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Merging upstream version 1.0.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-20 15:01:50 +01:00
parent fa46c2beb5
commit 57a6b04c20
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
10 changed files with 124 additions and 74 deletions
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17
COPYING Normal file
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@ -0,0 +1,17 @@
Lzd - Educational decompressor for the lzip format
Copyright (C) Antonio Diaz Diaz.
This program 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 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.

8
ChangeLog
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@ -1,3 +1,9 @@
2017-05-02 Antonio Diaz Diaz <antonio@gnu.org>
* Version 1.0 released.
* lzd.cc: Minor code improvements.
* testsuite/check.sh: A POSIX shell is required to run the tests.
2016-05-10 Antonio Diaz Diaz <antonio@gnu.org>
* Version 0.9 released.
@ -43,7 +49,7 @@
* Version 0.1 released.
Copyright (C) 2013-2016 Antonio Diaz Diaz.
Copyright (C) 2013-2017 Antonio Diaz Diaz.
This file is a collection of facts, and thus it is not copyrightable,
but just in case, you have unlimited permission to copy, distribute and

2
INSTALL
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@ -50,7 +50,7 @@ After running 'configure', you can run 'make' and 'make install' as
explained above.
Copyright (C) 2013-2016 Antonio Diaz Diaz.
Copyright (C) 2013-2017 Antonio Diaz Diaz.
This file is free documentation: you have unlimited permission to copy,
distribute and modify it.

5
Makefile.in
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@ -95,16 +95,17 @@ dist : doc
ln -sf $(VPATH) $(DISTNAME)
tar -Hustar --owner=root --group=root -cvf $(DISTNAME).tar \
$(DISTNAME)/AUTHORS \
$(DISTNAME)/COPYING \
$(DISTNAME)/ChangeLog \
$(DISTNAME)/INSTALL \
$(DISTNAME)/Makefile.in \
$(DISTNAME)/NEWS \
$(DISTNAME)/README \
$(DISTNAME)/configure \
$(DISTNAME)/*.cc \
$(DISTNAME)/testsuite/check.sh \
$(DISTNAME)/testsuite/test.txt \
$(DISTNAME)/testsuite/test.txt.lz \
$(DISTNAME)/*.cc
$(DISTNAME)/testsuite/test.txt.lz
rm -f $(DISTNAME)
lzip -v -9 $(DISTNAME).tar

7
NEWS
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@ -1,4 +1,5 @@
Changes in version 0.9:
Changes in version 1.0:
A configure warning happening on some shells when testing for g++ has
been fixed.
Minor code improvements have been made.
The tests have been improved.

12
README
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@ -24,11 +24,11 @@ availability:
merging of damaged copies of a file.
* The lzip format is as simple as possible (but not simpler). The
lzip manual provides the code of a simple decompressor along with a
detailed explanation of how it works, so that with the only help of
the lzip manual it would be possible for a digital archaeologist to
extract the data from a lzip file long after quantum computers
eventually render LZMA obsolete.
lzip manual provides the source code of a simple decompressor along
with a detailed explanation of how it works, so that with the only
help of the lzip manual it would be possible for a digital
archaeologist to extract the data from a lzip file long after
quantum computers eventually render LZMA obsolete.
* Additionally the lzip reference implementation is copylefted, which
guarantees that it will remain free forever.
@ -45,7 +45,7 @@ range encoding), and Igor Pavlov (for putting all the above together in
LZMA).
Copyright (C) 2013-2016 Antonio Diaz Diaz.
Copyright (C) 2013-2017 Antonio Diaz Diaz.
This file is free documentation: you have unlimited permission to copy,
distribute and modify it.

21
configure vendored
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@ -1,12 +1,12 @@
#! /bin/sh
# configure script for Lzd - Educational decompressor for the lzip format
# Copyright (C) 2013-2016 Antonio Diaz Diaz.
# Copyright (C) 2013-2017 Antonio Diaz Diaz.
#
# This configure script is free software: you have unlimited permission
# to copy, distribute and modify it.
pkgname=lzd
pkgversion=0.9
pkgversion=1.0
progname=lzd
srctrigger=lzd.cc
@ -26,11 +26,11 @@ CXXFLAGS='-Wall -W -O2'
LDFLAGS=
# checking whether we are using GNU C++.
if /bin/sh -c "${CXX} --version" > /dev/null 2>&1 ; then true
else
/bin/sh -c "${CXX} --version" > /dev/null 2>&1 ||
{
CXX=c++
CXXFLAGS='-W -O2'
fi
CXXFLAGS=-O2
}
# Loop over all args
args=
@ -52,9 +52,12 @@ while [ $# != 0 ] ; do
# Process the options
case ${option} in
--help | -h)
echo "Usage: configure [options]"
echo "Usage: $0 [OPTION]... [VAR=VALUE]..."
echo
echo "Options: [defaults in brackets]"
echo "To assign makefile variables (e.g., CXX, CXXFLAGS...), specify them as"
echo "arguments to configure in the form VAR=VALUE."
echo
echo "Options and variables: [defaults in brackets]"
echo " -h, --help display this help and exit"
echo " -V, --version output version information and exit"
echo " --srcdir=DIR find the sources in DIR [. or ..]"
@ -165,7 +168,7 @@ echo "LDFLAGS = ${LDFLAGS}"
rm -f Makefile
cat > Makefile << EOF
# Makefile for Lzd - Educational decompressor for the lzip format
# Copyright (C) 2013-2016 Antonio Diaz Diaz.
# Copyright (C) 2013-2017 Antonio Diaz Diaz.
# This file was generated automatically by configure. Don't edit.
#
# This Makefile is free software: you have unlimited permission

