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-rw-r--r--lz4frame.c64
1 files changed, 49 insertions, 15 deletions
diff --git a/lz4frame.c b/lz4frame.c
index 0b54840..390af0e 100644
--- a/lz4frame.c
+++ b/lz4frame.c
@@ -407,7 +407,6 @@ size_t LZ4F_compressUpdate(LZ4F_compressionContext_t compressionContext, void* d
int (*compress)(void*, const char*, char*, int, int);
-
if (cctxPtr->cStage != 1) return -ERROR_GENERIC;
if (dstMaxSize < LZ4F_compressBound(srcSize, &(cctxPtr->prefs))) return -ERROR_dstMaxSize_tooSmall;
if (compressOptionsPtr == NULL) compressOptionsPtr = &cOptionsNull;
@@ -681,7 +680,6 @@ static size_t LZ4F_decodeHeader(LZ4F_dctx_internal_t* dctxPtr, const BYTE* srcPt
/* validate */
if (version != 1) return -ERROR_GENERIC; /* Version Number, only supported value */
- //if (blockMode != blockIndependent) return -ERROR_GENERIC; /* Only supported blockMode for the time being */
if (blockChecksumFlag != 0) return -ERROR_GENERIC; /* Only supported value for the time being */
if (contentSizeFlag != 0) return -ERROR_GENERIC; /* Only supported value for the time being */
if (((FLG>>1)&_1BIT) != 0) return -ERROR_GENERIC; /* Reserved bit */
@@ -700,7 +698,7 @@ static size_t LZ4F_decodeHeader(LZ4F_dctx_internal_t* dctxPtr, const BYTE* srcPt
if (contentChecksumFlag) XXH32_resetState(&(dctxPtr->xxh), 0);
/* alloc */
- bufferNeeded = dctxPtr->maxBlockSize + ((dctxPtr->frameInfo.blockMode==blockLinked) * 64 KB);
+ bufferNeeded = dctxPtr->maxBlockSize + ((dctxPtr->frameInfo.blockMode==blockLinked) * 128 KB);
if (bufferNeeded > dctxPtr->maxBufferSize) /* tmp buffers too small */
{
FREEMEM(dctxPtr->tmpIn);
@@ -711,10 +709,9 @@ static size_t LZ4F_decodeHeader(LZ4F_dctx_internal_t* dctxPtr, const BYTE* srcPt
dctxPtr->tmpOutBuffer= ALLOCATOR(dctxPtr->maxBufferSize);
if (dctxPtr->tmpOutBuffer== NULL) return -ERROR_GENERIC;
}
- dctxPtr->tmpOut = dctxPtr->tmpOutBuffer;
- if (dctxPtr->frameInfo.blockMode==blockLinked) dctxPtr->tmpOut += 64 KB;
+ dctxPtr->dict = dctxPtr->tmpOutBuffer;
dctxPtr->dictSize = 0;
- dctxPtr->dict = dctxPtr->tmpOut;
+ dctxPtr->tmpOut = dctxPtr->tmpOutBuffer;
return 7;
}
@@ -765,11 +762,46 @@ static void LZ4F_saveDict(LZ4F_dctx_internal_t* dctxPtr, const BYTE* decoded, si
size_t preserveDictSize;
if (newDictSize > 64 KB) newDictSize = 64 KB;
preserveDictSize = 64 KB - newDictSize;
- memmove(dctxPtr->tmpOutBuffer, dctxPtr->tmpOutBuffer + newDictSize, preserveDictSize);
- memcpy(dctxPtr->tmpOutBuffer + preserveDictSize, decoded + decodedSize - newDictSize, newDictSize);
- dctxPtr->dictSize += newDictSize;
- if (dctxPtr->dictSize > 64 KB) dctxPtr->dictSize = 64 KB;
- dctxPtr->dict = dctxPtr->tmpOut - dctxPtr->dictSize;
+ if (preserveDictSize > dctxPtr->dictSize) preserveDictSize = dctxPtr->dictSize;
+
+ memmove(dctxPtr->tmpOutBuffer, dctxPtr->dict + dctxPtr->dictSize - preserveDictSize, preserveDictSize);
+ memmove(dctxPtr->tmpOutBuffer + preserveDictSize, decoded + decodedSize - newDictSize, newDictSize);
+
+ dctxPtr->dict = dctxPtr->tmpOutBuffer;
+ dctxPtr->dictSize = preserveDictSize + newDictSize;
+ dctxPtr->tmpOut = dctxPtr->tmpOutBuffer + dctxPtr->dictSize;
+}
+
+
+static void LZ4F_pointDict(LZ4F_dctx_internal_t* dctxPtr, const BYTE* decoded, size_t decodedSize)
+{
+ /* large decoded block */
+ if (decodedSize >= (64 KB - 1))
+ {
+ dctxPtr->dict = (BYTE*)decoded;
+ dctxPtr->dictSize = decodedSize;
+ dctxPtr->tmpOut = dctxPtr->tmpOutBuffer + 64 KB;
+ return;
+ }
+
+ /* decoded block in the continuity of dictionary */
