fenix
/
lzip
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases 1 Wiki Activity

Upload files to "/"

This commit is contained in:
fenix 2024-05-23 18:55:57 +02:00
parent 50e17e74d2
commit 12cac2c676
5 changed files with 1844 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

338
COPYING Normal file
View File

@ -0,0 +1,338 @@
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
Preamble
The licenses for most software are designed to take away your
freedom to share and change it. By contrast, the GNU General Public
License is intended to guarantee your freedom to share and change free
software--to make sure the software is free for all its users. This
General Public License applies to most of the Free Software
Foundation's software and to any other program whose authors commit to
using it. (Some other Free Software Foundation software is covered by
the GNU Lesser General Public License instead.) You can apply it to
your programs, too.
When we speak of free software, we are referring to freedom, not
price. Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
this service if you wish), that you receive source code or can get it
if you want it, that you can change the software or use pieces of it
in new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid
anyone to deny you these rights or to ask you to surrender the rights.
These restrictions translate to certain responsibilities for you if you
distribute copies of the software, or if you modify it.
For example, if you distribute copies of such a program, whether
gratis or for a fee, you must give the recipients all the rights that
you have. You must make sure that they, too, receive or can get the
source code. And you must show them these terms so they know their
rights.
We protect your rights with two steps: (1) copyright the software, and
(2) offer you this license which gives you legal permission to copy,
distribute and/or modify the software.
Also, for each author's protection and ours, we want to make certain
that everyone understands that there is no warranty for this free
software. If the software is modified by someone else and passed on, we
want its recipients to know that what they have is not the original, so
that any problems introduced by others will not reflect on the original
authors' reputations.
Finally, any free program is threatened constantly by software
patents. We wish to avoid the danger that redistributors of a free
program will individually obtain patent licenses, in effect making the
program proprietary. To prevent this, we have made it clear that any
patent must be licensed for everyone's free use or not licensed at all.
The precise terms and conditions for copying, distribution and
modification follow.
GNU GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies to any program or other work which contains
a notice placed by the copyright holder saying it may be distributed
under the terms of this General Public License. The "Program", below,
refers to any such program or work, and a "work based on the Program"
means either the Program or any derivative work under copyright law:
that is to say, a work containing the Program or a portion of it,
either verbatim or with modifications and/or translated into another
language. (Hereinafter, translation is included without limitation in
the term "modification".) Each licensee is addressed as "you".
Activities other than copying, distribution and modification are not
covered by this License; they are outside its scope. The act of
running the Program is not restricted, and the output from the Program
is covered only if its contents constitute a work based on the
Program (independent of having been made by running the Program).
Whether that is true depends on what the Program does.
1. You may copy and distribute verbatim copies of the Program's
source code as you receive it, in any medium, provided that you
conspicuously and appropriately publish on each copy an appropriate
copyright notice and disclaimer of warranty; keep intact all the
notices that refer to this License and to the absence of any warranty;
and give any other recipients of the Program a copy of this License
along with the Program.
You may charge a fee for the physical act of transferring a copy, and
you may at your option offer warranty protection in exchange for a fee.
2. You may modify your copy or copies of the Program or any portion
of it, thus forming a work based on the Program, and copy and
distribute such modifications or work under the terms of Section 1
above, provided that you also meet all of these conditions:
a) You must cause the modified files to carry prominent notices
stating that you changed the files and the date of any change.
b) You must cause any work that you distribute or publish, that in
whole or in part contains or is derived from the Program or any
part thereof, to be licensed as a whole at no charge to all third
parties under the terms of this License.
c) If the modified program normally reads commands interactively
when run, you must cause it, when started running for such
interactive use in the most ordinary way, to print or display an
announcement including an appropriate copyright notice and a
notice that there is no warranty (or else, saying that you provide
a warranty) and that users may redistribute the program under
these conditions, and telling the user how to view a copy of this
License. (Exception: if the Program itself is interactive but
does not normally print such an announcement, your work based on
the Program is not required to print an announcement.)
These requirements apply to the modified work as a whole. If
identifiable sections of that work are not derived from the Program,
and can be reasonably considered independent and separate works in
themselves, then this License, and its terms, do not apply to those
sections when you distribute them as separate works. But when you
distribute the same sections as part of a whole which is a work based
on the Program, the distribution of the whole must be on the terms of
this License, whose permissions for other licensees extend to the
entire whole, and thus to each and every part regardless of who wrote it.
Thus, it is not the intent of this section to claim rights or contest
your rights to work written entirely by you; rather, the intent is to
exercise the right to control the distribution of derivative or
collective works based on the Program.
In addition, mere aggregation of another work not based on the Program
with the Program (or with a work based on the Program) on a volume of
a storage or distribution medium does not bring the other work under
the scope of this License.
3. You may copy and distribute the Program (or a work based on it,
under Section 2) in object code or executable form under the terms of
Sections 1 and 2 above provided that you also do one of the following:
a) Accompany it with the complete corresponding machine-readable
source code, which must be distributed under the terms of Sections
1 and 2 above on a medium customarily used for software interchange; or,
b) Accompany it with a written offer, valid for at least three
years, to give any third party, for a charge no more than your
cost of physically performing source distribution, a complete
machine-readable copy of the corresponding source code, to be
distributed under the terms of Sections 1 and 2 above on a medium
customarily used for software interchange; or,
c) Accompany it with the information you received as to the offer
to distribute corresponding source code. (This alternative is
allowed only for noncommercial distribution and only if you
received the program in object code or executable form with such
an offer, in accord with Subsection b above.)
The source code for a work means the preferred form of the work for
making modifications to it. For an executable work, complete source
code means all the source code for all modules it contains, plus any
associated interface definition files, plus the scripts used to
control compilation and installation of the executable. However, as a
special exception, the source code distributed need not include
anything that is normally distributed (in either source or binary
form) with the major components (compiler, kernel, and so on) of the
operating system on which the executable runs, unless that component
itself accompanies the executable.
If distribution of executable or object code is made by offering
access to copy from a designated place, then offering equivalent
access to copy the source code from the same place counts as
distribution of the source code, even though third parties are not
compelled to copy the source along with the object code.
4. You may not copy, modify, sublicense, or distribute the Program
except as expressly provided under this License. Any attempt
otherwise to copy, modify, sublicense or distribute the Program is
void, and will automatically terminate your rights under this License.
However, parties who have received copies, or rights, from you under
this License will not have their licenses terminated so long as such
parties remain in full compliance.
5. You are not required to accept this License, since you have not
signed it. However, nothing else grants you permission to modify or
distribute the Program or its derivative works. These actions are
prohibited by law if you do not accept this License. Therefore, by
modifying or distributing the Program (or any work based on the
Program), you indicate your acceptance of this License to do so, and
all its terms and conditions for copying, distributing or modifying
the Program or works based on it.
