Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 1 | #include "./static_dict.h" |
| 2 | |
| 3 | #include <algorithm> |
| 4 | |
| 5 | #include "./dictionary.h" |
| 6 | #include "./find_match_length.h" |
| 7 | #include "./static_dict_lut.h" |
| 8 | #include "./transform.h" |
| 9 | |
| 10 | namespace brotli { |
| 11 | |
| 12 | inline uint32_t Hash(const uint8_t *data) { |
| 13 | uint32_t h = BROTLI_UNALIGNED_LOAD32(data) * kDictHashMul32; |
| 14 | // The higher bits contain more mixture from the multiplication, |
| 15 | // so we take our results from there. |
| 16 | return h >> (32 - kDictNumBits); |
| 17 | } |
| 18 | |
| 19 | inline void AddMatch(int distance, int len, int len_code, int* matches) { |
| 20 | matches[len] = std::min(matches[len], (distance << 5) + len_code); |
| 21 | } |
| 22 | |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 23 | inline int DictMatchLength(const uint8_t* data, int id, int len, int maxlen) { |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 24 | const int offset = kBrotliDictionaryOffsetsByLength[len] + len * id; |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 25 | return FindMatchLengthWithLimit(&kBrotliDictionary[offset], data, |
| 26 | std::min(len, maxlen)); |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 27 | } |
| 28 | |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 29 | inline bool IsMatch(DictWord w, const uint8_t* data, int max_length) { |
| 30 | if (w.len > max_length) return false; |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 31 | const int offset = kBrotliDictionaryOffsetsByLength[w.len] + w.len * w.idx; |
| 32 | const uint8_t* dict = &kBrotliDictionary[offset]; |
| 33 | if (w.transform == 0) { |
| 34 | // Match against base dictionary word. |
| 35 | return FindMatchLengthWithLimit(dict, data, w.len) == w.len; |
| 36 | } else if (w.transform == 10) { |
| 37 | // Match against uppercase first transform. |
| 38 | // Note that there are only ASCII uppercase words in the lookup table. |
| 39 | return (dict[0] >= 'a' && dict[0] <= 'z' && |
| 40 | (dict[0] ^ 32) == data[0] && |
| 41 | FindMatchLengthWithLimit(&dict[1], &data[1], w.len - 1) == |
| 42 | w.len - 1); |
| 43 | } else { |
| 44 | // Match against uppercase all transform. |
| 45 | // Note that there are only ASCII uppercase words in the lookup table. |
| 46 | for (int i = 0; i < w.len; ++i) { |
| 47 | if (dict[i] >= 'a' && dict[i] <= 'z') { |
| 48 | if ((dict[i] ^ 32) != data[i]) return false; |
| 49 | } else { |
| 50 | if (dict[i] != data[i]) return false; |
| 51 | } |
| 52 | } |
| 53 | return true; |
| 54 | } |
| 55 | } |
| 56 | |
| 57 | bool FindAllStaticDictionaryMatches(const uint8_t* data, |
| 58 | int min_length, |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 59 | int max_length, |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 60 | int* matches) { |
| 61 | bool found_match = false; |
| 62 | uint32_t key = Hash(data); |
| 63 | uint32_t bucket = kStaticDictionaryBuckets[key]; |
| 64 | if (bucket != 0) { |
| 65 | int num = bucket & 0xff; |
| 66 | int offset = bucket >> 8; |
| 67 | for (int i = 0; i < num; ++i) { |
| 68 | const DictWord w = kStaticDictionaryWords[offset + i]; |
