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![Sven Schmidt](/assets/img/avatar_default.png)
Remove the functions introduced as wrappers for providing backwards compatibility to the prior LZ4 version. They're not needed anymore since there's no callers left. Link: http://lkml.kernel.org/r/1486321748-19085-6-git-send-email-4sschmid@informatik.uni-hamburg.de Signed-off-by: Sven Schmidt <4sschmid@informatik.uni-hamburg.de> Cc: Bongkyu Kim <bongkyu.kim@lge.com> Cc: Rui Salvaterra <rsalvaterra@gmail.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: David S. Miller <davem@davemloft.net> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
940 lines
23 KiB
C
940 lines
23 KiB
C
/*
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* LZ4 - Fast LZ compression algorithm
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* Copyright (C) 2011 - 2016, Yann Collet.
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* BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php)
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are
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* met:
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above
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* copyright notice, this list of conditions and the following disclaimer
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* in the documentation and/or other materials provided with the
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* distribution.
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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* You can contact the author at :
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* - LZ4 homepage : http://www.lz4.org
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* - LZ4 source repository : https://github.com/lz4/lz4
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*
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* Changed for kernel usage by:
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* Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
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*/
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/*-************************************
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* Dependencies
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**************************************/
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#include <linux/lz4.h>
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#include "lz4defs.h"
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <asm/unaligned.h>
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static const int LZ4_minLength = (MFLIMIT + 1);
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static const int LZ4_64Klimit = ((64 * KB) + (MFLIMIT - 1));
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/*-******************************
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* Compression functions
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********************************/
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static FORCE_INLINE U32 LZ4_hash4(
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U32 sequence,
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tableType_t const tableType)
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{
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if (tableType == byU16)
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return ((sequence * 2654435761U)
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>> ((MINMATCH * 8) - (LZ4_HASHLOG + 1)));
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else
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return ((sequence * 2654435761U)
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>> ((MINMATCH * 8) - LZ4_HASHLOG));
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}
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static FORCE_INLINE U32 LZ4_hash5(
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U64 sequence,
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tableType_t const tableType)
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{
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const U32 hashLog = (tableType == byU16)
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? LZ4_HASHLOG + 1
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: LZ4_HASHLOG;
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#if LZ4_LITTLE_ENDIAN
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static const U64 prime5bytes = 889523592379ULL;
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return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
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#else
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static const U64 prime8bytes = 11400714785074694791ULL;
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return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
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#endif
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}
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static FORCE_INLINE U32 LZ4_hashPosition(
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const void *p,
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tableType_t const tableType)
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{
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#if LZ4_ARCH64
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if (tableType == byU32)
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return LZ4_hash5(LZ4_read_ARCH(p), tableType);
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#endif
