--- /dev/null
+/*
+ * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+/* zstd_ddict.c :
+ * concentrates all logic that needs to know the internals of ZSTD_DDict object */
+
+/*-*******************************************************
+* Dependencies
+*********************************************************/
+#include <string.h> /* memcpy, memmove, memset */
+#include "cpu.h" /* bmi2 */
+#include "mem.h" /* low level memory routines */
+#define FSE_STATIC_LINKING_ONLY
+#include "fse.h"
+#define HUF_STATIC_LINKING_ONLY
+#include "huf.h"
+#include "zstd_decompress_internal.h"
+#include "zstd_ddict.h"
+
+#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
+# include "../legacy/zstd_legacy.h"
+#endif
+
+
+
+/*-*******************************************************
+* Types
+*********************************************************/
+struct ZSTD_DDict_s {
+ void* dictBuffer;
+ const void* dictContent;
+ size_t dictSize;
+ ZSTD_entropyDTables_t entropy;
+ U32 dictID;
+ U32 entropyPresent;
+ ZSTD_customMem cMem;
+}; /* typedef'd to ZSTD_DDict within "zstd.h" */
+
+const void* ZSTD_DDict_dictContent(const ZSTD_DDict* ddict)
+{
+ assert(ddict != NULL);
+ return ddict->dictContent;
+}
+
+size_t ZSTD_DDict_dictSize(const ZSTD_DDict* ddict)
+{
+ assert(ddict != NULL);
+ return ddict->dictSize;
+}
+
+void ZSTD_copyDDictParameters(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict)
+{
+ DEBUGLOG(4, "ZSTD_copyDDictParameters");
+ assert(dctx != NULL);
+ assert(ddict != NULL);
+ dctx->dictID = ddict->dictID;
+ dctx->prefixStart = ddict->dictContent;
+ dctx->virtualStart = ddict->dictContent;
+ dctx->dictEnd = (const BYTE*)ddict->dictContent + ddict->dictSize;
+ dctx->previousDstEnd = dctx->dictEnd;
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+ dctx->dictContentBeginForFuzzing = dctx->prefixStart;
+ dctx->dictContentEndForFuzzing = dctx->previousDstEnd;
+#endif
+ if (ddict->entropyPresent) {
+ dctx->litEntropy = 1;
+ dctx->fseEntropy = 1;
+ dctx->LLTptr = ddict->entropy.LLTable;
+ dctx->MLTptr = ddict->entropy.MLTable;
+ dctx->OFTptr = ddict->entropy.OFTable;
+ dctx->HUFptr = ddict->entropy.hufTable;
+ dctx->entropy.rep[0] = ddict->entropy.rep[0];
+ dctx->entropy.rep[1] = ddict->entropy.rep[1];
+ dctx->entropy.rep[2] = ddict->entropy.rep[2];
+ } else {
+ dctx->litEntropy = 0;
+ dctx->fseEntropy = 0;
+ }
+}
+
+
+static size_t
+ZSTD_loadEntropy_intoDDict(ZSTD_DDict* ddict,
+ ZSTD_dictContentType_e dictContentType)
+{
+ ddict->dictID = 0;
+ ddict->entropyPresent = 0;
+ if (dictContentType == ZSTD_dct_rawContent) return 0;
+
+ if (ddict->dictSize < 8) {
+ if (dictContentType == ZSTD_dct_fullDict)
+ return ERROR(dictionary_corrupted); /* only accept specified dictionaries */
+ return 0; /* pure content mode */
+ }
+ { U32 const magic = MEM_readLE32(ddict->dictContent);
+ if (magic != ZSTD_MAGIC_DICTIONARY) {
+ if (dictContentType == ZSTD_dct_fullDict)
+ return ERROR(dictionary_corrupted); /* only accept specified dictionaries */
+ return 0; /* pure content mode */
+ }
+ }
+ ddict->dictID = MEM_readLE32((const char*)ddict->dictContent + ZSTD_FRAMEIDSIZE);
+
+ /* load entropy tables */
+ RETURN_ERROR_IF(ZSTD_isError(ZSTD_loadDEntropy(
+ &ddict->entropy, ddict->dictContent, ddict->dictSize)),
+ dictionary_corrupted, "");
+ ddict->entropyPresent = 1;
+ return 0;
+}
+
+
+static size_t ZSTD_initDDict_internal(ZSTD_DDict* ddict,
+ const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType)
+{
+ if ((dictLoadMethod == ZSTD_dlm_byRef) || (!dict) || (!dictSize)) {
+ ddict->dictBuffer = NULL;
+ ddict->dictContent = dict;
+ if (!dict) dictSize = 0;
+ } else {
+ void* const internalBuffer = ZSTD_malloc(dictSize, ddict->cMem);
+ ddict->dictBuffer = internalBuffer;
+ ddict->dictContent = internalBuffer;
+ if (!internalBuffer) return ERROR(memory_allocation);
+ memcpy(internalBuffer, dict, dictSize);
+ }
+ ddict->dictSize = dictSize;
+ ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */
+
+ /* parse dictionary content */
+ FORWARD_IF_ERROR( ZSTD_loadEntropy_intoDDict(ddict, dictContentType) , "");
+
+ return 0;
+}
+
+ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType,
+ ZSTD_customMem customMem)
+{
+ if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
+
+ { ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
+ if (ddict == NULL) return NULL;
+ ddict->cMem = customMem;
+ { size_t const initResult = ZSTD_initDDict_internal(ddict,
+ dict, dictSize,
+ dictLoadMethod, dictContentType);
+ if (ZSTD_isError(initResult)) {
+ ZSTD_freeDDict(ddict);
+ return NULL;
+ } }
+ return ddict;
+ }
+}
+
+/*! ZSTD_createDDict() :
+* Create a digested dictionary, to start decompression without startup delay.