6. Each time you redistribute the Program (or any work based on the
Program), the recipient automatically receives a license from the
original licensor to copy, distribute or modify the Program subject to
these terms and conditions. You may not impose any further
restrictions on the recipients' exercise of the rights granted herein.
You are not responsible for enforcing compliance by third parties to
this License.
7. If, as a consequence of a court judgment or allegation of patent
infringement or for any other reason (not limited to patent issues),
conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License. If you cannot
distribute so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you
may not distribute the Program at all. For example, if a patent
license would not permit royalty-free redistribution of the Program by
all those who receive copies directly or indirectly through you, then
the only way you could satisfy both it and this License would be to
refrain entirely from distribution of the Program.
If any portion of this section is held invalid or unenforceable under
any particular circumstance, the balance of the section is intended to
apply and the section as a whole is intended to apply in other
circumstances.
It is not the purpose of this section to induce you to infringe any
patents or other property right claims or to contest validity of any
such claims; this section has the sole purpose of protecting the
integrity of the free software distribution system, which is
implemented by public license practices. Many people have made
generous contributions to the wide range of software distributed
through that system in reliance on consistent application of that
system; it is up to the author/donor to decide if he or she is willing
to distribute software through any other system and a licensee cannot
impose that choice.
This section is intended to make thoroughly clear what is believed to
be a consequence of the rest of this License.
8. If the distribution and/or use of the Program is restricted in
certain countries either by patents or by copyrighted interfaces, the
original copyright holder who places the Program under this License
may add an explicit geographical distribution limitation excluding
those countries, so that distribution is permitted only in or among
countries not thus excluded. In such case, this License incorporates
the limitation as if written in the body of this License.
9. The Free Software Foundation may publish revised and/or new versions
of the General Public License from time to time. Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.
Each version is given a distinguishing version number. If the Program
specifies a version number of this License which applies to it and "any
later version", you have the option of following the terms and conditions
either of that version or of any later version published by the Free
Software Foundation. If the Program does not specify a version number of
this License, you may choose any version ever published by the Free Software
Foundation.
10. If you wish to incorporate parts of the Program into other free
programs whose distribution conditions are different, write to the author
to ask for permission. For software which is copyrighted by the Free
Software Foundation, write to the Free Software Foundation; we sometimes
make exceptions for this. Our decision will be guided by the two goals
of preserving the free status of all derivatives of our free software and
of promoting the sharing and reuse of software generally.
NO WARRANTY
11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
REPAIR OR CORRECTION.
12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.
END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest
to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.
<one line to give the program's name and a brief idea of what it does.>
Copyright (C) <year> <name of author>
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 2 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/>.
Also add information on how to contact you by electronic and paper mail.
If the program is interactive, make it output a short notice like this
when it starts in an interactive mode:
Gnomovision version 69, Copyright (C) <year> <name of author>
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
This is free software, and you are welcome to redistribute it
under certain conditions; type `show c' for details.
The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License. Of course, the commands you use may
be called something other than `show w' and `show c'; they could even be
mouse-clicks or menu items--whatever suits your program.
You should also get your employer (if you work as a programmer) or your
school, if any, to sign a "copyright disclaimer" for the program, if
necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the program
`Gnomovision' (which makes passes at compilers) written by James Hacker.
<signature of Ty Coon>, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incorporating your program into
proprietary programs. If your program is a subroutine library, you may
consider it more useful to permit linking proprietary applications with the
library. If this is what you want to do, use the GNU Lesser General
Public License instead of this License.

276
decoder.cc Normal file
View File

@ -0,0 +1,276 @@
/* Lzip - LZMA lossless data compressor
Copyright (C) 2008-2024 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 2 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/>.
*/
#define _FILE_OFFSET_BITS 64
#include <algorithm>
#include <cerrno>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include <stdint.h>
#include <unistd.h>
#include "lzip.h"
#include "decoder.h"
/* Return the number of bytes really read.
If (value returned < size) and (errno == 0), means EOF was reached.
*/
int readblock( const int fd, uint8_t * const buf, const int size )
{
int sz = 0;
errno = 0;
while( sz < size )
{
const int n = read( fd, buf + sz, size - sz );
if( n > 0 ) sz += n;
else if( n == 0 ) break; // EOF
else if( errno != EINTR ) break;
errno = 0;
}
return sz;
}
/* Return the number of bytes really written.
If (value returned < size), it is always an error.
*/
int writeblock( const int fd, const uint8_t * const buf, const int size )
{
int sz = 0;
errno = 0;
while( sz < size )
{
const int n = write( fd, buf + sz, size - sz );
if( n > 0 ) sz += n;
else if( n < 0 && errno != EINTR ) break;
