ZBUFF_ as a wrapper to ZSTD streaming API.

This commit is contained in:
Yann Collet 2016-12-06 17:16:41 +01:00
parent a0d4031e7c
commit 9dfd0af164
3 changed files with 72 additions and 417 deletions

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@ -15,17 +15,19 @@
* See 'lib/README.md'.
*****************************************************************/
#ifndef ZSTD_BUFFERED_H_23987
#define ZSTD_BUFFERED_H_23987
#if defined (__cplusplus)
extern "C" {
#endif
#ifndef ZSTD_BUFFERED_H_23987
#define ZSTD_BUFFERED_H_23987
/* *************************************
* Dependencies
***************************************/
#include <stddef.h> /* size_t */
#include <zstd.h> /* ZSTD_CStream, ZSTD_DStream */
/* ***************************************************************
@ -48,7 +50,7 @@ extern "C" {
#ifdef ZBUFF_DISABLE_DEPRECATE_WARNINGS
# define ZBUFF_DEPRECATED(message) /* disable deprecation warnings */
#else
# if (defined(__GNUC__) && (__GNUC__ >= 4)) || defined(__clang__)
# if (defined(__GNUC__) && (__GNUC__ >= 5)) || defined(__clang__)
# define ZBUFF_DEPRECATED(message) __attribute__((deprecated(message)))
# elif defined(__GNUC__) && (__GNUC__ >= 3)
# define ZBUFF_DEPRECATED(message) __attribute__((deprecated))
@ -70,7 +72,7 @@ extern "C" {
* ZBUFF and ZSTD are 100% interoperable,
* frames created by one can be decoded by the other one */
typedef struct ZBUFF_CCtx_s ZBUFF_CCtx;
typedef ZSTD_CStream ZBUFF_CCtx;
ZBUFF_DEPRECATED("use ZSTD_createCStream") ZBUFF_CCtx* ZBUFF_createCCtx(void);
ZBUFF_DEPRECATED("use ZSTD_freeCStream") size_t ZBUFF_freeCCtx(ZBUFF_CCtx* cctx);
@ -122,7 +124,7 @@ ZBUFF_DEPRECATED("use ZSTD_endStream") size_t ZBUFF_compressEnd(ZBUFF_CCtx*
* **************************************************/
typedef struct ZBUFF_DCtx_s ZBUFF_DCtx;
typedef ZSTD_DStream ZBUFF_DCtx;
ZBUFF_DEPRECATED("use ZSTD_createDStream") ZBUFF_DCtx* ZBUFF_createDCtx(void);
ZBUFF_DEPRECATED("use ZSTD_freeDStream") size_t ZBUFF_freeDCtx(ZBUFF_DCtx* dctx);
@ -172,9 +174,14 @@ ZBUFF_DEPRECATED("use ZSTD_CStreamOutSize") size_t ZBUFF_recommendedCOutSize(voi
ZBUFF_DEPRECATED("use ZSTD_DStreamInSize") size_t ZBUFF_recommendedDInSize(void);
ZBUFF_DEPRECATED("use ZSTD_DStreamOutSize") size_t ZBUFF_recommendedDOutSize(void);
#endif /* ZSTD_BUFFERED_H_23987 */
#ifdef ZBUFF_STATIC_LINKING_ONLY
#ifndef ZBUFF_STATIC_H_30298098432
#define ZBUFF_STATIC_H_30298098432
/* ====================================================================================
* The definitions in this section are considered experimental.
* They should never be used in association with a dynamic library, as they may change in the future.
