#!/usr/local/bin/perl5

# Try to identify a host's NIS domain name and NIS server by trying out a
# series of NIS domain name guesses. When the number of guesses becomes
# sufficiently large (say, several tens when the network is fast) the
# remote ypbind daemon may fall behind so far that it runs out of file
# descriptors.  This can be fixed by inserting sleep() calls.

$running_under_satan = 1;

require 'config/paths.pl';
require 'perl/fix_hostname.pl';
require 'perl/misc.pl';
require 'perllib/getopts.pl';

#
# Do JCL stuff.
#
$usage="Usage: $0 target [hints]\n";
&Getopts("d:v");

if ($#ARGV < 0) {
    print STDERR $usage;
    exit 1;
}
$target = $ARGV[0];
$service = &basename($0, ".satan");
$status = "a";

# Iterate over all hints. For each hint, try the hint itself, then all
# results from breaking it up at successive dots. We use an associative
# array to weed out duplicate guesses.
#
if ($opt_d) {
    $guesses{$opt_d} = 0;
} else {
    foreach $i (1..$#ARGV, 0) {
	$hint = $ARGV[$i];
	$guesses{$hint} = 0;
	for ($dot = rindex($hint,"."); $dot >= $[; $dot = rindex($head,".")) {
	    $head = substr($hint, $[, $dot - $[);
	    $guesses{$head} = 0;
	    $tail = substr($hint, $dot + 1);
	    $guesses{$tail} = 0;
	}
    }
}

foreach $guess (keys %guesses) {
    if (defined($opt_v)) {
	print STDERR "ypbind.satan: trying: $guess\n";
    }
    open (YPWHICH, "$YPWHICH -d $guess $target 2>/dev/null|") 
	|| exit 1;
    while (<YPWHICH>) {
	chop;
	$nis_server = &fix_hostname(&get_host_name($_), $target);
	$severity = "x";
	$trusted = "root\@$nis_server";
	$trustee = "root\@$target";
	$service_output = "$guess $nis_server";
	$text = "$nis_server serves nis domain $guess for $target";
	&satan_print();
	exit;
    }
    close (YPWHICH);
}

# All out guesses failed.

$text = "unable to guess nis domain name of $target";
&satan_print();
exit;