make config handling more user friendly

readconfig.pl

@@ -1,11 +1,10 @@
-# 
 # SMArT
-# 
+#
 # Configuration file code
-# 
+#
 # Copyright 2001 Wilmer van der Gaast (lintux@lintux.cx)
-# 
-# 
+#
+#
 # 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
@@ -22,7 +21,7 @@
 #
 #
 
-my( @info, @conf, $l );
+my( @info, @conf, @rawconf, $l );
 
 $info[1] = 'Volume';
 $info[2] = 'Server name';
@@ -79,19 +78,25 @@ $info[400] = 'nwserv.stations file';
 $info[401] = 'Reply to nearest server requests';
 $info[402] = 'Reply to connect requests';
 
-open( CONF, '<' . $mars_config );
+open( CONF, '<' . $mars_config ) or die "Could not open $mars_config: $!";
 @conf = ();
+@rawconf = ();
+
 while( $l = <CONF> )
 {
-	$l =~ s/[\r\n]//g;
-	$l =~ s/[\t ]+/ /g;
-	$l =~ s/#.*//;
-	$l =~ s/^[\t ]*//;
-	$l =~ s/[\t ]*$//;
-	if( $l ne '' )
-	{
-		unshift( @conf, $l );
-	}
+    push( @rawconf, $l );
+
+    my $x = $l;
+    $x =~ s/[\r\n]//g;
+    $x =~ s/[\t ]+/ /g;
+    $x =~ s/#.*//;
+    $x =~ s/^[\t ]*//;
+    $x =~ s/[\t ]*$//;
+
+    if( $x ne '' )
+    {
+	push( @conf, $x );
+    }
 }
 close( CONF );
 
@@ -99,53 +104,163 @@ sortconfig();
 
 sub sortconfig()
 {
-	@conf = sort( { $a cmp $b } @conf );
-	@conf = sort( { ( split( ' ', $a ) )[0] <=> ( split( ' ', $b ) )[0] } @conf );
+    @conf = sort( { $a cmp $b } @conf );
+    @conf = sort( { ( split( ' ', $a ) )[0] <=> ( split( ' ', $b ) )[0] } @conf );
 }
 
 sub getconfigline( $ )
 {
-	my( @c, $c );
-	
-	@c = getconfig( @_ );
-	$c = $c[0];
-	$c =~ s/^[0-9]* //;
-	return( $c );
+    my( @c, $c );
+
+    @c = getconfig( @_ );
+    $c = $c[0];
+    $c =~ s/^[0-9]* //;
+    return( $c );
 }
 
 sub getconfig( $ )
 {
-	my( @c );
-	
-	@c = grep( /^$_[0] /i, @conf );
-	return( @c );
+    my( @c );
+
+    @c = grep( /^$_[0] /i, @conf );
+    return( @c );
 }
 
 sub addconfigline( $ )
 {
-	unshift( @conf, $_[0] );
+    unshift( @conf, $_[0] );
 }
 
 sub delconfigline( $ )
 {
-	@conf = grep( !/^$_[0] /i, grep( !/^$_[0]$/i, @conf ) );
+    @conf = grep( !/^$_[0] /i, grep( !/^$_[0]$/i, @conf ) );
+}
+
+sub normalize_line( $ )
+{
+    my $x = $_[0];
+
+    $x =~ s/[\r\n]//g;
+    $x =~ s/[\t ]+/ /g;
+    $x =~ s/#.*//;
+    $x =~ s/^[\t ]*//;
+    $x =~ s/[\t ]*$//;
+
+    return( $x );
+}
+
+sub section_of_line( $ )
+{
+    my $x = normalize_line( $_[0] );
+
+    if( $x =~ /^([0-9]+)\b/ )
+    {
+	return( $1 );
+    }
+
+    return( '' );
+}
+
+sub writeconfig_compact()
+{
+    my( $i, $l );
+
+    sortconfig();
+
+    open( CONF, '>' . $mars_config ) or die "Could not write $mars_config: $!";
+
+    $l = ( getconfig( '1 SYS' ) )[0];
+    delconfigline( '1 SYS' );
+    addconfigline( $l );
+
+    foreach $i ( @conf )
+    {
+	$l = $i;
+	$l =~ s/ .*//;
+	printf( CONF "%-50s    # %s\n", $i, $info[$l] );
+    }
+
+    close( CONF );
+}
+
+sub writeconfig_preserve_layout()
+{
+    my( %secmap, %written, @sections, $sec, $line, $sysline );
+
+    sortconfig();
+
+    # Keep SYS as the first entry in section 1.
+    $sysline = ( grep( /^1 SYS /, @conf ) )[0];
+    if( defined( $sysline ) )
+    {
+	@conf = grep( $_ ne $sysline, @conf );
+	unshift( @conf, $sysline );
+    }
+
+    foreach $line ( @conf )
+    {
+	$sec = section_of_line( $line );
+	if( $sec ne '' )
+	{
+	    push( @{ $secmap{$sec} }, $line );
+	}
+    }
+
+    open( CONF, '>' . $mars_config ) or die "Could not write $mars_config: $!";
+
+    foreach $line ( @rawconf )
+    {
+	$sec = section_of_line( $line );
+
+	# Preserve comments and blank lines exactly as they were.
+	if( $sec eq '' )
+	{
+	    print CONF $line;
+	    next;
+	}
+
+	# Replace each section only once, at its first occurrence.
+	if( ! $written{$sec} )
+	{
+	    if( defined( $secmap{$sec} ) )
+	    {
+		foreach my $entry ( @{ $secmap{$sec} } )
+		{
+		    print CONF $entry . "\n";
+		}
+	    }
+	    $written{$sec} = 1;
+	}
+
+	# Skip the original config line because the updated section
+	# has already been emitted.
+    }
+
+    # Append sections that did not exist in the original file.
+    @sections = sort { $a <=> $b } keys( %secmap );
+    foreach $sec ( @sections )
+    {
+	next if $written{$sec};
+
+	print CONF "\n";
+	foreach my $entry ( @{ $secmap{$sec} } )
+	{
+	    print CONF $entry . "\n";
+	}
+	$written{$sec} = 1;
+    }
+
+    close( CONF );
 }
 
 sub writeconfig()
 {
-	my( $i, $l );
-	
-	sortconfig();
-	
-	open( CONF, '>' . $mars_config );
-	$l = ( getconfig( '1 SYS' ) )[0];
-	delconfigline( '1 SYS' );
-	addconfigline( $l );
-	foreach $i ( @conf )
-	{
-		$l = $i;
-		$l =~ s/ .*//;
-		printf( CONF "%-50s    # %s\n", $i, $info[$l] );
-	}
-	close( CONF );
+    if( defined( $smart_compact_nwservconf ) && $smart_compact_nwservconf )
+    {
+	writeconfig_compact();
+    }
+    else
+    {
+	writeconfig_preserve_layout();
+    }
 }

smart.conf.cmake

@@ -37,6 +37,11 @@ $mars_config = '@MARS_NWE_INSTALL_FULL_CONFDIR@/nwserv.conf';
 # Keep this set to an unprivileged local account.
 $nonroot_user = 'nobody';
 
+# Write the mars_nwe configuration file in compact form.
+# 0 = preserve comments, blank lines and the original section layout
+# 1 = write a compact configuration file without the original long comments
+$smart_compact_nwservconf = 0;
+
 # ------------------------------------------------------------
 # SMArT internal file layout
 # ------------------------------------------------------------