diff options
Diffstat (limited to '')
-rw-r--r-- | AUTHORS | 7 | ||||
-rw-r--r-- | ChangeLog | 10 | ||||
-rw-r--r-- | INSTALL | 60 | ||||
-rw-r--r-- | Makefile.in | 104 | ||||
-rw-r--r-- | NEWS | 3 | ||||
-rw-r--r-- | README | 29 | ||||
-rwxr-xr-x | configure | 175 | ||||
-rw-r--r-- | decoder.cc | 363 | ||||
-rw-r--r-- | main.cc | 114 | ||||
-rwxr-xr-x | testsuite/check.sh | 43 | ||||
-rw-r--r-- | testsuite/test.txt | 676 | ||||
-rw-r--r-- | testsuite/test.txt.lz | bin | 0 -> 11518 bytes |
12 files changed, 1584 insertions, 0 deletions
@@ -0,0 +1,7 @@ +Lzd was written by Antonio Diaz Diaz. + +The ideas embodied in lzd are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for +the definition of Markov chains), G.N.N. Martin (for the definition of +range encoding), and Igor Pavlov (for putting all the above together in +LZMA). diff --git a/ChangeLog b/ChangeLog new file mode 100644 index 0000000..3a64682 --- /dev/null +++ b/ChangeLog @@ -0,0 +1,10 @@ +2013-03-21 Antonio Diaz Diaz <ant_diaz@teleline.es> + + * Version 0.1 released. + + +Copyright (C) 2013 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 +modify it. @@ -0,0 +1,60 @@ +Requirements +------------ +You will need a C++ compiler. +I use gcc 4.7.2 and 3.3.6, but the code should compile with any +standards compliant compiler. +Gcc is available at http://gcc.gnu.org. + + +Procedure +--------- +1. Unpack the archive if you have not done so already: + + lzip -cd lzip[version].tar.lz | tar -xf - +or + gzip -cd lzip[version].tar.gz | tar -xf - + +This creates the directory ./lzip[version] containing the source from +the main archive. + +2. Change to lzip directory and run configure. + (Try 'configure --help' for usage instructions). + + cd lzip[version] + ./configure + +3. Run make. + + make + +4. Optionally, type 'make check' to run the tests that come with lzip. + +5. Type 'make install' to install the program and any data files and + documentation. + + You can install only the program, the info manual or the man page + typing 'make install-bin', 'make install-info' or 'make install-man' + respectively. + + +Another way +----------- +You can also compile lzip into a separate directory. To do this, you +must use a version of 'make' that supports the 'VPATH' variable, such +as GNU 'make'. 'cd' to the directory where you want the object files +and executables to go and run the 'configure' script. 'configure' +automatically checks for the source code in '.', in '..' and in the +directory that 'configure' is in. + +'configure' recognizes the option '--srcdir=DIR' to control where to +look for the sources. Usually 'configure' can determine that directory +automatically. + +After running 'configure', you can run 'make' and 'make install' as +explained above. + + +Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz. + +This file is free documentation: you have unlimited permission to copy, +distribute and modify it. diff --git a/Makefile.in b/Makefile.in new file mode 100644 index 0000000..d313f51 --- /dev/null +++ b/Makefile.in @@ -0,0 +1,104 @@ + +DISTNAME = $(pkgname)-$(pkgversion) +INSTALL = install +INSTALL_PROGRAM = $(INSTALL) -p -m 755 +INSTALL_DATA = $(INSTALL) -p -m 644 +INSTALL_DIR = $(INSTALL) -d -m 755 +SHELL = /bin/sh + +objs = main.o + + +.PHONY : all install install-bin install-info install-man install-strip \ + uninstall uninstall-bin uninstall-info uninstall-man \ + doc info man check dist clean distclean + +all : $(progname) + +$(progname) : $(objs) + $(CXX) $(LDFLAGS) -o $@ $(objs) + +$(progname)_profiled : $(objs) + $(CXX) $(LDFLAGS) -pg -o $@ $(objs) + +main.o : main.cc + $(CXX) $(CPPFLAGS) $(CXXFLAGS) -DPROGVERSION=\"$(pkgversion)\" -c -o $@ $< + +%.o : %.cc + $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $< + +$(objs) : Makefile +main.o : decoder.cc + + +doc : + +info : $(VPATH)/doc/$(pkgname).info + +$(VPATH)/doc/$(pkgname).info : $(VPATH)/doc/$(pkgname).texinfo + cd $(VPATH)/doc && makeinfo $(pkgname).texinfo + +man : $(VPATH)/doc/$(progname).1 + +$(VPATH)/doc/$(progname).1 : $(progname) + help2man -n 'educational decompressor for lzip files' \ + -o $@ --no-info ./$(progname) + +Makefile : $(VPATH)/configure $(VPATH)/Makefile.in + ./config.status + +check : all + @$(VPATH)/testsuite/check.sh $(VPATH)/testsuite $(pkgversion) + +install : install-bin + +install-bin : all + if [ ! -d "$(DESTDIR)$(bindir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(bindir)" ; fi + $(INSTALL_PROGRAM) ./$(progname) "$(DESTDIR)$(bindir)/$(progname)" + +install-info : + if [ ! -d "$(DESTDIR)$(infodir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(infodir)" ; fi + $(INSTALL_DATA) $(VPATH)/doc/$(pkgname).info "$(DESTDIR)$(infodir)/$(pkgname).info" + -install-info --info-dir="$(DESTDIR)$(infodir)" "$(DESTDIR)$(infodir)/$(pkgname).info" + +install-man : + if [ ! -d "$(DESTDIR)$(mandir)/man1" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1" ; fi + $(INSTALL_DATA) $(VPATH)/doc/$(progname).1 "$(DESTDIR)$(mandir)/man1/$(progname).1" + +install-strip : all + $(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' install + +uninstall : uninstall-bin uninstall-info uninstall-man + +uninstall-bin : + -rm -f "$(DESTDIR)$(bindir)/$(progname)" + +uninstall-info : + -install-info --info-dir="$(DESTDIR)$(infodir)" --remove "$(DESTDIR)$(infodir)/$(pkgname).info" + -rm -f "$(DESTDIR)$(infodir)/$(pkgname).info" + +uninstall-man : + -rm -f "$(DESTDIR)$(mandir)/man1/$(progname).1" + +dist : doc + ln -sf $(VPATH) $(DISTNAME) + tar -cvf $(DISTNAME).tar \ + $(DISTNAME)/AUTHORS \ + $(DISTNAME)/ChangeLog \ + $(DISTNAME)/INSTALL \ + $(DISTNAME)/Makefile.in \ + $(DISTNAME)/NEWS \ + $(DISTNAME)/README \ + $(DISTNAME)/configure \ + $(DISTNAME)/testsuite/check.sh \ + $(DISTNAME)/testsuite/test.txt \ + $(DISTNAME)/testsuite/test.txt.lz \ + $(DISTNAME)/*.cc + rm -f $(DISTNAME) + lzip -v -9 $(DISTNAME).tar + +clean : + -rm -f $(progname) $(progname)_profiled $(objs) + +distclean : clean + -rm -f Makefile config.status *.tar *.tar.lz @@ -0,0 +1,3 @@ +Changes in version 0.1: + +Initial release. @@ -0,0 +1,29 @@ +Description + +Lzd is a very simplified decompressor for lzip files with an educational +purpose. Studying its source is a good first step to understand how lzip +works. It is not safe to use lzd for any real work. + +The source of lzd is also used in the lzip manual as a reference +decompressor in the description of the lzip file format. + +Lzd decompresses from standard input to standard output. Lzd will +correctly decompress the concatenation of two or more compressed files. +The result is the concatenation of the corresponding decompressed data. +Integrity of such concatenated compressed input is also verified. + +The ideas embodied in lzd are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for +the definition of Markov chains), G.N.N. Martin (for the definition of +range encoding), and Igor Pavlov (for putting all the above together in +LZMA). + + +Copyright (C) 2013 Antonio Diaz Diaz. + +This file is free documentation: you have unlimited permission to copy, +distribute and modify it. + +The file Makefile.in is a data file used by configure to produce the +Makefile. It has the same copyright owner and permissions that configure +itself. diff --git a/configure b/configure new file mode 100755 index 0000000..e2b6a47 --- /dev/null +++ b/configure @@ -0,0 +1,175 @@ +#! /bin/sh +# configure script for Lzd - Educational decompressor for lzip files +# Copyright (C) 2013 Antonio Diaz Diaz. +# +# This configure script is free software: you have unlimited permission +# to copy, distribute and modify it. + +args= +no_create= +pkgname=lzd +pkgversion=0.1 +progname=lzd +srctrigger=decoder.cc + +# clear some things potentially inherited from environment. +LC_ALL=C +export LC_ALL +srcdir= +prefix=/usr/local +exec_prefix='$(prefix)' +bindir='$(exec_prefix)/bin' +datarootdir='$(prefix)/share' +infodir='$(datarootdir)/info' +mandir='$(datarootdir)/man' +CXX=g++ +CPPFLAGS= +CXXFLAGS='-Wall -W -O2' +LDFLAGS= + +# checking whether we are using GNU C++. +if [ ! -x /bin/g++ ] && + [ ! -x /usr/bin/g++ ] && + [ ! -x /usr/local/bin/g++ ] ; then + CXX=c++ + CXXFLAGS='-W -O2' +fi + +# Loop over all args +while [ -n "$1" ] ; do + + # Get the first arg, and shuffle + option=$1 + shift + + # Add the argument quoted to args + args="${args} \"${option}\"" + + # Split