errno = 0;
}
return sz;
}
bool Range_decoder::read_block()
{
if( !at_stream_end )
{
stream_pos = readblock( infd, buffer, buffer_size );
if( stream_pos != buffer_size && errno ) throw Error( "Read error" );
at_stream_end = ( stream_pos < buffer_size );
partial_member_pos += pos;
pos = 0;
show_dprogress();
}
return pos < stream_pos;
}
void LZ_decoder::flush_data()
{
if( pos > stream_pos )
{
const int size = pos - stream_pos;
crc32.update_buf( crc_, buffer + stream_pos, size );
if( outfd >= 0 && writeblock( outfd, buffer + stream_pos, size ) != size )
throw Error( "Write error" );
if( pos >= dictionary_size )
{ partial_data_pos += pos; pos = 0; pos_wrapped = true; }
stream_pos = pos;
}
}
int LZ_decoder::check_trailer( const Pretty_print & pp,
const bool ignore_empty ) const
{
Lzip_trailer trailer;
int size = rdec.read_data( trailer.data, trailer.size );
bool error = false;
if( size < trailer.size )
{
error = true;
if( verbosity >= 0 )
{ pp();
std::fprintf( stderr, "Trailer truncated at trailer position %d;"
" some checks may fail.\n", size ); }
while( size < trailer.size ) trailer.data[size++] = 0;
}
const unsigned td_crc = trailer.data_crc();
if( td_crc != crc() )
{
error = true;
if( verbosity >= 0 )
{ pp();
std::fprintf( stderr, "CRC mismatch; stored %08X, computed %08X\n",
td_crc, crc() ); }
}
const unsigned long long data_size = data_position();
const unsigned long long td_size = trailer.data_size();
if( td_size != data_size )
{
error = true;
if( verbosity >= 0 )
{ pp();
std::fprintf( stderr, "Data size mismatch; stored %llu (0x%llX), computed %llu (0x%llX)\n",
td_size, td_size, data_size, data_size ); }
}
const unsigned long long member_size = rdec.member_position();
const unsigned long long tm_size = trailer.member_size();
if( tm_size != member_size )
{
error = true;
if( verbosity >= 0 )
{ pp();
std::fprintf( stderr, "Member size mismatch; stored %llu (0x%llX), computed %llu (0x%llX)\n",
tm_size, tm_size, member_size, member_size ); }
}
if( error ) return 3;
if( !ignore_empty && data_size == 0 ) return 5;
if( verbosity >= 2 )
{
if( verbosity >= 4 ) show_header( dictionary_size );
if( data_size == 0 || member_size == 0 )
std::fputs( "no data compressed. ", stderr );
else
std::fprintf( stderr, "%6.3f:1, %5.2f%% ratio, %5.2f%% saved. ",
(double)data_size / member_size,
( 100.0 * member_size ) / data_size,
100.0 - ( ( 100.0 * member_size ) / data_size ) );
if( verbosity >= 4 ) std::fprintf( stderr, "CRC %08X, ", td_crc );
if( verbosity >= 3 )
std::fprintf( stderr, "%9llu out, %8llu in. ", data_size, member_size );
}
return 0;
}
/* Return value: 0 = OK, 1 = decoder error, 2 = unexpected EOF,
3 = trailer error, 4 = unknown marker found,
5 = empty member found, 6 = marked member found. */
int LZ_decoder::decode_member( const Cl_options & cl_opts,
const Pretty_print & pp )
{
Bit_model bm_literal[1<<literal_context_bits][0x300];
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[len_states][1<<dis_slot_bits];
Bit_model bm_dis[modeled_distances-end_dis_model+1];
Bit_model bm_align[dis_align_size];
Len_model match_len_model;
Len_model rep_len_model;
unsigned rep0 = 0; // rep[0-3] latest four distances
unsigned rep1 = 0; // used for efficient coding of
unsigned rep2 = 0; // repeated distances
unsigned rep3 = 0;
State state;
if( !rdec.load( cl_opts.ignore_marking ) ) return 6;
while( !rdec.finished() )
{
const int pos_state = data_position() & pos_state_mask;
if( rdec.decode_bit( bm_match[state()][pos_state] ) == 0 ) // 1st bit
{
// literal byte
Bit_model * const bm = bm_literal[get_lit_state(peek_prev())];
if( state.is_char_set_char() )
put_byte( rdec.decode_tree8( bm ) );
else
put_byte( rdec.decode_matched( bm, peek( rep0 ) ) );
continue;
}
// match or repeated match
int len;
if( rdec.decode_bit( bm_rep[state()] ) != 0 ) // 2nd bit
{
if( rdec.decode_bit( bm_rep0[state()] ) == 0 ) // 3rd bit
{
if( rdec.decode_bit( bm_len[state()][pos_state] ) == 0 ) // 4th bit
{ state.set_short_rep(); put_byte( peek( rep0 ) ); continue; }
}
else
{
unsigned distance;
if( rdec.decode_bit( bm_rep1[state()] ) == 0 ) // 4th bit
distance = rep1;
else
{
if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit
distance = rep2;
else
{ distance = rep3; rep3 = rep2; }
rep2 = rep1;
}
rep1 = rep0;
rep0 = distance;
}
state.set_rep();
len = rdec.decode_len( rep_len_model, pos_state );
}
else // match
{
len = rdec.decode_len( match_len_model, pos_state );
unsigned distance = rdec.decode_tree6( 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 += rdec.decode_tree_reversed(
bm_dis + ( distance - dis_slot ), direct_bits );
else
{
distance +=
rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits;
distance += rdec.decode_tree_reversed4( bm_align );
if( distance == 0xFFFFFFFFU ) // marker found
{
rdec.normalize();
flush_data();
if( len == min_match_len ) // End Of Stream marker
return check_trailer( pp, cl_opts.ignore_empty );
if( len == min_match_len + 1 ) // Sync Flush marker
{ rdec.load(); continue; }
if( verbosity >= 0 )
{
pp();
std::fprintf( stderr, "Unsupported marker code '%d'\n", len );
}
return 4;
}
}
}
rep3 = rep2; rep2 = rep1; rep1 = rep0; rep0 = distance;
state.set_match();
if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) )
{ flush_data(); return 1; }
}
copy_block( rep0, len );
}
flush_data();
return 2;
}

346
decoder.h Normal file
View File

@ -0,0 +1,346 @@
/* Lzip - LZMA lossless data compressor
Copyright (C) 2008-2024 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 2 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 Range_decoder
{
enum { buffer_size = 16384 };
unsigned long long partial_member_pos;
uint8_t * const buffer; // input buffer
int pos; // current pos in buffer
int stream_pos; // when reached, a new block must be read
uint32_t code;
uint32_t range;
const int infd; // input file descriptor
bool at_stream_end;
bool read_block();
Range_decoder( const Range_decoder & ); // declared as private
void operator=( const Range_decoder & ); // declared as private
public:
explicit Range_decoder( const int ifd )
:
partial_member_pos( 0 ),
buffer( new uint8_t[buffer_size] ),
pos( 0 ),
stream_pos( 0 ),
code( 0 ),
range( 0xFFFFFFFFU ),
infd( ifd ),
at_stream_end( false )
{}
~Range_decoder() { delete[] buffer; }
bool finished() { return pos >= stream_pos && !read_block(); }
unsigned long long member_position() const
{ return partial_member_pos + pos; }
void reset_member_position()
{ partial_member_pos = 0; partial_member_pos -= pos; }
uint8_t get_byte()
{
