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Revision: 1.43
Committed: Fri Dec 1 19:41:06 2006 UTC (17 years, 6 months ago) by root
Branch: MAIN
Changes since 1.42: +10 -7 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
126 _install_std_cb $w, $type;
127
128 # reblessing due to Event being broken
129 bless $w, $class
130 };
131 *{ $flavour } = $coronew;
132 *{"do_$flavour"} = sub {
133 unshift @_, Coro::Event::;
134 my $e = &$coronew->next;
135 $e->cancel; # $e === $e->w
136 $e
137 };
138 }
139
140 # do schedule in perl to avoid forcign a stack allocation.
141 # this is about 10% slower, though.
142 sub next($) {
143 &Coro::schedule while &_next;
144
145 $_[0]
146 }
147
148 sub Coro::Event::w { $_[0] }
149 sub Coro::Event::prio { $_[0]{Coro::Event}[3] }
150 sub Coro::Event::hits { $_[0]{Coro::Event}[4] }
151 sub Coro::Event::got { $_[0]{Coro::Event}[5] }
152
153 =item sweep
154
155 Similar to Event::one_event and Event::sweep: The idle task is called once
156 (this has the effect of jumping back into the Event loop once to serve new
157 events).
158
159 The reason this function exists is that you sometimes want to serve events
160 while doing other work. Calling C<Coro::cede> does not work because
161 C<cede> implies that the current coroutine is runnable and does not call
162 into the Event dispatcher.
163
164 =cut
165
166 sub sweep {
167 Event::one_event 0; # for now
168 }
169
170 =item $result = loop([$timeout])
171
172 This is the version of C<loop> you should use instead of C<Event::loop>
173 when using this module - it will ensure correct scheduling in the presence
174 of events.
175
176 =item unloop([$result])
177
178 Same as Event::unloop (provided here for your convinience only).
179
180 =cut
181
182 $Coro::idle = \&Event::one_event; # inefficient
183
184 1;
185
186 =back
187
188 =head1 AUTHOR
189
190 Marc Lehmann <schmorp@schmorp.de>
191 http://home.schmorp.de/
192
193 =cut
194