Initial commit of OpenSPARC T2 architecture model.

[OpenSPARC-T2-SAM] / sam-t2 / devtools / v8plus / lib / perl5 / 5.8.8 / Net / Time.pm

# Net::Time.pm
#
# Copyright (c) 1995-2004 Graham Barr <gbarr@pobox.com>. All rights reserved.
# This program is free software; you can redistribute it and/or
# modify it under the same terms as Perl itself.

package Net::Time;

use strict;
use vars qw($VERSION @ISA @EXPORT_OK $TIMEOUT);
use Carp;
use IO::Socket;
require Exporter;
use Net::Config;
use IO::Select;

@ISA = qw(Exporter);
@EXPORT_OK = qw(inet_time inet_daytime);

$VERSION = "2.10";

$TIMEOUT = 120;

sub _socket
{
my($pname,$pnum,$host,$proto,$timeout) = @_;

$proto ||= 'udp';

my $port = (getservbyname($pname, $proto))[2] || $pnum;

my $hosts = defined $host ? [ $host ] : $NetConfig{$pname . '_hosts'};

my $me;

foreach $host (@$hosts)
 {
  $me = IO::Socket::INET->new(PeerAddr => $host,
                              PeerPort => $port,
                              Proto    => $proto
                             ) and last;
 }

return unless $me;

$me->send("\n")
       if $proto eq 'udp';

$timeout = $TIMEOUT
       unless defined $timeout;

IO::Select->new($me)->can_read($timeout)
       ? $me
       : undef;
}

sub inet_time
{
my $s = _socket('time',37,@_) || return undef;
my $buf = '';
my $offset = 0 | 0;

return undef
       unless defined $s->recv($buf, length(pack("N",0)));

# unpack, we | 0 to ensure we have an unsigned
my $time = (unpack("N",$buf))[0] | 0;

# the time protocol return time in seconds since 1900, convert
# it to a the required format

if($^O eq "MacOS") {
  # MacOS return seconds since 1904, 1900 was not a leap year.
  $offset = (4 * 31536000) | 0;
}
else {
  # otherwise return seconds since 1972, there were 17 leap years between
  # 1900 and 1972
  $offset =  (70 * 31536000 + 17 * 86400) | 0;
}

$time - $offset;
}

sub inet_daytime
{
my $s = _socket('daytime',13,@_) || return undef;
my $buf = '';

defined($s->recv($buf, 1024)) ? $buf
                     : undef;
}

1;

__END__

=head1 NAME

Net::Time - time and daytime network client interface

=head1 SYNOPSIS

   use Net::Time qw(inet_time inet_daytime);

   print inet_time();          # use default host from Net::Config
   print inet_time('localhost');
   print inet_time('localhost', 'tcp');

   print inet_daytime();       # use default host from Net::Config
   print inet_daytime('localhost');
   print inet_daytime('localhost', 'tcp');

=head1 DESCRIPTION

C<Net::Time> provides subroutines that obtain the time on a remote machine.

=over 4

=item inet_time ( [HOST [, PROTOCOL [, TIMEOUT]]])

Obtain the time on C<HOST>, or some default host if C<HOST> is not given
or not defined, using the protocol as defined in RFC868. The optional
argument C<PROTOCOL> should define the protocol to use, either C<tcp> or
C<udp>. The result will be a time value in the same units as returned
by time() or I<undef> upon failure.

=item inet_daytime ( [HOST [, PROTOCOL [, TIMEOUT]]])

Obtain the time on C<HOST>, or some default host if C<HOST> is not given
or not defined, using the protocol as defined in RFC867. The optional
argument C<PROTOCOL> should define the protocol to use, either C<tcp> or
C<udp>. The result will be an ASCII string or I<undef> upon failure.

=back

=head1 AUTHOR

Graham Barr <gbarr@pobox.com>

=head1 COPYRIGHT

Copyright (c) 1995-2004 Graham Barr. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

=cut