linux/lib/lz4/lz4hc_compress.c

/*
 * LZ4 HC - High Compression Mode of LZ4
 * Copyright (C) 2011-2015, Yann Collet.
 *
 * BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php)
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *	* Redistributions of source code must retain the above copyright
 *	  notice, this list of conditions and the following disclaimer.
 *	* Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * You can contact the author at :
 *	- LZ4 homepage : http://www.lz4.org
 *	- LZ4 source repository : https://github.com/lz4/lz4
 *
 *	Changed for kernel usage by:
 *	Sven Schmidt <[email protected]>
 */

/*-************************************
 *	Dependencies
 **************************************/
#include <linux/lz4.h>
#include "lz4defs.h"
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h> /* memset */

/* *************************************
 *	Local Constants and types
 ***************************************/

#define OPTIMAL_ML …

#define HASH_FUNCTION(i) …
#define DELTANEXTU16(p) …

static U32 LZ4HC_hashPtr(const void *ptr)
{ … }

/**************************************
 *	HC Compression
 **************************************/
static void LZ4HC_init(LZ4HC_CCtx_internal *hc4, const BYTE *start)
{ … }

/* Update chains up to ip (excluded) */
static FORCE_INLINE void LZ4HC_Insert(LZ4HC_CCtx_internal *hc4,
	const BYTE *ip)
{ … }

static FORCE_INLINE int LZ4HC_InsertAndFindBestMatch(
	LZ4HC_CCtx_internal *hc4, /* Index table will be updated */
	const BYTE *ip,
	const BYTE * const iLimit,
	const BYTE **matchpos,
	const int maxNbAttempts)
{ … }

static FORCE_INLINE int LZ4HC_InsertAndGetWiderMatch(
	LZ4HC_CCtx_internal *hc4,
	const BYTE * const ip,
	const BYTE * const iLowLimit,
	const BYTE * const iHighLimit,
	int longest,
	const BYTE **matchpos,
	const BYTE **startpos,
	const int maxNbAttempts)
{ … }

static FORCE_INLINE int LZ4HC_encodeSequence(
	const BYTE **ip,
	BYTE **op,
	const BYTE **anchor,
	int matchLength,
	const BYTE * const match,
	limitedOutput_directive limitedOutputBuffer,
	BYTE *oend)
{ … }

static int LZ4HC_compress_generic(
	LZ4HC_CCtx_internal *const ctx,
	const char * const source,
	char * const dest,
	int const inputSize,
	int const maxOutputSize,
	int compressionLevel,
	limitedOutput_directive limit
	)
{ … }

static int LZ4_compress_HC_extStateHC(
	void *state,
	const char *src,
	char *dst,
	int srcSize,
	int maxDstSize,
	int compressionLevel)
{ … }

int LZ4_compress_HC(const char *src, char *dst, int srcSize,
	int maxDstSize, int compressionLevel, void *wrkmem)
{ … }
EXPORT_SYMBOL(…);

/**************************************
 *	Streaming Functions
 **************************************/
void LZ4_resetStreamHC(LZ4_streamHC_t *LZ4_streamHCPtr, int compressionLevel)
{ … }

int LZ4_loadDictHC(LZ4_streamHC_t *LZ4_streamHCPtr,
	const char *dictionary,
	int dictSize)
{ … }
EXPORT_SYMBOL(…);

/* compression */

static void LZ4HC_setExternalDict(
	LZ4HC_CCtx_internal *ctxPtr,
	const BYTE *newBlock)
{ … }

static int LZ4_compressHC_continue_generic(
	LZ4_streamHC_t *LZ4_streamHCPtr,
	const char *source,
	char *dest,
	int inputSize,
	int maxOutputSize,
	limitedOutput_directive limit)
{ … }

int LZ4_compress_HC_continue(
	LZ4_streamHC_t *LZ4_streamHCPtr,
	const char *source,
	char *dest,
	int inputSize,
	int maxOutputSize)
{ … }
EXPORT_SYMBOL(…);

/* dictionary saving */

int LZ4_saveDictHC(
	LZ4_streamHC_t *LZ4_streamHCPtr,
	char *safeBuffer,
	int dictSize)
{ … }
EXPORT_SYMBOL(…);

MODULE_LICENSE(…) …;
MODULE_DESCRIPTION(…) …;