1 /* Copyright 2015 Google Inc. All Rights Reserved. 2 3 Distributed under MIT license. 4 See file LICENSE for detail or copy at https://opensource.org/licenses/MIT 5 */ 6 7 /* Function for fast encoding of an input fragment, independently from the input 8 history. This function uses one-pass processing: when we find a backward 9 match, we immediately emit the corresponding command and literal codes to 10 the bit stream. */ 11 12 #ifndef BROTLI_ENC_COMPRESS_FRAGMENT_H_ 13 #define BROTLI_ENC_COMPRESS_FRAGMENT_H_ 14 15 #include "../common/platform.h" 16 #include <brotli/types.h> 17 #include "./memory.h" 18 19 #if defined(__cplusplus) || defined(c_plusplus) 20 extern "C" { 21 #endif 22 23 /* Compresses "input" string to the "*storage" buffer as one or more complete 24 meta-blocks, and updates the "*storage_ix" bit position. 25 26 If "is_last" is 1, emits an additional empty last meta-block. 27 28 "cmd_depth" and "cmd_bits" contain the command and distance prefix codes 29 (see comment in encode.h) used for the encoding of this input fragment. 30 If "is_last" is 0, they are updated to reflect the statistics 31 of this input fragment, to be used for the encoding of the next fragment. 32 33 "*cmd_code_numbits" is the number of bits of the compressed representation 34 of the command and distance prefix codes, and "cmd_code" is an array of 35 at least "(*cmd_code_numbits + 7) >> 3" size that contains the compressed 36 command and distance prefix codes. If "is_last" is 0, these are also 37 updated to represent the updated "cmd_depth" and "cmd_bits". 38 39 REQUIRES: "input_size" is greater than zero, or "is_last" is 1. 40 REQUIRES: "input_size" is less or equal to maximal metablock size (1 << 24). 41 REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero. 42 REQUIRES: "table_size" is an odd (9, 11, 13, 15) power of two 43 OUTPUT: maximal copy distance <= |input_size| 44 OUTPUT: maximal copy distance <= BROTLI_MAX_BACKWARD_LIMIT(18) */ 45 BROTLI_INTERNAL void BrotliCompressFragmentFast(MemoryManager* m, 46 const uint8_t* input, 47 size_t input_size, 48 BROTLI_BOOL is_last, 49 int* table, size_t table_size, 50 uint8_t cmd_depth[128], 51 uint16_t cmd_bits[128], 52 size_t* cmd_code_numbits, 53 uint8_t* cmd_code, 54 size_t* storage_ix, 55 uint8_t* storage); 56 57 #if defined(__cplusplus) || defined(c_plusplus) 58 } /* extern "C" */ 59 #endif 60 61 #endif /* BROTLI_ENC_COMPRESS_FRAGMENT_H_ */ 62