#! /usr/local/bin/perl

use Socket;

open (TEXT_FILE, "<test.txt"); 
open (MYFILE, '>>hosts2.cfg');

while ($line = <TEXT_FILE>) {
print MYFILE "$line";
        if ($line =~ m/host_name/) {
                $nextline = <TEXT_FILE> ;
		my $host = substr($line, 18);                
		$host = trim($host);
	        
		if ($nextline =~ m/address/) {
		#addres line already set
		#printf ("NextLine: . $nextline.");
		print MYFILE "$nextline";
		} else {
		#else we add the addres line, by doing a ping and getting the IP and inserting the address + result
		my $ip = host2ip($host);
		#print "IP: . $ip. \n";
		print "HOST: {$host} IP: {$ip} \n";
		print MYFILE "	address			        $ip\n";

		}		
	
        }
}
close (TEXT_FILE);
close (MYFILE);

sub host2ip {
#Perl function to get the IP from a hostname (should keep going even if there are errors!)
    my $host = shift;
    my $packed_addr = gethostbyname( $host );   
    
    die  "Hostname $host doesn't exist.\n" unless $packed_addr;    
    
 	return inet_ntoa( $packed_addr );
    
}

# Perl trim function to remove whitespace from the start and end of the string
sub trim($)
{
	my $string = shift;
	$string =~ s/^\s+//;
	$string =~ s/\s+$//;
	return $string;
}