| 69 | const int l = w.len; |
| 70 | const int n = 1 << kBrotliDictionarySizeBitsByLength[l]; |
| 71 | const int id = w.idx; |
| 72 | if (w.transform == 0) { |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 73 | const int matchlen = DictMatchLength(data, id, l, max_length); |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 74 | // Transform "" + kIdentity + "" |
| 75 | if (matchlen == l) { |
| 76 | AddMatch(id, l, l, matches); |
| 77 | found_match = true; |
| 78 | } |
Marcin Karpinski | 21ac39f | 2015-09-21 21:04:07 +0200 | [diff] [blame] | 79 | // Transforms "" + kOmitLast1 + "" and "" + kOmitLast1 + "ing " |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 80 | if (matchlen >= l - 1) { |
| 81 | AddMatch(id + 12 * n, l - 1, l, matches); |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 82 | if (l + 2 < max_length && |
| 83 | data[l - 1] == 'i' && data[l] == 'n' && data[l + 1] == 'g' && |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 84 | data[l + 2] == ' ') { |
| 85 | AddMatch(id + 49 * n, l + 3, l, matches); |
| 86 | } |
| 87 | found_match = true; |
| 88 | } |
| 89 | // Transform "" + kOmitLastN + "" (N = 2 .. 9) |
| 90 | int minlen = std::max<int>(min_length, l - 9); |
| 91 | int maxlen = std::min<int>(matchlen, l - 2); |
| 92 | for (int len = minlen; len <= maxlen; ++len) { |
| 93 | AddMatch(id + kOmitLastNTransforms[l - len] * n, len, l, matches); |
| 94 | found_match = true; |
| 95 | } |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 96 | if (matchlen < l || l + 6 >= max_length) { |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 97 | continue; |
| 98 | } |
| 99 | const uint8_t* s = &data[l]; |
| 100 | // Transforms "" + kIdentity + <suffix> |
| 101 | if (s[0] == ' ') { |
| 102 | AddMatch(id + n, l + 1, l, matches); |
| 103 | if (s[1] == 'a') { |
| 104 | if (s[2] == ' ') { |
| 105 | AddMatch(id + 28 * n, l + 3, l, matches); |
| 106 | } else if (s[2] == 's') { |
| 107 | if (s[3] == ' ') AddMatch(id + 46 * n, l + 4, l, matches); |
| 108 | } else if (s[2] == 't') { |
| 109 | if (s[3] == ' ') AddMatch(id + 60 * n, l + 4, l, matches); |
| 110 | } else if (s[2] == 'n') { |
| 111 | if (s[3] == 'd' && s[4] == ' ') { |
| 112 | AddMatch(id + 10 * n, l + 5, l, matches); |
| 113 | } |
| 114 | } |
| 115 | } else if (s[1] == 'b') { |
| 116 | if (s[2] == 'y' && s[3] == ' ') { |
| 117 | AddMatch(id + 38 * n, l + 4, l, matches); |
| 118 | } |
| 119 | } else if (s[1] == 'i') { |
| 120 | if (s[2] == 'n') { |
| 121 | if (s[3] == ' ') AddMatch(id + 16 * n, l + 4, l, matches); |
| 122 | } else if (s[2] == 's') { |
| 123 | if (s[3] == ' ') AddMatch(id + 47 * n, l + 4, l, matches); |
| 124 | } |
| 125 | } else if (s[1] == 'f') { |
| 126 | if (s[2] == 'o') { |
| 127 | if (s[3] == 'r' && s[4] == ' ') { |
| 128 | AddMatch(id + 25 * n, l + 5, l, matches); |
| 129 | } |
| 130 | } else if (s[2] == 'r') { |
| 131 | if (s[3] == 'o' && s[4] == 'm' && s[5] == ' ') { |
| 132 | AddMatch(id + 37 * n, l + 6, l, matches); |
| 133 | } |
| 134 | } |
| 135 | } else if (s[1] == 'o') { |
| 136 | if (s[2] == 'f') { |
| 137 | if (s[3] == ' ') AddMatch(id + 8 * n, l + 4, l, matches); |
| 138 | } else if (s[2] == 'n') { |
