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 #include "lzfP.h" 41 42 /*********************************************************************** 43 ** 44 ** lzf -- an extremely fast/free compression/decompression-method 45 ** http://liblzf.plan9.de/ 46 ** 47 ** This algorithm is believed to be patent-free. 48 ** 49 ***********************************************************************/ 50 51 #define LZF_VERSION 0x0105 /* 1.5, API version */ 52 53 /* 54 * Compress in_len bytes stored at the memory block starting at 55 * in_data and write the result to out_data, up to a maximum length 56 * of out_len bytes. 57 * 58 * If the output buffer is not large enough or any error occurs return 0, 59 * otherwise return the number of bytes used, which might be considerably 60 * more than in_len (but less than 104% of the original size), so it 61 * makes sense to always use out_len == in_len - 1), to ensure _some_ 62 * compression, and store the data uncompressed otherwise (with a flag, of 63 * course. 64 * 65 * lzf_compress might use different algorithms on different systems and 66 * even different runs, thus might result in different compressed strings 67 * depending on the phase of the moon or similar factors. However, all 68 * these strings are architecture-independent and will result in the 69 * original data when decompressed using lzf_decompress. 70 * 71 * The buffers must not be overlapping. 72 * 73 * If the option LZF_STATE_ARG is enabled, an extra argument must be 74 * supplied which is not reflected in this header file. Refer to lzfP.h 75 * and lzf_c.c. 76 * 77 */ 78 unsigned int 79 lzf_compress (const void *const in_data, unsigned int in_len, 80 void *out_data, unsigned int out_len, 81 LZF_STATE htab); 82 83 /* 84 * Decompress data compressed with some version of the lzf_compress 85 * function and stored at location in_data and length in_len. The result 86 * will be stored at out_data up to a maximum of out_len characters. 87 * 88 * If the output buffer is not large enough to hold the decompressed 89 * data, a 0 is returned and errno is set to E2BIG. Otherwise the number 90 * of decompressed bytes (i.e. the original length of the data) is 91 * returned. 92 * 93 * If an error in the compressed data is detected, a zero is returned and 94 * errno is set to EINVAL. 95 * 96 * This function is very fast, about as fast as a copying loop. 97 */ 98 unsigned int 99 lzf_decompress (const void *const in_data, unsigned int in_len, 100 void *out_data, unsigned int out_len); 101 102 #endif 103 104