diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c index 197e8ed8a..14b284af0 100644 --- a/lib/compress/zstd_compress.c +++ b/lib/compress/zstd_compress.c @@ -1785,11 +1785,26 @@ static int ZSTD_indexTooCloseToMax(ZSTD_window_t w) return (size_t)(w.nextSrc - w.base) > (ZSTD_CURRENT_MAX - ZSTD_INDEXOVERFLOW_MARGIN); } +/** ZSTD_dictTooBig(): + * When dictionaries are larger than ZSTD_CHUNKSIZE_MAX they can't be loaded in + * one go generically. So we ensure that in that case we reset the tables to zero, + * so that we can load as much of the dictionary as possible. + */ +static int ZSTD_dictTooBig(size_t const loadedDictSize) +{ + return loadedDictSize > ZSTD_CHUNKSIZE_MAX; +} + /*! ZSTD_resetCCtx_internal() : - note : `params` are assumed fully validated at this stage */ + * @param loadedDictSize The size of the dictionary to be loaded + * into the context, if any. If no dictionary is used, or the + * dictionary is being attached / copied, then pass 0. + * note : `params` are assumed fully validated at this stage. + */ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc, ZSTD_CCtx_params params, U64 const pledgedSrcSize, + size_t const loadedDictSize, ZSTD_compResetPolicy_e const crp, ZSTD_buffered_policy_e const zbuff) { @@ -1821,8 +1836,9 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc, size_t const maxNbLdmSeq = ZSTD_ldm_getMaxNbSeq(params.ldmParams, blockSize); int const indexTooClose = ZSTD_indexTooCloseToMax(zc->blockState.matchState.window); + int const dictTooBig = ZSTD_dictTooBig(loadedDictSize); ZSTD_indexResetPolicy_e needsIndexReset = - (!indexTooClose && zc->initialized) ? ZSTDirp_continue : ZSTDirp_reset; + (indexTooClose || dictTooBig || !zc->initialized) ? ZSTDirp_reset : ZSTDirp_continue; size_t const neededSpace = ZSTD_estimateCCtxSize_usingCCtxParams_internal( @@ -1937,7 +1953,6 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc, zc->maxNbLdmSequences = maxNbLdmSeq; ZSTD_window_init(&zc->ldmState.window); - ZSTD_window_clear(&zc->ldmState.window); zc->ldmState.loadedDictEnd = 0; } @@ -2017,6 +2032,7 @@ ZSTD_resetCCtx_byAttachingCDict(ZSTD_CCtx* cctx, params.cParams.windowLog = windowLog; params.useRowMatchFinder = cdict->useRowMatchFinder; /* cdict overrides */ FORWARD_IF_ERROR(ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize, + /* loadedDictSize */ 0, ZSTDcrp_makeClean, zbuff), ""); assert(cctx->appliedParams.cParams.strategy == adjusted_cdict_cParams.strategy); } @@ -2069,6 +2085,7 @@ static size_t ZSTD_resetCCtx_byCopyingCDict(ZSTD_CCtx* cctx, params.cParams.windowLog = windowLog; params.useRowMatchFinder = cdict->useRowMatchFinder; FORWARD_IF_ERROR(ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize, + /* loadedDictSize */ 0, ZSTDcrp_leaveDirty, zbuff), ""); assert(cctx->appliedParams.cParams.strategy == cdict_cParams->strategy); assert(cctx->appliedParams.cParams.hashLog == cdict_cParams->hashLog); @@ -2174,6 +2191,7 @@ static size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx, params.useRowMatchFinder = srcCCtx->appliedParams.useRowMatchFinder; params.fParams = fParams; ZSTD_resetCCtx_internal(dstCCtx, params, pledgedSrcSize, + /* loadedDictSize */ 0, ZSTDcrp_leaveDirty, zbuff); assert(dstCCtx->appliedParams.cParams.windowLog == srcCCtx->appliedParams.cParams.windowLog); assert(dstCCtx->appliedParams.cParams.strategy == srcCCtx->appliedParams.cParams.strategy); @@ -4099,77 +4117,86 @@ static size_t ZSTD_loadDictionaryContent(ZSTD_matchState_t* ms, { const BYTE* ip = (const BYTE*) src; const BYTE* const iend = ip + srcSize; + int const loadLdmDict = params->ldmParams.enableLdm && ls != NULL; + + /* Assert that we the ms params match the params we're being given */ + ZSTD_assertEqualCParams(params->cParams, ms->cParams); + if (srcSize > ZSTD_CHUNKSIZE_MAX) { + /* Allow the dictionary to set indices up to exactly ZSTD_CURRENT_MAX. + * Dictionaries right at the edge will immediately trigger overflow + * correction, but I don't want to insert extra constraints here. + */ + U32 const maxDictSize = ZSTD_CURRENT_MAX - 1; + /* We must have cleared our windows when our source is this large. */ + assert(ZSTD_window_isEmpty(ms->window)); + if (loadLdmDict) + assert(ZSTD_window_isEmpty(ls->window)); + /* If the dictionary is too large, only load the suffix of the dictionary. */ + if (srcSize > maxDictSize) { + ip = iend - maxDictSize; + src = ip; + srcSize = maxDictSize; + } + } DEBUGLOG(4, "ZSTD_loadDictionaryContent(): useRowMatchFinder=%d", (int)params->useRowMatchFinder); ZSTD_window_update(&ms->window, src, srcSize); ms->loadedDictEnd = params->forceWindow ? 0 : (U32)(iend - ms->window.base); - if (params->ldmParams.enableLdm && ls != NULL) { + if (loadLdmDict) { ZSTD_window_update(&ls->window, src, srcSize); ls->loadedDictEnd = params->forceWindow ? 0 : (U32)(iend - ls->window.base); } - /* Assert that we the ms params match the params we're being given */ - ZSTD_assertEqualCParams(params->cParams, ms->cParams); - if (srcSize <= HASH_READ_SIZE) return 0; - while (iend - ip > HASH_READ_SIZE) { - size_t const remaining = (size_t)(iend - ip); - size_t const chunk = MIN(remaining, ZSTD_CHUNKSIZE_MAX); - const BYTE* const ichunk = ip + chunk; + ZSTD_overflowCorrectIfNeeded(ms, ws, params, ip, iend); - ZSTD_overflowCorrectIfNeeded(ms, ws, params, ip, ichunk); + if (loadLdmDict) + ZSTD_ldm_fillHashTable(ls, (const BYTE*)src, (const BYTE*)src + srcSize, ¶ms->ldmParams); - if (params->ldmParams.enableLdm && ls != NULL) - ZSTD_ldm_fillHashTable(ls, (const BYTE*)src, (const BYTE*)src + srcSize, ¶ms->ldmParams); + switch(params->cParams.strategy) + { + case ZSTD_fast: + ZSTD_fillHashTable(ms, iend, dtlm); + break; + case ZSTD_dfast: + ZSTD_fillDoubleHashTable(ms, iend, dtlm); + break; - switch(params->cParams.strategy) - { - case ZSTD_fast: - ZSTD_fillHashTable(ms, ichunk, dtlm); - break; - case ZSTD_dfast: - ZSTD_fillDoubleHashTable(ms, ichunk, dtlm); - break; - - case ZSTD_greedy: - case ZSTD_lazy: - case ZSTD_lazy2: - if (chunk >= HASH_READ_SIZE) { - if (ms->dedicatedDictSearch) { - assert(chunk == remaining); /* must load everything in one go */ - assert(ms->chainTable != NULL); - ZSTD_dedicatedDictSearch_lazy_loadDictionary(ms, ichunk-HASH_READ_SIZE); + case ZSTD_greedy: + case ZSTD_lazy: + case ZSTD_lazy2: + if (srcSize >= HASH_READ_SIZE) { + if (ms->dedicatedDictSearch) { + assert(ms->chainTable != NULL); + ZSTD_dedicatedDictSearch_lazy_loadDictionary(ms, iend-HASH_READ_SIZE); + } else { + assert(params->useRowMatchFinder != ZSTD_urm_auto); + if (params->useRowMatchFinder == ZSTD_urm_enableRowMatchFinder) { + size_t const tagTableSize = ((size_t)1 << params->cParams.hashLog) * sizeof(U16); + if (ip == src) + ZSTD_memset(ms->tagTable, 0, tagTableSize); + ZSTD_row_update(ms, iend-HASH_READ_SIZE); + DEBUGLOG(4, "Using