@ -203,11 +210,11 @@ ZBUFF_DEPRECATED("use ZSTD_initDStream_usingDict") size_t ZBUFF_compressInit_adv
ZSTD_parameters params, unsigned long long pledgedSrcSize);
#endif /* ZBUFF_STATIC_LINKING_ONLY */
#endif /* ZBUFF_STATIC_H_30298098432 */
#endif /* ZBUFF_STATIC_LINKING_ONLY */
#if defined (__cplusplus)
}
#endif
#endif /* ZSTD_BUFFERED_H_23987 */

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@ -12,19 +12,10 @@
/* *************************************
* Dependencies
***************************************/
#include <stdlib.h>
#include "error_private.h"
#include "zstd_internal.h" /* MIN, ZSTD_BLOCKHEADERSIZE, defaultCustomMem */
#define ZBUFF_STATIC_LINKING_ONLY
#include "zbuff.h"
/* *************************************
* Constants
***************************************/
static size_t const ZBUFF_endFrameSize = ZSTD_BLOCKHEADERSIZE;
/*-***********************************************************
* Streaming compression
*
@ -58,59 +49,19 @@ static size_t const ZBUFF_endFrameSize = ZSTD_BLOCKHEADERSIZE;
* output : ZSTD_compressBound(ZSTD_BLOCKSIZE_MAX) + ZSTD_blockHeaderSize + ZBUFF_endFrameSize : ensures it's always possible to write/flush/end a full block at best speed.
* ***********************************************************/
typedef enum { ZBUFFcs_init, ZBUFFcs_load, ZBUFFcs_flush, ZBUFFcs_final } ZBUFF_cStage;
/* *** Resources *** */
struct ZBUFF_CCtx_s {
ZSTD_CCtx* zc;
char* inBuff;
size_t inBuffSize;
size_t inToCompress;
size_t inBuffPos;
size_t inBuffTarget;
size_t blockSize;
char* outBuff;
size_t outBuffSize;
size_t outBuffContentSize;
size_t outBuffFlushedSize;
ZBUFF_cStage stage;
U32 checksum;
U32 frameEnded;
ZSTD_customMem customMem;
}; /* typedef'd tp ZBUFF_CCtx within "zbuff.h" */
ZBUFF_CCtx* ZBUFF_createCCtx(void)
{
return ZBUFF_createCCtx_advanced(defaultCustomMem);
return ZSTD_createCStream();
}
ZBUFF_CCtx* ZBUFF_createCCtx_advanced(ZSTD_customMem customMem)
{
ZBUFF_CCtx* zbc;
if (!customMem.customAlloc && !customMem.customFree)
customMem = defaultCustomMem;
if (!customMem.customAlloc || !customMem.customFree)
return NULL;
zbc = (ZBUFF_CCtx*)customMem.customAlloc(customMem.opaque, sizeof(ZBUFF_CCtx));
if (zbc==NULL) return NULL;
memset(zbc, 0, sizeof(ZBUFF_CCtx));
memcpy(&zbc->customMem, &customMem, sizeof(ZSTD_customMem));
zbc->zc = ZSTD_createCCtx_advanced(customMem);
if (zbc->zc == NULL) { ZBUFF_freeCCtx(zbc); return NULL; }
return zbc;
return ZSTD_createCStream_advanced(customMem);
}
size_t ZBUFF_freeCCtx(ZBUFF_CCtx* zbc)
{
if (zbc==NULL) return 0; /* support free on NULL */
ZSTD_freeCCtx(zbc->zc);
if (zbc->inBuff) zbc->customMem.customFree(zbc->customMem.opaque, zbc->inBuff);
if (zbc->outBuff) zbc->customMem.customFree(zbc->customMem.opaque, zbc->outBuff);
zbc->customMem.customFree(zbc->customMem.opaque, zbc);
return 0;
return ZSTD_freeCStream(zbc);
}
@ -120,148 +71,40 @@ size_t ZBUFF_compressInit_advanced(ZBUFF_CCtx* zbc,
const void* dict, size_t dictSize,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
{
/* allocate buffers */
{ size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog;
if (zbc->inBuffSize < neededInBuffSize) {
zbc->inBuffSize = neededInBuffSize;
zbc->customMem.customFree(zbc->customMem.opaque, zbc->inBuff); /* should not be necessary */
