/* 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 "./backward_references.h" #include "../common/constants.h" #include "../common/context.h" #include "../common/dictionary.h" #include "../common/platform.h" #include #include "./command.h" #include "./dictionary_hash.h" #include "./memory.h" #include "./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 EXPORT_FN(X) EXPAND_CAT(X, EXPAND_CAT(PREFIX(), HASHER())) #define PREFIX() N #define HASHER() H2 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H3 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H4 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H5 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H6 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H40 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H41 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H42 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H54 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H35 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H55 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #define HASHER() H65 /* NOLINTNEXTLINE(build/include) */ #include "./backward_references_inc.h" #undef HASHER #undef PREFIX #undef EXPORT_FN #undef FN #undef CAT #undef EXPAND_CAT void BrotliCreateBackwardReferences(size_t num_bytes, size_t position, const uint8_t* ringbuffer, size_t ringbuffer_mask, ContextLut literal_context_lut, const BrotliEncoderParams* params, Hasher* 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: \ CreateBackwardReferencesNH ## N(num_bytes, \ position, ringbuffer, ringbuffer_mask, \ literal_context_lut, params, hasher, dist_cache, \ last_insert_len, commands, num_commands, num_literals); \ return; FOR_GENERIC_HASHERS(CASE_) #undef CASE_ default: break; } } #if defined(__cplusplus) || defined(c_plusplus) } /* extern "C" */ #endif