… | |
… | |
6 | |
6 | |
7 | =head1 SYNOPSIS |
7 | =head1 SYNOPSIS |
8 | |
8 | |
9 | use AnyEvent; |
9 | use AnyEvent; |
10 | |
10 | |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... }); |
12 | ... |
|
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13 | }); |
|
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14 | |
12 | |
15 | my $w = AnyEvent->timer (after => $seconds, cb => sub { |
13 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
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14 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
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15 | |
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16 | print AnyEvent->now; # prints current event loop time |
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17 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
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18 | |
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19 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
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20 | |
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21 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
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22 | my ($pid, $status) = @_; |
16 | ... |
23 | ... |
17 | }); |
24 | }); |
18 | |
25 | |
19 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
26 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
20 | $w->send; # wake up current and all future recv's |
27 | $w->send; # wake up current and all future recv's |
21 | $w->recv; # enters "main loop" till $condvar gets ->send |
28 | $w->recv; # enters "main loop" till $condvar gets ->send |
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29 | # use a condvar in callback mode: |
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30 | $w->cb (sub { $_[0]->recv }); |
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31 | |
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32 | =head1 INTRODUCTION/TUTORIAL |
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33 | |
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34 | This manpage is mainly a reference manual. If you are interested |
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35 | in a tutorial or some gentle introduction, have a look at the |
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36 | L<AnyEvent::Intro> manpage. |
22 | |
37 | |
23 | =head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) |
38 | =head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) |
24 | |
39 | |
25 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
40 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
26 | nowadays. So what is different about AnyEvent? |
41 | nowadays. So what is different about AnyEvent? |
27 | |
42 | |
28 | Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of |
43 | Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of |
29 | policy> and AnyEvent is I<small and efficient>. |
44 | policy> and AnyEvent is I<small and efficient>. |
30 | |
45 | |
31 | First and foremost, I<AnyEvent is not an event model> itself, it only |
46 | First and foremost, I<AnyEvent is not an event model> itself, it only |
32 | interfaces to whatever event model the main program happens to use in a |
47 | interfaces to whatever event model the main program happens to use, in a |
33 | pragmatic way. For event models and certain classes of immortals alike, |
48 | pragmatic way. For event models and certain classes of immortals alike, |
34 | the statement "there can only be one" is a bitter reality: In general, |
49 | the statement "there can only be one" is a bitter reality: In general, |
35 | only one event loop can be active at the same time in a process. AnyEvent |
50 | only one event loop can be active at the same time in a process. AnyEvent |
36 | helps hiding the differences between those event loops. |
51 | cannot change this, but it can hide the differences between those event |
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52 | loops. |
37 | |
53 | |
38 | The goal of AnyEvent is to offer module authors the ability to do event |
54 | The goal of AnyEvent is to offer module authors the ability to do event |
39 | programming (waiting for I/O or timer events) without subscribing to a |
55 | programming (waiting for I/O or timer events) without subscribing to a |
40 | religion, a way of living, and most importantly: without forcing your |
56 | religion, a way of living, and most importantly: without forcing your |
41 | module users into the same thing by forcing them to use the same event |
57 | module users into the same thing by forcing them to use the same event |
42 | model you use. |
58 | model you use. |
43 | |
59 | |
44 | For modules like POE or IO::Async (which is a total misnomer as it is |
60 | For modules like POE or IO::Async (which is a total misnomer as it is |
45 | actually doing all I/O I<synchronously>...), using them in your module is |
61 | actually doing all I/O I<synchronously>...), using them in your module is |
46 | like joining a cult: After you joined, you are dependent on them and you |
62 | like joining a cult: After you joined, you are dependent on them and you |
47 | cannot use anything else, as it is simply incompatible to everything that |
63 | cannot use anything else, as they are simply incompatible to everything |
48 | isn't itself. What's worse, all the potential users of your module are |
64 | that isn't them. What's worse, all the potential users of your |
49 | I<also> forced to use the same event loop you use. |
65 | module are I<also> forced to use the same event loop you use. |
50 | |
66 | |
51 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
67 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
52 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
68 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
53 | with the rest: POE + IO::Async? no go. Tk + Event? no go. Again: if |
69 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if |
54 | your module uses one of those, every user of your module has to use it, |
70 | your module uses one of those, every user of your module has to use it, |
55 | too. But if your module uses AnyEvent, it works transparently with all |
71 | too. But if your module uses AnyEvent, it works transparently with all |
56 | event models it supports (including stuff like POE and IO::Async, as long |
72 | event models it supports (including stuff like IO::Async, as long as those |
57 | as those use one of the supported event loops. It is trivial to add new |
73 | use one of the supported event loops. It is trivial to add new event loops |
58 | event loops to AnyEvent, too, so it is future-proof). |
74 | to AnyEvent, too, so it is future-proof). |
59 | |
75 | |
60 | In addition to being free of having to use I<the one and only true event |
76 | In addition to being free of having to use I<the one and only true event |
61 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
77 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
62 | modules, you get an enourmous amount of code and strict rules you have to |
78 | modules, you get an enormous amount of code and strict rules you have to |
63 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
79 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
64 | offering the functionality that is necessary, in as thin as a wrapper as |
80 | offering the functionality that is necessary, in as thin as a wrapper as |
65 | technically possible. |
81 | technically possible. |
66 | |
82 | |
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83 | Of course, AnyEvent comes with a big (and fully optional!) toolbox |
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84 | of useful functionality, such as an asynchronous DNS resolver, 100% |
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85 | non-blocking connects (even with TLS/SSL, IPv6 and on broken platforms |
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86 | such as Windows) and lots of real-world knowledge and workarounds for |
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87 | platform bugs and differences. |
|
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88 | |
67 | Of course, if you want lots of policy (this can arguably be somewhat |
89 | Now, if you I<do want> lots of policy (this can arguably be somewhat |
68 | useful) and you want to force your users to use the one and only event |
90 | useful) and you want to force your users to use the one and only event |
69 | model, you should I<not> use this module. |
91 | model, you should I<not> use this module. |
70 | |
92 | |
71 | =head1 DESCRIPTION |
93 | =head1 DESCRIPTION |
