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Merging upstream version 1.9.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-20 21:23:49 +01:00
parent 0ec09957eb
commit 1ee0d26241
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
30 changed files with 861 additions and 1188 deletions
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84
fast_encoder.c
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@ -1,28 +1,20 @@
/* Lzlib - Compression library for the lzip format
Copyright (C) 2009-2016 Antonio Diaz Diaz.
Copyright (C) 2009-2017 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
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This library is free software. Redistribution and use in source and
binary forms, with or without modification, are permitted provided
that the following conditions are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
This library 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 library. If not, see <http://www.gnu.org/licenses/>.
As a special exception, you may use this file as part of a free
software library without restriction. Specifically, if other files
instantiate templates or use macros or inline functions from this
file, or you compile this file and link it with other files to
produce an executable, this file does not by itself cause the
resulting executable to be covered by the GNU General Public
License. This exception does not however invalidate any other
reasons why the executable file might be covered by the GNU General
Public License.
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*/
int FLZe_longest_match_len( struct FLZ_encoder * const fe, int * const distance )
@ -30,21 +22,22 @@ int FLZe_longest_match_len( struct FLZ_encoder * const fe, int * const distance
enum { len_limit = 16 };
const uint8_t * const data = Mb_ptr_to_current_pos( &fe->eb.mb );
int32_t * ptr0 = fe->eb.mb.pos_array + fe->eb.mb.cyclic_pos;
int32_t * newptr;
const int pos1 = fe->eb.mb.pos + 1;
int maxlen = 0;
int count, delta, newpos;
if( len_limit > Mb_available_bytes( &fe->eb.mb ) ) { *ptr0 = 0; return 0; }
int maxlen = 0, newpos1, count;
const int available = min( Mb_available_bytes( &fe->eb.mb ), max_match_len );
if( available < len_limit ) { *ptr0 = 0; return 0; }
fe->key4 = ( ( fe->key4 << 4 ) ^ data[3] ) & fe->eb.mb.key4_mask;
newpos = fe->eb.mb.prev_positions[fe->key4];
newpos1 = fe->eb.mb.prev_positions[fe->key4];
fe->eb.mb.prev_positions[fe->key4] = pos1;
for( count = 4; ; )
{
if( --count < 0 || newpos <= 0 ) { *ptr0 = 0; break; }
delta = pos1 - newpos;
if( delta > fe->eb.mb.dictionary_size ) { *ptr0 = 0; break; }
int32_t * newptr;
int delta;
if( newpos1 <= 0 || --count < 0 ||
( delta = pos1 - newpos1 ) > fe->eb.mb.dictionary_size )
{ *ptr0 = 0; break; }
newptr = fe->eb.mb.pos_array +
( fe->eb.mb.cyclic_pos - delta +
( ( fe->eb.mb.cyclic_pos >= delta ) ? 0 : fe->eb.mb.dictionary_size + 1 ) );
@ -52,23 +45,15 @@ int FLZe_longest_match_len( struct FLZ_encoder * const fe, int * const distance
if( data[maxlen-delta] == data[maxlen] )
{
int len = 0;
while( len < len_limit && data[len-delta] == data[len] ) ++len;
if( maxlen < len ) { maxlen = len; *distance = delta - 1; }
while( len < available && data[len-delta] == data[len] ) ++len;
if( maxlen < len )
{ maxlen = len; *distance = delta - 1;
if( maxlen >= len_limit ) { *ptr0 = *newptr; break; } }
}
if( maxlen < len_limit )
{
*ptr0 = newpos;
ptr0 = newptr;
newpos = *ptr0;
}
else
{
*ptr0 = *newptr;
maxlen += Mb_true_match_len( &fe->eb.mb, maxlen, *distance + 1,
max_match_len - maxlen );
break;
}
*ptr0 = newpos1;
ptr0 = newptr;
newpos1 = *ptr0;
}
return maxlen;
}
@ -81,10 +66,7 @@ bool FLZe_encode_member( struct FLZ_encoder * const fe )
if( fe->eb.member_finished ) return true;
if( Re_member_position( &fe->eb.renc ) >= fe->eb.member_size_limit )
{
if( LZeb_full_flush( &fe->eb ) ) fe->eb.member_finished = true;
return true;
}
{ LZeb_try_full_flush( &fe->eb ); return true; }
if( Mb_data_position( &fe->eb.mb ) == 0 &&
!Mb_data_finished( &fe->eb.mb ) ) /* encode first byte */
@ -105,7 +87,8 @@ bool FLZe_encode_member( struct FLZ_encoder * const fe )
Re_member_position( &fe->eb.renc ) < fe->eb.member_size_limit )
{
int match_distance;
int main_len, pos_state, len = 0;
int main_len, pos_state;
int len = 0;
if( !Mb_enough_available_bytes( &fe->eb.mb ) ||
!Re_enough_free_bytes( &fe->eb.renc ) ) return true;
main_len = FLZe_longest_match_len( fe, &match_distance );
@ -113,8 +96,7 @@ bool FLZe_encode_member( struct FLZ_encoder * const fe )
for( i = 0; i < num_rep_distances; ++i )
{
const int tlen = Mb_true_match_len( &fe->eb.mb, 0,
fe->eb.reps[i] + 1, max_match_len );
const int tlen = Mb_true_match_len( &fe->eb.mb, 0, fe->eb.reps[i] + 1 );
if( tlen > len ) { len = tlen; rep = i; }
}
if( len > min_match_len && len + 3 > main_len )
@ -195,6 +177,6 @@ bool FLZe_encode_member( struct FLZ_encoder * const fe )
}
}
if( LZeb_full_flush( &fe->eb ) ) fe->eb.member_finished = true;
LZeb_try_full_flush( &fe->eb );
return true;
}