/* Copyright 2013 Google Inc. All Rights Reserved. | |
Distributed under MIT license. | |
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT | |
*/ | |
#include "./static_dict.h" | |
#include "../common/dictionary.h" | |
#include "./find_match_length.h" | |
#include "./port.h" | |
#include "./static_dict_lut.h" | |
#if defined(__cplusplus) || defined(c_plusplus) | |
extern "C" { | |
#endif | |
static const uint8_t kUppercaseFirst = 10; | |
static const uint8_t kOmitLastNTransforms[10] = { | |
0, 12, 27, 23, 42, 63, 56, 48, 59, 64, | |
}; | |
static BROTLI_INLINE uint32_t Hash(const uint8_t *data) { | |
uint32_t h = BROTLI_UNALIGNED_LOAD32(data) * kDictHashMul32; | |
/* The higher bits contain more mixture from the multiplication, | |
so we take our results from there. */ | |
return h >> (32 - kDictNumBits); | |
} | |
static BROTLI_INLINE void AddMatch(size_t distance, size_t len, size_t len_code, | |
uint32_t* matches) { | |
uint32_t match = (uint32_t)((distance << 5) + len_code); | |
matches[len] = BROTLI_MIN(uint32_t, matches[len], match); | |
} | |
static BROTLI_INLINE size_t DictMatchLength(const uint8_t* data, | |
size_t id, | |
size_t len, | |
size_t maxlen) { | |
const size_t offset = kBrotliDictionaryOffsetsByLength[len] + len * id; | |
return FindMatchLengthWithLimit(&kBrotliDictionary[offset], data, | |
BROTLI_MIN(size_t, len, maxlen)); | |
} | |
static BROTLI_INLINE BROTLI_BOOL IsMatch( | |
DictWord w, const uint8_t* data, size_t max_length) { | |
if (w.len > max_length) { | |
return BROTLI_FALSE; | |
} else { | |
const size_t offset = kBrotliDictionaryOffsetsByLength[w.len] + | |
(size_t)w.len * (size_t)w.idx; | |
const uint8_t* dict = &kBrotliDictionary[offset]; | |
if (w.transform == 0) { | |
/* Match against base dictionary word. */ | |
return | |
TO_BROTLI_BOOL(FindMatchLengthWithLimit(dict, data, w.len) == w.len); | |
} else if (w.transform == 10) { | |
/* Match against uppercase first transform. | |
Note that there are only ASCII uppercase words in the lookup table. */ | |
return TO_BROTLI_BOOL(dict[0] >= 'a' && dict[0] <= 'z' && | |
(dict[0] ^ 32) == data[0] && | |
FindMatchLengthWithLimit(&dict[1], &data[1], w.len - 1u) == | |
w.len - 1u); | |
} else { | |
/* Match against uppercase all transform. | |
Note that there are only ASCII uppercase words in the lookup table. */ | |
size_t i; | |
for (i = 0; i < w.len; ++i) { | |
if (dict[i] >= 'a' && dict[i] <= 'z') { | |
if ((dict[i] ^ 32) != data[i]) return BROTLI_FALSE; | |
} else { | |
if (dict[i] != data[i]) return BROTLI_FALSE; | |
} | |
} | |
return BROTLI_TRUE; | |
} | |
} | |
} | |
BROTLI_BOOL BrotliFindAllStaticDictionaryMatches( | |
const uint8_t* data, size_t min_length, size_t max_length, | |
uint32_t* matches) { | |
BROTLI_BOOL has_found_match = BROTLI_FALSE; | |
{ | |
size_t offset = kStaticDictionaryBuckets[Hash(data)]; | |
BROTLI_BOOL end = !offset; | |
while (!end) { | |
DictWord w = kStaticDictionaryWords[offset++]; | |
const size_t l = w.len & 0x7F; | |
const size_t n = (size_t)1 << kBrotliDictionarySizeBitsByLength[l]; | |
const size_t id = w.idx; | |
end = !!(w.len & 0x80); | |
w.len = (uint8_t)l; | |
if (w.transform == 0) { | |
