size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbc, void* dst, size_t* maxDstSizePtr, const void* src, size_t* srcSizePtr)
{
const char* const istart = (const char*)src;
const char* ip = istart;
const char* const iend = istart + *srcSizePtr;
char* const ostart = (char*)dst;
char* op = ostart;
char* const oend = ostart + *maxDstSizePtr;
U32 notDone = 1;
while (notDone)
{
switch(zbc->stage)
{
case ZBUFFds_init :
return ERROR(init_missing);
case ZBUFFds_readHeader :
/* read header from src */
{
size_t headerSize = ZSTD_getFrameParams(&(zbc->params), src, *srcSizePtr);
if (ZSTD_isError(headerSize)) return headerSize;
if (headerSize)
{
/* not enough input to decode header : tell how many bytes would be necessary */
memcpy(zbc->headerBuffer+zbc->hPos, src, *srcSizePtr);
zbc->hPos += *srcSizePtr;
*maxDstSizePtr = 0;
zbc->stage = ZBUFFds_loadHeader;
return headerSize - zbc->hPos;
}
zbc->stage = ZBUFFds_decodeHeader;
break;
}
case ZBUFFds_loadHeader:
/* complete header from src */
{
size_t headerSize = ZBUFF_limitCopy(
zbc->headerBuffer + zbc->hPos, ZSTD_frameHeaderSize_max - zbc->hPos,
src, *srcSizePtr);
zbc->hPos += headerSize;
ip += headerSize;
headerSize = ZSTD_getFrameParams(&(zbc->params), zbc->headerBuffer, zbc->hPos);
if (ZSTD_isError(headerSize)) return headerSize;
if (headerSize)
{
/* not enough input to decode header : tell how many bytes would be necessary */
*maxDstSizePtr = 0;
return headerSize - zbc->hPos;
}
// zbc->stage = ZBUFFds_decodeHeader; break; /* useless : stage follows */
}
case ZBUFFds_decodeHeader:
/* apply header to create / resize buffers */
{
size_t neededOutSize = (size_t)1 << zbc->params.windowLog;
size_t neededInSize = BLOCKSIZE; /* a block is never > BLOCKSIZE */
if (zbc->inBuffSize < neededInSize)
{
free(zbc->inBuff);
zbc->inBuffSize = neededInSize;
zbc->inBuff = (char*)malloc(neededInSize);
if (zbc->inBuff == NULL) return ERROR(memory_allocation);
}
if (zbc->outBuffSize < neededOutSize)
{
free(zbc->outBuff);
zbc->outBuffSize = neededOutSize;
zbc->outBuff = (char*)malloc(neededOutSize);
if (zbc->outBuff == NULL) return ERROR(memory_allocation);
}
}
if (zbc->dictSize)
ZSTD_decompress_insertDictionary(zbc->zc, zbc->dict, zbc->dictSize);
if (zbc->hPos)
{
/* some data already loaded into headerBuffer : transfer into inBuff */
memcpy(zbc->inBuff, zbc->headerBuffer, zbc->hPos);
zbc->inPos = zbc->hPos;
zbc->hPos = 0;
zbc->stage = ZBUFFds_load;
break;
}
zbc->stage = ZBUFFds_read;
case ZBUFFds_read:
{
size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
if (neededInSize==0) /* end of frame */
{
zbc->stage = ZBUFFds_init;
notDone = 0;
break;
}
if ((size_t)(iend-ip) >= neededInSize)
{
/* directly decode from src */
size_t decodedSize = ZSTD_decompressContinue(zbc->zc,
zbc->outBuff + zbc->outStart, zbc->outBuffSize - zbc->outStart,
ip, neededInSize);
if (ZSTD_isError(decodedSize)) return decodedSize;
ip += neededInSize;
if (!decodedSize) break; /* this was just a header */
zbc->outEnd = zbc->outStart + decodedSize;
zbc->stage = ZBUFFds_flush;
