diff options
Diffstat (limited to 'decoder.cc')
| -rw-r--r-- | decoder.cc | 93 |
1 files changed, 54 insertions, 39 deletions
@@ -1,4 +1,4 @@ -/* Lzip - A data compressor based on the LZMA algorithm +/* Lzip - Data compressor based on the LZMA algorithm Copyright (C) 2008, 2009, 2010 Antonio Diaz Diaz. This program is free software: you can redistribute it and/or modify @@ -32,18 +32,17 @@ const CRC32 crc32; - bool Range_decoder::read_block() { if( !at_stream_end ) { - stream_pos = readblock( infd_, buffer, buffer_size ); - if( stream_pos != buffer_size && errno ) throw Error( "read error" ); + stream_pos = readblock( infd, buffer, buffer_size ); + if( stream_pos != buffer_size && errno ) throw Error( "Read error" ); at_stream_end = ( stream_pos < buffer_size ); partial_member_pos += pos; pos = 0; } - return !finished(); + return pos < stream_pos; } @@ -53,9 +52,9 @@ void LZ_decoder::flush_data() if( size > 0 ) { crc32.update( crc_, buffer + stream_pos, size ); - if( outfd_ >= 0 && - writeblock( outfd_, buffer + stream_pos, size ) != size ) - throw Error( "write error" ); + if( outfd >= 0 && + writeblock( outfd, buffer + stream_pos, size ) != size ) + throw Error( "Write error" ); if( pos >= buffer_size ) { partial_data_pos += pos; pos = 0; } stream_pos = pos; } @@ -66,7 +65,7 @@ bool LZ_decoder::verify_trailer( const Pretty_print & pp ) const { File_trailer trailer; const int trailer_size = File_trailer::size( member_version ); - const long long member_size = member_position() + trailer_size; + const long long member_size = range_decoder.member_position() + trailer_size; bool error = false; for( int i = 0; i < trailer_size && !error; ++i ) @@ -76,10 +75,10 @@ bool LZ_decoder::verify_trailer( const Pretty_print & pp ) const else { error = true; - if( verbosity >= 0 ) + if( pp.verbosity() >= 0 ) { pp(); - std::fprintf( stderr, "trailer truncated at trailer position %d;" + std::fprintf( stderr, "Trailer truncated at trailer position %d;" " some checks may fail.\n", i ); } for( ; i < trailer_size; ++i ) trailer.data[i] = 0; @@ -89,58 +88,73 @@ bool LZ_decoder::verify_trailer( const Pretty_print & pp ) const if( !range_decoder.code_is_zero() ) { error = true; - if( verbosity >= 0 ) - { - pp(); - std::fprintf( stderr, "range_decoder final code is not zero.\n" ); - } + pp( "Range decoder final code is not zero" ); } if( trailer.data_crc() != crc() ) { error = true; - if( verbosity >= 0 ) + if( pp.verbosity() >= 0 ) { pp(); - std::fprintf( stderr, "crc mismatch; trailer says %08X, data crc is %08X.\n", + std::fprintf( stderr, "CRC mismatch; trailer says %08X, data CRC is %08X.\n", (unsigned int)trailer.data_crc(), (unsigned int)crc() ); } } if( trailer.data_size() != data_position() ) { error = true; - if( verbosity >= 0 ) + if( pp.verbosity() >= 0 ) { pp(); - std::fprintf( stderr, "data size mismatch; trailer says %lld, data size is %lld (0x%llX).\n", + std::fprintf( stderr, "Data size mismatch; trailer says %lld, data size is %lld (0x%llX).\n", trailer.data_size(), data_position(), data_position() ); } } if( trailer.member_size() != member_size ) { error = true; - if( verbosity >= 0 ) + if( pp.verbosity() >= 0 ) { pp(); - std::fprintf( stderr, "member size mismatch; trailer says %lld, member size is %lld (0x%llX).\n", + std::fprintf( stderr, "Member size mismatch; trailer says %lld, member size is %lld (0x%llX).