out the argument for options that take them + case ${option} in + *=*) optarg=`echo ${option} | sed -e 's,^[^=]*=,,;s,/$,,'` ;; + esac + + # Process the options + case ${option} in + --help | -h) + echo "Usage: configure [options]" + echo + echo "Options: [defaults in brackets]" + echo " -h, --help display this help and exit" + echo " -V, --version output version information and exit" + echo " --srcdir=DIR find the sources in DIR [. or ..]" + echo " --prefix=DIR install into DIR [${prefix}]" + echo " --exec-prefix=DIR base directory for arch-dependent files [${exec_prefix}]" + echo " --bindir=DIR user executables directory [${bindir}]" + echo " --datarootdir=DIR base directory for doc and data [${datarootdir}]" + echo " --infodir=DIR info files directory [${infodir}]" + echo " --mandir=DIR man pages directory [${mandir}]" + echo " CXX=COMPILER C++ compiler to use [g++]" + echo " CPPFLAGS=OPTIONS command line options for the preprocessor [${CPPFLAGS}]" + echo " CXXFLAGS=OPTIONS command line options for the C++ compiler [${CXXFLAGS}]" + echo " LDFLAGS=OPTIONS command line options for the linker [${LDFLAGS}]" + echo + exit 0 ;; + --version | -V) + echo "Configure script for ${pkgname} version ${pkgversion}" + exit 0 ;; + --srcdir=*) srcdir=${optarg} ;; + --prefix=*) prefix=${optarg} ;; + --exec-prefix=*) exec_prefix=${optarg} ;; + --bindir=*) bindir=${optarg} ;; + --datarootdir=*) datarootdir=${optarg} ;; + --infodir=*) infodir=${optarg} ;; + --mandir=*) mandir=${optarg} ;; + --no-create) no_create=yes ;; + + CXX=*) CXX=${optarg} ;; + CPPFLAGS=*) CPPFLAGS=${optarg} ;; + CXXFLAGS=*) CXXFLAGS=${optarg} ;; + LDFLAGS=*) LDFLAGS=${optarg} ;; + + --* | *=* | *-*-*) ;; + *) + echo "configure: Unrecognized option: \"${option}\"; use --help for usage." 1>&2 + exit 1 ;; + esac +done + +# Find the source files, if location was not specified. +srcdirtext= +if [ -z "${srcdir}" ] ; then + srcdirtext="or . or .." ; srcdir=. + if [ ! -r "${srcdir}/${srctrigger}" ] ; then srcdir=.. ; fi + if [ ! -r "${srcdir}/${srctrigger}" ] ; then + ## the sed command below emulates the dirname command + srcdir=`echo $0 | sed -e 's,[^/]*$,,;s,/$,,;s,^$,.,'` + fi +fi + +if [ ! -r "${srcdir}/${srctrigger}" ] ; then + exec 1>&2 + echo + echo "configure: Can't find sources in ${srcdir} ${srcdirtext}" + echo "configure: (At least ${srctrigger} is missing)." + exit 1 +fi + +# Set srcdir to . if that's what it is. +if [ "`pwd`" = "`cd "${srcdir}" ; pwd`" ] ; then srcdir=. ; fi + +echo +if [ -z "${no_create}" ] ; then + echo "creating config.status" + rm -f config.status + cat > config.status << EOF +#! /bin/sh +# This file was generated automatically by configure. Do not edit. +# Run this file to recreate the current configuration. +# +# This script is free software: you have unlimited permission +# to copy, distribute and modify it. + +exec /bin/sh $0 ${args} --no-create +EOF + chmod +x config.status +fi + +echo "creating Makefile" +echo "VPATH = ${srcdir}" +echo "prefix = ${prefix}" +echo "exec_prefix = ${exec_prefix}" +echo "bindir = ${bindir}" +echo "datarootdir = ${datarootdir}" +echo "infodir = ${infodir}" +echo "mandir = ${mandir}" +echo "CXX = ${CXX}" +echo "CPPFLAGS = ${CPPFLAGS}" +echo "CXXFLAGS = ${CXXFLAGS}" +echo "LDFLAGS = ${LDFLAGS}" +rm -f Makefile +cat > Makefile << EOF +# Makefile for Lzd - Educational decompressor for lzip files +# Copyright (C) 2013 Antonio Diaz Diaz. +# This file was generated automatically by configure. Do not edit. +# +# This Makefile is free software: you have unlimited permission +# to copy, distribute and modify it. + +pkgname = ${pkgname} +pkgversion = ${pkgversion} +progname = ${progname} +VPATH = ${srcdir} +prefix = ${prefix} +exec_prefix = ${exec_prefix} +bindir = ${bindir} +datarootdir = ${datarootdir} +infodir = ${infodir} +mandir = ${mandir} +CXX = ${CXX} +CPPFLAGS = ${CPPFLAGS} +CXXFLAGS = ${CXXFLAGS} +LDFLAGS = ${LDFLAGS} +EOF +cat "${srcdir}/Makefile.in" >> Makefile + +echo "OK. Now you can run make." diff --git a/decoder.cc b/decoder.cc new file mode 100644 index 0000000..fbfcdb3 --- /dev/null +++ b/decoder.cc @@ -0,0 +1,363 @@ +/* Lzd - Educational decompressor for lzip files + Copyright (C) 2013 Antonio Diaz Diaz. + + This program is free software: you have unlimited permission + to copy, distribute and modify it. + + 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. +*/ + +class State + { + int st; + +public: + enum { states = 12 }; + State() : st( 0 ) {} + int operator()() const { return st; } + bool is_char() const { return st < 7; } + + void set_char() + { + static const int next[states] = { 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5 }; + st = next[st]; + } + + void set_match() { st = ( ( st < 7 ) ? 