72 | |
94 | |
… | |
… | |
102 | starts using it, all bets are off. Maybe you should tell their authors to |
124 | starts using it, all bets are off. Maybe you should tell their authors to |
103 | use AnyEvent so their modules work together with others seamlessly... |
125 | use AnyEvent so their modules work together with others seamlessly... |
104 | |
126 | |
105 | The pure-perl implementation of AnyEvent is called |
127 | The pure-perl implementation of AnyEvent is called |
106 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
128 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
107 | explicitly. |
129 | explicitly and enjoy the high availability of that event loop :) |
108 | |
130 | |
109 | =head1 WATCHERS |
131 | =head1 WATCHERS |
110 | |
132 | |
111 | AnyEvent has the central concept of a I<watcher>, which is an object that |
133 | AnyEvent has the central concept of a I<watcher>, which is an object that |
112 | stores relevant data for each kind of event you are waiting for, such as |
134 | stores relevant data for each kind of event you are waiting for, such as |
113 | the callback to call, the filehandle to watch, etc. |
135 | the callback to call, the file handle to watch, etc. |
114 | |
136 | |
115 | These watchers are normal Perl objects with normal Perl lifetime. After |
137 | These watchers are normal Perl objects with normal Perl lifetime. After |
116 | creating a watcher it will immediately "watch" for events and invoke the |
138 | creating a watcher it will immediately "watch" for events and invoke the |
117 | callback when the event occurs (of course, only when the event model |
139 | callback when the event occurs (of course, only when the event model |
118 | is in control). |
140 | is in control). |
… | |
… | |
126 | Many watchers either are used with "recursion" (repeating timers for |
148 | Many watchers either are used with "recursion" (repeating timers for |
127 | example), or need to refer to their watcher object in other ways. |
149 | example), or need to refer to their watcher object in other ways. |
128 | |
150 | |
129 | An any way to achieve that is this pattern: |
151 | An any way to achieve that is this pattern: |
130 | |
152 | |
131 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
153 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
132 | # you can use $w here, for example to undef it |
154 | # you can use $w here, for example to undef it |
133 | undef $w; |
155 | undef $w; |
134 | }); |
156 | }); |
135 | |
157 | |
136 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
158 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
137 | my variables are only visible after the statement in which they are |
159 | my variables are only visible after the statement in which they are |
138 | declared. |
160 | declared. |
139 | |
161 | |
140 | =head2 I/O WATCHERS |
162 | =head2 I/O WATCHERS |
141 | |
163 | |
142 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
164 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
143 | with the following mandatory key-value pairs as arguments: |
165 | with the following mandatory key-value pairs as arguments: |
144 | |
166 | |
145 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch |
167 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events |
146 | for events. C<poll> must be a string that is either C<r> or C<w>, |
168 | (AnyEvent might or might not keep a reference to this file handle). C<poll> |
147 | which creates a watcher waiting for "r"eadable or "w"ritable events, |
169 | must be a string that is either C<r> or C<w>, which creates a watcher |
148 | respectively. C<cb> is the callback to invoke each time the file handle |
170 | waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the |
149 | becomes ready. |
171 | callback to invoke each time the file handle becomes ready. |
150 | |
172 | |
151 | Although the callback might get passed parameters, their value and |
173 | Although the callback might get passed parameters, their value and |
152 | presence is undefined and you cannot rely on them. Portable AnyEvent |
174 | presence is undefined and you cannot rely on them. Portable AnyEvent |
153 | callbacks cannot use arguments passed to I/O watcher callbacks. |
175 | callbacks cannot use arguments passed to I/O watcher callbacks. |
154 | |
176 | |
… | |
… | |
158 | |
180 | |
159 | Some event loops issue spurious readyness notifications, so you should |
181 | Some event loops issue spurious readyness notifications, so you should |
160 | always use non-blocking calls when reading/writing from/to your file |
182 | always use non-blocking calls when reading/writing from/to your file |
161 | handles. |
183 | handles. |
162 | |
184 | |
163 | Example: |
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164 | |
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165 | # wait for readability of STDIN, then read a line and disable the watcher |
185 | Example: wait for readability of STDIN, then read a line and disable the |
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186 | watcher. |
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187 | |
166 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
188 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
167 | chomp (my $input = <STDIN>); |
189 | chomp (my $input = <STDIN>); |
168 | warn "read: $input\n"; |
190 | warn "read: $input\n"; |
169 | undef $w; |
191 | undef $w; |
170 | }); |
192 | }); |
… | |
… | |
180 | |
202 | |
181 | Although the callback might get passed parameters, their value and |
203 | Although the callback might get passed parameters, their value and |
182 | presence is undefined and you cannot rely on them. Portable AnyEvent |
204 | presence is undefined and you cannot rely on them. Portable AnyEvent |
183 | callbacks cannot use arguments passed to time watcher callbacks. |
205 | callbacks cannot use arguments passed to time watcher callbacks. |
184 | |
206 | |
185 | The timer callback will be invoked at most once: if you want a repeating |
207 | The callback will normally be invoked once only. If you specify another |
186 | timer you have to create a new watcher (this is a limitation by both Tk |
208 | parameter, C<interval>, as a strictly positive number (> 0), then the |
187 | and Glib). |
209 | callback will be invoked regularly at that interval (in fractional |
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210 | seconds) after the first invocation. If C<interval> is specified with a |
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211 | false value, then it is treated as if it were missing. |
188 | |
212 | |
189 | Example: |
213 | The callback will be rescheduled before invoking the callback, but no |
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214 | attempt is done to avoid timer drift in most backends, so the interval is |
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215 | only approximate. |
190 | |
216 | |
191 | # fire an event after 7.7 seconds |
217 | Example: fire an event after 7.7 seconds. |
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218 | |
192 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
219 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
193 | warn "timeout\n"; |
220 | warn "timeout\n"; |
194 | }); |
221 | }); |
195 | |
222 | |
196 | # to cancel the timer: |
223 | # to cancel the timer: |
197 | undef $w; |
224 | undef $w; |
198 | |
225 | |
199 | Example 2: |
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200 | |
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201 | # fire an event after 0.5 seconds, then roughly every second |
226 | Example 2: fire an event after 0.5 seconds, then roughly every second. |
202 | my $w; |
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203 | |
227 | |
204 | my $cb = sub { |
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205 | # cancel the old timer while creating a new one |
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206 | $w = AnyEvent->timer (after => 1, cb => $cb); |
228 | my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { |
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229 | warn "timeout\n"; |
207 | }; |
230 | }; |
208 | |
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209 | # start the "loop" by creating the first watcher |
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210 | $w = AnyEvent->timer (after => 0.5, cb => $cb); |
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211 | |
231 | |
212 | =head3 TIMING ISSUES |
232 | =head3 TIMING ISSUES |
213 | |
233 | |
214 | There are two ways to handle timers: based on real time (relative, "fire |
234 | There are two ways to handle timers: based on real time (relative, "fire |
