */);
+ assert(oend_w < oend /* No underflow */);
+ /* Handle edge cases in a slow path:
+ * - Read beyond end of literals
+ * - Match end is within WILDCOPY_OVERLIMIT of oend
+ * - 32-bit mode and the match length overflows
+ */
+ if (UNLIKELY(
+ iLitEnd > litLimit ||
+ oMatchEnd > oend_w ||
+ (MEM_32bits() && (size_t)(oend - op) < sequenceLength + WILDCOPY_OVERLENGTH)))
+ return ZSTD_execSequenceEnd(op, oend, sequence, litPtr, litLimit, prefixStart, virtualStart, dictEnd);
+
+ /* Assumptions (everything else goes into ZSTD_execSequenceEnd()) */
+ assert(op <= oLitEnd /* No overflow */);
+ assert(oLitEnd < oMatchEnd /* Non-zero match & no overflow */);
+ assert(oMatchEnd <= oend /* No underflow */);
+ assert(iLitEnd <= litLimit /* Literal length is in bounds */);
+ assert(oLitEnd <= oend_w /* Can wildcopy literals */);
+ assert(oMatchEnd <= oend_w /* Can wildcopy matches */);
+
+ /* Copy Literals:
+ * Split out litLength <= 16 since it is nearly always true. +1.6% on gcc-9.
+ * We likely don't need the full 32-byte wildcopy.
+ */
+ assert(WILDCOPY_OVERLENGTH >= 16);
+ ZSTD_copy16(op, (*litPtr));
+ if (UNLIKELY(sequence.litLength > 16)) {
+ ZSTD_wildcopy(op+16, (*litPtr)+16, sequence.litLength-16, ZSTD_no_overlap);
+ }
+ op = oLitEnd;
+ *litPtr = iLitEnd; /* update for next sequence */
+
+ /* Copy Match */
+ if (sequence.offset > (size_t)(oLitEnd - prefixStart)) {
+ /* offset beyond prefix -> go into extDict */
+ RETURN_ERROR_IF(UNLIKELY(sequence.offset > (size_t)(oLitEnd - virtualStart)), corruption_detected, "");
+ match = dictEnd + (match - prefixStart);
+ if (match + sequence.matchLength <= dictEnd) {
+ ZSTD_memmove(oLitEnd, match, sequence.matchLength);
+ return sequenceLength;
+ }
+ /* span extDict & currentPrefixSegment */
+ { size_t const length1 = dictEnd - match;
+ ZSTD_memmove(oLitEnd, match, length1);
+ op = oLitEnd + length1;
+ sequence.matchLength -= length1;
+ match = prefixStart;
+ } }
+ /* Match within prefix of 1 or more bytes */
+ assert(op <= oMatchEnd);
+ assert(oMatchEnd <= oend_w);
+ assert(match >= prefixStart);
+ assert(sequence.matchLength >= 1);
+
+ /* Nearly all offsets are >= WILDCOPY_VECLEN bytes, which means we can use wildcopy
+ * without overlap checking.
+ */
+ if (LIKELY(sequence.offset >= WILDCOPY_VECLEN)) {
+ /* We bet on a full wildcopy for matches, since we expect matches to be
+ * longer than literals (in general). In silesia, ~10% of matches are longer
+ * than 16 bytes.
+ */
+ ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength, ZSTD_no_overlap);
+ return sequenceLength;
+ }
+ assert(sequence.offset < WILDCOPY_VECLEN);
+
+ /* Copy 8 bytes and spread the offset to be >= 8. */
+ ZSTD_overlapCopy8(&op, &match, sequence.offset);
+
+ /* If the match length is > 8 bytes, then continue with the wildcopy. */
+ if (sequence.matchLength > 8) {
+ assert(op < oMatchEnd);
+ ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8, ZSTD_overlap_src_before_dst);
+ }
+ return sequenceLength;
+}
+
+static void
+ZSTD_initFseState(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, const ZSTD_seqSymbol* dt)
+{
+ const void* ptr = dt;
+ const ZSTD_seqSymbol_header* const DTableH = (const ZSTD_seqSymbol_header*)ptr;
+ DStatePtr->state = BIT_readBits(bitD, DTableH->tableLog);
+ DEBUGLOG(6, "ZSTD_initFseState : val=%u using %u bits",
+ (U32)DStatePtr->state, DTableH->tableLog);
+ BIT_reloadDStream(bitD);
+ DStatePtr->table = dt + 1;
+}
+
+FORCE_INLINE_TEMPLATE void
+ZSTD_updateFseState(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD)
+{
+ ZSTD_seqSymbol const DInfo = DStatePtr->table[DStatePtr->state];
+ U32 const nbBits = DInfo.nbBits;
+ size_t const lowBits = BIT_readBits(bitD, nbBits);
+ DStatePtr->state = DInfo.nextState + lowBits;
+}
+
+FORCE_INLINE_TEMPLATE void
+ZSTD_updateFseStateWithDInfo(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, ZSTD_seqSymbol const DInfo)
+{
+ U32 const nbBits = DInfo.nbBits;
+ size_t const lowBits = BIT_readBits(bitD, nbBits);
+ DStatePtr->state = DInfo.nextState + lowBits;
+}
+
+/* We need to add at most (ZSTD_WINDOWLOG_MAX_32 - 1) bits to read the maximum
+ * offset bits. But we can only read at most (STREAM_ACCUMULATOR_MIN_32 - 1)
+ * bits before reloading. This value is the maximum number of bytes we read
+ * after reloading when we are decoding long offsets.
