1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/* Lzip - Data compressor based on the LZMA algorithm
Copyright (C) 2008, 2009, 2010, 2011 Antonio Diaz Diaz.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
class Fmatchfinder
{
enum { // bytes to keep in buffer before dictionary
before_size = max_match_len + 1,
// bytes to keep in buffer after pos
after_size = max_match_len,
num_prev_positions = 1 << 16 };
long long partial_data_pos;
uint8_t * buffer; // input buffer
int32_t * const prev_positions; // last seen position of key
int32_t * prev_pos_chain;
int dictionary_size_; // bytes to keep in buffer before pos
int buffer_size;
int pos; // current pos in buffer
int cyclic_pos; // current pos in dictionary
int key4; // key made from latest 4 bytes
int stream_pos; // first byte not yet read from file
int pos_limit; // when reached, a new block must be read
const int match_len_limit_;
const int infd; // input file descriptor
bool at_stream_end; // stream_pos shows real end of file
bool read_block();
public:
Fmatchfinder( const int ifd );
~Fmatchfinder()
{ delete[] prev_pos_chain; delete[] prev_positions; std::free( buffer ); }
uint8_t operator[]( const int i ) const throw() { return buffer[pos+i]; }
int available_bytes() const throw() { return stream_pos - pos; }
long long data_position() const throw() { return partial_data_pos + pos; }
int dictionary_size() const throw() { return dictionary_size_; }
bool finished() const throw() { return at_stream_end && pos >= stream_pos; }
int match_len_limit() const throw() { return match_len_limit_; }
const uint8_t * ptr_to_current_pos() const throw() { return buffer + pos; }
int true_match_len( const int index, const int distance, int len_limit ) const throw()
{
if( index + len_limit > available_bytes() )
len_limit = available_bytes() - index;
const uint8_t * const data = buffer + pos + index - distance;
int i = 0;
while( i < len_limit && data[i] == data[i+distance] ) ++i;
return i;
}
void reset();
void move_pos();
int longest_match_len( int * const distance ) throw();
void longest_match_len() throw();
};
class FLZ_encoder
{
enum { max_marker_size = 16,
num_rep_distances = 4 }; // must be 4
uint32_t crc_;
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];
Fmatchfinder & fmatchfinder;
Range_encoder range_encoder;
Len_encoder len_encoder;
Len_encoder rep_match_len_encoder;
Literal_encoder literal_encoder;
const int num_dis_slots;
int match_distance;
uint32_t crc() const throw() { return crc_ ^ 0xFFFFFFFFU; }
// move-to-front dis in/into reps
void mtf_reps( const int dis, int reps[num_rep_distances] ) throw()
{
if( dis >= num_rep_distances )
{
for( int i = num_rep_distances - 1; i > 0; --i ) reps[i] = reps[i-1];
reps[0] = dis - num_rep_distances;
}
else if( dis > 0 )
{
const int distance = reps[dis];
for( int i = dis; i > 0; --i ) reps[i] = reps[i-1];
reps[0] = distance;
}
}
void encode_pair( const uint32_t dis, const int len, const int pos_state ) throw()
{
len_encoder.encode( range_encoder, len, pos_state );
const int dis_slot = dis_slots[dis];
range_encoder.encode_tree( bm_dis_slot[get_dis_state(len)], dis_slot, dis_slot_bits );
if( dis_slot >= start_dis_model )
{
const int direct_bits = ( dis_slot >> 1 ) - 1;
const uint32_t base = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
const uint32_t direct_dis = dis - base;
if( dis_slot < end_dis_model )
range_encoder.encode_tree_reversed( bm_dis + base - dis_slot,
direct_dis, direct_bits );
else
{
range_encoder.encode( direct_dis >> dis_align_bits, direct_bits - dis_align_bits );
range_encoder.encode_tree_reversed( bm_align, direct_dis, dis_align_bits );
}
}
}
int read_match_distances() throw()
{
int len = fmatchfinder.longest_match_len( &match_distance );
if( len == fmatchfinder.match_len_limit() )
len += fmatchfinder.true_match_len( len, match_distance + 1, max_match_len - len );
return len;
}
void move_pos( int n, bool skip = false )
{
while( --n >= 0 )
{
if( skip ) skip = false;
else fmatchfinder.longest_match_len();
fmatchfinder.move_pos();
}
}
int sequence_optimizer( const int reps[num_rep_distances],
int * const disp, const State & state );
void full_flush( const State & state );
public:
FLZ_encoder( Fmatchfinder & mf, const File_header & header, const int outfd );
bool encode_member( const long long member_size );
long long member_position() const throw()
{ return range_encoder.member_position(); }
};
|
