ChangeLog

@@ -1,22 +1,12 @@
-2025-01-02  Antonio Diaz Diaz  <antonio@gnu.org>
-
-	* Version 1.5 released.
-	* lzd.cc: Reject empty members and nonzero first LZMA byte.
-
-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 LZMA byte explicitly.
+	* 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.
+	* lzd.cc (main): Verify 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.
@@ -33,7 +23,7 @@
 
 	* Version 1.0 released.
 	* lzd.cc: Minor code improvements.
-	* check.sh: Require a POSIX shell.
+	* check.sh: A POSIX shell is required to run the tests.
 
 2016-05-10  Antonio Diaz Diaz  <antonio@gnu.org>
 
@@ -80,7 +70,8 @@
 	* Version 0.1 released.
 
 
-Copyright (C) 2013-2025 Antonio Diaz Diaz.
+Copyright (C) 2013-2022 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.
+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.

INSTALL

@@ -4,8 +4,7 @@ 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
-Lzip is available at http://www.nongnu.org/lzip/lzip.html
+Gcc is available at http://gcc.gnu.org.
 
 
 Procedure
@@ -32,8 +31,7 @@ extracted from the archive.
 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.
+   documentation.
 
 
 Another way
@@ -53,7 +51,7 @@ After running 'configure', you can run 'make' and 'make install' as
 explained above.
 
 
-Copyright (C) 2013-2025 Antonio Diaz Diaz.
+Copyright (C) 2013-2022 Antonio Diaz Diaz.
 
 This file is free documentation: you have unlimited permission to copy,
 distribute, and modify it.

Makefile.in

@@ -2,8 +2,8 @@
 DISTNAME = $(pkgname)-$(pkgversion)
 INSTALL = install
 INSTALL_PROGRAM = $(INSTALL) -m 755
-INSTALL_DIR = $(INSTALL) -d -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
 
@@ -24,24 +24,21 @@ $(progname) : $(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 : ;
-MAKEFLAGS += -r
-.SUFFIXES :
-
 $(objs) : Makefile
 
+
 doc :
 
 info : $(VPATH)/doc/$(pkgname).info
 
 $(VPATH)/doc/$(pkgname).info : $(VPATH)/doc/$(pkgname).texi
-	cd $(VPATH)/doc && $(MAKEINFO) $(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)
+	help2man -n 'educational decompressor for the lzip format' \
+	  -o $@ --no-info ./$(progname)
 
 Makefile : $(VPATH)/configure $(VPATH)/Makefile.in
 	./config.status
@@ -108,10 +105,10 @@ dist : doc
 	  $(DISTNAME)/*.cc \
 	  $(DISTNAME)/testsuite/check.sh \
 	  $(DISTNAME)/testsuite/test.txt \
-	  $(DISTNAME)/testsuite/em.lz \
 	  $(DISTNAME)/testsuite/fox.lz \
 	  $(DISTNAME)/testsuite/fox_*.lz \
-	  $(DISTNAME)/testsuite/test.txt.lz
+	  $(DISTNAME)/testsuite/test.txt.lz \
+	  $(DISTNAME)/testsuite/test_em.txt.lz
 	rm -f $(DISTNAME)
 	lzip -v -9 $(DISTNAME).tar
 

NEWS

@@ -1,7 +1,5 @@
-Changes in version 1.5:
+Changes in version 1.3:
 
-lzd now exits with error status 2 if any empty member is found in a
-multimember file.
-
-lzd now exits with error status 2 if the first byte of the LZMA stream is
-not 0.
+Lzd now discards the first byte of the LZMA stream explicity (instead of
+shifting 1 extra byte in the initialization of 'code') to make the intent
+clearer.

README

@@ -1,5 +1,3 @@
-See the file INSTALL for compilation and installation instructions.
-
 Description
 
 Lzd is a simplified decompressor for the lzip format with an educational
@@ -9,7 +7,7 @@ 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.
+lzip specification; it verifies the 3 integrity factors.
 