| 139 | if (s[3] == ' ') AddMatch(id + 45 * n, l + 4, l, matches); |
| 140 | } |
| 141 | } else if (s[1] == 'n') { |
| 142 | if (s[2] == 'o' && s[3] == 't' && s[4] == ' ') { |
| 143 | AddMatch(id + 80 * n, l + 5, l, matches); |
| 144 | } |
| 145 | } else if (s[1] == 't') { |
| 146 | if (s[2] == 'h') { |
| 147 | if (s[3] == 'e') { |
| 148 | if (s[4] == ' ') AddMatch(id + 5 * n, l + 5, l, matches); |
| 149 | } else if (s[3] == 'a') { |
| 150 | if (s[4] == 't' && s[5] == ' ') { |
| 151 | AddMatch(id + 29 * n, l + 6, l, matches); |
| 152 | } |
| 153 | } |
| 154 | } else if (s[2] == 'o') { |
| 155 | if (s[3] == ' ') AddMatch(id + 17 * n, l + 4, l, matches); |
| 156 | } |
| 157 | } else if (s[1] == 'w') { |
| 158 | if (s[2] == 'i' && s[3] == 't' && s[4] == 'h' && s[5] == ' ') { |
| 159 | AddMatch(id + 35 * n, l + 6, l, matches); |
| 160 | } |
| 161 | } |
| 162 | } else if (s[0] == '"') { |
| 163 | AddMatch(id + 19 * n, l + 1, l, matches); |
| 164 | if (s[1] == '>') { |
| 165 | AddMatch(id + 21 * n, l + 2, l, matches); |
| 166 | } |
| 167 | } else if (s[0] == '.') { |
| 168 | AddMatch(id + 20 * n, l + 1, l, matches); |
| 169 | if (s[1] == ' ') { |
| 170 | AddMatch(id + 31 * n, l + 2, l, matches); |
| 171 | if (s[2] == 'T' && s[3] == 'h') { |
| 172 | if (s[4] == 'e') { |
| 173 | if (s[5] == ' ') AddMatch(id + 43 * n, l + 6, l, matches); |
| 174 | } else if (s[4] == 'i') { |
| 175 | if (s[5] == 's' && s[6] == ' ') { |
| 176 | AddMatch(id + 75 * n, l + 7, l, matches); |
| 177 | } |
| 178 | } |
| 179 | } |
| 180 | } |
| 181 | } else if (s[0] == ',') { |
| 182 | AddMatch(id + 76 * n, l + 1, l, matches); |
| 183 | if (s[1] == ' ') { |
| 184 | AddMatch(id + 14 * n, l + 2, l, matches); |
| 185 | } |
| 186 | } else if (s[0] == '\n') { |
| 187 | AddMatch(id + 22 * n, l + 1, l, matches); |
| 188 | if (s[1] == '\t') { |
| 189 | AddMatch(id + 50 * n, l + 2, l, matches); |
| 190 | } |
| 191 | } else if (s[0] == ']') { |
| 192 | AddMatch(id + 24 * n, l + 1, l, matches); |
| 193 | } else if (s[0] == '\'') { |
| 194 | AddMatch(id + 36 * n, l + 1, l, matches); |
| 195 | } else if (s[0] == ':') { |
| 196 | AddMatch(id + 51 * n, l + 1, l, matches); |
| 197 | } else if (s[0] == '(') { |
| 198 | AddMatch(id + 57 * n, l + 1, l, matches); |
| 199 | } else if (s[0] == '=') { |
| 200 | if (s[1] == '"') { |
| 201 | AddMatch(id + 70 * n, l + 2, l, matches); |
| 202 | } else if (s[1] == '\'') { |
| 203 | AddMatch(id + 86 * n, l + 2, l, matches); |
| 204 | } |
| 205 | } else if (s[0] == 'a') { |
| 206 | if (s[1] == 'l' && s[2] == ' ') { |
| 207 | AddMatch(id + 84 * n, l + 3, l, matches); |
| 208 | } |
| 209 | } else if (s[0] == 'e') { |
| 210 | if (s[1] == 'd') { |
| 211 | if (s[2] == ' ') AddMatch(id + 53 * n, l + 3, l, matches); |
| 212 | } else if (s[1] == 'r') { |
| 213 | if (s[2] == ' ') AddMatch(id + 82 * n, l + 3, l, matches); |
| 214 | } else if (s[1] == 's') { |
| 215 | if (s[2] == 't' && s[3] == ' ') { |
| 216 | AddMatch(id + 95 * n, l + 4, l, matches); |
| 217 | } |
| 218 | } |
| 219 | } else if (s[0] == 'f') { |
| 220 | if (s[1] == 'u' && s[2] == 'l' && s[3] == ' ') { |
| 221 | AddMatch(id + 90 * n, l + 4, l, matches); |
| 222 | } |
| 223 | } else if (s[0] == 'i') { |