const size_t matchlen = DictMatchLength(data, id, l, max_length); | |
const uint8_t* s; | |
size_t minlen; | |
size_t maxlen; | |
size_t len; | |
/* Transform "" + kIdentity + "" */ | |
if (matchlen == l) { | |
AddMatch(id, l, l, matches); | |
has_found_match = BROTLI_TRUE; | |
} | |
/* Transforms "" + kOmitLast1 + "" and "" + kOmitLast1 + "ing " */ | |
if (matchlen >= l - 1) { | |
AddMatch(id + 12 * n, l - 1, l, matches); | |
if (l + 2 < max_length && | |
data[l - 1] == 'i' && data[l] == 'n' && data[l + 1] == 'g' && | |
data[l + 2] == ' ') { | |
AddMatch(id + 49 * n, l + 3, l, matches); | |
} | |
has_found_match = BROTLI_TRUE; | |
} | |
/* Transform "" + kOmitLastN + "" (N = 2 .. 9) */ | |
minlen = min_length; | |
if (l > 9) minlen = BROTLI_MAX(size_t, minlen, l - 9); | |
maxlen = BROTLI_MIN(size_t, matchlen, l - 2); | |
for (len = minlen; len <= maxlen; ++len) { | |
AddMatch(id + kOmitLastNTransforms[l - len] * n, len, l, matches); | |
has_found_match = BROTLI_TRUE; | |
} | |
if (matchlen < l || l + 6 >= max_length) { | |
continue; | |
} | |
s = &data[l]; | |
/* Transforms "" + kIdentity + <suffix> */ | |
if (s[0] == ' ') { | |
AddMatch(id + n, l + 1, l, matches); | |
if (s[1] == 'a') { | |
if (s[2] == ' ') { | |
AddMatch(id + 28 * n, l + 3, l, matches); | |
} else if (s[2] == 's') { | |
if (s[3] == ' ') AddMatch(id + 46 * n, l + 4, l, matches); | |
} else if (s[2] == 't') { | |
if (s[3] == ' ') AddMatch(id + 60 * n, l + 4, l, matches); | |
} else if (s[2] == 'n') { | |
if (s[3] == 'd' && s[4] == ' ') { | |
AddMatch(id + 10 * n, l + 5, l, matches); | |
} | |
} | |
} else if (s[1] == 'b') { | |
if (s[2] == 'y' && s[3] == ' ') { | |
AddMatch(id + 38 * n, l + 4, l, matches); | |
} | |
} else if (s[1] == 'i') { | |
if (s[2] == 'n') { | |
if (s[3] == ' ') AddMatch(id + 16 * n, l + 4, l, matches); | |
} else if (s[2] == 's') { | |
if (s[3] == ' ') AddMatch(id + 47 * n, l + 4, l, matches); | |
} | |
} else if (s[1] == 'f') { | |
if (s[2] == 'o') { | |
if (s[3] == 'r' && s[4] == ' ') { | |
AddMatch(id + 25 * n, l + 5, l, matches); | |
} | |
} else if (s[2] == 'r') { | |
if (s[3] == 'o' && s[4] == 'm' && s[5] == ' ') { | |
AddMatch(id + 37 * n, l + 6, l, matches); | |
} | |
} | |
} else if (s[1] == 'o') { | |
if (s[2] == 'f') { | |
if (s[3] == ' ') AddMatch(id + 8 * n, l + 4, l, matches); | |
} else if (s[2] == 'n') { | |
if (s[3] == ' ') AddMatch(id + 45 * n, l + 4, l, matches); | |
} | |
} else if (s[1] == 'n') { | |
if (s[2] == 'o' && s[3] == 't' && s[4] == ' ') { | |
AddMatch(id + 80 * n, l + 5, l, matches); | |
} | |
} else if (s[1] == 't') { | |
if (s[2] == 'h') { | |
if (s[3] == 'e') { | |
if (s[4] == ' ') AddMatch(id + 5 * n, l + 5, l, matches); | |
} else if (s[3] == 'a') { | |
if (s[4] == 't' && s[5] == ' ') { | |
AddMatch(id + 29 * n, l + 6, l, matches); | |
} | |
} | |
} else if (s[2] == 'o') { | |
if (s[3] == ' ') AddMatch(id + 17 * n, l + 4, l, matches); | |
} | |
} else if (s[1] == 'w') { | |
if (s[2] == 'i' && s[3] == 't' && s[4] == 'h' && s[5] == ' ') { | |
AddMatch(id + 35 * n, l + 6, l, matches); | |
} | |
} | |
} else if (s[0] == '"') { | |
AddMatch(id + 19 * n, l + 1, l, matches); | |
if (s[1] == '>') { | |