+ */
+#define LONG_OFFSETS_MAX_EXTRA_BITS_32 \
+ (ZSTD_WINDOWLOG_MAX_32 > STREAM_ACCUMULATOR_MIN_32 \
+ ? ZSTD_WINDOWLOG_MAX_32 - STREAM_ACCUMULATOR_MIN_32 \
+ : 0)
+
+typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset_e;
+typedef enum { ZSTD_p_noPrefetch=0, ZSTD_p_prefetch=1 } ZSTD_prefetch_e;
+
+FORCE_INLINE_TEMPLATE seq_t
+ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets, const ZSTD_prefetch_e prefetch)
+{
+ seq_t seq;
+ ZSTD_seqSymbol const llDInfo = seqState->stateLL.table[seqState->stateLL.state];
+ ZSTD_seqSymbol const mlDInfo = seqState->stateML.table[seqState->stateML.state];
+ ZSTD_seqSymbol const ofDInfo = seqState->stateOffb.table[seqState->stateOffb.state];
+ U32 const llBase = llDInfo.baseValue;
+ U32 const mlBase = mlDInfo.baseValue;
+ U32 const ofBase = ofDInfo.baseValue;
+ BYTE const llBits = llDInfo.nbAdditionalBits;
+ BYTE const mlBits = mlDInfo.nbAdditionalBits;
+ BYTE const ofBits = ofDInfo.nbAdditionalBits;
+ BYTE const totalBits = llBits+mlBits+ofBits;
+
+ /* sequence */
+ { size_t offset;
+ if (ofBits > 1) {
+ ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
+ ZSTD_STATIC_ASSERT(LONG_OFFSETS_MAX_EXTRA_BITS_32 == 5);
+ assert(ofBits <= MaxOff);
+ if (MEM_32bits() && longOffsets && (ofBits >= STREAM_ACCUMULATOR_MIN_32)) {
+ U32 const extraBits = ofBits - MIN(ofBits, 32 - seqState->DStream.bitsConsumed);
+ offset = ofBase + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
+ BIT_reloadDStream(&seqState->DStream);
+ if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits);
+ assert(extraBits <= LONG_OFFSETS_MAX_EXTRA_BITS_32); /* to avoid another reload */
+ } else {
+ offset = ofBase + BIT_readBitsFast(&seqState->DStream, ofBits/*>0*/); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
+ if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
+ }
+ seqState->prevOffset[2] = seqState->prevOffset[1];
+ seqState->prevOffset[1] = seqState->prevOffset[0];
+ seqState->prevOffset[0] = offset;
+ } else {
+ U32 const ll0 = (llBase == 0);
+ if (LIKELY((ofBits == 0))) {
+ if (LIKELY(!ll0))
+ offset = seqState->prevOffset[0];
+ else {
+ offset = seqState->prevOffset[1];
+ seqState->prevOffset[1] = seqState->prevOffset[0];
+ seqState->prevOffset[0] = offset;
+ }
+ } else {
+ offset = ofBase + ll0 + BIT_readBitsFast(&seqState->DStream, 1);
+ { size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
+ temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
+ if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1];
+ seqState->prevOffset[1] = seqState->prevOffset[0];
+ seqState->prevOffset[0] = offset = temp;
+ } } }
+ seq.offset = offset;
+ }
+
+ seq.matchLength = mlBase;
+ if (mlBits > 0)
+ seq.matchLength += BIT_readBitsFast(&seqState->DStream, mlBits/*>0*/);
+
+ if (MEM_32bits() && (mlBits+llBits >= STREAM_ACCUMULATOR_MIN_32-LONG_OFFSETS_MAX_EXTRA_BITS_32))
+ BIT_reloadDStream(&seqState->DStream);
+ if (MEM_64bits() && UNLIKELY(totalBits >= STREAM_ACCUMULATOR_MIN_64-(LLFSELog+MLFSELog+OffFSELog)))
+ BIT_reloadDStream(&seqState->DStream);
+ /* Ensure there are enough bits to read the rest of data in 64-bit mode. */
+ ZSTD_STATIC_ASSERT(16+LLFSELog+MLFSELog+OffFSELog < STREAM_ACCUMULATOR_MIN_64);
+
+ seq.litLength = llBase;
+ if (llBits > 0)
+ seq.litLength += BIT_readBitsFast(&seqState->DStream, llBits/*>0*/);
+
+ if (MEM_32bits())
+ BIT_reloadDStream(&seqState->DStream);
+
+ DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u",
+ (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
+
+ if (prefetch == ZSTD_p_prefetch) {
+ size_t const pos = seqState->pos + seq.litLength;
+ const BYTE* const matchBase = (seq.offset > pos) ? seqState->dictEnd : seqState->prefixStart;
+ seq.match = matchBase + pos - seq.offset; /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
+ * No consequence though : no memory access will occur, offset is only used for prefetching */
+ seqState->pos = pos + seq.matchLength;
+ }
+
+ /* ANS state update
+ * gcc-9.0.0 does 2.5% worse with ZSTD_updateFseStateWithDInfo().
