165 lines
6.2 KiB
C
165 lines
6.2 KiB
C
/****************************************************************************
|
|
* include/lzf.h
|
|
* http://liblzf.plan9.de/
|
|
*
|
|
* Copyright (c) 2000-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
|
|
* This algorithm is believed to be patent-free.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
*
|
|
* 2. 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 AUTHOR ``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 AUTHOR 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.
|
|
*
|
|
****************************************************************************/
|
|
|
|
#ifndef __INCLUDE_LZF_H
|
|
#define __INCLUDE_LZF_H
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <sys/types.h>
|
|
#include <stdint.h>
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
#ifdef CONFIG_LIBC_LZF
|
|
|
|
#define LZF_VERSION 0x0105 /* 1.5, API version */
|
|
#define HLOG CONFIG_LIBC_LZF_HLOG
|
|
|
|
#define LZF_TYPE0_HDR 0
|
|
#define LZF_TYPE1_HDR 1
|
|
|
|
#define LZF_TYPE0_HDR_SIZE 5
|
|
#define LZF_TYPE1_HDR_SIZE 7
|
|
|
|
#define LZF_MAX_HDR_SIZE 7
|
|
#define LZF_MIN_HDR_SIZE 5
|
|
|
|
/****************************************************************************
|
|
* Public Types
|
|
****************************************************************************/
|
|
|
|
/* LZF headers */
|
|
|
|
struct lzf_header_s /* Common data header */
|
|
{
|
|
uint8_t lzf_magic[2]; /* [0]='Z', [1]='V' */
|
|
uint8_t lzf_type; /* LZF_TYPE0_HDR or LZF_TYPE1_HDR */
|
|
};
|
|
|
|
struct lzf_type0_header_s /* Uncompressed data header */
|
|
{
|
|
uint8_t lzf_magic[2]; /* [0]='Z', [1]='V' */
|
|
uint8_t lzf_type; /* LZF_TYPE0_HDR */
|
|
uint8_t lzf_len[2]; /* Data length (big-endian) */
|
|
};
|
|
|
|
struct lzf_type1_header_s /* Compressed data header */
|
|
{
|
|
uint8_t lzf_magic[2]; /* [0]='Z', [1]='V' */
|
|
uint8_t lzf_type; /* LZF_TYPE1_HDR */
|
|
uint8_t lzf_clen[2]; /* Compressed data length (big-endian) */
|
|
uint8_t lzf_ulen[2]; /* Uncompressed data length (big-endian) */
|
|
};
|
|
|
|
/* LZF hash table */
|
|
|
|
#if LZF_USE_OFFSETS
|
|
# define LZF_HSLOT_BIAS ((const uint8_t *)in_data)
|
|
typedef unsigned int lzf_hslot_t;
|
|
#else
|
|
# define LZF_HSLOT_BIAS 0
|
|
typedef const uint8_t *lzf_hslot_t;
|
|
#endif
|
|
|
|
typedef lzf_hslot_t lzf_state_t[1 << HLOG];
|
|
|
|
/****************************************************************************
|
|
* Public Function Prototypes
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: lzf_compress
|
|
*
|
|
* Description:
|
|
* Compress in_len bytes stored at the memory block starting at
|
|
* in_data and write the result to out_data, up to a maximum length
|
|
* of out_len bytes.
|
|
*
|
|
* If the output buffer is not large enough or any error occurs return 0,
|
|
* otherwise return the number of bytes used, which might be considerably
|
|
* more than in_len (but less than 104% of the original size), so it
|
|
* makes sense to always use out_len == in_len - 1), to ensure _some_
|
|
* compression, and store the data uncompressed otherwise (with a flag, of
|
|
* course.
|
|
*
|
|
* lzf_compress might use different algorithms on different systems and
|
|
* even different runs, thus might result in different compressed strings
|
|
* depending on the phase of the moon or similar factors. However, all
|
|
* these strings are architecture-independent and will result in the
|
|
* original data when decompressed using lzf_decompress.
|
|
*
|
|
* The buffers must not be overlapping.
|
|
*
|
|
* Compressed format:
|
|
*
|
|
* 000LLLLL <L+1> ; literal, L+1=1..33 octets
|
|
* LLLooooo oooooooo ; backref L+1=1..7 octets, o+1=1..4096 offset
|
|
* 111ooooo LLLLLLLL oooooooo ; backref L+8 octets, o+1=1..4096 offset
|
|
*
|
|
****************************************************************************/
|
|
|
|
size_t lzf_compress(FAR const void *const in_data,
|
|
unsigned int in_len, FAR void *out_data,
|
|
unsigned int out_len, lzf_state_t htab,
|
|
FAR struct lzf_header_s **reshdr);
|
|
|
|
/****************************************************************************
|
|
* Name: lzf_decompress
|
|
*
|
|
* Description:
|
|
* Decompress data compressed with some version of the lzf_compress
|
|
* function and stored at location in_data and length in_len. The result
|
|
* will be stored at out_data up to a maximum of out_len characters.
|
|
*
|
|
* If the output buffer is not large enough to hold the decompressed
|
|
* data, a 0 is returned and errno is set to E2BIG. Otherwise the number
|
|
* of decompressed bytes (i.e. the original length of the data) is
|
|
* returned.
|
|
*
|
|
* If an error in the compressed data is detected, a zero is returned and
|
|
* errno is set to EINVAL.
|
|
*
|
|
* This function is very fast, about as fast as a copying loop.
|
|
*
|
|
****************************************************************************/
|
|
|
|
unsigned int lzf_decompress(FAR const void *const in_data,
|
|
unsigned int in_len, FAR void *out_data,
|
|
unsigned int out_len);
|
|
|
|
#endif /* CONFIG_LIBC_LZF */
|
|
#endif /* __INCLUDE_LZF_H */
|