mirror of
https://github.com/google/brotli.git
synced 2024-11-22 19:50:06 +00:00
6ece1d8791
* Move files & update paths * Rename build to scripts. * Fix paths * Fix script.
483 lines
18 KiB
C
483 lines
18 KiB
C
/* Copyright 2013 Google Inc. All Rights Reserved.
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Distributed under MIT license.
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See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
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*/
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#include "./static_dict.h"
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#include "../common/dictionary.h"
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#include "./find_match_length.h"
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#include "./port.h"
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#include "./static_dict_lut.h"
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#if defined(__cplusplus) || defined(c_plusplus)
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extern "C" {
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#endif
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static const uint8_t kUppercaseFirst = 10;
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static const uint8_t kOmitLastNTransforms[10] = {
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0, 12, 27, 23, 42, 63, 56, 48, 59, 64,
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};
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static BROTLI_INLINE uint32_t Hash(const uint8_t *data) {
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uint32_t h = BROTLI_UNALIGNED_LOAD32(data) * kDictHashMul32;
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/* The higher bits contain more mixture from the multiplication,
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so we take our results from there. */
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return h >> (32 - kDictNumBits);
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}
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static BROTLI_INLINE void AddMatch(size_t distance, size_t len, size_t len_code,
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uint32_t* matches) {
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uint32_t match = (uint32_t)((distance << 5) + len_code);
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matches[len] = BROTLI_MIN(uint32_t, matches[len], match);
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}
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static BROTLI_INLINE size_t DictMatchLength(const BrotliDictionary* dictionary,
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const uint8_t* data,
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size_t id,
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size_t len,
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size_t maxlen) {
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const size_t offset = dictionary->offsets_by_length[len] + len * id;
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return FindMatchLengthWithLimit(&dictionary->data[offset], data,
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BROTLI_MIN(size_t, len, maxlen));
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}
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static BROTLI_INLINE BROTLI_BOOL IsMatch(const BrotliDictionary* dictionary,
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DictWord w, const uint8_t* data, size_t max_length) {
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if (w.len > max_length) {
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return BROTLI_FALSE;
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} else {
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const size_t offset = dictionary->offsets_by_length[w.len] +
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(size_t)w.len * (size_t)w.idx;
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const uint8_t* dict = &dictionary->data[offset];
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if (w.transform == 0) {
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/* Match against base dictionary word. */
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return
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TO_BROTLI_BOOL(FindMatchLengthWithLimit(dict, data, w.len) == w.len);
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} else if (w.transform == 10) {
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/* Match against uppercase first transform.
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Note that there are only ASCII uppercase words in the lookup table. */
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return TO_BROTLI_BOOL(dict[0] >= 'a' && dict[0] <= 'z' &&
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(dict[0] ^ 32) == data[0] &&
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FindMatchLengthWithLimit(&dict[1], &data[1], w.len - 1u) ==
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w.len - 1u);
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} else {
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/* Match against uppercase all transform.
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Note that there are only ASCII uppercase words in the lookup table. */
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size_t i;
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for (i = 0; i < w.len; ++i) {
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if (dict[i] >= 'a' && dict[i] <= 'z') {
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if ((dict[i] ^ 32) != data[i]) return BROTLI_FALSE;
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} else {
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if (dict[i] != data[i]) return BROTLI_FALSE;
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}
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}
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return BROTLI_TRUE;
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}
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}
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}
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BROTLI_BOOL BrotliFindAllStaticDictionaryMatches(
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const BrotliDictionary* dictionary, const uint8_t* data, size_t min_length,
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size_t max_length, uint32_t* matches) {
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BROTLI_BOOL has_found_match = BROTLI_FALSE;
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{
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size_t offset = kStaticDictionaryBuckets[Hash(data)];
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BROTLI_BOOL end = !offset;
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while (!end) {
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DictWord w = kStaticDictionaryWords[offset++];
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const size_t l = w.len & 0x1F;
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const size_t n = (size_t)1 << dictionary->size_bits_by_length[l];
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const size_t id = w.idx;
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end = !!(w.len & 0x80);
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w.len = (uint8_t)l;
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if (w.transform == 0) {
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const size_t matchlen =
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DictMatchLength(dictionary, data, id, l, max_length);
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const uint8_t* s;
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size_t minlen;
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size_t maxlen;
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size_t len;
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/* Transform "" + kIdentity + "" */