+ * clang-9.2.0 does 7% worse with ZSTD_updateFseState().
+ * Naturally it seems like ZSTD_updateFseStateWithDInfo() should be the
+ * better option, so it is the default for other compilers. But, if you
+ * measure that it is worse, please put up a pull request.
+ */
+ {
+#if !defined(__clang__)
+ const int kUseUpdateFseState = 1;
+#else
+ const int kUseUpdateFseState = 0;
+#endif
+ if (kUseUpdateFseState) {
+ ZSTD_updateFseState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */
+ ZSTD_updateFseState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */
+ if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
+ ZSTD_updateFseState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
+ } else {
+ ZSTD_updateFseStateWithDInfo(&seqState->stateLL, &seqState->DStream, llDInfo); /* <= 9 bits */
+ ZSTD_updateFseStateWithDInfo(&seqState->stateML, &seqState->DStream, mlDInfo); /* <= 9 bits */
+ if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
+ ZSTD_updateFseStateWithDInfo(&seqState->stateOffb, &seqState->DStream, ofDInfo); /* <= 8 bits */
+ }
+ }
+
+ return seq;
+}
+
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+MEM_STATIC int ZSTD_dictionaryIsActive(ZSTD_DCtx const* dctx, BYTE const* prefixStart, BYTE const* oLitEnd)
+{
+ size_t const windowSize = dctx->fParams.windowSize;
+ /* No dictionary used. */
+ if (dctx->dictContentEndForFuzzing == NULL) return 0;
+ /* Dictionary is our prefix. */
+ if (prefixStart == dctx->dictContentBeginForFuzzing) return 1;
+ /* Dictionary is not our ext-dict. */
+ if (dctx->dictEnd != dctx->dictContentEndForFuzzing) return 0;
+ /* Dictionary is not within our window size. */
+ if ((size_t)(oLitEnd - prefixStart) >= windowSize) return 0;
+ /* Dictionary is active. */
+ return 1;
+}
+
+MEM_STATIC void ZSTD_assertValidSequence(
+ ZSTD_DCtx const* dctx,
+ BYTE const* op, BYTE const* oend,
+ seq_t const seq,
+ BYTE const* prefixStart, BYTE const* virtualStart)
+{
+#if DEBUGLEVEL >= 1
+ size_t const windowSize = dctx->fParams.windowSize;
+ size_t const sequenceSize = seq.litLength + seq.matchLength;
+ BYTE const* const oLitEnd = op + seq.litLength;
+ DEBUGLOG(6, "Checking sequence: litL=%u matchL=%u offset=%u",
+ (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
+ assert(op <= oend);
+ assert((size_t)(oend - op) >= sequenceSize);
+ assert(sequenceSize <= ZSTD_BLOCKSIZE_MAX);
+ if (ZSTD_dictionaryIsActive(dctx, prefixStart, oLitEnd)) {
+ size_t const dictSize = (size_t)((char const*)dctx->dictContentEndForFuzzing - (char const*)dctx->dictContentBeginForFuzzing);
+ /* Offset must be within the dictionary. */
+ assert(seq.offset <= (size_t)(oLitEnd - virtualStart));
+ assert(seq.offset <= windowSize + dictSize);
+ } else {
+ /* Offset must be within our window. */
+ assert(seq.offset <= windowSize);
+ }
+#else
+ (void)dctx, (void)op, (void)oend, (void)seq, (void)prefixStart, (void)virtualStart;
+#endif
+}
+#endif
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
+FORCE_INLINE_TEMPLATE size_t
+DONT_VECTORIZE
+ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ const BYTE* ip = (const BYTE*)seqStart;
+ const BYTE* const iend = ip + seqSize;
+ BYTE* const ostart = (BYTE*)dst;
+ BYTE* const oend = ostart + maxDstSize;
+ BYTE* op = ostart;
+ const BYTE* litPtr = dctx->litPtr;
+ const BYTE* const litEnd = litPtr + dctx->litSize;
+ const BYTE* const prefixStart = (const BYTE*) (dctx->prefixStart);
+ const BYTE* const vBase = (const BYTE*) (dctx->virtualStart);
+ const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
+ DEBUGLOG(5, "ZSTD_decompressSequences_body");
+ (void)frame;
+
+ /* Regen sequences */
+ if (nbSeq) {
+ seqState_t seqState;
+ size_t error = 0;
+ dctx->fseEntropy = 1;
+ { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
+ RETURN_ERROR_IF(
+ ERR_isError(BIT_initDStream(&seqState.DStream, ip, iend-ip)),
+ corruption_detected, "");
+ ZSTD_initFseState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr);
+ ZSTD_initFseState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr);
+ ZSTD_initFseState(&seqState.stateML, &seqState.DStream, dctx->MLTptr);
+ assert(dst != NULL);
+
+ ZSTD_STATIC_ASSERT(
+ BIT_DStream_unfinished < BIT_DStream_completed &&
+ BIT_DStream_endOfBuffer < BIT_DStream_completed &&
+ BIT_DStream_completed < BIT_DStream_overflow);
+
+#if defined(__x86_64__)
+ /* Align the decompression loop to 32 + 16 bytes.
