[redis.git] / lzf.h

/*
 * Copyright (c) 2000-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
 * 
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, 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 MER-
 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
 * CIAL, 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 OTH-
 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License ("GPL") version 2 or any later version,
 * in which case the provisions of the GPL are applicable instead of
 * the above. If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the BSD license, indicate your decision
 * by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL. If you do not delete the
 * provisions above, a recipient may use your version of this file under
 * either the BSD or the GPL.
 */

#ifndef LZF_H
#define LZF_H

/***********************************************************************
**
**	lzf -- an extremely fast/free compression/decompression-method
**	http://liblzf.plan9.de/
**
**	This algorithm is believed to be patent-free.
**
***********************************************************************/

#define LZF_VERSION 0x0105 /* 1.5, API version */

/*
 * 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.
 *
 * If the option LZF_STATE_ARG is enabled, an extra argument must be
 * supplied which is not reflected in this header file. Refer to lzfP.h
 * and lzf_c.c.
 *
 */
unsigned int 
lzf_compress (const void *const in_data,  unsigned int in_len,
              void             *out_data, unsigned int out_len);

/*
 * 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 (const void *const in_data,  unsigned int in_len,
                void             *out_data, unsigned int out_len);

#endif
Commit	Line	Data
d0751937	1	/*
	2	* Copyright (c) 2000-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
	3	*
	4	* Redistribution and use in source and binary forms, with or without modifica-
	5	* tion, are permitted provided that the following conditions are met:
	6	*
	7	* 1. Redistributions of source code must retain the above copyright notice,
	8	* this list of conditions and the following disclaimer.
	9	*
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	*
	14	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
	15	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
	16	* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
	17	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
	18	* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	19	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
	20	* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
	21	* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
	22	* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
	23	* OF THE POSSIBILITY OF SUCH DAMAGE.
	24	*
	25	* Alternatively, the contents of this file may be used under the terms of
	26	* the GNU General Public License ("GPL") version 2 or any later version,
	27	* in which case the provisions of the GPL are applicable instead of
	28	* the above. If you wish to allow the use of your version of this file
	29	* only under the terms of the GPL and not to allow others to use your
	30	* version of this file under the BSD license, indicate your decision
	31	* by deleting the provisions above and replace them with the notice
	32	* and other provisions required by the GPL. If you do not delete the
	33	* provisions above, a recipient may use your version of this file under
	34	* either the BSD or the GPL.
	35	*/
	36
	37	#ifndef LZF_H
	38	#define LZF_H
	39
	40	/***********************************************************************
	41	**
	42	** lzf -- an extremely fast/free compression/decompression-method
	43	** http://liblzf.plan9.de/
	44	**
	45	** This algorithm is believed to be patent-free.
	46	**
	47	***********************************************************************/
	48
	49	#define LZF_VERSION 0x0105 /* 1.5, API version */
	50
	51	/*
	52	* Compress in_len bytes stored at the memory block starting at
	53	* in_data and write the result to out_data, up to a maximum length
	54	* of out_len bytes.
	55	*
	56	* If the output buffer is not large enough or any error occurs return 0,
	57	* otherwise return the number of bytes used, which might be considerably
	58	* more than in_len (but less than 104% of the original size), so it
	59	* makes sense to always use out_len == in_len - 1), to ensure _some_
	60	* compression, and store the data uncompressed otherwise (with a flag, of
	61	* course.
	62	*
	63	* lzf_compress might use different algorithms on different systems and
	64	* even different runs, thus might result in different compressed strings
65	* depending on the phase of the moon or similar factors. However, all
66	* these strings are architecture-independent and will result in the
67	* original data when decompressed using lzf_decompress.
68	*
69	* The buffers must not be overlapping.
70	*
71	* If the option LZF_STATE_ARG is enabled, an extra argument must be
72	* supplied which is not reflected in this header file. Refer to lzfP.h
73	* and lzf_c.c.
74	*
75	*/
76	unsigned int
77	lzf_compress (const void *const in_data, unsigned int in_len,
78	void *out_data, unsigned int out_len);
79
80	/*
81	* Decompress data compressed with some version of the lzf_compress
82	* function and stored at location in_data and length in_len. The result
83	* will be stored at out_data up to a maximum of out_len characters.
84	*
85	* If the output buffer is not large enough to hold the decompressed
86	* data, a 0 is returned and errno is set to E2BIG. Otherwise the number
87	* of decompressed bytes (i.e. the original length of the data) is
88	* returned.
89	*
90	* If an error in the compressed data is detected, a zero is returned and
91	* errno is set to EINVAL.
92	*
93	* This function is very fast, about as fast as a copying loop.
94	*/
95	unsigned int
96	lzf_decompress (const void *const in_data, unsigned int in_len,
97	void *out_data, unsigned int out_len);
98
99	#endif
100