AuroraMiddleware/lz4
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Avoid dictionary == NULL Check

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This commit is contained in:
W. Felix Handte 2018-01-30 15:22:29 -05:00
parent efc419a6d4
commit d6ed9a7799
1 changed files with 11 additions and 7 deletions
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18
lib/lz4.c
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@ -590,6 +590,7 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
(const BYTE*) source - dictCtx->currentOffset : (const BYTE*) source - dictCtx->currentOffset :
(const BYTE*) source - dictSize - currentOffset; (const BYTE*) source - dictSize - currentOffset;
const ptrdiff_t dictDelta = dictionary ? dictEnd - (const BYTE*) source : 0; const ptrdiff_t dictDelta = dictionary ? dictEnd - (const BYTE*) source : 0;
const BYTE* dictLowLimit;
BYTE* op = (BYTE*) dest; BYTE* op = (BYTE*) dest;
BYTE* const olimit = op + maxOutputSize; BYTE* const olimit = op + maxOutputSize;
@ -619,6 +620,9 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
lowLimit = (const BYTE*)source; lowLimit = (const BYTE*)source;
break; break;
} }
dictLowLimit = dictionary ? dictionary : lowLimit;
if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */ if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */
if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */
@ -653,15 +657,15 @@ LZ4_FORCE_INLINE int LZ4_compress_generic(
/* TODO: use precalc-ed hash? */ /* TODO: use precalc-ed hash? */
match = LZ4_getPosition(ip, dictCtx->hashTable, byU32, dictBase); match = LZ4_getPosition(ip, dictCtx->hashTable, byU32, dictBase);
refDelta = dictDelta; refDelta = dictDelta;
lowLimit = dictionary; lowLimit = dictLowLimit;
} else { } else {
refDelta = 0; refDelta = 0;
lowLimit = (const BYTE*)source; lowLimit = (const BYTE*)source;
} }
} else if (dictDirective==usingExtDict) { } else if (dictDirective==usingExtDict) {
if (match < (const BYTE*)source && dictionary != NULL) { if (match < (const BYTE*)source) {
refDelta = dictDelta; refDelta = dictDelta;
lowLimit = dictionary; lowLimit = dictLowLimit;
} else { } else {
refDelta = 0; refDelta = 0;
lowLimit = (const BYTE*)source; lowLimit = (const BYTE*)source;
@ -703,7 +707,7 @@ _next_match:
/* Encode MatchLength */ /* Encode MatchLength */
{ unsigned matchCode; { unsigned matchCode;
if ((dictDirective==usingExtDict || dictDirective==usingExtDictCtx) && (dictionary != NULL) && (lowLimit==dictionary)) { if ((dictDirective==usingExtDict || dictDirective==usingExtDictCtx) && (dictionary != NULL) && (lowLimit==dictLowLimit)) {
const BYTE* limit; const BYTE* limit;
match += refDelta; match += refDelta;
limit = ip + (dictEnd-match); limit = ip + (dictEnd-match);
@ -754,15 +758,15 @@ _next_match:
/* TODO: use precalc-ed hash? */ /* TODO: use precalc-ed hash? */
match = LZ4_getPosition(ip, dictCtx->hashTable, byU32, dictBase); match = LZ4_getPosition(ip, dictCtx->hashTable, byU32, dictBase);
refDelta = dictDelta; refDelta = dictDelta;
lowLimit = dictionary; lowLimit = dictLowLimit;
} else { } else {
refDelta = 0; refDelta = 0;
lowLimit = (const BYTE*)source; lowLimit = (const BYTE*)source;
} }
} else if (dictDirective==usingExtDict) { } else if (dictDirective==usingExtDict) {
if (match < (const BYTE*)source && dictionary != NULL) { if (match < (const BYTE*)source) {
refDelta = dictDelta; refDelta = dictDelta;
lowLimit = dictionary; lowLimit = dictLowLimit;
} else { } else {
refDelta = 0; refDelta = 0;
lowLimit = (const BYTE*)source; lowLimit = (const BYTE*)source;