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Comparing liblzf/lzfP.h (file contents):
Revision 1.10 by root, Thu Mar 3 17:06:44 2005 UTC vs.
Revision 1.31 by root, Mon Jun 29 23:34:41 2015 UTC

1/* 1/*
2 * Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de> 2 * Copyright (c) 2000-2007 Marc Alexander Lehmann <schmorp@schmorp.de>
3 * 3 *
4 * Redistribution and use in source and binary forms, with or without modifica- 4 * Redistribution and use in source and binary forms, with or without modifica-
5 * tion, are permitted provided that the following conditions are met: 5 * tion, are permitted provided that the following conditions are met:
6 * 6 *
7 * 1. Redistributions of source code must retain the above copyright notice, 7 * 1. Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer. 8 * this list of conditions and the following disclaimer.
9 * 9 *
10 * 2. Redistributions in binary form must reproduce the above copyright 10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the 11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution. 12 * documentation and/or other materials provided with the distribution.
13 * 13 *
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- 17 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
… …
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- 21 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 22 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE. 23 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 * 24 *
28 * Alternatively, the contents of this file may be used under the terms of 25 * Alternatively, the contents of this file may be used under the terms of
29 * the GNU General Public License version 2 (the "GPL"), in which case the 26 * the GNU General Public License ("GPL") version 2 or any later version,
30 * provisions of the GPL are applicable instead of the above. If you wish to 27 * in which case the provisions of the GPL are applicable instead of
31 * allow the use of your version of this file only under the terms of the 28 * the above. If you wish to allow the use of your version of this file
32 * GPL and not to allow others to use your version of this file under the 29 * only under the terms of the GPL and not to allow others to use your
33 * BSD license, indicate your decision by deleting the provisions above and 30 * version of this file under the BSD license, indicate your decision
34 * replace them with the notice and other provisions required by the GPL. If 31 * by deleting the provisions above and replace them with the notice
35 * you do not delete the provisions above, a recipient may use your version 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
36 * of this file under either the BSD or the GPL. 34 * either the BSD or the GPL.
37 */ 35 */
38 36
39#ifndef LZFP_h 37#ifndef LZFP_h
40#define LZFP_h 38#define LZFP_h
41 39
42#define STANDALONE /* at the moment, this is ok. */ 40#define STANDALONE 1 /* at the moment, this is ok. */
43 41
44#ifndef STANDALONE 42#ifndef STANDALONE
45# include "lzf.h" 43# include "lzf.h"
46#endif 44#endif
47 45
48/* 46/*
49 * size of hashtable is (1 << HLOG) * sizeof (char *) 47 * Size of hashtable is (1 << HLOG) * sizeof (char *)
50 * decompression is independent of the hash table size 48 * decompression is independent of the hash table size
51 * the difference between 15 and 14 is very small 49 * the difference between 15 and 14 is very small
52 * for small blocks (and 14 is also faster). 50 * for small blocks (and 14 is usually a bit faster).
53 * For a low-memory configuration, use HLOG == 13; 51 * For a low-memory/faster configuration, use HLOG == 13;
54 * For best compression, use 15 or 16. 52 * For best compression, use 15 or 16 (or more, up to 22).
55 */ 53 */
56#ifndef HLOG 54#ifndef HLOG
57# define HLOG 14 55# define HLOG 16
58#endif 56#endif
59 57
60/* 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/*
61 * sacrifice some compression quality in favour of compression speed. 68 * Sacrifice some more compression quality in favour of compression speed.
62 * (roughly 1-2% worse compression for large blocks and 69 * (roughly 1-2% worse compression for large blocks and
63 * 9-10% for small, redundant, blocks and >>20% better speed in both cases) 70 * 9-10% for small, redundant, blocks and >>20% better speed in both cases)
64 * In short: enable this for binary data, disable this for text data. 71 * In short: when in need for speed, enable this for binary data,
72 * possibly disable this for text data.
65 */ 73 */
66#ifndef ULTRA_FAST 74#ifndef ULTRA_FAST
67# define ULTRA_FAST 1 75# define ULTRA_FAST 0
68#endif 76#endif
69 77
70/* 78/*
71 * unconditionally aligning does not cost very much, so do it if unsure 79 * Unconditionally aligning does not cost very much, so do it if unsure
72 */ 80 */
73#ifndef STRICT_ALIGN 81#ifndef STRICT_ALIGN
74# define STRICT_ALIGN !defined(__i386) 82# define STRICT_ALIGN !(defined(__i386) || defined (__amd64))
75#endif 83#endif
76 84
77/* 85/*
78 * use string functions to copy memory.
79 * this is usually a loss, even with glibc's optimized memcpy
80 */
81#ifndef USE_MEMCPY
82# define USE_MEMCPY 0
83#endif
84
85/*
86 * you may choose to pre-set the hash table (might be faster on modern cpus 86 * You may choose to pre-set the hash table (might be faster on some
87 * and large (>>64k) blocks) 87 * modern cpus and large (>>64k) blocks, and also makes compression
88 * deterministic/repeatable when the configuration otherwise is the same).
88 */ 89 */
89#ifndef INIT_HTAB 90#ifndef INIT_HTAB
90# define INIT_HTAB 0 91# define INIT_HTAB 1
91#endif 92#endif
92 93
93/* 94/*
94 * avoid assigning values to errno variable? for some embedding purposes 95 * Avoid assigning values to errno variable? for some embedding purposes
95 * (linux kernel for example), this is neccessary. NOTE: this breaks 96 * (linux kernel for example), this is necessary. NOTE: this breaks
96 * the documentation in lzf.h. 97 * the documentation in lzf.h. Avoiding errno has no speed impact.
