#!/usr/bin/perl
# Program to test forking and handles

use lib $ENV{"PF_ROOT"}."/bin";
use lib $ENV{"PF_ROOT"}."/modules";

use strict;
use DBI;
use POSIX qw(:signal_h :errno_h :sys_wait_h);

my $kidpid;
my $iKidCount = 0;
my %children;
my $hashChildren;
my $dbh;

$hashChildren = \%children;

# Get the initial database handle

$dbh = get_db_connection();
if ($dbh eq "") {
    print("Unable to connect to database\n");
    exit;
    }
LogThis("Test program starting up, processID is $$");

while(1) {
	CatchWindowsKids();
    $iKidCount++;
    LogThis("Forking child $iKidCount");

    # Disconnect from database before fork

    LogThis("Disconnecting database connection before fork", 3);
    $dbh->disconnect();
    undef($dbh);
    
    $kidpid = fork();

    # If it didn't work at all

    if (! defined($kidpid)) {
        die("Child process failed to fork");
        }

    # Reconnect to database

    $dbh = get_db_connection();
    if ($dbh eq "") {
        print("Unable to reconnect to database\n");
        exit;
        }

    # If we're the parent

    if ($kidpid != 0) {
        LogThis("Parent reconnected to database, database thread is ".$dbh->{'thread_id'});
        $hashChildren->{$iKidCount} = $kidpid;
        LogThis("We're the parent, sleeping for 1 second");
        sleep(1);
        next;
        }

    # Otherwise we're the child

    LogThis("Child reconnected to database, database thread is ".$dbh->{'thread_id'});
    LogThis("Succesfully forked child $iKidCount, process ID $$");
    $dbh->disconnect;
    undef($dbh);
    exit;
    }

sub CatchWindowsKids {
    my $iActiveKid;
    my $pid;

    foreach $iActiveKid(keys %children) {
        $pid = waitpid($hashChildren->{$iActiveKid}, &WNOHANG);
	if ($pid != -1) {
            LogThis("Caught child process ".$hashChildren->{$iActiveKid});
            delete($hashChildren->{$iActiveKid});
            }
        }
    return;
    }

sub LogThis {
    my @current_time;
    my $sFormattedTime;
 
    my ($sString) = @_;

    @current_time = localtime(time());
    $sFormattedTime = sprintf("%02s:%02s:%02s", @current_time[2], @current_time[1],@current_time[0]);
    print "$sFormattedTime $sString\n";
    return;
    }

sub get_db_connection {
    my $dsn;
    my $dbh;

    $dsn = "DBI:mysql:database=pathfinder";
    $dbh = DBI->connect($dsn, 'pflocal', 'pathfinder')
        || die "Unable to connect to database: $DBI::errstr";
    return($dbh);
    }