#! /usr/bin/perl
# to check ping from a file of hostnames using threads

#use strict;
use warnings;
use threads;
use threads::shared;
use Net::Ping;
use Time::HiRes;

my $timeout = 5;

print "\nEnter the host file name:";
chomp (my $host_file = <STDIN>);
open (HOSTFILE, "<", $host_file) or die "\nOpen of $host_file failed. $!";
my @host_array = <HOSTFILE>;
close (HOSTFILE);

print"\nEnter the output file name:";
chomp(my $out_file = <STDIN>);
open (OUTFILE, ">", $out_file) or die "\n Open of $out_file failed.$!";


my @threads;

foreach $addr(@host_array){

    chomp($addr);

    my $thr = threads->new(\&sub_ping,$addr);
    sleep(1);
    push(@threads,$thr);
}

foreach (@threads){
    my $val = $_->join();
    print "Trying to ping $val complete\n";
}

sub sub_ping {
    my $host= shift; #to get $ARGV[0]

    my $ping_handle = Net::Ping->new("icmp",$timeout) or die "\n ping unsuccessful. $!";;
    $ping_handle->hires();

    if (($host =~ m([a-zA-Z]+\.\w+\.\w+)) || ($host =~ m(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}))) {
        ($ret, $lat, $ip) = ($ping_handle->ping($host));

        if ($ret) {
            printf "$host \($ip\) responds to pings at %.2f msec.\n", ($lat//0)*1000;
            printf OUTFILE ("$host \($ip\) responds to pings at %.2f msec.\n",($lat//0)*1000);
        }
        else {
            printf "$host is NOT responding to pings. Time Taken %.2f msec\n",($lat//0)*1000;
            printf OUTFILE ("$host is NOT responding to pings. Time taken %.2f msec\n",($lat//0)*1000);
        }
        #$ping_handle->close();
    }
    else {
        print "$host is NOT a valid address.\n";
        print OUTFILE ("$host is NOT a valid address.\n");
    }
    return $host;
}