diff options
Diffstat (limited to 'lzip.h')
| -rw-r--r-- | lzip.h | 40 |
1 files changed, 26 insertions, 14 deletions
@@ -1,5 +1,5 @@ /* Lzip - LZMA lossless data compressor - Copyright (C) 2008-2014 Antonio Diaz Diaz. + Copyright (C) 2008-2015 Antonio Diaz Diaz. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -40,7 +40,7 @@ public: enum { min_dictionary_bits = 12, - min_dictionary_size = 1 << min_dictionary_bits, // >= modeled_distances + min_dictionary_size = 1 << min_dictionary_bits, /* >= modeled_distances */ max_dictionary_bits = 29, max_dictionary_size = 1 << max_dictionary_bits, literal_context_bits = 3, @@ -52,7 +52,7 @@ enum { dis_slot_bits = 6, start_dis_model = 4, end_dis_model = 14, - modeled_distances = 1 << (end_dis_model / 2), // 128 + modeled_distances = 1 << (end_dis_model / 2), /* 128 */ dis_align_bits = 4, dis_align_size = 1 << dis_align_bits, @@ -64,8 +64,8 @@ enum { len_high_symbols = 1 << len_high_bits, max_len_symbols = len_low_symbols + len_mid_symbols + len_high_symbols, - min_match_len = 2, // must be 2 - max_match_len = min_match_len + max_len_symbols - 1, // 273 + min_match_len = 2, /* must be 2 */ + max_match_len = min_match_len + max_len_symbols - 1, /* 273 */ min_match_len_limit = 5 }; inline int get_len_state( const int len ) @@ -82,7 +82,10 @@ enum { bit_model_move_bits = 5, struct Bit_model { int probability; - Bit_model() : probability( bit_model_total / 2 ) {} + void reset() { probability = bit_model_total / 2; } + void reset( const int size ) + { for( int i = 0; i < size; ++i ) this[i].reset(); } + Bit_model() { reset(); } }; struct Len_model @@ -92,6 +95,15 @@ struct Len_model Bit_model bm_low[pos_states][len_low_symbols]; Bit_model bm_mid[pos_states][len_mid_symbols]; Bit_model bm_high[len_high_symbols]; + + void reset() + { + choice1.reset(); + choice2.reset(); + bm_low[0][0].reset( pos_states * len_low_symbols ); + bm_mid[0][0].reset( pos_states * len_mid_symbols ); + bm_high[0].reset( len_high_symbols ); + } }; @@ -173,9 +185,9 @@ const uint8_t magic_string[4] = { 0x4C, 0x5A, 0x49, 0x50 }; // "LZIP" struct File_header { - uint8_t data[6]; // 0-3 magic bytes - // 4 version - // 5 coded_dict_size + uint8_t data[6]; /* 0-3 magic bytes */ + /* 4 version */ + /* 5 coded_dict_size */ enum { size = 6 }; void set_magic() { std::memcpy( data, magic_string, 4 ); data[4] = 1; } @@ -201,9 +213,9 @@ struct File_header if( sz > min_dictionary_size ) { const unsigned base_size = 1 << data[5]; - const unsigned wedge = base_size / 16; + const unsigned fraction = base_size / 16; for( int i = 7; i >= 1; --i ) - if( base_size - ( i * wedge ) >= sz ) + if( base_size - ( i * fraction ) >= sz ) { data[5] |= ( i << 5 ); break; } } return true; @@ -215,9 +227,9 @@ struct File_header struct File_trailer { - uint8_t data[20]; // 0-3 CRC32 of the uncompressed data - // 4-11 size of the uncompressed data - // 12-19 member size including header and trailer + uint8_t data[20]; /* 0-3 CRC32 of the uncompressed data */ + /* 4-11 size of the uncompressed data */ + /* 12-19 member size including header and trailer */ static int size( const int version = 1 ) { return ( ( version >= 1 ) ? 20 : 12 ); } |