 The source code of lzd is also used as a reference in the description of the
 media type 'application/lzip'.
@@ -20,9 +18,33 @@ 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
+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 checked.
+data. Integrity of such concatenated compressed input is also verified.
+
+The lzip file format is designed for data sharing and long-term archiving,
+taking into account both data integrity and decoder availability:
+
+   * The lzip format provides very safe integrity checking and some data
+     recovery means. The program lziprecover can repair bit flip errors
+     (one of the most common forms of data corruption) in lzip files, and
+     provides data recovery capabilities, including error-checked merging
+     of damaged copies of a file.
+
+   * The lzip format is as simple as possible (but not simpler). The lzip
+     manual provides the source code of a simple decompressor along with a
+     detailed explanation of how it works, so that with the only help of the
+     lzip manual it would be possible for a digital archaeologist to extract
+     the data from a lzip file long after quantum computers eventually
+     render LZMA obsolete.
+
+   * Additionally the lzip reference implementation is copylefted, which
+     guarantees that it will remain free forever.
+
+A nice feature of the lzip format is that a corrupt byte is easier to repair
+the nearer it is from the beginning of the file. Therefore, with the help of
+lziprecover, losing an entire archive just because of a corrupt byte near
+the beginning is a thing of the past.
 
 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
@@ -30,10 +52,11 @@ 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) 2013-2025 Antonio Diaz Diaz.
+Copyright (C) 2013-2022 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.
+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.

configure

@@ -1,12 +1,12 @@
 #! /bin/sh
 # configure script for Lzd - Educational decompressor for the lzip format
-# Copyright (C) 2013-2025 Antonio Diaz Diaz.
+# Copyright (C) 2013-2022 Antonio Diaz Diaz.
 #
 # This configure script is free software: you have unlimited permission
 # to copy, distribute, and modify it.
 
 pkgname=lzd
-pkgversion=1.5
+pkgversion=1.3
 progname=lzd
 srctrigger=lzd.cc
 
@@ -24,7 +24,6 @@ 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 ; }
@@ -66,11 +65,10 @@ while [ $# != 0 ] ; do
 		echo "  --infodir=DIR         info files directory [${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 "  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 "  LDFLAGS=OPTIONS       command line options for the linker [${LDFLAGS}]"
 		echo
 		exit 0 ;;
 	--version | -V)
@@ -98,7 +96,6 @@ while [ $# != 0 ] ; do
 	CXXFLAGS=*)  CXXFLAGS=${optarg} ;;
 	CXXFLAGS+=*) CXXFLAGS="${CXXFLAGS} ${optarg}" ;;
 	LDFLAGS=*)    LDFLAGS=${optarg} ;;
-	MAKEINFO=*)  MAKEINFO=${optarg} ;;
 
 	--*)
 		echo "configure: WARNING: unrecognized option: '${option}'" 1>&2 ;;
@@ -109,7 +106,7 @@ while [ $# != 0 ] ; do
 		exit 1 ;;
 	esac
 
-	# Check whether the option took a separate argument
+	# 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
@@ -150,7 +147,7 @@ if [ -z "${no_create}" ] ; then
 # This script is free software: you have unlimited permission
 # to copy, distribute, and modify it.
 
-exec /bin/sh "$0" ${args} --no-create
+exec /bin/sh $0 ${args} --no-create
 EOF
 	chmod +x config.status
 fi
@@ -167,11 +164,10 @@ 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) 2013-2025 Antonio Diaz Diaz.
+# Copyright (C) 2013-2022 Antonio Diaz Diaz.
 # This file was generated automatically by configure. Don't edit.
 #
 # This Makefile is free software: you have unlimited permission
@@ -191,7 +187,6 @@ CXX = ${CXX}
 CPPFLAGS = ${CPPFLAGS}
 CXXFLAGS = ${CXXFLAGS}
 LDFLAGS = ${LDFLAGS}
-MAKEINFO = ${MAKEINFO}
 EOF
 cat "${srcdir}/Makefile.in" >> Makefile
 