AddMatch(id + 21 * n, l + 2, l, matches); | |
} | |
} else if (s[0] == '.') { | |
AddMatch(id + 20 * n, l + 1, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + 31 * n, l + 2, l, matches); | |
if (s[2] == 'T' && s[3] == 'h') { | |
if (s[4] == 'e') { | |
if (s[5] == ' ') AddMatch(id + 43 * n, l + 6, l, matches); | |
} else if (s[4] == 'i') { | |
if (s[5] == 's' && s[6] == ' ') { | |
AddMatch(id + 75 * n, l + 7, l, matches); | |
} | |
} | |
} | |
} | |
} else if (s[0] == ',') { | |
AddMatch(id + 76 * n, l + 1, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + 14 * n, l + 2, l, matches); | |
} | |
} else if (s[0] == '\n') { | |
AddMatch(id + 22 * n, l + 1, l, matches); | |
if (s[1] == '\t') { | |
AddMatch(id + 50 * n, l + 2, l, matches); | |
} | |
} else if (s[0] == ']') { | |
AddMatch(id + 24 * n, l + 1, l, matches); | |
} else if (s[0] == '\'') { | |
AddMatch(id + 36 * n, l + 1, l, matches); | |
} else if (s[0] == ':') { | |
AddMatch(id + 51 * n, l + 1, l, matches); | |
} else if (s[0] == '(') { | |
AddMatch(id + 57 * n, l + 1, l, matches); | |
} else if (s[0] == '=') { | |
if (s[1] == '"') { | |
AddMatch(id + 70 * n, l + 2, l, matches); | |
} else if (s[1] == '\'') { | |
AddMatch(id + 86 * n, l + 2, l, matches); | |
} | |
} else if (s[0] == 'a') { | |
if (s[1] == 'l' && s[2] == ' ') { | |
AddMatch(id + 84 * n, l + 3, l, matches); | |
} | |
} else if (s[0] == 'e') { | |
if (s[1] == 'd') { | |
if (s[2] == ' ') AddMatch(id + 53 * n, l + 3, l, matches); | |
} else if (s[1] == 'r') { | |
if (s[2] == ' ') AddMatch(id + 82 * n, l + 3, l, matches); | |
} else if (s[1] == 's') { | |
if (s[2] == 't' && s[3] == ' ') { | |
AddMatch(id + 95 * n, l + 4, l, matches); | |
} | |
} | |
} else if (s[0] == 'f') { | |
if (s[1] == 'u' && s[2] == 'l' && s[3] == ' ') { | |
AddMatch(id + 90 * n, l + 4, l, matches); | |
} | |
} else if (s[0] == 'i') { | |
if (s[1] == 'v') { | |
if (s[2] == 'e' && s[3] == ' ') { | |
AddMatch(id + 92 * n, l + 4, l, matches); | |
} | |
} else if (s[1] == 'z') { | |
if (s[2] == 'e' && s[3] == ' ') { | |
AddMatch(id + 100 * n, l + 4, l, matches); | |
} | |
} | |
} else if (s[0] == 'l') { | |
if (s[1] == 'e') { | |
if (s[2] == 's' && s[3] == 's' && s[4] == ' ') { | |
AddMatch(id + 93 * n, l + 5, l, matches); | |
} | |
} else if (s[1] == 'y') { | |
if (s[2] == ' ') AddMatch(id + 61 * n, l + 3, l, matches); | |
} | |
} else if (s[0] == 'o') { | |
if (s[1] == 'u' && s[2] == 's' && s[3] == ' ') { | |
AddMatch(id + 106 * n, l + 4, l, matches); | |
} | |
} | |
} else { | |
/* Set is_all_caps=0 for kUppercaseFirst and | |
is_all_caps=1 otherwise (kUppercaseAll) transform. */ | |
const BROTLI_BOOL is_all_caps = | |
TO_BROTLI_BOOL(w.transform != kUppercaseFirst); | |
const uint8_t* s; | |
if (!IsMatch(w, data, max_length)) { | |
continue; | |
} | |
/* Transform "" + kUppercase{First,All} + "" */ | |
AddMatch(id + (is_all_caps ? 44 : 9) * n, l, l, matches); | |
has_found_match = BROTLI_TRUE; | |
if (l + 1 >= max_length) { | |
continue; | |
} | |
/* Transforms "" + kUppercase{First,All} + <suffix> */ | |
s = &data[l]; | |
if (s[0] == ' ') { | |
AddMatch(id + (is_all_caps ? 68 : 4) * n, l + 1, l, matches); | |
