ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/liblzf/lzfP.h
(Generate patch)

Comparing liblzf/lzfP.h (file contents):
Revision 1.17 by root, Mon Nov 5 23:28:40 2007 UTC vs.
Revision 1.30 by root, Mon Feb 23 23:46:10 2015 UTC

1/* 1/*
2 * Copyright (c) 2000-2007 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 * 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
15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 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- 17 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
… …
47 * Size of hashtable is (1 << HLOG) * sizeof (char *) 47 * Size of hashtable is (1 << HLOG) * sizeof (char *)
48 * decompression is independent of the hash table size 48 * decompression is independent of the hash table size
49 * the difference between 15 and 14 is very small 49 * the difference between 15 and 14 is very small
50 * for small blocks (and 14 is usually a bit faster). 50 * for small blocks (and 14 is usually a bit faster).
51 * For a low-memory/faster configuration, use HLOG == 13; 51 * For a low-memory/faster configuration, use HLOG == 13;
52 * For best compression, use 15 or 16 (or more). 52 * For best compression, use 15 or 16 (or more, up to 22).
53 */ 53 */
54#ifndef HLOG 54#ifndef HLOG
55# define HLOG 15 55# define HLOG 16
56#endif 56#endif
57 57
58/* 58/*
59 * Sacrifice very little compression quality in favour of compression speed. 59 * Sacrifice very little compression quality in favour of compression speed.
60 * This gives almost the same compression as the default code, and is 60 * This gives almost the same compression as the default code, and is
61 * (very roughly) 15% faster. This is the preferable mode of operation. 61 * (very roughly) 15% faster. This is the preferred mode of operation.
62 */ 62 */
63
64#ifndef VERY_FAST 63#ifndef VERY_FAST
65# define VERY_FAST 1 64# define VERY_FAST 1
66#endif 65#endif
67 66
68/* 67/*
… …
87 * You may choose to pre-set the hash table (might be faster on some 86 * You may choose to pre-set the hash table (might be faster on some
88 * modern cpus and large (>>64k) blocks, and also makes compression 87 * modern cpus and large (>>64k) blocks, and also makes compression
89 * deterministic/repeatable when the configuration otherwise is the same). 88 * deterministic/repeatable when the configuration otherwise is the same).
90 */ 89 */
91#ifndef INIT_HTAB 90#ifndef INIT_HTAB
92# define INIT_HTAB 0 91# define INIT_HTAB 1
93#endif 92#endif
94 93
95/* 94/*
96 * Avoid assigning values to errno variable? for some embedding purposes 95 * Avoid assigning values to errno variable? for some embedding purposes
97 * (linux kernel for example), this is neccessary. NOTE: this breaks 96 * (linux kernel for example), this is necessary. NOTE: this breaks
98 * the documentation in lzf.h. 97 * the documentation in lzf.h. Avoiding errno has no speed impact.
99 */ 98 */
100#ifndef AVOID_ERRNO 99#ifndef AVOID_ERRNO
101# define AVOID_ERRNO 0 100# define AVOID_ERRNO 0
102#endif 101#endif
103 102
104/* 103/*
105 * 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
106 * on the stack. For small-stack environments, define this to 1. 105 * on the stack. For small-stack environments, define this to 1.
107 * NOTE: this breaks the prototype in lzf.h. 106 * NOTE: this breaks the prototype in lzf.h.
108 */ 107 */
109#ifndef LZF_STATE_ARG 108#ifndef LZF_STATE_ARG
110# define LZF_STATE_ARG 0 109# define LZF_STATE_ARG 0
111#endif 110#endif
112 111
113/* 112/*
114 * Wether to add extra checks for input validity in lzf_decompress 113 * Whether to add extra checks for input validity in lzf_decompress
115 * and return EINVAL if the input stream has been corrupted. This 114 * and return EINVAL if the input stream has been corrupted. This
116 * only shields against overflowing the input buffer and will not 115 * only shields against overflowing the input buffer and will not
117 * detect most corrupted streams. 116 * detect most corrupted streams.
118 * This check is not normally noticable on modern hardware 117 * This check is not normally noticeable on modern hardware
119 * (<1% slowdown), but might slow down older cpus considerably. 118 * (<1% slowdown), but might slow down older cpus considerably.
120 */ 119 */
121#ifndef CHECK_INPUT 120#ifndef CHECK_INPUT
122# define CHECK_INPUT 1 121# define CHECK_INPUT 1
123#endif 122#endif
124 123
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
125/*****************************************************************************/ 162/*****************************************************************************/
126/* nothing should be changed below */ 163/* nothing should be changed below */
127 164
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#ifndef LZF_USE_OFFSETS
175# ifdef _WIN32
176# define LZF_USE_OFFSETS defined(_M_X64)
177# else
178# if __cplusplus > 199711L
179# include <cstdint>
180# else
181# include <stdint.h>
182# endif
183# define LZF_USE_OFFSETS (UINTPTR_MAX > 0xffffffffU)
184# endif
185#endif
186
128typedef unsigned char u8; 187typedef unsigned char u8;
129 188
130typedef const u8 *LZF_STATE[1 << (HLOG)]; 189#ifdef LZF_HSLOT
131 190# define LZF_HSLOT_BIAS ((const u8 *)in_data)
132#if !STRICT_ALIGN 191#else
133/* for unaligned accesses we need a 16 bit datatype. */ 192# if LZF_USE_OFFSETS
134# include <limits.h> 193# define LZF_HSLOT_BIAS ((const u8 *)in_data)
135# if USHRT_MAX == 65535
136 typedef unsigned short u16;
137# elif UINT_MAX == 65535
138 typedef unsigned int u16; 194 typedef unsigned int LZF_HSLOT;
139# else 195# else
140# undef STRICT_ALIGN 196# define LZF_HSLOT_BIAS 0
141# define STRICT_ALIGN 1 197 typedef const u8 *LZF_HSLOT;
142# endif 198# endif
143#endif 199#endif
144 200
201typedef LZF_HSLOT LZF_STATE[1 << (HLOG)];
202
203#if USHRT_MAX == 65535
204 typedef unsigned short u16;
205#elif UINT_MAX == 65535
206 typedef unsigned int u16;
207#else
208# undef STRICT_ALIGN
209# define STRICT_ALIGN 1
210#endif
211
145#if ULTRA_FAST 212#if ULTRA_FAST
146# if defined(VERY_FAST)
147# undef VERY_FAST 213# undef VERY_FAST
148# endif 214#endif
149#endif
150 215
151#if INIT_HTAB
152# ifdef __cplusplus
153# include <cstring>
154# else
155# include <string.h>
156# endif 216#endif
157#endif
158 217
159#endif
160

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines