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-rw-r--r--decoder.c133
1 files changed, 67 insertions, 66 deletions
diff --git a/decoder.c b/decoder.c
index d659853..3dc62cc 100644
--- a/decoder.c
+++ b/decoder.c
@@ -1,5 +1,5 @@
/* Lzlib - Compression library for the lzip format
- Copyright (C) 2009-2018 Antonio Diaz Diaz.
+ Copyright (C) 2009-2019 Antonio Diaz Diaz.
This library is free software. Redistribution and use in source and
binary forms, with or without modification, are permitted provided
@@ -19,16 +19,16 @@
static int LZd_try_verify_trailer( struct LZ_decoder * const d )
{
- File_trailer trailer;
- if( Rd_available_bytes( d->rdec ) < Ft_size && !d->rdec->at_stream_end )
+ Lzip_trailer trailer;
+ if( Rd_available_bytes( d->rdec ) < Lt_size && !d->rdec->at_stream_end )
return 0;
d->verify_trailer_pending = false;
d->member_finished = true;
- if( Rd_read_data( d->rdec, trailer, Ft_size ) == Ft_size &&
- Ft_get_data_crc( trailer ) == LZd_crc( d ) &&
- Ft_get_data_size( trailer ) == LZd_data_position( d ) &&
- Ft_get_member_size( trailer ) == d->rdec->member_position ) return 0;
+ if( Rd_read_data( d->rdec, trailer, Lt_size ) == Lt_size &&
+ Lt_get_data_crc( trailer ) == LZd_crc( d ) &&
+ Lt_get_data_size( trailer ) == LZd_data_position( d ) &&
+ Lt_get_member_size( trailer ) == d->rdec->member_position ) return 0;
return 3;
}
@@ -49,15 +49,18 @@ static int LZd_decode_member( struct LZ_decoder * const d )
while( !Rd_finished( rdec ) )
{
+ int len;
const int pos_state = LZd_data_position( d ) & pos_state_mask;
/* const unsigned mpos = d->rdec->member_position;
if( mpos - old_mpos > rd_min_available_bytes ) return 5;
old_mpos = mpos; */
- if( !Rd_enough_available_bytes( rdec ) ) /* check unexpected eof */
- { if( !rdec->at_stream_end ) return 0; else break; }
+ if( !Rd_enough_available_bytes( rdec ) ) /* check unexpected EOF */
+ { if( !rdec->at_stream_end ) return 0;
+ if( Cb_empty( &rdec->cb ) ) break; } /* decode until EOF */
if( !LZd_enough_free_bytes( d ) ) return 0;
- if( Rd_decode_bit( rdec, &d->bm_match[*state][pos_state] ) == 0 ) /* 1st bit */
+ if( Rd_decode_bit( rdec, &d->bm_match[*state][pos_state] ) == 0 ) /* 1st bit */
{
+ /* literal byte */
Bit_model * const bm = d->bm_literal[get_lit_state(LZd_peek_prev( d ))];
if( St_is_char( *state ) )
{
@@ -69,79 +72,77 @@ static int LZd_decode_member( struct LZ_decoder * const d )
*state -= ( *state < 10 ) ? 3 : 6;
LZd_put_byte( d, Rd_decode_matched( rdec, bm, LZd_peek( d, d->rep0 ) ) );
}
+ continue;
}
- else /* match or repeated match */
+ /* match or repeated match */
+ if( Rd_decode_bit( rdec, &d->bm_rep[*state] ) != 0 ) /* 2nd bit */
{
- int len;
- if( Rd_decode_bit( rdec, &d->bm_rep[*state] ) != 0 ) /* 2nd bit */
+ if( Rd_decode_bit( rdec, &d->bm_rep0[*state] ) == 0 ) /* 3rd bit */
{
- if( Rd_decode_bit( rdec, &d->bm_rep0[*state] ) == 0 ) /* 3rd bit */
- {
- if( Rd_decode_bit( rdec, &d->bm_len[*state][pos_state] ) == 0 ) /* 4th bit */
- { *state = St_set_short_rep( *state );
- LZd_put_byte( d, LZd_peek( d, d->rep0 ) ); continue; }
- }
+ if( Rd_decode_bit( rdec, &d->bm_len[*state][pos_state] ) == 0 ) /* 4th bit */
+ { *state = St_set_short_rep( *state );
+ LZd_put_byte( d, LZd_peek( d, d->rep0 ) ); continue; }
+ }
+ else
+ {
+ unsigned distance;
+ if( Rd_decode_bit( rdec, &d->bm_rep1[*state] ) == 0 ) /* 4th bit */
+ distance = d->rep1;
else
{
- unsigned distance;