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return LZ4_hash4(LZ4_read32(p), tableType);
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}
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static void LZ4_putPositionOnHash(
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const BYTE *p,
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U32 h,
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void *tableBase,
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tableType_t const tableType,
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const BYTE *srcBase)
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{
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switch (tableType) {
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case byPtr:
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{
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const BYTE **hashTable = (const BYTE **)tableBase;
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hashTable[h] = p;
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return;
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}
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case byU32:
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{
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U32 *hashTable = (U32 *) tableBase;
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hashTable[h] = (U32)(p - srcBase);
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return;
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}
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case byU16:
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{
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U16 *hashTable = (U16 *) tableBase;
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hashTable[h] = (U16)(p - srcBase);
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return;
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}
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}
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}
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static FORCE_INLINE void LZ4_putPosition(
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const BYTE *p,
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void *tableBase,
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tableType_t tableType,
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const BYTE *srcBase)
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{
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U32 const h = LZ4_hashPosition(p, tableType);
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LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
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}
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static const BYTE *LZ4_getPositionOnHash(
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U32 h,
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void *tableBase,
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tableType_t tableType,
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const BYTE *srcBase)
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{
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if (tableType == byPtr) {
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const BYTE **hashTable = (const BYTE **) tableBase;
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return hashTable[h];
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}
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if (tableType == byU32) {
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const U32 * const hashTable = (U32 *) tableBase;
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return hashTable[h] + srcBase;
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}
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{
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/* default, to ensure a return */
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const U16 * const hashTable = (U16 *) tableBase;
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return hashTable[h] + srcBase;
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}
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}
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static FORCE_INLINE const BYTE *LZ4_getPosition(
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const BYTE *p,
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void *tableBase,
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tableType_t tableType,
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const BYTE *srcBase)
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{
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U32 const h = LZ4_hashPosition(p, tableType);
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return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
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}
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/*
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* LZ4_compress_generic() :
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* inlined, to ensure branches are decided at compilation time
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*/
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static FORCE_INLINE int LZ4_compress_generic(
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LZ4_stream_t_internal * const dictPtr,
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const char * const source,
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char * const dest,