break;
}
if (ip==iend) { notDone = 0; break; } /* no more input */
zbc->stage = ZBUFFds_load;
}
case ZBUFFds_load:
{
size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
size_t toLoad = neededInSize - zbc->inPos; /* should always be <= remaining space within inBuff */
size_t loadedSize;
if (toLoad > zbc->inBuffSize - zbc->inPos) return ERROR(corruption_detected); /* should never happen */
loadedSize = ZBUFF_limitCopy(zbc->inBuff + zbc->inPos, toLoad, ip, iend-ip);
ip += loadedSize;
zbc->inPos += loadedSize;
if (loadedSize < toLoad) { notDone = 0; break; } /* not enough input, wait for more */
{
size_t decodedSize = ZSTD_decompressContinue(zbc->zc,
zbc->outBuff + zbc->outStart, zbc->outBuffSize - zbc->outStart,
zbc->inBuff, neededInSize);
if (ZSTD_isError(decodedSize)) return decodedSize;
zbc->inPos = 0; /* input is consumed */
if (!decodedSize) { zbc->stage = ZBUFFds_read; break; } /* this was just a header */
zbc->outEnd = zbc->outStart + decodedSize;
zbc->stage = ZBUFFds_flush;
// break; /* ZBUFFds_flush follows */
}
}
case ZBUFFds_flush:
{
size_t toFlushSize = zbc->outEnd - zbc->outStart;
size_t flushedSize = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outStart, toFlushSize);
op += flushedSize;
zbc->outStart += flushedSize;
if (flushedSize == toFlushSize)
{
zbc->stage = ZBUFFds_read;
if (zbc->outStart + BLOCKSIZE > zbc->outBuffSize)
zbc->outStart = zbc->outEnd = 0;
break;
}
/* cannot flush everything */
notDone = 0;
break;
}
}
}
*srcSizePtr = ip-istart;
*maxDstSizePtr = op-ostart;
{
size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zbc->zc);
if (nextSrcSizeHint > 3) nextSrcSizeHint+= 3; /* get the next block header while at it */
nextSrcSizeHint -= zbc->inPos; /* already loaded*/
return nextSrcSizeHint;
}
}
int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compressibility)
{
BYTE* cNoiseBuffer[5];
BYTE* srcBuffer;
BYTE* cBuffer;
BYTE* dstBuffer;
BYTE* mirrorBuffer;
size_t srcBufferSize = (size_t)1<<maxSrcLog;
size_t dstBufferSize = (size_t)1<<maxSampleLog;
size_t cBufferSize = ZSTD_compressBound(dstBufferSize);
U32 result = 0;
U32 testNb = 0;
U32 coreSeed = seed, lseed = 0;
ZSTD_CCtx* refCtx;
ZSTD_CCtx* ctx;
ZSTD_DCtx* dctx;
U32 startTime = FUZ_GetMilliStart();
/* allocation */
refCtx = ZSTD_createCCtx();
ctx = ZSTD_createCCtx();
dctx= ZSTD_createDCtx();
cNoiseBuffer[0] = (BYTE*)malloc (srcBufferSize);
cNoiseBuffer[1] = (BYTE*)malloc (srcBufferSize);
cNoiseBuffer[2] = (BYTE*)malloc (srcBufferSize);
cNoiseBuffer[3] = (BYTE*)malloc (srcBufferSize);
cNoiseBuffer[4] = (BYTE*)malloc (srcBufferSize);
dstBuffer = (BYTE*)malloc (dstBufferSize);
mirrorBuffer = (BYTE*)malloc (dstBufferSize);
cBuffer = (BYTE*)malloc (cBufferSize);
CHECK (!cNoiseBuffer[0] || !cNoiseBuffer[1] || !cNoiseBuffer[2] || !cNoiseBuffer[3] || !cNoiseBuffer[4]
|| !dstBuffer || !mirrorBuffer || !cBuffer || !refCtx || !ctx || !dctx,
"Not enough memory, fuzzer tests cancelled");
/* Create initial samples */
RDG_genBuffer(cNoiseBuffer[0], srcBufferSize, 0.00, 0., coreSeed); /* pure noise */
