1 /* 2 * Copyright (c) 2000-2007 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 LZFP_h 38 #define LZFP_h 39 40 #define STANDALONE 1 /* at the moment, this is ok. */ 41 42 #ifndef STANDALONE 43 # include "lzf.h" 44 #endif 45 46 /* 47 * Size of hashtable is (1 << HLOG) * sizeof (char *) 48 * decompression is independent of the hash table size 49 * the difference between 15 and 14 is very small 50 * for small blocks (and 14 is usually a bit faster). 51 * For a low-memory/faster configuration, use HLOG == 13; 52 * For best compression, use 15 or 16 (or more, up to 23). 53 */ 54 #ifndef HLOG 55 # define HLOG 16 56 #endif 57 58 /* 59 * Sacrifice very little compression quality in favour of compression speed. 60 * This gives almost the same compression as the default code, and is 61 * (very roughly) 15% faster. This is the preferred mode of operation. 62 */ 63 #ifndef VERY_FAST 64 # define VERY_FAST 1 65 #endif 66 67 /* 68 * Sacrifice some more compression quality in favour of compression speed. 69 * (roughly 1-2% worse compression for large blocks and 70 * 9-10% for small, redundant, blocks and >>20% better speed in both cases) 71 * In short: when in need for speed, enable this for binary data, 72 * possibly disable this for text data. 73 */ 74 #ifndef ULTRA_FAST 75 # define ULTRA_FAST 0 76 #endif 77 78 /* 79 * Unconditionally aligning does not cost very much, so do it if unsure 80 */ 81 #ifndef STRICT_ALIGN 82 # define STRICT_ALIGN !(defined(__i386) || defined (__amd64)) 83 #endif 84 85 /* 86 * You may choose to pre-set the hash table (might be faster on some 87 * modern cpus and large (>>64k) blocks, and also makes compression 88 * deterministic/repeatable when the configuration otherwise is the same). 89 */ 90 #ifndef INIT_HTAB 91 # define INIT_HTAB 0 92 #endif 93 94 /* 95 * Avoid assigning values to errno variable? for some embedding purposes 96 * (linux kernel for example), this is neccessary. NOTE: this breaks 97 * the documentation in lzf.h. 98 */ 99 #ifndef AVOID_ERRNO 100 # define AVOID_ERRNO 0 101 #endif 102 103 /* 104 * Wether to pass the LZF_STATE variable as argument, or allocate it 105 * on the stack. For small-stack environments, define this to 1. 106 * NOTE: this breaks the prototype in lzf.h. 107 */ 108 #ifndef LZF_STATE_ARG 109 # define LZF_STATE_ARG 0 110 #endif 111 112 /* 113 * Wether to add extra checks for input validity in lzf_decompress 114 * and return EINVAL if the input stream has been corrupted. This 115 * only shields against overflowing the input buffer and will not 116 * detect most corrupted streams. 117 * This check is not normally noticable on modern hardware 118 * (<1% slowdown), but might slow down older cpus considerably. 119 */ 120 #ifndef CHECK_INPUT 121 # define CHECK_INPUT 1 122 #endif 123 124 /*****************************************************************************/ 125 /* nothing should be changed below */ 126 127 typedef unsigned char u8; 128 129 typedef const u8 *LZF_STATE[1 << (HLOG)]; 130 131 #if !STRICT_ALIGN 132 /* for unaligned accesses we need a 16 bit datatype. */ 133 # include <limits.h> 134 # if USHRT_MAX == 65535 135 typedef unsigned short u16; 136 # elif UINT_MAX == 65535 137 typedef unsigned int u16; 138 # else 139 # undef STRICT_ALIGN 140 # define STRICT_ALIGN 1 141 # endif 142 #endif 143 144 #if ULTRA_FAST 145 # if defined(VERY_FAST) 146 # undef VERY_FAST 147 # endif 148 #endif 149 150 #if INIT_HTAB 151 # ifdef __cplusplus 152 # include <cstring> 153 # else 154 # include <string.h> 155 # endif 156 #endif 157 158 #endif 159 160