ddidderr/zstd-rs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

changed long length format

Browse Source
This commit is contained in:
Yann Collet
2016-02-02 17:30:37 +01:00
parent 7a6343fb1b
commit 7d8e6bddb9
2 changed files with 21 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/zstd_compress.c
+15 -3
View File
@@ -718,7 +718,7 @@ _check_compressibility:
*/ */
MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals, size_t offsetCode, size_t matchCode) MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals, size_t offsetCode, size_t matchCode)
{ {
#if 0 #if 0 /* for debug */
static const BYTE* g_start = NULL; static const BYTE* g_start = NULL;
if (g_start==NULL) g_start = literals; if (g_start==NULL) g_start = literals;
//if (literals - g_start == 8695) //if (literals - g_start == 8695)
@@ -737,7 +737,13 @@ MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const B
*(seqStorePtr->dumps++) = (BYTE)(litLength - MaxLL); *(seqStorePtr->dumps++) = (BYTE)(litLength - MaxLL);
} else { } else {
*(seqStorePtr->dumps++) = 255; *(seqStorePtr->dumps++) = 255;
MEM_writeLE32(seqStorePtr->dumps, (U32)litLength); seqStorePtr->dumps += 3; if (litLength < (1<<15)) {
MEM_writeLE16(seqStorePtr->dumps, (U16)(litLength<<1));
seqStorePtr->dumps += 2;
} else {
MEM_writeLE32(seqStorePtr->dumps, (U32)((litLength<<1)+1));
seqStorePtr->dumps += 3;
}
} } } }
else *(seqStorePtr->litLength++) = (BYTE)litLength; else *(seqStorePtr->litLength++) = (BYTE)litLength;
@@ -751,7 +757,13 @@ MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const B
*(seqStorePtr->dumps++) = (BYTE)(matchCode - MaxML); *(seqStorePtr->dumps++) = (BYTE)(matchCode - MaxML);
} else { } else {
*(seqStorePtr->dumps++) = 255; *(seqStorePtr->dumps++) = 255;
MEM_writeLE32(seqStorePtr->dumps, (U32)matchCode); seqStorePtr->dumps += 3; if (matchCode < (1<<15)) {
MEM_writeLE16(seqStorePtr->dumps, (U16)(matchCode<<1));
seqStorePtr->dumps += 2;
} else {
MEM_writeLE32(seqStorePtr->dumps, (U32)((matchCode<<1)+1));
seqStorePtr->dumps += 3;
}
} } } }
else *(seqStorePtr->matchLength++) = (BYTE)matchCode; else *(seqStorePtr->matchLength++) = (BYTE)matchCode;
} }
lib/zstd_decompress.c
+6 -4
View File
@@ -626,8 +626,9 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
U32 add = *dumps++; U32 add = *dumps++;
if (add < 255) litLength += add; if (add < 255) litLength += add;
else { else {
litLength = MEM_readLE32(dumps) & 0xFFFFFF; /* no pb : dumps is always followed by seq tables > 1 byte */ litLength = MEM_readLE32(dumps) & 0xFFFFFF; /* no risk : dumps is always followed by seq tables > 1 byte */
dumps += 3; if (litLength&1) litLength>>=1, dumps += 3;
else litLength = (U16)(litLength)>>1, dumps += 2;
} }
if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */ if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */
} }
@@ -659,7 +660,8 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
if (add < 255) matchLength += add; if (add < 255) matchLength += add;
else { else {
matchLength = MEM_readLE32(dumps) & 0xFFFFFF; /* no pb : dumps is always followed by seq tables > 1 byte */ matchLength = MEM_readLE32(dumps) & 0xFFFFFF; /* no pb : dumps is always followed by seq tables > 1 byte */
dumps += 3; if (matchLength&1) matchLength>>=1, dumps += 3;
else matchLength = (U16)(matchLength)>>1, dumps += 2;
} }
if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */ if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */
} }
@@ -671,7 +673,7 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
seq->matchLength = matchLength; seq->matchLength = matchLength;
seqState->dumps = dumps; seqState->dumps = dumps;
#if 0 #if 0 /* debug */
{ {
static U64 totalDecoded = 0; static U64 totalDecoded = 0;
printf("pos %6u : %3u literals & match %3u bytes at distance %6u \n", printf("pos %6u : %3u literals & match %3u bytes at distance %6u \n",