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if (matchlen == l) {
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AddMatch(id, l, l, matches);
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has_found_match = BROTLI_TRUE;
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}
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/* Transforms "" + kOmitLast1 + "" and "" + kOmitLast1 + "ing " */
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if (matchlen >= l - 1) {
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AddMatch(id + 12 * n, l - 1, l, matches);
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if (l + 2 < max_length &&
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data[l - 1] == 'i' && data[l] == 'n' && data[l + 1] == 'g' &&
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data[l + 2] == ' ') {
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AddMatch(id + 49 * n, l + 3, l, matches);
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}
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has_found_match = BROTLI_TRUE;
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}
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/* Transform "" + kOmitLastN + "" (N = 2 .. 9) */
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minlen = min_length;
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if (l > 9) minlen = BROTLI_MAX(size_t, minlen, l - 9);
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maxlen = BROTLI_MIN(size_t, matchlen, l - 2);
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for (len = minlen; len <= maxlen; ++len) {
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AddMatch(id + kOmitLastNTransforms[l - len] * n, len, l, matches);
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has_found_match = BROTLI_TRUE;
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}
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if (matchlen < l || l + 6 >= max_length) {
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continue;
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}
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s = &data[l];
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/* Transforms "" + kIdentity + <suffix> */
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if (s[0] == ' ') {
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AddMatch(id + n, l + 1, l, matches);
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if (s[1] == 'a') {
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if (s[2] == ' ') {
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AddMatch(id + 28 * n, l + 3, l, matches);
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} else if (s[2] == 's') {
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if (s[3] == ' ') AddMatch(id + 46 * n, l + 4, l, matches);
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} else if (s[2] == 't') {
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if (s[3] == ' ') AddMatch(id + 60 * n, l + 4, l, matches);
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} else if (s[2] == 'n') {
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if (s[3] == 'd' && s[4] == ' ') {
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AddMatch(id + 10 * n, l + 5, l, matches);
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}
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}
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} else if (s[1] == 'b') {
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if (s[2] == 'y' && s[3] == ' ') {
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AddMatch(id + 38 * n, l + 4, l, matches);
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}
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} else if (s[1] == 'i') {
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if (s[2] == 'n') {
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if (s[3] == ' ') AddMatch(id + 16 * n, l + 4, l, matches);
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} else if (s[2] == 's') {
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if (s[3] == ' ') AddMatch(id + 47 * n, l + 4, l, matches);
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}
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} else if (s[1] == 'f') {
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if (s[2] == 'o') {
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if (s[3] == 'r' && s[4] == ' ') {
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AddMatch(id + 25 * n, l + 5, l, matches);
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}
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} else if (s[2] == 'r') {
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if (s[3] == 'o' && s[4] == 'm' && s[5] == ' ') {
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AddMatch(id + 37 * n, l + 6, l, matches);
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}
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}
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} else if (s[1] == 'o') {
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if (s[2] == 'f') {
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if (s[3] == ' ') AddMatch(id + 8 * n, l + 4, l, matches);
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} else if (s[2] == 'n') {
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if (s[3] == ' ') AddMatch(id + 45 * n, l + 4, l, matches);
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}
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} else if (s[1] == 'n') {
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if (s[2] == 'o' && s[3] == 't' && s[4] == ' ') {
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AddMatch(id + 80 * n, l + 5, l, matches);
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}
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} else if (s[1] == 't') {
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if (s[2] == 'h') {
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if (s[3] == 'e') {
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if (s[4] == ' ') AddMatch(id + 5 * n, l + 5, l, matches);
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} else if (s[3] == 'a') {
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if (s[4] == 't' && s[5] == ' ') {
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AddMatch(id + 29 * n, l + 6, l, matches);
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}
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}
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} else if (s[2] == 'o') {
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if (s[3] == ' ') AddMatch(id + 17 * n, l + 4, l, matches);
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}
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} else if (s[1] == 'w') {
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if (s[2] == 'i' && s[3] == 't' && s[4] == 'h' && s[5] == ' ') {
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AddMatch(id + 35 * n, l + 6, l, matches);
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}
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}
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} else if (s[0] == '"') {
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AddMatch(id + 19 * n, l + 1, l, matches);
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if (s[1] == '>') {
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AddMatch(id + 21 * n, l + 2, l, matches);
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}
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} else if (s[0] == '.') {
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AddMatch(id + 20 * n, l + 1, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + 31 * n, l + 2, l, matches);
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if (s[2] == 'T' && s[3] == 'h') {
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if (s[4] == 'e') {
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if (s[5] == ' ') AddMatch(id + 43 * n, l + 6, l, matches);
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} else if (s[4] == 'i') {