} else if (s[0] == '"') { | |
AddMatch(id + (is_all_caps ? 87 : 66) * n, l + 1, l, matches); | |
if (s[1] == '>') { | |
AddMatch(id + (is_all_caps ? 97 : 69) * n, l + 2, l, matches); | |
} | |
} else if (s[0] == '.') { | |
AddMatch(id + (is_all_caps ? 101 : 79) * n, l + 1, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + (is_all_caps ? 114 : 88) * n, l + 2, l, matches); | |
} | |
} else if (s[0] == ',') { | |
AddMatch(id + (is_all_caps ? 112 : 99) * n, l + 1, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + (is_all_caps ? 107 : 58) * n, l + 2, l, matches); | |
} | |
} else if (s[0] == '\'') { | |
AddMatch(id + (is_all_caps ? 94 : 74) * n, l + 1, l, matches); | |
} else if (s[0] == '(') { | |
AddMatch(id + (is_all_caps ? 113 : 78) * n, l + 1, l, matches); | |
} else if (s[0] == '=') { | |
if (s[1] == '"') { | |
AddMatch(id + (is_all_caps ? 105 : 104) * n, l + 2, l, matches); | |
} else if (s[1] == '\'') { | |
AddMatch(id + (is_all_caps ? 116 : 108) * n, l + 2, l, matches); | |
} | |
} | |
} | |
} | |
} | |
/* Transforms with prefixes " " and "." */ | |
if (max_length >= 5 && (data[0] == ' ' || data[0] == '.')) { | |
BROTLI_BOOL is_space = TO_BROTLI_BOOL(data[0] == ' '); | |
size_t offset = kStaticDictionaryBuckets[Hash(&data[1])]; | |
BROTLI_BOOL end = !offset; | |
while (!end) { | |
DictWord w = kStaticDictionaryWords[offset++]; | |
const size_t l = w.len & 0x7F; | |
const size_t n = (size_t)1 << kBrotliDictionarySizeBitsByLength[l]; | |
const size_t id = w.idx; | |
end = !!(w.len & 0x80); | |
w.len = (uint8_t)l; | |
if (w.transform == 0) { | |
const uint8_t* s; | |
if (!IsMatch(w, &data[1], max_length - 1)) { | |
continue; | |
} | |
/* Transforms " " + kIdentity + "" and "." + kIdentity + "" */ | |
AddMatch(id + (is_space ? 6 : 32) * n, l + 1, l, matches); | |
has_found_match = BROTLI_TRUE; | |
if (l + 2 >= max_length) { | |
continue; | |
} | |
/* Transforms " " + kIdentity + <suffix> and "." + kIdentity + <suffix> | |
*/ | |
s = &data[l + 1]; | |
if (s[0] == ' ') { | |
AddMatch(id + (is_space ? 2 : 77) * n, l + 2, l, matches); | |
} else if (s[0] == '(') { | |
AddMatch(id + (is_space ? 89 : 67) * n, l + 2, l, matches); | |
} else if (is_space) { | |
if (s[0] == ',') { | |
AddMatch(id + 103 * n, l + 2, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + 33 * n, l + 3, l, matches); | |
} | |
} else if (s[0] == '.') { | |
AddMatch(id + 71 * n, l + 2, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + 52 * n, l + 3, l, matches); | |
} | |
} else if (s[0] == '=') { | |
if (s[1] == '"') { | |
AddMatch(id + 81 * n, l + 3, l, matches); | |
} else if (s[1] == '\'') { | |
AddMatch(id + 98 * n, l + 3, l, matches); | |
} | |
} | |
} | |
} else if (is_space) { | |
/* Set is_all_caps=0 for kUppercaseFirst and | |
is_all_caps=1 otherwise (kUppercaseAll) transform. */ | |
const BROTLI_BOOL is_all_caps = | |
TO_BROTLI_BOOL(w.transform != kUppercaseFirst); | |
const uint8_t* s; | |
if (!IsMatch(w, &data[1], max_length - 1)) { | |
continue; | |
} | |
/* Transforms " " + kUppercase{First,All} + "" */ | |
AddMatch(id + (is_all_caps ? 85 : 30) * n, l + 1, l, matches); | |
has_found_match = BROTLI_TRUE; | |
if (l + 2 >= max_length) { | |
