mirrors/zstd
0
0
Fork 0
mirror of https://github.com/facebook/zstd.git synced 2025-01-19 18:10:32 +08:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #262 from ebiggers/misc_updates

Browse Source 
Miscellaneous updates
This commit is contained in:
Yann Collet 2016-07-27 01:25:45 +02:00 committed by GitHub
commit 04cdd8660d
2 changed files with 14 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
lib/compress/zstd_compress.c
View File

@ -2311,19 +2311,19 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
U32 const dictIDSizeCode = (dictID>0) + (dictID>=256) + (dictID>=65536); /* 0-3 */
U32 const checksumFlag = params.fParams.checksumFlag>0;
U32 const windowSize = 1U << params.cParams.windowLog;
U32 const directModeFlag = params.fParams.contentSizeFlag && (windowSize > (pledgedSrcSize-1));
U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize > (pledgedSrcSize-1));
BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
U32 const fcsCode = params.fParams.contentSizeFlag ?
(pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) : /* 0-3 */
0;
BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (directModeFlag<<5) + (fcsCode<<6) );
BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (singleSegment<<5) + (fcsCode<<6) );
size_t pos;
if (dstCapacity < ZSTD_frameHeaderSize_max) return ERROR(dstSize_tooSmall);
MEM_writeLE32(dst, ZSTD_MAGICNUMBER);
op[4] = frameHeaderDecriptionByte; pos=5;
if (!directModeFlag) op[pos++] = windowLogByte;
if (!singleSegment) op[pos++] = windowLogByte;
switch(dictIDSizeCode)
{
default: /* impossible */
@ -2335,7 +2335,7 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
switch(fcsCode)
{
default: /* impossible */
case 0 : if (directModeFlag) op[pos++] = (BYTE)(pledgedSrcSize); break;
case 0 : if (singleSegment) op[pos++] = (BYTE)(pledgedSrcSize); break;
case 1 : MEM_writeLE16(op+pos, (U16)(pledgedSrcSize-256)); pos+=2; break;
case 2 : MEM_writeLE32(op+pos, (U32)(pledgedSrcSize)); pos+=4; break;
case 3 : MEM_writeLE64(op+pos, (U64)(pledgedSrcSize)); pos+=8; break;

19
lib/decompress/zstd_decompress.c
View File

@ -204,10 +204,10 @@ static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
if (srcSize < ZSTD_frameHeaderSize_min) return ERROR(srcSize_wrong);
{ BYTE const fhd = ((const BYTE*)src)[4];
U32 const dictID= fhd & 3;
U32 const directMode = (fhd >> 5) & 1;
U32 const singleSegment = (fhd >> 5) & 1;
U32 const fcsId = fhd >> 6;
return ZSTD_frameHeaderSize_min + !directMode + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId]
+ (directMode && !ZSTD_fcs_fieldSize[fcsId]);
return ZSTD_frameHeaderSize_min + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId]
+ (singleSegment && !ZSTD_fcs_fieldSize[fcsId]);
}
}
@ -241,14 +241,14 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
size_t pos = 5;
U32 const dictIDSizeCode = fhdByte&3;
U32 const checksumFlag = (fhdByte>>2)&1;
U32 const directMode = (fhdByte>>5)&1;
U32 const singleSegment = (fhdByte>>5)&1;
U32 const fcsID = fhdByte>>6;
U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX;
U32 windowSize = 0;
U32 dictID = 0;
U64 frameContentSize = 0;
if ((fhdByte & 0x08) != 0) return ERROR(frameParameter_unsupported); /* reserved bits, which must be zero */
if (!directMode) {
if (!singleSegment) {
BYTE const wlByte = ip[pos++];
U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
if (windowLog > ZSTD_WINDOWLOG_MAX) return ERROR(frameParameter_unsupported);
@ -267,7 +267,7 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
switch(fcsID)
{
default: /* impossible */
case 0 : if (directMode) frameContentSize = ip[pos]; break;
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;
@ -849,7 +849,6 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
const void* src, size_t srcSize)
{
const BYTE* ip = (const BYTE*)src;
const BYTE* const iend = ip + srcSize;
BYTE* const ostart = (BYTE* const)dst;
BYTE* const oend = ostart + dstCapacity;
BYTE* op = ostart;
@ -860,9 +859,11 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
/* Frame Header */
{ size_t const frameHeaderSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_min);
size_t result;
if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
if (srcSize < frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
if (ZSTD_decodeFrameHeader(dctx, src, frameHeaderSize)) return ERROR(corruption_detected);
result = ZSTD_decodeFrameHeader(dctx, src, frameHeaderSize);
if (ZSTD_isError(result)) return result;
ip += frameHeaderSize; remainingSize -= frameHeaderSize;
}
@ -870,7 +871,7 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
while (1) {
size_t decodedSize;
blockProperties_t blockProperties;
size_t const cBlockSize = ZSTD_getcBlockSize(ip, iend-ip, &blockProperties);
size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
if (ZSTD_isError(cBlockSize)) return cBlockSize;
ip += ZSTD_blockHeaderSize;