row-based hash table for lazy dict"); } else { - assert(params->useRowMatchFinder != ZSTD_urm_auto); - if (params->useRowMatchFinder == ZSTD_urm_enableRowMatchFinder) { - size_t const tagTableSize = ((size_t)1 << params->cParams.hashLog) * sizeof(U16); - if (ip == src) - ZSTD_memset(ms->tagTable, 0, tagTableSize); - ZSTD_row_update(ms, ichunk-HASH_READ_SIZE); - DEBUGLOG(4, "Using row-based hash table for lazy dict"); - } else { - ZSTD_insertAndFindFirstIndex(ms, ichunk-HASH_READ_SIZE); - DEBUGLOG(4, "Using chain-based hash table for lazy dict"); - } + ZSTD_insertAndFindFirstIndex(ms, iend-HASH_READ_SIZE); + DEBUGLOG(4, "Using chain-based hash table for lazy dict"); } } - break; - - case ZSTD_btlazy2: /* we want the dictionary table fully sorted */ - case ZSTD_btopt: - case ZSTD_btultra: - case ZSTD_btultra2: - if (chunk >= HASH_READ_SIZE) - ZSTD_updateTree(ms, ichunk-HASH_READ_SIZE, ichunk); - break; - - default: - assert(0); /* not possible : not a valid strategy id */ } + break; - ip = ichunk; + case ZSTD_btlazy2: /* we want the dictionary table fully sorted */ + case ZSTD_btopt: + case ZSTD_btultra: + case ZSTD_btultra2: + if (srcSize >= HASH_READ_SIZE) + ZSTD_updateTree(ms, iend-HASH_READ_SIZE, iend); + break; + + default: + assert(0); /* not possible : not a valid strategy id */ } ms->nextToUpdate = (U32)(iend - ms->window.base); @@ -4378,6 +4405,7 @@ static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params, U64 pledgedSrcSize, ZSTD_buffered_policy_e zbuff) { + size_t const dictContentSize = cdict ? cdict->dictContentSize : dictSize; #if ZSTD_TRACE cctx->traceCtx = (ZSTD_trace_compress_begin != NULL) ? ZSTD_trace_compress_begin(cctx) : 0; #endif @@ -4396,6 +4424,7 @@ static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx, } FORWARD_IF_ERROR( ZSTD_resetCCtx_internal(cctx, *params, pledgedSrcSize, + dictContentSize, ZSTDcrp_makeClean, zbuff) , ""); { size_t const dictID = cdict ? ZSTD_compress_insertDictionary( @@ -4410,7 +4439,7 @@ static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx, FORWARD_IF_ERROR(dictID, "ZSTD_compress_insertDictionary failed"); assert(dictID <= UINT_MAX); cctx->dictID = (U32)dictID; - cctx->dictContentSize = cdict ? cdict->dictContentSize : dictSize; + cctx->dictContentSize = dictContentSize; } return 0; } @@ -4680,9 +4709,6 @@ static size_t ZSTD_initCDict_internal( assert(!ZSTD_checkCParams(params.cParams)); cdict->matchState.cParams = params.cParams; cdict->matchState.dedicatedDictSearch = params.enableDedicatedDictSearch; - if (cdict->matchState.dedicatedDictSearch && dictSize > ZSTD_CHUNKSIZE_MAX) { - cdict->matchState.dedicatedDictSearch = 0; - } if ((dictLoadMethod == ZSTD_dlm_byRef) || (!dictBuffer) || (!dictSize)) { cdict->dictContent = dictBuffer; } else { diff --git a/lib/compress/zstd_compress_internal.h b/lib/compress/zstd_compress_internal.h index 3e6c576d1..c0b017948 100644 --- a/lib/compress/zstd_compress_internal.h +++ b/lib/compress/zstd_compress_internal.h @@ -872,6 +872,13 @@ MEM_STATIC void ZSTD_window_clear(ZSTD_window_t* window) window->dictLimit = end; } +MEM_STATIC U32 ZSTD_window_isEmpty(ZSTD_window_t const window) +{ + return window.dictLimit == 1 && + window.lowLimit == 1 && + (window.nextSrc - window.base) == 1; +} + /** * ZSTD_window_hasExtDict(): * Returns non-zero if the window has a non-empty extDict.