1 |
root |
1.1 |
=head1 NAME |
2 |
|
|
|
3 |
|
|
EV - perl interface to libevent, monkey.org/~provos/libevent/ |
4 |
|
|
|
5 |
|
|
=head1 SYNOPSIS |
6 |
|
|
|
7 |
root |
1.11 |
use EV; |
8 |
|
|
|
9 |
|
|
# TIMER |
10 |
|
|
|
11 |
|
|
my $w = EV::timer 2, 0, sub { |
12 |
|
|
warn "is called after 2s"; |
13 |
|
|
}; |
14 |
|
|
|
15 |
|
|
my $w = EV::timer 2, 1, sub { |
16 |
|
|
warn "is called roughly every 2s (repeat = 1)"; |
17 |
|
|
}; |
18 |
|
|
|
19 |
|
|
undef $w; # destroy event watcher again |
20 |
|
|
|
21 |
|
|
my $w = EV::timer_abs 0, 60, sub { |
22 |
|
|
warn "is called every minute, on the minute, exactly"; |
23 |
|
|
}; |
24 |
|
|
|
25 |
|
|
# IO |
26 |
|
|
|
27 |
|
|
my $w = EV::io \*STDIN, EV::READ | EV::PERSIST, sub { |
28 |
|
|
my ($w, $events) = @_; # all callbacks get the watcher object and event mask |
29 |
|
|
if ($events & EV::TIMEOUT) { |
30 |
|
|
warn "nothing received on stdin for 10 seconds, retrying"; |
31 |
|
|
} else { |
32 |
|
|
warn "stdin is readable, you entered: ", <STDIN>; |
33 |
|
|
} |
34 |
|
|
}; |
35 |
|
|
$w->timeout (10); |
36 |
|
|
|
37 |
|
|
my $w = EV::timed_io \*STDIN, EV::READ, 30, sub { |
38 |
|
|
my ($w, $events) = @_; |
39 |
|
|
if ($_[1] & EV::TIMEOUT) { |
40 |
|
|
warn "nothing entered within 30 seconds, bye bye.\n"; |
41 |
|
|
$w->stop; |
42 |
|
|
} else { |
43 |
|
|
my $line = <STDIN>; |
44 |
|
|
warn "you entered something, you again have 30 seconds.\n"; |
45 |
|
|
} |
46 |
|
|
}; |
47 |
|
|
|
48 |
|
|
# SIGNALS |
49 |
|
|
|
50 |
|
|
my $w = EV::signal 'QUIT', sub { |
51 |
|
|
warn "sigquit received\n"; |
52 |
|
|
}; |
53 |
|
|
|
54 |
|
|
my $w = EV::signal 3, sub { |
55 |
|
|
warn "sigquit received (this is GNU/Linux, right?)\n"; |
56 |
|
|
}; |
57 |
|
|
|
58 |
|
|
# MAINLOOP |
59 |
|
|
EV::dispatch; # loop as long as watchers are active |
60 |
|
|
EV::loop; # the same thing |
61 |
|
|
EV::loop EV::LOOP_ONCE; # block until some events could be handles |
62 |
|
|
EV::loop EV::LOOP_NONBLOCK; # check and handle some events, but do not wait |
63 |
root |
1.2 |
|
64 |
root |
1.1 |
=head1 DESCRIPTION |
65 |
|
|
|
66 |
|
|
This module provides an interface to libevent |
67 |
root |
1.6 |
(L<http://monkey.org/~provos/libevent/>). You probably should acquaint |
68 |
|
|
yourself with its documentation and source code to be able to use this |
69 |
|
|
module fully. |
70 |
|
|
|
71 |
|
|
Please note thta this module disables the libevent EPOLL method by |
72 |
|
|
default, see BUGS, below, if you need to enable it. |
73 |
root |
1.1 |
|
74 |
|
|
=cut |
75 |
|
|
|
76 |
|
|
package EV; |
77 |
|
|
|
78 |
|
|
use strict; |
79 |
|
|
|
80 |
|
|
BEGIN { |
81 |
root |
1.12 |
our $VERSION = '0.03'; |
82 |
root |
1.1 |
use XSLoader; |
83 |
|
|
XSLoader::load "EV", $VERSION; |
84 |
|
|
} |
85 |
|
|
|
86 |
root |
1.8 |
=head1 BASIC INTERFACE |
87 |
root |
1.1 |
|
88 |
|
|
=over 4 |
89 |
|
|
|
90 |
root |
1.2 |
=item $EV::NPRI |
91 |
|
|
|
92 |
|
|
How many priority levels are available. |
93 |
|
|
|
94 |
root |
1.8 |
=item $EV::DIED |
95 |
|
|
|
96 |
|
|
Must contain a reference to a function that is called when a callback |
97 |
|
|
throws an exception (with $@ containing thr error). The default prints an |
98 |
|
|
informative message and continues. |
99 |
|
|
|
100 |
|
|
