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-rw-r--r--AUTHORS6
-rw-r--r--COPYING17
-rw-r--r--ChangeLog82
-rw-r--r--INSTALL58
-rw-r--r--Makefile.in122
-rw-r--r--NEWS4
-rw-r--r--README37
-rwxr-xr-xconfigure198
-rw-r--r--lzd.cc488
-rwxr-xr-xtestsuite/check.sh104
-rw-r--r--testsuite/fox.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_bcrc.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_bm.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_crc0.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_das46.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_de20.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_mes81.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_s11.lzbin0 -> 80 bytes
-rw-r--r--testsuite/fox_v2.lzbin0 -> 80 bytes
-rw-r--r--testsuite/test.txt676
-rw-r--r--testsuite/test.txt.lzbin0 -> 7376 bytes
-rw-r--r--testsuite/test_em.txt.lzbin0 -> 14024 bytes
22 files changed, 1792 insertions, 0 deletions
diff --git a/AUTHORS b/AUTHORS
new file mode 100644
index 0000000..48f7099
--- /dev/null
+++ b/AUTHORS
@@ -0,0 +1,6 @@
+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), Andrei 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/COPYING b/COPYING
new file mode 100644
index 0000000..0105f19
--- /dev/null
+++ b/COPYING
@@ -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.
diff --git a/ChangeLog b/ChangeLog
new file mode 100644
index 0000000..f417214
--- /dev/null
+++ b/ChangeLog
@@ -0,0 +1,82 @@
+2024-01-02 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 1.4 released.
+ * lzd.cc: Use header_size and trailer_size instead of 6 and 20.
+
+2022-10-24 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 1.3 released.
+ * lzd.cc (Range_decoder): Discard first byte explicitly.
+
+2021-01-04 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 1.2 released.
+ * lzd.cc (main): Check also mismatches in member size.
+ Accept and ignore the option '-d' for compatibility with zutils.
+ Remove warning about "lzd not safe for real work".
+ Print license notice.
+ * testsuite: Add 10 new test files.
+
+2019-01-11 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 1.1 released.
+ * Rename File_* to Lzip_*.
+ * lzd.cc: Compile on DOS with DJGPP.
+ * configure: Accept appending to CXXFLAGS; 'CXXFLAGS+=OPTIONS'.
+
+2017-05-02 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 1.0 released.
+ * lzd.cc: Minor code improvements.
+ * check.sh: A POSIX shell is required to run the tests.
+
+2016-05-10 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.9 released.
+ * configure: Avoid warning on some shells when testing for g++.
+
+2016-01-23 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.8 released.
+ * Document that lzip does not use 'literal_pos_state_bits'.
+
+2015-07-07 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.7 released.
+ * Minor changes.
+
+2014-08-25 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.6 released.
+ * Minor changes.
+
+2013-09-17 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.5 released.
+ * Minor changes.
+
+2013-08-01 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.4 released.
+ * check.sh: Remove '/dev/full' from tests.
+
+2013-07-24 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.3 released.
+ * decoder.cc and main.cc have been merged into lzd.cc.
+
+2013-05-06 Antonio Diaz Diaz <antonio@gnu.org>
+
+ * Version 0.2 released.
+ * main.c: Add a missing '#include' for OS/2.
+
+2013-03-21 Antonio Diaz Diaz <ant_diaz@teleline.es>
+
+ * Version 0.1 released.
+
+
+Copyright (C) 2013-2024 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.
diff --git a/INSTALL b/INSTALL
new file mode 100644
index 0000000..2c82368
--- /dev/null
+++ b/INSTALL
@@ -0,0 +1,58 @@
+Requirements
+------------
+You will need a C++98 compiler with support for 'long long'.
+(gcc 3.3.6 or newer is recommended).
+I use gcc 6.1.0 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:
+
+ tar -xf lzd[version].tar.lz
+or
+ lzip -cd lzd[version].tar.lz | tar -xf -
+
+This creates the directory ./lzd[version] containing the source code
+extracted from the archive.
+
+2. Change to lzd directory and run configure.
+ (Try 'configure --help' for usage instructions).