debian/changelog

@@ -1,29 +1,3 @@
-lzd (1.5-1) sid; urgency=medium
-
-  * Uploading to sid.
-  * Merging upstream version 1.5.
-  * Correcting public-domain identifier in copyright.
-
- -- Daniel Baumann <daniel.baumann@progress-linux.org>  Tue, 14 Jan 2025 11:09:08 +0100
-
-lzd (1.4-2) sid; urgency=medium
-
-  * Uploading to sid.
-  * Updating years in copyright for 2024.
-  * Updating to standards-version 4.7.0.
-
- -- Daniel Baumann <daniel.baumann@progress-linux.org>  Thu, 25 Jul 2024 06:37:01 +0200
-
-lzd (1.4-1) sid; urgency=medium
-
-  * Uploading to sid.
-  * Merging upstream version 1.4.
-  * Refreshing build.patch.
-  * Disabling testsuite for now as the current upstream release misses
-    some files for it to run at all.
-
- -- Daniel Baumann <daniel.baumann@progress-linux.org>  Tue, 23 Jan 2024 06:17:15 +0100
-
 lzd (1.3-2) sid; urgency=medium
 
   * Uploading to sid.

debian/control

@@ -5,7 +5,7 @@ Maintainer: Daniel Baumann <daniel.baumann@progress-linux.org>
 Build-Depends:
  debhelper-compat (= 13),
 Rules-Requires-Root: no
-Standards-Version: 4.7.0
+Standards-Version: 4.6.2
 Homepage: http://www.nongnu.org/lzip/lzd.html
 Vcs-Browser: https://git.progress-linux.org/users/daniel.baumann/debian/packages/lzd
 Vcs-Git: https://git.progress-linux.org/users/daniel.baumann/debian/packages/lzd

debian/copyright

@@ -4,14 +4,14 @@ Upstream-Contact: lzip-bug@nongnu.org
 Source: https://download.savannah.gnu.org/releases/lzip/
 
 Files: *
-Copyright: 2013-2024 Antonio Diaz Diaz <ant_diaz@teleline.es>
-License: public-domain
+Copyright: 2013-2022 Antonio Diaz Diaz <ant_diaz@teleline.es>
+License: PD
 
 Files: debian/*
-Copyright: 2013-2024 Daniel Baumann <daniel.baumann@progress-linux.org>
-License: public-domain
+Copyright: 2013-2022 Daniel Baumann <daniel.baumann@progress-linux.org>
+License: PD
 
-License: public-domain
+License: PD
  This program is free software: you have unlimited permission
  to copy, distribute and modify it.
  .

debian/patches/debian/0001-build.patch

@@ -4,18 +4,16 @@ Description: Avoid overwriting build-environment.
 diff -Naurp lzd.orig/configure lzd/configure
 --- lzd.orig/configure
 +++ lzd/configure
-@@ -20,10 +20,10 @@ bindir='$(exec_prefix)/bin'
- datarootdir='$(prefix)/share'
+@@ -21,9 +21,9 @@ datarootdir='$(prefix)/share'
  infodir='$(datarootdir)/info'
  mandir='$(datarootdir)/man'
--CXX=g++
+ CXX=g++
 -CPPFLAGS=
 -CXXFLAGS='-Wall -W -O2'
 -LDFLAGS=
-+#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 ; }

debian/rules

@@ -10,6 +10,3 @@ override_dh_auto_configure:
 
 override_dh_auto_install:
 	dh_auto_install -- DESTDIR=$(CURDIR)/debian/lzd
-
-override_dh_auto_test:
-	# disabled: incomplete upstream testsuite

lzd.cc

@@ -1,5 +1,5 @@
 /* Lzd - Educational decompressor for the lzip format
-   Copyright (C) 2013-2025 Antonio Diaz Diaz.
+   Copyright (C) 2013-2022 Antonio Diaz Diaz.
 