If this callback throws an exception it will be silently ignored. |
101 |
|
|
|
102 |
root |
1.2 |
=item $time = EV::now |
103 |
|
|
|
104 |
|
|
Returns the time in (fractional) seconds since the epoch. |
105 |
|
|
|
106 |
|
|
=item $version = EV::version |
107 |
|
|
|
108 |
|
|
=item $method = EV::method |
109 |
|
|
|
110 |
|
|
Return version string and event polling method used. |
111 |
|
|
|
112 |
|
|
=item EV::loop $flags # EV::LOOP_ONCE, EV::LOOP_ONESHOT |
113 |
|
|
|
114 |
|
|
=item EV::loopexit $after |
115 |
|
|
|
116 |
|
|
Exit any active loop or dispatch after C<$after> seconds or immediately if |
117 |
|
|
C<$after> is missing or zero. |
118 |
|
|
|
119 |
|
|
=item EV::dispatch |
120 |
|
|
|
121 |
|
|
Same as C<EV::loop 0>. |
122 |
|
|
|
123 |
|
|
=item EV::event $callback |
124 |
|
|
|
125 |
|
|
Creates a new event watcher waiting for nothing, calling the given callback. |
126 |
|
|
|
127 |
|
|
=item my $w = EV::io $fileno_or_fh, $eventmask, $callback |
128 |
|
|
|
129 |
|
|
=item my $w = EV::io_ns $fileno_or_fh, $eventmask, $callback |
130 |
|
|
|
131 |
|
|
As long as the returned watcher object is alive, call the C<$callback> |
132 |
|
|
when the events specified in C<$eventmask> happen. Initially, the timeout |
133 |
|
|
is disabled. |
134 |
|
|
|
135 |
root |
1.10 |
You can additionall set a timeout to occur on the watcher, but note that |
136 |
root |
1.7 |
this timeout will not be reset when you get an I/O event in the EV::PERSIST |
137 |
|
|
case, and reaching a timeout will always stop the watcher even in the |
138 |
|
|
EV::PERSIST case. |
139 |
|
|
|
140 |
|
|
If you want a timeout to occur only after a specific time of inactivity, set |
141 |
|
|
a repeating timeout and do NOT use EV::PERSIST. |
142 |
root |
1.2 |
|
143 |
|
|
Eventmask can be one or more of these constants ORed together: |
144 |
|
|
|
145 |
|
|
EV::READ wait until read() wouldn't block anymore |
146 |
|
|
EV::WRITE wait until write() wouldn't block anymore |
147 |
root |
1.7 |
EV::PERSIST stay active after a (non-timeout) event occured |
148 |
|
|
|
149 |
|
|
The C<io_ns> variant doesn't add/start the newly created watcher. |
150 |
root |
1.2 |
|
151 |
root |
1.10 |
=item my $w = EV::timed_io $fileno_or_fh, $eventmask, $timeout, $callback |
152 |
|
|
|
153 |
|
|
=item my $w = EV::timed_io_ns $fileno_or_fh, $eventmask, $timeout, $callback |
154 |
|
|
|
155 |
|
|
Same as C<io> and C<io_ns>, but also specifies a timeout (as if there was |
156 |
|
|
a call to C<< $w->timeout ($timout, 1) >>. The persist flag is not allowed |
157 |
|
|
and will automatically be cleared. The watcher will be restarted after each event. |
158 |
|
|
|
159 |
|
|
If the timeout is zero or undef, no timeout will be set, and a normal |
160 |
|
|
watcher (with the persist flag set!) will be created. |
161 |
|
|
|
162 |
|
|
This has the effect of timing out after the specified period of inactivity |
163 |
|
|
has happened. |
164 |
|
|
|
165 |
|
|
Due to the design of libevent, this is also relatively inefficient, having |
166 |
|
|
one or two io watchers and a separate timeout watcher that you reset on |
167 |
|
|
activity (by calling its C<start> method) is usually more efficient. |
168 |
|
|
|
169 |
root |
1.2 |
=item my $w = EV::timer $after, $repeat, $callback |
170 |
|
|
|