78
lzd.cc
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@ -1,5 +1,5 @@
/* Lzd - Educational decompressor for the lzip format
Copyright (C) 2013-2016 Antonio Diaz Diaz.
Copyright (C) 2013-2017 Antonio Diaz Diaz.
This program is free software. Redistribution and use in source and
binary forms, with or without modification, are permitted provided
@ -150,10 +150,10 @@ public:
uint8_t get_byte() { return std::getc( stdin ); }
int decode( const int num_bits )
unsigned decode( const int num_bits )
{
int symbol = 0;
for( int i = 0; i < num_bits; ++i )
unsigned symbol = 0;
for( int i = num_bits; i > 0; --i )
{
range >>= 1;
symbol <<= 1;
@ -164,9 +164,9 @@ public:
return symbol;
}
int decode_bit( Bit_model & bm )
unsigned decode_bit( Bit_model & bm )
{
int symbol;
unsigned symbol;
const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
if( code < bound )
{
@ -186,18 +186,18 @@ public:
return symbol;
}
int decode_tree( Bit_model bm[], const int num_bits )
unsigned decode_tree( Bit_model bm[], const int num_bits )
{
int symbol = 1;
unsigned symbol = 1;
for( int i = 0; i < num_bits; ++i )
symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
return symbol - (1 << num_bits);
}
int decode_tree_reversed( Bit_model bm[], const int num_bits )
unsigned decode_tree_reversed( Bit_model bm[], const int num_bits )
{
int symbol = decode_tree( bm, num_bits );
int reversed_symbol = 0;
unsigned symbol = decode_tree( bm, num_bits );
unsigned reversed_symbol = 0;
for( int i = 0; i < num_bits; ++i )
{
reversed_symbol = ( reversed_symbol << 1 ) | ( symbol & 1 );
@ -206,14 +206,13 @@ public:
return reversed_symbol;
}
int decode_matched( Bit_model bm[], const int match_byte )
unsigned decode_matched( Bit_model bm[], const unsigned match_byte )
{
Bit_model * const bm1 = bm + 0x100;
int symbol = 1;
unsigned symbol = 1;
for( int i = 7; i >= 0; --i )
{
const int match_bit = ( match_byte >> i ) & 1;
const int bit = decode_bit( bm1[(match_bit<<8)+symbol] );
const unsigned match_bit = ( match_byte >> i ) & 1;
const unsigned bit = decode_bit( bm[symbol+(match_bit<<8)+0x100] );
symbol = ( symbol << 1 ) | bit;
if( match_bit != bit )
{
@ -225,7 +224,7 @@ public:
return symbol & 0xFF;
}
int decode_len( Len_model & lm, const int pos_state )
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 );
@ -253,9 +252,9 @@ class LZ_decoder
uint8_t peek( const unsigned distance ) const
{
unsigned i = pos - distance - 1;
if( pos <= distance ) i += dictionary_size;
return buffer[i];
if( pos > distance ) return buffer[pos - distance - 1];
if( pos_wrapped ) return buffer[dictionary_size + pos - distance - 1];
return 0; // prev_byte of first byte
}
void put_byte( const uint8_t b )
@ -274,7 +273,7 @@ public:
stream_pos( 0 ),
crc_( 0xFFFFFFFFU ),
pos_wrapped( false )
{ buffer[dictionary_size-1] = 0; } // prev_byte of first byte
{}
~LZ_decoder() { delete[] buffer; }
@ -312,13 +311,13 @@ bool LZ_decoder::decode_member() // Returns false if error
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];
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 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;
@ -341,7 +340,12 @@ bool LZ_decoder::decode_member() // Returns false if error
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; }
}
else
{
unsigned distance;
if( rdec.decode_bit( bm_rep1[state()] ) == 0 ) // 4th bit
@ -357,11 +361,6 @@ bool LZ_decoder::decode_member() // Returns false if error
rep1 = rep0;
rep0 = distance;
}
else
{
if( rdec.decode_bit( bm_len[state()][pos_state] ) == 0 ) // 4th bit
{ state.set_short_rep(); put_byte( peek( rep0 ) ); continue; }
}
state.set_rep();
len = min_match_len + rdec.decode_len( rep_len_model, pos_state );
}
@ -370,15 +369,14 @@ bool LZ_decoder::decode_member() // Returns false if error
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 );
const int dis_slot =
rdec.decode_tree( bm_dis_slot[len_state], dis_slot_bits );
if( dis_slot < start_dis_model ) rep0 = dis_slot;
else
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 - 1,
rep0 += rdec.decode_tree_reversed( bm_dis + ( rep0 - dis_slot ),
direct_bits );
else
{
@ -414,7 +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) 2016 Antonio Diaz Diaz.\n"
"\nCopyright (C) 2017 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"
@ -429,7 +427,7 @@ int main( const int argc, const char * const argv[] )
for( bool first_member = true; ; first_member = false )
{
File_header header;
File_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 )
{
@ -444,11 +442,11 @@ int main( const int argc, const char * const argv[] )
{ std::fputs( "Invalid dictionary size in member header.\n", stderr );
return 2; }
LZ_decoder decoder( dict_size );
LZ_decoder decoder( dict_size ); // decode LZMA stream
if( !decoder.decode_member() )
{ std::fputs( "Data error\n", stderr ); return 2; }
File_trailer trailer;
File_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]; }

