ddidderr/zstd-rs
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Literals header fields use little endian convention

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This commit is contained in:
Yann Collet
2016-07-22 14:37:09 +02:00
parent 6fa05a2371
commit 198e6aac44
3 changed files with 95 additions and 89 deletions
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lib/compress/zstd_compress.c
+23 -32
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@@ -572,17 +572,14 @@ static size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void
switch(flSize)
{
case 1: /* 2 - 1 - 5 */
ostart[0] = (BYTE)((lbt_raw<<6) + (0<<5) + srcSize);
ostart[0] = (BYTE)((U32)lbt_raw + (srcSize<<3));
break;
case 2: /* 2 - 2 - 12 */
ostart[0] = (BYTE)((lbt_raw<<6) + (2<<4) + (srcSize >> 8));
ostart[1] = (BYTE)srcSize;
MEM_writeLE16(ostart, (U32)lbt_raw + (1<<2) + (srcSize<<4));
break;
default: /*note : should not be necessary : flSize is within {1,2,3} */
case 3: /* 2 - 2 - 20 */
ostart[0] = (BYTE)((lbt_raw<<6) + (3<<4) + (srcSize >> 16));
ostart[1] = (BYTE)(srcSize>>8);
ostart[2] = (BYTE)srcSize;
MEM_writeLE32(ostart, (U32)lbt_raw + (3<<2) + (srcSize<<4));
break;
}
@@ -595,22 +592,19 @@ static size_t ZSTD_compressRleLiteralsBlock (void* dst, size_t dstCapacity, cons
BYTE* const ostart = (BYTE* const)dst;
U32 const flSize = 1 + (srcSize>31) + (srcSize>4095);
(void)dstCapacity; /* dstCapacity guaranteed to be >=4, hence large enough */
(void)dstCapacity; /* dstCapacity already guaranteed to be >=4, hence large enough */
switch(flSize)
{
case 1: /* 2 - 1 - 5 */
ostart[0] = (BYTE)((lbt_rle<<6) + (0<<5) + srcSize);
ostart[0] = (BYTE)((U32)lbt_rle + (srcSize<<3));
break;
case 2: /* 2 - 2 - 12 */
ostart[0] = (BYTE)((lbt_rle<<6) + (2<<4) + (srcSize >> 8));
ostart[1] = (BYTE)srcSize;
MEM_writeLE16(ostart, (U32)lbt_rle + (1<<2) + (srcSize<<4));
break;
default: /*note : should not be necessary : flSize is necessarily within {1,2,3} */
case 3: /* 2 - 2 - 20 */
ostart[0] = (BYTE)((lbt_rle<<6) + (3<<4) + (srcSize >> 16));
ostart[1] = (BYTE)(srcSize>>8);
ostart[2] = (BYTE)srcSize;
MEM_writeLE32(ostart, (U32)lbt_rle + (3<<2) + (srcSize<<4));
break;
}
@@ -658,24 +652,22 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
switch(lhSize)
{
case 3: /* 2 - 2 - 10 - 10 */
ostart[0] = (BYTE)((srcSize>>6) + (singleStream << 4) + (hType<<6));
ostart[1] = (BYTE)((srcSize<<2) + (cLitSize>>8));
ostart[2] = (BYTE)(cLitSize);
break;
{ U32 const lhc = hType + (singleStream << 2) + (srcSize<<4) + (cLitSize<<14);
MEM_writeLE24(ostart, lhc);
break;
}
case 4: /* 2 - 2 - 14 - 14 */
ostart[0] = (BYTE)((srcSize>>10) + (2<<4) + (hType<<6));
ostart[1] = (BYTE)(srcSize>> 2);
ostart[2] = (BYTE)((srcSize<<6) + (cLitSize>>8));
ostart[3] = (BYTE)(cLitSize);
break;
{ U32 const lhc = hType + (2 << 2) + (srcSize<<4) + (cLitSize<<18);
MEM_writeLE32(ostart, lhc);
break;
}
default: /* should not be necessary, lhSize is only {3,4,5} */
case 5: /* 2 - 2 - 18 - 18 */
ostart[0] = (BYTE)((srcSize>>14) + (3<<4) + (hType<<6));
ostart[1] = (BYTE)(srcSize>>6);
ostart[2] = (BYTE)((srcSize<<2) + (cLitSize>>16));
ostart[3] = (BYTE)(cLitSize>>8);
ostart[4] = (BYTE)(cLitSize);
break;
{ U32 const lhc = hType + (3 << 2) + (srcSize<<4) + (cLitSize<<22);
MEM_writeLE32(ostart, lhc);
ostart[4] = (BYTE)(cLitSize >> 10);
break;
}
}
return lhSize+cLitSize;
}
@@ -2735,8 +2727,7 @@ size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
BYTE* op = (BYTE*)dst;
size_t fhSize = 0;
/* not even init ! */
if (cctx->stage==0) return ERROR(stage_wrong);
if (cctx->stage==0) return ERROR(stage_wrong); /*< not even init ! */
/* special case : empty frame */
if (cctx->stage==1) {
@@ -2748,7 +2739,7 @@ size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
}
/* frame epilogue */
if (dstCapacity < 3) return ERROR(dstSize_tooSmall);
if (dstCapacity < ZSTD_blockHeaderSize) return ERROR(dstSize_tooSmall);
{ U32 const checksum = cctx->params.fParams.checksumFlag ?
(U32)(XXH64_digest(&cctx->xxhState) >> 11) :
0;
@@ -2756,7 +2747,7 @@ size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
}
cctx->stage = 0; /* return to "created but not init" status */
return 3+fhSize;
return ZSTD_blockHeaderSize+fhSize;
}