97 */ 98 */
98#ifndef AVOID_ERRNO 99#ifndef AVOID_ERRNO
99# define AVOID_ERRNO 0 100# define AVOID_ERRNO 0
100#endif 101#endif
101 102
102/* 103/*
103 * Wether to pass the LZF_STATE variable as argument, or allocate it 104 * Whether to pass the LZF_STATE variable as argument, or allocate it
104 * on the stack. For small-stack environments, define this to 1. 105 * on the stack. For small-stack environments, define this to 1.
105 * NOTE: this breaks the prototype in lzf.h. 106 * NOTE: this breaks the prototype in lzf.h.
106 */ 107 */
107#ifndef LZF_STATE_ARG 108#ifndef LZF_STATE_ARG
108# define LZF_STATE_ARG 0 109# define LZF_STATE_ARG 0
109#endif 110#endif
110 111
112/*
113 * Whether 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 noticeable 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 * Whether the target CPU has a slow multiplication. This affects
126 * the default hash function for the compressor, and enables a slightly
127 * worse hash function that needs only shifts.
128 */
129#ifndef MULTIPLICATION_IS_SLOW
130# define MULTIPLICATION_IS_SLOW 0
131#endif
132
133/*
134 * If defined, then this data type will be used for storing offsets.
135 * This can be useful if you want to use a huge hashtable, want to
136 * conserve memory, or both, and your data fits into e.g. 64kb.
137 * If instead you want to compress data > 4GB, then it's better to
138 * to "#define LZF_USE_OFFSETS 0" instead.
139 */
140/*#define LZF_HSLOT unsigned short*/
141
142/*
143 * Whether to store pointers or offsets inside the hash table. On
144 * 64 bit architetcures, pointers take up twice as much space,
145 * and might also be slower. Default is to autodetect.
146 */
147/*#define LZF_USE_OFFSETS autodetect */
148
149/*
150 * Whether to optimise code for size, at the expense of speed. Use
151 * this when you are extremely tight on memory, perhaps in combination
152 * with AVOID_ERRNO 1 and CHECK_INPUT 0.
153 */
154#ifndef OPTIMISE_SIZE
155# ifdef __OPTIMIZE_SIZE__
156# define OPTIMISE_SIZE 1
157# else
158# define OPTIMISE_SIZE 0
159# endif
160#endif
161
111/*****************************************************************************/ 162/*****************************************************************************/
112/* nothing should be changed below */ 163/* nothing should be changed below */
113 164
165#ifdef __cplusplus
166# include <cstring>
167# include <climits>
168using namespace std;
169#else
170# include <string.h>
171# include <limits.h>
172#endif
173
174#if ULTRA_FAST
175# undef VERY_FAST
176#endif
177
178#ifndef LZF_USE_OFFSETS
179# ifdef _WIN32
180# define LZF_USE_OFFSETS defined(_M_X64)
181# else
182# if __cplusplus > 199711L
183# include <cstdint>
184# else
185# include <stdint.h>
186# endif
187# define LZF_USE_OFFSETS (UINTPTR_MAX > 0xffffffffU)
188# endif
189#endif
190
114typedef unsigned char u8; 191typedef unsigned char u8;
115 192
116typedef const u8 *LZF_STATE[1 << (HLOG)]; 193#ifdef LZF_HSLOT
117 194# define LZF_HSLOT_BIAS ((const u8 *)in_data)
118#if !STRICT_ALIGN 195#else
119/* for unaligned accesses we need a 16 bit datatype. */ 196# if LZF_USE_OFFSETS
120# include <limits.h> 197# define LZF_HSLOT_BIAS ((const u8 *)in_data)
121# if USHRT_MAX == 65535
122 typedef unsigned short u16;
123# elif UINT_MAX == 65535
124 typedef unsigned int u16; 198 typedef unsigned int LZF_HSLOT;
125# else 199# else
126# undef STRICT_ALIGN 200# define LZF_HSLOT_BIAS 0
127# define STRICT_ALIGN 1 201 typedef const u8 *LZF_HSLOT;
128# endif 202# endif
129#endif 203#endif
130 204
131#if USE_MEMCPY || INIT_HTAB 205#if USHRT_MAX == 65535
132# ifdef __cplusplus 206 typedef unsigned short u16;
133# include <cstring> 207#elif UINT_MAX == 65535
208 typedef unsigned int u16;
134# else 209#else
135# include <string.h> 210# undef STRICT_ALIGN
211# define STRICT_ALIGN 1
136# endif 212#endif
137#endif
138 213
139#endif 214#define LZF_MAX_LIT (1 << 5)
215#define LZF_MAX_OFF (1 << 13)
216#define LZF_MAX_REF ((1 << 8) + (1 << 3))
140 217
218typedef LZF_HSLOT LZF_STATE[1 << (HLOG)];
219
220typedef struct
221{
222 const u8 *first [1 << (6+8)]; /* most recent occurance of a match */
223 u16 prev [LZF_MAX_OFF]; /* how many bytes to go backwards for the next match */
224} LZF_STATE_BEST[1];
225
226#endif
227

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