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Revision: 1.42
Committed: Fri Dec 1 02:24:46 2006 UTC (17 years, 6 months ago) by root
Branch: MAIN
Changes since 1.41: +16 -4 lines
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# Content
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 my $w = Coro::Event->io(fd => \*STDIN, poll => 'r');
12 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 loop;
22
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 Coro::Event::loop.
36
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 =head1 WARNING
43
44 Please note that Event does not support coroutines or threads. That
45 means that you B<MUST NOT> block in an event callback. Again: In Event
46 callbacks, you I<must never ever> call a Coroutine fucntion that blocks
47 the current coroutine.
48
49 While this seems to work superficially, it will eventually cause memory
50 corruption.
51
52 =head1 FUNCTIONS
53
54 =over 4
55
56 =cut
57
58 package Coro::Event;
59
60 no warnings;
61
62 use Carp;
63 no warnings;
64
65 use Coro;
66 use Coro::Timer;
67 use Event qw(loop unloop); # we are re-exporting this, cooool!
68
69 use XSLoader;
70
71 use base Exporter::;
72
73 our @EXPORT = qw(loop unloop sweep);
74
75 BEGIN {
76 our $VERSION = 1.9;
77
78 local $^W = 0; # avoid redefine warning for Coro::ready;
79 XSLoader::load __PACKAGE__, $VERSION;
80 }
81
82 =item $w = Coro::Event->flavour (args...)
83
84 Create and return a watcher of the given type.
85
86 Examples:
87
88 my $reader = Coro::Event->io(fd => $filehandle, poll => 'r');
89 $reader->next;
90
91 =cut
92
93 =item $w->next
94
95 Return the next event of the event queue of the watcher.
96
97 =cut
98
99 =item do_flavour args...
100
101 Create a watcher of the given type and immediately call it's next
102 method. This is less efficient then calling the constructor once and the
103 next method often, but it does save typing sometimes.
104
105 =cut
106
107 for my $flavour (qw(idle var timer io signal)) {
108 push @EXPORT, "do_$flavour";
109 my $new = \&{"Event::$flavour"};
110 my $class = "Coro::Event::$flavour";
111 my $type = $flavour eq "io" ? 1 : 0;
112 @{"${class}::ISA"} = (Coro::Event::, "Event::$flavour");
113 my $coronew = sub {
114 # how does one do method-call-by-name?
115 # my $w = $class->SUPER::$flavour(@_);
116
117 shift eq Coro::Event::
118 or croak "event constructor \"Coro::Event->$flavour\" must be called as a static method";
119
120 my $w = $new->($class,
121 desc => $flavour,
122 @_,
123 parked => 1,
124 );
125 _install_std_cb($w, $type);
126 bless $w, $class; # reblessing due to broken Event
127 };
128 *{ $flavour } = $coronew;
129 *{"do_$flavour"} = sub {
130 unshift @_, Coro::Event::;
131 my $e = (&$coronew)->next;
132 $e->cancel; # $e === $e->w
133 $e;
134 };
135 }
136
137 # double calls to avoid stack-cloning ;()
138 # is about 10% slower, though.
139 sub next($) {
140 &Coro::schedule while &_next;
141
142 $_[0]
143 }
144
145 sub Coro::Event::w { $_[0] }
146 sub Coro::Event::prio { $_[0]{Coro::Event}[3] }
147 sub Coro::Event::hits { $_[0]{Coro::Event}[4] }
148 sub Coro::Event::got { $_[0]{Coro::Event}[5] }
149
150 =item sweep
151
152 Similar to Event::one_event and Event::sweep: The idle task is called once
153 (this has the effect of jumping back into the Event loop once to serve new
154 events).
155
156 The reason this function exists is that you sometimes want to serve events
157 while doing other work. Calling C<Coro::cede> does not work because
158 C<cede> implies that the current coroutine is runnable and does not call
159 into the Event dispatcher.
160
161 =cut
162
163 sub sweep {
164 Event::one_event 0; # for now
165 }
166
167 =item $result = loop([$timeout])
168
169 This is the version of C<loop> you should use instead of C<Event::loop>
170 when using this module - it will ensure correct scheduling in the presence
171 of events.
172
173 =item unloop([$result])
174
175 Same as Event::unloop (provided here for your convinience only).
176
177 =cut
178
179 $Coro::idle = \&Event::one_event; # inefficient
180
181 1;
182
183 =back
184
185 =head1 AUTHOR
186
187 Marc Lehmann <schmorp@schmorp.de>
188 http://home.schmorp.de/
189
190 =cut
191