Coro/Event/Event.pm

=head1 NAME

Coro::Event - do events the coro-way

=head1 SYNOPSIS

 use Coro;
 use Coro::Event;

 sub keyboard : Coro {
    my $w = Coro::Event->io(fd => \*STDIN, poll => 'r');
    while() {
       print "cmd> ";
       my $ev = $w->next; my $cmd = <STDIN>;
       unloop unless $cmd ne "";
       print "data> ";
       my $ev = $w->next; my $data = <STDIN>;
    }
 }

 loop;

=head1 DESCRIPTION

This module enables you to create programs using the powerful Event model
(and module), while retaining the linear style known from simple or
threaded programs.

This module provides a method and a function for every watcher type
(I<flavour>) (see L<Event>). The only difference between these and the
watcher constructors from Event is that you do not specify a callback
function - it will be managed by this module.

Your application should just create all necessary coroutines and then call
Coro::Event::loop.

Please note that even programs or modules (such as
L<Coro::Handle|Coro::Handle>) that use "traditional"
event-based/continuation style will run more efficient with this module
then when using only Event.

=over 4

=cut

package Coro::Event;

BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }

use Carp;
no warnings;

use Coro;
use Coro::Timer;
use Event qw(loop unloop); # we are re-exporting this, cooool!

use XSLoader;

use base Exporter::;

our @EXPORT = qw(loop unloop sweep);

BEGIN {
   our $VERSION = 1.9;

   local $^W = 0; # avoid redefine warning for Coro::ready;
   XSLoader::load __PACKAGE__, $VERSION;
}

=item $w = Coro::Event->flavour(args...)

Create and return a watcher of the given type.

Examples:

  my $reader = Coro::Event->io(fd => $filehandle, poll => 'r');
  $reader->next;

=cut

=item $w->next

Return the next event of the event queue of the watcher.

=cut

=item do_flavour(args...)

Create a watcher of the given type and immediately call it's next
method. This is less efficient then calling the constructor once and the
next method often, but it does save typing sometimes.

=cut

for my $flavour (qw(idle var timer io signal)) {
   push @EXPORT, "do_$flavour";
   my $new = \&{"Event::$flavour"};
   my $class = "Coro::Event::$flavour";
   my $type = $flavour eq "io" ? 1 : 0;
   @{"${class}::ISA"} = (Coro::Event::, "Event::$flavour");
   my $coronew = sub {
      # how does one do method-call-by-name?
      # my $w = $class->SUPER::$flavour(@_);

      shift eq Coro::Event::
         or croak "event constructor \"Coro::Event->$flavour\" must be called as a static method";

      my $w = $new->($class,
            desc => $flavour,
            @_,
            parked => 1,
      );
      _install_std_cb($w, $type);
      bless $w, $class; # reblessing due to broken Event
   };
   *{    $flavour } = $coronew;
   *{"do_$flavour"} = sub {
      unshift @_, Coro::Event::;
      my $e = (&$coronew)->next;
      $e->cancel; # $e === $e->w
      $e;
   };
}

# double calls to avoid stack-cloning ;()
# is about 10% slower, though.
sub next($) {
   &Coro::schedule while &_next;

   $_[0]
}

sub Coro::Event::w    { $_[0] }
sub Coro::Event::prio { $_[0]{Coro::Event}[3] }
sub Coro::Event::hits { $_[0]{Coro::Event}[4] }
sub Coro::Event::got  { $_[0]{Coro::Event}[5] }

=item sweep

Similar to Event::one_event and Event::sweep: The idle task is called once
(this has the effect of jumping back into the Event loop once to serve new
events).

The reason this function exists is that you sometimes want to serve events
while doing other work. Calling C<Coro::cede> does not work because
C<cede> implies that the current coroutine is runnable and does not call
into the Event dispatcher.

=cut

sub sweep {
   Event::one_event(0); # for now
}

=item $result = loop([$timeout])

This is the version of C<loop> you should use instead of C<Event::loop>
when using this module - it will ensure correct scheduling in the presence
of events.

=item unloop([$result])

Same as Event::unloop (provided here for your convinience only).

=cut

$Coro::idle = \&Event::one_event; # inefficient

1;

