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Comparing Coro/Coro.pm (file contents):
Revision 1.33 by root, Sun Sep 16 00:44:05 2001 UTC vs.
Revision 1.56 by pcg, Sat Nov 15 03:53:10 2003 UTC

19 cede; 19 cede;
20 20
21=head1 DESCRIPTION 21=head1 DESCRIPTION
22 22
23This module collection manages coroutines. Coroutines are similar to 23This module collection manages coroutines. Coroutines are similar to
24Threads but don't run in parallel. 24threads but don't run in parallel.
25
26This module is still experimental, see the BUGS section below.
27 25
28In this module, coroutines are defined as "callchain + lexical variables 26In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own 27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most 28callchain, it's own set of lexicals and it's own set of perl's most
31important global variables. 29important global variables.
32 30
33=cut 31=cut
34 32
35package Coro; 33package Coro;
36 34
35BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
36
37use Coro::State; 37use Coro::State;
38 38
39use vars qw($idle $main $current);
40
39use base Exporter; 41use base Exporter;
40 42
41$VERSION = 0.49; 43$VERSION = "0.9";
42 44
43@EXPORT = qw(async cede schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
44%EXPORT_TAGS = ( 46%EXPORT_TAGS = (
45 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 47 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
46); 48);
75 }; 77 };
76 } 78 }
77 79
78} 80}
79 81
82=over 4
83
80=item $main 84=item $main
81 85
82This coroutine represents the main program. 86This coroutine represents the main program.
83 87
84=cut 88=cut
85 89
86our $main = new Coro; 90$main = new Coro;
87 91
88=item $current (or as function: current) 92=item $current (or as function: current)
89 93
90The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 94The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
91 95
94# maybe some other module used Coro::Specific before... 98# maybe some other module used Coro::Specific before...
95if ($current) { 99if ($current) {
96 $main->{specific} = $current->{specific}; 100 $main->{specific} = $current->{specific};
97} 101}
98 102
99our $current = $main; 103$current = $main;
100 104
101sub current() { $current } 105sub current() { $current }
102 106
103=item $idle 107=item $idle
104 108
106implementation prints "FATAL: deadlock detected" and exits. 110implementation prints "FATAL: deadlock detected" and exits.
107 111
108=cut 112=cut
109 113
110# should be done using priorities :( 114# should be done using priorities :(
111our $idle = new Coro sub { 115$idle = new Coro sub {
112 print STDERR "FATAL: deadlock detected\n"; 116 print STDERR "FATAL: deadlock detected\n";
113 exit(51); 117 exit(51);
114}; 118};
115 119
116# this coroutine is necessary because a coroutine 120# this coroutine is necessary because a coroutine
117# cannot destroy itself. 121# cannot destroy itself.
118my @destroy; 122my @destroy;
123my $manager;
119my $manager = new Coro sub { 124$manager = new Coro sub {
120 while() { 125 while() {
121 delete ((pop @destroy)->{_coro_state}) while @destroy; 126 # by overwriting the state object with the manager we destroy it
127 # while still being able to schedule this coroutine (in case it has
128 # been readied multiple times. this is harmless since the manager
129 # can be called as many times as neccessary and will always
130 # remove itself from the runqueue
131 while (@destroy) {
132 my $coro = pop @destroy;
133 $coro->{status} ||= [];
134 $_->ready for @{delete $coro->{join} || []};
135 $coro->{_coro_state} = $manager->{_coro_state};
136 }
122 &schedule; 137 &schedule;
123 } 138 }
124}; 139};
125 140
126# static methods. not really. 141# static methods. not really.
142
143=back
127 144
128=head2 STATIC METHODS 145=head2 STATIC METHODS
129 146
130Static methods are actually functions that operate on the current process only. 147Static methods are actually functions that operate on the current process only.
131 148
168ready queue and calls C<schedule>, which has the effect of giving up the 185ready queue and calls C<schedule>, which has the effect of giving up the
169current "timeslice" to other coroutines of the same or higher priority. 186current "timeslice" to other coroutines of the same or higher priority.
