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

Check repIndex for validity

Browse Source
This commit is contained in:
Yann Collet
2016-06-13 21:43:06 +02:00
parent 3eb52578f3
commit 43dfe01919
2 changed files with 133 additions and 126 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/compress/zstd_compress.c
+22 -19
View File
@@ -1129,13 +1129,13 @@ void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* zc,
while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
size_t mlCode;
size_t offset;
const size_t h = ZSTD_hashPtr(ip, hBits, mls);
const U32 matchIndex = hashTable[h];
size_t const h = ZSTD_hashPtr(ip, hBits, mls);
U32 const current = (U32)(ip-base);
U32 const matchIndex = hashTable[h];
const BYTE* match = base + matchIndex;
const U32 current = (U32)(ip-base);
hashTable[h] = current; /* update hash table */
if (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1)) { /* note : by construction, offset_1 <= current */
if ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1))) { /* note : by construction, offset_1 <= current */
mlCode = ZSTD_count(ip+1+EQUAL_READ32, ip+1+EQUAL_READ32-offset_1, iend) + EQUAL_READ32;
ip++;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, 0, mlCode-MINMATCH);
@@ -1164,7 +1164,8 @@ void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* zc,
hashTable[ZSTD_hashPtr(ip-2, hBits, mls)] = (U32)(ip-2-base);
/* check immediate repcode */
while ( (ip <= ilimit)
&& (MEM_read32(ip) == MEM_read32(ip - offset_2)) ) {
&& ( (offset>0)
& (MEM_read32(ip) == MEM_read32(ip - offset_2)) )) {
/* store sequence */
size_t const rlCode = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-offset_2, iend) + EQUAL_READ32;
{ size_t const tmpOff = offset_2; offset_2 = offset_1; offset_1 = tmpOff; } /* swap offset_2 <=> offset_1 */
@@ -1214,8 +1215,8 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const U32 lowLimit = ctx->lowLimit;
const BYTE* const dictStart = dictBase + lowLimit;
const U32 lowestIndex = ctx->lowLimit;
const BYTE* const dictStart = dictBase + lowestIndex;
const U32 dictLimit = ctx->dictLimit;
const BYTE* const lowPrefixPtr = base + dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
@@ -1245,14 +1246,14 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
U32 offset;
hashTable[h] = current; /* update hash table */
if ( ((repIndex >= dictLimit) || (repIndex <= dictLimit-4))
if ( ((repIndex >= dictLimit) | ((repIndex <= dictLimit-4) & (repIndex>lowestIndex)))
&& (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
const BYTE* repMatchEnd = repIndex < dictLimit ? dictEnd : iend;
mlCode = ZSTD_count_2segments(ip+1+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repMatchEnd, lowPrefixPtr) + EQUAL_READ32;
ip++;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, 0, mlCode-MINMATCH);
} else {
if ( (matchIndex < lowLimit) ||
if ( (matchIndex < lowestIndex) ||
(MEM_read32(match) != MEM_read32(ip)) ) {
ip += ((ip-anchor) >> g_searchStrength) + 1;
continue;
@@ -1280,7 +1281,7 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
U32 const current2 = (U32)(ip-base);
U32 const repIndex2 = current2 - offset_2;
const BYTE* repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2;
if ( ((repIndex2 <= dictLimit-4) || (repIndex2 >= dictLimit))
if ( ( ((repIndex2>lowestIndex) & (repIndex2 <= dictLimit-4)) | (repIndex2 >= dictLimit) )
&& (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
const BYTE* const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend;
size_t repLength2 = ZSTD_count_2segments(ip+EQUAL_READ32, repMatch2+EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32;
@@ -1721,7 +1722,7 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
size_t* offsetPtr,
U32 maxNbAttempts, U32 matchLengthSearch);
searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS;
searchMax_f const searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS;
/* init */
U32 rep[ZSTD_REP_INIT];
@@ -1738,7 +1739,7 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
const BYTE* start=ip+1;
/* check repCode */
if (MEM_read32(ip+1) == MEM_read32(ip+1 - rep[0])) {
if ((rep[0]>0) & (MEM_read32(ip+1) == MEM_read32(ip+1 - rep[0]))) {
/* repcode : we take it */
matchLength = ZSTD_count(ip+1+EQUAL_READ32, ip+1+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
if (depth==0) goto _storeSequence;
@@ -1760,7 +1761,7 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
if (depth>=1)
while (ip<ilimit) {
ip ++;
if ((offset) && (MEM_read32(ip) == MEM_read32(ip - rep[0]))) {
if ((offset) && ((rep[0]>0) & (MEM_read32(ip) == MEM_read32(ip - rep[0])))) {
size_t const mlRep = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
int const gain2 = (int)(mlRep * 3);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
@@ -1779,7 +1780,7 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
/* let's find an even better one */
if ((depth==2) && (ip<ilimit)) {
ip ++;
if ((offset) && (MEM_read32(ip) == MEM_read32(ip - rep[0]))) {
if ((offset) && ((rep[0]>0) & (MEM_read32(ip) == MEM_read32(ip - rep[0])))) {
size_t const ml2 = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[0], iend) + EQUAL_READ32;
int const gain2 = (int)(ml2 * 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
@@ -1813,7 +1814,8 @@ _storeSequence:
/* check immediate repcode */
while ( (ip <= ilimit)
&& (MEM_read32(ip) == MEM_read32(ip - rep[1])) ) {
&& ((rep[1]>0)
& (MEM_read32(ip) == MEM_read32(ip - rep[1])) )) {
/* store sequence */
matchLength = ZSTD_count(ip+EQUAL_READ32, ip+EQUAL_READ32-rep[1], iend) + EQUAL_READ32;
offset = rep[1]; rep[1] = rep[0]; rep[0] = (U32)offset; /* swap repcodes */
@@ -1866,6 +1868,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
const BYTE* const ilimit = iend - 8;
const BYTE* const base = ctx->base;
const U32 dictLimit = ctx->dictLimit;
const U32 lowestIndex = ctx->lowLimit;
const BYTE* const prefixStart = base + dictLimit;
const BYTE* const dictBase = ctx->dictBase;
const BYTE* const dictEnd = dictBase + dictLimit;
@@ -1899,7 +1902,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
const U32 repIndex = (U32)(current+1 - rep[0]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip+1) == MEM_read32(repMatch)) {
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
@@ -1929,7 +1932,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
const U32 repIndex = (U32)(current - rep[0]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip) == MEM_read32(repMatch)) {
/* repcode detected */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
@@ -1959,7 +1962,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
const U32 repIndex = (U32)(current - rep[0]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip) == MEM_read32(repMatch)) {
/* repcode detected */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
@@ -2003,7 +2006,7 @@ _storeSequence:
const U32 repIndex = (U32)((ip-base) - rep[1]);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if ((U32)((dictLimit-1) - repIndex) >= 3) /* intentional overflow */
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip) == MEM_read32(repMatch)) {
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;