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const int inputSize,
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const int maxOutputSize,
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const limitedOutput_directive outputLimited,
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const tableType_t tableType,
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const dict_directive dict,
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const dictIssue_directive dictIssue,
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const U32 acceleration)
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{
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const BYTE *ip = (const BYTE *) source;
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const BYTE *base;
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const BYTE *lowLimit;
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const BYTE * const lowRefLimit = ip - dictPtr->dictSize;
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const BYTE * const dictionary = dictPtr->dictionary;
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const BYTE * const dictEnd = dictionary + dictPtr->dictSize;
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const size_t dictDelta = dictEnd - (const BYTE *)source;
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const BYTE *anchor = (const BYTE *) source;
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const BYTE * const iend = ip + inputSize;
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const BYTE * const mflimit = iend - MFLIMIT;
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const BYTE * const matchlimit = iend - LASTLITERALS;
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BYTE *op = (BYTE *) dest;
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BYTE * const olimit = op + maxOutputSize;
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U32 forwardH;
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size_t refDelta = 0;
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/* Init conditions */
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if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) {
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/* Unsupported inputSize, too large (or negative) */
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return 0;
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}
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switch (dict) {
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case noDict:
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default:
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base = (const BYTE *)source;
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lowLimit = (const BYTE *)source;
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break;
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case withPrefix64k:
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base = (const BYTE *)source - dictPtr->currentOffset;
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lowLimit = (const BYTE *)source - dictPtr->dictSize;
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break;
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case usingExtDict:
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base = (const BYTE *)source - dictPtr->currentOffset;
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lowLimit = (const BYTE *)source;
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break;
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}
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if ((tableType == byU16)
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&& (inputSize >= LZ4_64Klimit)) {
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/* Size too large (not within 64K limit) */
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return 0;
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}
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if (inputSize < LZ4_minLength) {
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/* Input too small, no compression (all literals) */
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goto _last_literals;
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}
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/* First Byte */
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LZ4_putPosition(ip, dictPtr->hashTable, tableType, base);
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ip++;
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forwardH = LZ4_hashPosition(ip, tableType);
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/* Main Loop */
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for ( ; ; ) {
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const BYTE *match;
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BYTE *token;
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/* Find a match */
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{
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const BYTE *forwardIp = ip;
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unsigned int step = 1;
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unsigned int searchMatchNb = acceleration << LZ4_SKIPTRIGGER;
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do {
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U32 const h = forwardH;
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ip = forwardIp;
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forwardIp += step;
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step = (searchMatchNb++ >> LZ4_SKIPTRIGGER);
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if (unlikely(forwardIp > mflimit))
