1 /////////////////////////////////////////////////////////////////////////////// 2 // 3 /// \file simple_private.h 4 /// \brief Private definitions for so called simple filters 5 // 6 // Author: Lasse Collin 7 // 8 // This file has been put into the public domain. 9 // You can do whatever you want with this file. 10 // 11 /////////////////////////////////////////////////////////////////////////////// 12 13 #ifndef LZMA_SIMPLE_PRIVATE_H 14 #define LZMA_SIMPLE_PRIVATE_H 15 16 #include "simple_coder.h" 17 18 19 typedef struct lzma_simple_s lzma_simple; 20 21 struct lzma_coder_s { 22 /// Next filter in the chain 23 lzma_next_coder next; 24 25 /// True if the next coder in the chain has returned LZMA_STREAM_END. 26 bool end_was_reached; 27 28 /// True if filter() should encode the data; false to decode. 29 /// Currently all simple filters use the same function for encoding 30 /// and decoding, because the difference between encoders and decoders 31 /// is very small. 32 bool is_encoder; 33 34 /// Pointer to filter-specific function, which does 35 /// the actual filtering. 36 size_t (*filter)(lzma_simple *simple, uint32_t now_pos, 37 bool is_encoder, uint8_t *buffer, size_t size); 38 39 /// Pointer to filter-specific data, or NULL if filter doesn't need 40 /// any extra data. 41 lzma_simple *simple; 42 43 /// The lowest 32 bits of the current position in the data. Most 44 /// filters need this to do conversions between absolute and relative 45 /// addresses. 46 uint32_t now_pos; 47 48 /// Size of the memory allocated for the buffer. 49 size_t allocated; 50 51 /// Flushing position in the temporary buffer. buffer[pos] is the 52 /// next byte to be copied to out[]. 53 size_t pos; 54 55 /// buffer[filtered] is the first unfiltered byte. When pos is smaller 56 /// than filtered, there is unflushed filtered data in the buffer. 57 size_t filtered; 58 59 /// Total number of bytes (both filtered and unfiltered) currently 60 /// in the temporary buffer. 61 size_t size; 62 63 /// Temporary buffer 64 uint8_t buffer[]; 65 }; 66 67 68 extern lzma_ret lzma_simple_coder_init(lzma_next_coder *next, 69 const lzma_allocator *allocator, 70 const lzma_filter_info *filters, 71 size_t (*filter)(lzma_simple *simple, uint32_t now_pos, 72 bool is_encoder, uint8_t *buffer, size_t size), 73 size_t simple_size, size_t unfiltered_max, 74 uint32_t alignment, bool is_encoder); 75 76 #endif 77