1/*
2 * Copyright (c) 2000-2008 Marc Alexander Lehmann <[email protected]>
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 */
76size_t
77lzf_compress (const void *const in_data, size_t in_len,
78 void *out_data, size_t 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 */
95size_t
96lzf_decompress (const void *const in_data, size_t in_len,
97 void *out_data, size_t out_len);
98
99#endif
100
101