+
+ cd lzd[version]
+ ./configure
+
+3. Run make.
+
+ make
+
+4. Optionally, type 'make check' to run the tests that come with lzd.
+
+5. Type 'make install' to install the program and any data files and
+ documentation. You need root privileges to install into a prefix owned
+ by root.
+
+
+Another way
+-----------
+You can also compile lzd into a separate directory.
+To do this, you must use a version of 'make' that supports the variable
+'VPATH', 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 source code. Usually 'configure' can determine that directory
+automatically.
+
+After running 'configure', you can run 'make' and 'make install' as
+explained above.
+
+
+Copyright (C) 2013-2024 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..120a41b
--- /dev/null
+++ b/Makefile.in
@@ -0,0 +1,122 @@
+
+DISTNAME = $(pkgname)-$(pkgversion)
+INSTALL = install
+INSTALL_PROGRAM = $(INSTALL) -m 755
+INSTALL_DATA = $(INSTALL) -m 644
+INSTALL_DIR = $(INSTALL) -d -m 755
+SHELL = /bin/sh
+CAN_RUN_INSTALLINFO = $(SHELL) -c "install-info --version" > /dev/null 2>&1
+
+objs = lzd.o
+
+
+.PHONY : all install install-bin install-info install-man \
+ install-strip install-compress install-strip-compress \
+ install-bin-strip install-info-compress install-man-compress \
+ uninstall uninstall-bin uninstall-info uninstall-man \
+ doc info man check dist clean distclean
+
+all : $(progname)
+
+$(progname) : $(objs)
+ $(CXX) $(CXXFLAGS) $(LDFLAGS) -o $@ $(objs)
+
+%.o : %.cc
+ $(CXX) $(CPPFLAGS) $(CXXFLAGS) -DPROGVERSION=\"$(pkgversion)\" -c -o $@ $<
+
+# prevent 'make' from trying to remake source files
+$(VPATH)/configure $(VPATH)/Makefile.in $(VPATH)/doc/$(pkgname).texi : ;
+%.h %.cc : ;
+
+$(objs) : Makefile
+
+doc :
+
+info : $(VPATH)/doc/$(pkgname).info
+
+$(VPATH)/doc/$(pkgname).info : $(VPATH)/doc/$(pkgname).texi
+ cd $(VPATH)/doc && $(MAKEINFO) $(pkgname).texi
+
+man : $(VPATH)/doc/$(progname).1
+
+$(VPATH)/doc/$(progname).1 : $(progname)
+ help2man -n 'educational decompressor for the lzip format' \
+ -o $@ --no-info ./$(progname)
+
+Makefile : $(VPATH)/configure $(VPATH)/Makefile.in
+ ./config.status
+
+check : all
+ @$(VPATH)/testsuite/check.sh $(VPATH)/testsuite $(pkgversion)
+
+install : install-bin
+install-strip : install-bin-strip
+install-compress : install-bin
+install-strip-compress : install-bin-strip
+
+install-bin : all
+ if [ ! -d "$(DESTDIR)$(bindir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(bindir)" ; fi
+ $(INSTALL_PROGRAM) ./$(progname) "$(DESTDIR)$(bindir)/$(progname)"
+
+install-bin-strip : all
+ $(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' install-bin
+
+install-info :
+ if [ ! -d "$(DESTDIR)$(infodir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(infodir)" ; fi
+ -rm -f "$(DESTDIR)$(infodir)/$(pkgname).info"*
+ $(INSTALL_DATA) $(VPATH)/doc/$(pkgname).info "$(DESTDIR)$(infodir)/$(pkgname).info"
+ -if $(CAN_RUN_INSTALLINFO) ; then \
+ install-info --info-dir="$(DESTDIR)$(infodir)" "$(DESTDIR)$(infodir)/$(pkgname).info" ; \
+ fi
+
+install-info-compress : install-info
+ lzip -v -9 "$(DESTDIR)$(infodir)/$(pkgname).info"
+
+install-man :
+ if [ ! -d "$(DESTDIR)$(mandir)/man1" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1" ; fi
+ -rm -f "$(DESTDIR)$(mandir)/man1/$(progname).1"*
+ $(INSTALL_DATA) $(VPATH)/doc/$(progname).1 "$(DESTDIR)$(mandir)/man1/$(progname).1"
+
+install-man-compress : install-man
+ lzip -v -9 "$(DESTDIR)$(mandir)/man1/$(progname).1"
