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dictionary with block API

dev
Yann Collet 2016-01-09 02:00:10 +01:00
parent bf42c8e5d8
commit b012510d9f
2 changed files with 49 additions and 14 deletions
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43
lib/zstd_decompress.c
View File

@ -658,7 +658,19 @@ static size_t ZSTD_decompressSequences(
}
size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
static void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst)
{
if (dst != dctx->previousDstEnd) /* not contiguous */
{
dctx->dictEnd = dctx->previousDstEnd;
dctx->vBase = (const char*)dst - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base));
dctx->base = dst;
dctx->previousDstEnd = dst;
}
}
static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize,
const void* src, size_t srcSize)
{
@ -675,6 +687,15 @@ size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
}
size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize,
const void* src, size_t srcSize)
{
ZSTD_checkContinuity(dctx, dst);
return ZSTD_decompressBlock_internal(dctx, dst, maxDstSize, src, srcSize);
}
size_t ZSTD_decompress_usingDict(ZSTD_DCtx* ctx,
void* dst, size_t maxDstSize,
const void* src, size_t srcSize,
@ -735,7 +756,7 @@ size_t ZSTD_decompress_usingDict(ZSTD_DCtx* ctx,
switch(blockProperties.blockType)
{
case bt_compressed:
decodedSize = ZSTD_decompressBlock(ctx, op, oend-op, ip, cBlockSize);
decodedSize = ZSTD_decompressBlock_internal(ctx, op, oend-op, ip, cBlockSize);
break;
case bt_raw :
decodedSize = ZSTD_copyRawBlock(op, oend-op, ip, cBlockSize);
@ -786,13 +807,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* ctx, void* dst, size_t maxDstSize, con
{
/* Sanity check */
if (srcSize != ctx->expected) return ERROR(srcSize_wrong);
if (dst != ctx->previousDstEnd) /* not contiguous */
{
ctx->dictEnd = ctx->previousDstEnd;
ctx->vBase = (const char*)dst - ((const char*)(ctx->previousDstEnd) - (const char*)(ctx->base));
ctx->base = dst;
ctx->previousDstEnd = dst;
}
ZSTD_checkContinuity(ctx, dst);
/* Decompress : frame header; part 1 */
switch (ctx->stage)
@ -849,7 +864,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* ctx, void* dst, size_t maxDstSize, con
switch(ctx->bType)
{
case bt_compressed:
rSize = ZSTD_decompressBlock(ctx, dst, maxDstSize, src, srcSize);
rSize = ZSTD_decompressBlock_internal(ctx, dst, maxDstSize, src, srcSize);
break;
case bt_raw :
rSize = ZSTD_copyRawBlock(dst, maxDstSize, src, srcSize);
@ -874,10 +889,10 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* ctx, void* dst, size_t maxDstSize, con
}
void ZSTD_decompress_insertDictionary(ZSTD_DCtx* ctx, const void* src, size_t srcSize)
void ZSTD_decompress_insertDictionary(ZSTD_DCtx* ctx, const void* dict, size_t dictSize)
{
ctx->dictEnd = ctx->previousDstEnd;
ctx->vBase = (const char*)src - ((const char*)(ctx->previousDstEnd) - (const char*)(ctx->base));
ctx->base = src;
ctx->previousDstEnd = (const char*)src + srcSize;
ctx->vBase = (const char*)dict - ((const char*)(ctx->previousDstEnd) - (const char*)(ctx->base));
ctx->base = dict;
ctx->previousDstEnd = (const char*)dict + dictSize;
}

20
programs/fuzzer.c
View File

@ -273,6 +273,7 @@ static int basicUnitTests(U32 seed, double compressibility)
ZSTD_CCtx* const cctx = ZSTD_createCCtx();
ZSTD_DCtx* const dctx = ZSTD_createDCtx();
const size_t blockSize = 100 KB;
const size_t dictSize = 16 KB;
/* basic block compression */
DISPLAYLEVEL(4, "test%3i : Block compression test : ", testNb++);
@ -290,6 +291,25 @@ static int basicUnitTests(U32 seed, double compressibility)
if (result != blockSize) goto _output_error;
DISPLAYLEVEL(4, "OK \n");
/* dictionary block compression */
DISPLAYLEVEL(4, "test%3i : Dictionary Block compression test : ", testNb++);
result = ZSTD_compressBegin(cctx, 5);
if (ZSTD_isError(result)) goto _output_error;
result = ZSTD_compress_insertDictionary(cctx, CNBuffer, dictSize);
if (ZSTD_isError(result)) goto _output_error;
cSize = ZSTD_compressBlock(cctx, compressedBuffer, ZSTD_compressBound(blockSize), (char*)CNBuffer+dictSize, blockSize);
if (ZSTD_isError(cSize)) goto _output_error;
DISPLAYLEVEL(4, "OK \n");
DISPLAYLEVEL(4, "test%3i : Dictionary Block decompression test : ", testNb++);
result = ZSTD_resetDCtx(dctx);
if (ZSTD_isError(result)) goto _output_error;
ZSTD_decompress_insertDictionary(dctx, CNBuffer, dictSize);
result = ZSTD_decompressBlock(dctx, decodedBuffer, COMPRESSIBLE_NOISE_LENGTH, compressedBuffer, cSize);
if (ZSTD_isError(result)) goto _output_error;
if (result != blockSize) goto _output_error;
DISPLAYLEVEL(4, "OK \n");
ZSTD_freeCCtx(cctx);
ZSTD_freeDCtx(dctx);
}