ReactOS 0.4.15-dev-8119-g4fb2fdb
zstd_decompress_block.h File Reference
#include <stddef.h>
#include "zstd.h"
#include "zstd_internal.h"
#include "zstd_decompress_internal.h"
Include dependency graph for zstd_decompress_block.h:
This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Functions

size_t ZSTD_decompressBlock_internal (ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const int frame)
 
void ZSTD_buildFSETable (ZSTD_seqSymbol *dt, const short *normalizedCounter, unsigned maxSymbolValue, const U32 *baseValue, const U32 *nbAdditionalBits, unsigned tableLog)
 

Function Documentation

◆ ZSTD_buildFSETable()

void ZSTD_buildFSETable ( ZSTD_seqSymbol dt,
const short normalizedCounter,
unsigned  maxSymbolValue,
const U32 baseValue,
const U32 nbAdditionalBits,
unsigned  tableLog 
)

Definition at line 368 of file zstd_decompress_block.c.

372{
373 ZSTD_seqSymbol* const tableDecode = dt+1;
374 U16 symbolNext[MaxSeq+1];
375
376 U32 const maxSV1 = maxSymbolValue + 1;
377 U32 const tableSize = 1 << tableLog;
378 U32 highThreshold = tableSize-1;
379
380 /* Sanity Checks */
381 assert(maxSymbolValue <= MaxSeq);
382 assert(tableLog <= MaxFSELog);
383
384 /* Init, lay down lowprob symbols */
385 { ZSTD_seqSymbol_header DTableH;
386 DTableH.tableLog = tableLog;
387 DTableH.fastMode = 1;
388 { S16 const largeLimit= (S16)(1 << (tableLog-1));
389 U32 s;
390 for (s=0; s<maxSV1; s++) {
391 if (normalizedCounter[s]==-1) {
392 tableDecode[highThreshold--].baseValue = s;
393 symbolNext[s] = 1;
394 } else {
395 if (normalizedCounter[s] >= largeLimit) DTableH.fastMode=0;
396 assert(normalizedCounter[s]>=0);
397 symbolNext[s] = (U16)normalizedCounter[s];
398 } } }
399 memcpy(dt, &DTableH, sizeof(DTableH));
400 }
401
402 /* Spread symbols */
403 { U32 const tableMask = tableSize-1;
404 U32 const step = FSE_TABLESTEP(tableSize);
405 U32 s, position = 0;
406 for (s=0; s<maxSV1; s++) {
407 int i;
408 for (i=0; i<normalizedCounter[s]; i++) {
409 tableDecode[position].baseValue = s;
410 position = (position + step) & tableMask;
411 while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */
412 } }
413 assert(position == 0); /* position must reach all cells once, otherwise normalizedCounter is incorrect */
414 }
415
416 /* Build Decoding table */
417 { U32 u;
418 for (u=0; u<tableSize; u++) {
419 U32 const symbol = tableDecode[u].baseValue;
420 U32 const nextState = symbolNext[symbol]++;
421 tableDecode[u].nbBits = (BYTE) (tableLog - BIT_highbit32(nextState) );
422 tableDecode[u].nextState = (U16) ( (nextState << tableDecode[u].nbBits) - tableSize);
423 assert(nbAdditionalBits[symbol] < 255);
424 tableDecode[u].nbAdditionalBits = (BYTE)nbAdditionalBits[symbol];
425 tableDecode[u].baseValue = baseValue[symbol];
426 } }
427}
MEM_STATIC unsigned BIT_highbit32(U32 val)
Definition: bitstream.h:139
#define assert(x)
Definition: debug.h:53
signed short S16
Definition: mem.h:146
GLdouble s
Definition: gl.h:2039
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble * u
Definition: glfuncs.h:240
#define memcpy(s1, s2, n)
Definition: mkisofs.h:878
unsigned char BYTE
Definition: xxhash.c:193
unsigned int U32
Definition: xxhash.c:195
unsigned short U16
Definition: xxhash.c:194
#define MaxFSELog
#define MaxSeq

Referenced by ZSTD_loadDEntropy().

◆ ZSTD_decompressBlock_internal()

size_t ZSTD_decompressBlock_internal ( ZSTD_DCtx dctx,
void dst,
size_t  dstCapacity,
const void src,
size_t  srcSize,
const int  frame 
)

Definition at line 1341 of file zstd_decompress_block.c.

