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Merging upstream version 1.1.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-20 15:04:13 +01:00
parent 67fe5d1941
commit de80b4cbe6
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
7 changed files with 104 additions and 91 deletions
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126
lzd.cc
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@ -1,5 +1,5 @@
/* Lzd - Educational decompressor for the lzip format
Copyright (C) 2013-2017 Antonio Diaz Diaz.
Copyright (C) 2013-2019 Antonio Diaz Diaz.
This program is free software. Redistribution and use in source and
binary forms, with or without modification, are permitted provided
@ -29,7 +29,7 @@
#include <cstring>
#include <stdint.h>
#include <unistd.h>
#if defined(__MSVCRT__) || defined(__OS2__) || defined(_MSC_VER)
#if defined(__MSVCRT__) || defined(__OS2__) || defined(__DJGPP__)
#include <fcntl.h>
#include <io.h>
#endif
@ -130,9 +130,9 @@ public:
const CRC32 crc32;
typedef uint8_t File_header[6]; // 0-3 magic, 4 version, 5 coded_dict_size
typedef uint8_t Lzip_header[6]; // 0-3 magic, 4 version, 5 coded_dict_size
typedef uint8_t File_trailer[20];
typedef uint8_t Lzip_trailer[20];
// 0-3 CRC32 of the uncompressed data
// 4-11 size of the uncompressed data
// 12-19 member size including header and trailer
@ -326,6 +326,7 @@ bool LZ_decoder::decode_member() // Returns false if error
const int pos_state = data_position() & pos_state_mask;
if( rdec.decode_bit( bm_match[state()][pos_state] ) == 0 ) // 1st bit
{
// literal byte
const uint8_t prev_byte = peek( 0 );
const int literal_state = prev_byte >> ( 8 - literal_context_bits );
Bit_model * const bm = bm_literal[literal_state];
@ -334,67 +335,66 @@ bool LZ_decoder::decode_member() // Returns false if error
else
put_byte( rdec.decode_matched( bm, peek( rep0 ) ) );
state.set_char();
continue;
}
else // match or repeated match
// match or repeated match
int len;
if( rdec.decode_bit( bm_rep[state()] ) != 0 ) // 2nd bit
{
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_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; }
}
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
{
unsigned distance;
if( rdec.decode_bit( bm_rep1[state()] ) == 0 ) // 4th bit
distance = rep1;
if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit
distance = rep2;
else
{
if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit
distance = rep2;
else
{ distance = rep3; rep3 = rep2; }
rep2 = rep1;
}
rep1 = rep0;
rep0 = distance;
{ distance = rep3; rep3 = rep2; }
rep2 = rep1;
}
state.set_rep();
len = min_match_len + rdec.decode_len( rep_len_model, pos_state );
rep1 = rep0;
rep0 = distance;
}
else // match
{
rep3 = rep2; rep2 = rep1; rep1 = rep0;
len = min_match_len + rdec.decode_len( match_len_model, pos_state );
const int len_state = std::min( len - min_match_len, len_states - 1 );
rep0 = rdec.decode_tree( bm_dis_slot[len_state], dis_slot_bits );
if( rep0 >= start_dis_model )
{
const unsigned dis_slot = rep0;
const int direct_bits = ( dis_slot >> 1 ) - 1;
rep0 = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
if( dis_slot < end_dis_model )
rep0 += rdec.decode_tree_reversed( bm_dis + ( rep0 - dis_slot ),
direct_bits );
else
{
rep0 += rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits;
rep0 += rdec.decode_tree_reversed( bm_align, dis_align_bits );
if( rep0 == 0xFFFFFFFFU ) // marker found
{
flush_data();
return ( len == min_match_len ); // End Of Stream marker
}
}
}
state.set_match();
if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) )
{ flush_data(); return false; }
}
for( int i = 0; i < len; ++i ) put_byte( peek( rep0 ) );
state.set_rep();
len = min_match_len + rdec.decode_len( rep_len_model, pos_state );
}
else // match
{
rep3 = rep2; rep2 = rep1; rep1 = rep0;
len = min_match_len + rdec.decode_len( match_len_model, pos_state );
const int len_state = std::min( len - min_match_len, len_states - 1 );
rep0 = rdec.decode_tree( bm_dis_slot[len_state], dis_slot_bits );
if( rep0 >= start_dis_model )
{
const unsigned dis_slot = rep0;
const int direct_bits = ( dis_slot >> 1 ) - 1;
rep0 = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
if( dis_slot < end_dis_model )
rep0 += rdec.decode_tree_reversed( bm_dis + ( rep0 - dis_slot ),
direct_bits );
else
{
rep0 += rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits;
rep0 += rdec.decode_tree_reversed( bm_align, dis_align_bits );
if( rep0 == 0xFFFFFFFFU ) // marker found
{
flush_data();
return ( len == min_match_len ); // End Of Stream marker
}
}
}
state.set_match();
if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) )
{ flush_data(); return false; }
}
for( int i = 0; i < len; ++i ) put_byte( peek( rep0 ) );
}
flush_data();
return false;
@ -412,7 +412,7 @@ int main( const int argc, const char * const argv[] )
"It is not safe to use lzd for any real work.\n"
"\nUsage: %s < file.lz > file\n", argv[0] );
std::printf( "Lzd decompresses from standard input to standard output.\n"
"\nCopyright (C) 2017 Antonio Diaz Diaz.\n"
"\nCopyright (C) 2019 Antonio Diaz Diaz.\n"
"This is free software: you are free to change and redistribute it.\n"
"There is NO WARRANTY, to the extent permitted by law.\n"
"Report bugs to lzip-bug@nongnu.org\n"
@ -420,14 +420,14 @@ int main( const int argc, const char * const argv[] )
return 0;
}
#if defined(__MSVCRT__) || defined(__OS2__) || defined(_MSC_VER)
setmode( fileno( stdin ), O_BINARY );
setmode( fileno( stdout ), O_BINARY );
#if defined(__MSVCRT__) || defined(__OS2__) || defined(__DJGPP__)
setmode( STDIN_FILENO, O_BINARY );
setmode( STDOUT_FILENO, O_BINARY );
#endif
for( bool first_member = true; ; first_member = false )
{
File_header header; // verify header
Lzip_header header; // verify header
for( int i = 0; i < 6; ++i ) header[i] = std::getc( stdin );
if( std::feof( stdin ) || std::memcmp( header, "LZIP\x01", 5 ) != 0 )
{
@ -446,7 +446,7 @@ int main( const int argc, const char * const argv[] )
if( !decoder.decode_member() )
{ std::fputs( "Data error\n", stderr ); return 2; }
File_trailer trailer; // verify trailer
Lzip_trailer trailer; // verify trailer
for( int i = 0; i < 20; ++i ) trailer[i] = std::getc( stdin );
unsigned crc = 0;
for( int i = 3; i >= 0; --i ) { crc <<= 8; crc += trailer[i]; }
@ -457,7 +457,7 @@ int main( const int argc, const char * const argv[] )
}
if( std::fclose( stdout ) != 0 )
{ std::fprintf( stderr, "Can't close stdout: %s\n", std::strerror( errno ) );
{ std::fprintf( stderr, "Error closing stdout: %s\n", std::strerror( errno ) );
return 1; }
return 0;
}