diff options
Diffstat (limited to '')
-rw-r--r-- | decoder.h | 146 |
1 files changed, 72 insertions, 74 deletions
@@ -1,5 +1,5 @@ /* Lzlib - Compression library for lzip files - Copyright (C) 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz. + Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014 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 @@ -159,6 +159,7 @@ static bool Rd_try_reload( struct Range_decoder * const rdec, const bool force ) for( i = 0; i < 5; ++i ) rdec->code = (rdec->code << 8) | Rd_get_byte( rdec ); rdec->range = 0xFFFFFFFFU; + rdec->code &= rdec->range; /* make sure that first byte is discarded */ } return !rdec->reload_pending; } @@ -233,7 +234,7 @@ static inline int Rd_decode_tree6( struct Range_decoder * const rdec, symbol = ( symbol << 1 ) | Rd_decode_bit( rdec, &bm[symbol] ); symbol = ( symbol << 1 ) | Rd_decode_bit( rdec, &bm[symbol] ); symbol = ( symbol << 1 ) | Rd_decode_bit( rdec, &bm[symbol] ); - return symbol - (1 << 6); + return symbol & 0x3F; } static inline int Rd_decode_tree_reversed( struct Range_decoder * const rdec, @@ -255,9 +256,9 @@ static inline int Rd_decode_tree_reversed4( struct Range_decoder * const rdec, Bit_model bm[] ) { int model = 1; - int symbol = 0; - int bit = Rd_decode_bit( rdec, &bm[model] ); - model = (model << 1) + bit; symbol |= bit; + int symbol = Rd_decode_bit( rdec, &bm[model] ); + int bit; + model = (model << 1) + symbol; bit = Rd_decode_bit( rdec, &bm[model] ); model = (model << 1) + bit; symbol |= (bit << 1); bit = Rd_decode_bit( rdec, &bm[model] ); @@ -271,8 +272,7 @@ static inline int Rd_decode_matched( struct Range_decoder * const rdec, { Bit_model * const bm1 = bm + 0x100; int symbol = 1; - int i; - for( i = 7; i >= 0; --i ) + while( symbol < 0x100 ) { int match_bit, bit; match_byte <<= 1; @@ -286,7 +286,7 @@ static inline int Rd_decode_matched( struct Range_decoder * const rdec, break; } } - return symbol - 0x100; + return symbol & 0xFF; } static inline int Rd_decode_len( struct Range_decoder * const rdec, @@ -309,7 +309,8 @@ struct LZ_decoder { struct Circular_buffer cb; unsigned long long partial_data_pos; - int dictionary_size; + struct Range_decoder * rdec; + unsigned dictionary_size; uint32_t crc; bool member_finished; bool verify_trailer_pending; @@ -330,101 +331,98 @@ struct LZ_decoder Bit_model bm_dis[modeled_distances-end_dis_model]; Bit_model bm_align[dis_align_size]; - struct Range_decoder * rdec; struct Len_model match_len_model; struct Len_model rep_len_model; }; -static inline bool LZd_enough_free_bytes( const struct LZ_decoder * const decoder ) - { return Cb_free_bytes( &decoder->cb ) >= lzd_min_free_bytes; } +static inline bool LZd_enough_free_bytes( const struct LZ_decoder * const d ) + { return Cb_free_bytes( &d->cb ) >= lzd_min_free_bytes; } -static inline uint8_t LZd_get_prev_byte( const struct LZ_decoder * const decoder ) +static inline uint8_t LZd_get_prev_byte( const struct LZ_decoder * const d ) { - const int i = - ( ( decoder->cb.put > 0 ) ? decoder->cb.put : decoder->cb.buffer_size ) - 1; - return decoder->cb.buffer[i]; + const int i = ( ( d->cb.put > 0 ) ? d->cb.put : d->cb.buffer_size ) - 1; + return d->cb.buffer[i]; } -static inline uint8_t LZd_get_byte( const struct LZ_decoder * const decoder, +static inline uint8_t LZd_get_byte( const struct LZ_decoder * const d, const int distance ) { - int i = decoder->cb.put - distance - 1; - if( i < 0 ) i += decoder->cb.buffer_size; - return decoder->cb.buffer[i]; + int i = d->cb.put - distance - 1; + if( i < 0 ) i += d->cb.buffer_size; + return d->cb.buffer[i]; } -static inline void LZd_put_byte( struct LZ_decoder * const decoder, - const uint8_t b ) +static inline void LZd_put_byte( struct LZ_decoder * const d, const uint8_t b ) { - CRC32_update_byte( &decoder->crc, b ); - decoder->cb.buffer[decoder->cb.put] = b; - if( ++decoder->cb.put >= decoder->cb.buffer_size ) - { decoder->partial_data_pos += decoder->cb.put; decoder->cb.put = 0; } + CRC32_update_byte( &d->crc, b ); + d->cb.buffer[d->cb.put] = b; + if( ++d->cb.put >= d->cb.buffer_size ) + { d->partial_data_pos += d->cb.put; d->cb.put = 0; } } -static inline void LZd_copy_block( struct LZ_decoder * const decoder, +static inline void LZd_copy_block( struct LZ_decoder * const d, const int distance, int len ) { - int i = decoder->cb.put - distance - 1; - if( i < 0 ) i += decoder->cb.buffer_size; - if( len < decoder->cb.buffer_size - max( decoder->cb.put, i ) && - len <= abs( decoder->cb.put - i ) ) /* no wrap, no overlap */ + int i = d->cb.put - distance - 1; + if( i < 0 ) i += d->cb.buffer_size; + if( len < d->cb.buffer_size - max( d->cb.put, i ) && + len <= abs( d->cb.put - i ) ) /* no wrap, no overlap */ { - CRC32_update_buf( &decoder->crc, decoder->cb.buffer + i, len ); - memcpy( decoder->cb.buffer + decoder->cb.put, decoder->cb.buffer + i, len ); - decoder->cb.put += len; + CRC32_update_buf( &d->crc, d->cb.buffer + i, len ); + memcpy( d->cb.buffer + d->cb.put, d->cb.buffer + i, len ); + d->cb.put += len; } else for( ; len > 0; --len ) { - LZd_put_byte( decoder, decoder->cb.buffer[i] ); - if( ++i >= decoder->cb.buffer_size ) i = 0; + LZd_put_byte( d, d->cb.buffer[i] ); + if( ++i >= d->cb.buffer_size ) i = 0; } } -static inline bool LZd_init( struct LZ_decoder * const decoder, - const File_header header, - struct Range_decoder * const rde ) +static inline bool LZd_init( struct LZ_decoder * const d, + struct Range_decoder * const rde, + const int dict_size ) { - decoder->dictionary_size = Fh_get_dictionary_size( header ); - if( !Cb_init( &decoder->cb, max( 65536, decoder->dictionary_size ) + lzd_min_free_bytes ) ) + if( !Cb_init( &d->cb, max( 65536, dict_size ) + lzd_min_free_bytes ) ) return false; - decoder->partial_data_pos = 0; - decoder->crc = 0xFFFFFFFFU; - decoder->member_finished = false; - decoder->verify_trailer_pending = false; - decoder->rep0 = 0; - decoder->rep1 = 0; - decoder->rep2 = 0; - decoder->rep3 = 0; - decoder->state = 0; - - Bm_array_init( decoder->bm_literal[0], (1 << literal_context_bits) * 0x300 ); - Bm_array_init( decoder->bm_match[0], states * pos_states ); - Bm_array_init( decoder->bm_rep, states ); - Bm_array_init( decoder->bm_rep0, states ); - Bm_array_init( decoder->bm_rep1, states ); - Bm_array_init( decoder->bm_rep2, states ); - Bm_array_init( decoder->bm_len[0], states * pos_states ); - Bm_array_init( decoder->bm_dis_slot[0], len_states * (1 << dis_slot_bits) ); - Bm_array_init( decoder->bm_dis, modeled_distances - end_dis_model ); - Bm_array_init( decoder->bm_align, dis_align_size ); - - decoder->rdec = rde; - Lm_init( &decoder->match_len_model ); - Lm_init( &decoder->rep_len_model ); - decoder->cb.buffer[decoder->cb.buffer_size-1] = 0; /* prev_byte of first_byte */ + d->partial_data_pos = 0; + d->rdec = rde; + d->dictionary_size = dict_size; + d->crc = 0xFFFFFFFFU; + d->member_finished = false; + d->verify_trailer_pending = false; + d->rep0 = 0; + d->rep1 = 0; + d->rep2 = 0; + d->rep3 = 0; + d->state = 0; + + Bm_array_init( d->bm_literal[0], (1 << literal_context_bits) * 0x300 ); + Bm_array_init( d->bm_match[0], states * pos_states ); + Bm_array_init( d->bm_rep, states ); + Bm_array_init( d->bm_rep0, states ); + Bm_array_init( d->bm_rep1, states ); + Bm_array_init( d->bm_rep2, states ); + Bm_array_init( d->bm_len[0], states * pos_states ); + Bm_array_init( d->bm_dis_slot[0], len_states * (1 << dis_slot_bits) ); + Bm_array_init( d->bm_dis, modeled_distances - end_dis_model ); + Bm_array_init( d->bm_align, dis_align_size ); + + Lm_init( &d->match_len_model ); + Lm_init( &d->rep_len_model ); + d->cb.buffer[d->cb.buffer_size-1] = 0; /* prev_byte of first_byte */ return true; } -static inline void LZd_free( struct LZ_decoder * const decoder ) - { Cb_free( &decoder->cb ); } +static inline void LZd_free( struct LZ_decoder * const d ) + { Cb_free( &d->cb ); } -static inline bool LZd_member_finished( const struct LZ_decoder * const decoder ) - { return ( decoder->member_finished && !Cb_used_bytes( &decoder->cb ) ); } +static inline bool LZd_member_finished( const struct LZ_decoder * const d ) + { return ( d->member_finished && !Cb_used_bytes( &d->cb ) ); } -static inline unsigned LZd_crc( const struct LZ_decoder * const decoder ) - { return decoder->crc ^ 0xFFFFFFFFU; } +static inline unsigned LZd_crc( const struct LZ_decoder * const d ) + { return d->crc ^ 0xFFFFFFFFU; } static inline unsigned long long -LZd_data_position( const struct LZ_decoder * const decoder ) - { return decoder->partial_data_pos + decoder->cb.put; } +LZd_data_position( const struct LZ_decoder * const d ) + { return d->partial_data_pos + d->cb.put; } |