+
+uninstall : uninstall-bin
+
+uninstall-bin :
+ -rm -f "$(DESTDIR)$(bindir)/$(progname)"
+
+uninstall-info :
+ -if $(CAN_RUN_INSTALLINFO) ; then \
+ install-info --info-dir="$(DESTDIR)$(infodir)" --remove "$(DESTDIR)$(infodir)/$(pkgname).info" ; \
+ fi
+ -rm -f "$(DESTDIR)$(infodir)/$(pkgname).info"*
+
+uninstall-man :
+ -rm -f "$(DESTDIR)$(mandir)/man1/$(progname).1"*
+
+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/fox.lz \
+ $(DISTNAME)/testsuite/fox_*.lz \
+ $(DISTNAME)/testsuite/test.txt.lz \
+ $(DISTNAME)/testsuite/test_em.txt.lz
+ rm -f $(DISTNAME)
+ lzip -v -9 $(DISTNAME).tar
+
+clean :
+ -rm -f $(progname) $(objs)
+
+distclean : clean
+ -rm -f Makefile config.status *.tar *.tar.lz
diff --git a/NEWS b/NEWS
new file mode 100644
index 0000000..be2c30b
--- /dev/null
+++ b/NEWS
@@ -0,0 +1,4 @@
+Changes in version 1.4:
+
+Define constants 'header_size' and 'trailer_size' instead of using 6 and 20.
+(Lzd is supposed to be educational, and using numbers is bad practice).
diff --git a/README b/README
new file mode 100644
index 0000000..03fb742
--- /dev/null
+++ b/README
@@ -0,0 +1,37 @@
+Description
+
+Lzd is a simplified decompressor for the lzip format with an educational
+purpose. Studying its source code is a good first step to understand how
+lzip works. Lzd is written in C++.
+
+The source code of lzd is used in the lzip manual as a reference
+decompressor in the description of the lzip file format. Reading the lzip
+manual will help you understand the source code. Lzd is compliant with the
+lzip specification; it checks the 3 integrity factors.
+
+The source code of lzd is also used as a reference in the description of the
+media type 'application/lzip'.
+See http://datatracker.ietf.org/doc/draft-diaz-lzip
+
+Lzd decompresses from standard input to standard output. It accepts (and
+ignores) the option '-d' for compatibility with other lzip tools. In
+particular, accepting the option '-d' allows lzd to be used as argument to
+the option '--lz' of the tools from the zutils package.
+
+Lzd correctly decompresses 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 checked.
+
+The ideas embodied in lzd are due to (at least) the following people:
+Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei 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) 2013-2024 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..a84fda2
--- /dev/null
+++ b/configure
@@ -0,0 +1,198 @@
+#! /bin/sh
+# configure script for Lzd - Educational decompressor for the lzip format
+# Copyright (C) 2013-2024 Antonio Diaz Diaz.
+#
+# This configure script is free software: you have unlimited permission
+# to copy, distribute, and modify it.
+
+pkgname=lzd
+pkgversion=1.4
+progname=lzd
+srctrigger=lzd.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=
+MAKEINFO=makeinfo
+
+# checking whether we are using GNU C++.
+/bin/sh -c "${CXX} --version" > /dev/null 2>&1 || { CXX=c++ ; CXXFLAGS=-O2 ; }
+
+# Loop over all args
+args=
+no_create=
+while [ $# != 0 ] ; do
+
+ # Get the first arg, and shuffle
+ option=$1 ; arg2=no
+ shift
+
+ # Add the argument quoted to args
+ if [ -z "${args}" ] ; then args="\"${option}\""
+ else args="${args} \"${option}\"" ; fi
+
+ # 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: $0 [OPTION]... [VAR=VALUE]..."
+ echo
+ echo "To assign makefile variables (e.g., CXX, CXXFLAGS...), specify them as"
+ echo "arguments to configure in the form VAR=VALUE."