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goto _last_literals;
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match = LZ4_getPositionOnHash(h,
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dictPtr->hashTable,
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tableType, base);
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if (dict == usingExtDict) {
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if (match < (const BYTE *)source) {
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refDelta = dictDelta;
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lowLimit = dictionary;
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} else {
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refDelta = 0;
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lowLimit = (const BYTE *)source;
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} }
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forwardH = LZ4_hashPosition(forwardIp,
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tableType);
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LZ4_putPositionOnHash(ip, h, dictPtr->hashTable,
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tableType, base);
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} while (((dictIssue == dictSmall)
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? (match < lowRefLimit)
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: 0)
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|| ((tableType == byU16)
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? 0
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: (match + MAX_DISTANCE < ip))
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|| (LZ4_read32(match + refDelta)
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!= LZ4_read32(ip)));
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}
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/* Catch up */
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while (((ip > anchor) & (match + refDelta > lowLimit))
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&& (unlikely(ip[-1] == match[refDelta - 1]))) {
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ip--;
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match--;
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}
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/* Encode Literals */
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{
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unsigned const int litLength = (unsigned int)(ip - anchor);
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token = op++;
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if ((outputLimited) &&
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/* Check output buffer overflow */
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(unlikely(op + litLength +
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(2 + 1 + LASTLITERALS) +
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(litLength / 255) > olimit)))
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return 0;
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if (litLength >= RUN_MASK) {
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int len = (int)litLength - RUN_MASK;
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*token = (RUN_MASK << ML_BITS);
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for (; len >= 255; len -= 255)
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*op++ = 255;
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*op++ = (BYTE)len;
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} else
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*token = (BYTE)(litLength << ML_BITS);
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/* Copy Literals */
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LZ4_wildCopy(op, anchor, op + litLength);
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op += litLength;
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}
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_next_match:
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/* Encode Offset */
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LZ4_writeLE16(op, (U16)(ip - match));
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op += 2;
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/* Encode MatchLength */
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{
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unsigned int matchCode;
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if ((dict == usingExtDict)
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&& (lowLimit == dictionary)) {
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const BYTE *limit;
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match += refDelta;
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limit = ip + (dictEnd - match);
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if (limit > matchlimit)
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limit = matchlimit;
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matchCode = LZ4_count(ip + MINMATCH,
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match + MINMATCH, limit);
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ip += MINMATCH + matchCode;
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if (ip == limit) {
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unsigned const int more = LZ4_count(ip,
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(const BYTE *)source,
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matchlimit);