215 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
235 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
… | |
… | |
227 | timers. |
247 | timers. |
228 | |
248 | |
229 | AnyEvent always prefers relative timers, if available, matching the |
249 | AnyEvent always prefers relative timers, if available, matching the |
230 | AnyEvent API. |
250 | AnyEvent API. |
231 | |
251 | |
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252 | AnyEvent has two additional methods that return the "current time": |
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253 | |
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254 | =over 4 |
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255 | |
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256 | =item AnyEvent->time |
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257 | |
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258 | This returns the "current wallclock time" as a fractional number of |
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259 | seconds since the Epoch (the same thing as C<time> or C<Time::HiRes::time> |
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260 | return, and the result is guaranteed to be compatible with those). |
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261 | |
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262 | It progresses independently of any event loop processing, i.e. each call |
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263 | will check the system clock, which usually gets updated frequently. |
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264 | |
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265 | =item AnyEvent->now |
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266 | |
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267 | This also returns the "current wallclock time", but unlike C<time>, above, |
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268 | this value might change only once per event loop iteration, depending on |
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269 | the event loop (most return the same time as C<time>, above). This is the |
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270 | time that AnyEvent's timers get scheduled against. |
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271 | |
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272 | I<In almost all cases (in all cases if you don't care), this is the |
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273 | function to call when you want to know the current time.> |
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274 | |
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275 | This function is also often faster then C<< AnyEvent->time >>, and |
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276 | thus the preferred method if you want some timestamp (for example, |
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277 | L<AnyEvent::Handle> uses this to update it's activity timeouts). |
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278 | |
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279 | The rest of this section is only of relevance if you try to be very exact |
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280 | with your timing, you can skip it without bad conscience. |
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281 | |
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282 | For a practical example of when these times differ, consider L<Event::Lib> |
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283 | and L<EV> and the following set-up: |
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284 | |
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285 | The event loop is running and has just invoked one of your callback at |
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286 | time=500 (assume no other callbacks delay processing). In your callback, |
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287 | you wait a second by executing C<sleep 1> (blocking the process for a |
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288 | second) and then (at time=501) you create a relative timer that fires |
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289 | after three seconds. |
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290 | |
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291 | With L<Event::Lib>, C<< AnyEvent->time >> and C<< AnyEvent->now >> will |
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292 | both return C<501>, because that is the current time, and the timer will |
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293 | be scheduled to fire at time=504 (C<501> + C<3>). |
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294 | |
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295 | With L<EV>, C<< AnyEvent->time >> returns C<501> (as that is the current |
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296 | time), but C<< AnyEvent->now >> returns C<500>, as that is the time the |
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297 | last event processing phase started. With L<EV>, your timer gets scheduled |
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298 | to run at time=503 (C<500> + C<3>). |
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299 | |
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300 | In one sense, L<Event::Lib> is more exact, as it uses the current time |
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301 | regardless of any delays introduced by event processing. However, most |
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302 | callbacks do not expect large delays in processing, so this causes a |
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303 | higher drift (and a lot more system calls to get the current time). |
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304 | |
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305 | In another sense, L<EV> is more exact, as your timer will be scheduled at |
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306 | the same time, regardless of how long event processing actually took. |
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307 | |
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308 | In either case, if you care (and in most cases, you don't), then you |
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309 | can get whatever behaviour you want with any event loop, by taking the |
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310 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
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311 | account. |
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312 | |
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313 | =back |
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314 | |
232 | =head2 SIGNAL WATCHERS |
315 | =head2 SIGNAL WATCHERS |
233 | |
316 | |
234 | You can watch for signals using a signal watcher, C<signal> is the signal |
317 | You can watch for signals using a signal watcher, C<signal> is the signal |
235 | I<name> without any C<SIG> prefix, C<cb> is the Perl callback to |
318 | I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl |
236 | be invoked whenever a signal occurs. |
319 | callback to be invoked whenever a signal occurs. |
237 | |
320 | |
238 | Although the callback might get passed parameters, their value and |
321 | Although the callback might get passed parameters, their value and |
239 | presence is undefined and you cannot rely on them. Portable AnyEvent |
322 | presence is undefined and you cannot rely on them. Portable AnyEvent |
240 | callbacks cannot use arguments passed to signal watcher callbacks. |
323 | callbacks cannot use arguments passed to signal watcher callbacks. |
241 | |
324 | |
242 | Multiple signal occurances can be clumped together into one callback |
325 | Multiple signal occurrences can be clumped together into one callback |
243 | invocation, and callback invocation will be synchronous. synchronous means |
326 | invocation, and callback invocation will be synchronous. Synchronous means |
244 | that it might take a while until the signal gets handled by the process, |
327 | that it might take a while until the signal gets handled by the process, |
245 | but it is guarenteed not to interrupt any other callbacks. |
328 | but it is guaranteed not to interrupt any other callbacks. |
246 | |
329 | |
247 | The main advantage of using these watchers is that you can share a signal |
330 | The main advantage of using these watchers is that you can share a signal |
248 | between multiple watchers. |