+ echo
+ echo "Options and variables: [defaults in brackets]"
+ echo " -h, --help display this help and exit"
+ echo " -V, --version output version information and exit"
+ echo " --srcdir=DIR find the source code in DIR [. or ..]"
+ echo " --prefix=DIR install into DIR [${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 [${mandir}]"
+ echo " CXX=COMPILER C++ compiler to use [${CXX}]"
+ echo " CPPFLAGS=OPTIONS command-line options for the preprocessor [${CPPFLAGS}]"
+ echo " CXXFLAGS=OPTIONS command-line options for the C++ compiler [${CXXFLAGS}]"
+ echo " CXXFLAGS+=OPTIONS append options to the current value of CXXFLAGS"
+ echo " LDFLAGS=OPTIONS command-line options for the linker [${LDFLAGS}]"
+ echo " MAKEINFO=NAME makeinfo program to use [${MAKEINFO}]"
+ echo
+ exit 0 ;;
+ --version | -V)
+ echo "Configure script for ${pkgname} version ${pkgversion}"
+ exit 0 ;;
+ --srcdir) srcdir=$1 ; arg2=yes ;;
+ --prefix) prefix=$1 ; arg2=yes ;;
+ --exec-prefix) exec_prefix=$1 ; arg2=yes ;;
+ --bindir) bindir=$1 ; arg2=yes ;;
+ --datarootdir) datarootdir=$1 ; arg2=yes ;;
+ --infodir) infodir=$1 ; arg2=yes ;;
+ --mandir) mandir=$1 ; arg2=yes ;;
+
+ --srcdir=*) srcdir=${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=${optarg} ;;
+ CXXFLAGS+=*) CXXFLAGS="${CXXFLAGS} ${optarg}" ;;
+ LDFLAGS=*) LDFLAGS=${optarg} ;;
+ MAKEINFO=*) MAKEINFO=${optarg} ;;
+
+ --*)
+ echo "configure: WARNING: unrecognized option: '${option}'" 1>&2 ;;
+ *=* | *-*-*) ;;
+ *)
+ echo "configure: unrecognized option: '${option}'" 1>&2
+ echo "Try 'configure --help' for more information." 1>&2
+ exit 1 ;;
+ esac
+
+ # Check if the option took a separate argument
+ if [ "${arg2}" = yes ] ; then
+ if [ $# != 0 ] ; then args="${args} \"$1\"" ; shift
+ else echo "configure: Missing argument to '${option}'" 1>&2
+ exit 1
+ fi
+ fi
+done
+
+# Find the source code, 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
+ echo "configure: Can't find source code in ${srcdir} ${srcdirtext}" 1>&2
+ echo "configure: (At least ${srctrigger} is missing)." 1>&2
+ exit 1
+fi
+
+# Set srcdir to . if that's what it is.
+if [ "`pwd`" = "`cd "${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. Don't 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}"
+echo "MAKEINFO = ${MAKEINFO}"
+rm -f Makefile
+cat > Makefile << EOF
+# Makefile for Lzd - Educational decompressor for the lzip format
+# Copyright (C) 2013-2024 Antonio Diaz Diaz.
+# This file was generated automatically by configure. Don't 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}
+MAKEINFO = ${MAKEINFO}
+EOF
+cat "${srcdir}/Makefile.in" >> Makefile
+
+echo "OK. Now you can run make."
diff --git a/lzd.cc b/lzd.cc
new file mode 100644
index 0000000..3cf3f13
--- /dev/null
+++ b/lzd.cc
@@ -0,0 +1,488 @@
+/* Lzd - Educational decompressor for the lzip format
+ 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
+ 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.