7 : 10 ); } + void set_rep() { st = ( ( st < 7 ) ? 8 : 11 ); } + void set_short_rep() { st = ( ( st < 7 ) ? 9 : 11 ); } + }; + + +enum { + literal_context_bits = 3, + pos_state_bits = 2, + pos_states = 1 << pos_state_bits, + pos_state_mask = pos_states - 1, + + max_dis_states = 4, + dis_slot_bits = 6, + start_dis_model = 4, + end_dis_model = 14, + modeled_distances = 1 << (end_dis_model / 2), // 128 + dis_align_bits = 4, + dis_align_size = 1 << dis_align_bits, + + len_low_bits = 3, + len_mid_bits = 3, + len_high_bits = 8, + len_low_symbols = 1 << len_low_bits, + len_mid_symbols = 1 << len_mid_bits, + len_high_symbols = 1 << len_high_bits, + max_len_symbols = len_low_symbols + len_mid_symbols + len_high_symbols, + min_match_len = 2, // must be 2 + + bit_model_move_bits = 5, + bit_model_total_bits = 11, + bit_model_total = 1 << bit_model_total_bits }; + + +struct Bit_model + { + int probability; + Bit_model() : probability( bit_model_total / 2 ) {} + }; + +struct Len_model + { + Bit_model choice1; + Bit_model choice2; + Bit_model bm_low[pos_states][len_low_symbols]; + Bit_model bm_mid[pos_states][len_mid_symbols]; + Bit_model bm_high[len_high_symbols]; + }; + + +class Range_decoder + { + uint32_t code; + uint32_t range; + +public: + Range_decoder() : code( 0 ), range( 0xFFFFFFFFU ) + { + for( int i = 0; i < 5; ++i ) code = (code << 8) | std::getc( stdin ); + } + + int decode( const int num_bits ) + { + int symbol = 0; + for( int i = 0; i < num_bits; ++i ) + { + range >>= 1; + symbol <<= 1; + if( code >= range ) { code -= range; symbol |= 1; } + if( range <= 0x00FFFFFFU ) // normalize + { range <<= 8; code = (code << 8) | std::getc( stdin ); } + } + return symbol; + } + + int decode_bit( Bit_model & bm ) + { + int symbol; + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( code < bound ) + { + range = bound; + bm.probability += (bit_model_total - bm.probability) >> bit_model_move_bits; + symbol = 0; + } + else + { + range -= bound; + code -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + symbol = 1; + } + if( range <= 0x00FFFFFFU ) // normalize + { range <<= 8; code = (code << 8) | std::getc( stdin ); } + return symbol; + } + + int decode_tree( Bit_model bm[], const int num_bits ) + { + int 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 ) + { + int symbol = decode_tree( bm, num_bits ); + int reversed_symbol = 0; + for( int i = 0; i < num_bits; ++i ) + { + reversed_symbol = ( reversed_symbol << 1 ) | ( symbol & 1 ); + symbol >>= 1; + } + return reversed_symbol; + } + + int decode_matched( Bit_model bm[], const int match_byte ) + { + Bit_model * const bm1 = bm + 0x100; + int 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] ); + symbol = ( symbol << 1 ) | bit; + if( match_bit != bit ) + { + while( symbol < 0x100 ) + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + break; + } + } + return symbol - 0x100; + } + + int decode_len( Len_model & lm, const int pos_state ) + { + if( decode_bit( lm.choice1 ) == 0 ) + return min_match_len + + decode_tree( lm.bm_low[pos_state], len_low_bits ); + if( decode_bit( lm.choice2 ) == 0 ) + return min_match_len + len_low_symbols + + decode_tree( lm.bm_mid[pos_state], len_mid_bits ); + return min_match_len + len_low_symbols + len_mid_symbols + + decode_tree( lm.bm_high, len_high_bits ); + } + }; + + +class LZ_decoder + { + unsigned long long partial_data_pos; + Range_decoder rdec; + const unsigned dictionary_size; + uint8_t * const buffer; // output buffer + unsigned pos; // current pos in buffer + unsigned stream_pos; // first byte not yet written to stdout + uint32_t crc_; + + void flush_data(); + + uint8_t get_byte( const unsigned distance ) const + { + int i = pos - distance - 1; + if( i < 0 ) i += dictionary_size; + return buffer[i]; + } + + void put_byte( const uint8_t b ) + { + buffer[pos] = b; + if( ++pos >= dictionary_size ) flush_data(); + } + +public: + LZ_decoder( const unsigned dict_size ) + : + partial_data_pos( 0 ), + dictionary_size( dict_size ), + buffer( new uint8_t[dictionary_size] ), + pos( 0 ), + stream_pos( 0 ), + crc_( 0xFFFFFFFFU ) + { buffer[dictionary_size-1] = 0; } // prev_byte of first_byte + + ~LZ_decoder() { delete[] buffer; } + + unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; } + unsigned long long data_position() const { return partial_data_pos + pos; } + + bool decode_member(); + }; + + +class CRC32 + { + uint32_t data[256]; // Table of CRCs of all 8-bit messages. + +public: + CRC32() + { + for( unsigned n = 0; n < 256; ++n ) + { + unsigned c = n; + for( int k = 0; k < 8; ++k ) + { if( c & 1 ) c = 0xEDB88320U ^ ( c >> 1 ); else c >>= 1; } + data[n] = c; + } + } + + void update( uint32_t & crc, const uint8_t * buffer, const int size ) const + { + for( int i = 0; i < size; ++i ) + crc = data[(crc^buffer[i])&0xFF] ^ ( crc >> 8 ); + } + }; + +const CRC32 crc32; + + +void LZ_decoder::flush_data() + { + if( pos > stream_pos ) + { + const unsigned size = pos - stream_pos; + crc32.update( crc_, buffer + stream_pos, size ); + errno = 0; + if( std::fwrite( buffer + stream_pos, 1, size, stdout ) != size ) + { std::fprintf( stderr, "Write error: %s\n", std::strerror( errno ) ); + std::exit( 1 ); } + if( pos >= dictionary_size ) { partial_data_pos += pos; pos = 0; } + stream_pos = pos; + } + } + + +bool LZ_decoder::decode_member() // Returns false if error + { + Bit_model bm_literal[1<<literal_context_bits][0x300]; + Bit_model bm_match[State::states][pos_states]; + Bit_model bm_rep[State::states]; + Bit_model bm_rep0[State::states]; + Bit_model bm_rep1[State::states]; + Bit_model bm_rep2[State::states]; + Bit_model bm_len[State::states][pos_states]; + Bit_model bm_dis_slot[max_dis_states][1<<dis_slot_bits]; + Bit_model bm_dis[modeled_distances-end_dis_model]; + 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 rep3 = 0; + State state; + + while( !std::feof( stdin ) && !std::ferror( stdin ) ) + { + const int pos_state = data_position() & pos_state_mask; + if( rdec.decode_bit( bm_match[state()][pos_state] ) == 0 ) // 1st bit + { + const uint8_t prev_byte = get_byte( 0 ); + const int literal_state = prev_byte >> ( 8 - literal_context_bits ); + Bit_model * const bm = bm_literal[literal_state]; + if( state.is_char() ) + put_byte( rdec.decode_tree( bm, 8 ) ); + else + put_byte( rdec.decode_matched( bm, get_byte( rep0 ) ) ); + state.set_char(); + } + else + { + int len; + if( rdec.decode_bit( bm_rep[state()] ) == 1 ) // 2nd 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( get_byte( rep0 ) ); continue; } + } + else + { + unsigned distance; + if( rdec.decode_bit( bm_rep1[state()] ) == 0 ) // 4th bit + distance = rep1; + else + { + if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit + distance = rep2; + else + { distance = rep3; rep3 = rep2; } + rep2 = rep1; + } + rep1 = rep0; + rep0 = distance; + } + len = rdec.decode_len( rep_len_model, pos_state ); + state.set_rep(); + } + else + { + rep3 = rep2; rep2 = rep1; rep1 = rep0; + len = rdec.decode_len( match_len_model, pos_state ); + const int dis_state = std::min( len - min_match_len, max_dis_states - 1 ); + const int dis_slot = + rdec.decode_tree( bm_dis_slot[dis_state], dis_slot_bits ); + if( dis_slot < start_dis_model ) rep0 = dis_slot; + else + { + 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, + 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 && !partial_data_pos ) ) + return false; + } + for( int i = 0; i < len; ++i ) + put_byte( get_byte( rep0 ) ); + } + } + return false; + } @@ -0,0 +1,114 @@ +/* Lzd - Educational decompressor for lzip files + Copyright (C) 2013 Antonio Diaz Diaz. + + This program is free software: you have unlimited permission + to copy, distribute and modify it. + + 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. +*/ +/* + Return values: 0 for a normal exit, 1 for environmental