    This program is free software. Redistribution and use in source and
    binary forms, with or without modification, are permitted provided
@@ -18,7 +18,7 @@
 */
 /*
    Exit status: 0 for a normal exit, 1 for environmental problems
-   (file not found, invalid command-line options, I/O errors, etc), 2 to
+   (file not found, invalid command line options, I/O errors, etc), 2 to
    indicate a corrupt or invalid input file.
 */
 
@@ -130,11 +130,10 @@ public:
 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];
+typedef uint8_t Lzip_header[6];		// 0-3 magic bytes
+					//   4 version
+					//   5 coded dictionary size
+typedef uint8_t Lzip_trailer[20];
 			//  0-3  CRC32 of the uncompressed data
 			//  4-11 size of the uncompressed data
 			// 12-19 member size including header and trailer
@@ -146,11 +145,9 @@ class Range_decoder
   uint32_t range;
 
 public:
-  Range_decoder()
-    : member_pos( header_size ), code( 0 ), range( 0xFFFFFFFFU )
+  Range_decoder() : member_pos( 6 ), code( 0 ), range( 0xFFFFFFFFU )
     {
-    if( get_byte() != 0 )		// check first LZMA byte
-      { std::fputs( "Nonzero first LZMA byte.\n", stderr ); std::exit( 2 ); }
+    get_byte();			// discard first byte of the LZMA stream
     for( int i = 0; i < 4; ++i ) code = ( code << 8 ) | get_byte();
     }
 
@@ -171,9 +168,9 @@ public:
     return symbol;
     }
 
-  bool decode_bit( Bit_model & bm )
+  unsigned decode_bit( Bit_model & bm )
     {
-    bool symbol;
+    unsigned symbol;
     const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
     if( code < bound )
       {
@@ -219,8 +216,8 @@ public:
     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] );
+      const unsigned match_bit = ( match_byte >> i ) & 1;
+      const unsigned bit = decode_bit( bm[symbol+(match_bit<<8)+0x100] );
       symbol = ( symbol << 1 ) | bit;
       if( match_bit != bit )
         {
@@ -235,12 +232,11 @@ public:
   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 );
+      return decode_tree( lm.bm_low[pos_state], len_low_bits );
     if( decode_bit( lm.choice2 ) == 0 )
-      return min_match_len + len_low_symbols +
+      return len_low_symbols +
              decode_tree( lm.bm_mid[pos_state], len_mid_bits );
-    return min_match_len + len_low_symbols + len_mid_symbols +
+    return len_low_symbols + len_mid_symbols +
            decode_tree( lm.bm_high, len_high_bits );
     }
   };
@@ -375,12 +371,12 @@ bool LZ_decoder::decode_member()	// Return false if error
         rep0 = distance;
         }
       state.set_rep();
-      len = rdec.decode_len( rep_len_model, pos_state );
+      len = min_match_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 );
+      len = min_match_len + rdec.decode_len( match_len_model, pos_state );
       const int len_state = std::min( len - min_match_len, len_states - 1 );
       rep0 = rdec.decode_tree( bm_dis_slot[len_state], dis_slot_bits );
       if( rep0 >= start_dis_model )
@@ -393,12 +389,13 @@ bool LZ_decoder::decode_member()	// Return false if error
                                              direct_bits );
         else
           {
-          rep0 += rdec.decode( direct_bits-dis_align_bits ) << dis_align_bits;
+          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
+            return ( len == min_match_len );	// End Of Stream marker
             }
           }
         }
@@ -423,10 +420,10 @@ int main( const int argc, const char * const argv[] )
       "See the lzip manual for an explanation of the code.\n"
       "\nUsage: %s [-d] < file.lz > file\n"
       "Lzd decompresses from standard input to standard output.\n"
-      "\nCopyright (C) 2025 Antonio Diaz Diaz.\n"
+      "\nCopyright (C) 2022 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"
+      "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"
       "Lzd home page: http://www.nongnu.org/lzip/lzd.html\n",
       PROGVERSION, argv[0] );
@@ -438,11 +435,10 @@ int main( const int argc, const char * const argv[] )
   setmode( STDOUT_FILENO, O_BINARY );
 #endif
 