331 | between multiple watchers. |
249 | |
332 | |
250 | This watcher might use C<%SIG>, so programs overwriting those signals |
333 | This watcher might use C<%SIG>, so programs overwriting those signals |
… | |
… | |
277 | AnyEvent program, you I<have> to create at least one watcher before you |
360 | AnyEvent program, you I<have> to create at least one watcher before you |
278 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
361 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
279 | |
362 | |
280 | Example: fork a process and wait for it |
363 | Example: fork a process and wait for it |
281 | |
364 | |
282 | my $done = AnyEvent->condvar; |
365 | my $done = AnyEvent->condvar; |
283 | |
366 | |
284 | my $pid = fork or exit 5; |
367 | my $pid = fork or exit 5; |
285 | |
368 | |
286 | my $w = AnyEvent->child ( |
369 | my $w = AnyEvent->child ( |
287 | pid => $pid, |
370 | pid => $pid, |
288 | cb => sub { |
371 | cb => sub { |
289 | my ($pid, $status) = @_; |
372 | my ($pid, $status) = @_; |
290 | warn "pid $pid exited with status $status"; |
373 | warn "pid $pid exited with status $status"; |
291 | $done->send; |
374 | $done->send; |
292 | }, |
375 | }, |
293 | ); |
376 | ); |
294 | |
377 | |
295 | # do something else, then wait for process exit |
378 | # do something else, then wait for process exit |
296 | $done->recv; |
379 | $done->recv; |
297 | |
380 | |
298 | =head2 CONDITION VARIABLES |
381 | =head2 CONDITION VARIABLES |
299 | |
382 | |
300 | If you are familiar with some event loops you will know that all of them |
383 | If you are familiar with some event loops you will know that all of them |
301 | require you to run some blocking "loop", "run" or similar function that |
384 | require you to run some blocking "loop", "run" or similar function that |
… | |
… | |
307 | The instrument to do that is called a "condition variable", so called |
390 | The instrument to do that is called a "condition variable", so called |
308 | because they represent a condition that must become true. |
391 | because they represent a condition that must become true. |
309 | |
392 | |
310 | Condition variables can be created by calling the C<< AnyEvent->condvar |
393 | Condition variables can be created by calling the C<< AnyEvent->condvar |
311 | >> method, usually without arguments. The only argument pair allowed is |
394 | >> method, usually without arguments. The only argument pair allowed is |
|
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395 | |
312 | C<cb>, which specifies a callback to be called when the condition variable |
396 | C<cb>, which specifies a callback to be called when the condition variable |
313 | becomes true. |
397 | becomes true, with the condition variable as the first argument (but not |
|
|
398 | the results). |
314 | |
399 | |
315 | After creation, the conditon variable is "false" until it becomes "true" |
400 | After creation, the condition variable is "false" until it becomes "true" |
316 | by calling the C<send> method. |
401 | by calling the C<send> method (or calling the condition variable as if it |
|
|
402 | were a callback, read about the caveats in the description for the C<< |
|
|
403 | ->send >> method). |
317 | |
404 | |
318 | Condition variables are similar to callbacks, except that you can |
405 | Condition variables are similar to callbacks, except that you can |
319 | optionally wait for them. They can also be called merge points - points |
406 | optionally wait for them. They can also be called merge points - points |
320 | in time where multiple outstandign events have been processed. And yet |
407 | in time where multiple outstanding events have been processed. And yet |
321 | another way to call them is transations - each condition variable can be |
408 | another way to call them is transactions - each condition variable can be |
322 | used to represent a transaction, which finishes at some point and delivers |
409 | used to represent a transaction, which finishes at some point and delivers |
323 | a result. |
410 | a result. |
324 | |
411 | |
325 | Condition variables are very useful to signal that something has finished, |
412 | Condition variables are very useful to signal that something has finished, |
326 | for example, if you write a module that does asynchronous http requests, |
413 | for example, if you write a module that does asynchronous http requests, |
… | |
… | |
332 | you can block your main program until an event occurs - for example, you |
419 | you can block your main program until an event occurs - for example, you |
333 | could C<< ->recv >> in your main program until the user clicks the Quit |
420 | could C<< ->recv >> in your main program until the user clicks the Quit |
334 | button of your app, which would C<< ->send >> the "quit" event. |
421 | button of your app, which would C<< ->send >> the "quit" event. |
335 | |
422 | |
336 | Note that condition variables recurse into the event loop - if you have |
423 | Note that condition variables recurse into the event loop - if you have |
337 | two pieces of code that call C<< ->recv >> in a round-robbin fashion, you |
424 | two pieces of code that call C<< ->recv >> in a round-robin fashion, you |
338 | lose. Therefore, condition variables are good to export to your caller, but |
425 | lose. Therefore, condition variables are good to export to your caller, but |
339 | you should avoid making a blocking wait yourself, at least in callbacks, |
426 | you should avoid making a blocking wait yourself, at least in callbacks, |
340 | as this asks for trouble. |
427 | as this asks for trouble. |
341 | |
428 | |
342 | Condition variables are represented by hash refs in perl, and the keys |
429 | Condition variables are represented by hash refs in perl, and the keys |
… | |
… | |
347 | |
434 | |
348 | There are two "sides" to a condition variable - the "producer side" which |
435 | There are two "sides" to a condition variable - the "producer side" which |
349 | eventually calls C<< -> send >>, and the "consumer side", which waits |
436 | eventually calls C<< -> send >>, and the "consumer side", which waits |
350 | for the send to occur. |
437 | for the send to occur. |
351 | |
438 | |
352 | Example: |
439 | Example: wait for a timer. |
353 | |
440 | |
354 | # wait till the result is ready |
441 | # wait till the result is ready |
355 | my $result_ready = AnyEvent->condvar; |
442 | my $result_ready = AnyEvent->condvar; |
356 | |
443 | |
357 | # do something such as adding a timer |
444 | # do something such as adding a timer |
… | |
… | |
365 | |
452 | |
366 | # this "blocks" (while handling events) till the callback |
453 | # this "blocks" (while handling events) till the callback |
367 | # calls send |
454 | # calls send |
368 | $result_ready->recv; |
455 | $result_ready->recv; |
369 | |
456 | |
|
|
457 | Example: wait for a timer, but take advantage of the fact that |
|
|
458 | condition variables are also code references. |
|
|
459 | |
|
|
460 | my $done = AnyEvent->condvar; |
|
|
461 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
|
|
462 | $done->recv; |
|
|
463 | |
|
|
464 | Example: Imagine an API that returns a condvar and doesn't support |
|
|
465 | callbacks. This is how you make a synchronous call, for example from |
|
|
466 | the main program: |
|
|
467 | |
|
|
468 | use AnyEvent::CouchDB; |
|
|
469 | |
|
|
470 | ... |
|
|
471 | |
|
|
472 | my @info = $couchdb->info->recv; |
|
|
473 | |
|
|
474 | And this is how you would just ste a callback to be called whenever the |
|
|
475 | results are available: |
|
|
476 | |
|
|
477 | $couchdb->info->cb (sub { |
|
|
478 | my @info = $_[0]->recv; |
|
|
479 | }); |
|
|
480 | |
370 | =head3 METHODS FOR PRODUCERS |
481 | =head3 METHODS FOR PRODUCERS |
371 | |
482 | |
372 | These methods should only be used by the producing side, i.e. the |
483 | These methods should only be used by the producing side, i.e. the |
373 | code/module that eventually sends the signal. Note that it is also |
484 | code/module that eventually sends the signal. Note that it is also |
374 | the producer side which creates the condvar in most cases, but it isn't |
485 | the producer side which creates the condvar in most cases, but it isn't |
… | |
… | |
385 | If a callback has been set on the condition variable, it is called |
496 | If a callback has been set on the condition variable, it is called |
386 | immediately from within send. |
497 | immediately from within send. |
387 | |
498 | |
388 | Any arguments passed to the C<send> call will be returned by all |
499 | Any arguments passed to the C<send> call will be returned by all |
389 | future C<< ->recv >> calls. |
500 | future C<< ->recv >> calls. |
|
|
501 | |
|
|