| 224 | if (s[1] == 'v') { |
| 225 | if (s[2] == 'e' && s[3] == ' ') { |
| 226 | AddMatch(id + 92 * n, l + 4, l, matches); |
| 227 | } |
| 228 | } else if (s[1] == 'z') { |
| 229 | if (s[2] == 'e' && s[3] == ' ') { |
| 230 | AddMatch(id + 100 * n, l + 4, l, matches); |
| 231 | } |
| 232 | } |
| 233 | } else if (s[0] == 'l') { |
| 234 | if (s[1] == 'e') { |
| 235 | if (s[2] == 's' && s[3] == 's' && s[4] == ' ') { |
| 236 | AddMatch(id + 93 * n, l + 5, l, matches); |
| 237 | } |
| 238 | } else if (s[1] == 'y') { |
| 239 | if (s[2] == ' ') AddMatch(id + 61 * n, l + 3, l, matches); |
| 240 | } |
| 241 | } else if (s[0] == 'o') { |
| 242 | if (s[1] == 'u' && s[2] == 's' && s[3] == ' ') { |
| 243 | AddMatch(id + 106 * n, l + 4, l, matches); |
| 244 | } |
| 245 | } |
| 246 | } else { |
| 247 | // Set t=0 for kUppercaseFirst and t=1 for kUppercaseAll transform. |
| 248 | const int t = w.transform - 10; |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 249 | if (!IsMatch(w, data, max_length)) { |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 250 | continue; |
| 251 | } |
| 252 | // Transform "" + kUppercase{First,All} + "" |
| 253 | AddMatch(id + (t ? 44 : 9) * n, l, l, matches); |
| 254 | found_match = true; |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 255 | if (l + 1 >= max_length) { |
| 256 | continue; |
| 257 | } |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 258 | // Transforms "" + kUppercase{First,All} + <suffix> |
| 259 | const uint8_t* s = &data[l]; |
| 260 | if (s[0] == ' ') { |
| 261 | AddMatch(id + (t ? 68 : 4) * n, l + 1, l, matches); |
| 262 | } else if (s[0] == '"') { |
| 263 | AddMatch(id + (t ? 87 : 66) * n, l + 1, l, matches); |
| 264 | if (s[1] == '>') { |
| 265 | AddMatch(id + (t ? 97 : 69) * n, l + 2, l, matches); |
| 266 | } |
| 267 | } else if (s[0] == '.') { |
| 268 | AddMatch(id + (t ? 101 : 79) * n, l + 1, l, matches); |
| 269 | if (s[1] == ' ') { |
| 270 | AddMatch(id + (t ? 114 : 88) * n, l + 2, l, matches); |
| 271 | } |
| 272 | } else if (s[0] == ',') { |
| 273 | AddMatch(id + (t ? 112 : 99) * n, l + 1, l, matches); |
| 274 | if (s[1] == ' ') { |
| 275 | AddMatch(id + (t ? 107 : 58) * n, l + 2, l, matches); |
| 276 | } |
| 277 | } else if (s[0] == '\'') { |
| 278 | AddMatch(id + (t ? 94 : 74) * n, l + 1, l, matches); |
| 279 | } else if (s[0] == '(') { |
| 280 | AddMatch(id + (t ? 113 : 78) * n, l + 1, l, matches); |
| 281 | } else if (s[0] == '=') { |
| 282 | if (s[1] == '"') { |
| 283 | AddMatch(id + (t ? 105 : 104) * n, l + 2, l, matches); |
| 284 | } else if (s[1] == '\'') { |
| 285 | AddMatch(id + (t ? 116 : 108) * n, l + 2, l, matches); |
| 286 | } |
| 287 | } |
| 288 | } |
| 289 | } |
| 290 | } |
| 291 | // Transforms with prefixes " " and "." |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 292 | if (max_length >= 5 && (data[0] == ' ' || data[0] == '.')) { |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 293 | bool is_space = (data[0] == ' '); |
| 294 | key = Hash(&data[1]); |
| 295 | bucket = kStaticDictionaryBuckets[key]; |
| 296 | int num = bucket & 0xff; |
| 297 | int offset = bucket >> 8; |
| 298 | for (int i = 0; i < num; ++i) { |