RDG_genBuffer(cNoiseBuffer[1], srcBufferSize, 0.05, 0., coreSeed); /* barely compressible */
RDG_genBuffer(cNoiseBuffer[2], srcBufferSize, compressibility, 0., coreSeed);
RDG_genBuffer(cNoiseBuffer[3], srcBufferSize, 0.95, 0., coreSeed); /* highly compressible */
RDG_genBuffer(cNoiseBuffer[4], srcBufferSize, 1.00, 0., coreSeed); /* sparse content */
srcBuffer = cNoiseBuffer[2];
/* catch up testNb */
for (testNb=1; testNb < startTest; testNb++)
FUZ_rand(&coreSeed);
/* test loop */
for ( ; (testNb <= nbTests) || (FUZ_GetMilliSpan(startTime) < g_testTime); testNb++ )
{
size_t sampleSize, sampleStart, maxTestSize, totalTestSize;
size_t cSize, dSize, dSupSize, errorCode, totalCSize, totalGenSize;
U32 sampleSizeLog, buffNb, cLevelMod, nbChunks, n;
XXH64_CREATESTATE_STATIC(xxh64);
U64 crcOrig, crcDest;
int cLevel;
BYTE* sampleBuffer;
const BYTE* dict;
size_t dictSize;
/* init */
if (nbTests >= testNb)
{ DISPLAYUPDATE(2, "\r%6u/%6u ", testNb, nbTests); }
else { DISPLAYUPDATE(2, "\r%6u ", testNb); }
FUZ_rand(&coreSeed);
lseed = coreSeed ^ prime1;
buffNb = FUZ_rand(&lseed) & 127;
if (buffNb & 7) buffNb=2;
else
{
buffNb >>= 3;
if (buffNb & 7)
{
const U32 tnb[2] = { 1, 3 };
buffNb = tnb[buffNb >> 3];
}
else
{
const U32 tnb[2] = { 0, 4 };
buffNb = tnb[buffNb >> 3];
}
}
srcBuffer = cNoiseBuffer[buffNb];
sampleSizeLog = FUZ_rand(&lseed) % maxSampleLog;
sampleSize = (size_t)1 << sampleSizeLog;
sampleSize += FUZ_rand(&lseed) & (sampleSize-1);
sampleStart = FUZ_rand(&lseed) % (srcBufferSize - sampleSize);
/* create sample buffer (to catch read error with valgrind & sanitizers) */
sampleBuffer = (BYTE*)malloc(sampleSize);
CHECK (sampleBuffer==NULL, "not enough memory for sample buffer");
memcpy(sampleBuffer, srcBuffer + sampleStart, sampleSize);
crcOrig = XXH64(sampleBuffer, sampleSize, 0);
/* compression test */
cLevelMod = MAX(1, 38 - (int)(MAX(9, sampleSizeLog) * 2)); /* use high compression levels with small samples, for speed */
cLevel = (FUZ_rand(&lseed) % cLevelMod) +1;
cSize = ZSTD_compressCCtx(ctx, cBuffer, cBufferSize, sampleBuffer, sampleSize, cLevel);
CHECK(ZSTD_isError(cSize), "ZSTD_compressCCtx failed");
/* compression failure test : too small dest buffer */
if (cSize > 3)
{
const size_t missing = (FUZ_rand(&lseed) % (cSize-2)) + 1; /* no problem, as cSize > 4 (frameHeaderSizer) */
const size_t tooSmallSize = cSize - missing;
static const U32 endMark = 0x4DC2B1A9;
U32 endCheck;
memcpy(dstBuffer+tooSmallSize, &endMark, 4);
errorCode = ZSTD_compressCCtx(ctx, dstBuffer, tooSmallSize, sampleBuffer, sampleSize, cLevel);
CHECK(!ZSTD_isError(errorCode), "ZSTD_compressCCtx should have failed ! (buffer too small : %u < %u)", (U32)tooSmallSize, (U32)cSize);
memcpy(&endCheck, dstBuffer+tooSmallSize, 4);
CHECK(endCheck != endMark, "ZSTD_compressCCtx : dst buffer overflow");
}
/* successfull decompression tests*/
dSupSize = (FUZ_rand(&lseed) & 1) ? 0 : (FUZ_rand(&lseed) & 31) + 1;
dSize = ZSTD_decompress(dstBuffer, sampleSize + dSupSize, cBuffer, cSize);
