/* Copyright 2013 Google Inc. All Rights Reserved. Distributed under MIT license. See file LICENSE for detail or copy at https://opensource.org/licenses/MIT */ /* Function to find backward reference copies. */ #include "./enc/backward_references.h" #include "./common/constants.h" #include "./common/dictionary.h" #include <brotli/types.h> #include "./enc/command.h" #include "./enc/dictionary_hash.h" #include "./enc/memory.h" #include "./enc/port.h" #include "./enc/quality.h" #if defined(__cplusplus) || defined(c_plusplus) extern "C" { #endif static BROTLI_INLINE size_t ComputeDistanceCode(size_t distance, size_t max_distance, const int* dist_cache) { if (distance <= max_distance) { size_t distance_plus_3 = distance + 3; size_t offset0 = distance_plus_3 - (size_t)dist_cache[0]; size_t offset1 = distance_plus_3 - (size_t)dist_cache[1]; if (distance == (size_t)dist_cache[0]) { return 0; } else if (distance == (size_t)dist_cache[1]) { return 1; } else if (offset0 < 7) { return (0x9750468 >> (4 * offset0)) & 0xF; } else if (offset1 < 7) { return (0xFDB1ACE >> (4 * offset1)) & 0xF; } else if (distance == (size_t)dist_cache[2]) { return 2; } else if (distance == (size_t)dist_cache[3]) { return 3; } } return distance + BROTLI_NUM_DISTANCE_SHORT_CODES - 1; } #define EXPAND_CAT(a, b) CAT(a, b) #define CAT(a, b) a ## b #define FN(X) EXPAND_CAT(X, HASHER()) #define HASHER() H2 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H3 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H4 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H5 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H6 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H40 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H41 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H42 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #define HASHER() H54 /* NOLINTNEXTLINE(build/include) */ #include "./enc/backward_references_inc.h" #undef HASHER #undef FN #undef CAT #undef EXPAND_CAT void BrotliCreateBackwardReferences(const BrotliDictionary* dictionary, size_t num_bytes, size_t position, const uint8_t* ringbuffer, size_t ringbuffer_mask, const BrotliEncoderParams* params, HasherHandle hasher, int* dist_cache, size_t* last_insert_len, Command* commands, size_t* num_commands, size_t* num_literals) { switch (params->hasher.type) { #define CASE_(N) \ case N: \ CreateBackwardReferencesH ## N(dictionary, \ kStaticDictionaryHash, num_bytes, position, ringbuffer, \ ringbuffer_mask, params, hasher, dist_cache, \ last_insert_len, commands, num_commands, num_literals); \ break; FOR_GENERIC_HASHERS(CASE_) #undef CASE_ default: break; } } #if defined(__cplusplus) || defined(c_plusplus) } /* extern "C" */ #endif