502 | Condition variables are overloaded so one can call them directly |
|
|
503 | (as a code reference). Calling them directly is the same as calling |
|
|
504 | C<send>. Note, however, that many C-based event loops do not handle |
|
|
505 | overloading, so as tempting as it may be, passing a condition variable |
|
|
506 | instead of a callback does not work. Both the pure perl and EV loops |
|
|
507 | support overloading, however, as well as all functions that use perl to |
|
|
508 | invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for |
|
|
509 | example). |
390 | |
510 | |
391 | =item $cv->croak ($error) |
511 | =item $cv->croak ($error) |
392 | |
512 | |
393 | Similar to send, but causes all call's to C<< ->recv >> to invoke |
513 | Similar to send, but causes all call's to C<< ->recv >> to invoke |
394 | C<Carp::croak> with the given error message/object/scalar. |
514 | C<Carp::croak> with the given error message/object/scalar. |
… | |
… | |
443 | doesn't execute once). |
563 | doesn't execute once). |
444 | |
564 | |
445 | This is the general pattern when you "fan out" into multiple subrequests: |
565 | This is the general pattern when you "fan out" into multiple subrequests: |
446 | use an outer C<begin>/C<end> pair to set the callback and ensure C<end> |
566 | use an outer C<begin>/C<end> pair to set the callback and ensure C<end> |
447 | is called at least once, and then, for each subrequest you start, call |
567 | is called at least once, and then, for each subrequest you start, call |
448 | C<begin> and for eahc subrequest you finish, call C<end>. |
568 | C<begin> and for each subrequest you finish, call C<end>. |
449 | |
569 | |
450 | =back |
570 | =back |
451 | |
571 | |
452 | =head3 METHODS FOR CONSUMERS |
572 | =head3 METHODS FOR CONSUMERS |
453 | |
573 | |
… | |
… | |
475 | (programs might want to do that to stay interactive), so I<if you are |
595 | (programs might want to do that to stay interactive), so I<if you are |
476 | using this from a module, never require a blocking wait>, but let the |
596 | using this from a module, never require a blocking wait>, but let the |
477 | caller decide whether the call will block or not (for example, by coupling |
597 | caller decide whether the call will block or not (for example, by coupling |
478 | condition variables with some kind of request results and supporting |
598 | condition variables with some kind of request results and supporting |
479 | callbacks so the caller knows that getting the result will not block, |
599 | callbacks so the caller knows that getting the result will not block, |
480 | while still suppporting blocking waits if the caller so desires). |
600 | while still supporting blocking waits if the caller so desires). |
481 | |
601 | |
482 | Another reason I<never> to C<< ->recv >> in a module is that you cannot |
602 | Another reason I<never> to C<< ->recv >> in a module is that you cannot |
483 | sensibly have two C<< ->recv >>'s in parallel, as that would require |
603 | sensibly have two C<< ->recv >>'s in parallel, as that would require |
484 | multiple interpreters or coroutines/threads, none of which C<AnyEvent> |
604 | multiple interpreters or coroutines/threads, none of which C<AnyEvent> |
485 | can supply. |
605 | can supply. |
… | |
… | |
498 | =item $bool = $cv->ready |
618 | =item $bool = $cv->ready |
499 | |
619 | |
500 | Returns true when the condition is "true", i.e. whether C<send> or |
620 | Returns true when the condition is "true", i.e. whether C<send> or |
501 | C<croak> have been called. |
621 | C<croak> have been called. |
502 | |
622 | |
503 | =item $cb = $cv->cb ([new callback]) |
623 | =item $cb = $cv->cb ($cb->($cv)) |
504 | |
624 | |
505 | This is a mutator function that returns the callback set and optionally |
625 | This is a mutator function that returns the callback set and optionally |
506 | replaces it before doing so. |
626 | replaces it before doing so. |
507 | |
627 | |
508 | The callback will be called when the condition becomes "true", i.e. when |
628 | The callback will be called when the condition becomes "true", i.e. when |
509 | C<send> or C<croak> are called. Calling C<recv> inside the callback |
629 | C<send> or C<croak> are called, with the only argument being the condition |
510 | or at any later time is guaranteed not to block. |
630 | variable itself. Calling C<recv> inside the callback or at any later time |
|
|
631 | is guaranteed not to block. |
511 | |
632 | |
512 | =back |
633 | =back |
513 | |
634 | |
514 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
635 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
515 | |
636 | |
… | |
… | |
601 | |
722 | |
602 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
723 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
603 | do anything special (it does not need to be event-based) and let AnyEvent |
724 | do anything special (it does not need to be event-based) and let AnyEvent |
604 | decide which implementation to chose if some module relies on it. |
725 | decide which implementation to chose if some module relies on it. |
605 | |
726 | |
606 | If the main program relies on a specific event model. For example, in |
727 | If the main program relies on a specific event model - for example, in |
607 | Gtk2 programs you have to rely on the Glib module. You should load the |
728 | Gtk2 programs you have to rely on the Glib module - you should load the |
608 | event module before loading AnyEvent or any module that uses it: generally |
729 | event module before loading AnyEvent or any module that uses it: generally |
609 | speaking, you should load it as early as possible. The reason is that |
730 | speaking, you should load it as early as possible. The reason is that |
610 | modules might create watchers when they are loaded, and AnyEvent will |
731 | modules might create watchers when they are loaded, and AnyEvent will |
611 | decide on the event model to use as soon as it creates watchers, and it |
732 | decide on the event model to use as soon as it creates watchers, and it |
612 | might chose the wrong one unless you load the correct one yourself. |
733 | might chose the wrong one unless you load the correct one yourself. |
613 | |
734 | |
614 | You can chose to use a rather inefficient pure-perl implementation by |
735 | You can chose to use a pure-perl implementation by loading the |
615 | loading the C<AnyEvent::Impl::Perl> module, which gives you similar |
736 | C<AnyEvent::Impl::Perl> module, which gives you similar behaviour |
616 | behaviour everywhere, but letting AnyEvent chose is generally better. |
737 | everywhere, but letting AnyEvent chose the model is generally better. |
|
|
738 | |
|
|
739 | =head2 MAINLOOP EMULATION |
|
|
740 | |
|
|
741 | Sometimes (often for short test scripts, or even standalone programs who |
|
|
742 | only want to use AnyEvent), you do not want to run a specific event loop. |
|
|
743 | |
|
|
744 | In that case, you can use a condition variable like this: |
|
|
745 | |
|
|
746 | AnyEvent->condvar->recv; |
|
|
747 | |
|
|
748 | This has the effect of entering the event loop and looping forever. |
|
|
749 | |
|
|
750 | Note that usually your program has some exit condition, in which case |
|
|
751 | it is better to use the "traditional" approach of storing a condition |
|
|
752 | variable somewhere, waiting for it, and sending it when the program should |
|
|
753 | exit cleanly. |
|
|
754 | |
617 | |
755 | |
618 | =head1 OTHER MODULES |
756 | =head1 OTHER MODULES |
619 | |
757 | |
620 | The following is a non-exhaustive list of additional modules that use |
758 | The following is a non-exhaustive list of additional modules that use |
621 | AnyEvent and can therefore be mixed easily with other AnyEvent modules |
759 | AnyEvent and can therefore be mixed easily with other AnyEvent modules |
… | |
… | |
627 | =item L<AnyEvent::Util> |
765 | =item L<AnyEvent::Util> |
628 | |
766 | |
629 | Contains various utility functions that replace often-used but blocking |
767 | Contains various utility functions that replace often-used but blocking |
630 | functions such as C<inet_aton> by event-/callback-based versions. |
768 | functions such as C<inet_aton> by event-/callback-based versions. |
631 | |
769 | |
|
|
770 | =item L<AnyEvent::Socket> |
|
|
771 | |
|
|
772 | Provides various utility functions for (internet protocol) sockets, |
|
|
773 | addresses and name resolution. Also functions to create non-blocking tcp |
|
|
774 | connections or tcp servers, with IPv6 and SRV record support and more. |
|
|
775 | |
632 | =item L<AnyEvent::Handle> |
776 | =item L<AnyEvent::Handle> |
633 | |
777 | |
634 | Provide read and write buffers and manages watchers for reads and writes. |