+ *
+ * zstd compiled with gcc-9 on an Intel i9-9900k shows 10% decompression
+ * speed swings based on the alignment of the decompression loop. This
+ * performance swing is caused by parts of the decompression loop falling
+ * out of the DSB. The entire decompression loop should fit in the DSB,
+ * when it can't we get much worse performance. You can measure if you've
+ * hit the good case or the bad case with this perf command for some
+ * compressed file test.zst:
+ *
+ * perf stat -e cycles -e instructions -e idq.all_dsb_cycles_any_uops \
+ * -e idq.all_mite_cycles_any_uops -- ./zstd -tq test.zst
+ *
+ * If you see most cycles served out of the MITE you've hit the bad case.
+ * If you see most cycles served out of the DSB you've hit the good case.
+ * If it is pretty even then you may be in an okay case.
+ *
+ * I've been able to reproduce this issue on the following CPUs:
+ * - Kabylake: Macbook Pro (15-inch, 2019) 2.4 GHz Intel Core i9
+ * Use Instruments->Counters to get DSB/MITE cycles.
+ * I never got performance swings, but I was able to
+ * go from the good case of mostly DSB to half of the
+ * cycles served from MITE.
+ * - Coffeelake: Intel i9-9900k
+ *
+ * I haven't been able to reproduce the instability or DSB misses on any
+ * of the following CPUS:
+ * - Haswell
+ * - Broadwell: Intel(R) Xeon(R) CPU E5-2680 v4 @ 2.40GH
+ * - Skylake
+ *
+ * If you are seeing performance stability this script can help test.
+ * It tests on 4 commits in zstd where I saw performance change.
+ *
+ * https://gist.github.com/terrelln/9889fc06a423fd5ca6e99351564473f4
+ */
+ __asm__(".p2align 5");
+ __asm__("nop");
+ __asm__(".p2align 4");
+#endif
+ for ( ; ; ) {
+ seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_noPrefetch);
+ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, prefixStart, vBase, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequence, prefixStart, vBase);
+#endif
+ DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
+ BIT_reloadDStream(&(seqState.DStream));
+ op += oneSeqSize;
+ /* gcc and clang both don't like early returns in this loop.
+ * Instead break and check for an error at the end of the loop.
+ */
+ if (UNLIKELY(ZSTD_isError(oneSeqSize))) {
+ error = oneSeqSize;
+ break;
+ }
+ if (UNLIKELY(!--nbSeq)) break;
+ }
+
+ /* check if reached exact end */
+ DEBUGLOG(5, "ZSTD_decompressSequences_body: after decode loop, remaining nbSeq : %i", nbSeq);
+ if (ZSTD_isError(error)) return error;
+ RETURN_ERROR_IF(nbSeq, corruption_detected, "");
+ RETURN_ERROR_IF(BIT_reloadDStream(&seqState.DStream) < BIT_DStream_completed, corruption_detected, "");
+ /* save reps for next block */
+ { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); }
+ }
+
+ /* last literal segment */
+ { size_t const lastLLSize = litEnd - litPtr;
+ RETURN_ERROR_IF(lastLLSize > (size_t)(oend-op), dstSize_tooSmall, "");
+ if (op != NULL) {
+ ZSTD_memcpy(op, litPtr, lastLLSize);
+ op += lastLLSize;
+ }
+ }
+
+ return op-ostart;
+}
+
+static size_t
+ZSTD_decompressSequences_default(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ return ZSTD_decompressSequences_body(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
+FORCE_INLINE_TEMPLATE size_t
+ZSTD_decompressSequencesLong_body(
+ ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ const BYTE* ip = (const BYTE*)seqStart;
+ const BYTE* const iend = ip + seqSize;
+ BYTE* const ostart = (BYTE*)dst;
+ BYTE* const oend = ostart + maxDstSize;
+ BYTE* op = ostart;
+ const BYTE* litPtr = dctx->litPtr;
+ const BYTE* const litEnd = litPtr + dctx->litSize;
+ const BYTE* const prefixStart = (const BYTE*) (dctx->prefixStart);
+ const BYTE* const dictStart = (const BYTE*) (dctx->virtualStart);
+ const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
+ (void)frame;
+
+ /* Regen sequences */
+ if (nbSeq) {
+#define STORED_SEQS 4
+#define STORED_SEQS_MASK (STORED_SEQS-1)
+#define ADVANCED_SEQS 4
+ seq_t sequences[STORED_SEQS];
+ int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS);
+ seqState_t seqState;
+ int seqNb;
+ dctx->fseEntropy = 1;
+ { int i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
+ seqState.prefixStart = prefixStart;
+ seqState.pos = (size_t)(op-prefixStart);
+ seqState.dictEnd = dictEnd;
+ assert(dst != NULL);
+ assert(iend >= ip);
+ RETURN_ERROR_IF(
+ ERR_isError(BIT_initDStream(&seqState.DStream, ip, iend-ip)),
+ corruption_detected, "");
+ ZSTD_initFseState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr);
+ ZSTD_initFseState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr);
+ ZSTD_initFseState(&seqState.stateML, &seqState.DStream, dctx->MLTptr);
+
+ /* prepare in advance */
+ for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && (seqNb<seqAdvance); seqNb++) {
+ sequences[seqNb] = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_prefetch);
+ PREFETCH_L1(sequences[seqNb].match); PREFETCH_L1(sequences[seqNb].match + sequences[seqNb].matchLength - 1); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
