#!/usr/bin/perl

$base= "/var/named";
$conf= "$base/conf";
$etcfile= "/etc/named/zones-rgc";

$check= 1;
$progress= 1;

while ($ARGV[0] =~ m/^\-/) {
    $_= shift @ARGV;
    last if m/^\-\-?$/;
    while (m/^\-./) {
	if (s/^\-f/-/) { $usage=0; $check=0; $install++; }
	elsif (s/^\-y/-/) { $usage=0; $check=1; $install++; }
	elsif (s/^\-n/-/) { $usage=0; $check=1; $install=0; }
	elsif (s/^\-h/-/) { $hostdelg=1; $hostzone=0; }
	elsif (s/^\-z/-/) { $hostdelg=1; $hostzone=1; }
	elsif (s/^\-q/-/) { $progress=0; }
	else { $usage=1; break; }
    }
}

die
"usage: named-conf-regen -f|-y|-n [-h|-z]\n".
"operation modes:\n".
" -f   install without checking     -ff  and then ndc reload\n".
" -y   check and install            -yy  and then ndc reload\n".
" -n   check only\n".
"additional options:\n".
" -h   check output from host -C\n".
" -z   check output from host -C and host -val\n".
    if $usage;

beginfile('secondary.zones');
open E, "< $etcfile" or die "$0: open $etcfile: $!\n";
for (;;) {
    $!=0; defined $_=<E> or die "$0: read $etcfile $!\n";
    s/^\s+//; chomp; s/\s+$//;
    next if m/^\#/;
    last if m/^end$/;
    if (m/^myname\s+(\S.*\S)/) {
	@mynames= split /\s+/, $1;
    } elsif (m/^(secondary|backup|unoff)\s+(\S+)\s+([0-9. \t]+)$/) {
	$style= $1;
	$zone= $2;
	@servers= split /\s+/, $3;
	$file= "slave/$zone";
	progress();
	check();
    } else {
	die "$0: $etcfile:$.: syntax error in \`$_'\n";
    }
}

sub lookup ($$) {
    my ($type,$domain) = @_;
    my ($c,@result);
    defined($c=open ADH, "-|") or die "$0: fork adnshost: $!\n";
    if (!$c) {
	exec 'adnshost','+Do','+Dt','+Dc','-Cf',"-t$type",
	     '-',"$domain.";
	die "$0: exec adnshost: $!\n";
    }
    @result= <ADH>;
    chomp @result;
    $!=0; close ADH;
    die "$0: lookup -t$type $domain failed $? $!\n" if $? or $!;
    return @result;
}

sub lookup1 ($$) {
    my ($type,$domain) = @_;
    my (@result)= lookup($type,$domain);
    @result==1 or die "$0: lookup -t$type $domain gave more than one RR\n";
    return $result[0];
}

sub check () {
    return unless $check;
    eval {
	$soa= lookup1('soa',$zone);
	$soa_origin=$soa; $soa_origin =~ s/ .*//;
	$soa_origin_addr= lookup1('a',$soa_origin);

	@zone_ns= lookup('ns-',$zone);

	@ok_sources= ($soa_origin_addr);
	$ok_sources_descr= "SOA ORIGIN $soa_origin [$soa_origin_addr]";

	if ($style eq 'unoff' || $style eq 'backup') {
	    for $zone_ns (@zone_ns) {
		@zone_ns_addrs= lookup('a',$zone_ns);
		push @ok_sources, @zone_ns_addrs;
		$ok_sources_descr.= ", NS $zone_ns [@zone_ns_addrs]";
	    }
	}

	for $server (@servers) {
	    grep { $server eq $_ } @ok_sources
		or warn "secondarying from $server which is not ".
		        "$ok_sources_desc\n";
	}

	if ($style eq 'secondary') {
	    grep { $zone_ns=$_, grep { $myname eq $_ } @mynames } @zone_n
		or warn "supposedly published secondary but we ".
		        "(@mynames) are not published ($@zone_ns)\n";
	}
    }
    check_after_eval();
    

			 
#	$superzone= $zone; $superzone =~ s/^[^\.]+\.//;
#	@super_ns= lookup('ns-',$zone);
    }

    eval {

	for $super_ns (@super_ns) {
	    @deleg_ns= ();
	    open DIG, "dig @$super_ns. -t ns +norecurse $zone."
		or die "$0: fork for dig: $!\n";
	    while (<DIG>) {
		

	    split /\n/, lookup("
	
		case "$style" in
		secondary|backup)
			if [ $meadvert = 0 ]
			then
				warning "$myname unlisted NS $nsnames"
			fi
			;;
		unoff)
			if $meadvert = 0
			then
				warning "$myname advertised NS $nsnames"
			fi
			;;
		esac

		addrs=''
		for ns in $names
		do
			set -e; a="`host -t a \"$ns\".`"; set +e
			taddrs="`echo \" $a\" | expand | sed -n '
				 1s/^ //
				s/^[^ ][^ ]*  *A  *\([0-9][.0-9]*\)/\1/p
			'`"
			equlines "A $ns" "$a" "$taddrs"
			addrs="$addrs $taddrs"
		done
	fi

	cat <<END
zone "$zone" {
	type slave;
	file "$file";
	masters {
END
	for server in $servers
	do
		echo "		$server;"
		if $check
		then
			notfound=1
			for addr in $addrs
			do
				if [ "x$addr" = "x$server" ]
				then
					notfound=0
				fi
			done
			if $notfound
			then
 warning "server $server? but $rectype $names" $addrs
			fi
		fi
	done
	cat <<END
	};
};
END
	hostfirstwarn=1
	if $hostdelg
	then
		checkhostout -C
	fi
	if $hostzone
	then
		checkhostout -val localhost
	fi
done
endfile

    
chdir "$base/primary" or die "$0: chdir $base/primary: $!";
beginfile('primary.zones');

for $f (<*_db>) {
    $zone= $f; $zone =~ s/_db$//;
    

for f in $zones
do
	zone="`echo $f | sed -e 's/_db$//'`"
	cat <<END
zone "$zone" {
	type master;
	file "primary/$f";
};
END
done
endfile


    
sub beginfile ($) {
    $currentfile= $_[0];
    $currentfile_opened= $install ? "$conf/$currentfile.new" : "/dev/null";
    open CFF, "> $toopen" or die "$0: begin $currentfile_opened: $!\n";
}

endfile () {
    close CFF or die "$0: close $currentfile_opened: $!\n";
    push @files, $currentfile;
}

sub installfiles () {
    return unless $install;
    chdir $conf or die "$0: chdir $conf: $!\n";
    for $f (@files) {
	rename "$f.new", $f or die "$0: install new $f: $!\n";
    }
}

warning () {
	echo >&2 "$zone $style: $*"
	warnings=$[$warnings+1]
}

equlines () {
	if [ "x`echo \" $2\" | wc -l`" != "x`echo \" $3\" | wc -l`" ]
	then
		warning "$1 >$2|$3<"
	fi
}

checkhostout () {
	set +e
	hostout="`host $1 \"$zone\" 2>&1 >/dev/null $2 | egrep -v \
'^ \!\!\! .* SOA primary .* is not advertised via NS$'`"
	set -e
	if [ "x$hostout" = x ]; then return; fi
	if $hostfirstwarn
	then
		warning "warnings from host:"
		hostfirstwarn=0
	fi
	echo >&2 "$hostout"
}

progress () {
	if $progress
	then
		echo -n "$zone $style                    " >&2
		echo -ne '\r' >&2
	fi
}

myname=''

if [ $warnings != 0 ]
then
	echo >&2 "$warnings warnings                                        "
fi

installfiles