778 | Provide read and write buffers, manages watchers for reads and writes, |
|
|
779 | supports raw and formatted I/O, I/O queued and fully transparent and |
|
|
780 | non-blocking SSL/TLS. |
|
|
781 | |
|
|
782 | =item L<AnyEvent::DNS> |
|
|
783 | |
|
|
784 | Provides rich asynchronous DNS resolver capabilities. |
|
|
785 | |
|
|
786 | =item L<AnyEvent::HTTP> |
|
|
787 | |
|
|
788 | A simple-to-use HTTP library that is capable of making a lot of concurrent |
|
|
789 | HTTP requests. |
635 | |
790 | |
636 | =item L<AnyEvent::HTTPD> |
791 | =item L<AnyEvent::HTTPD> |
637 | |
792 | |
638 | Provides a simple web application server framework. |
793 | Provides a simple web application server framework. |
639 | |
794 | |
640 | =item L<AnyEvent::DNS> |
|
|
641 | |
|
|
642 | Provides asynchronous DNS resolver capabilities, beyond what |
|
|
643 | L<AnyEvent::Util> offers. |
|
|
644 | |
|
|
645 | =item L<AnyEvent::FastPing> |
795 | =item L<AnyEvent::FastPing> |
646 | |
796 | |
647 | The fastest ping in the west. |
797 | The fastest ping in the west. |
|
|
798 | |
|
|
799 | =item L<AnyEvent::DBI> |
|
|
800 | |
|
|
801 | Executes L<DBI> requests asynchronously in a proxy process. |
|
|
802 | |
|
|
803 | =item L<AnyEvent::AIO> |
|
|
804 | |
|
|
805 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
806 | programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent |
|
|
807 | together. |
|
|
808 | |
|
|
809 | =item L<AnyEvent::BDB> |
|
|
810 | |
|
|
811 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses |
|
|
812 | L<BDB> and AnyEvent together. |
|
|
813 | |
|
|
814 | =item L<AnyEvent::GPSD> |
|
|
815 | |
|
|
816 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
|
|
817 | |
|
|
818 | =item L<AnyEvent::IGS> |
|
|
819 | |
|
|
820 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
821 | L<App::IGS>). |
648 | |
822 | |
649 | =item L<Net::IRC3> |
823 | =item L<Net::IRC3> |
650 | |
824 | |
651 | AnyEvent based IRC client module family. |
825 | AnyEvent based IRC client module family. |
652 | |
826 | |
… | |
… | |
665 | |
839 | |
666 | =item L<Coro> |
840 | =item L<Coro> |
667 | |
841 | |
668 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
842 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
669 | |
843 | |
670 | =item L<AnyEvent::AIO>, L<IO::AIO> |
|
|
671 | |
|
|
672 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
673 | programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent |
|
|
674 | together. |
|
|
675 | |
|
|
676 | =item L<AnyEvent::BDB>, L<BDB> |
|
|
677 | |
|
|
678 | Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently fuses |
|
|
679 | IO::AIO and AnyEvent together. |
|
|
680 | |
|
|
681 | =item L<IO::Lambda> |
844 | =item L<IO::Lambda> |
682 | |
845 | |
683 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
846 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
684 | |
847 | |
685 | =back |
848 | =back |
… | |
… | |
691 | no warnings; |
854 | no warnings; |
692 | use strict; |
855 | use strict; |
693 | |
856 | |
694 | use Carp; |
857 | use Carp; |
695 | |
858 | |
696 | our $VERSION = '3.5'; |
859 | our $VERSION = 4.231; |
697 | our $MODEL; |
860 | our $MODEL; |
698 | |
861 | |
699 | our $AUTOLOAD; |
862 | our $AUTOLOAD; |
700 | our @ISA; |
863 | our @ISA; |
701 | |
864 | |
|
|
865 | our @REGISTRY; |
|
|
866 | |
|
|
867 | our $WIN32; |
|
|
868 | |
|
|
869 | BEGIN { |
|
|
870 | my $win32 = ! ! ($^O =~ /mswin32/i); |
|
|
871 | eval "sub WIN32(){ $win32 }"; |
|
|
872 | } |
|
|
873 | |
702 | our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
874 | our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
703 | |
875 | |
704 | our @REGISTRY; |
876 | our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred |
|
|
877 | |
|
|
878 | { |
|
|
879 | my $idx; |
|
|
880 | $PROTOCOL{$_} = ++$idx |
|
|
881 | for reverse split /\s*,\s*/, |
|
|
882 | $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; |
|
|
883 | } |
705 | |
884 | |
706 | my @models = ( |
885 | my @models = ( |
707 | [EV:: => AnyEvent::Impl::EV::], |
886 | [EV:: => AnyEvent::Impl::EV::], |
708 | [Event:: => AnyEvent::Impl::Event::], |
887 | [Event:: => AnyEvent::Impl::Event::], |
709 | [Tk:: => AnyEvent::Impl::Tk::], |
|
|
710 | [Wx:: => AnyEvent::Impl::POE::], |
|
|
711 | [Prima:: => AnyEvent::Impl::POE::], |
|
|
712 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], |
888 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], |
713 | # everything below here will not be autoprobed as the pureperl backend should work everywhere |
889 | # everything below here will not be autoprobed |
714 | [Glib:: => AnyEvent::Impl::Glib::], |
890 | # as the pureperl backend should work everywhere |
|
|
891 | # and is usually faster |
|
|
892 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
|
|
893 | [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers |
715 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
894 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
716 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
895 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
717 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
896 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
|
|
897 | [Wx:: => AnyEvent::Impl::POE::], |
|
|
898 | [Prima:: => AnyEvent::Impl::POE::], |
718 | ); |
899 | ); |
719 | |
900 | |
720 | our %method = map +($_ => 1), qw(io timer signal child condvar one_event DESTROY); |
901 | our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY); |
721 | |
902 | |
722 | our @post_detect; |
903 | our @post_detect; |
723 | |
904 | |
724 | sub post_detect(&) { |
905 | sub post_detect(&) { |
725 | my ($cb) = @_; |
906 | my ($cb) = @_; |
… | |
… | |
742 | } |
923 | } |
743 | |
924 | |
744 | sub detect() { |
925 | sub detect() { |
745 | unless ($MODEL) { |
926 | unless ($MODEL) { |
746 | no strict 'refs'; |
927 | no strict 'refs'; |
|
|
928 | local $SIG{__DIE__}; |
747 | |
929 | |
748 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
930 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
749 | my $model = "AnyEvent::Impl::$1"; |
931 | my $model = "AnyEvent::Impl::$1"; |
750 | if (eval "require $model") { |
932 | if (eval "require $model") { |
751 | $MODEL = $model; |
933 | $MODEL = $model; |
… | |
… | |
785 | $MODEL |
967 | $MODEL |
786 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
968 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
787 | } |
969 | } |
788 | } |
970 | } |
789 | |
971 | |
|
|
972 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
973 | |
790 | unshift @ISA, $MODEL; |
974 | unshift @ISA, $MODEL; |
791 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
975 | |
|
|
976 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
792 | |
977 | |
793 | (shift @post_detect)->() while @post_detect; |
978 | (shift @post_detect)->() while @post_detect; |
794 | } |
979 | } |
795 | |
980 | |
796 | $MODEL |
981 | $MODEL |
… | |
… | |
806 | |
991 | |
807 | my $class = shift; |
992 | my $class = shift; |
808 | $class->$func (@_); |
993 | $class->$func (@_); |
809 | } |
994 | } |
810 | |
995 | |
|
|
996 | # utility function to dup a filehandle. this is used by many backends |
|
|
997 | # to support binding more than one watcher per filehandle (they usually |
|
|
998 | # allow only one watcher per fd, so we dup it to get a different one). |
|
|
999 | sub _dupfh($$$$) { |
|
|
1000 | my ($poll, $fh, $r, $w) = @_; |
|
|
1001 | |
|
|
1002 | require Fcntl; |
|
|
1003 | |
|
|
1004 | # cygwin requires the fh mode to be matching, unix doesn't |
|
|
1005 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
|
|
1006 | : $poll eq "w" ? ($w, ">") |
|
|
1007 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
|
|
1008 | |
|
|
1009 | open my $fh2, "$mode&" . fileno $fh |
|
|
1010 | or die "cannot dup() filehandle: $!"; |
|
|
1011 | |
|
|
1012 | # we assume CLOEXEC is already set by perl in all important cases |
|
|
1013 | |
|
|
1014 | ($fh2, $rw) |
|
|
1015 | } |
|
|
1016 | |
811 | package AnyEvent::Base; |
1017 | package AnyEvent::Base; |
812 | |
1018 | |
|
|
1019 | # default implementation for now and time |
|
|
1020 | |
|
|
1021 | use Time::HiRes (); |
|
|
1022 | |
|
|
1023 | sub time { Time::HiRes::time } |
|
|
1024 | sub now { Time::HiRes::time } |
|
|
1025 | |
813 | # default implementation for ->condvar |
1026 | # default implementation for ->condvar |
814 | |
1027 | |
815 | sub condvar { |
1028 | sub condvar { |
816 | bless {}, AnyEvent::CondVar:: |
1029 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
817 | } |
1030 | } |
818 | |
1031 | |
819 | # default implementation for ->signal |
1032 | # default implementation for ->signal |
820 | |
1033 | |
821 | our %SIG_CB; |
1034 | our %SIG_CB; |
