]> git.saurik.com Git - redis.git/blame - src/lzfP.h
rdbLoad() should check REDIS_RDB_VERSION instead of hardcoded number.
[redis.git] / src / lzfP.h
CommitLineData
d0751937 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#define STANDALONE 1 /* at the moment, this is ok. */
41
42#ifndef STANDALONE
43# include "lzf.h"
44#endif
45
46/*
47 * Size of hashtable is (1 << HLOG) * sizeof (char *)
48 * decompression is independent of the hash table size
49 * the difference between 15 and 14 is very small
50 * for small blocks (and 14 is usually a bit faster).
51 * For a low-memory/faster configuration, use HLOG == 13;
52 * For best compression, use 15 or 16 (or more, up to 23).
53 */
54#ifndef HLOG
55# define HLOG 16
56#endif
57
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/*
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.
73 */
74#ifndef ULTRA_FAST
75# define ULTRA_FAST 0
76#endif
77
78/*
79 * Unconditionally aligning does not cost very much, so do it if unsure
80 */
81#ifndef STRICT_ALIGN
82# define STRICT_ALIGN !(defined(__i386) || defined (__amd64))
83#endif
84
85/*
86 * You may choose to pre-set the hash table (might be faster on some
87 * modern cpus and large (>>64k) blocks, and also makes compression
88 * deterministic/repeatable when the configuration otherwise is the same).
89 */
90#ifndef INIT_HTAB
b0553789 91# define INIT_HTAB 0
d0751937 92#endif
93
94/*
95 * Avoid assigning values to errno variable? for some embedding purposes
96 * (linux kernel for example), this is neccessary. NOTE: this breaks
97 * the documentation in lzf.h.
98 */
99#ifndef AVOID_ERRNO
100# define AVOID_ERRNO 0
101#endif
102
103/*
104 * Wether to pass the LZF_STATE variable as argument, or allocate it
105 * on the stack. For small-stack environments, define this to 1.
106 * NOTE: this breaks the prototype in lzf.h.
107 */
108#ifndef LZF_STATE_ARG
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
122#endif
123
124/*****************************************************************************/
125/* nothing should be changed below */
126
127typedef unsigned char u8;
128
129typedef const u8 *LZF_STATE[1 << (HLOG)];
130
131#if !STRICT_ALIGN
132/* for unaligned accesses we need a 16 bit datatype. */
133# include <limits.h>
134# if USHRT_MAX == 65535
135 typedef unsigned short u16;
136# elif UINT_MAX == 65535
137 typedef unsigned int u16;
138# else
139# undef STRICT_ALIGN
140# define STRICT_ALIGN 1
141# endif
142#endif
143
144#if ULTRA_FAST
145# if defined(VERY_FAST)
146# undef VERY_FAST
147# endif
148#endif
149
150#if INIT_HTAB
151# ifdef __cplusplus
152# include <cstring>
153# else
154# include <string.h>
155# endif
156#endif
157
158#endif
159