facebook
/
zstd
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

delayed decompression

dev
Yann Collet 2016-11-23 15:11:07 -08:00
parent 271f689139
commit 50524bf0da
1 changed files with 23 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
lib/decompress/zstd_decompress.c
View File

@ -1013,7 +1013,9 @@ static size_t ZSTD_decompressSequences(
/* Regen sequences */ /* Regen sequences */
if (nbSeq) { if (nbSeq) {
seq_t sequences[4];
seqState_t seqState; seqState_t seqState;
int seqNb;
dctx->fseEntropy = 1; dctx->fseEntropy = 1;
{ U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->rep[i]; } { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->rep[i]; }
CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend-ip), corruption_detected); CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend-ip), corruption_detected);
@ -1021,16 +1023,31 @@ static size_t ZSTD_decompressSequences(
FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr);
FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr);
for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) { /* prepare in advance */
nbSeq--; int const seqAdvance = MIN(nbSeq, 3);
{ seq_t const sequence = ZSTD_decodeSequence(&seqState); for (seqNb=0; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb<seqAdvance; seqNb++) {
size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd); sequences[seqNb] = ZSTD_decodeSequence(&seqState);
}
if (seqNb<seqAdvance) return ERROR(corruption_detected);
/* decode and decompress */
for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb<nbSeq ; seqNb++) {
seq_t const sequence = ZSTD_decodeSequence(&seqState);
size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[(seqNb-3) & 3], &litPtr, litEnd, base, vBase, dictEnd);
if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
sequences[seqNb&3] = sequence;
op += oneSeqSize;
}
if (seqNb<nbSeq) return ERROR(corruption_detected);
/* finish queue */
seqNb -=seqAdvance;
for ( ; seqNb<nbSeq ; seqNb++) {
{ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[seqNb&3], &litPtr, litEnd, base, vBase, dictEnd);
if (ZSTD_isError(oneSeqSize)) return oneSeqSize; if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
op += oneSeqSize; op += oneSeqSize;
} } } }
/* check if reached exact end */
if (nbSeq) return ERROR(corruption_detected);
/* save reps for next block */ /* save reps for next block */
{ U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->rep[i] = (U32)(seqState.prevOffset[i]); } { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->rep[i] = (U32)(seqState.prevOffset[i]); }
} }