+*/
+/*
+ Exit status: 0 for a normal exit, 1 for environmental problems
+ (file not found, invalid command-line options, 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__ || defined __DJGPP__
+#include <fcntl.h>
+#include <io.h>
+#endif
+
+
+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()
+ {
+ 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 {
+ min_dictionary_size = 1 << 12,
+ max_dictionary_size = 1 << 29,
+ literal_context_bits = 3,
+ literal_pos_state_bits = 0, // not used
+ pos_state_bits = 2,
+ pos_states = 1 << pos_state_bits,
+ pos_state_mask = pos_states - 1,
+
+ len_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 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_buf( uint32_t & crc, const uint8_t * const buffer,
+ const int size ) const
+ {
+ for( int i = 0; i < size; ++i )
+ crc = data[(crc^buffer[i])&0xFF] ^ ( crc >> 8 );
+ }
+ };
+
+const CRC32 crc32;
+
+
+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
+
+class Range_decoder
+ {
+ unsigned long long member_pos;
+ uint32_t code;
+ uint32_t range;
+
+public:
+ 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();
+ }
+
+ uint8_t get_byte() { ++member_pos; return std::getc( stdin ); }
+ unsigned long long member_position() const { return member_pos; }
+
+ unsigned decode( const int num_bits )
+ {
+ unsigned symbol = 0;
+ for( int i = num_bits; i > 0; --i )
+ {
+ range >>= 1;
+ symbol <<= 1;
+ if( code >= range ) { code -= range; symbol |= 1; }
+ if( range <= 0x00FFFFFFU ) // normalize
+ { range <<= 8; code = ( code << 8 ) | get_byte(); }
+ }
+ return symbol;
+ }
+
+ bool decode_bit( Bit_model & bm )
+ {
+ bool 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
+ {
+ code -= bound;
+ range -= bound;
+ bm.probability -= bm.probability >> bit_model_move_bits;
+ symbol = 1;
+ }
+ if( range <= 0x00FFFFFFU ) // normalize
+ { range <<= 8; code = ( code << 8 ) | get_byte(); }
+ return symbol;
+ }
+
+ unsigned decode_tree( Bit_model bm[], const int num_bits )
+ {
+ unsigned symbol = 1;
+ for( int i = 0; i < num_bits; ++i )
+ symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+ return symbol - ( 1 << num_bits );
+ }
+
+ unsigned decode_tree_reversed( Bit_model bm[], const int num_bits )
+ {
+ 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 );
+ symbol >>= 1;
+ }
+ return reversed_symbol;
+ }
+
+ unsigned decode_matched( Bit_model bm[], const unsigned match_byte )
+ {
+ unsigned symbol = 1;
+ for( int i = 7; i >= 0; --i )
+ {
+ 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 )
+ {
+ while( symbol < 0x100 )
+ symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+ break;
+ }
+ }
+ return symbol & 0xFF;
+ }
+
+ unsigned 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_;
+ bool pos_wrapped;
+
+ void flush_data();
+
+ uint8_t peek( const unsigned distance ) const
+ {
+ 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 )
+ {
+ buffer[pos] = b;
+ if( ++pos >= dictionary_size ) flush_data();
+ }
+
+public:
+ explicit 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 ),
+ pos_wrapped( false )
+ {}
+
+ ~LZ_decoder() { delete[] buffer; }
+
+ unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; }
+ unsigned long long data_position() const
+ { return partial_data_pos + pos; }
+ uint8_t get_byte() { return rdec.get_byte(); }
+ unsigned long long member_position() const
+ { return rdec.member_position(); }
+
+ bool decode_member();
+ };
+
+
+void LZ_decoder::flush_data()
+ {
+ if( pos > stream_pos )
+ {
+ const unsigned size = pos - stream_pos;
+ crc32.update_buf( crc_, buffer + stream_pos, size );
+ 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; pos_wrapped = true; }
+ stream_pos = pos;
+ }
+ }
+
+
+bool LZ_decoder::decode_member() // Return 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[len_states][1<<dis_slot_bits];