zbc->inBuff = (char*)zbc->customMem.customAlloc(zbc->customMem.opaque, neededInBuffSize);
if (zbc->inBuff == NULL) return ERROR(memory_allocation);
}
zbc->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize);
}
if (zbc->outBuffSize < ZSTD_compressBound(zbc->blockSize)+1) {
zbc->outBuffSize = ZSTD_compressBound(zbc->blockSize)+1;
zbc->customMem.customFree(zbc->customMem.opaque, zbc->outBuff); /* should not be necessary */
zbc->outBuff = (char*)zbc->customMem.customAlloc(zbc->customMem.opaque, zbc->outBuffSize);
if (zbc->outBuff == NULL) return ERROR(memory_allocation);
}
{ size_t const errorCode = ZSTD_compressBegin_advanced(zbc->zc, dict, dictSize, params, pledgedSrcSize);
if (ZSTD_isError(errorCode)) return errorCode; }
zbc->inToCompress = 0;
zbc->inBuffPos = 0;
zbc->inBuffTarget = zbc->blockSize;
zbc->outBuffContentSize = zbc->outBuffFlushedSize = 0;
zbc->stage = ZBUFFcs_load;
zbc->checksum = params.fParams.checksumFlag > 0;
zbc->frameEnded = 0;
return 0; /* ready to go */
return ZSTD_initCStream_advanced(zbc, dict, dictSize, params, pledgedSrcSize);
}
size_t ZBUFF_compressInitDictionary(ZBUFF_CCtx* zbc, const void* dict, size_t dictSize, int compressionLevel)
{
ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
return ZBUFF_compressInit_advanced(zbc, dict, dictSize, params, 0);
return ZSTD_initCStream_usingDict(zbc, dict, dictSize, compressionLevel);
}
size_t ZBUFF_compressInit(ZBUFF_CCtx* zbc, int compressionLevel)
{
return ZBUFF_compressInitDictionary(zbc, NULL, 0, compressionLevel);
return ZSTD_initCStream(zbc, compressionLevel);
}
/* internal util function */
MEM_STATIC size_t ZBUFF_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
size_t const length = MIN(dstCapacity, srcSize);
memcpy(dst, src, length);
return length;
}
/* ====== Compression ====== */
typedef enum { zbf_gather, zbf_flush, zbf_end } ZBUFF_flush_e;
static size_t ZBUFF_compressContinue_generic(ZBUFF_CCtx* zbc,
void* dst, size_t* dstCapacityPtr,
const void* src, size_t* srcSizePtr,
ZBUFF_flush_e const flush)
{
U32 someMoreWork = 1;
const char* const istart = (const char*)src;
const char* const iend = istart + *srcSizePtr;
const char* ip = istart;
char* const ostart = (char*)dst;
char* const oend = ostart + *dstCapacityPtr;
char* op = ostart;
while (someMoreWork) {
switch(zbc->stage)
{
case ZBUFFcs_init: return ERROR(init_missing); /* call ZBUFF_compressInit() first ! */
case ZBUFFcs_load:
/* complete inBuffer */
{ size_t const toLoad = zbc->inBuffTarget - zbc->inBuffPos;
size_t const loaded = ZBUFF_limitCopy(zbc->inBuff + zbc->inBuffPos, toLoad, ip, iend-ip);
zbc->inBuffPos += loaded;
ip += loaded;
if ( (zbc->inBuffPos==zbc->inToCompress) || (!flush && (toLoad != loaded)) ) {
someMoreWork = 0; break; /* not enough input to get a full block : stop there, wait for more */
} }
/* compress current block (note : this stage cannot be stopped in the middle) */
{ void* cDst;
size_t cSize;
size_t const iSize = zbc->inBuffPos - zbc->inToCompress;
size_t oSize = oend-op;
if (oSize >= ZSTD_compressBound(iSize))
cDst = op; /* compress directly into output buffer (avoid flush stage) */
else
cDst = zbc->outBuff, oSize = zbc->outBuffSize;
cSize = (flush == zbf_end) ?
