/* 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 "../common/platform.h"
#include "../common/transform.h"
#include "./encoder_dict.h"
#include "./find_match_length.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
static BROTLI_INLINE uint32_t Hash(const uint8_t* data) {
uint32_t h = BROTLI_UNALIGNED_LOAD32LE(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 BrotliDictionary* dictionary,
const uint8_t* data,
size_t id,
size_t len,
size_t maxlen) {
const size_t offset = dictionary->offsets_by_length[len] + len * id;
return FindMatchLengthWithLimit(&dictionary->data[offset], data,
BROTLI_MIN(size_t, len, maxlen));
}
static BROTLI_INLINE BROTLI_BOOL IsMatch(const BrotliDictionary* dictionary,
DictWord w, const uint8_t* data, size_t max_length) {
if (w.len > max_length) {
return BROTLI_FALSE;
} else {
const size_t offset = dictionary->offsets_by_length[w.len] +
(size_t)w.len * (size_t)w.idx;
const uint8_t* dict = &dictionary->data[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 BrotliEncoderDictionary* dictionary, 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 = dictionary->buckets[Hash(data)];
BROTLI_BOOL end = !offset;
while (!end) {
DictWord w = dictionary->dict_words[offset++];
const size_t l = w.len & 0x1F;
const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[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(dictionary->words, data, id, l, max_length);
const uint8_t* s;
size_t minlen;
size_t maxlen;
size_t len;
/* Transform "" + BROTLI_TRANSFORM_IDENTITY + "" */
if (matchlen == l) {
AddMatch(id, l, l, matches);
has_found_match = BROTLI_TRUE;
}
/* Transforms "" + BROTLI_TRANSFORM_OMIT_LAST_1 + "" and
"" + BROTLI_TRANSFORM_OMIT_LAST_1 + "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 "" + BROTLI_TRANSFORM_OMIT_LAST_# + "" (# = 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) {
size_t cut = l - len;
size_t transform_id = (cut << 2) +
(size_t)((dictionary->cutoffTransforms >> (cut * 6)) & 0x3F);
AddMatch(id + transform_id * n, len, l, matches);
has_found_match = BROTLI_TRUE;
}
if (matchlen < l || l + 6 >= max_length) {
continue;
}
s = &data[l];
/* Transforms "" + BROTLI_TRANSFORM_IDENTITY + <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 BROTLI_TRANSFORM_UPPERCASE_FIRST and
is_all_caps=1 otherwise (BROTLI_TRANSFORM_UPPERCASE_ALL)
transform. */
const BROTLI_BOOL is_all_caps =
TO_BROTLI_BOOL(w.transform != BROTLI_TRANSFORM_UPPERCASE_FIRST);
const uint8_t* s;
if (!IsMatch(dictionary->words, 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 = dictionary->buckets[Hash(&data[1])];
BROTLI_BOOL end = !offset;
while (!end) {
DictWord w = dictionary->dict_words[offset++];
const size_t l = w.len & 0x1F;
const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[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(dictionary->words, w, &data[1], max_length - 1)) {
continue;
}
/* Transforms " " + BROTLI_TRANSFORM_IDENTITY + "" and
"." + BROTLI_TRANSFORM_IDENTITY + "" */
AddMatch(id + (is_space ? 6 : 32) * n, l + 1, l, matches);
has_found_match = BROTLI_TRUE;
if (l + 2 >= max_length) {
continue;
}
/* Transforms " " + BROTLI_TRANSFORM_IDENTITY + <suffix> and
"." + BROTLI_TRANSFORM_IDENTITY + <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 BROTLI_TRANSFORM_UPPERCASE_FIRST and
is_all_caps=1 otherwise (BROTLI_TRANSFORM_UPPERCASE_ALL)
transform. */
const BROTLI_BOOL is_all_caps =
TO_BROTLI_BOOL(w.transform != BROTLI_TRANSFORM_UPPERCASE_FIRST);
const uint8_t* s;
if (!IsMatch(dictionary->words, 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 = dictionary->buckets[Hash(&data[2])];
BROTLI_BOOL end = !offset;
while (!end) {
DictWord w = dictionary->dict_words[offset++];
const size_t l = w.len & 0x1F;
const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[l];
const size_t id = w.idx;
end = !!(w.len & 0x80);
w.len = (uint8_t)l;
if (w.transform == 0 &&
IsMatch(dictionary->words, 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 = dictionary->buckets[Hash(&data[5])];
BROTLI_BOOL end = !offset;
while (!end) {
DictWord w = dictionary->dict_words[offset++];
const size_t l = w.len & 0x1F;
const size_t n = (size_t)1 << dictionary->words->size_bits_by_length[l];
const size_t id = w.idx;
end = !!(w.len & 0x80);
w.len = (uint8_t)l;
if (w.transform == 0 &&
IsMatch(dictionary->words, 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