diff options
Diffstat (limited to '')
| -rw-r--r-- | decoder.h | 33 |
1 files changed, 22 insertions, 11 deletions
@@ -1,5 +1,5 @@ /* Lzlib - A compression library for lzip files - Copyright (C) 2009, 2010 Antonio Diaz Diaz. + Copyright (C) 2009, 2010, 2011 Antonio Diaz Diaz. This library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -25,6 +25,8 @@ Public License. */ +namespace Lzlib { + class Range_decoder : public Circular_buffer { enum { min_available_bytes = 8 }; @@ -51,7 +53,8 @@ public: bool finished() const throw() { return at_stream_end_ && !used_bytes(); } int free_bytes() const throw() { if( at_stream_end_ ) return 0; return Circular_buffer::free_bytes(); } - long long member_position() const throw() { return member_pos; } + long long member_position() const throw() + { return member_pos; } void purge() throw() { at_stream_end_ = true; Circular_buffer::reset(); } void reset() throw() { at_stream_end_ = false; Circular_buffer::reset(); } @@ -211,7 +214,8 @@ public: uint8_t decode_matched( Range_decoder & range_decoder, const uint8_t prev_byte, const uint8_t match_byte ) - { return range_decoder.decode_matched( bm_literal[lstate(prev_byte)], match_byte ); } + { return range_decoder.decode_matched( bm_literal[lstate(prev_byte)], + match_byte ); } }; @@ -219,9 +223,9 @@ class LZ_decoder : public Circular_buffer { enum { min_free_bytes = max_match_len }; long long partial_data_pos; - const int member_version; const int dictionary_size; uint32_t crc_; + const int member_version; bool member_finished_; bool verify_trailer_pending; unsigned int rep0; // rep[0-3] latest four distances @@ -237,7 +241,7 @@ class LZ_decoder : public Circular_buffer 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]; + Bit_model bm_dis[modeled_distances-end_dis_model+1]; Bit_model bm_align[dis_align_size]; Range_decoder & range_decoder; @@ -245,6 +249,14 @@ class LZ_decoder : public Circular_buffer Len_decoder rep_match_len_decoder; Literal_decoder literal_decoder; + bool verify_trailer(); + + uint8_t get_prev_byte() const throw() + { + const int i = ( ( put > 0 ) ? put : buffer_size ) - 1; + return buffer[i]; + } + uint8_t get_byte( const int distance ) const throw() { int i = put - distance - 1; @@ -278,16 +290,14 @@ class LZ_decoder : public Circular_buffer } } - bool verify_trailer(); - public: LZ_decoder( const File_header & header, Range_decoder & rdec ) : Circular_buffer( std::max( 65536, header.dictionary_size() ) + min_free_bytes ), partial_data_pos( 0 ), - member_version( header.version() ), dictionary_size( header.dictionary_size() ), crc_( 0xFFFFFFFFU ), + member_version( header.version() ), member_finished_( false ), verify_trailer_pending( false ), rep0( 0 ), @@ -301,12 +311,13 @@ public: { return free_bytes() >= min_free_bytes; } uint32_t crc() const throw() { return crc_ ^ 0xFFFFFFFFU; } - int decode_member(); bool member_finished() const throw() { return ( member_finished_ && !used_bytes() ); } - long long member_position() const throw() - { return range_decoder.member_position(); } long long data_position() const throw() { return partial_data_pos + put; } + + int decode_member(); }; + +} // end namespace Lzlib |