48
testsuite/check.sh
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@ -1,6 +1,6 @@
#! /bin/sh
# check script for Lzd - Educational decompressor for lzip files
# Copyright (C) 2013-2016 Antonio Diaz Diaz.
# Copyright (C) 2013-2017 Antonio Diaz Diaz.
#
# This script is free software: you have unlimited permission
# to copy, distribute and modify it.
@ -17,6 +17,13 @@ if [ ! -f "${LZIP}" ] || [ ! -x "${LZIP}" ] ; then
exit 1
fi
[ -e "${LZIP}" ] 2> /dev/null ||
{
echo "$0: a POSIX shell is required to run the tests"
echo "Try bash -c \"$0 $1 $2\""
exit 1
}
if [ -d tmp ] ; then rm -rf tmp ; fi
mkdir tmp
cd "${objdir}"/tmp || framework_failure
@ -24,24 +31,41 @@ cd "${objdir}"/tmp || framework_failure
in="${testdir}"/test.txt
in_lz="${testdir}"/test.txt.lz
fail=0
test_failed() { fail=1 ; printf " $1" ; [ -z "$2" ] || printf "($2)" ; }
printf "testing lzd-%s..." "$2"
"${LZIP}" < "${in}" 2> /dev/null
if [ $? = 2 ] ; then printf . ; else printf - ; fail=1 ; fi
dd if="${in_lz}" bs=1 count=6 2> /dev/null | "${LZIP}" 2> /dev/null
if [ $? = 2 ] ; then printf . ; else printf - ; fail=1 ; fi
dd if="${in_lz}" bs=1 count=20 2> /dev/null | "${LZIP}" > /dev/null 2>&1
if [ $? = 2 ] ; then printf . ; else printf - ; fail=1 ; fi
[ $? = 2 ] || test_failed $LINENO
"${LZIP}" < "${in_lz}" > copy || fail=1
cmp "${in}" copy || fail=1
printf .
"${LZIP}" < "${in_lz}" > copy || test_failed $LINENO
cmp "${in}" copy || test_failed $LINENO
cat "${in}" "${in}" > in2 || framework_failure
cat "${in_lz}" "${in_lz}" | "${LZIP}" > copy2 || fail=1
cmp in2 copy2 || fail=1
printf .
cat "${in_lz}" "${in_lz}" > in2.lz || framework_failure
"${LZIP}" < in2.lz > copy2 || test_failed $LINENO
cmp in2 copy2 || test_failed $LINENO
printf "\ntesting bad input..."
cat "${in_lz}" "${in_lz}" "${in_lz}" > in3.lz || framework_failure
if dd if=in3.lz of=trunc.lz bs=14752 count=1 2> /dev/null &&
[ -e trunc.lz ] && cmp in2.lz trunc.lz > /dev/null 2>&1 ; then
# can't detect truncated header of non-first member
for i in 6 20 14734 14758 ; do
dd if=in3.lz of=trunc.lz bs=$i count=1 2> /dev/null
"${LZIP}" < trunc.lz > out 2> /dev/null
[ $? = 2 ] || test_failed $LINENO $i
done
else
printf "\nwarning: skipping truncation test: 'dd' does not work on your system."
fi
cat "${in_lz}" > ingin.lz || framework_failure
printf "g" >> ingin.lz || framework_failure
cat "${in_lz}" >> ingin.lz || framework_failure
"${LZIP}" < ingin.lz > copy || test_failed $LINENO
cmp "${in}" copy || test_failed $LINENO
echo
if [ ${fail} = 0 ] ; then

BIN
testsuite/test.txt.lz
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