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 #if !defined(_KERNEL) && !defined(_STANDALONE) 41 #include <sys/types.h> 42 #include <inttypes.h> 43 #endif 44 45 /* 46 * Size of hashtable is (1 << LZF_HLOG) * sizeof (char *) 47 * decompression is independent of the hash table size 48 * the difference between 15 and 14 is very small 49 * for small blocks (and 14 is usually a bit faster). 50 * For a low-memory/faster configuration, use LZF_HLOG == 13; 51 * For best compression, use 15 or 16 (or more, up to 23). 52 */ 53 #ifndef LZF_HLOG 54 # define LZF_HLOG 16 55 #endif 56 57 /* 58 * Sacrifice very little compression quality in favour of compression speed. 59 * This gives almost the same compression as the default code, and is 60 * (very roughly) 15% faster. This is the preferred mode of operation. 61 */ 62 #ifndef VERY_FAST 63 # define VERY_FAST 1 64 #endif 65 66 /* 67 * Sacrifice some more compression quality in favour of compression speed. 68 * (roughly 1-2% worse compression for large blocks and 69 * 9-10% for small, redundant, blocks and >>20% better speed in both cases) 70 * In short: when in need for speed, enable this for binary data, 71 * possibly disable this for text data. 72 */ 73 #ifndef ULTRA_FAST 74 # define ULTRA_FAST 0 75 #endif 76 77 /* 78 * Unconditionally aligning does not cost very much, so do it if unsure 79 * 80 * In fact, on modern x86 processors, strict alignment is faster whether 81 * in 32 or 64 bit mode. 82 */ 83 #ifndef STRICT_ALIGN 84 # define STRICT_ALIGN 1 /* !(defined(__i386) || defined (__amd64)) */ 85 #endif 86 87 /* 88 * You may choose to pre-set the hash table (might be faster on some 89 * modern cpus and large (>>64k) blocks, and also makes compression 90 * deterministic/repeatable when the configuration otherwise is the same). 91 */ 92 #ifndef INIT_HTAB 93 # define INIT_HTAB 0 94 #endif 95 96 /* 97 * Avoid assigning values to errno variable? for some embedding purposes 98 * (linux kernel for example), this is neccessary. NOTE: this breaks 99 * the documentation in lzf.h. 100 */ 101 #ifndef AVOID_ERRNO 102 # define AVOID_ERRNO 0 103 #endif 104 105 /* 106 * Wether to pass the LZF_STATE variable as argument, or allocate it 107 * on the stack. For small-stack environments, define this to 1. 108 * NOTE: this breaks the prototype in lzf.h. 109 */ 110 #ifndef LZF_STATE_ARG 111 # define LZF_STATE_ARG 0 112 #endif 113 114 /* 115 * Wether to add extra checks for input validity in lzf_decompress 116 * and return EINVAL if the input stream has been corrupted. This 117 * only shields against overflowing the input buffer and will not 118 * detect most corrupted streams. 119 * This check is not normally noticable on modern hardware 120 * (<1% slowdown), but might slow down older cpus considerably. 121 */ 122 #ifndef CHECK_INPUT 123 # define CHECK_INPUT 1 124 #endif 125 126 /*****************************************************************************/ 127 /* nothing should be changed below */ 128 129 typedef uint8_t u8; 130 typedef uint16_t u16; 131 132 #if !defined(_KERNEL) && !defined(STANDALONE) 133 typedef const u8 *LZF_STATE[1 << (LZF_HLOG)]; 134 #endif 135 136 #if ULTRA_FAST 137 # if defined(VERY_FAST) 138 # undef VERY_FAST 139 # endif 140 #endif 141 142 #if INIT_HTAB 143 # ifdef __cplusplus 144 # include <cstring> 145 # else 146 # include <string.h> 147 # endif 148 #endif 149 150 #endif 151 152