-  bool empty = false, multi = false;
   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 );
+    Lzip_header header;				// verify header
+    for( int i = 0; i < 6; ++i ) header[i] = std::getc( stdin );
     if( std::feof( stdin ) || std::memcmp( header, "LZIP\x01", 5 ) != 0 )
       {
       if( first_member )
@@ -453,40 +449,37 @@ int main( const int argc, const char * const argv[] )
     unsigned dict_size = 1 << ( header[5] & 0x1F );
     dict_size -= ( dict_size / 16 ) * ( ( header[5] >> 5 ) & 7 );
     if( dict_size < min_dictionary_size || dict_size > max_dictionary_size )
-      { std::fputs( "Invalid dictionary size in member header.\n",
-                    stderr ); return 2; }
+      { std::fputs( "Invalid dictionary size in member header.\n", stderr );
+        return 2; }
 
     LZ_decoder decoder( dict_size );		// decode LZMA stream
     if( !decoder.decode_member() )
-      { std::fputs( "Data error.\n", stderr ); return 2; }
+      { 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();
+    Lzip_trailer trailer;			// verify trailer
+    for( int i = 0; i < 20; ++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; }
+      { 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; }
-    multi = !first_member; if( data_size == 0 ) empty = true;
+      { 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; }
+      { 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; }
-  if( empty && multi )
-    { std::fputs( "Empty member not allowed.\n", stderr ); return 2; }
   return 0;
   }

testsuite/check.sh

@@ -1,6 +1,6 @@
 #! /bin/sh
 # check script for Lzd - Educational decompressor for the lzip format
-# Copyright (C) 2013-2025 Antonio Diaz Diaz.
+# Copyright (C) 2013-2022 Antonio Diaz Diaz.
 #
 # This script is free software: you have unlimited permission
 # to copy, distribute, and modify it.
@@ -30,9 +30,8 @@ cd "${objdir}"/tmp || framework_failure
 
 in="${testdir}"/test.txt
 in_lz="${testdir}"/test.txt.lz
-em_lz="${testdir}"/em.lz
+in_em="${testdir}"/test_em.txt.lz
 fox_lz="${testdir}"/fox.lz
-fnz_lz="${testdir}"/fox_nz.lz
 fail=0
 test_failed() { fail=1 ; printf " $1" ; [ -z "$2" ] || printf "($2)" ; }
 
@@ -41,41 +40,25 @@ printf "testing lzd-%s..." "$2"
 "${LZIP}" < "${in}" 2> /dev/null
 [ $? = 2 ] || test_failed $LINENO
 
-"${LZIP}" < "${in_lz}" > out || test_failed $LINENO
-cmp "${in}" out || test_failed $LINENO
+for i in "${in_lz}" "${in_em}" ; do
+	"${LZIP}" < "$i" > copy || test_failed $LINENO "$i"
+	cmp "${in}" copy || 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}" "${in_lz}" | "${LZIP}" > copy2 || test_failed $LINENO
+cmp in2 copy2 || test_failed $LINENO
+rm -f copy2 || 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 $LINENO
-rm -f in2 out2 out2.lz || framework_failure
-
-touch empty || framework_failure
-"${LZIP}" -d < "${em_lz}" > em || test_failed $LINENO
-cmp empty em || test_failed $LINENO
+cat "${in_lz}" "${in_lz}" > copy2.lz || framework_failure
+printf "\ngarbage" >> copy2.lz || framework_failure
+"${LZIP}" -d < copy2.lz > copy2 || test_failed $LINENO
+cmp in2 copy2 || test_failed $LINENO
+rm -f in2 copy2 copy2.lz || framework_failure
 
 printf "\ntesting bad input..."
 