- if( Rd_decode_bit( rdec, &d->bm_rep1[*state] ) == 0 ) /* 4th bit */
- distance = d->rep1;
+ if( Rd_decode_bit( rdec, &d->bm_rep2[*state] ) == 0 ) /* 5th bit */
+ distance = d->rep2;
else
- {
- if( Rd_decode_bit( rdec, &d->bm_rep2[*state] ) == 0 ) /* 5th bit */
- distance = d->rep2;
- else
- { distance = d->rep3; d->rep3 = d->rep2; }
- d->rep2 = d->rep1;
- }
- d->rep1 = d->rep0;
- d->rep0 = distance;
+ { distance = d->rep3; d->rep3 = d->rep2; }
+ d->rep2 = d->rep1;
}
- *state = St_set_rep( *state );
- len = min_match_len + Rd_decode_len( rdec, &d->rep_len_model, pos_state );
+ d->rep1 = d->rep0;
+ d->rep0 = distance;
}
- else /* match */
+ *state = St_set_rep( *state );
+ len = min_match_len + Rd_decode_len( rdec, &d->rep_len_model, pos_state );
+ }
+ else /* match */
+ {
+ unsigned distance;
+ len = min_match_len + Rd_decode_len( rdec, &d->match_len_model, pos_state );
+ distance = Rd_decode_tree6( rdec, d->bm_dis_slot[get_len_state(len)] );
+ if( distance >= start_dis_model )
{
- unsigned distance;
- len = min_match_len + Rd_decode_len( rdec, &d->match_len_model, pos_state );
- distance = Rd_decode_tree6( rdec, d->bm_dis_slot[get_len_state(len)] );
- if( distance >= start_dis_model )
+ const unsigned dis_slot = distance;
+ const int direct_bits = ( dis_slot >> 1 ) - 1;
+ distance = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
+ if( dis_slot < end_dis_model )
+ distance += Rd_decode_tree_reversed( rdec,
+ d->bm_dis + ( distance - dis_slot ), direct_bits );
+ else
{
- const unsigned dis_slot = distance;
- const int direct_bits = ( dis_slot >> 1 ) - 1;
- distance = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
- if( dis_slot < end_dis_model )
- distance += Rd_decode_tree_reversed( rdec,
- d->bm_dis + ( distance - dis_slot ), direct_bits );
- else
+ distance +=
+ Rd_decode( rdec, direct_bits - dis_align_bits ) << dis_align_bits;
+ distance += Rd_decode_tree_reversed4( rdec, d->bm_align );
+ if( distance == 0xFFFFFFFFU ) /* marker found */
{
- distance +=
- Rd_decode( rdec, direct_bits - dis_align_bits ) << dis_align_bits;
- distance += Rd_decode_tree_reversed4( rdec, d->bm_align );
- if( distance == 0xFFFFFFFFU ) /* marker found */
+ Rd_normalize( rdec );
+ if( len == min_match_len ) /* End Of Stream marker */
+ {
+ d->verify_trailer_pending = true;
+ return LZd_try_verify_trailer( d );
+ }
+ if( len == min_match_len + 1 ) /* Sync Flush marker */
{
- Rd_normalize( rdec );
- if( len == min_match_len ) /* End Of Stream marker */
- {
- d->verify_trailer_pending = true;
- return LZd_try_verify_trailer( d );
- }
- if( len == min_match_len + 1 ) /* Sync Flush marker */
- {
- if( Rd_try_reload( rdec, true ) ) { /*old_mpos += 5;*/ continue; }
- else { if( !rdec->at_stream_end ) return 0; else break; }
- }
- return 4;
+ if( Rd_try_reload( rdec, true ) ) { /*old_mpos += 5;*/ continue; }
+ else { if( !rdec->at_stream_end ) return 0; else break; }
}
+ return 4;
}
}
- d->rep3 = d->rep2; d->rep2 = d->rep1; d->rep1 = d->rep0; d->rep0 = distance;
- *state = St_set_match( *state );
- if( d->rep0 >= d->dictionary_size ||
- ( d->rep0 >= d->cb.put && !d->pos_wrapped ) ) return 1;
}
- LZd_copy_block( d, d->rep0, len );
+ d->rep3 = d->rep2; d->rep2 = d->rep1; d->rep1 = d->rep0; d->rep0 = distance;
+ *state = St_set_match( *state );
+ if( d->rep0 >= d->dictionary_size ||
+ ( d->rep0 >= d->cb.put && !d->pos_wrapped ) ) return 1;
}
+ LZd_copy_block( d, d->rep0, len );
}
return 2;
}