// 0xFF avoids decoder error if member is truncated at EOS marker
if( finished() ) return 0xFF;
return buffer[pos++];
}
int read_data( uint8_t * const outbuf, const int size )
{
int sz = 0;
while( sz < size && !finished() )
{
const int rd = std::min( size - sz, stream_pos - pos );
std::memcpy( outbuf + sz, buffer + pos, rd );
pos += rd;
sz += rd;
}
return sz;
}
bool load( const bool ignore_marking = true )
{
code = 0;
range = 0xFFFFFFFFU;
// check and discard first byte of the LZMA stream
if( get_byte() != 0 && !ignore_marking ) return false;
for( int i = 0; i < 4; ++i ) code = ( code << 8 ) | get_byte();
return true;
}
void normalize()
{
if( range <= 0x00FFFFFFU )
{ range <<= 8; code = ( code << 8 ) | get_byte(); }
}
unsigned decode( const int num_bits )
{
unsigned symbol = 0;
for( int i = num_bits; i > 0; --i )
{
normalize();
range >>= 1;
// symbol <<= 1;
// if( code >= range ) { code -= range; symbol |= 1; }
const bool bit = ( code >= range );
symbol <<= 1; symbol += bit;
code -= range & ( 0U - bit );
}
return symbol;
}
bool decode_bit( Bit_model & bm )
{
normalize();
const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
if( code < bound )
{
range = bound;
bm.probability +=
( bit_model_total - bm.probability ) >> bit_model_move_bits;
return 0;
}
else
{
code -= bound;
range -= bound;
bm.probability -= bm.probability >> bit_model_move_bits;
return 1;
}
}
void decode_symbol_bit( Bit_model & bm, unsigned & symbol )
{
normalize();
symbol <<= 1;
const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
if( code < bound )
{
range = bound;
bm.probability +=
( bit_model_total - bm.probability ) >> bit_model_move_bits;
}
else
{
code -= bound;
range -= bound;
bm.probability -= bm.probability >> bit_model_move_bits;
symbol |= 1;
}
}
void decode_symbol_bit_reversed( Bit_model & bm, unsigned & model,
unsigned & symbol, const int i )
{
normalize();
model <<= 1;
const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
if( code < bound )
{
range = bound;
bm.probability +=
( bit_model_total - bm.probability ) >> bit_model_move_bits;
}
else
{
code -= bound;
range -= bound;
bm.probability -= bm.probability >> bit_model_move_bits;
model |= 1;
symbol |= 1 << i;
}
}
unsigned decode_tree6( Bit_model bm[] )
{
unsigned symbol = 1;
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
return symbol & 0x3F;
}
unsigned decode_tree8( Bit_model bm[] )
{
unsigned symbol = 1;
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
return symbol & 0xFF;
}
unsigned decode_tree_reversed( Bit_model bm[], const int num_bits )
{
unsigned model = 1;
unsigned symbol = 0;
for( int i = 0; i < num_bits; ++i )
decode_symbol_bit_reversed( bm[model], model, symbol, i );
return symbol;
}
unsigned decode_tree_reversed4( Bit_model bm[] )
{
unsigned model = 1;
unsigned symbol = 0;
decode_symbol_bit_reversed( bm[model], model, symbol, 0 );
decode_symbol_bit_reversed( bm[model], model, symbol, 1 );
decode_symbol_bit_reversed( bm[model], model, symbol, 2 );
decode_symbol_bit_reversed( bm[model], model, symbol, 3 );
return symbol;
}
unsigned decode_matched( Bit_model bm[], unsigned match_byte )
{
Bit_model * const bm1 = bm + 0x100;
unsigned symbol = 1;
while( symbol < 0x100 )
{
const unsigned match_bit = ( match_byte <<= 1 ) & 0x100;
const bool bit = decode_bit( bm1[symbol+match_bit] );
symbol <<= 1; symbol |= bit;
if( match_bit >> 8 != bit )
{
while( symbol < 0x100 ) decode_symbol_bit( bm[symbol], symbol );
break;
}
}
return symbol & 0xFF;
}
unsigned decode_len( Len_model & lm, const int pos_state )
{
Bit_model * bm;
unsigned mask, offset, symbol = 1;
if( decode_bit( lm.choice1 ) == 0 )
{ bm = lm.bm_low[pos_state]; mask = 7; offset = 0; goto len3; }
if( decode_bit( lm.choice2 ) == 0 )
{ bm = lm.bm_mid[pos_state]; mask = 7; offset = len_low_symbols; goto len3; }
bm = lm.bm_high; mask = 0xFF; offset = len_low_symbols + len_mid_symbols;
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
len3:
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
decode_symbol_bit( bm[symbol], symbol );
return ( symbol & mask ) + min_match_len + offset;
}
};
class LZ_decoder
{
unsigned long long partial_data_pos;
Range_decoder & rdec;
const unsigned dictionary_size;
uint8_t * const buffer; // output buffer
unsigned pos; // current pos in buffer
unsigned stream_pos; // first byte not yet written to file
uint32_t crc_;
const int outfd; // output file descriptor
bool pos_wrapped;
void flush_data();
int check_trailer( const Pretty_print & pp, const bool ignore_empty ) const;
uint8_t peek_prev() const
{ return buffer[((pos > 0) ? pos : dictionary_size)-1]; }
uint8_t peek( const unsigned distance ) const
{
const unsigned i = ( ( pos > distance ) ? 0 : dictionary_size ) +
pos - distance - 1;
return buffer[i];
}
void put_byte( const uint8_t b )
{
buffer[pos] = b;
if( ++pos >= dictionary_size ) flush_data();
}
void copy_block( const unsigned distance, unsigned len )
{
unsigned lpos = pos, i = lpos - distance - 1;
bool fast, fast2;
if( lpos > distance )
{
fast = ( len < dictionary_size - lpos );
fast2 = ( fast && len <= lpos - i );
}
else
{
i += dictionary_size;
fast = ( len < dictionary_size - i ); // (i == pos) may happen
fast2 = ( fast && len <= i - lpos );
}
if( fast ) // no wrap
{
pos += len;
if( fast2 ) // no wrap, no overlap
std::memcpy( buffer + lpos, buffer + i, len );
else
for( ; len > 0; --len ) buffer[lpos++] = buffer[i++];
}
else for( ; len > 0; --len )
{
buffer[pos] = buffer[i];
if( ++pos >= dictionary_size ) flush_data();
if( ++i >= dictionary_size ) i = 0;
}
}
LZ_decoder( const LZ_decoder & ); // declared as private
void operator=( const LZ_decoder & ); // declared as private
public:
LZ_decoder( Range_decoder & rde, const unsigned dict_size, const int ofd )
:
partial_data_pos( 0 ),
rdec( rde ),
dictionary_size( dict_size ),
buffer( new uint8_t[dictionary_size] ),
pos( 0 ),
stream_pos( 0 ),
crc_( 0xFFFFFFFFU ),
outfd( ofd ),
pos_wrapped( false )
// prev_byte of first byte; also for peek( 0 ) on corrupt file
{ buffer[dictionary_size-1] = 0; }
~LZ_decoder() { delete[] buffer; }
unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; }
unsigned long long data_position() const { return partial_data_pos + pos; }
int decode_member( const Cl_options & cl_opts, const Pretty_print & pp );
};

594
encoder.cc Normal file
View File

@ -0,0 +1,594 @@
/* Lzip - LZMA lossless data compressor
Copyright (C) 2008-2024 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 2 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/>.
