… | |
… | |
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 | |
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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 | |
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124 | /* |
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125 | * Whether the target CPU has a slow multiplication. This affects |
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126 | * the default hash function for the compressor, and enables a slightly |
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127 | * worse hash function that needs only shifts. |
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128 | */ |
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129 | #ifndef MULTIPLICATION_IS_SLOW |
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130 | # define MULTIPLICATION_IS_SLOW 0 |
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131 | #endif |
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132 | |
|
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133 | /* |
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134 | * If defined, then this data type will be used for storing offsets. |
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135 | * This can be useful if you want to use a huge hashtable, want to |
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136 | * conserve memory, or both, and your data fits into e.g. 64kb. |
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137 | * If instead you want to compress data > 4GB, then it's better to |
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138 | * to "#define LZF_USE_OFFSETS 0" instead. |
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139 | */ |
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140 | /*#define LZF_HSLOT unsigned short*/ |
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141 | |
|
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142 | /* |
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143 | * Whether to store pointers or offsets inside the hash table. On |
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144 | * 64 bit architetcures, pointers take up twice as much space, |
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145 | * and might also be slower. Default is to autodetect. |
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146 | */ |
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147 | /*#define LZF_USE_OFFSETS autodetect */ |
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148 | |
125 | /*****************************************************************************/ |
149 | /*****************************************************************************/ |
126 | /* nothing should be changed below */ |
150 | /* nothing should be changed below */ |
127 | |
151 | |
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152 | #ifdef __cplusplus |
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153 | # include <cstring> |
|
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154 | # include <climits> |
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155 | using namespace std; |
|
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156 | #else |
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157 | # include <string.h> |
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158 | # include <limits.h> |
|
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159 | #endif |
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160 | |
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161 | #ifndef LZF_USE_OFFSETS |
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162 | # if defined (WIN32) || defined (_WIN32) |
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163 | # define LZF_USE_OFFSETS defined(_M_X64) |
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164 | # else |
|
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165 | # if __cplusplus > 199711L |
|
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166 | # include <cstdint> |
|
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167 | # else |
|
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168 | # include <stdint.h> |
|
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169 | # endif |
|
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170 | # define LZF_USE_OFFSETS (UINTPTR_MAX > 0xffffffffU) |
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171 | # endif |
|
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172 | #endif |
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173 | |
128 | typedef unsigned char u8; |
174 | typedef unsigned char u8; |
129 | |
175 | |
130 | typedef const u8 *LZF_STATE[1 << (HLOG)]; |
176 | #ifdef LZF_HSLOT |
131 | |
177 | # define LZF_HSLOT_BIAS ((const u8 *)in_data) |
132 | #if !STRICT_ALIGN |
178 | #else |
133 | /* for unaligned accesses we need a 16 bit datatype. */ |
179 | # if LZF_USE_OFFSETS |
134 | # include <limits.h> |
180 | # define LZF_HSLOT_BIAS ((const u8 *)in_data) |
135 | # if USHRT_MAX == 65535 |
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136 | typedef unsigned short u16; |
|
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137 | # elif UINT_MAX == 65535 |
|
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138 | typedef unsigned int u16; |
181 | typedef unsigned int LZF_HSLOT; |
139 | # else |
182 | # else |
140 | # undef STRICT_ALIGN |
183 | # define LZF_HSLOT_BIAS 0 |
141 | # define STRICT_ALIGN 1 |
184 | typedef const u8 *LZF_HSLOT; |
142 | # endif |
185 | # endif |
143 | #endif |
186 | #endif |
144 | |
187 | |
|
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188 | typedef LZF_HSLOT LZF_STATE[1 << (HLOG)]; |
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189 | |
|
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190 | #if USHRT_MAX == 65535 |
|
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191 | typedef unsigned short u16; |
|
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192 | #elif UINT_MAX == 65535 |
|
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193 | typedef unsigned int u16; |
|
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194 | #else |
|
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195 | # undef STRICT_ALIGN |
|
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196 | # define STRICT_ALIGN 1 |
|
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197 | #endif |
|
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198 | |
145 | #if ULTRA_FAST |
199 | #if ULTRA_FAST |
146 | # if defined(VERY_FAST) |
|
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147 | # undef VERY_FAST |
200 | # undef VERY_FAST |
148 | # endif |
201 | #endif |
149 | #endif |
|
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150 | |
202 | |
151 | #if INIT_HTAB |
|
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152 | # ifdef __cplusplus |
|
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153 | # include <cstring> |
|
|
154 | # else |
|
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155 | # include <string.h> |
|
|
156 | # endif |
203 | #endif |
157 | #endif |
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158 | |
204 | |
159 | #endif |
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160 | |
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