| 299 | const DictWord w = kStaticDictionaryWords[offset + i]; |
| 300 | const int l = w.len; |
| 301 | const int n = 1 << kBrotliDictionarySizeBitsByLength[l]; |
| 302 | const int id = w.idx; |
| 303 | if (w.transform == 0) { |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 304 | if (!IsMatch(w, &data[1], max_length - 1)) { |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 305 | continue; |
| 306 | } |
| 307 | // Transforms " " + kIdentity + "" and "." + kIdentity + "" |
| 308 | AddMatch(id + (is_space ? 6 : 32) * n, l + 1, l, matches); |
| 309 | found_match = true; |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 310 | if (l + 2 >= max_length) { |
| 311 | continue; |
| 312 | } |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 313 | // Transforms " " + kIdentity + <suffix> and "." + kIdentity + <suffix> |
| 314 | const uint8_t* s = &data[l + 1]; |
| 315 | if (s[0] == ' ') { |
| 316 | AddMatch(id + (is_space ? 2 : 77) * n, l + 2, l, matches); |
| 317 | } else if (s[0] == '(') { |
| 318 | AddMatch(id + (is_space ? 89 : 67) * n, l + 2, l, matches); |
| 319 | } else if (is_space) { |
| 320 | if (s[0] == ',') { |
| 321 | AddMatch(id + 103 * n, l + 2, l, matches); |
| 322 | if (s[1] == ' ') { |
| 323 | AddMatch(id + 33 * n, l + 3, l, matches); |
| 324 | } |
| 325 | } else if (s[0] == '.') { |
| 326 | AddMatch(id + 71 * n, l + 2, l, matches); |
| 327 | if (s[1] == ' ') { |
| 328 | AddMatch(id + 52 * n, l + 3, l, matches); |
| 329 | } |
| 330 | } else if (s[0] == '=') { |
| 331 | if (s[1] == '"') { |
| 332 | AddMatch(id + 81 * n, l + 3, l, matches); |
| 333 | } else if (s[1] == '\'') { |
| 334 | AddMatch(id + 98 * n, l + 3, l, matches); |
| 335 | } |
| 336 | } |
| 337 | } |
| 338 | } else if (is_space) { |
| 339 | // Set t=0 for kUppercaseFirst and t=1 for kUppercaseAll transform. |
| 340 | const int t = w.transform - 10; |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 341 | if (!IsMatch(w, &data[1], max_length - 1)) { |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 342 | continue; |
| 343 | } |
| 344 | // Transforms " " + kUppercase{First,All} + "" |
| 345 | AddMatch(id + (t ? 85 : 30) * n, l + 1, l, matches); |
| 346 | found_match = true; |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 347 | if (l + 2 >= max_length) { |
| 348 | continue; |
| 349 | } |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 350 | // Transforms " " + kUppercase{First,All} + <suffix> |
| 351 | const uint8_t* s = &data[l + 1]; |
| 352 | if (s[0] == ' ') { |
| 353 | AddMatch(id + (t ? 83 : 15) * n, l + 2, l, matches); |
| 354 | } else if (s[0] == ',') { |
| 355 | if (t == 0) { |
| 356 | AddMatch(id + 109 * n, l + 2, l, matches); |
| 357 | } |
| 358 | if (s[1] == ' ') { |
| 359 | AddMatch(id + (t ? 111 : 65) * n, l + 3, l, matches); |
| 360 | } |
| 361 | } else if (s[0] == '.') { |
| 362 | AddMatch(id + (t ? 115 : 96) * n, l + 2, l, matches); |
| 363 | if (s[1] == ' ') { |
| 364 | AddMatch(id + (t ? 117 : 91) * n, l + 3, l, matches); |
| 365 | } |
| 366 | } else if (s[0] == '=') { |
| 367 | if (s[1] == '"') { |
| 368 | AddMatch(id + (t ? 110 : 118) * n, l + 3, l, matches); |
| 369 | } else if (s[1] == '\'') { |