*/
#define _FILE_OFFSET_BITS 64
#include <algorithm>
#include <cerrno>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include <stdint.h>
#include "lzip.h"
#include "encoder_base.h"
#include "encoder.h"
const CRC32 crc32;
int LZ_encoder::get_match_pairs( Pair * pairs )
{
int len_limit = match_len_limit;
if( len_limit > available_bytes() )
{
len_limit = available_bytes();
if( len_limit < 4 ) return 0;
}
int maxlen = 3; // only used if pairs != 0
int num_pairs = 0;
const int min_pos = ( pos > dictionary_size ) ? pos - dictionary_size : 0;
const uint8_t * const data = ptr_to_current_pos();
unsigned tmp = crc32[data[0]] ^ data[1];
const int key2 = tmp & ( num_prev_positions2 - 1 );
tmp ^= (unsigned)data[2] << 8;
const int key3 = num_prev_positions2 + ( tmp & ( num_prev_positions3 - 1 ) );
const int key4 = num_prev_positions23 +
( ( tmp ^ ( crc32[data[3]] << 5 ) ) & key4_mask );
if( pairs )
{
const int np2 = prev_positions[key2];
const int np3 = prev_positions[key3];
if( np2 > min_pos && buffer[np2-1] == data[0] )
{
pairs[0].dis = pos - np2;
pairs[0].len = maxlen = 2 + ( np2 == np3 );
num_pairs = 1;
}
if( np2 != np3 && np3 > min_pos && buffer[np3-1] == data[0] )
{
maxlen = 3;
pairs[num_pairs++].dis = pos - np3;
}
if( num_pairs > 0 )
{
const int delta = pairs[num_pairs-1].dis + 1;
while( maxlen < len_limit && data[maxlen-delta] == data[maxlen] )
++maxlen;
pairs[num_pairs-1].len = maxlen;
if( maxlen < 3 ) maxlen = 3;
if( maxlen >= len_limit ) pairs = 0; // done. now just skip
}
}
const int pos1 = pos + 1;
prev_positions[key2] = pos1;
prev_positions[key3] = pos1;
int newpos1 = prev_positions[key4];
prev_positions[key4] = pos1;
int32_t * ptr0 = pos_array + ( cyclic_pos << 1 );
int32_t * ptr1 = ptr0 + 1;
int len = 0, len0 = 0, len1 = 0;
for( int count = cycles; ; )
{
if( newpos1 <= min_pos || --count < 0 ) { *ptr0 = *ptr1 = 0; break; }
const int delta = pos1 - newpos1;
int32_t * const newptr = pos_array +
( ( cyclic_pos - delta +
( ( cyclic_pos >= delta ) ? 0 : dictionary_size + 1 ) ) << 1 );
if( data[len-delta] == data[len] )
{
while( ++len < len_limit && data[len-delta] == data[len] ) {}
if( pairs && maxlen < len )
{
pairs[num_pairs].dis = delta - 1;
pairs[num_pairs].len = maxlen = len;
++num_pairs;
}
if( len >= len_limit )
{
*ptr0 = newptr[0];
*ptr1 = newptr[1];
break;
}
}
if( data[len-delta] < data[len] )
{
*ptr0 = newpos1;
ptr0 = newptr + 1;
newpos1 = *ptr0;
len0 = len; if( len1 < len ) len = len1;
}
else
{
*ptr1 = newpos1;
ptr1 = newptr;
newpos1 = *ptr1;
len1 = len; if( len0 < len ) len = len0;
}
}
return num_pairs;
}
void LZ_encoder::update_distance_prices()
{
for( int dis = start_dis_model; dis < modeled_distances; ++dis )
{
const int dis_slot = dis_slots[dis];
const int direct_bits = ( dis_slot >> 1 ) - 1;
const int base = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
const int price = price_symbol_reversed( bm_dis + ( base - dis_slot ),
dis - base, direct_bits );
for( int len_state = 0; len_state < len_states; ++len_state )
dis_prices[len_state][dis] = price;
}
for( int len_state = 0; len_state < len_states; ++len_state )
{
int * const dsp = dis_slot_prices[len_state];
const Bit_model * const bmds = bm_dis_slot[len_state];
int slot = 0;
for( ; slot < end_dis_model; ++slot )
dsp[slot] = price_symbol6( bmds, slot );
for( ; slot < num_dis_slots; ++slot )
dsp[slot] = price_symbol6( bmds, slot ) +
(((( slot >> 1 ) - 1 ) - dis_align_bits ) << price_shift_bits );
int * const dp = dis_prices[len_state];
int dis = 0;
for( ; dis < start_dis_model; ++dis )
dp[dis] = dsp[dis];
for( ; dis < modeled_distances; ++dis )
dp[dis] += dsp[dis_slots[dis]];
}
}
/* Return the number of bytes advanced (ahead).
trials[0]..trials[ahead-1] contain the steps to encode.
( trials[0].dis4 == -1 ) means literal.
A match/rep longer or equal than match_len_limit finishes the sequence.
*/
int LZ_encoder::sequence_optimizer( const int reps[num_rep_distances],
const State state )
{
int num_pairs, num_trials;
if( pending_num_pairs > 0 ) // from previous call
{
num_pairs = pending_num_pairs;
pending_num_pairs = 0;
}
else
num_pairs = read_match_distances();
const int main_len = ( num_pairs > 0 ) ? pairs[num_pairs-1].len : 0;
int replens[num_rep_distances];
int rep_index = 0;
for( int i = 0; i < num_rep_distances; ++i )
{
replens[i] = true_match_len( 0, reps[i] + 1 );
if( replens[i] > replens[rep_index] ) rep_index = i;
}
if( replens[rep_index] >= match_len_limit )
{
trials[0].price = replens[rep_index];
trials[0].dis4 = rep_index;
move_and_update( replens[rep_index] );
return replens[rep_index];
}
if( main_len >= match_len_limit )
{
trials[0].price = main_len;
trials[0].dis4 = pairs[num_pairs-1].dis + num_rep_distances;
move_and_update( main_len );
return main_len;
}
const int pos_state = data_position() & pos_state_mask;
const uint8_t prev_byte = peek( 1 );
const uint8_t cur_byte = peek( 0 );
const uint8_t match_byte = peek( reps[0] + 1 );
trials[1].price = price0( bm_match[state()][pos_state] );
if( state.is_char() )
trials[1].price += price_literal( prev_byte, cur_byte );
else
trials[1].price += price_matched( prev_byte, cur_byte, match_byte );
trials[1].dis4 = -1; // literal
const int match_price = price1( bm_match[state()][pos_state] );
const int rep_match_price = match_price + price1( bm_rep[state()] );
if( match_byte == cur_byte )
trials[1].update( rep_match_price + price_shortrep( state, pos_state ), 0, 0 );
num_trials = std::max( main_len, replens[rep_index] );
if( num_trials < min_match_len )
{
trials[0].price = 1;
trials[0].dis4 = trials[1].dis4;
move_pos();
return 1;
}
trials[0].state = state;
for( int i = 0; i < num_rep_distances; ++i )
trials[0].reps[i] = reps[i];
for( int len = min_match_len; len <= num_trials; ++len )
trials[len].price = infinite_price;