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matchCode += more;
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ip += more;
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}
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} else {
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matchCode = LZ4_count(ip + MINMATCH,
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match + MINMATCH, matchlimit);
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ip += MINMATCH + matchCode;
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}
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if (outputLimited &&
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/* Check output buffer overflow */
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(unlikely(op +
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(1 + LASTLITERALS) +
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(matchCode >> 8) > olimit)))
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return 0;
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if (matchCode >= ML_MASK) {
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*token += ML_MASK;
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matchCode -= ML_MASK;
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LZ4_write32(op, 0xFFFFFFFF);
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while (matchCode >= 4 * 255) {
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op += 4;
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LZ4_write32(op, 0xFFFFFFFF);
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matchCode -= 4 * 255;
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}
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op += matchCode / 255;
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*op++ = (BYTE)(matchCode % 255);
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} else
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*token += (BYTE)(matchCode);
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}
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anchor = ip;
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/* Test end of chunk */
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if (ip > mflimit)
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break;
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/* Fill table */
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LZ4_putPosition(ip - 2, dictPtr->hashTable, tableType, base);
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/* Test next position */
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match = LZ4_getPosition(ip, dictPtr->hashTable,
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tableType, base);
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if (dict == usingExtDict) {
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if (match < (const BYTE *)source) {
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refDelta = dictDelta;
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lowLimit = dictionary;
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} else {
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refDelta = 0;
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lowLimit = (const BYTE *)source;
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}
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}
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LZ4_putPosition(ip, dictPtr->hashTable, tableType, base);
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if (((dictIssue == dictSmall) ? (match >= lowRefLimit) : 1)
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&& (match + MAX_DISTANCE >= ip)
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&& (LZ4_read32(match + refDelta) == LZ4_read32(ip))) {
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token = op++;
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*token = 0;
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goto _next_match;
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}
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/* Prepare next loop */
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forwardH = LZ4_hashPosition(++ip, tableType);
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}
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_last_literals:
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/* Encode Last Literals */
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{
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size_t const lastRun = (size_t)(iend - anchor);
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if ((outputLimited) &&
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/* Check output buffer overflow */
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((op - (BYTE *)dest) + lastRun + 1 +
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((lastRun + 255 - RUN_MASK) / 255) > (U32)maxOutputSize))
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return 0;
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if (lastRun >= RUN_MASK) {
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size_t accumulator = lastRun - RUN_MASK;
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*op++ = RUN_MASK << ML_BITS;
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for (; accumulator >= 255; accumulator -= 255)
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*op++ = 255;
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*op++ = (BYTE) accumulator;
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} else {
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*op++ = (BYTE)(lastRun << ML_BITS);