CHECK(dSize != sampleSize, "ZSTD_decompress failed (%s) (srcSize : %u ; cSize : %u)", ZSTD_getErrorName(dSize), (U32)sampleSize, (U32)cSize);
crcDest = XXH64(dstBuffer, sampleSize, 0);
CHECK(crcOrig != crcDest, "decompression result corrupted (pos %u / %u)", (U32)findDiff(sampleBuffer, dstBuffer, sampleSize), (U32)sampleSize);
free(sampleBuffer); /* no longer useful after this point */
/* truncated src decompression test */
{
const size_t missing = (FUZ_rand(&lseed) % (cSize-2)) + 1; /* no problem, as cSize > 4 (frameHeaderSizer) */
const size_t tooSmallSize = cSize - missing;
void* cBufferTooSmall = malloc(tooSmallSize); /* valgrind will catch overflows */
CHECK(cBufferTooSmall == NULL, "not enough memory !");
memcpy(cBufferTooSmall, cBuffer, tooSmallSize);
errorCode = ZSTD_decompress(dstBuffer, dstBufferSize, cBufferTooSmall, tooSmallSize);
CHECK(!ZSTD_isError(errorCode), "ZSTD_decompress should have failed ! (truncated src buffer)");
free(cBufferTooSmall);
}
/* too small dst decompression test */
if (sampleSize > 3)
{
const size_t missing = (FUZ_rand(&lseed) % (sampleSize-2)) + 1; /* no problem, as cSize > 4 (frameHeaderSizer) */
const size_t tooSmallSize = sampleSize - missing;
static const BYTE token = 0xA9;
dstBuffer[tooSmallSize] = token;
errorCode = ZSTD_decompress(dstBuffer, tooSmallSize, cBuffer, cSize);
CHECK(!ZSTD_isError(errorCode), "ZSTD_decompress should have failed : %u > %u (dst buffer too small)", (U32)errorCode, (U32)tooSmallSize);
CHECK(dstBuffer[tooSmallSize] != token, "ZSTD_decompress : dst buffer overflow");
}
/* noisy src decompression test */
if (cSize > 6)
{
const U32 maxNbBits = FUZ_highbit32((U32)(cSize-4));
size_t pos = 4; /* preserve magic number (too easy to detect) */
U32 nbBits = FUZ_rand(&lseed) % maxNbBits;
size_t mask = (1<<nbBits) - 1;
size_t skipLength = FUZ_rand(&lseed) & mask;
pos += skipLength;
while (pos < cSize)
{
/* add noise */
size_t noiseStart, noiseLength;
nbBits = FUZ_rand(&lseed) % maxNbBits;
if (nbBits>0) nbBits--;
mask = (1<<nbBits) - 1;
noiseLength = (FUZ_rand(&lseed) & mask) + 1;
if ( pos+noiseLength > cSize ) noiseLength = cSize-pos;
noiseStart = FUZ_rand(&lseed) % (srcBufferSize - noiseLength);
memcpy(cBuffer + pos, srcBuffer + noiseStart, noiseLength);
pos += noiseLength;
/* keep some original src */
nbBits = FUZ_rand(&lseed) % maxNbBits;
mask = (1<<nbBits) - 1;
skipLength = FUZ_rand(&lseed) & mask;
pos += skipLength;
}
/* decompress noisy source */
{
U32 noiseSrc = FUZ_rand(&lseed) % 5;
const U32 endMark = 0xA9B1C3D6;
U32 endCheck;
srcBuffer = cNoiseBuffer[noiseSrc];
memcpy(dstBuffer+sampleSize, &endMark, 4);
errorCode = ZSTD_decompress(dstBuffer, sampleSize, cBuffer, cSize);
/* result *may* be an unlikely success, but even then, it must strictly respect dest buffer boundaries */
CHECK((!ZSTD_isError(errorCode)) && (errorCode>sampleSize),
"ZSTD_decompress on noisy src : result is too large : %u > %u (dst buffer)", (U32)errorCode, (U32)sampleSize);
memcpy(&endCheck, dstBuffer+sampleSize, 4);
CHECK(endMark!=endCheck, "ZSTD_decompress on noisy src : dst buffer overflow");
