lzip/lziprecover
1
0
Fork 0
Code Issues Activity

Merging upstream version 1.22.

Browse source 
Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-21 11:31:04 +01:00
parent fb5506e101
commit e14dcad9bf
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
51 changed files with 4969 additions and 1988 deletions
Download patch file Download diff file Expand all files Collapse all files

90
decoder.h
View file

@ -1,18 +1,18 @@
/* Lziprecover - Data recovery tool for the lzip format
Copyright (C) 2009-2019 Antonio Diaz Diaz.
/* Lziprecover - Data recovery tool for the lzip format
Copyright (C) 2009-2021 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 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.
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/>.
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
@ -49,7 +49,9 @@ public:
unsigned get_code() const { return code; }
bool finished() { return pos >= stream_pos && !read_block(); }
unsigned long long member_position() const { return partial_member_pos + pos; }
unsigned long long member_position() const
{ return partial_member_pos + pos; }
void reset_member_position()
{ partial_member_pos = 0; partial_member_pos -= pos; }
@ -74,10 +76,40 @@ public:
return sz;
}
/* if ignore_errors, stop reading before the first wrong byte, so that
unreading the header is not required to sync to next member */
int read_header_carefully( Lzip_header & header, const bool ignore_errors )
{
int sz = 0;
while( sz < Lzip_header::size && !finished() )
{
header.data[sz] = buffer[pos];
if( ignore_errors &&
( ( sz < 4 && header.data[sz] != lzip_magic[sz] ) ||
( sz == 4 && !header.verify_version() ) ||
( sz == 5 && !isvalid_ds( header.dictionary_size() ) ) ) ) break;
++pos; ++sz;
}
return sz;
}
bool find_header( Lzip_header & header )
{
while( !finished() )
{
if( buffer[pos] != lzip_magic[0] ) { ++pos; continue; }
reset_member_position();
Lzip_header h;
if( read_header_carefully( h, true ) == Lzip_header::size )
{ header = h; return true; }
}
return false;
}
void load()
{
code = 0;
for( int i = 0; i < 5; ++i ) code = (code << 8) | get_byte();
for( int i = 0; i < 5; ++i ) code = ( code << 8 ) | get_byte();
range = 0xFFFFFFFFU;
code &= range; // make sure that first byte is discarded
}
@ -85,7 +117,7 @@ public:
void normalize()
{
if( range <= 0x00FFFFFFU )
{ range <<= 8; code = (code << 8) | get_byte(); }
{ range <<= 8; code = ( code << 8 ) | get_byte(); }
}
unsigned decode( const int num_bits )
@ -98,7 +130,7 @@ public:
// symbol <<= 1;
// if( code >= range ) { code -= range; symbol |= 1; }
const bool bit = ( code >= range );
symbol = ( symbol << 1 ) + bit;
symbol <<= 1; symbol += bit;
code -= range & ( 0U - bit );
}
return symbol;
@ -111,7 +143,8 @@ public:
if( code < bound )
{
range = bound;
bm.probability += (bit_model_total - bm.probability) >> bit_model_move_bits;
bm.probability +=
( bit_model_total - bm.probability ) >> bit_model_move_bits;
return 0;
}
else
@ -125,8 +158,7 @@ public:
unsigned decode_tree3( Bit_model bm[] )
{
unsigned symbol = 1;
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
unsigned symbol = 2 | decode_bit( bm[1] );
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
return symbol & 7;
@ -134,8 +166,7 @@ public:
unsigned decode_tree6( Bit_model bm[] )
{
unsigned symbol = 1;
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
unsigned symbol = 2 | decode_bit( bm[1] );
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
@ -159,7 +190,7 @@ public:
for( int i = 0; i < num_bits; ++i )
{
const unsigned bit = decode_bit( bm[model] );
model = ( model << 1 ) + bit;
model <<= 1; model += bit;
symbol |= ( bit << i );
}
return symbol;
@ -168,12 +199,9 @@ public:
unsigned decode_tree_reversed4( Bit_model bm[] )
{
unsigned symbol = decode_bit( bm[1] );
unsigned model = 2 + symbol;
unsigned bit = decode_bit( bm[model] );
model = ( model << 1 ) + bit; symbol |= ( bit << 1 );
bit = decode_bit( bm[model] );
model = ( model << 1 ) + bit; symbol |= ( bit << 2 );
symbol |= ( decode_bit( bm[model] ) << 3 );
symbol += decode_bit( bm[2+symbol] ) << 1;
symbol += decode_bit( bm[4+symbol] ) << 2;
symbol += decode_bit( bm[8+symbol] ) << 3;
return symbol;
}
@ -184,9 +212,9 @@ public:
while( symbol < 0x100 )
{
const unsigned match_bit = ( match_byte <<= 1 ) & 0x100;
const unsigned bit = decode_bit( bm1[match_bit+symbol] );
symbol = ( symbol << 1 ) | bit;
if( match_bit != bit << 8 )
const bool bit = decode_bit( bm1[symbol+match_bit] );
symbol <<= 1; symbol |= bit;
if( match_bit >> 8 != bit )
{
while( symbol < 0x100 )
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );