#!/usr/bin/perl 

use strict;
use warnings;
use DBI;
use Data::Dumper;


if( $#ARGV < 0 ) {
        die "no sufficient argument.\n";
}
my $fork_count = shift;
#print STDERR $local_time."\n";
#print STDERR $execute_time."\n";

my $user="zivah";
my $password="zivah";
my $database="zivah";
my $schema="public";
my $server="192.168.1.40";
my $port="5432";

my $logfile="Log.txt";
my $LOG_FILE;
open ($LOG_FILE, ">$logfile") or die "Can't open the file, $!!\n";

$SIG{"ALRM"} = \&handler;

sub handler() {
        my $handle=$_[0];
        my $time=localtime;

        if($handle eq "ALRM") {
                print $LOG_FILE "SIGNAL SIG$handle is generated on $time -- $$\n";
                &Fork_Execute();
        }
}
my $Database_handler;
my $sth;

sub Database_Connect {
        # connect with database.
        #print "Connecting Database\n";
        unless( $Database_handler = DBI->connect("dbi:Pg:database=".$database.";host=$server;port=$port", $user, $password,  { RaiseError => 0, AutoCommit => 1, PrintError => 1, InactiveDestroy => 1, pg_server_prepare => 0}) ) {
                # Print an error message for unsuccessfull connection,
                print "EMERG: connect_database : connecting database failed, $DBI::errstr" ;
                # Return -1.
                return -1 ;
        }
        # Return the database handler.
        return $Database_handler;
}
sub Fork_Prepare {

        my ($result, $query, $return_value, $delete_time, @tables);
        # Prepare sql queries for finding unwanted tables.
        #$query="INSERT INTO $schema.a(name) values('santhosh');";
        my $id=shift;
        $query="Update $schema.a SET name='single',mtime=now() where no=$id;";
 unless($sth = $Database_handler->prepare($query)){
                # print an error message.
                print "ERROR:can't prepare SQL statement:[ $query ]:[$DBI::errstr]";
                # return -1.
                return -1;
        }

}

sub Fork_Execute {
        my ($result);
        unless($result = $sth->execute()){
                # Print an error message
                print "ERROR:can't execute SQL statement::[$DBI::errstr]";
                return -1;
        }

}
&Database_Connect();

my $fc=1;
my $cnt=1;
my @pids;
system("date");
while( $fork_count >= $fc ) {
        my $pid = fork();
        if (not defined $pid) {
                print "resources not avilable.\n";
        } elsif ($pid == 0) {
                &Fork_Prepare($cnt);
                #&Database_Connect();
                sleep(1000);
                exit;
        } else {
                $fc++;
                $cnt++;
                next;
        }
}
system("date");