ZSTD_compressEnd(zbc->zc, cDst, oSize, zbc->inBuff + zbc->inToCompress, iSize) :
ZSTD_compressContinue(zbc->zc, cDst, oSize, zbc->inBuff + zbc->inToCompress, iSize);
if (ZSTD_isError(cSize)) return cSize;
if (flush == zbf_end) zbc->frameEnded = 1;
/* prepare next block */
zbc->inBuffTarget = zbc->inBuffPos + zbc->blockSize;
if (zbc->inBuffTarget > zbc->inBuffSize)
zbc->inBuffPos = 0, zbc->inBuffTarget = zbc->blockSize; /* note : inBuffSize >= blockSize */
zbc->inToCompress = zbc->inBuffPos;
if (cDst == op) { op += cSize; break; } /* no need to flush */
zbc->outBuffContentSize = cSize;
zbc->outBuffFlushedSize = 0;
zbc->stage = ZBUFFcs_flush; /* continue to flush stage */
}
case ZBUFFcs_flush:
{ size_t const toFlush = zbc->outBuffContentSize - zbc->outBuffFlushedSize;
size_t const flushed = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outBuffFlushedSize, toFlush);
op += flushed;
zbc->outBuffFlushedSize += flushed;
if (toFlush!=flushed) { someMoreWork = 0; break; } /* dst too small to store flushed data : stop there */
zbc->outBuffContentSize = zbc->outBuffFlushedSize = 0;
zbc->stage = ZBUFFcs_load;
break;
}
case ZBUFFcs_final:
someMoreWork = 0; /* do nothing */
break;
default:
return ERROR(GENERIC); /* impossible */
}
}
*srcSizePtr = ip - istart;
*dstCapacityPtr = op - ostart;
if (zbc->frameEnded) return 0;
{ size_t hintInSize = zbc->inBuffTarget - zbc->inBuffPos;
if (hintInSize==0) hintInSize = zbc->blockSize;
return hintInSize;
}
}
size_t ZBUFF_compressContinue(ZBUFF_CCtx* zbc,
void* dst, size_t* dstCapacityPtr,
const void* src, size_t* srcSizePtr)
{
return ZBUFF_compressContinue_generic(zbc, dst, dstCapacityPtr, src, srcSizePtr, zbf_gather);
size_t result;
ZSTD_outBuffer outBuff;
ZSTD_inBuffer inBuff;
outBuff.dst = dst;
outBuff.pos = 0;
outBuff.size = *dstCapacityPtr;
inBuff.src = src;
inBuff.pos = 0;
inBuff.size = *srcSizePtr;
result = ZSTD_compressStream(zbc, &outBuff, &inBuff);
*dstCapacityPtr = outBuff.pos;
*srcSizePtr = inBuff.pos;
return result;
}
@ -270,44 +113,27 @@ size_t ZBUFF_compressContinue(ZBUFF_CCtx* zbc,
size_t ZBUFF_compressFlush(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr)
{
size_t srcSize = 0;
ZBUFF_compressContinue_generic(zbc, dst, dstCapacityPtr, &srcSize, &srcSize, zbf_flush); /* use a valid src address instead of NULL */
return zbc->outBuffContentSize - zbc->outBuffFlushedSize;
size_t result;
ZSTD_outBuffer outBuff;
outBuff.dst = dst;
outBuff.pos = 0;
outBuff.size = *dstCapacityPtr;
result = ZSTD_flushStream(zbc, &outBuff);
*dstCapacityPtr = outBuff.pos;
return result;
}
size_t ZBUFF_compressEnd(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr)
{
BYTE* const ostart = (BYTE*)dst;
BYTE* const oend = ostart + *dstCapacityPtr;
BYTE* op = ostart;
if (zbc->stage != ZBUFFcs_final) {
/* flush whatever remains */
size_t outSize = *dstCapacityPtr;
size_t srcSize = 0;
size_t const notEnded = ZBUFF_compressContinue_generic(zbc, dst, &outSize, &srcSize, &srcSize, zbf_end); /* use a valid address instead of NULL */
size_t const remainingToFlush = zbc->outBuffContentSize - zbc->outBuffFlushedSize;
op += outSize;
if (remainingToFlush) {
*dstCapacityPtr = op-ostart;
return remainingToFlush + ZBUFF_endFrameSize + (zbc->checksum * 4);
}
/* create epilogue */
zbc->stage = ZBUFFcs_final;
zbc->outBuffContentSize = !notEnded ? 0 :