for( int rep = 0; rep < num_rep_distances; ++rep )
{
if( replens[rep] < min_match_len ) continue;
const int price = rep_match_price + price_rep( rep, state, pos_state );
for( int len = min_match_len; len <= replens[rep]; ++len )
trials[len].update( price + rep_len_prices.price( len, pos_state ),
rep, 0 );
}
if( main_len > replens[0] )
{
const int normal_match_price = match_price + price0( bm_rep[state()] );
int i = 0, len = std::max( replens[0] + 1, (int)min_match_len );
while( len > pairs[i].len ) ++i;
while( true )
{
const int dis = pairs[i].dis;
trials[len].update( normal_match_price + price_pair( dis, len, pos_state ),
dis + num_rep_distances, 0 );
if( ++len > pairs[i].len && ++i >= num_pairs ) break;
}
}
int cur = 0;
while( true ) // price optimization loop
{
move_pos();
if( ++cur >= num_trials ) // no more initialized trials
{
backward( cur );
return cur;
}
const int num_pairs = read_match_distances();
const int newlen = ( num_pairs > 0 ) ? pairs[num_pairs-1].len : 0;
if( newlen >= match_len_limit )
{
pending_num_pairs = num_pairs;
backward( cur );
return cur;
}
// give final values to current trial
Trial & cur_trial = trials[cur];
State cur_state;
{
const int dis4 = cur_trial.dis4;
int prev_index = cur_trial.prev_index;
const int prev_index2 = cur_trial.prev_index2;
if( prev_index2 == single_step_trial )
{
cur_state = trials[prev_index].state;
if( prev_index + 1 == cur ) // len == 1
{
if( dis4 == 0 ) cur_state.set_short_rep();
else cur_state.set_char(); // literal
}
else if( dis4 < num_rep_distances ) cur_state.set_rep();
else cur_state.set_match();
}
else
{
if( prev_index2 == dual_step_trial ) // dis4 == 0 (rep0)
--prev_index;
else // prev_index2 >= 0
prev_index = prev_index2;
cur_state.set_char_rep();
}
cur_trial.state = cur_state;
for( int i = 0; i < num_rep_distances; ++i )
cur_trial.reps[i] = trials[prev_index].reps[i];
mtf_reps( dis4, cur_trial.reps ); // literal is ignored
}
const int pos_state = data_position() & pos_state_mask;
const uint8_t prev_byte = peek( 1 );
const uint8_t cur_byte = peek( 0 );
const uint8_t match_byte = peek( cur_trial.reps[0] + 1 );
int next_price = cur_trial.price +
price0( bm_match[cur_state()][pos_state] );
if( cur_state.is_char() )
next_price += price_literal( prev_byte, cur_byte );
else
next_price += price_matched( prev_byte, cur_byte, match_byte );
// try last updates to next trial
Trial & next_trial = trials[cur+1];
next_trial.update( next_price, -1, cur ); // literal
const int match_price = cur_trial.price + price1( bm_match[cur_state()][pos_state] );
const int rep_match_price = match_price + price1( bm_rep[cur_state()] );
if( match_byte == cur_byte && next_trial.dis4 != 0 &&
next_trial.prev_index2 == single_step_trial )
{
const int price = rep_match_price + price_shortrep( cur_state, pos_state );
if( price <= next_trial.price )
{
next_trial.price = price;
next_trial.dis4 = 0; // rep0
next_trial.prev_index = cur;
}
}
const int triable_bytes =
std::min( available_bytes(), max_num_trials - 1 - cur );
if( triable_bytes < min_match_len ) continue;
const int len_limit = std::min( match_len_limit, triable_bytes );
// try literal + rep0
if( match_byte != cur_byte && next_trial.prev_index != cur )
{
const uint8_t * const data = ptr_to_current_pos();
const int dis = cur_trial.reps[0] + 1;
const int limit = std::min( match_len_limit + 1, triable_bytes );
int len = 1;
while( len < limit && data[len-dis] == data[len] ) ++len;
if( --len >= min_match_len )
{
const int pos_state2 = ( pos_state + 1 ) & pos_state_mask;
State state2 = cur_state; state2.set_char();
const int price = next_price +
price1( bm_match[state2()][pos_state2] ) +
price1( bm_rep[state2()] ) +
price_rep0_len( len, state2, pos_state2 );
while( num_trials < cur + 1 + len )
trials[++num_trials].price = infinite_price;
trials[cur+1+len].update2( price, cur + 1 );
}
}
int start_len = min_match_len;
// try rep distances
for( int rep = 0; rep < num_rep_distances; ++rep )
{
const uint8_t * const data = ptr_to_current_pos();
const int dis = cur_trial.reps[rep] + 1;
int len;
if( data[0-dis] != data[0] || data[1-dis] != data[1] ) continue;
for( len = min_match_len; len < len_limit; ++len )
if( data[len-dis] != data[len] ) break;
while( num_trials < cur + len )
trials[++num_trials].price = infinite_price;
int price = rep_match_price + price_rep( rep, cur_state, pos_state );
for( int i = min_match_len; i <= len; ++i )
trials[cur+i].update( price + rep_len_prices.price( i, pos_state ),
rep, cur );
if( rep == 0 ) start_len = len + 1; // discard shorter matches
// try rep + literal + rep0
int len2 = len + 1;
const int limit = std::min( match_len_limit + len2, triable_bytes );
while( len2 < limit && data[len2-dis] == data[len2] ) ++len2;
len2 -= len + 1;
if( len2 < min_match_len ) continue;
int pos_state2 = ( pos_state + len ) & pos_state_mask;
State state2 = cur_state; state2.set_rep();
price += rep_len_prices.price( len, pos_state ) +
price0( bm_match[state2()][pos_state2] ) +
price_matched( data[len-1], data[len], data[len-dis] );
pos_state2 = ( pos_state2 + 1 ) & pos_state_mask;
state2.set_char();
price += price1( bm_match[state2()][pos_state2] ) +
price1( bm_rep[state2()] ) +
price_rep0_len( len2, state2, pos_state2 );
while( num_trials < cur + len + 1 + len2 )
trials[++num_trials].price = infinite_price;
trials[cur+len+1+len2].update3( price, rep, cur + len + 1, cur );
}
// try matches
if( newlen >= start_len && newlen <= len_limit )
{
const int normal_match_price = match_price +
price0( bm_rep[cur_state()] );
while( num_trials < cur + newlen )
trials[++num_trials].price = infinite_price;
int i = 0;
while( pairs[i].len < start_len ) ++i;
int dis = pairs[i].dis;
for( int len = start_len; ; ++len )
{
int price = normal_match_price + price_pair( dis, len, pos_state );