… | |
… | |
837 | sub AnyEvent::Base::Signal::DESTROY { |
1050 | sub AnyEvent::Base::Signal::DESTROY { |
838 | my ($signal, $cb) = @{$_[0]}; |
1051 | my ($signal, $cb) = @{$_[0]}; |
839 | |
1052 | |
840 | delete $SIG_CB{$signal}{$cb}; |
1053 | delete $SIG_CB{$signal}{$cb}; |
841 | |
1054 | |
842 | $SIG{$signal} = 'DEFAULT' unless keys %{ $SIG_CB{$signal} }; |
1055 | delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
843 | } |
1056 | } |
844 | |
1057 | |
845 | # default implementation for ->child |
1058 | # default implementation for ->child |
846 | |
1059 | |
847 | our %PID_CB; |
1060 | our %PID_CB; |
… | |
… | |
874 | or Carp::croak "required option 'pid' is missing"; |
1087 | or Carp::croak "required option 'pid' is missing"; |
875 | |
1088 | |
876 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1089 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
877 | |
1090 | |
878 | unless ($WNOHANG) { |
1091 | unless ($WNOHANG) { |
879 | $WNOHANG = eval { require POSIX; &POSIX::WNOHANG } || 1; |
1092 | $WNOHANG = eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
880 | } |
1093 | } |
881 | |
1094 | |
882 | unless ($CHLD_W) { |
1095 | unless ($CHLD_W) { |
883 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1096 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
884 | # child could be a zombie already, so make at least one round |
1097 | # child could be a zombie already, so make at least one round |
… | |
… | |
901 | |
1114 | |
902 | our @ISA = AnyEvent::CondVar::Base::; |
1115 | our @ISA = AnyEvent::CondVar::Base::; |
903 | |
1116 | |
904 | package AnyEvent::CondVar::Base; |
1117 | package AnyEvent::CondVar::Base; |
905 | |
1118 | |
|
|
1119 | use overload |
|
|
1120 | '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
|
|
1121 | fallback => 1; |
|
|
1122 | |
906 | sub _send { |
1123 | sub _send { |
907 | # nop |
1124 | # nop |
908 | } |
1125 | } |
909 | |
1126 | |
910 | sub send { |
1127 | sub send { |
… | |
… | |
944 | $_[0]{_ae_end_cb} = $_[1] if @_ > 1; |
1161 | $_[0]{_ae_end_cb} = $_[1] if @_ > 1; |
945 | } |
1162 | } |
946 | |
1163 | |
947 | sub end { |
1164 | sub end { |
948 | return if --$_[0]{_ae_counter}; |
1165 | return if --$_[0]{_ae_counter}; |
949 | &{ $_[0]{_ae_end_cb} } if $_[0]{_ae_end_cb}; |
1166 | &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; |
950 | } |
1167 | } |
951 | |
1168 | |
952 | # undocumented/compatibility with pre-3.4 |
1169 | # undocumented/compatibility with pre-3.4 |
953 | *broadcast = \&send; |
1170 | *broadcast = \&send; |
954 | *wait = \&_wait; |
1171 | *wait = \&_wait; |
… | |
… | |
1013 | C<PERL_ANYEVENT_MODEL>. |
1230 | C<PERL_ANYEVENT_MODEL>. |
1014 | |
1231 | |
1015 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
1232 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
1016 | model it chooses. |
1233 | model it chooses. |
1017 | |
1234 | |
|
|
1235 | =item C<PERL_ANYEVENT_STRICT> |
|
|
1236 | |
|
|
1237 | AnyEvent does not do much argument checking by default, as thorough |
|
|
1238 | argument checking is very costly. Setting this variable to a true value |
|
|
1239 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
|
|
1240 | check the arguments passed to most method calls. If it finds any problems |
|
|
1241 | it will croak. |
|
|
1242 | |
|
|
1243 | In other words, enables "strict" mode. |
|
|
1244 | |
|
|
1245 | Unlike C<use strict> it is definitely recommended ot keep it off in |
|
|
1246 | production. |
|
|
1247 | |
1018 | =item C<PERL_ANYEVENT_MODEL> |
1248 | =item C<PERL_ANYEVENT_MODEL> |
1019 | |
1249 | |
1020 | This can be used to specify the event model to be used by AnyEvent, before |
1250 | This can be used to specify the event model to be used by AnyEvent, before |
1021 | autodetection and -probing kicks in. It must be a string consisting |
1251 | auto detection and -probing kicks in. It must be a string consisting |
1022 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
1252 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
1023 | and the resulting module name is loaded and if the load was successful, |
1253 | and the resulting module name is loaded and if the load was successful, |
1024 | used as event model. If it fails to load AnyEvent will proceed with |
1254 | used as event model. If it fails to load AnyEvent will proceed with |
1025 | autodetection and -probing. |
1255 | auto detection and -probing. |
1026 | |
1256 | |
1027 | This functionality might change in future versions. |
1257 | This functionality might change in future versions. |
1028 | |
1258 | |
1029 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
1259 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
1030 | could start your program like this: |
1260 | could start your program like this: |
1031 | |
1261 | |
1032 | PERL_ANYEVENT_MODEL=Perl perl ... |
1262 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1263 | |
|
|
1264 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1265 | |
|
|
1266 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1267 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1268 | of auto probing). |
|
|
1269 | |
|
|
1270 | Must be set to a comma-separated list of protocols or address families, |
|
|
1271 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1272 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1273 | list. |
|
|
1274 | |
|
|
1275 | This variable can effectively be used for denial-of-service attacks |
|
|
1276 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1277 | small, as the program has to handle connection errors already- |
|
|
1278 | |
|
|
1279 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1280 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1281 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1282 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1283 | IPv6, but prefer IPv6 over IPv4. |
|
|
1284 | |
|
|
1285 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1286 | |
|
|
1287 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1288 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1289 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1290 | default. |
|
|
1291 | |
|
|
1292 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1293 | EDNS0 in its DNS requests. |
|
|
1294 | |
|
|
1295 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1296 | |
|
|
1297 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1298 | will create in parallel. |
1033 | |
1299 | |
1034 | =back |
1300 | =back |
1035 | |
1301 | |
1036 | =head1 EXAMPLE PROGRAM |
1302 | =head1 EXAMPLE PROGRAM |
1037 | |
1303 | |
… | |
… | |
1123 | syswrite $txn->{fh}, $txn->{request} |
1389 | syswrite $txn->{fh}, $txn->{request} |
1124 | or die "connection or write error"; |
1390 | or die "connection or write error"; |
1125 | $txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r }); |
1391 | $txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r }); |
1126 | |
1392 | |
1127 | Again, C<fh_ready_r> waits till all data has arrived, and then stores the |
1393 | Again, C<fh_ready_r> waits till all data has arrived, and then stores the |
1128 | result and signals any possible waiters that the request ahs finished: |
1394 | result and signals any possible waiters that the request has finished: |
1129 | |
1395 | |
1130 | sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf}; |
1396 | sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf}; |
1131 | |
1397 | |
1132 | if (end-of-file or data complete) { |
1398 | if (end-of-file or data complete) { |
1133 | $txn->{result} = $txn->{buf}; |
1399 | $txn->{result} = $txn->{buf}; |
… | |
… | |
1141 | |
1407 | |
1142 | $txn->{finished}->recv; |
1408 | $txn->{finished}->recv; |
1143 | return $txn->{result}; |
1409 | return $txn->{result}; |
1144 | |
1410 | |
1145 | The actual code goes further and collects all errors (C<die>s, exceptions) |
1411 | The actual code goes further and collects all errors (C<die>s, exceptions) |
1146 | that occured during request processing. The C<result> method detects |
1412 | that occurred during request processing. The C<result> method detects |
1147 | whether an exception as thrown (it is stored inside the $txn object) |
1413 | whether an exception as thrown (it is stored inside the $txn object) |
1148 | and just throws the exception, which means connection errors and other |
1414 | and just throws the exception, which means connection errors and other |
1149 | problems get reported tot he code that tries to use the result, not in a |
1415 | problems get reported tot he code that tries to use the result, not in a |
1150 | random callback. |
1416 | random callback. |
1151 | |
1417 | |
… | |
… | |
1197 | of various event loops I prepared some benchmarks. |