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}
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memcpy(op, anchor, lastRun);
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op += lastRun;
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}
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/* End */
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return (int) (((char *)op) - dest);
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}
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static int LZ4_compress_fast_extState(
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void *state,
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const char *source,
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char *dest,
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int inputSize,
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int maxOutputSize,
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int acceleration)
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{
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LZ4_stream_t_internal *ctx = &((LZ4_stream_t *)state)->internal_donotuse;
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#if LZ4_ARCH64
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const tableType_t tableType = byU32;
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#else
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const tableType_t tableType = byPtr;
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#endif
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LZ4_resetStream((LZ4_stream_t *)state);
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if (acceleration < 1)
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acceleration = LZ4_ACCELERATION_DEFAULT;
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if (maxOutputSize >= LZ4_COMPRESSBOUND(inputSize)) {
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if (inputSize < LZ4_64Klimit)
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return LZ4_compress_generic(ctx, source,
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dest, inputSize, 0,
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noLimit, byU16, noDict,
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noDictIssue, acceleration);
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else
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return LZ4_compress_generic(ctx, source,
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dest, inputSize, 0,
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noLimit, tableType, noDict,
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noDictIssue, acceleration);
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} else {
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if (inputSize < LZ4_64Klimit)
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return LZ4_compress_generic(ctx, source,
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dest, inputSize,
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maxOutputSize, limitedOutput, byU16, noDict,
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noDictIssue, acceleration);
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else
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return LZ4_compress_generic(ctx, source,
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dest, inputSize,
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maxOutputSize, limitedOutput, tableType, noDict,
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noDictIssue, acceleration);
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}
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}
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int LZ4_compress_fast(const char *source, char *dest, int inputSize,
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int maxOutputSize, int acceleration, void *wrkmem)
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{
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return LZ4_compress_fast_extState(wrkmem, source, dest, inputSize,
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maxOutputSize, acceleration);
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}
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EXPORT_SYMBOL(LZ4_compress_fast);
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int LZ4_compress_default(const char *source, char *dest, int inputSize,
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int maxOutputSize, void *wrkmem)
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{
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return LZ4_compress_fast(source, dest, inputSize,
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maxOutputSize, LZ4_ACCELERATION_DEFAULT, wrkmem);
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}
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EXPORT_SYMBOL(LZ4_compress_default);
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/*-******************************
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* *_destSize() variant
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********************************/
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static int LZ4_compress_destSize_generic(
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LZ4_stream_t_internal * const ctx,
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const char * const src,
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char * const dst,
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int * const srcSizePtr,
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const int targetDstSize,
|
|
const tableType_t tableType)
|
|