| 370 | AddMatch(id + (t ? 119 : 120) * n, l + 3, l, matches); |
| 371 | } |
| 372 | } |
| 373 | } |
| 374 | } |
| 375 | } |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 376 | if (max_length >= 6) { |
| 377 | // Transforms with prefixes "e ", "s ", ", " and "\xc2\xa0" |
| 378 | if ((data[1] == ' ' && |
| 379 | (data[0] == 'e' || data[0] == 's' || data[0] == ',')) || |
Lode Vandevenne | 6511d6b | 2015-08-28 16:09:23 +0200 | [diff] [blame] | 380 | (data[0] == 0xc2 && data[1] == 0xa0)) { |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 381 | key = Hash(&data[2]); |
| 382 | bucket = kStaticDictionaryBuckets[key]; |
| 383 | int num = bucket & 0xff; |
| 384 | int offset = bucket >> 8; |
| 385 | for (int i = 0; i < num; ++i) { |
| 386 | const DictWord w = kStaticDictionaryWords[offset + i]; |
| 387 | const int l = w.len; |
| 388 | const int n = 1 << kBrotliDictionarySizeBitsByLength[l]; |
| 389 | const int id = w.idx; |
| 390 | if (w.transform == 0 && IsMatch(w, &data[2], max_length - 2)) { |
Lode Vandevenne | 6511d6b | 2015-08-28 16:09:23 +0200 | [diff] [blame] | 391 | if (data[0] == 0xc2) { |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 392 | AddMatch(id + 102 * n, l + 2, l, matches); |
| 393 | found_match = true; |
| 394 | } else if (l + 2 < max_length && data[l + 2] == ' ') { |
| 395 | int t = data[0] == 'e' ? 18 : (data[0] == 's' ? 7 : 13); |
| 396 | AddMatch(id + t * n, l + 3, l, matches); |
| 397 | found_match = true; |
| 398 | } |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 399 | } |
| 400 | } |
| 401 | } |
| 402 | } |
Lode Vandevenne | 17ed258 | 2015-08-10 13:13:58 +0200 | [diff] [blame] | 403 | if (max_length >= 9) { |
| 404 | // Transforms with prefixes " the " and ".com/" |
| 405 | if ((data[0] == ' ' && data[1] == 't' && data[2] == 'h' && |
| 406 | data[3] == 'e' && data[4] == ' ') || |
| 407 | (data[0] == '.' && data[1] == 'c' && data[2] == 'o' && |
| 408 | data[3] == 'm' && data[4] == '/')) { |
| 409 | key = Hash(&data[5]); |
| 410 | bucket = kStaticDictionaryBuckets[key]; |
| 411 | int num = bucket & 0xff; |
| 412 | int offset = bucket >> 8; |
| 413 | for (int i = 0; i < num; ++i) { |
| 414 | const DictWord w = kStaticDictionaryWords[offset + i]; |
| 415 | const int l = w.len; |
| 416 | const int n = 1 << kBrotliDictionarySizeBitsByLength[l]; |
| 417 | const int id = w.idx; |
| 418 | if (w.transform == 0 && IsMatch(w, &data[5], max_length - 5)) { |
| 419 | AddMatch(id + (data[0] == ' ' ? 41 : 72) * n, l + 5, l, matches); |
| 420 | found_match = true; |
| 421 | if (l + 5 < max_length) { |
| 422 | const uint8_t* s = &data[l + 5]; |
| 423 | if (data[0] == ' ') { |
| 424 | if (l + 8 < max_length && |
| 425 | s[0] == ' ' && s[1] == 'o' && s[2] == 'f' && s[3] == ' ') { |
| 426 | AddMatch(id + 62 * n, l + 9, l, matches); |
| 427 | if (l + 12 < max_length && |
| 428 | s[4] == 't' && s[5] == 'h' && s[6] == 'e' && s[7] == ' ') { |
| 429 | AddMatch(id + 73 * n, l + 13, l, matches); |
| 430 | } |
| 431 | } |
Zoltan Szabadka | 6609883 | 2015-06-12 16:45:17 +0200 | [diff] [blame] | 432 | } |
| 433 | } |
| 434 | } |
| 435 | } |
| 436 | } |
| 437 | } |
| 438 | return found_match; |
| 439 | } |
| 440 | |
| 441 | } // namespace brotli |