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if (s[5] == 's' && s[6] == ' ') {
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AddMatch(id + 75 * n, l + 7, l, matches);
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}
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}
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}
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}
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} else if (s[0] == ',') {
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AddMatch(id + 76 * n, l + 1, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + 14 * n, l + 2, l, matches);
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}
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} else if (s[0] == '\n') {
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AddMatch(id + 22 * n, l + 1, l, matches);
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if (s[1] == '\t') {
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AddMatch(id + 50 * n, l + 2, l, matches);
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}
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} else if (s[0] == ']') {
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AddMatch(id + 24 * n, l + 1, l, matches);
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} else if (s[0] == '\'') {
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AddMatch(id + 36 * n, l + 1, l, matches);
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} else if (s[0] == ':') {
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AddMatch(id + 51 * n, l + 1, l, matches);
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} else if (s[0] == '(') {
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AddMatch(id + 57 * n, l + 1, l, matches);
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} else if (s[0] == '=') {
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if (s[1] == '"') {
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AddMatch(id + 70 * n, l + 2, l, matches);
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} else if (s[1] == '\'') {
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AddMatch(id + 86 * n, l + 2, l, matches);
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}
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} else if (s[0] == 'a') {
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if (s[1] == 'l' && s[2] == ' ') {
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AddMatch(id + 84 * n, l + 3, l, matches);
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}
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} else if (s[0] == 'e') {
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if (s[1] == 'd') {
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if (s[2] == ' ') AddMatch(id + 53 * n, l + 3, l, matches);
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} else if (s[1] == 'r') {
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if (s[2] == ' ') AddMatch(id + 82 * n, l + 3, l, matches);
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} else if (s[1] == 's') {
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if (s[2] == 't' && s[3] == ' ') {
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AddMatch(id + 95 * n, l + 4, l, matches);
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}
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}
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} else if (s[0] == 'f') {
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if (s[1] == 'u' && s[2] == 'l' && s[3] == ' ') {
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AddMatch(id + 90 * n, l + 4, l, matches);
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}
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} else if (s[0] == 'i') {
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if (s[1] == 'v') {
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if (s[2] == 'e' && s[3] == ' ') {
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AddMatch(id + 92 * n, l + 4, l, matches);
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}
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} else if (s[1] == 'z') {
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if (s[2] == 'e' && s[3] == ' ') {
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AddMatch(id + 100 * n, l + 4, l, matches);
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}
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}
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} else if (s[0] == 'l') {
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if (s[1] == 'e') {
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if (s[2] == 's' && s[3] == 's' && s[4] == ' ') {
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AddMatch(id + 93 * n, l + 5, l, matches);
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}
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} else if (s[1] == 'y') {
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if (s[2] == ' ') AddMatch(id + 61 * n, l + 3, l, matches);
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}
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} else if (s[0] == 'o') {
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if (s[1] == 'u' && s[2] == 's' && s[3] == ' ') {
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AddMatch(id + 106 * n, l + 4, l, matches);
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}
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}
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} else {
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/* Set is_all_caps=0 for kUppercaseFirst and
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is_all_caps=1 otherwise (kUppercaseAll) transform. */
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const BROTLI_BOOL is_all_caps =
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TO_BROTLI_BOOL(w.transform != kUppercaseFirst);
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const uint8_t* s;
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if (!IsMatch(dictionary, w, data, max_length)) {
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continue;
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}
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/* Transform "" + kUppercase{First,All} + "" */
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AddMatch(id + (is_all_caps ? 44 : 9) * n, l, l, matches);
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has_found_match = BROTLI_TRUE;
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if (l + 1 >= max_length) {
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continue;
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}
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/* Transforms "" + kUppercase{First,All} + <suffix> */
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s = &data[l];
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if (s[0] == ' ') {
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AddMatch(id + (is_all_caps ? 68 : 4) * n, l + 1, l, matches);
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} else if (s[0] == '"') {
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AddMatch(id + (is_all_caps ? 87 : 66) * n, l + 1, l, matches);
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if (s[1] == '>') {
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AddMatch(id + (is_all_caps ? 97 : 69) * n, l + 2, l, matches);
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}
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} else if (s[0] == '.') {
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AddMatch(id + (is_all_caps ? 101 : 79) * n, l + 1, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + (is_all_caps ? 114 : 88) * n, l + 2, l, matches);
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}
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} else if (s[0] == ',') {
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AddMatch(id + (is_all_caps ? 112 : 99) * n, l + 1, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + (is_all_caps ? 107 : 58) * n, l + 2, l, matches);