+* `dict` content is copied inside DDict.
+* Consequently, `dict` can be released after `ZSTD_DDict` creation */
+ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
+{
+ ZSTD_customMem const allocator = { NULL, NULL, NULL };
+ return ZSTD_createDDict_advanced(dict, dictSize, ZSTD_dlm_byCopy, ZSTD_dct_auto, allocator);
+}
+
+/*! ZSTD_createDDict_byReference() :
+ * Create a digested dictionary, to start decompression without startup delay.
+ * Dictionary content is simply referenced, it will be accessed during decompression.
+ * Warning : dictBuffer must outlive DDict (DDict must be freed before dictBuffer) */
+ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize)
+{
+ ZSTD_customMem const allocator = { NULL, NULL, NULL };
+ return ZSTD_createDDict_advanced(dictBuffer, dictSize, ZSTD_dlm_byRef, ZSTD_dct_auto, allocator);
+}
+
+
+const ZSTD_DDict* ZSTD_initStaticDDict(
+ void* sBuffer, size_t sBufferSize,
+ const void* dict, size_t dictSize,
+ ZSTD_dictLoadMethod_e dictLoadMethod,
+ ZSTD_dictContentType_e dictContentType)
+{
+ size_t const neededSpace = sizeof(ZSTD_DDict)
+ + (dictLoadMethod == ZSTD_dlm_byRef ? 0 : dictSize);
+ ZSTD_DDict* const ddict = (ZSTD_DDict*)sBuffer;
+ assert(sBuffer != NULL);
+ assert(dict != NULL);
+ if ((size_t)sBuffer & 7) return NULL; /* 8-aligned */
+ if (sBufferSize < neededSpace) return NULL;
+ if (dictLoadMethod == ZSTD_dlm_byCopy) {
+ memcpy(ddict+1, dict, dictSize); /* local copy */
+ dict = ddict+1;
+ }
+ if (ZSTD_isError( ZSTD_initDDict_internal(ddict,
+ dict, dictSize,
+ ZSTD_dlm_byRef, dictContentType) ))
+ return NULL;
+ return ddict;
+}
+
+
+size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
+{
+ if (ddict==NULL) return 0; /* support free on NULL */
+ { ZSTD_customMem const cMem = ddict->cMem;
+ ZSTD_free(ddict->dictBuffer, cMem);
+ ZSTD_free(ddict, cMem);
+ return 0;
+ }
+}
+
+/*! ZSTD_estimateDDictSize() :
+ * Estimate amount of memory that will be needed to create a dictionary for decompression.
+ * Note : dictionary created by reference using ZSTD_dlm_byRef are smaller */
+size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod)
+{
+ return sizeof(ZSTD_DDict) + (dictLoadMethod == ZSTD_dlm_byRef ? 0 : dictSize);
+}
+
+size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
+{
+ if (ddict==NULL) return 0; /* support sizeof on NULL */
+ return sizeof(*ddict) + (ddict->dictBuffer ? ddict->dictSize : 0) ;
+}
+
+/*! ZSTD_getDictID_fromDDict() :
+ * Provides the dictID of the dictionary loaded into `ddict`.
+ * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
+ * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */
+unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict)
+{
+ if (ddict==NULL) return 0;
+ return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize);
+}
projects / reactos.git / blobdiff