+ }
+ RETURN_ERROR_IF(seqNb<seqAdvance, corruption_detected, "");
+
+ /* decode and decompress */
+ for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && (seqNb<nbSeq) ; seqNb++) {
+ seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_prefetch);
+ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[(seqNb-ADVANCED_SEQS) & STORED_SEQS_MASK], &litPtr, litEnd, prefixStart, dictStart, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[(seqNb-ADVANCED_SEQS) & STORED_SEQS_MASK], prefixStart, dictStart);
+#endif
+ if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
+ PREFETCH_L1(sequence.match); PREFETCH_L1(sequence.match + sequence.matchLength - 1); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
+ sequences[seqNb & STORED_SEQS_MASK] = sequence;
+ op += oneSeqSize;
+ }
+ RETURN_ERROR_IF(seqNb<nbSeq, corruption_detected, "");
+
+ /* finish queue */
+ seqNb -= seqAdvance;
+ for ( ; seqNb<nbSeq ; seqNb++) {
+ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[seqNb&STORED_SEQS_MASK], &litPtr, litEnd, prefixStart, dictStart, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[seqNb&STORED_SEQS_MASK], prefixStart, dictStart);
+#endif
+ if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
+ op += oneSeqSize;
+ }
+
+ /* save reps for next block */
+ { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); }
+ }
+
+ /* last literal segment */
+ { size_t const lastLLSize = litEnd - litPtr;
+ RETURN_ERROR_IF(lastLLSize > (size_t)(oend-op), dstSize_tooSmall, "");
+ if (op != NULL) {
+ ZSTD_memcpy(op, litPtr, lastLLSize);
+ op += lastLLSize;
+ }
+ }
+
+ return op-ostart;
+}
+
+static size_t
+ZSTD_decompressSequencesLong_default(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ return ZSTD_decompressSequencesLong_body(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT */
+
+
+
+#if DYNAMIC_BMI2
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
+static TARGET_ATTRIBUTE("bmi2") size_t
+DONT_VECTORIZE
+ZSTD_decompressSequences_bmi2(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ return ZSTD_decompressSequences_body(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
+static TARGET_ATTRIBUTE("bmi2") size_t
+ZSTD_decompressSequencesLong_bmi2(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ return ZSTD_decompressSequencesLong_body(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT */
+
+#endif /* DYNAMIC_BMI2 */
+
+typedef size_t (*ZSTD_decompressSequences_t)(
+ ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame);
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
+static size_t
+ZSTD_decompressSequences(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ DEBUGLOG(5, "ZSTD_decompressSequences");
+#if DYNAMIC_BMI2
+ if (dctx->bmi2) {
+ return ZSTD_decompressSequences_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+ }
+#endif
+ return ZSTD_decompressSequences_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
+
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
+/* ZSTD_decompressSequencesLong() :
+ * decompression function triggered when a minimum share of offsets is considered "long",
+ * aka out of cache.
+ * note : "long" definition seems overloaded here, sometimes meaning "wider than bitstream register", and sometimes meaning "farther than memory cache distance".
+ * This function will try to mitigate main memory latency through the use of prefetching */
+static size_t
+ZSTD_decompressSequencesLong(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ DEBUGLOG(5, "ZSTD_decompressSequencesLong");
+#if DYNAMIC_BMI2
+ if (dctx->bmi2) {
+ return ZSTD_decompressSequencesLong_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+ }
+#endif
+ return ZSTD_decompressSequencesLong_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT */
+
+
+
+#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
+ !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
+/* ZSTD_getLongOffsetsShare() :
+ * condition : offTable must be valid
+ * @return : "share" of long offsets (arbitrarily defined as > (1<<23))
+ * compared to maximum possible of (1<<OffFSELog) */
+static unsigned
+ZSTD_getLongOffsetsShare(const ZSTD_seqSymbol* offTable)
+{
+ const void* ptr = offTable;
+ U32 const tableLog = ((const ZSTD_seqSymbol_header*)ptr)[0].tableLog;
+ const ZSTD_seqSymbol* table = offTable + 1;
+ U32 const max = 1 << tableLog;
+ U32 u, total = 0;
+ DEBUGLOG(5, "ZSTD_getLongOffsetsShare: (tableLog=%u)", tableLog);
+
+ assert(max <= (1 << OffFSELog)); /* max not too large */
+ for (u=0; u<max; u++) {
+ if (table[u].nbAdditionalBits > 22) total += 1;
+ }
+
+ assert(tableLog <= OffFSELog);
+ total <<= (OffFSELog - tableLog); /* scale to OffFSELog */
+
+ return total;
+}
+#endif
+
+size_t
+ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize, const int frame)
+{ /* blockType == blockCompressed */
+ const BYTE* ip = (const BYTE*)src;
+ /* isLongOffset must be true if there are long offsets.