ZSTD_compressEnd(zbc->zc, zbc->outBuff, zbc->outBuffSize, NULL, 0); /* write epilogue into outBuff */
}
/* flush epilogue */
{ size_t const toFlush = zbc->outBuffContentSize - zbc->outBuffFlushedSize;
size_t const flushed = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outBuffFlushedSize, toFlush);
op += flushed;
zbc->outBuffFlushedSize += flushed;
*dstCapacityPtr = op-ostart;
if (toFlush==flushed) zbc->stage = ZBUFFcs_init; /* end reached */
return toFlush - flushed;
}
size_t result;
ZSTD_outBuffer outBuff;
outBuff.dst = dst;
outBuff.pos = 0;
outBuff.size = *dstCapacityPtr;
result = ZSTD_endStream(zbc, &outBuff);
*dstCapacityPtr = outBuff.pos;
return result;
}
@ -315,5 +141,5 @@ size_t ZBUFF_compressEnd(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr)
/* *************************************
* Tool functions
***************************************/
size_t ZBUFF_recommendedCInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
size_t ZBUFF_recommendedCOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + ZBUFF_endFrameSize; }
size_t ZBUFF_recommendedCInSize(void) { return ZSTD_CStreamInSize(); }
size_t ZBUFF_recommendedCOutSize(void) { return ZSTD_CStreamOutSize(); }

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@ -12,68 +12,23 @@
/* *************************************
* Dependencies
***************************************/
#include <stdlib.h>
#include "error_private.h"
#include "zstd_internal.h" /* MIN, ZSTD_blockHeaderSize, ZSTD_BLOCKSIZE_MAX */
#define ZBUFF_STATIC_LINKING_ONLY
#include "zbuff.h"
typedef enum { ZBUFFds_init, ZBUFFds_loadHeader,
ZBUFFds_read, ZBUFFds_load, ZBUFFds_flush } ZBUFF_dStage;
/* *** Resource management *** */
struct ZBUFF_DCtx_s {
ZSTD_DCtx* zd;
ZSTD_frameParams fParams;
ZBUFF_dStage stage;
char* inBuff;
size_t inBuffSize;
size_t inPos;
char* outBuff;
size_t outBuffSize;
size_t outStart;
size_t outEnd;
size_t blockSize;
BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
size_t lhSize;
ZSTD_customMem customMem;
}; /* typedef'd to ZBUFF_DCtx within "zbuff.h" */
ZBUFF_DCtx* ZBUFF_createDCtx(void)
{
return ZBUFF_createDCtx_advanced(defaultCustomMem);
return ZSTD_createDStream();
}
ZBUFF_DCtx* ZBUFF_createDCtx_advanced(ZSTD_customMem customMem)
{
ZBUFF_DCtx* zbd;
if (!customMem.customAlloc && !customMem.customFree)
customMem = defaultCustomMem;
if (!customMem.customAlloc || !customMem.customFree)
return NULL;
zbd = (ZBUFF_DCtx*)customMem.customAlloc(customMem.opaque, sizeof(ZBUFF_DCtx));
if (zbd==NULL) return NULL;
memset(zbd, 0, sizeof(ZBUFF_DCtx));
memcpy(&zbd->customMem, &customMem, sizeof(ZSTD_customMem));
zbd->zd = ZSTD_createDCtx_advanced(customMem);
if (zbd->zd == NULL) { ZBUFF_freeDCtx(zbd); return NULL; }
zbd->stage = ZBUFFds_init;
return zbd;
return ZSTD_createDStream_advanced(customMem);
}
size_t ZBUFF_freeDCtx(ZBUFF_DCtx* zbd)
{
if (zbd==NULL) return 0; /* support free on null */
ZSTD_freeDCtx(zbd->zd);
if (zbd->inBuff) zbd->customMem.customFree(zbd->customMem.opaque, zbd->inBuff);
if (zbd->outBuff) zbd->customMem.customFree(zbd->customMem.opaque, zbd->outBuff);
zbd->customMem.customFree(zbd->customMem.opaque, zbd);
return 0;
return ZSTD_freeDStream(zbd);
}
@ -81,23 +36,12 @@ size_t ZBUFF_freeDCtx(ZBUFF_DCtx* zbd)
size_t ZBUFF_decompressInitDictionary(ZBUFF_DCtx* zbd, const void* dict, size_t dictSize)
{
zbd->stage = ZBUFFds_loadHeader;