1463 | of various event loops I prepared some benchmarks. |
1198 | |
1464 | |
1199 | =head2 BENCHMARKING ANYEVENT OVERHEAD |
1465 | =head2 BENCHMARKING ANYEVENT OVERHEAD |
1200 | |
1466 | |
1201 | Here is a benchmark of various supported event models used natively and |
1467 | Here is a benchmark of various supported event models used natively and |
1202 | through anyevent. The benchmark creates a lot of timers (with a zero |
1468 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
1203 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
1469 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
1204 | which it is), lets them fire exactly once and destroys them again. |
1470 | which it is), lets them fire exactly once and destroys them again. |
1205 | |
1471 | |
1206 | Source code for this benchmark is found as F<eg/bench> in the AnyEvent |
1472 | Source code for this benchmark is found as F<eg/bench> in the AnyEvent |
1207 | distribution. |
1473 | distribution. |
… | |
… | |
1330 | |
1596 | |
1331 | =back |
1597 | =back |
1332 | |
1598 | |
1333 | =head2 BENCHMARKING THE LARGE SERVER CASE |
1599 | =head2 BENCHMARKING THE LARGE SERVER CASE |
1334 | |
1600 | |
1335 | This benchmark atcually benchmarks the event loop itself. It works by |
1601 | This benchmark actually benchmarks the event loop itself. It works by |
1336 | creating a number of "servers": each server consists of a socketpair, a |
1602 | creating a number of "servers": each server consists of a socket pair, a |
1337 | timeout watcher that gets reset on activity (but never fires), and an I/O |
1603 | timeout watcher that gets reset on activity (but never fires), and an I/O |
1338 | watcher waiting for input on one side of the socket. Each time the socket |
1604 | watcher waiting for input on one side of the socket. Each time the socket |
1339 | watcher reads a byte it will write that byte to a random other "server". |
1605 | watcher reads a byte it will write that byte to a random other "server". |
1340 | |
1606 | |
1341 | The effect is that there will be a lot of I/O watchers, only part of which |
1607 | The effect is that there will be a lot of I/O watchers, only part of which |
1342 | are active at any one point (so there is a constant number of active |
1608 | are active at any one point (so there is a constant number of active |
1343 | fds for each loop iterstaion, but which fds these are is random). The |
1609 | fds for each loop iteration, but which fds these are is random). The |
1344 | timeout is reset each time something is read because that reflects how |
1610 | timeout is reset each time something is read because that reflects how |
1345 | most timeouts work (and puts extra pressure on the event loops). |
1611 | most timeouts work (and puts extra pressure on the event loops). |
1346 | |
1612 | |
1347 | In this benchmark, we use 10000 socketpairs (20000 sockets), of which 100 |
1613 | In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100 |
1348 | (1%) are active. This mirrors the activity of large servers with many |
1614 | (1%) are active. This mirrors the activity of large servers with many |
1349 | connections, most of which are idle at any one point in time. |
1615 | connections, most of which are idle at any one point in time. |
1350 | |
1616 | |
1351 | Source code for this benchmark is found as F<eg/bench2> in the AnyEvent |
1617 | Source code for this benchmark is found as F<eg/bench2> in the AnyEvent |
1352 | distribution. |
1618 | distribution. |
… | |
… | |
1354 | =head3 Explanation of the columns |
1620 | =head3 Explanation of the columns |
1355 | |
1621 | |
1356 | I<sockets> is the number of sockets, and twice the number of "servers" (as |
1622 | I<sockets> is the number of sockets, and twice the number of "servers" (as |
1357 | each server has a read and write socket end). |
1623 | each server has a read and write socket end). |
1358 | |
1624 | |
1359 | I<create> is the time it takes to create a socketpair (which is |
1625 | I<create> is the time it takes to create a socket pair (which is |
1360 | nontrivial) and two watchers: an I/O watcher and a timeout watcher. |
1626 | nontrivial) and two watchers: an I/O watcher and a timeout watcher. |
1361 | |
1627 | |
1362 | I<request>, the most important value, is the time it takes to handle a |
1628 | I<request>, the most important value, is the time it takes to handle a |
1363 | single "request", that is, reading the token from the pipe and forwarding |
1629 | single "request", that is, reading the token from the pipe and forwarding |
1364 | it to another server. This includes deleting the old timeout and creating |
1630 | it to another server. This includes deleting the old timeout and creating |
… | |
… | |
1437 | speed most when you have lots of watchers, not when you only have a few of |
1703 | speed most when you have lots of watchers, not when you only have a few of |
1438 | them). |
1704 | them). |
1439 | |
1705 | |
1440 | EV is again fastest. |
1706 | EV is again fastest. |
1441 | |
1707 | |
1442 | Perl again comes second. It is noticably faster than the C-based event |
1708 | Perl again comes second. It is noticeably faster than the C-based event |
1443 | loops Event and Glib, although the difference is too small to really |
1709 | loops Event and Glib, although the difference is too small to really |
1444 | matter. |
1710 | matter. |
1445 | |
1711 | |
1446 | POE also performs much better in this case, but is is still far behind the |
1712 | POE also performs much better in this case, but is is still far behind the |
1447 | others. |
1713 | others. |
… | |
… | |
1476 | specified in the variable. |
1742 | specified in the variable. |
1477 | |
1743 | |
1478 | You can make AnyEvent completely ignore this variable by deleting it |
1744 | You can make AnyEvent completely ignore this variable by deleting it |
1479 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
1745 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
1480 | |
1746 | |
1481 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1747 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1482 | |
1748 | |
1483 | use AnyEvent; |
1749 | use AnyEvent; |
1484 | |
1750 | |
1485 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1751 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1486 | be used to probe what backend is used and gain other information (which is |
1752 | be used to probe what backend is used and gain other information (which is |
1487 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL). |
1753 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
|
|
1754 | $ENV{PERL_ANYEGENT_STRICT}. |
|
|
1755 | |
|
|
1756 | |
|
|
1757 | =head1 BUGS |
|
|
1758 | |
|
|
1759 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
|
|
1760 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
|
|
1761 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
|
|
1762 | mamleaks, such as leaking on C<map> and C<grep> but it is usually not as |
|
|
1763 | pronounced). |
1488 | |
1764 | |
1489 | |
1765 | |
1490 | =head1 SEE ALSO |
1766 | =head1 SEE ALSO |
|
|
1767 | |
|
|
1768 | Utility functions: L<AnyEvent::Util>. |
1491 | |
1769 | |
1492 | Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, |
1770 | Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, |
1493 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
1771 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
1494 | |
1772 | |
1495 | Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, |
1773 | Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, |
1496 | L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, |
1774 | L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, |
1497 | L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, |
1775 | L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, |
1498 | L<AnyEvent::Impl::POE>. |
1776 | L<AnyEvent::Impl::POE>. |
1499 | |
1777 | |
|
|
1778 | Non-blocking file handles, sockets, TCP clients and |
|
|
1779 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>. |
|
|
1780 | |
|
|
1781 | Asynchronous DNS: L<AnyEvent::DNS>. |
|
|
1782 | |
1500 | Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>, |
1783 | Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>, |
1501 | |
1784 | |
1502 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>. |
1785 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. |
1503 | |
1786 | |
1504 | |
1787 | |
1505 | =head1 AUTHOR |
1788 | =head1 AUTHOR |
1506 | |
1789 | |
1507 | Marc Lehmann <schmorp@schmorp.de> |
1790 | Marc Lehmann <schmorp@schmorp.de> |
1508 | http://home.schmorp.de/ |
1791 | http://home.schmorp.de/ |
1509 | |
1792 | |
1510 | =cut |
1793 | =cut |
1511 | |
1794 | |
1512 | 1 |
1795 | 1 |
1513 | |
1796 | |