trials[cur+len].update( price, dis + num_rep_distances, cur );
// try match + literal + rep0
if( len == pairs[i].len )
{
const uint8_t * const data = ptr_to_current_pos();
const int dis2 = dis + 1;
int len2 = len + 1;
const int limit = std::min( match_len_limit + len2, triable_bytes );
while( len2 < limit && data[len2-dis2] == data[len2] ) ++len2;
len2 -= len + 1;
if( len2 >= min_match_len )
{
int pos_state2 = ( pos_state + len ) & pos_state_mask;
State state2 = cur_state; state2.set_match();
price += price0( bm_match[state2()][pos_state2] ) +
price_matched( data[len-1], data[len], data[len-dis2] );
pos_state2 = ( pos_state2 + 1 ) & pos_state_mask;
state2.set_char();
price += price1( bm_match[state2()][pos_state2] ) +
price1( bm_rep[state2()] ) +
price_rep0_len( len2, state2, pos_state2 );
while( num_trials < cur + len + 1 + len2 )
trials[++num_trials].price = infinite_price;
trials[cur+len+1+len2].update3( price, dis + num_rep_distances,
cur + len + 1, cur );
}
if( ++i >= num_pairs ) break;
dis = pairs[i].dis;
}
}
}
}
}
bool LZ_encoder::encode_member( const unsigned long long member_size )
{
const unsigned long long member_size_limit =
member_size - Lzip_trailer::size - max_marker_size;
const bool best = ( match_len_limit > 12 );
const int dis_price_count = best ? 1 : 512;
const int align_price_count = best ? 1 : dis_align_size;
const int price_count = ( match_len_limit > 36 ) ? 1013 : 4093;
int price_counter = 0; // counters may decrement below 0
int dis_price_counter = 0;
int align_price_counter = 0;
int reps[num_rep_distances];
State state;
for( int i = 0; i < num_rep_distances; ++i ) reps[i] = 0;
if( data_position() != 0 || renc.member_position() != Lzip_header::size )
return false; // can be called only once
if( !data_finished() ) // encode first byte
{
const uint8_t prev_byte = 0;
const uint8_t cur_byte = peek( 0 );
renc.encode_bit( bm_match[state()][0], 0 );
encode_literal( prev_byte, cur_byte );
crc32.update_byte( crc_, cur_byte );
get_match_pairs();
move_pos();
}
while( !data_finished() )
{
if( price_counter <= 0 && pending_num_pairs == 0 )
{
price_counter = price_count; // recalculate prices every these bytes
if( dis_price_counter <= 0 )
{ dis_price_counter = dis_price_count; update_distance_prices(); }
if( align_price_counter <= 0 )
{
align_price_counter = align_price_count;
for( int i = 0; i < dis_align_size; ++i )
align_prices[i] = price_symbol_reversed( bm_align, i, dis_align_bits );
}
match_len_prices.update_prices();
rep_len_prices.update_prices();
}
int ahead = sequence_optimizer( reps, state );
price_counter -= ahead;
for( int i = 0; ahead > 0; )
{
const int pos_state = ( data_position() - ahead ) & pos_state_mask;
const int len = trials[i].price;
int dis = trials[i].dis4;
bool bit = ( dis < 0 );
renc.encode_bit( bm_match[state()][pos_state], !bit );
if( bit ) // literal byte
{
const uint8_t prev_byte = peek( ahead + 1 );
const uint8_t cur_byte = peek( ahead );
crc32.update_byte( crc_, cur_byte );
if( state.is_char_set_char() )
encode_literal( prev_byte, cur_byte );
else
{
const uint8_t match_byte = peek( ahead + reps[0] + 1 );
encode_matched( prev_byte, cur_byte, match_byte );
}
}
else // match or repeated match
{
crc32.update_buf( crc_, ptr_to_current_pos() - ahead, len );
mtf_reps( dis, reps );
bit = ( dis < num_rep_distances );
renc.encode_bit( bm_rep[state()], bit );
if( bit ) // repeated match
{
bit = ( dis == 0 );
renc.encode_bit( bm_rep0[state()], !bit );
if( bit )
renc.encode_bit( bm_len[state()][pos_state], len > 1 );
else
{
renc.encode_bit( bm_rep1[state()], dis > 1 );
if( dis > 1 )
renc.encode_bit( bm_rep2[state()], dis > 2 );
}
if( len == 1 ) state.set_short_rep();
else
{
renc.encode_len( rep_len_model, len, pos_state );
rep_len_prices.decrement_counter( pos_state );
state.set_rep();
}
}
else // match
{
dis -= num_rep_distances;
encode_pair( dis, len, pos_state );
if( dis >= modeled_distances ) --align_price_counter;
--dis_price_counter;
match_len_prices.decrement_counter( pos_state );
state.set_match();
}
}
ahead -= len; i += len;
if( renc.member_position() >= member_size_limit )
{
if( !dec_pos( ahead ) ) return false;
full_flush( state );
return true;
}
}
}
full_flush( state );
return true;
}

290
encoder.h Normal file
View File

@ -0,0 +1,290 @@
/* Lzip - LZMA lossless data compressor
Copyright (C) 2008-2024 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 2 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 Len_prices
{
const Len_model & lm;
const int len_symbols;
const int count;
int prices[pos_states][max_len_symbols];
int counters[pos_states]; // may decrement below 0
void update_low_mid_prices( const int pos_state )
{
int * const pps = prices[pos_state];
int tmp = price0( lm.choice1 );
int len = 0;
for( ; len < len_low_symbols && len < len_symbols; ++len )
pps[len] = tmp + price_symbol3( lm.bm_low[pos_state], len );
if( len >= len_symbols ) return;
tmp = price1( lm.choice1 ) + price0( lm.choice2 );
for( ; len < len_low_symbols + len_mid_symbols && len < len_symbols; ++len )
pps[len] = tmp +
price_symbol3( lm.bm_mid[pos_state], len - len_low_symbols );
}
void update_high_prices()
{
const int tmp = price1( lm.choice1 ) + price1( lm.choice2 );
for( int len = len_low_symbols + len_mid_symbols; len < len_symbols; ++len )
// using 4 slots per value makes "price" faster
prices[3][len] = prices[2][len] = prices[1][len] = prices[0][len] = tmp +
price_symbol8( lm.bm_high, len - len_low_symbols - len_mid_symbols );
}
public:
void reset() { for( int i = 0; i < pos_states; ++i ) counters[i] = 0; }
Len_prices( const Len_model & m, const int match_len_limit )
:
lm( m ),
len_symbols( match_len_limit + 1 - min_match_len ),
count( ( match_len_limit > 12 ) ? 1 : len_symbols )
{ reset(); }
void decrement_counter( const int pos_state ) { --counters[pos_state]; }