{
|
|
const BYTE *ip = (const BYTE *) src;
|
|
const BYTE *base = (const BYTE *) src;
|
|
const BYTE *lowLimit = (const BYTE *) src;
|
|
const BYTE *anchor = ip;
|
|
const BYTE * const iend = ip + *srcSizePtr;
|
|
const BYTE * const mflimit = iend - MFLIMIT;
|
|
const BYTE * const matchlimit = iend - LASTLITERALS;
|
|
|
|
BYTE *op = (BYTE *) dst;
|
|
BYTE * const oend = op + targetDstSize;
|
|
BYTE * const oMaxLit = op + targetDstSize - 2 /* offset */
|
|
- 8 /* because 8 + MINMATCH == MFLIMIT */ - 1 /* token */;
|
|
BYTE * const oMaxMatch = op + targetDstSize
|
|
- (LASTLITERALS + 1 /* token */);
|
|
BYTE * const oMaxSeq = oMaxLit - 1 /* token */;
|
|
|
|
U32 forwardH;
|
|
|
|
/* Init conditions */
|
|
/* Impossible to store anything */
|
|
if (targetDstSize < 1)
|
|
return 0;
|
|
/* Unsupported input size, too large (or negative) */
|
|
if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE)
|
|
return 0;
|
|
/* Size too large (not within 64K limit) */
|
|
if ((tableType == byU16) && (*srcSizePtr >= LZ4_64Klimit))
|
|
return 0;
|
|
/* Input too small, no compression (all literals) */
|
|
if (*srcSizePtr < LZ4_minLength)
|
|
goto _last_literals;
|
|
|
|
/* First Byte */
|
|
*srcSizePtr = 0;
|
|
LZ4_putPosition(ip, ctx->hashTable, tableType, base);
|
|
ip++; forwardH = LZ4_hashPosition(ip, tableType);
|
|
|
|
/* Main Loop */
|
|
for ( ; ; ) {
|
|
const BYTE *match;
|
|
BYTE *token;
|
|
|
|
/* Find a match */
|
|
{
|
|
const BYTE *forwardIp = ip;
|
|
unsigned int step = 1;
|
|
unsigned int searchMatchNb = 1 << LZ4_SKIPTRIGGER;
|
|
|
|
do {
|
|
U32 h = forwardH;
|
|
|
|
ip = forwardIp;
|
|
forwardIp += step;
|
|
step = (searchMatchNb++ >> LZ4_SKIPTRIGGER);
|
|
|
|
if (unlikely(forwardIp > mflimit))
|
|
goto _last_literals;
|
|
|
|
match = LZ4_getPositionOnHash(h, ctx->hashTable,
|
|
tableType, base);
|
|
forwardH = LZ4_hashPosition(forwardIp,
|
|
tableType);
|
|
LZ4_putPositionOnHash(ip, h,
|
|
ctx->hashTable, tableType,
|
|
base);
|
|
|
|
} while (((tableType == byU16)
|
|
? 0
|
|
: (match + MAX_DISTANCE < ip))
|
|
|| (LZ4_read32(match) != LZ4_read32(ip)));
|
|
}
|
|
|
|
/* Catch up */
|
|
while ((ip > anchor)
|
|
&& (match > lowLimit)
|
|
&& (unlikely(ip[-1] == match[-1]))) {
|
|
ip--;
|
|
match--;
|
|
}
|
|
|
|
/* Encode Literal length */
|
|
{
|
|
unsigned int litLength = (unsigned int)(ip - anchor);
|
|
|
|
token = op++;
|
|
if (op + ((litLength + 240) / 255)
|
|
+ litLength > oMaxLit) {
|
|
/* Not enough space for a last match */
|
|
op--;
|
|
goto _last_literals;
|
|
}
|
|
if (litLength >= RUN_MASK) {
|
|
unsigned int len = litLength - RUN_MASK;
|
|
*token = (RUN_MASK<<ML_BITS);
|
|
for (; len >= 255; len -= 255)
|
|
*op++ = 255;
|
|
*op++ = (BYTE)len;
|
|
} else
|
|
*token = (BYTE)(litLength << ML_BITS);
|
|
|
|
/* Copy Literals */
|
|
LZ4_wildCopy(op, anchor, op + litLength);
|
|
op += litLength;
|
|
}
|
|
|
|
_next_match:
|
|
/* Encode Offset */
|
|
LZ4_writeLE16(op, (U16)(ip - match)); op += 2;
|
|
|
|
/* Encode MatchLength */
|
|
{
|
|
size_t matchLength = LZ4_count(ip + MINMATCH,
|
|
match + MINMATCH, matchlimit);
|
|
|
|
if (op + ((matchLength + 240)/255) > oMaxMatch) {
|
|
/* Match description too long : reduce it */
|
|
matchLength = (15 - 1) + (oMaxMatch - op) * 255;
|
|
}
|
|
ip += MINMATCH + matchLength;
|
|
|
|
if (matchLength >= ML_MASK) {
|
|
*token += ML_MASK;
|
|
matchLength -= ML_MASK;
|
|
while (matchLength >= 255) {
|
|
matchLength -= 255;
|
|
*op++ = 255;
|
|
}
|
|
*op++ = (BYTE)matchLength;
|
|
} else
|
|
*token += (BYTE)(matchLength);
|
|
}
|
|
|
|
anchor = ip;
|
|
|
|
/* Test end of block */
|
|
if (ip > mflimit)
|
|
break;
|
|
if (op > oMaxSeq)
|
|
break;
|
|
|
|
/* Fill table */
|
|
LZ4_putPosition(ip - 2, ctx->hashTable, tableType, base);
|
|
|
|
/* Test next position */
|
|
match = LZ4_getPosition(ip, ctx->hashTable, tableType, base);
|
|
LZ4_putPosition(ip, ctx->hashTable, tableType, base);
|
|
|
|
if ((match + MAX_DISTANCE >= ip)
|
|
&& (LZ4_read32(match) == LZ4_read32(ip))) {
|
|
token = op++; *token = 0;
|
|
goto _next_match;
|
|
}
|
|
|
|
/* Prepare next loop */
|
|
forwardH = LZ4_hashPosition(++ip, tableType);
|
|
}
|
|
|
|
_last_literals:
|
|
/* Encode Last Literals */
|
|
{
|
|
size_t lastRunSize = (size_t)(iend - anchor);
|
|
|
|
if (op + 1 /* token */
|
|
+ ((lastRunSize + 240) / 255) /* litLength */
|
|
+ lastRunSize /* literals */ > oend) {
|
|
/* adapt lastRunSize to fill 'dst' */
|
|
lastRunSize = (oend - op) - 1;
|
|
lastRunSize -= (lastRunSize + 240) / 255;
|
|
}
|
|
ip = anchor + lastRunSize;
|
|
|
|
if (lastRunSize >= RUN_MASK) {
|
|
size_t accumulator = lastRunSize - RUN_MASK;
|
|
|
|
*op++ = RUN_MASK << ML_BITS;
|
|
for (; accumulator >= 255; accumulator -= 255)
|
|
*op++ = 255;
|
|
*op++ = (BYTE) accumulator;
|
|
} else {
|
|
*op++ = (BYTE)(lastRunSize<<ML_BITS);
|
|
}
|
|
memcpy(op, anchor, lastRunSize);
|
|
op += lastRunSize;
|
|
}
|
|
|
|
/* End */
|
|
*srcSizePtr = (int) (((const char *)ip) - src);
|
|
return (int) (((char *)op) - dst);
|
|
}
|
|
|
|
static int LZ4_compress_destSize_extState(
|
|
LZ4_stream_t *state,
|
|
const char *src,
|
|
char *dst,
|
|
int *srcSizePtr,
|
|
int targetDstSize)
|
|
{
|
|
#if LZ4_ARCH64
|
|
const tableType_t tableType = byU32;
|
|
#else
|
|
const tableType_t tableType = byPtr;
|
|
#endif
|
|
|
|
LZ4_resetStream(state);
|
|
|
|
if (targetDstSize >= LZ4_COMPRESSBOUND(*srcSizePtr)) {
|
|
/* compression success is guaranteed */
|
|
return LZ4_compress_fast_extState(
|
|
state, src, dst, *srcSizePtr,
|
|
targetDstSize, 1);
|
|
} else {
|
|
if (*srcSizePtr < LZ4_64Klimit)
|
|
return LZ4_compress_destSize_generic(
|
|
&state->internal_donotuse,
|
|
src, dst, srcSizePtr,
|
|
targetDstSize, byU16);
|
