lzip/lzd
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Merging upstream version 1.4.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-20 15:08:50 +01:00
parent d5fbfe6549
commit 5a79dbf791
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
8 changed files with 79 additions and 88 deletions
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55
lzd.cc
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@ -1,5 +1,5 @@
/* Lzd - Educational decompressor for the lzip format
Copyright (C) 2013-2022 Antonio Diaz Diaz.
Copyright (C) 2013-2024 Antonio Diaz Diaz.
This program is free software. Redistribution and use in source and
binary forms, with or without modification, are permitted provided
@ -18,7 +18,7 @@
*/
/*
Exit status: 0 for a normal exit, 1 for environmental problems
(file not found, invalid command line options, I/O errors, etc), 2 to
(file not found, invalid command-line options, I/O errors, etc), 2 to
indicate a corrupt or invalid input file.
*/
@ -130,10 +130,11 @@ public:
const CRC32 crc32;
typedef uint8_t Lzip_header[6]; // 0-3 magic bytes
// 4 version
// 5 coded dictionary size
typedef uint8_t Lzip_trailer[20];
enum { header_size = 6, trailer_size = 20 };
typedef uint8_t Lzip_header[header_size]; // 0-3 magic bytes
// 4 version
// 5 coded dictionary size
typedef uint8_t Lzip_trailer[trailer_size];
// 0-3 CRC32 of the uncompressed data
// 4-11 size of the uncompressed data
// 12-19 member size including header and trailer
@ -145,7 +146,8 @@ class Range_decoder
uint32_t range;
public:
Range_decoder() : member_pos( 6 ), code( 0 ), range( 0xFFFFFFFFU )
Range_decoder()
: member_pos( header_size ), code( 0 ), range( 0xFFFFFFFFU )
{
get_byte(); // discard first byte of the LZMA stream
for( int i = 0; i < 4; ++i ) code = ( code << 8 ) | get_byte();
@ -168,9 +170,9 @@ public:
return symbol;
}
unsigned decode_bit( Bit_model & bm )
bool decode_bit( Bit_model & bm )
{
unsigned symbol;
bool symbol;
const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
if( code < bound )
{
@ -216,8 +218,8 @@ public:
unsigned symbol = 1;
for( int i = 7; i >= 0; --i )
{
const unsigned match_bit = ( match_byte >> i ) & 1;
const unsigned bit = decode_bit( bm[symbol+(match_bit<<8)+0x100] );
const bool match_bit = ( match_byte >> i ) & 1;
const bool bit = decode_bit( bm[symbol+(match_bit<<8)+0x100] );
symbol = ( symbol << 1 ) | bit;
if( match_bit != bit )
{
@ -232,11 +234,12 @@ public:
unsigned decode_len( Len_model & lm, const int pos_state )
{
if( decode_bit( lm.choice1 ) == 0 )
return decode_tree( lm.bm_low[pos_state], len_low_bits );
return min_match_len +
decode_tree( lm.bm_low[pos_state], len_low_bits );
if( decode_bit( lm.choice2 ) == 0 )
return len_low_symbols +
return min_match_len + len_low_symbols +
decode_tree( lm.bm_mid[pos_state], len_mid_bits );
return len_low_symbols + len_mid_symbols +
return min_match_len + len_low_symbols + len_mid_symbols +
decode_tree( lm.bm_high, len_high_bits );
}
};
@ -371,12 +374,12 @@ bool LZ_decoder::decode_member() // Return false if error
rep0 = distance;
}
state.set_rep();
len = min_match_len + rdec.decode_len( rep_len_model, pos_state );
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 );
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 )
@ -395,7 +398,7 @@ bool LZ_decoder::decode_member() // Return false if error
if( rep0 == 0xFFFFFFFFU ) // marker found
{
flush_data();
return ( len == min_match_len ); // End Of Stream marker
return len == min_match_len; // End Of Stream marker
}
}
}
@ -420,10 +423,10 @@ int main( const int argc, const char * const argv[] )
"See the lzip manual for an explanation of the code.\n"
"\nUsage: %s [-d] < file.lz > file\n"
"Lzd decompresses from standard input to standard output.\n"
"\nCopyright (C) 2022 Antonio Diaz Diaz.\n"
"\nCopyright (C) 2024 Antonio Diaz Diaz.\n"
"License 2-clause BSD.\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"
"This is free software: you are free to change and redistribute "
"it.\nThere is NO WARRANTY, to the extent permitted by law.\n"
"Report bugs to lzip-bug@nongnu.org\n"
"Lzd home page: http://www.nongnu.org/lzip/lzd.html\n",
PROGVERSION, argv[0] );
@ -437,8 +440,8 @@ int main( const int argc, const char * const argv[] )
for( bool first_member = true; ; first_member = false )
{
Lzip_header header; // verify header
for( int i = 0; i < 6; ++i ) header[i] = std::getc( stdin );
Lzip_header header; // check header
for( int i = 0; i < header_size; ++i ) header[i] = std::getc( stdin );
if( std::feof( stdin ) || std::memcmp( header, "LZIP\x01", 5 ) != 0 )
{
if( first_member )
@ -449,15 +452,15 @@ int main( const int argc, const char * const argv[] )
unsigned dict_size = 1 << ( header[5] & 0x1F );
dict_size -= ( dict_size / 16 ) * ( ( header[5] >> 5 ) & 7 );
if( dict_size < min_dictionary_size || dict_size > max_dictionary_size )
{ std::fputs( "Invalid dictionary size in member header.\n", stderr );
return 2; }
{ std::fputs( "Invalid dictionary size in member header.\n",
stderr ); return 2; }
LZ_decoder decoder( dict_size ); // decode LZMA stream
if( !decoder.decode_member() )
{ std::fputs( "Data error\n", stderr ); return 2; }
Lzip_trailer trailer; // verify trailer
for( int i = 0; i < 20; ++i ) trailer[i] = decoder.get_byte();
Lzip_trailer trailer; // check trailer
for( int i = 0; i < trailer_size; ++i ) trailer[i] = decoder.get_byte();
int retval = 0;
unsigned crc = 0;
for( int i = 3; i >= 0; --i ) crc = ( crc << 8 ) + trailer[i];