• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 22).
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
91 # define INIT_HTAB 0
92 #endif
93 
94 /*
95  * Avoid assigning values to errno variable? for some embedding purposes
96  * (linux kernel for example), this is necessary. NOTE: this breaks
97  * the documentation in lzf.h. Avoiding errno has no speed impact.
98  */
99 #ifndef AVOID_ERRNO
100 # define AVOID_ERRNO 0
101 #endif
102 
103 /*
104  * Whether 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  * 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 to store pointers or offsets inside the hash table. On
126  * 64 bit architetcures, pointers take up twice as much space,
127  * and might also be slower. Default is to autodetect.
128  */
129 /*#define LZF_USER_OFFSETS autodetect */
130 
131 /*****************************************************************************/
132 /* nothing should be changed below */
133 
134 #ifdef __cplusplus
135 # include <cstring>
136 # include <climits>
137 using namespace std;
138 #else
139 # include <string.h>
140 # include <limits.h>
141 #endif
142 
143 #ifndef LZF_USE_OFFSETS
144 # if defined (WIN32)
145 #  define LZF_USE_OFFSETS defined(_M_X64)
146 # else
147 #  if __cplusplus > 199711L
148 #   include <cstdint>
149 #  else
150 #   include <stdint.h>
151 #  endif
152 #  define LZF_USE_OFFSETS (UINTPTR_MAX > 0xffffffffU)
153 # endif
154 #endif
155 
156 typedef unsigned char u8;
157 
158 #if LZF_USE_OFFSETS
159 # define LZF_HSLOT_BIAS ((const u8 *)in_data)
160   typedef unsigned int LZF_HSLOT;
161 #else
162 # define LZF_HSLOT_BIAS 0
163   typedef const u8 *LZF_HSLOT;
164 #endif
165 
166 typedef LZF_HSLOT LZF_STATE[1 << (HLOG)];
167 
168 #if !STRICT_ALIGN
169 /* for unaligned accesses we need a 16 bit datatype. */
170 # if USHRT_MAX == 65535
171     typedef unsigned short u16;
172 # elif UINT_MAX == 65535
173     typedef unsigned int u16;
174 # else
175 #  undef STRICT_ALIGN
176 #  define STRICT_ALIGN 1
177 # endif
178 #endif
179 
180 #if ULTRA_FAST
181 # undef VERY_FAST
182 #endif
183 
184 #endif
185 
186