+ * Offsets are long if they are larger than 2^STREAM_ACCUMULATOR_MIN.
+ * We don't expect that to be the case in 64-bit mode.
+ * In block mode, window size is not known, so we have to be conservative.
+ * (note: but it could be evaluated from current-lowLimit)
+ */
+ ZSTD_longOffset_e const isLongOffset = (ZSTD_longOffset_e)(MEM_32bits() && (!frame || (dctx->fParams.windowSize > (1ULL << STREAM_ACCUMULATOR_MIN))));
+ DEBUGLOG(5, "ZSTD_decompressBlock_internal (size : %u)", (U32)srcSize);
+
+ RETURN_ERROR_IF(srcSize >= ZSTD_BLOCKSIZE_MAX, srcSize_wrong, "");
+
+ /* Decode literals section */
+ { size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
+ DEBUGLOG(5, "ZSTD_decodeLiteralsBlock : %u", (U32)litCSize);
+ if (ZSTD_isError(litCSize)) return litCSize;
+ ip += litCSize;
+ srcSize -= litCSize;
+ }
+
+ /* Build Decoding Tables */
+ {
+ /* These macros control at build-time which decompressor implementation
+ * we use. If neither is defined, we do some inspection and dispatch at
+ * runtime.
+ */
+#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
+ !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
+ int usePrefetchDecoder = dctx->ddictIsCold;
+#endif
+ int nbSeq;
+ size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, srcSize);
+ if (ZSTD_isError(seqHSize)) return seqHSize;
+ ip += seqHSize;
+ srcSize -= seqHSize;
+
+ RETURN_ERROR_IF(dst == NULL && nbSeq > 0, dstSize_tooSmall, "NULL not handled");
+
+#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
+ !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
+ if ( !usePrefetchDecoder
+ && (!frame || (dctx->fParams.windowSize > (1<<24)))
+ && (nbSeq>ADVANCED_SEQS) ) { /* could probably use a larger nbSeq limit */
+ U32 const shareLongOffsets = ZSTD_getLongOffsetsShare(dctx->OFTptr);
+ U32 const minShare = MEM_64bits() ? 7 : 20; /* heuristic values, correspond to 2.73% and 7.81% */
+ usePrefetchDecoder = (shareLongOffsets >= minShare);
+ }
+#endif
+
+ dctx->ddictIsCold = 0;
+
+#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
+ !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
+ if (usePrefetchDecoder)
+#endif
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
+ return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
+#endif
+
+#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
+ /* else */
+ return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
+#endif
+ }
+}
+
+
+void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst, size_t dstSize)
+{
+ if (dst != dctx->previousDstEnd && dstSize > 0) { /* not contiguous */
+ dctx->dictEnd = dctx->previousDstEnd;
+ dctx->virtualStart = (const char*)dst - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->prefixStart));
+ dctx->prefixStart = dst;
+ dctx->previousDstEnd = dst;
+ }
+}
+
+
+size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize)
+{
+ size_t dSize;
+ ZSTD_checkContinuity(dctx, dst, dstCapacity);
+ dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 0);
+ dctx->previousDstEnd = (char*)dst + dSize;
+ return dSize;
+}
diff --git a/lib/zstd/decompress/zstd_decompress_block.h b/lib/zstd/decompress/zstd_decompress_block.h
new file mode 100644
index 000000000000..e7f5f6689459
--- /dev/null
+++ b/lib/zstd/decompress/zstd_decompress_block.h
@@ -0,0 +1,62 @@
+/*
+ * 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.
+ */
+
+
+#ifndef ZSTD_DEC_BLOCK_H
+#define ZSTD_DEC_BLOCK_H
+
+/*-*******************************************************
+ * Dependencies
+ *********************************************************/
+#include "../common/zstd_deps.h" /* size_t */
+#include <linux/zstd.h> /* DCtx, and some public functions */
+#include "../common/zstd_internal.h" /* blockProperties_t, and some public functions */
+#include "zstd_decompress_internal.h" /* ZSTD_seqSymbol */
+
+
+/* === Prototypes === */
+
+/* note: prototypes already published within `zstd.h` :
+ * ZSTD_decompressBlock()
+ */
+
+/* note: prototypes already published within `zstd_internal.h` :
+ * ZSTD_getcBlockSize()
+ * ZSTD_decodeSeqHeaders()
+ */
+
+
+/* ZSTD_decompressBlock_internal() :
+ * decompress block, starting at `src`,
+ * into destination buffer `dst`.