+ if (dctxPtr->dict + dctxPtr->dictSize == decoded)
+ {
+ dctxPtr->dictSize += decodedSize;
+ if (dctxPtr->dict == dctxPtr->tmpOutBuffer) /* extended tmp buffer, don't go beyond 128 KB == maxDictSize */
+ {
+ if (dctxPtr->dictSize > 128 KB)
+ {
+ memcpy(dctxPtr->tmpOutBuffer, dctxPtr->tmpOutBuffer + dctxPtr->dictSize - 64 KB, 64 KB);
+ dctxPtr->dictSize = 64 KB;
+ }
+ dctxPtr->tmpOut = dctxPtr->tmpOutBuffer + dctxPtr->dictSize;
+ }
+ return;
+ }
+
+ /* small block, and not contiguous : let's save that */
+ LZ4F_saveDict(dctxPtr, decoded, decodedSize);
}
@@ -931,7 +963,7 @@ size_t LZ4F_decompress(LZ4F_decompressionContext_t decompressionContext,
if ((size_t)(dstEnd-dstPtr) < sizeToCopy) sizeToCopy = dstEnd - dstPtr;
memcpy(dstPtr, srcPtr, sizeToCopy);
if (dctxPtr->frameInfo.contentChecksumFlag) XXH32_update(&(dctxPtr->xxh), srcPtr, sizeToCopy);
- if (dctxPtr->frameInfo.blockMode==blockLinked) LZ4F_saveDict(dctxPtr, srcPtr, sizeToCopy);
+ if (dctxPtr->frameInfo.blockMode==blockLinked) LZ4F_pointDict(dctxPtr, srcPtr, sizeToCopy);
srcPtr += sizeToCopy;
dstPtr += sizeToCopy;
if (sizeToCopy == dctxPtr->tmpInTarget) /* all copied */
@@ -987,12 +1019,11 @@ size_t LZ4F_decompress(LZ4F_decompressionContext_t decompressionContext,
else
decoder = LZ4F_decompress_safe;
- if ((size_t)(dstEnd-dstPtr) < dctxPtr->maxBlockSize) /* not enough dst room : decode into tmpOut */
+ if ((size_t)(dstEnd-dstPtr) < dctxPtr->maxBlockSize) /* not enough place into dst : decode into tmpOut */
{
decodedSize = decoder((const char*)selectedIn, (char*)dctxPtr->tmpOut, (int)dctxPtr->tmpInTarget, (int)dctxPtr->maxBlockSize, (const char*)dctxPtr->dict, (int)dctxPtr->dictSize);
if (decodedSize < 0) return -ERROR_GENERIC; /* decompression failed */
if (dctxPtr->frameInfo.contentChecksumFlag) XXH32_update(&(dctxPtr->xxh), dctxPtr->tmpOut, decodedSize);
- if (dctxPtr->frameInfo.blockMode==blockLinked) LZ4F_saveDict(dctxPtr, dctxPtr->tmpOut, decodedSize);
dctxPtr->tmpOutSize = decodedSize;
dctxPtr->tmpOutStart = 0;
dctxPtr->dStage = dstage_flushOut;
@@ -1001,7 +1032,7 @@ size_t LZ4F_decompress(LZ4F_decompressionContext_t decompressionContext,
decodedSize = decoder((const char*)selectedIn, (char*)dstPtr, (int)dctxPtr->tmpInTarget, (int)dctxPtr->maxBlockSize, (const char*)dctxPtr->dict, (int)dctxPtr->dictSize);
if (decodedSize < 0) return -ERROR_GENERIC; /* decompression failed */
if (dctxPtr->frameInfo.contentChecksumFlag) XXH32_update(&(dctxPtr->xxh), dstPtr, decodedSize);
- if (dctxPtr->frameInfo.blockMode==blockLinked) LZ4F_saveDict(dctxPtr, dstPtr, decodedSize);
+ if (dctxPtr->frameInfo.blockMode==blockLinked) LZ4F_pointDict(dctxPtr, dstPtr, decodedSize);
dstPtr += decodedSize;
dctxPtr->dStage = dstage_getCBlockSize;
break;
@@ -1016,6 +1047,7 @@ size_t LZ4F_decompress(LZ4F_decompressionContext_t decompressionContext,
dstPtr += sizeToCopy;
if (dctxPtr->tmpOutStart == dctxPtr->tmpOutSize)
{
+ if (dctxPtr->frameInfo.blockMode==blockLinked) LZ4F_pointDict(dctxPtr, dctxPtr->tmpOut, dctxPtr->tmpOutSize);
dctxPtr->dStage = dstage_getCBlockSize;
break;
}
@@ -1077,6 +1109,8 @@ size_t LZ4F_decompress(LZ4F_decompressionContext_t decompressionContext,
}
}
+ if ((dctxPtr->frameInfo.blockMode==blockLinked) && (dctxPtr->dict != dctxPtr->tmpOutBuffer))
+ LZ4F_saveDict(dctxPtr, NULL, 0);
if (srcPtr<srcEnd) /* function must be called again with following source data */
dctxPtr->srcExpect = srcPtr;
generated by cgit v0.12 at 2024-11-17 19:24:10 (GMT)