}
}
/* Streaming compression of scattered segments test */
XXH64_reset(xxh64, 0);
nbChunks = (FUZ_rand(&lseed) & 127) + 2;
sampleSizeLog = FUZ_rand(&lseed) % maxSrcLog;
maxTestSize = (size_t)1 << sampleSizeLog;
maxTestSize += FUZ_rand(&lseed) & (maxTestSize-1);
if (maxTestSize >= dstBufferSize) maxTestSize = dstBufferSize-1;
sampleSizeLog = FUZ_rand(&lseed) % maxSampleLog;
sampleSize = (size_t)1 << sampleSizeLog;
sampleSize += FUZ_rand(&lseed) & (sampleSize-1);
sampleStart = FUZ_rand(&lseed) % (srcBufferSize - sampleSize);
dict = srcBuffer + sampleStart;
dictSize = sampleSize;
errorCode = ZSTD_compressBegin(refCtx, (FUZ_rand(&lseed) % (20 - (sampleSizeLog/3))) + 1);
CHECK (ZSTD_isError(errorCode), "start streaming error : %s", ZSTD_getErrorName(errorCode));
errorCode = ZSTD_compress_insertDictionary(refCtx, dict, dictSize);
CHECK (ZSTD_isError(errorCode), "dictionary insertion error : %s", ZSTD_getErrorName(errorCode));
errorCode = ZSTD_duplicateCCtx(ctx, refCtx);
CHECK (ZSTD_isError(errorCode), "context duplication error : %s", ZSTD_getErrorName(errorCode));
totalTestSize = 0; cSize = 0;
for (n=0; n<nbChunks; n++)
{
sampleSizeLog = FUZ_rand(&lseed) % maxSampleLog;
sampleSize = (size_t)1 << sampleSizeLog;
sampleSize += FUZ_rand(&lseed) & (sampleSize-1);
sampleStart = FUZ_rand(&lseed) % (srcBufferSize - sampleSize);
if (cBufferSize-cSize < ZSTD_compressBound(sampleSize))
/* avoid invalid dstBufferTooSmall */
break;
if (totalTestSize+sampleSize > maxTestSize) break;
errorCode = ZSTD_compressContinue(ctx, cBuffer+cSize, cBufferSize-cSize, srcBuffer+sampleStart, sampleSize);
CHECK (ZSTD_isError(errorCode), "multi-segments compression error : %s", ZSTD_getErrorName(errorCode));
cSize += errorCode;
XXH64_update(xxh64, srcBuffer+sampleStart, sampleSize);
memcpy(mirrorBuffer + totalTestSize, srcBuffer+sampleStart, sampleSize);
totalTestSize += sampleSize;
}
errorCode = ZSTD_compressEnd(ctx, cBuffer+cSize, cBufferSize-cSize);
CHECK (ZSTD_isError(errorCode), "multi-segments epilogue error : %s", ZSTD_getErrorName(errorCode));
cSize += errorCode;
crcOrig = XXH64_digest(xxh64);
/* streaming decompression test */
errorCode = ZSTD_resetDCtx(dctx);
CHECK (ZSTD_isError(errorCode), "cannot init DCtx : %s", ZSTD_getErrorName(errorCode));
ZSTD_decompress_insertDictionary(dctx, dict, dictSize);
totalCSize = 0;
totalGenSize = 0;
while (totalCSize < cSize)
{
size_t inSize = ZSTD_nextSrcSizeToDecompress(dctx);
size_t genSize = ZSTD_decompressContinue(dctx, dstBuffer+totalGenSize, dstBufferSize-totalGenSize, cBuffer+totalCSize, inSize);
CHECK (ZSTD_isError(genSize), "streaming decompression error : %s", ZSTD_getErrorName(genSize));
totalGenSize += genSize;
totalCSize += inSize;
}
CHECK (ZSTD_nextSrcSizeToDecompress(dctx) != 0, "frame not fully decoded");
CHECK (totalGenSize != totalTestSize, "decompressed data : wrong size")
CHECK (totalCSize != cSize, "compressed data should be fully read")
crcDest = XXH64(dstBuffer, totalTestSize, 0);
if (crcDest!=crcOrig)