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}
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} else if (s[0] == '\'') {
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AddMatch(id + (is_all_caps ? 94 : 74) * n, l + 1, l, matches);
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} else if (s[0] == '(') {
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AddMatch(id + (is_all_caps ? 113 : 78) * n, l + 1, l, matches);
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} else if (s[0] == '=') {
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if (s[1] == '"') {
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AddMatch(id + (is_all_caps ? 105 : 104) * n, l + 2, l, matches);
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} else if (s[1] == '\'') {
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AddMatch(id + (is_all_caps ? 116 : 108) * n, l + 2, l, matches);
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}
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}
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}
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}
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}
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/* Transforms with prefixes " " and "." */
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if (max_length >= 5 && (data[0] == ' ' || data[0] == '.')) {
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BROTLI_BOOL is_space = TO_BROTLI_BOOL(data[0] == ' ');
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size_t offset = kStaticDictionaryBuckets[Hash(&data[1])];
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BROTLI_BOOL end = !offset;
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while (!end) {
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DictWord w = kStaticDictionaryWords[offset++];
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const size_t l = w.len & 0x1F;
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const size_t n = (size_t)1 << dictionary->size_bits_by_length[l];
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const size_t id = w.idx;
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end = !!(w.len & 0x80);
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w.len = (uint8_t)l;
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if (w.transform == 0) {
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const uint8_t* s;
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if (!IsMatch(dictionary, w, &data[1], max_length - 1)) {
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continue;
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}
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/* Transforms " " + kIdentity + "" and "." + kIdentity + "" */
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AddMatch(id + (is_space ? 6 : 32) * n, l + 1, l, matches);
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has_found_match = BROTLI_TRUE;
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if (l + 2 >= max_length) {
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continue;
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}
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/* Transforms " " + kIdentity + <suffix> and "." + kIdentity + <suffix>
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*/
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s = &data[l + 1];
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if (s[0] == ' ') {
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AddMatch(id + (is_space ? 2 : 77) * n, l + 2, l, matches);
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} else if (s[0] == '(') {
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AddMatch(id + (is_space ? 89 : 67) * n, l + 2, l, matches);
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} else if (is_space) {
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if (s[0] == ',') {
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AddMatch(id + 103 * n, l + 2, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + 33 * n, l + 3, l, matches);
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}
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} else if (s[0] == '.') {
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AddMatch(id + 71 * n, l + 2, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + 52 * n, l + 3, l, matches);
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}
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} else if (s[0] == '=') {
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if (s[1] == '"') {
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AddMatch(id + 81 * n, l + 3, l, matches);
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} else if (s[1] == '\'') {
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AddMatch(id + 98 * n, l + 3, l, matches);
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}
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}
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}
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} else if (is_space) {
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/* Set is_all_caps=0 for kUppercaseFirst and
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is_all_caps=1 otherwise (kUppercaseAll) transform. */
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const BROTLI_BOOL is_all_caps =
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TO_BROTLI_BOOL(w.transform != kUppercaseFirst);
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const uint8_t* s;
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if (!IsMatch(dictionary, w, &data[1], max_length - 1)) {
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continue;
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}
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/* Transforms " " + kUppercase{First,All} + "" */
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AddMatch(id + (is_all_caps ? 85 : 30) * n, l + 1, l, matches);
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has_found_match = BROTLI_TRUE;
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if (l + 2 >= max_length) {
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continue;
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}
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/* Transforms " " + kUppercase{First,All} + <suffix> */
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s = &data[l + 1];
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if (s[0] == ' ') {
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AddMatch(id + (is_all_caps ? 83 : 15) * n, l + 2, l, matches);
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} else if (s[0] == ',') {
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if (!is_all_caps) {
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AddMatch(id + 109 * n, l + 2, l, matches);
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}
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if (s[1] == ' ') {
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AddMatch(id + (is_all_caps ? 111 : 65) * n, l + 3, l, matches);
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}
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} else if (s[0] == '.') {
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AddMatch(id + (is_all_caps ? 115 : 96) * n, l + 2, l, matches);
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if (s[1] == ' ') {
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AddMatch(id + (is_all_caps ? 117 : 91) * n, l + 3, l, matches);
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}
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} 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 & 0x1F;
|
|
const size_t n = (size_t)1 << dictionary->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, 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 & 0x1F;
|
|
const size_t n = (size_t)1 << dictionary->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, 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
|