problems + (file not found, invalid flags, I/O errors, etc), 2 to indicate a + corrupt or invalid input file. +*/ + +#include <algorithm> +#include <cerrno> +#include <cstdio> +#include <cstdlib> +#include <cstring> +#include <stdint.h> +#include <unistd.h> +#if defined(__MSVCRT__) || defined(__OS2__) +#include <io.h> +#endif + +#include "decoder.cc" + + +enum { min_dictionary_size = 1 << 12, + max_dictionary_size = 1 << 29 }; + +typedef uint8_t File_header[6]; // 0-3 magic, 4 version, 5 coded_dict_size + +typedef uint8_t File_trailer[20]; + // 0-3 CRC32 of the uncompressed data + // 4-11 size of the uncompressed data + // 12-19 member size including header and trailer + + +int main( const int argc, const char * const argv[] ) + { + if( argc > 1 ) + { + std::printf( "Lzd %s - Educational decompressor for lzip files.\n", + PROGVERSION ); + std::printf( "Study the source to learn how a simple lzip decompressor works.\n" + "It is not safe to use it 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) 2013 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" + "Lzip home page: http://www.nongnu.org/lzip/lzip.html\n" ); + return 0; + } + +#if defined(__MSVCRT__) || defined(__OS2__) + setmode( STDIN_FILENO, O_BINARY ); + setmode( STDOUT_FILENO, O_BINARY ); +#endif + + if( isatty( STDIN_FILENO ) ) + { + std::fprintf( stderr, "I won't read compressed data from a terminal.\n" + "Try '%s --help' for more information.\n", argv[0] ); + return 1; + } + + for( bool first_member = true; ; first_member = false ) + { + File_header header; + for( int i = 0; i < 6; ++i ) + header[i] = std::getc( stdin ); + if( std::feof( stdin ) || std::memcmp( header, "LZIP", 4 ) != 0 ) + { + if( first_member ) + { std::fprintf( stderr, "Bad magic number (file not in lzip format)\n" ); + return 2; } + break; + } + if( header[4] != 1 ) + { + std::fprintf( stderr, "Version %d member format not supported.\n", + header[4] ); + return 2; + } + 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::fprintf( stderr, "Invalid dictionary size in member header\n" ); + return 2; } + + LZ_decoder decoder( dict_size ); + if( !decoder.decode_member() ) + { std::fprintf( stderr, "Data error\n" ); return 2; } + + File_trailer 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]; } + unsigned long long data_size = 0; + for( int i = 11; i >= 4; --i ) { data_size <<= 8; data_size += trailer[i]; } + if( crc != decoder.crc() || data_size != decoder.data_position() ) + { std::fprintf( stderr, "CRC error\n" ); return 2; } + } + + if( std::fclose( stdout ) != 0 ) + { std::fprintf( stderr, "Can't close stdout: %s\n", std::strerror( errno ) ); + return 1; } + return 0; + } diff --git a/testsuite/check.sh b/testsuite/check.sh new file mode 100755 index 0000000..6dd7bb8 --- /dev/null +++ b/testsuite/check.sh @@ -0,0 +1,43 @@ +#! /bin/sh +# check script for Lzd - Educational decompressor for lzip files +# Copyright (C) 2013 Antonio Diaz Diaz. +# +# This script is free software: you have unlimited permission +# to copy, distribute and modify it. + +LC_ALL=C +export LC_ALL +objdir=`pwd` +testdir=`cd "$1" ; pwd` +LZIP="${objdir}"/lzd +framework_failure() { echo "failure in testing framework" ; exit 1 ; } + +if [ ! -x "${LZIP}" ] ; then + echo "${LZIP}: cannot execute" + exit 1 +fi + +if [ -d tmp ] ; then rm -rf tmp ; fi +mkdir tmp +cd "${objdir}"/tmp + +in="${testdir}"/test.txt +in_lz="${testdir}"/test.txt.lz +fail=0 + +printf "testing lzd-%s..." "$2" + +"${LZIP}" < "${in_lz}" | cmp "${in}" - || fail=1 +printf . +cat "${in_lz}" "${in_lz}" | "${LZIP}" > copy2 || fail=1 +cat "${in}" "${in}" | cmp copy2 - || fail=1 +printf . + +echo +if [ ${fail} = 0 ] ; then + echo "tests completed successfully." + cd "${objdir}" && rm -r tmp +else + echo "tests failed." +fi +exit ${fail} diff --git a/testsuite/test.txt b/testsuite/test.txt new file mode 100644 index 0000000..5b244d5 --- /dev/null +++ b/testsuite/test.txt @@ -0,0 +1,676 @@ +
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users. We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors. You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+ To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights. Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received. You must make sure that they, too, receive