errorCode = findDiff(mirrorBuffer, dstBuffer, totalTestSize);
CHECK (crcDest!=crcOrig, "streaming decompressed data corrupted : byte %u / %u (%02X!=%02X)",
(U32)errorCode, (U32)totalTestSize, dstBuffer[errorCode], mirrorBuffer[errorCode]);
}
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 notDone = 1;
while (notDone) {
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 (hSize != 0) {
size_t const toLoad = hSize - zbd->lhSize; /* if hSize!=0, hSize > zbd->lhSize */
if (ZSTD_isError(hSize)) return hSize;
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; ip = iend; notDone = 0;
*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;
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;
} }
/* Frame header instruct buffer sizes */
{ size_t const blockSize = MIN(1 << zbd->fParams.windowLog, ZSTD_BLOCKSIZE_MAX);
zbd->blockSize = blockSize;
if (zbd->inBuffSize < blockSize) {
free(zbd->inBuff);
zbd->inBuffSize = blockSize;
zbd->inBuff = (char*)malloc(blockSize);
if (zbd->inBuff == NULL) return ERROR(memory_allocation);
}
{ size_t const neededOutSize = ((size_t)1 << zbd->fParams.windowLog) + blockSize;
if (zbd->outBuffSize < neededOutSize) {
free(zbd->outBuff);
zbd->outBuffSize = neededOutSize;
zbd->outBuff = (char*)malloc(neededOutSize);
if (zbd->outBuff == NULL) return ERROR(memory_allocation);
} } }
zbd->stage = ZBUFFds_read;
case ZBUFFds_read:
{ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zbd->zd);
if (neededInSize==0) { /* end of frame */
zbd->stage = ZBUFFds_init;
notDone = 0;
break;
}
if ((size_t)(iend-ip) >= neededInSize) { /* decode directly from src */
size_t const decodedSize = ZSTD_decompressContinue(zbd->zd,
zbd->outBuff + zbd->outStart, zbd->outBuffSize - zbd->outStart,
ip, neededInSize);
if (ZSTD_isError(decodedSize)) return decodedSize;
ip += neededInSize;
if (!decodedSize) break; /* this was just a header */
zbd->outEnd = zbd->outStart + decodedSize;
zbd->stage = ZBUFFds_flush;
break;
}
if (ip==iend) { notDone = 0; break; } /* no more input */
zbd->stage = ZBUFFds_load;
}
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) { notDone = 0; break; } /* not enough input, wait for more */
/* decode loaded input */
{ 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) { zbd->stage = ZBUFFds_read; break; } /* this was just a header */
zbd->outEnd = zbd->outStart + decodedSize;
zbd->stage = ZBUFFds_flush;
// break; /* ZBUFFds_flush follows */
} }
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) {
zbd->stage = ZBUFFds_read;
if (zbd->outStart + zbd->blockSize > zbd->outBuffSize)
zbd->outStart = zbd->outEnd = 0;
break;
}
/* cannot flush everything */
notDone = 0;
break;
}
default: return ERROR(GENERIC); /* impossible */
} }
/* result */
*srcSizePtr = ip-istart;
*dstCapacityPtr = op-ostart;
{ size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zbd->zd);
if (nextSrcSizeHint > ZSTD_blockHeaderSize) nextSrcSizeHint+= ZSTD_blockHeaderSize; /* get following block header too */
nextSrcSizeHint -= zbd->inPos; /* already loaded*/
return nextSrcSizeHint;
}
}