+ 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 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
+ {
+ // 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];
+ if( state.is_char() )
+ put_byte( rdec.decode_tree( bm, 8 ) );
+ else
+ put_byte( rdec.decode_matched( bm, peek( rep0 ) ) );
+ state.set_char();
+ continue;
+ }
+ // match or repeated match
+ 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_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
+ {
+ if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit
+ distance = rep2;
+ else
+ { distance = rep3; rep3 = rep2; }
+ rep2 = rep1;
+ }
+ rep1 = rep0;
+ rep0 = distance;
+ }
+ state.set_rep();
+ len = rdec.decode_len( rep_len_model, pos_state );
+ }
+ else // match
+ {
+ rep3 = rep2; rep2 = rep1; rep1 = rep0;
+ 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;
+ }
+
+
+int main( const int argc, const char * const argv[] )
+ {
+ if( argc > 2 || ( argc == 2 && std::strcmp( argv[1], "-d" ) != 0 ) )
+ {
+ std::printf(
+ "Lzd %s - Educational decompressor for the lzip format.\n"
+ "Study the source code to learn how a lzip decompressor works.\n"
+ "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) 2024 Antonio Diaz Diaz.\n"
+ "License 2-clause BSD.\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] );
+ return 0;
+ }
+
+#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 )
+ {
+ 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 )
+ { std::fputs( "Bad magic number (file not in lzip format).\n",
+ stderr ); return 2; }
+ break; // ignore trailing data
+ }
+ 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; }
+
+ LZ_decoder decoder( dict_size ); // decode LZMA stream
+ if( !decoder.decode_member() )
+ { std::fputs( "Data error\n", stderr ); return 2; }
+
+ 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];
+ if( crc != decoder.crc() )
+ { std::fputs( "CRC mismatch\n", stderr ); retval = 2; }
+
+ unsigned long long data_size = 0;
+ for( int i = 11; i >= 4; --i )
+ data_size = ( data_size << 8 ) + trailer[i];
+ if( data_size != decoder.data_position() )
+ { std::fputs( "Data size mismatch\n", stderr ); retval = 2; }
+
+ unsigned long long member_size = 0;
+ for( int i = 19; i >= 12; --i )
+ member_size = ( member_size << 8 ) + trailer[i];
+ if( member_size != decoder.member_position() )
+ { std::fputs( "Member size mismatch\n", stderr ); retval = 2; }
+ if( retval ) return retval;
+ }
+
+ if( std::fclose( stdout ) != 0 )
+ { std::fprintf( stderr, "Error closing 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..b041fe8
--- /dev/null
+++ b/testsuite/check.sh
@@ -0,0 +1,104 @@
+#! /bin/sh
+# check script for Lzd - Educational decompressor for the lzip format
+# Copyright (C) 2013-2024 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 [ ! -f "${LZIP}" ] || [ ! -x "${LZIP}" ] ; then
+ echo "${LZIP}: cannot execute"
+ exit 1
+fi
+
+[ -e "${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
+
+in="${testdir}"/test.txt
+in_lz="${testdir}"/test.txt.lz
+in_em="${testdir}"/test_em.txt.lz
+fox_lz="${testdir}"/fox.lz
+fail=0
+test_failed() { fail=1 ; printf " $1" ; [ -z "$2" ] || printf "($2)" ; }
+
+printf "testing lzd-%s..." "$2"
+
+"${LZIP}" < "${in}" 2> /dev/null
+[ $? = 2 ] || test_failed $LINENO
+
+for i in "${in_lz}" "${in_em}" ; do
+ "${LZIP}" < "$i" > out || test_failed $LINENO "$i"
+ cmp "${in}" out || test_failed $LINENO "$i"
+done
+
+cat "${in}" "${in}" > in2 || framework_failure
+cat "${in_lz}" "${in_lz}" | "${LZIP}" > out2 || test_failed $LINENO
+cmp in2 out2 || test_failed $LINENO
+rm -f out2 || framework_failure
+
+cat "${in_lz}" "${in_lz}" > out2.lz || framework_failure
+printf "\ngarbage" >> out2.lz || framework_failure
+"${LZIP}" -d < out2.lz > out2 || test_failed $LINENO
+cmp in2 out2 || test_failed $LINENO
+rm -f in2 out2 out2.lz || framework_failure
+
+printf "\ntesting bad input..."