continue; | |
} | |
/* Transforms " " + kUppercase{First,All} + <suffix> */ | |
s = &data[l + 1]; | |
if (s[0] == ' ') { | |
AddMatch(id + (is_all_caps ? 83 : 15) * n, l + 2, l, matches); | |
} else if (s[0] == ',') { | |
if (!is_all_caps) { | |
AddMatch(id + 109 * n, l + 2, l, matches); | |
} | |
if (s[1] == ' ') { | |
AddMatch(id + (is_all_caps ? 111 : 65) * n, l + 3, l, matches); | |
} | |
} else if (s[0] == '.') { | |
AddMatch(id + (is_all_caps ? 115 : 96) * n, l + 2, l, matches); | |
if (s[1] == ' ') { | |
AddMatch(id + (is_all_caps ? 117 : 91) * n, l + 3, l, matches); | |
} | |
} else if (s[0] == '=') { | |
if (s[1] == '"') { | |
AddMatch(id + (is_all_caps ? 110 : 118) * n, l + 3, l, matches); | |
} else if (s[1] == '\'') { | |
AddMatch(id + (is_all_caps ? 119 : 120) * n, l + 3, l, matches); | |
} | |
} | |
} | |
} | |
} | |
if (max_length >= 6) { | |
/* Transforms with prefixes "e ", "s ", ", " and "\xc2\xa0" */ | |
if ((data[1] == ' ' && | |
(data[0] == 'e' || data[0] == 's' || data[0] == ',')) || | |
(data[0] == 0xc2 && data[1] == 0xa0)) { | |
size_t offset = kStaticDictionaryBuckets[Hash(&data[2])]; | |
BROTLI_BOOL end = !offset; | |
while (!end) { | |
DictWord w = kStaticDictionaryWords[offset++]; | |
const size_t l = w.len & 0x7F; | |
const size_t n = (size_t)1 << kBrotliDictionarySizeBitsByLength[l]; | |
const size_t id = w.idx; | |
end = !!(w.len & 0x80); | |
w.len = (uint8_t)l; | |
if (w.transform == 0 && IsMatch(w, &data[2], max_length - 2)) { | |
if (data[0] == 0xc2) { | |
AddMatch(id + 102 * n, l + 2, l, matches); | |
has_found_match = BROTLI_TRUE; | |
} else if (l + 2 < max_length && data[l + 2] == ' ') { | |
size_t t = data[0] == 'e' ? 18 : (data[0] == 's' ? 7 : 13); | |
AddMatch(id + t * n, l + 3, l, matches); | |
has_found_match = BROTLI_TRUE; | |
} | |
} | |
} | |
} | |
} | |
if (max_length >= 9) { | |
/* Transforms with prefixes " the " and ".com/" */ | |
if ((data[0] == ' ' && data[1] == 't' && data[2] == 'h' && | |
data[3] == 'e' && data[4] == ' ') || | |
(data[0] == '.' && data[1] == 'c' && data[2] == 'o' && | |
data[3] == 'm' && data[4] == '/')) { | |
size_t offset = kStaticDictionaryBuckets[Hash(&data[5])]; | |
BROTLI_BOOL end = !offset; | |
while (!end) { | |
DictWord w = kStaticDictionaryWords[offset++]; | |
const size_t l = w.len & 0x7F; | |
const size_t n = (size_t)1 << kBrotliDictionarySizeBitsByLength[l]; | |
const size_t id = w.idx; | |
end = !!(w.len & 0x80); | |
w.len = (uint8_t)l; | |
if (w.transform == 0 && IsMatch(w, &data[5], max_length - 5)) { | |
AddMatch(id + (data[0] == ' ' ? 41 : 72) * n, l + 5, l, matches); | |
has_found_match = BROTLI_TRUE; | |
if (l + 5 < max_length) { | |
const uint8_t* s = &data[l + 5]; | |
if (data[0] == ' ') { | |
if (l + 8 < max_length && | |
s[0] == ' ' && s[1] == 'o' && s[2] == 'f' && s[3] == ' ') { | |
AddMatch(id + 62 * n, l + 9, l, matches); | |
if (l + 12 < max_length && | |
s[4] == 't' && s[5] == 'h' && s[6] == 'e' && s[7] == ' ') { | |
AddMatch(id + 73 * n, l + 13, l, matches); | |
} | |
} | |
} | |
} | |
} | |
} | |
} | |
} | |
return has_found_match; | |
} | |
#if defined(__cplusplus) || defined(c_plusplus) | |
} /* extern "C" */ | |
#endif |