zbd->lhSize = zbd->inPos = zbd->outStart = zbd->outEnd = 0;
return ZSTD_decompressBegin_usingDict(zbd->zd, dict, dictSize);
return ZSTD_initDStream_usingDict(zbd, dict, dictSize);
}
size_t ZBUFF_decompressInit(ZBUFF_DCtx* zbd)
{
return ZBUFF_decompressInitDictionary(zbd, NULL, 0);
}
/* internal util function */
MEM_STATIC size_t ZBUFF_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
size_t const length = MIN(dstCapacity, srcSize);
memcpy(dst, src, length);
return length;
return ZSTD_initDStream(zbd);
}
@ -107,146 +51,24 @@ size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbd,
void* dst, size_t* dstCapacityPtr,
const void* src, size_t* srcSizePtr)
{
const char* const istart = (const char*)src;
const char* const iend = istart + *srcSizePtr;
const char* ip = istart;
char* const ostart = (char*)dst;
char* const oend = ostart + *dstCapacityPtr;
char* op = ostart;
U32 someMoreWork = 1;
while (someMoreWork) {
switch(zbd->stage)
{
case ZBUFFds_init :
return ERROR(init_missing);
case ZBUFFds_loadHeader :
{ size_t const hSize = ZSTD_getFrameParams(&(zbd->fParams), zbd->headerBuffer, zbd->lhSize);
if (ZSTD_isError(hSize)) return hSize;
if (hSize != 0) { /* need more input */
size_t const toLoad = hSize - zbd->lhSize; /* if hSize!=0, hSize > zbd->lhSize */
if (toLoad > (size_t)(iend-ip)) { /* not enough input to load full header */
memcpy(zbd->headerBuffer + zbd->lhSize, ip, iend-ip);
zbd->lhSize += iend-ip;
*dstCapacityPtr = 0;
return (hSize - zbd->lhSize) + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */
}
memcpy(zbd->headerBuffer + zbd->lhSize, ip, toLoad); zbd->lhSize = hSize; ip += toLoad;
break;
} }
/* Consume header */
{ size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zbd->zd); /* == ZSTD_frameHeaderSize_min */
size_t const h1Result = ZSTD_decompressContinue(zbd->zd, NULL, 0, zbd->headerBuffer, h1Size);
if (ZSTD_isError(h1Result)) return h1Result; /* should not happen : already checked */
if (h1Size < zbd->lhSize) { /* long header */
size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zbd->zd);
size_t const h2Result = ZSTD_decompressContinue(zbd->zd, NULL, 0, zbd->headerBuffer+h1Size, h2Size);
if (ZSTD_isError(h2Result)) return h2Result;
} }
zbd->fParams.windowSize = MAX(zbd->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
/* Frame header instruct buffer sizes */
{ size_t const blockSize = MIN(zbd->fParams.windowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
size_t const neededOutSize = zbd->fParams.windowSize + blockSize;
zbd->blockSize = blockSize;
if (zbd->inBuffSize < blockSize) {
zbd->customMem.customFree(zbd->customMem.opaque, zbd->inBuff);
zbd->inBuffSize = blockSize;
zbd->inBuff = (char*)zbd->customMem.customAlloc(zbd->customMem.opaque, blockSize);
if (zbd->inBuff == NULL) return ERROR(memory_allocation);
}
if (zbd->outBuffSize < neededOutSize) {
zbd->customMem.customFree(zbd->customMem.opaque, zbd->outBuff);
zbd->outBuffSize = neededOutSize;
zbd->outBuff = (char*)zbd->customMem.customAlloc(zbd->customMem.opaque, neededOutSize);
if (zbd->outBuff == NULL) return ERROR(memory_allocation);
} }
zbd->stage = ZBUFFds_read;
/* pass-through */
case ZBUFFds_read:
{ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zbd->zd);
if (neededInSize==0) { /* end of frame */
zbd->stage = ZBUFFds_init;
someMoreWork = 0;
break;
}
if ((size_t)(iend-ip) >= neededInSize) { /* decode directly from src */