+or can get the source code. And you must show them these terms so they
+know their rights.
+
+ Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+ For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software. For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+ Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so. This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software. The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable. Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products. If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+ Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary. To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ TERMS AND CONDITIONS
+
+ 0. Definitions.
+
+ "This License" refers to version 3 of the GNU General Public License.
+
+ "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+ "The Program" refers to any copyrightable work licensed under this
+License. Each licensee is addressed as "you". "Licensees" and
+"recipients" may be individuals or organizations.
+
+ To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy. The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+ A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+ To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy. Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+ To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies. Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+ An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License. If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+ 1. Source Code.
+
+ The "source code" for a work means the preferred form of the work
+for making modifications to it. "Object code" means any non-source
+form of a work.
+
+ A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+ The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form. A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+ The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities. However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work. For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+ The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+ The Corresponding Source for a work in source code form is that
+same work.
+
+ 2. Basic Permissions.
+
+ All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met. This License explicitly affirms your unlimited
+permission to run the unmodified Program. The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work. This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+ You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force. You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright. Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+ Conveying under any other circumstances is permitted solely under
+the conditions stated below. Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+ 3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+ No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+ When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+ 4. Conveying Verbatim Copies.
+
+ You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+ You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+ 5. Conveying Modified Source Versions.
+
+ You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+ a) The work must carry prominent notices stating that you modified
+ it, and giving a relevant date.
+
+ b) The work must carry prominent notices stating that it is
+ released under this License and any conditions added under section
+ 7. This requirement modifies the requirement in section 4 to
+ "keep intact all notices".
+
+ c) You must license the entire work, as a whole, under this
+ License to anyone who comes into possession of a copy. This
+ License will therefore apply, along with any applicable section 7
+ additional terms, to the whole of the work, and all its parts,
+ regardless of how they are packaged. This License gives no
+ permission to license the work in any other way, but it does not
+ invalidate such permission if you have separately received it.
