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Comparing liblzf/lzfP.h (file contents):
Revision 1.8 by pcg, Tue Apr 20 18:11:57 2004 UTC vs.
Revision 1.15 by root, Thu Jun 21 22:11:34 2007 UTC

1/* 1/*
2 * Copyright (c) 2000-2003 Marc Alexander Lehmann <pcg@goof.com> 2 * Copyright (c) 2000-2005 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,
… …
37 */ 37 */
38 38
39#ifndef LZFP_h 39#ifndef LZFP_h
40#define LZFP_h 40#define LZFP_h
41 41
42#define STANDALONE /* at the moment, this is ok. */ 42#define STANDALONE 1 /* at the moment, this is ok. */
43 43
44#ifndef STANDALONE 44#ifndef STANDALONE
45# include "lzf.h" 45# include "lzf.h"
46#endif 46#endif
47 47
48/* 48/*
49 * size of hashtable is (1 << HLOG) * sizeof (char *) 49 * Size of hashtable is (1 << HLOG) * sizeof (char *)
50 * decompression is independent of the hash table size 50 * decompression is independent of the hash table size
51 * the difference between 15 and 14 is very small 51 * the difference between 15 and 14 is very small
52 * for small blocks (and 14 is also faster). 52 * for small blocks (and 14 is usually a bit faster).
53 * For a low-memory configuration, use HLOG == 13; 53 * For a low-memory/faster configuration, use HLOG == 13;
54 * For best compression, use 15 or 16. 54 * For best compression, use 15 or 16 (or more).
55 */ 55 */
56#ifndef HLOG 56#ifndef HLOG
57# define HLOG 14 57# define HLOG 15
58#endif 58#endif
59 59
60/* 60/*
61 * sacrifice some compression quality in favour of compression speed. 61 * Sacrifice very little compression quality in favour of compression speed.
62 * (roughly 1-2% worse compression for large blocks and 62 * 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) 63 * (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 */ 64 */
65
66#ifndef ULTRA_FAST 66#ifndef VERY_FAST
67# define ULTRA_FAST 1 67# define VERY_FAST 1
68#endif 68#endif
69 69
70/* 70/*
71 * unconditionally aligning does not cost very much, so do it if unsure 71 * Sacrifice some more compression quality in favour of compression speed.
72 * (roughly 1-2% worse compression for large blocks and
73 * 9-10% for small, redundant, blocks and >>20% better speed in both cases)
74 * In short: when in need for speed, enable this for binary data,
75 * possibly disable this for text data.
72 */ 76 */
73#ifndef STRICT_ALIGN 77#ifndef ULTRA_FAST
74# define STRICT_ALIGN !defined(__i386) 78# define ULTRA_FAST 0
75#endif 79#endif
76 80
77/* 81/*
78 * use string functions to copy memory. 82 * 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 */ 83 */
81#ifndef USE_MEMCPY 84#ifndef STRICT_ALIGN
82# define USE_MEMCPY 0 85# define STRICT_ALIGN !(defined(__i386) || defined (__amd64))
83#endif 86#endif
84 87
85/* 88/*
86 * you may choose to pre-set the hash table (might be faster on modern cpus 89 * You may choose to pre-set the hash table (might be faster on some
87 * and large (>>64k) blocks) 90 * modern cpus and large (>>64k) blocks, and also makes compression
91 * deterministic/repeatable when the configuration otherwise is the same).
88 */ 92 */
89#ifndef INIT_HTAB 93#ifndef INIT_HTAB
90# define INIT_HTAB 0 94# define INIT_HTAB 0
91#endif 95#endif
92 96
93/* 97/*
94 * avoid assigning values to errno variable? for some embedding purposes 98 * Avoid assigning values to errno variable? for some embedding purposes
95 * (linux kernel for example), this is neccessary. NOTE: this breaks 99 * (linux kernel for example), this is neccessary. NOTE: this breaks
96 * the documentation in lzf.h. 100 * the documentation in lzf.h.
97 */ 101 */
98#ifndef AVOID_ERRNO 102#ifndef AVOID_ERRNO
99# define AVOID_ERRNO 0 103# define AVOID_ERRNO 0
… …
104 * on the stack. For small-stack environments, define this to 1. 108 * on the stack. For small-stack environments, define this to 1.
105 * NOTE: this breaks the prototype in lzf.h. 109 * NOTE: this breaks the prototype in lzf.h.
106 */ 110 */
107#ifndef LZF_STATE_ARG 111#ifndef LZF_STATE_ARG
108# define LZF_STATE_ARG 0 112# define LZF_STATE_ARG 0
113#endif
114
115/*
116 * Wether to add extra checks for input validity in lzf_decompress
117 * and return EINVAL if the input stream has been corrupted. This
118 * only shields against overflowing the input buffer and will not
119 * detect most corrupted streams.
120 * This check is not normally noticable on modern hardware
121 * (<1% slowdown), but might slow down older cpus considerably.
122 */
123#ifndef CHECK_INPUT
124# define CHECK_INPUT 1
109#endif 125#endif
110 126
111/*****************************************************************************/ 127/*****************************************************************************/
112/* nothing should be changed below */ 128/* nothing should be changed below */
113 129
… …
126# undef STRICT_ALIGN 142# undef STRICT_ALIGN
127# define STRICT_ALIGN 1 143# define STRICT_ALIGN 1
128# endif 144# endif
129#endif 145#endif
130 146
131#if USE_MEMCPY || INIT_HTAB 147#if ULTRA_FAST
148# if defined(VERY_FAST)
149# undef VERY_FAST
150# endif
151#endif
152
153#if INIT_HTAB
154# ifdef __cplusplus
155# include <cstring>
156# else
132# include <string.h> 157# include <string.h>
158# endif
133#endif 159#endif
134 160
135#endif 161#endif
136 162

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