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-rw-r--r--decoder.h146
1 files changed, 72 insertions, 74 deletions
diff --git a/decoder.h b/decoder.h
index c4135ff..5caa5c3 100644
--- a/decoder.h
+++ b/decoder.h
@@ -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; }