+
+ d) If the work has interactive user interfaces, each must display
+ Appropriate Legal Notices; however, if the Program has interactive
+ interfaces that do not display Appropriate Legal Notices, your
+ work need not make them do so.
+
+ A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit. Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+ 6. Conveying Non-Source Forms.
+
+ You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+ a) Convey the object code in, or embodied in, a physical product
+ (including a physical distribution medium), accompanied by the
+ Corresponding Source fixed on a durable physical medium
+ customarily used for software interchange.
+
+ b) Convey the object code in, or embodied in, a physical product
+ (including a physical distribution medium), accompanied by a
+ written offer, valid for at least three years and valid for as
+ long as you offer spare parts or customer support for that product
+ model, to give anyone who possesses the object code either (1) a
+ copy of the Corresponding Source for all the software in the
+ product that is covered by this License, on a durable physical
+ medium customarily used for software interchange, for a price no
+ more than your reasonable cost of physically performing this
+ conveying of source, or (2) access to copy the
+ Corresponding Source from a network server at no charge.
+
+ c) Convey individual copies of the object code with a copy of the
+ written offer to provide the Corresponding Source. This
+ alternative is allowed only occasionally and noncommercially, and
+ only if you received the object code with such an offer, in accord
+ with subsection 6b.
+
+ d) Convey the object code by offering access from a designated
+ place (gratis or for a charge), and offer equivalent access to the
+ Corresponding Source in the same way through the same place at no
+ further charge. You need not require recipients to copy the
+ Corresponding Source along with the object code. If the place to
+ copy the object code is a network server, the Corresponding Source
+ may be on a different server (operated by you or a third party)
+ that supports equivalent copying facilities, provided you maintain
+ clear directions next to the object code saying where to find the
+ Corresponding Source. Regardless of what server hosts the
+ Corresponding Source, you remain obligated to ensure that it is
+ available for as long as needed to satisfy these requirements.
+
+ e) Convey the object code using peer-to-peer transmission, provided
+ you inform other peers where the object code and Corresponding
+ Source of the work are being offered to the general public at no
+ charge under subsection 6d.
+
+ A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+ A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling. In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage. For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product. A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+ "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source. The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+ If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information. But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+ The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed. Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+ Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+ 7. Additional Terms.
+
+ "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law. If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+ When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it. (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.) You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+ Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+ a) Disclaiming warranty or limiting liability differently from the
+ terms of sections 15 and 16 of this License; or
+
+ b) Requiring preservation of specified reasonable legal notices or
+ author attributions in that material or in the Appropriate Legal
+ Notices displayed by works containing it; or
+
+ c) Prohibiting misrepresentation of the origin of that material, or
+ requiring that modified versions of such material be marked in
+ reasonable ways as different from the original version; or
+
+ d) Limiting the use for publicity purposes of names of licensors or
+ authors of the material; or
+
+ e) Declining to grant rights under trademark law for use of some
+ trade names, trademarks, or service marks; or
+
+ f) Requiring indemnification of licensors and authors of that
+ material by anyone who conveys the material (or modified versions of
+ it) with contractual assumptions of liability to the recipient, for
+ any liability that these contractual assumptions directly impose on
+ those licensors and authors.
+
+ All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10. If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term. If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+ If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+ Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+ 8. Termination.
+
+ You may not propagate or modify a covered work except as expressly
+provided under this License. Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+ However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+ Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+ Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License. If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+ 9. Acceptance Not Required for Having Copies.
+
+ You are not required to accept this License in order to receive or
+run a copy of the Program. Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance. However,
+nothing other than this License grants you permission to propagate or
+modify any covered work. These actions infringe copyright if you do
+not accept this License. Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+ 10. Automatic Licensing of Downstream Recipients.
+
+ Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License. You are not responsible
+for enforcing compliance by third parties with this License.
+
+ An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations. If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+ You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License. For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+ 11. Patents.
+
+ A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based. The
+work thus licensed is called the contributor's "contributor version".
+
+ A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version. For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+ Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+ In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement). To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+ If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients. "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+ If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+ A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License. You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+ Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all. For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+ 13. Use with the GNU Affero General Public License.
+
+ Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work. The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+ 14. Revised Versions of this License.
+
+ The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ 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 3 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.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ <program> Copyright (C) <year> <name of author>
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.
+
diff --git a/testsuite/test.txt.lz b/testsuite/test.txt.lz Binary files differnew file mode 100644 index 0000000..4db881a --- /dev/null +++ b/testsuite/test.txt.lz |