+ * @return : decompressed block size,
+ * or an error code (which can be tested using ZSTD_isError())
+ */
+size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
+ void* dst, size_t dstCapacity,
+ const void* src, size_t srcSize, const int frame);
+
+/* ZSTD_buildFSETable() :
+ * generate FSE decoding table for one symbol (ll, ml or off)
+ * this function must be called with valid parameters only
+ * (dt is large enough, normalizedCounter distribution total is a power of 2, max is within range, etc.)
+ * in which case it cannot fail.
+ * The workspace must be 4-byte aligned and at least ZSTD_BUILD_FSE_TABLE_WKSP_SIZE bytes, which is
+ * defined in zstd_decompress_internal.h.
+ * Internal use only.
+ */
+void ZSTD_buildFSETable(ZSTD_seqSymbol* dt,
+ const short* normalizedCounter, unsigned maxSymbolValue,
+ const U32* baseValue, const U32* nbAdditionalBits,
+ unsigned tableLog, void* wksp, size_t wkspSize,
+ int bmi2);
+
+
+#endif /* ZSTD_DEC_BLOCK_H */
diff --git a/lib/zstd/decompress/zstd_decompress_internal.h b/lib/zstd/decompress/zstd_decompress_internal.h
new file mode 100644
index 000000000000..4b9052f68755
--- /dev/null
+++ b/lib/zstd/decompress/zstd_decompress_internal.h
@@ -0,0 +1,202 @@
+/*
+ * 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.
+ */
+
+
+/* zstd_decompress_internal:
+ * objects and definitions shared within lib/decompress modules */
+
+ #ifndef ZSTD_DECOMPRESS_INTERNAL_H
+ #define ZSTD_DECOMPRESS_INTERNAL_H
+
+
+/*-*******************************************************
+ * Dependencies
+ *********************************************************/
+#include "../common/mem.h" /* BYTE, U16, U32 */
+#include "../common/zstd_internal.h" /* ZSTD_seqSymbol */
+
+
+
+/*-*******************************************************
+ * Constants
+ *********************************************************/
+static UNUSED_ATTR const U32 LL_base[MaxLL+1] = {
+ 0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 18, 20, 22, 24, 28, 32, 40,
+ 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000,
+ 0x2000, 0x4000, 0x8000, 0x10000 };
+
+static UNUSED_ATTR const U32 OF_base[MaxOff+1] = {
+ 0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D,
+ 0xFD, 0x1FD, 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD,
+ 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD,
+ 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD, 0x1FFFFFFD, 0x3FFFFFFD, 0x7FFFFFFD };
+
+static UNUSED_ATTR const U32 OF_bits[MaxOff+1] = {
+ 0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23,
+ 24, 25, 26, 27, 28, 29, 30, 31 };
+
+static UNUSED_ATTR const U32 ML_base[MaxML+1] = {
+ 3, 4, 5, 6, 7, 8, 9, 10,
+ 11, 12, 13, 14, 15, 16, 17, 18,
+ 19, 20, 21, 22, 23, 24, 25, 26,
+ 27, 28, 29, 30, 31, 32, 33, 34,
+ 35, 37, 39, 41, 43, 47, 51, 59,
+ 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803,
+ 0x1003, 0x2003, 0x4003, 0x8003, 0x10003 };
+
+
+/*-*******************************************************
+ * Decompression types
+ *********************************************************/
+ typedef struct {
+ U32 fastMode;
+ U32 tableLog;
+ } ZSTD_seqSymbol_header;
+
+ typedef struct {
+ U16 nextState;
+ BYTE nbAdditionalBits;
+ BYTE nbBits;
+ U32 baseValue;
+ } ZSTD_seqSymbol;
+
+ #define SEQSYMBOL_TABLE_SIZE(log) (1 + (1 << (log)))
+
+#define ZSTD_BUILD_FSE_TABLE_WKSP_SIZE (sizeof(S16) * (MaxSeq + 1) + (1u << MaxFSELog) + sizeof(U64))
+#define ZSTD_BUILD_FSE_TABLE_WKSP_SIZE_U32 ((ZSTD_BUILD_FSE_TABLE_WKSP_SIZE + sizeof(U32) - 1) / sizeof(U32))
+
+typedef struct {
+ ZSTD_seqSymbol LLTable[SEQSYMBOL_TABLE_SIZE(LLFSELog)]; /* Note : Space reserved for FSE Tables */
+ ZSTD_seqSymbol OFTable[SEQSYMBOL_TABLE_SIZE(OffFSELog)]; /* is also used as temporary workspace while building hufTable during DDict creation */
+ ZSTD_seqSymbol MLTable[SEQSYMBOL_TABLE_SIZE(MLFSELog)]; /* and therefore must be at least HUF_DECOMPRESS_WORKSPACE_SIZE large */
+ HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */
+ U32 rep[ZSTD_REP_NUM];
+ U32 workspace[ZSTD_BUILD_FSE_TABLE_WKSP_SIZE_U32];
+} ZSTD_entropyDTables_t;
+
+typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
+ ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock,
+ ZSTDds_decompressLastBlock, ZSTDds_checkChecksum,
