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 two-pass processing: in the first pass we save 9 the found backward matches and literal bytes into a buffer, and in the 10 second pass we emit them into the bit stream using prefix codes built based 11 on the actual command and literal byte histograms. */ 12 13 #ifndef BROTLI_ENC_COMPRESS_FRAGMENT_TWO_PASS_H_ 14 #define BROTLI_ENC_COMPRESS_FRAGMENT_TWO_PASS_H_ 15 16 #include "../common/platform.h" 17 #include <brotli/types.h> 18 #include "./memory.h" 19 20 #if defined(__cplusplus) || defined(c_plusplus) 21 extern "C" { 22 #endif 23 24 static const size_t kCompressFragmentTwoPassBlockSize = 1 << 17; 25 26 /* Compresses "input" string to the "*storage" buffer as one or more complete 27 meta-blocks, and updates the "*storage_ix" bit position. 28 29 If "is_last" is 1, emits an additional empty last meta-block. 30 31 REQUIRES: "input_size" is greater than zero, or "is_last" is 1. 32 REQUIRES: "input_size" is less or equal to maximal metablock size (1 << 24). 33 REQUIRES: "command_buf" and "literal_buf" point to at least 34 kCompressFragmentTwoPassBlockSize long arrays. 35 REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero. 36 REQUIRES: "table_size" is a power of two 37 OUTPUT: maximal copy distance <= |input_size| 38 OUTPUT: maximal copy distance <= BROTLI_MAX_BACKWARD_LIMIT(18) */ 39 BROTLI_INTERNAL void BrotliCompressFragmentTwoPass(MemoryManager* m, 40 const uint8_t* input, 41 size_t input_size, 42 BROTLI_BOOL is_last, 43 uint32_t* command_buf, 44 uint8_t* literal_buf, 45 int* table, 46 size_t table_size, 47 size_t* storage_ix, 48 uint8_t* storage); 49 50 #if defined(__cplusplus) || defined(c_plusplus) 51 } /* extern "C" */ 52 #endif 53 54 #endif /* BROTLI_ENC_COMPRESS_FRAGMENT_TWO_PASS_H_ */ 55