1344{ /* blockType == blockCompressed */
1345 const BYTE* ip = (const BYTE*)src;
1346 /* isLongOffset must be true if there are long offsets.
1347 * Offsets are long if they are larger than 2^STREAM_ACCUMULATOR_MIN.
1348 * We don't expect that to be the case in 64-bit mode.
1349 * In block mode, window size is not known, so we have to be conservative.
1350 * (note: but it could be evaluated from current-lowLimit)
1351 */
1352 ZSTD_longOffset_e const isLongOffset = (ZSTD_longOffset_e)(MEM_32bits() && (!frame || (dctx->fParams.windowSize > (1ULL << STREAM_ACCUMULATOR_MIN))));
1353 DEBUGLOG(5, "ZSTD_decompressBlock_internal (size : %u)", (U32)srcSize);
1354
1355 RETURN_ERROR_IF(srcSize >= ZSTD_BLOCKSIZE_MAX, srcSize_wrong, "");
1356
1357 /* Decode literals section */
1358 { size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
1359 DEBUGLOG(5, "ZSTD_decodeLiteralsBlock : %u", (U32)litCSize);
1360 if (ZSTD_isError(litCSize)) return litCSize;
1361 ip += litCSize;
1362 srcSize -= litCSize;
1363 }
1364
1365 /* Build Decoding Tables */
1366 {
1367 /* These macros control at build-time which decompressor implementation
1368 * we use. If neither is defined, we do some inspection and dispatch at
1369 * runtime.
1370 */
1371#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
1372 !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
1373 int usePrefetchDecoder = dctx->ddictIsCold;
1374#endif
1375 int nbSeq;
1376 size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, srcSize);
1377 if (ZSTD_isError(seqHSize)) return seqHSize;
1378 ip += seqHSize;
1379 srcSize -= seqHSize;
1380
1381 RETURN_ERROR_IF(dst == NULL && nbSeq > 0, dstSize_tooSmall, "NULL not handled");
1382
1383#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
1384 !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
1385 if ( !usePrefetchDecoder
1386 && (!frame || (dctx->fParams.windowSize > (1<<24)))
1387 && (nbSeq>ADVANCED_SEQS) ) { /* could probably use a larger nbSeq limit */
1388 U32 const shareLongOffsets = ZSTD_getLongOffsetsShare(dctx->OFTptr);
1389 U32 const minShare = MEM_64bits() ? 7 : 20; /* heuristic values, correspond to 2.73% and 7.81% */
1390 usePrefetchDecoder = (shareLongOffsets >= minShare);
1391 }
1392#endif
1393
1394 dctx->ddictIsCold = 0;
1395
1396#if !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT) && \
1397 !defined(ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG)
1398 if (usePrefetchDecoder)
1399#endif
1400#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
1401 return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
1402#endif
1403
1404#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
1405 /* else */
1406 return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
1407#endif
1408 }
1409}
#define STREAM_ACCUMULATOR_MIN
Definition: bitstream.h:47
#define NULL
Definition: types.h:112
#define DEBUGLOG(l,...)
Definition: debug.h:106
MEM_STATIC unsigned MEM_32bits(void)
Definition: mem.h:183
MEM_STATIC unsigned MEM_64bits(void)
Definition: mem.h:184
GLenum src
Definition: glext.h:6340
GLenum GLenum dst
Definition: glext.h:6340
const ZSTD_seqSymbol * OFTptr
ZSTD_frameHeader fParams
Definition: dhcpd.h:62
#define ZSTD_BLOCKSIZE_MAX
Definition: zstd.h:104
static unsigned ZSTD_getLongOffsetsShare(const ZSTD_seqSymbol *offTable)
#define ADVANCED_SEQS
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)
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)
size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx *dctx, int *nbSeqPtr, const void *src, size_t srcSize)
size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx *dctx, const void *src, size_t srcSize)
#define RETURN_ERROR_IF(cond, err,...)
Definition: zstd_internal.h:91
#define ZSTD_isError
Definition: zstd_internal.h:46

Referenced by ZSTD_decompressContinue(), and ZSTD_decompressFrame().