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Comparing liblzf/lzfP.h (file contents):
Revision 1.9 by root, Wed Mar 2 02:41:48 2005 UTC vs.
Revision 1.16 by root, Fri Nov 2 12:39:20 2007 UTC

1/* 1/*
2 * Copyright (c) 2000-2003 Marc Alexander Lehmann <pcg@goof.com> 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 *
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 * 13 *
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-
… …
37 */ 34 */
38 35
39#ifndef LZFP_h 36#ifndef LZFP_h
40#define LZFP_h 37#define LZFP_h
41 38
42#define STANDALONE /* at the moment, this is ok. */ 39#define STANDALONE 1 /* at the moment, this is ok. */
43 40
44#ifndef STANDALONE 41#ifndef STANDALONE
45# include "lzf.h" 42# include "lzf.h"
46#endif 43#endif
47 44
48/* 45/*
49 * size of hashtable is (1 << HLOG) * sizeof (char *) 46 * Size of hashtable is (1 << HLOG) * sizeof (char *)
50 * decompression is independent of the hash table size 47 * decompression is independent of the hash table size
51 * the difference between 15 and 14 is very small 48 * the difference between 15 and 14 is very small
52 * for small blocks (and 14 is also faster). 49 * for small blocks (and 14 is usually a bit faster).
53 * For a low-memory configuration, use HLOG == 13; 50 * For a low-memory/faster configuration, use HLOG == 13;
54 * For best compression, use 15 or 16. 51 * For best compression, use 15 or 16 (or more).
55 */ 52 */
56#ifndef HLOG 53#ifndef HLOG
57# define HLOG 14 54# define HLOG 15
58#endif 55#endif
59 56
60/* 57/*
61 * sacrifice some compression quality in favour of compression speed. 58 * Sacrifice very little compression quality in favour of compression speed.
62 * (roughly 1-2% worse compression for large blocks and 59 * This gives almost the same compression as the default code, and is
63 * 9-10% for small, redundant, blocks and >>20% better speed in both cases) 60 * (very roughly) 15% faster. This is the preferable mode of operation.
64 * In short: enable this for binary data, disable this for text data.
65 */ 61 */
62
66#ifndef ULTRA_FAST 63#ifndef VERY_FAST
67# define ULTRA_FAST 1 64# define VERY_FAST 1
68#endif 65#endif
69 66
70/* 67/*
71 * unconditionally aligning does not cost very much, so do it if unsure 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.
72 */ 73 */
73#ifndef STRICT_ALIGN 74#ifndef ULTRA_FAST
74# define STRICT_ALIGN !defined(__i386) 75# define ULTRA_FAST 0
75#endif 76#endif
76 77
77/* 78/*
78 * use string functions to copy memory. 79 * Unconditionally aligning does not cost very much, so do it if unsure
79 * this is usually a loss, even with glibc's optimized memcpy
80 */ 80 */
81#ifndef USE_MEMCPY 81#ifndef STRICT_ALIGN
82# define USE_MEMCPY 0 82# define STRICT_ALIGN !(defined(__i386) || defined (__amd64))
83#endif 83#endif
84 84
85/* 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 0
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 neccessary. NOTE: this breaks
96 * the documentation in lzf.h. 97 * the documentation in lzf.h.
97 */ 98 */
98#ifndef AVOID_ERRNO 99#ifndef AVOID_ERRNO
99# define AVOID_ERRNO 0 100# define AVOID_ERRNO 0
… …
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
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
109#endif 122#endif
110 123
111/*****************************************************************************/ 124/*****************************************************************************/
112/* nothing should be changed below */ 125/* nothing should be changed below */
113 126
… …
126# undef STRICT_ALIGN 139# undef STRICT_ALIGN
127# define STRICT_ALIGN 1 140# define STRICT_ALIGN 1
128# endif 141# endif
129#endif 142#endif
130 143
131#if USE_MEMCPY || INIT_HTAB 144#if ULTRA_FAST
145# if defined(VERY_FAST)
146# undef VERY_FAST
147# endif
148#endif
149
150#if INIT_HTAB
132# ifdef __cplusplus 151# ifdef __cplusplus
133# include <cstring> 152# include <cstring>
134# else 153# else
135# include <string.h> 154# include <string.h>
136# endif 155# endif

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