=back

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

Revision:	1.41
Committed:	Fri Dec 1 02:17:37 2006 UTC (17 years, 7 months ago) by root
Branch:	MAIN
Changes since 1.40:	+4 -2 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			Coro::Event - do events the coro-way
4
5			=head1 SYNOPSIS
6
7			use Coro;
8			use Coro::Event;
9
10			sub keyboard : Coro {
11	pcg	1.21	my $w = Coro::Event->io(fd => \*STDIN, poll => 'r');
12	root	1.1	while() {
13			print "cmd> ";
14			my $ev = $w->next; my $cmd = <STDIN>;
15			unloop unless $cmd ne "";
16			print "data> ";
17			my $ev = $w->next; my $data = <STDIN>;
18			}
19			}
20
21	root	1.8	loop;
22	root	1.1
23			=head1 DESCRIPTION
24
25			This module enables you to create programs using the powerful Event model
26			(and module), while retaining the linear style known from simple or
27			threaded programs.
28
29			This module provides a method and a function for every watcher type
30			(I<flavour>) (see L<Event>). The only difference between these and the
31			watcher constructors from Event is that you do not specify a callback
32			function - it will be managed by this module.
33
34			Your application should just create all necessary coroutines and then call
35	root	1.12	Coro::Event::loop.
36	root	1.1
37	root	1.37	Please note that even programs or modules (such as
38			L<Coro::Handle\|Coro::Handle>) that use "traditional"
39			event-based/continuation style will run more efficient with this module
40			then when using only Event.
41
42	root	1.1	=over 4
43
44			=cut
45
46			package Coro::Event;
47
48	pcg	1.18	BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
49	root	1.1
50			use Carp;
51	root	1.30	no warnings;
52	root	1.1
53			use Coro;
54	root	1.40	use Coro::Timer;
55	root	1.8	use Event qw(loop unloop); # we are re-exporting this, cooool!
56	root	1.1
57	root	1.30	use XSLoader;
58	root	1.1
59	root	1.30	use base Exporter::;
60
61	root	1.41	our @EXPORT = qw(loop unloop sweep);
62	root	1.1
63	root	1.2	BEGIN {
64	root	1.35	our $VERSION = 1.9;
65	root	1.2
66	root	1.13	local $^W = 0; # avoid redefine warning for Coro::ready;
67	root	1.30	XSLoader::load __PACKAGE__, $VERSION;
68	root	1.2	}
69	root	1.1
70			=item $w = Coro::Event->flavour(args...)
71
72			Create and return a watcher of the given type.
73
74			Examples:
75
76			my $reader = Coro::Event->io(fd => $filehandle, poll => 'r');
77			$reader->next;
78
79			=cut
80
81			=item $w->next
82
83			Return the next event of the event queue of the watcher.
84
85			=cut
86
87			=item do_flavour(args...)
88
89			Create a watcher of the given type and immediately call it's next
90			method. This is less efficient then calling the constructor once and the
91			next method often, but it does save typing sometimes.
92
93			=cut
94
95			for my $flavour (qw(idle var timer io signal)) {
96			push @EXPORT, "do_$flavour";
97			my $new = \&{"Event::$flavour"};
98			my $class = "Coro::Event::$flavour";
99	root	1.2	my $type = $flavour eq "io" ? 1 : 0;
100	root	1.1	@{"${class}::ISA"} = (Coro::Event::, "Event::$flavour");
101			my $coronew = sub {
102			# how does one do method-call-by-name?
103			# my $w = $class->SUPER::$flavour(@_);
104
105	root	1.10	shift eq Coro::Event::
106	root	1.1	or croak "event constructor \"Coro::Event->$flavour\" must be called as a static method";
107
108	root	1.10	my $w = $new->($class,
109	root	1.1	desc => $flavour,
110			@_,
111	root	1.2	parked => 1,
112	root	1.1	);
113	root	1.2	_install_std_cb($w, $type);
114	root	1.1	bless $w, $class; # reblessing due to broken Event
115			};
116			*{ $flavour } = $coronew;
117			*{"do_$flavour"} = sub {
118			unshift @_, Coro::Event::;
119			my $e = (&$coronew)->next;
120	pcg	1.20	$e->cancel; # $e === $e->w
121	root	1.1	$e;
122			};
123			}
124
125	root	1.2	# double calls to avoid stack-cloning ;()
126	root	1.3	# is about 10% slower, though.
127	root	1.2	sub next($) {
128	root	1.41	&Coro::schedule while &_next;
129
130			$_[0]
131	root	1.1	}
132	root	1.2
133	root	1.4	sub Coro::Event::w { $_[0] }
134	root	1.5	sub Coro::Event::prio { $_[0]{Coro::Event}[3] }
135			sub Coro::Event::hits { $_[0]{Coro::Event}[4] }
136			sub Coro::Event::got { $_[0]{Coro::Event}[5] }
137	root	1.1
138			=item sweep
139
140			Similar to Event::one_event and Event::sweep: The idle task is called once
141			(this has the effect of jumping back into the Event loop once to serve new
142			events).
143
144			The reason this function exists is that you sometimes want to serve events
145			while doing other work. Calling C<Coro::cede> does not work because
146			C<cede> implies that the current coroutine is runnable and does not call
147			into the Event dispatcher.
148
149			=cut
150
151			sub sweep {
152	root	1.7	Event::one_event(0); # for now
153	root	1.1	}
154
155			=item $result = loop([$timeout])
156
157			This is the version of C<loop> you should use instead of C<Event::loop>
158			when using this module - it will ensure correct scheduling in the presence
159			of events.
160
161			=item unloop([$result])
162
163			Same as Event::unloop (provided here for your convinience only).
164
165			=cut
166
167	root	1.40	$Coro::idle = \&Event::one_event; # inefficient
168	root	1.9
169	root	1.1	1;
170
171	root	1.36	=back
172
173	root	1.1	=head1 AUTHOR
174
175	root	1.27	Marc Lehmann <schmorp@schmorp.de>
176	root	1.25	http://home.schmorp.de/
177	root	1.1
178			=cut
179