171 |
|
|
=item my $w = EV::timer_ns $after, $repeat, $callback |
172 |
|
|
|
173 |
|
|
Calls the callback after C<$after> seconds. If C<$repeat> is true, the |
174 |
|
|
timer will be restarted after the callback returns. This means that the |
175 |
|
|
callback would be called roughly every C<$after> seconds, prolonged by the |
176 |
|
|
time the callback takes. |
177 |
|
|
|
178 |
|
|
The C<timer_ns> variant doesn't add/start the newly created watcher. |
179 |
|
|
|
180 |
|
|
=item my $w = EV::timer_abs $at, $interval, $callback |
181 |
|
|
|
182 |
|
|
=item my $w = EV::timer_abs_ns $at, $interval, $callback |
183 |
|
|
|
184 |
|
|
Similar to EV::timer, but the time is given as an absolute point in time |
185 |
|
|
(C<$at>), plus an optional C<$interval>. |
186 |
|
|
|
187 |
|
|
If the C<$interval> is zero, then the callback will be called at the time |
188 |
|
|
C<$at> if that is in the future, or as soon as possible if its in the |
189 |
|
|
past. It will not automatically repeat. |
190 |
|
|
|
191 |
|
|
If the C<$interval> is nonzero, then the watcher will always be scheduled |
192 |
|
|
to time out at the next C<$at + integer * $interval> time. |
193 |
|
|
|
194 |
|
|
This can be used to schedule a callback to run at very regular intervals, |
195 |
|
|
as long as the processing time is less then the interval (otherwise |
196 |
|
|
obviously events will be skipped). |
197 |
|
|
|
198 |
root |
1.7 |
Another way to think about it (for the mathematically inclined) is that |
199 |
|
|
C<timer_abs> will try to tun the callback at the next possible time where |
200 |
|
|
C<$time = $at (mod $interval)>, regardless of any time jumps. |
201 |
|
|
|
202 |
root |
1.2 |
The C<timer_abs_ns> variant doesn't add/start the newly created watcher. |
203 |
|
|
|
204 |
root |
1.11 |
=item my $w = EV::signal $signal, $callback |
205 |
|
|
|
206 |
|
|
=item my $w = EV::signal_ns $signal, $callback |
207 |
|
|
|
208 |
|
|
Call the callback when $signal is received (the signal can be specified |
209 |
|
|
by number or by name, just as with kill or %SIG). Signal watchers are |
210 |
|
|
persistent no natter what. |
211 |
root |
1.2 |
|
212 |
root |
1.11 |
EV will grab the signal for the process (the kernel only allows one |
213 |
|
|
component to receive signals) when you start a signal watcher, and |
214 |
|
|
removes it again when you stop it. Pelr does the same when you add/remove |
215 |
|
|
callbacks to %SIG, so watch out. |
216 |
root |
1.2 |
|
217 |
root |
1.11 |
Unfortunately, only one handler can be registered per signal. Screw |
218 |
|
|
libevent. |
219 |
root |
1.2 |
|
220 |
|
|
The C<signal_ns> variant doesn't add/start the newly created watcher. |
221 |
|
|
|
222 |
root |
1.1 |
=back |
223 |
|
|
|
224 |
root |
1.2 |
=head1 THE EV::Event CLASS |
225 |
|
|
|
226 |
|
|
All EV functions creating an event watcher (designated by C<my $w => |
227 |
|
|
above) support the following methods on the returned watcher object: |
228 |
|
|
|
229 |
|
|
=over 4 |
230 |
|
|
|
231 |
|
|
=item $w->add ($timeout) |
232 |
|
|
|
233 |
|
|
Stops and (re-)starts the event watcher, setting the optional timeout to |
234 |
|
|
the given value, or clearing the timeout if none is given. |
235 |
|
|
|
236 |
|
|
=item $w->start |
237 |
|
|
|
238 |
|
|