const int isSkipFrame = ZSTD_isSkipFrame(zbd->zd);
size_t const decodedSize = ZSTD_decompressContinue(zbd->zd,
zbd->outBuff + zbd->outStart, (isSkipFrame ? 0 : zbd->outBuffSize - zbd->outStart),
ip, neededInSize);
if (ZSTD_isError(decodedSize)) return decodedSize;
ip += neededInSize;
if (!decodedSize && !isSkipFrame) break; /* this was just a header */
zbd->outEnd = zbd->outStart + decodedSize;
zbd->stage = ZBUFFds_flush;
break;
}
if (ip==iend) { someMoreWork = 0; break; } /* no more input */
zbd->stage = ZBUFFds_load;
/* pass-through */
}
case ZBUFFds_load:
{ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zbd->zd);
size_t const toLoad = neededInSize - zbd->inPos; /* should always be <= remaining space within inBuff */
size_t loadedSize;
if (toLoad > zbd->inBuffSize - zbd->inPos) return ERROR(corruption_detected); /* should never happen */
loadedSize = ZBUFF_limitCopy(zbd->inBuff + zbd->inPos, toLoad, ip, iend-ip);
ip += loadedSize;
zbd->inPos += loadedSize;
if (loadedSize < toLoad) { someMoreWork = 0; break; } /* not enough input, wait for more */
/* decode loaded input */
{ const int isSkipFrame = ZSTD_isSkipFrame(zbd->zd);
size_t const decodedSize = ZSTD_decompressContinue(zbd->zd,
zbd->outBuff + zbd->outStart, zbd->outBuffSize - zbd->outStart,
zbd->inBuff, neededInSize);
if (ZSTD_isError(decodedSize)) return decodedSize;
zbd->inPos = 0; /* input is consumed */
if (!decodedSize && !isSkipFrame) { zbd->stage = ZBUFFds_read; break; } /* this was just a header */
zbd->outEnd = zbd->outStart + decodedSize;
zbd->stage = ZBUFFds_flush;
/* pass-through */
} }
case ZBUFFds_flush:
{ size_t const toFlushSize = zbd->outEnd - zbd->outStart;
size_t const flushedSize = ZBUFF_limitCopy(op, oend-op, zbd->outBuff + zbd->outStart, toFlushSize);
op += flushedSize;
zbd->outStart += flushedSize;
if (flushedSize == toFlushSize) { /* flush completed */
zbd->stage = ZBUFFds_read;
if (zbd->outStart + zbd->blockSize > zbd->outBuffSize)
zbd->outStart = zbd->outEnd = 0;
break;
}
/* cannot flush everything */
someMoreWork = 0;
break;
}
default: return ERROR(GENERIC); /* impossible */
} }
/* result */
*srcSizePtr = ip-istart;
*dstCapacityPtr = op-ostart;
{ size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zbd->zd);
if (!nextSrcSizeHint) return (zbd->outEnd != zbd->outStart); /* return 0 only if fully flushed too */
nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zbd->zd) == ZSTDnit_block);
if (zbd->inPos > nextSrcSizeHint) return ERROR(GENERIC); /* should never happen */
nextSrcSizeHint -= zbd->inPos; /* already loaded*/
return nextSrcSizeHint;
}
ZSTD_outBuffer outBuff;
ZSTD_inBuffer inBuff;
size_t result;
outBuff.dst = dst;
outBuff.pos = 0;
outBuff.size = *dstCapacityPtr;
inBuff.src = src;
inBuff.pos = 0;
inBuff.size = *srcSizePtr;
result = ZSTD_decompressStream(zbd, &outBuff, &inBuff);
*dstCapacityPtr = outBuff.pos;
*srcSizePtr = inBuff.pos;
return result;
}
/* *************************************
* Tool functions
***************************************/
size_t ZBUFF_recommendedDInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize /* block header size*/ ; }
size_t ZBUFF_recommendedDOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
size_t ZBUFF_recommendedDInSize(void) { return ZSTD_DStreamInSize(); }
size_t ZBUFF_recommendedDOutSize(void) { return ZSTD_DStreamOutSize(); }