\n", trailer.member_size(), member_size, member_size ); } } - if( !error && verbosity >= 3 ) - std::fprintf( stderr, "data crc %08X, data size %9lld, member size %8lld. ", + if( !error && pp.verbosity() >= 4 && data_position() > 0 && member_size > 0 ) + std::fprintf( stderr, "%6.3f:1, %6.3f bits/byte, %5.2f%% saved. ", + (double)data_position() / member_size, + ( 8.0 * member_size ) / data_position(), + 100.0 * ( 1.0 - ( (double)member_size / data_position() ) ) ); + if( !error && pp.verbosity() >= 3 ) + std::fprintf( stderr, "data CRC %08X, data size %9lld, member size %8lld. ", (unsigned int)trailer.data_crc(), trailer.data_size(), trailer.member_size() ); return !error; } - // Return value: 0 = OK, 1 = decoder error, 2 = unexpected EOF, - // 3 = trailer error, 4 = unknown marker found. +// Return value: 0 = OK, 1 = decoder error, 2 = unexpected EOF, +// 3 = trailer error, 4 = unknown marker found. int LZ_decoder::decode_member( const Pretty_print & pp ) { + Bit_model bm_match[State::states][pos_states]; + Bit_model bm_rep[State::states]; + Bit_model bm_rep0[State::states]; + Bit_model bm_rep1[State::states]; + Bit_model bm_rep2[State::states]; + Bit_model bm_len[State::states][pos_states]; + Bit_model bm_dis_slot[max_dis_states][1<<dis_slot_bits]; + Bit_model bm_dis[modeled_distances-end_dis_model+1]; + Bit_model bm_align[dis_align_size]; + unsigned int rep0 = 0; // rep[0-3] latest four distances unsigned int rep1 = 0; // used for efficient coding of unsigned int rep2 = 0; // repeated distances unsigned int rep3 = 0; + + Len_decoder len_decoder; + Len_decoder rep_match_len_decoder; + Literal_decoder literal_decoder; State state; range_decoder.load(); @@ -150,7 +164,7 @@ int LZ_decoder::decode_member( const Pretty_print & pp ) const int pos_state = data_position() & pos_state_mask; if( range_decoder.decode_bit( bm_match[state()][pos_state] ) == 0 ) { - const uint8_t prev_byte = get_byte( 0 ); + const uint8_t prev_byte = get_prev_byte(); if( state.is_char() ) put_byte( literal_decoder.decode( range_decoder, prev_byte ) ); else @@ -164,12 +178,7 @@ int LZ_decoder::decode_member( const Pretty_print & pp ) if( range_decoder.decode_bit( bm_rep[state()] ) == 1 ) { len = 0; - if( range_decoder.decode_bit( bm_rep0[state()] ) == 0 ) - { - if( range_decoder.decode_bit( bm_len[state()][pos_state] ) == 0 ) - { len = 1; state.set_short_rep(); } - } - else + if( range_decoder.decode_bit( bm_rep0[state()] ) == 1 ) { unsigned int distance; if( range_decoder.decode_bit( bm_rep1[state()] ) == 0 ) @@ -184,15 +193,20 @@ int LZ_decoder::decode_member( const Pretty_print & pp ) rep1 = rep0; rep0 = distance; } + else + { + if( range_decoder.decode_bit( bm_len[state()][pos_state] ) == 0 ) + { state.set_short_rep(); len = 1; } + } if( len == 0 ) { - len = min_match_len + rep_match_len_decoder.decode( range_decoder, pos_state ); state.set_rep(); + len = min_match_len + rep_match_len_decoder.decode( range_decoder, pos_state ); } } else { - unsigned int rep0_saved = rep0; + const unsigned int rep0_saved = rep0; len = min_match_len + len_decoder.decode( range_decoder, pos_state ); const int dis_slot = range_decoder.decode_tree( bm_dis_slot[get_dis_state(len)], dis_slot_bits ); if( dis_slot < start_dis_model ) rep0 = dis_slot; @@ -219,19 +233,20 @@ int LZ_decoder::decode_member( const Pretty_print & pp ) { range_decoder.load(); continue; } - if( verbosity >= 0 ) + if( pp.verbosity() >= 0 ) { pp(); - std::fprintf( stderr, "unsupported marker code `%d'.\n", len ); + std::fprintf( stderr, "Unsupported marker code `%d'.\n", len ); } return 4; } - if( rep0 >= (unsigned int)dictionary_size ) - { flush_data(); return 1; } } } rep3 = rep2; rep2 = rep1; rep1 = rep0_saved; state.set_match(); + if( rep0 >= (unsigned int)dictionary_size || + ( rep0 >= (unsigned int)pos && !partial_data_pos ) ) + { flush_data(); return 1; } } copy_block( rep0, len ); } |