Stops and (re-)starts the event watcher without touching the timeout. |
239 |
|
|
|
240 |
|
|
=item $w->del |
241 |
|
|
|
242 |
|
|
=item $w->stop |
243 |
root |
1.1 |
|
244 |
root |
1.2 |
Stop the event watcher if it was started. |
245 |
root |
1.1 |
|
246 |
root |
1.2 |
=item $current_callback = $w->cb |
247 |
root |
1.1 |
|
248 |
root |
1.2 |
=item $old_callback = $w->cb ($new_callback) |
249 |
|
|
|
250 |
|
|
Return the previously set callback and optionally set a new one. |
251 |
|
|
|
252 |
|
|
=item $current_fh = $w->fh |
253 |
|
|
|
254 |
|
|
=item $old_fh = $w->fh ($new_fh) |
255 |
|
|
|
256 |
root |
1.10 |
Returns the previously set filehandle and optionally set a new one (also |
257 |
|
|
clears the EV::SIGNAL flag when setting a filehandle). |
258 |
|
|
|
259 |
|
|
=item $current_signal = $w->signal |
260 |
|
|
|
261 |
|
|
=item $old_signal = $w->signal ($new_signal) |
262 |
|
|
|
263 |
|
|
Returns the previously set signal number and optionally set a new one (also sets |
264 |
|
|
the EV::SIGNAL flag when setting a signal). |
265 |
root |
1.2 |
|
266 |
|
|
=item $current_eventmask = $w->events |
267 |
|
|
|
268 |
|
|
=item $old_eventmask = $w->events ($new_eventmask) |
269 |
|
|
|
270 |
|
|
Returns the previously set event mask and optionally set a new one. |
271 |
|
|
|
272 |
|
|
=item $w->timeout ($after, $repeat) |
273 |
|
|
|
274 |
|
|
Resets the timeout (see C<EV::timer> for details). |
275 |
|
|
|
276 |
|
|
=item $w->timeout_abs ($at, $interval) |
277 |
|
|
|
278 |
|
|
Resets the timeout (see C<EV::timer_abs> for details). |
279 |
|
|
|
280 |
|
|
=item $w->priority_set ($priority) |
281 |
|
|
|
282 |
|
|
Set the priority of the watcher to C<$priority> (0 <= $priority < $EV::NPRI). |
283 |
root |
1.1 |
|
284 |
|
|
=back |
285 |
|
|
|
286 |
root |
1.13 |
=head1 THREADS |
287 |
|
|
|
288 |
|
|
Threads are not supported by this in any way. Perl pseudo-threads is evil |
289 |
|
|
and must die. |
290 |
|
|
|
291 |
root |
1.1 |
=head1 BUGS |
292 |
|
|
|
293 |
root |
1.2 |
Lots. Libevent itself isn't well tested and rather buggy, and this module |
294 |
|
|
is quite new at the moment. |
295 |
|
|
|
296 |
root |
1.7 |
Please note that the epoll method is not, in general, reliable in programs |
297 |
|
|
that use fork (even if no libveent calls are being made in the forked |
298 |
|
|
process). If your program behaves erratically, try setting the environment |
299 |
|
|
variable C<EVENT_NOEPOLL> first when running the program. |
300 |
|
|
|
301 |
|
|
In general, if you fork, then you can only use the EV module in one of the |
302 |
|
|
children. |
303 |
root |
1.6 |
|
304 |
root |
1.1 |
=cut |
305 |
|
|
|
306 |
root |
1.8 |
our $DIED = sub { |
307 |
|
|
warn "EV: error in callback (ignoring): $@"; |
308 |
|
|
}; |
309 |
|
|
|
310 |
root |
1.14 |
init; |
311 |
root |
1.1 |
|
312 |
root |
1.4 |
push @AnyEvent::REGISTRY, [EV => "EV::AnyEvent"]; |
313 |
|
|
|
314 |
root |
1.1 |
1; |
315 |
|
|
|
316 |
root |
1.3 |
=head1 SEE ALSO |
317 |
|
|
|
318 |
|
|
L<EV::DNS>, L<event(3)>, L<event.h>, L<evdns.h>. |
319 |
root |
1.5 |
L<EV::AnyEvent>. |
320 |
root |
1.3 |
|
321 |
root |
1.1 |
=head1 AUTHOR |
322 |
|
|
|
323 |
|
|
Marc Lehmann <schmorp@schmorp.de> |
324 |
|
|
http://home.schmorp.de/ |
325 |
|
|
|
326 |
|
|
=cut |
327 |
|
|
|