+
+for i in fox_bm.lz fox_v2.lz fox_s11.lz fox_de20.lz \
+ fox_bcrc.lz fox_crc0.lz fox_das46.lz fox_mes81.lz ; do
+ "${LZIP}" < "${testdir}"/$i > /dev/null 2>&1
+ [ $? = 2 ] || test_failed $LINENO $i
+done
+
+"${LZIP}" < "${fox_lz}" > fox || test_failed $LINENO
+for i in fox_bcrc.lz fox_crc0.lz fox_das46.lz fox_mes81.lz ; do
+ "${LZIP}" < "${testdir}"/$i > out 2> /dev/null
+ [ $? = 2 ] || test_failed $LINENO $i
+ cmp fox out || test_failed $LINENO $i
+done
+rm -f fox out || framework_failure
+
+cat "${in_lz}" "${in_lz}" > in2.lz || framework_failure
+cat "${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 > /dev/null 2>&1
+ [ $? = 2 ] || test_failed $LINENO $i
+ done
+else
+ printf "\nwarning: skipping truncation test: 'dd' does not work on your system."
+fi
+rm -f in2.lz in3.lz trunc.lz || framework_failure
+
+cat "${in_lz}" > ingin.lz || framework_failure
+printf "g" >> ingin.lz || framework_failure
+cat "${in_lz}" >> ingin.lz || framework_failure
+"${LZIP}" -d < ingin.lz > out || test_failed $LINENO
+cmp "${in}" out || test_failed $LINENO
+rm -f out ingin.lz || framework_failure
+
+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/fox.lz b/testsuite/fox.lz
new file mode 100644
index 0000000..509da82
--- /dev/null
+++ b/testsuite/fox.lz
Binary files differ
diff --git a/testsuite/fox_bcrc.lz b/testsuite/fox_bcrc.lz
new file mode 100644
index 0000000..8f6a7c4
--- /dev/null
+++ b/testsuite/fox_bcrc.lz
Binary files differ
diff --git a/testsuite/fox_bm.lz b/testsuite/fox_bm.lz
new file mode 100644
index 0000000..d71914f
--- /dev/null
+++ b/testsuite/fox_bm.lz
Binary files differ
diff --git a/testsuite/fox_crc0.lz b/testsuite/fox_crc0.lz
new file mode 100644
index 0000000..1abe926
--- /dev/null
+++ b/testsuite/fox_crc0.lz
Binary files differ
diff --git a/testsuite/fox_das46.lz b/testsuite/fox_das46.lz
new file mode 100644
index 0000000..43ed9f9
--- /dev/null
+++ b/testsuite/fox_das46.lz
Binary files differ
diff --git a/testsuite/fox_de20.lz b/testsuite/fox_de20.lz
new file mode 100644
index 0000000..10949d8
--- /dev/null
+++ b/testsuite/fox_de20.lz
Binary files differ
diff --git a/testsuite/fox_mes81.lz b/testsuite/fox_mes81.lz
new file mode 100644
index 0000000..d50ef2e
--- /dev/null
+++ b/testsuite/fox_mes81.lz
Binary files differ
diff --git a/testsuite/fox_s11.lz b/testsuite/fox_s11.lz
new file mode 100644
index 0000000..dca909c
--- /dev/null
+++ b/testsuite/fox_s11.lz
Binary files differ
diff --git a/testsuite/fox_v2.lz b/testsuite/fox_v2.lz
new file mode 100644
index 0000000..8620981
--- /dev/null
+++ b/testsuite/fox_v2.lz
Binary files differ
diff --git a/testsuite/test.txt b/testsuite/test.txt
new file mode 100644
index 0000000..9196a3a
--- /dev/null
+++ b/testsuite/test.txt
@@ -0,0 +1,676 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.) 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
+this service 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 make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. 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.
+
+ We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+ Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+ Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ GNU GENERAL PUBLIC LICENSE
+ TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+ 0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License. The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language. (Hereinafter, translation is included without limitation in
+the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+ 1. You may copy and distribute 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 and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+ 2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+ a) You must cause the modified files to carry prominent notices
+ stating that you changed the files and the date of any change.
+
+ b) You must cause any work that you distribute or publish, that in
+ whole or in part contains or is derived from the Program or any
+ part thereof, to be licensed as a whole at no charge to all third
+ parties under the terms of this License.
