File Coverage

blib/lib/Proc/Branch.pm

Criterion	Covered	Total	%
statement	9	49	18.3
branch	0	22	0.0
condition	0	5	0.0
subroutine	3	8	37.5
pod	4	4	100.0
total	16	88	18.1

package Proc::Branch;

use strict;
use warnings;
use Carp;

our $VERSION = '0.01';

sub new {
    my $class = shift;
    my %arg = (
        'branch' => 2,
        'sleep'  => 0,
        'debug'  => 0,
        'auto_merge' => 1,
        @_,
    );

    my $debug = $arg{debug};

    my @pid;
    if ( ( my $n = $arg{branch} - 1 ) > 0 ) {
        while ( $n >= 1 ) {
            my $pid = fork;
            if ( not defined $pid ) {
                carp "ERROR: cannot fork\n" if ( $debug );
                return;
            }
            elsif ( $pid == 0 ) {
                # child process
                print "INFO($class): Child process($$) launches.\n"
                    if ( $debug );
                $arg{proc} = int $n;
                return bless( \%arg, __PACKAGE__ );
            }
            else {
                # parent
                push @pid, $pid;
                $n--;
                sleep $arg{'sleep'};
            }
        }
    }

    print "INFO($class): Branching is completed.\n"
        if ( $debug );
    $arg{proc} = 0;
    $arg{pid} = \@pid;

    return bless( \%arg, $class );
}

sub proc {
    my $self = shift;
    return $self->{proc};
}

sub merge {
    my $self = shift;
    my $exit = shift || 0;

    $self->{auto_merge} = 0;

    my $debug = $self->{debug};

    if ( $self->{proc} ) {
        print "INFO(" . __PACKAGE__ . "): Child process($$) exits.\n"
            if ( $debug );
        exit($exit);
    }
    else {
        # waitpid
        for ( @{ $self->{pid} } ) {
            print "INFO(" . __PACKAGE__ . "): Waiting for child process($_).\n"
                if ( $debug );
            waitpid $_, 0;
        }
    }
}

sub pid {
    my $self = shift;
    my $proc = shift;

    return if ( !defined $proc or $proc < 1 );
    return $self->{pid}[$proc-1];
}

sub DESTROY {
    my $self = shift;
    if ( $self->{auto_merge} ) {
        $self->merge;
    }
}

1;
__END__