|
else
|
|
return LZ4_compress_destSize_generic(
|
|
&state->internal_donotuse,
|
|
src, dst, srcSizePtr,
|
|
targetDstSize, tableType);
|
|
}
|
|
}
|
|
|
|
|
|
int LZ4_compress_destSize(
|
|
const char *src,
|
|
char *dst,
|
|
int *srcSizePtr,
|
|
int targetDstSize,
|
|
void *wrkmem)
|
|
{
|
|
return LZ4_compress_destSize_extState(wrkmem, src, dst, srcSizePtr,
|
|
targetDstSize);
|
|
}
|
|
EXPORT_SYMBOL(LZ4_compress_destSize);
|
|
|
|
/*-******************************
|
|
* Streaming functions
|
|
********************************/
|
|
void LZ4_resetStream(LZ4_stream_t *LZ4_stream)
|
|
{
|
|
memset(LZ4_stream, 0, sizeof(LZ4_stream_t));
|
|
}
|
|
|
|
int LZ4_loadDict(LZ4_stream_t *LZ4_dict,
|
|
const char *dictionary, int dictSize)
|
|
{
|
|
LZ4_stream_t_internal *dict = &LZ4_dict->internal_donotuse;
|
|
const BYTE *p = (const BYTE *)dictionary;
|
|
const BYTE * const dictEnd = p + dictSize;
|
|
const BYTE *base;
|
|
|
|
if ((dict->initCheck)
|
|
|| (dict->currentOffset > 1 * GB)) {
|
|
/* Uninitialized structure, or reuse overflow */
|
|
LZ4_resetStream(LZ4_dict);
|
|
}
|
|
|
|
if (dictSize < (int)HASH_UNIT) {
|
|
dict->dictionary = NULL;
|
|
dict->dictSize = 0;
|
|
return 0;
|
|
}
|
|
|
|
if ((dictEnd - p) > 64 * KB)
|
|
p = dictEnd - 64 * KB;
|
|
dict->currentOffset += 64 * KB;
|
|
base = p - dict->currentOffset;
|
|
dict->dictionary = p;
|
|
dict->dictSize = (U32)(dictEnd - p);
|
|
dict->currentOffset += dict->dictSize;
|
|
|
|
while (p <= dictEnd - HASH_UNIT) {
|
|
LZ4_putPosition(p, dict->hashTable, byU32, base);
|
|
p += 3;
|
|
}
|
|
|
|
return dict->dictSize;
|
|
}
|
|
EXPORT_SYMBOL(LZ4_loadDict);
|
|
|
|
static void LZ4_renormDictT(LZ4_stream_t_internal *LZ4_dict,
|
|
const BYTE *src)
|
|
{
|
|
if ((LZ4_dict->currentOffset > 0x80000000) ||
|
|
((uptrval)LZ4_dict->currentOffset > (uptrval)src)) {
|
|
/* address space overflow */
|
|
/* rescale hash table */
|
|
U32 const delta = LZ4_dict->currentOffset - 64 * KB;
|
|
const BYTE *dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
|
|
int i;
|
|
|
|
for (i = 0; i < LZ4_HASH_SIZE_U32; i++) {
|
|
if (LZ4_dict->hashTable[i] < delta)
|
|
LZ4_dict->hashTable[i] = 0;
|
|
else
|
|
LZ4_dict->hashTable[i] -= delta;
|
|
}
|
|
LZ4_dict->currentOffset = 64 * KB;
|
|
if (LZ4_dict->dictSize > 64 * KB)
|
|
LZ4_dict->dictSize = 64 * KB;
|
|
LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
|
|
}
|
|
}
|
|
|
|
int LZ4_saveDict(LZ4_stream_t *LZ4_dict, char *safeBuffer, int dictSize)
|
|
{
|
|
LZ4_stream_t_internal * const dict = &LZ4_dict->internal_donotuse;
|
|
const BYTE * const previousDictEnd = dict->dictionary + dict->dictSize;
|
|
|
|
if ((U32)dictSize > 64 * KB) {
|
|
/* useless to define a dictionary > 64 * KB */
|
|
dictSize = 64 * KB;
|
|
}
|
|
if ((U32)dictSize > dict->dictSize)
|
|
dictSize = dict->dictSize;
|
|
|
|
memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
|
|
|
|
dict->dictionary = (const BYTE *)safeBuffer;
|
|
dict->dictSize = (U32)dictSize;
|
|
|
|
return dictSize;
|
|
}
|
|
EXPORT_SYMBOL(LZ4_saveDict);
|
|
|
|
int LZ4_compress_fast_continue(LZ4_stream_t *LZ4_stream, const char *source,
|
|
char *dest, int inputSize, int maxOutputSize, int acceleration)
|
|
{
|
|
LZ4_stream_t_internal *streamPtr = &LZ4_stream->internal_donotuse;
|
|
const BYTE * const dictEnd = streamPtr->dictionary
|
|
+ streamPtr->dictSize;
|
|
|
|
const BYTE *smallest = (const BYTE *) source;
|
|
|
|
if (streamPtr->initCheck) {
|
|
/* Uninitialized structure detected */
|
|
return 0;
|
|
}
|
|
|
|
if ((streamPtr->dictSize > 0) && (smallest > dictEnd))
|
|
smallest = dictEnd;
|
|
|
|
LZ4_renormDictT(streamPtr, smallest);
|
|
|
|
if (acceleration < 1)
|
|
acceleration = LZ4_ACCELERATION_DEFAULT;
|
|
|
|
/* Check overlapping input/dictionary space */
|
|
{
|
|
const BYTE *sourceEnd = (const BYTE *) source + inputSize;
|
|
|
|
if ((sourceEnd > streamPtr->dictionary)
|
|
&& (sourceEnd < dictEnd)) {
|
|
streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
|
|
if (streamPtr->dictSize > 64 * KB)
|
|
streamPtr->dictSize = 64 * KB;
|
|
if (streamPtr->dictSize < 4)
|
|
streamPtr->dictSize = 0;
|
|
streamPtr->dictionary = dictEnd - streamPtr->dictSize;
|
|
}
|
|
}
|
|
|
|
/* prefix mode : source data follows dictionary */
|
|
if (dictEnd == (const BYTE *)source) {
|
|
int result;
|
|
|
|
if ((streamPtr->dictSize < 64 * KB) &&
|
|
(streamPtr->dictSize < streamPtr->currentOffset)) {
|
|
result = LZ4_compress_generic(
|
|
streamPtr, source, dest, inputSize,
|
|
maxOutputSize, limitedOutput, byU32,
|
|
withPrefix64k, dictSmall, acceleration);
|
|
} else {
|
|
result = LZ4_compress_generic(
|
|
streamPtr, source, dest, inputSize,
|
|
maxOutputSize, limitedOutput, byU32,
|
|
withPrefix64k, noDictIssue, acceleration);
|
|
}
|
|
streamPtr->dictSize += (U32)inputSize;
|
|
streamPtr->currentOffset += (U32)inputSize;
|
|
return result;
|
|
}
|
|
|
|
/* external dictionary mode */
|
|
{
|
|
int result;
|
|
|
|
if ((streamPtr->dictSize < 64 * KB) &&
|
|
(streamPtr->dictSize < streamPtr->currentOffset)) {
|
|
result = LZ4_compress_generic(
|
|
streamPtr, source, dest, inputSize,
|
|
maxOutputSize, limitedOutput, byU32,
|
|
usingExtDict, dictSmall, acceleration);
|
|
} else {
|
|
result = LZ4_compress_generic(
|
|
streamPtr, source, dest, inputSize,
|
|
maxOutputSize, limitedOutput, byU32,
|
|
usingExtDict, noDictIssue, acceleration);
|
|
}
|
|
streamPtr->dictionary = (const BYTE *)source;
|
|
streamPtr->dictSize = (U32)inputSize;
|
|
streamPtr->currentOffset += (U32)inputSize;
|
|
return result;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(LZ4_compress_fast_continue);
|
|
|
|
MODULE_LICENSE("Dual BSD/GPL");
|
|
MODULE_DESCRIPTION("LZ4 compressor");
|