+
+ c) If the modified program normally reads commands interactively
+ when run, you must cause it, when started running for such
+ interactive use in the most ordinary way, to print or display an
+ announcement including an appropriate copyright notice and a
+ notice that there is no warranty (or else, saying that you provide
+ a warranty) and that users may redistribute the program under
+ these conditions, and telling the user how to view a copy of this
+ License. (Exception: if the Program itself is interactive but
+ does not normally print such an announcement, your work based on
+ the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+ 3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+ a) Accompany it with the complete corresponding machine-readable
+ source code, which must be distributed under the terms of Sections
+ 1 and 2 above on a medium customarily used for software interchange; or,
+
+ b) Accompany it with a written offer, valid for at least three
+ years, to give any third party, for a charge no more than your
+ cost of physically performing source distribution, a complete
+ machine-readable copy of the corresponding source code, to be
+ distributed under the terms of Sections 1 and 2 above on a medium
+ customarily used for software interchange; or,
+
+ c) Accompany it with the information you received as to the offer
+ to distribute corresponding source code. (This alternative is
+ allowed only for noncommercial distribution and only if you
+ received the program in object code or executable form with such
+ an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+ 4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+ 5. You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+ 6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+ 7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+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
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+ 8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+ 9. The Free Software Foundation may publish revised and/or new versions
+of the 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 a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation. If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+ 10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission. For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this. Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+ NO WARRANTY
+
+ 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, 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.
+
+ 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE 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.
+
+ 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
+convey 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 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.
+
+ 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 is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+ Gnomovision version 69, Copyright (C) <year> <name of author>
+ Gnomovision 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, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+ `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+ <signature of Ty Coon>, 1 April 1989
+ Ty Coon, President of Vice
+
+This 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.
+ GNU GENERAL PUBLIC LICENSE
+ Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.) 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
+this service 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 make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. 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.
+
+ We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+ Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+ Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ GNU GENERAL PUBLIC LICENSE
+ TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+ 0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License. The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language. (Hereinafter, translation is included without limitation in
+the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+ 1. You may copy and distribute 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 and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+ 2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+ a) You must cause the modified files to carry prominent notices
+ stating that you changed the files and the date of any change.
+
+ b) You must cause any work that you distribute or publish, that in
+ whole or in part contains or is derived from the Program or any
+ part thereof, to be licensed as a whole at no charge to all third
+ parties under the terms of this License.
+
+ c) If the modified program normally reads commands interactively
+ when run, you must cause it, when started running for such
+ interactive use in the most ordinary way, to print or display an
+ announcement including an appropriate copyright notice and a
+ notice that there is no warranty (or else, saying that you provide
+ a warranty) and that users may redistribute the program under
+ these conditions, and telling the user how to view a copy of this
+ License. (Exception: if the Program itself is interactive but
+ does not normally print such an announcement, your work based on
+ the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+ 3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+ a) Accompany it with the complete corresponding machine-readable
+ source code, which must be distributed under the terms of Sections
+ 1 and 2 above on a medium customarily used for software interchange; or,
+
+ b) Accompany it with a written offer, valid for at least three
+ years, to give any third party, for a charge no more than your
+ cost of physically performing source distribution, a complete
+ machine-readable copy of the corresponding source code, to be
+ distributed under the terms of Sections 1 and 2 above on a medium
+ customarily used for software interchange; or,
+
+ c) Accompany it with the information you received as to the offer
+ to distribute corresponding source code. (This alternative is
+ allowed only for noncommercial distribution and only if you
+ received the program in object code or executable form with such
+ an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+ 4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+ 5. You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+ 6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+ 7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+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
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+ 8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+ 9. The Free Software Foundation may publish revised and/or new versions
+of the 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 a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation. If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+ 10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission. For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this. Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+ NO WARRANTY
+
+ 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, 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.
+
+ 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE 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.
+
+ 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
+convey 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 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.
+
+ 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 is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+ Gnomovision version 69, Copyright (C) <year> <name of author>
+ Gnomovision 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, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+ `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+ <signature of Ty Coon>, 1 April 1989
+ Ty Coon, President of Vice
+
+This 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.
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