+ ZSTDds_decodeSkippableHeader, ZSTDds_skipFrame } ZSTD_dStage;
+
+typedef enum { zdss_init=0, zdss_loadHeader,
+ zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
+
+typedef enum {
+ ZSTD_use_indefinitely = -1, /* Use the dictionary indefinitely */
+ ZSTD_dont_use = 0, /* Do not use the dictionary (if one exists free it) */
+ ZSTD_use_once = 1 /* Use the dictionary once and set to ZSTD_dont_use */
+} ZSTD_dictUses_e;
+
+/* Hashset for storing references to multiple ZSTD_DDict within ZSTD_DCtx */
+typedef struct {
+ const ZSTD_DDict** ddictPtrTable;
+ size_t ddictPtrTableSize;
+ size_t ddictPtrCount;
+} ZSTD_DDictHashSet;
+
+struct ZSTD_DCtx_s
+{
+ const ZSTD_seqSymbol* LLTptr;
+ const ZSTD_seqSymbol* MLTptr;
+ const ZSTD_seqSymbol* OFTptr;
+ const HUF_DTable* HUFptr;
+ ZSTD_entropyDTables_t entropy;
+ U32 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32]; /* space needed when building huffman tables */
+ const void* previousDstEnd; /* detect continuity */
+ const void* prefixStart; /* start of current segment */
+ const void* virtualStart; /* virtual start of previous segment if it was just before current one */
+ const void* dictEnd; /* end of previous segment */
+ size_t expected;
+ ZSTD_frameHeader fParams;
+ U64 processedCSize;
+ U64 decodedSize;
+ blockType_e bType; /* used in ZSTD_decompressContinue(), store blockType between block header decoding and block decompression stages */
+ ZSTD_dStage stage;
+ U32 litEntropy;
+ U32 fseEntropy;
+ struct xxh64_state xxhState;
+ size_t headerSize;
+ ZSTD_format_e format;
+ ZSTD_forceIgnoreChecksum_e forceIgnoreChecksum; /* User specified: if == 1, will ignore checksums in compressed frame. Default == 0 */
+ U32 validateChecksum; /* if == 1, will validate checksum. Is == 1 if (fParams.checksumFlag == 1) and (forceIgnoreChecksum == 0). */
+ const BYTE* litPtr;
+ ZSTD_customMem customMem;
+ size_t litSize;
+ size_t rleSize;
+ size_t staticSize;
+ int bmi2; /* == 1 if the CPU supports BMI2 and 0 otherwise. CPU support is determined dynamically once per context lifetime. */
+
+ /* dictionary */
+ ZSTD_DDict* ddictLocal;
+ const ZSTD_DDict* ddict; /* set by ZSTD_initDStream_usingDDict(), or ZSTD_DCtx_refDDict() */
+ U32 dictID;
+ int ddictIsCold; /* if == 1 : dictionary is "new" for working context, and presumed "cold" (not in cpu cache) */
+ ZSTD_dictUses_e dictUses;
+ ZSTD_DDictHashSet* ddictSet; /* Hash set for multiple ddicts */
+ ZSTD_refMultipleDDicts_e refMultipleDDicts; /* User specified: if == 1, will allow references to multiple DDicts. Default == 0 (disabled) */
+
+ /* streaming */
+ ZSTD_dStreamStage streamStage;
+ char* inBuff;
+ size_t inBuffSize;
+ size_t inPos;
+ size_t maxWindowSize;
+ char* outBuff;
+ size_t outBuffSize;
+ size_t outStart;
+ size_t outEnd;
+ size_t lhSize;
+ void* legacyContext;
+ U32 previousLegacyVersion;
+ U32 legacyVersion;
+ U32 hostageByte;
+ int noForwardProgress;
+ ZSTD_bufferMode_e outBufferMode;
+ ZSTD_outBuffer expectedOutBuffer;
+
+ /* workspace */
+ BYTE litBuffer[ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH];
+ BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
+
+ size_t oversizedDuration;
+
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ void const* dictContentBeginForFuzzing;
+ void const* dictContentEndForFuzzing;
+#endif
+
+ /* Tracing */
+}; /* typedef'd to ZSTD_DCtx within "zstd.h" */
+
+
+/*-*******************************************************
+ * Shared internal functions
+ *********************************************************/
+
+/*! ZSTD_loadDEntropy() :
+ * dict : must point at beginning of a valid zstd dictionary.
+ * @return : size of dictionary header (size of magic number + dict ID + entropy tables) */
+size_t ZSTD_loadDEntropy(ZSTD_entropyDTables_t* entropy,
+ const void* const dict, size_t const dictSize);
+
+/*! ZSTD_checkContinuity() :
+ * check if next `dst` follows previous position, where decompression ended.
+ * If yes, do nothing (continue on current segment).
+ * If not, classify previous segment as "external dictionary", and start a new segment.
+ * This function cannot fail. */
+void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst, size_t dstSize);
+
+
+#endif /* ZSTD_DECOMPRESS_INTERNAL_H */
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-11-23 08:58:31 +0000