void update_prices()
{
bool high_pending = false;
for( int pos_state = 0; pos_state < pos_states; ++pos_state )
if( counters[pos_state] <= 0 )
{ counters[pos_state] = count;
update_low_mid_prices( pos_state ); high_pending = true; }
if( high_pending && len_symbols > len_low_symbols + len_mid_symbols )
update_high_prices();
}
int price( const int len, const int pos_state ) const
{ return prices[pos_state][len - min_match_len]; }
};
class LZ_encoder : public LZ_encoder_base
{
struct Pair // distance-length pair
{
int dis;
int len;
};
enum { infinite_price = 0x0FFFFFFF,
max_num_trials = 1 << 13,
single_step_trial = -2,
dual_step_trial = -1 };
struct Trial
{
State state;
int price; // dual use var; cumulative price, match length
int dis4; // -1 for literal, or rep, or match distance + 4
int prev_index; // index of prev trial in trials[]
int prev_index2; // -2 trial is single step
// -1 literal + rep0
// >= 0 ( rep or match ) + literal + rep0
int reps[num_rep_distances];
void update( const int pr, const int distance4, const int p_i )
{
if( pr < price )
{ price = pr; dis4 = distance4; prev_index = p_i;
prev_index2 = single_step_trial; }
}
void update2( const int pr, const int p_i )
{
if( pr < price )
{ price = pr; dis4 = 0; prev_index = p_i;
prev_index2 = dual_step_trial; }
}
void update3( const int pr, const int distance4, const int p_i,
const int p_i2 )
{
if( pr < price )
{ price = pr; dis4 = distance4; prev_index = p_i;
prev_index2 = p_i2; }
}
};
const int cycles;
const int match_len_limit;
Len_prices match_len_prices;
Len_prices rep_len_prices;
int pending_num_pairs;
Pair pairs[max_match_len+1];
Trial trials[max_num_trials];
int dis_slot_prices[len_states][2*max_dictionary_bits];
int dis_prices[len_states][modeled_distances];
int align_prices[dis_align_size];
const int num_dis_slots;
bool dec_pos( const int ahead )
{
if( ahead < 0 || pos < ahead ) return false;
pos -= ahead;
if( cyclic_pos < ahead ) cyclic_pos += dictionary_size + 1;
cyclic_pos -= ahead;
return true;
}
int get_match_pairs( Pair * pairs = 0 );
void update_distance_prices();
// move-to-front dis in/into reps; do nothing if( dis4 <= 0 )
static void mtf_reps( const int dis4, int reps[num_rep_distances] )
{
if( dis4 >= num_rep_distances ) // match
{
reps[3] = reps[2]; reps[2] = reps[1]; reps[1] = reps[0];
reps[0] = dis4 - num_rep_distances;
}
else if( dis4 > 0 ) // repeated match
{
const int distance = reps[dis4];
for( int i = dis4; i > 0; --i ) reps[i] = reps[i-1];
reps[0] = distance;
}
}
int price_shortrep( const State state, const int pos_state ) const
{
return price0( bm_rep0[state()] ) + price0( bm_len[state()][pos_state] );
}
int price_rep( const int rep, const State state, const int pos_state ) const
{
if( rep == 0 ) return price0( bm_rep0[state()] ) +
price1( bm_len[state()][pos_state] );
int price = price1( bm_rep0[state()] );
if( rep == 1 )
price += price0( bm_rep1[state()] );
else
{
price += price1( bm_rep1[state()] );
price += price_bit( bm_rep2[state()], rep - 2 );
}
return price;
}
int price_rep0_len( const int len, const State state, const int pos_state ) const
{
return price_rep( 0, state, pos_state ) +
rep_len_prices.price( len, pos_state );
}
int price_pair( const int dis, const int len, const int pos_state ) const
{
const int price = match_len_prices.price( len, pos_state );
const int len_state = get_len_state( len );
if( dis < modeled_distances )
return price + dis_prices[len_state][dis];
else
return price + dis_slot_prices[len_state][get_slot( dis )] +
align_prices[dis & (dis_align_size - 1)];
}
int read_match_distances()
{
const int num_pairs = get_match_pairs( pairs );
if( num_pairs > 0 )
{
const int len = pairs[num_pairs-1].len;
if( len == match_len_limit && len < max_match_len )
pairs[num_pairs-1].len =
true_match_len( len, pairs[num_pairs-1].dis + 1 );
}
return num_pairs;
}
void move_and_update( int n )
{
while( true )
{
move_pos();
if( --n <= 0 ) break;
get_match_pairs();
}
}
void backward( int cur )
{
int dis4 = trials[cur].dis4;
while( cur > 0 )
{
const int prev_index = trials[cur].prev_index;
Trial & prev_trial = trials[prev_index];
if( trials[cur].prev_index2 != single_step_trial )
{
prev_trial.dis4 = -1; // literal
prev_trial.prev_index = prev_index - 1;
prev_trial.prev_index2 = single_step_trial;
if( trials[cur].prev_index2 >= 0 )
{
Trial & prev_trial2 = trials[prev_index-1];
prev_trial2.dis4 = dis4; dis4 = 0; // rep0
prev_trial2.prev_index = trials[cur].prev_index2;
prev_trial2.prev_index2 = single_step_trial;
}
}
prev_trial.price = cur - prev_index; // len
cur = dis4; dis4 = prev_trial.dis4; prev_trial.dis4 = cur;
cur = prev_index;
}
}
int sequence_optimizer( const int reps[num_rep_distances],
const State state );
enum { before_size = max_num_trials,
// bytes to keep in buffer after pos
after_size = ( 2 * max_match_len ) + 1,
dict_factor = 2,
num_prev_positions3 = 1 << 16,
num_prev_positions2 = 1 << 10,
num_prev_positions23 = num_prev_positions2 + num_prev_positions3,
pos_array_factor = 2 };
public:
LZ_encoder( const int dict_size, const int len_limit,
const int ifd, const int outfd )
:
LZ_encoder_base( before_size, dict_size, after_size, dict_factor,
num_prev_positions23, pos_array_factor, ifd, outfd ),
cycles( ( len_limit < max_match_len ) ? 16 + ( len_limit / 2 ) : 256 ),
match_len_limit( len_limit ),
match_len_prices( match_len_model, match_len_limit ),
rep_len_prices( rep_len_model, match_len_limit ),
pending_num_pairs( 0 ),
num_dis_slots( 2 * real_bits( dictionary_size - 1 ) )
{
trials[1].prev_index = 0;
trials[1].prev_index2 = single_step_trial;
}
void reset()
{
LZ_encoder_base::reset();
match_len_prices.reset();
rep_len_prices.reset();
pending_num_pairs = 0;
}
bool encode_member( const unsigned long long member_size );
};