| 1 | /* |
1 | /* |
| 2 | * Copyright (c) 2000-2007 Marc Alexander Lehmann <schmorp@schmorp.de> |
2 | * Copyright (c) 2000-2008 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, |
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| 111 | u8 *op = (u8 *)out_data; |
111 | u8 *op = (u8 *)out_data; |
| 112 | const u8 *in_end = ip + in_len; |
112 | const u8 *in_end = ip + in_len; |
| 113 | u8 *out_end = op + out_len; |
113 | u8 *out_end = op + out_len; |
| 114 | const u8 *ref; |
114 | const u8 *ref; |
| 115 | |
115 | |
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116 | /* off requires a type wide enough to hold a general pointer difference. |
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117 | * ISO C doesn't have that (size_t might not be enough and ptrdiff_t only |
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118 | * works for differences within a single object). We also assume that no |
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119 | * no bit pattern traps. Since the only platform that is both non-POSIX |
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120 | * and fails to support both assumptions is windows 64 bit, we make a |
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121 | * special workaround for it. |
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122 | */ |
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123 | #if defined (WIN32) && defined (_M_X64) |
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124 | unsigned _int64 off; /* workaround for missing POSIX compliance */ |
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125 | #else |
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126 | unsigned long off; |
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127 | #endif |
| 116 | unsigned int hval; |
128 | unsigned int hval; |
| 117 | #if WIN32 |
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| 118 | unsigned _int64 off; /* workaround for microsoft bug (they claim to support POSIX) */ |
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| 119 | #else |
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| 120 | unsigned long off; |
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| 121 | #endif |
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| 122 | int lit; |
129 | int lit; |
| 123 | |
130 | |
| 124 | if (!in_len || !out_len) |
131 | if (!in_len || !out_len) |
| 125 | return 0; |
132 | return 0; |
| 126 | |
133 | |
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| 199 | while (len < maxlen && ref[len] == ip[len]); |
206 | while (len < maxlen && ref[len] == ip[len]); |
| 200 | |
207 | |
| 201 | break; |
208 | break; |
| 202 | } |
209 | } |
| 203 | |
210 | |
| 204 | len -= 2; |
211 | len -= 2; /* len is now #octets - 1 */ |
| 205 | ip++; |
212 | ip++; |
| 206 | |
213 | |
| 207 | if (len < 7) |
214 | if (len < 7) |
| 208 | { |
215 | { |
| 209 | *op++ = (off >> 8) + (len << 5); |
216 | *op++ = (off >> 8) + (len << 5); |
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| 213 | *op++ = (off >> 8) + ( 7 << 5); |
220 | *op++ = (off >> 8) + ( 7 << 5); |
| 214 | *op++ = len - 7; |
221 | *op++ = len - 7; |
| 215 | } |
222 | } |
| 216 | |
223 | |
| 217 | *op++ = off; |
224 | *op++ = off; |
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225 | lit = 0; op++; /* start run */ |
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226 | |
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227 | ip += len + 1; |
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228 | |
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229 | if (expect_false (ip > in_end - 2)) |
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230 | break; |
| 218 | |
231 | |
| 219 | #if ULTRA_FAST || VERY_FAST |
232 | #if ULTRA_FAST || VERY_FAST |
| 220 | ip += len; |
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| 221 | #if VERY_FAST && !ULTRA_FAST |
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| 222 | --ip; |
233 | --ip; |
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234 | # if VERY_FAST && !ULTRA_FAST |
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235 | --ip; |
| 223 | #endif |
236 | # endif |
| 224 | hval = FRST (ip); |
237 | hval = FRST (ip); |
| 225 | |
238 | |
| 226 | hval = NEXT (hval, ip); |
239 | hval = NEXT (hval, ip); |
| 227 | htab[IDX (hval)] = ip; |
240 | htab[IDX (hval)] = ip; |
| 228 | ip++; |
241 | ip++; |
| 229 | |
242 | |
| 230 | #if VERY_FAST && !ULTRA_FAST |
243 | # if VERY_FAST && !ULTRA_FAST |
| 231 | hval = NEXT (hval, ip); |
244 | hval = NEXT (hval, ip); |
| 232 | htab[IDX (hval)] = ip; |
245 | htab[IDX (hval)] = ip; |
| 233 | ip++; |
246 | ip++; |
| 234 | #endif |
247 | # endif |
| 235 | #else |
248 | #else |
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249 | ip -= len + 1; |
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250 | |
| 236 | do |
251 | do |
| 237 | { |
252 | { |
| 238 | hval = NEXT (hval, ip); |
253 | hval = NEXT (hval, ip); |
| 239 | htab[IDX (hval)] = ip; |
254 | htab[IDX (hval)] = ip; |
| 240 | ip++; |
255 | ip++; |
| 241 | } |
256 | } |
| 242 | while (len--); |
257 | while (len--); |
| 243 | #endif |
258 | #endif |
| 244 | |
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| 245 | lit = 0; op++; /* start run */ |
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| 246 | } |
259 | } |
| 247 | else |
260 | else |
| 248 | { |
261 | { |
| 249 | /* one more literal byte we must copy */ |
262 | /* one more literal byte we must copy */ |
| 250 | if (expect_false (op >= out_end)) |
263 | if (expect_false (op >= out_end)) |