-cat "${em_lz}" "${em_lz}" | "${LZIP}" -d > em 2> /dev/null
-[ $? = 2 ] || test_failed $LINENO
-cmp empty em || test_failed $LINENO
-rm -f empty em || framework_failure
-cat "${em_lz}" "${in_lz}" | "${LZIP}" -d > out 2> /dev/null
-[ $? = 2 ] || test_failed $LINENO
-cmp "${in}" out || test_failed $LINENO
-cat "${in_lz}" "${em_lz}" | "${LZIP}" -d > out 2> /dev/null
-[ $? = 2 ] || test_failed $LINENO
-cmp "${in}" out || test_failed $LINENO
-
-"${LZIP}" < "${fnz_lz}" 2> /dev/null
-[ $? = 2 ] || test_failed $LINENO
-
-for i in fox_v2.lz fox_s11.lz fox_de20.lz \
+for i in fox_bm.lz fox_v2.lz fox_s11.lz fox_de20.lz \
          fox_bcrc.lz fox_crc0.lz fox_das46.lz fox_mes81.lz ; do
 	"${LZIP}" < "${testdir}"/$i > /dev/null 2>&1
 	[ $? = 2 ] || test_failed $LINENO $i
@@ -87,29 +70,29 @@ for i in fox_bcrc.lz fox_crc0.lz fox_das46.lz fox_mes81.lz ; do
 	[ $? = 2 ] || test_failed $LINENO $i
 	cmp fox out || test_failed $LINENO $i
 done
-rm -f fox || framework_failure
+rm -f fox out || framework_failure
 
 cat "${in_lz}" "${in_lz}" > in2.lz || framework_failure
 cat "${in_lz}" "${in_lz}" "${in_lz}" > in3.lz || framework_failure
-if dd if=in3.lz of=trunc.lz bs=14682 count=1 2> /dev/null &&
-   [ -e trunc.lz ] && cmp in2.lz trunc.lz ; then
+if dd if=in3.lz of=trunc.lz bs=14752 count=1 2> /dev/null &&
+   [ -e trunc.lz ] && cmp in2.lz trunc.lz > /dev/null 2>&1 ; then
 # can't detect truncated header of non-first member
-	for i in 6 20 14664 14688 ; do
+	for i in 6 20 14734 14758 ; do
 		dd if=in3.lz of=trunc.lz bs=$i count=1 2> /dev/null
 		"${LZIP}" < trunc.lz > /dev/null 2>&1
 		[ $? = 2 ] || test_failed $LINENO $i
 	done
 else
-	printf "warning: skipping truncation test: 'dd' does not work on your system."
+	printf "\nwarning: skipping truncation test: 'dd' does not work on your system."
 fi
 rm -f in2.lz in3.lz trunc.lz || framework_failure
 
-cp "${in_lz}" ingin.lz || framework_failure
+cat "${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 $LINENO
-rm -f out ingin.lz || framework_failure
+"${LZIP}" -d < ingin.lz > copy || test_failed $LINENO
+cmp "${in}" copy || test_failed $LINENO
+rm -f copy ingin.lz || framework_failure
 
 echo
 if [ ${fail} = 0 ] ; then

testsuite/test.txt

@@ -1,7 +1,8 @@
                     GNU GENERAL PUBLIC LICENSE
                        Version 2, June 1991
 
- Copyright (C) 1989, 1991 Free Software Foundation, Inc. <http://fsf.org/>
+ 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.
 
@@ -338,7 +339,8 @@ Public License instead of this License.
                     GNU GENERAL PUBLIC LICENSE
                        Version 2, June 1991
 
- Copyright (C) 1989, 1991 Free Software Foundation, Inc. <http://fsf.org/>
+ 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.