170 187
171=cut 188=cut
172 189
173=item terminate 190=item terminate [arg...]
174 191
175Terminates the current process. 192Terminates the current process.
176 193
177Future versions of this function will allow result arguments. 194Future versions of this function will allow result arguments.
178 195
179=cut 196=cut
180 197
181sub terminate { 198sub terminate {
199 $current->{status} = [@_];
182 $current->cancel; 200 $current->cancel;
183 &schedule; 201 &schedule;
184 die; # NORETURN 202 die; # NORETURN
185} 203}
186 204
195=over 4 213=over 4
196 214
197=item new Coro \&sub [, @args...] 215=item new Coro \&sub [, @args...]
198 216
199Create a new process and return it. When the sub returns the process 217Create a new process and return it. When the sub returns the process
200automatically terminates. To start the process you must first put it into 218automatically terminates as if C<terminate> with the returned values were
219called. To make the process run you must first put it into the ready queue
201the ready queue by calling the ready method. 220by calling the ready method.
202
203The coderef you submit MUST NOT be a closure that refers to variables
204in an outer scope. This does NOT work. Pass arguments into it instead.
205 221
206=cut 222=cut
207 223
208sub _newcoro { 224sub _newcoro {
209 terminate &{+shift}; 225 terminate &{+shift};
216 }, $class; 232 }, $class;
217} 233}
218 234
219=item $process->ready 235=item $process->ready
220 236
221Put the current process into the ready queue. 237Put the given process into the ready queue.
222 238
223=cut 239=cut
224 240
225=item $process->cancel 241=item $process->cancel
226 242
229=cut 245=cut
230 246
231sub cancel { 247sub cancel {
232 push @destroy, $_[0]; 248 push @destroy, $_[0];
233 $manager->ready; 249 $manager->ready;
250 &schedule if $current == $_[0];
251}
252
253=item $process->join
254
255Wait until the coroutine terminates and return any values given to the
256C<terminate> function. C<join> can be called multiple times from multiple
257processes.
258
259=cut
260
261sub join {
262 my $self = shift;
263 unless ($self->{status}) {
264 push @{$self->{join}}, $current;
265 &schedule;
266 }
267 wantarray ? @{$self->{status}} : $self->{status}[0];
234} 268}
235 269
236=item $oldprio = $process->prio($newprio) 270=item $oldprio = $process->prio($newprio)
237 271
238Sets the priority of the process. Higher priority processes get run before 272Sets (or gets, if the argument is missing) the priority of the
273process. Higher priority processes get run before lower priority
239lower priority processes. Priorities are smalled signed integer (currently 274processes. Priorities are small signed integers (currently -4 .. +3),
240-4 .. +3), that you can refer to using PRIO_xxx constants (use the import 275that you can refer to using PRIO_xxx constants (use the import tag :prio
241tag :prio to get then): 276to get then):
242 277
243 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN 278 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
244 3 > 1 > 0 > -1 > -3 > -4 279 3 > 1 > 0 > -1 > -3 > -4
245 280
246 # set priority to HIGH 281 # set priority to HIGH
271 306
272sub nice { 307sub nice {
273 $_[0]{prio} -= $_[1]; 308 $_[0]{prio} -= $_[1];
274} 309}
275 310
311=item $olddesc = $process->desc($newdesc)
312
313Sets (or gets in case the argument is missing) the description for this
314process. This is just a free-form string you can associate with a process.
315
316=cut
317
318sub desc {
319 my $old = $_[0]{desc};
320 $_[0]{desc} = $_[1] if @_ > 1;
321 $old;
322}
323
276=back 324=back
277 325
278=cut 326=cut
279 327
2801; 3281;
281 329
282=head1 BUGS/LIMITATIONS 330=head1 BUGS/LIMITATIONS
283 331
284 - you must make very sure that no coro is still active on global destruction. 332 - you must make very sure that no coro is still active on global
285 very bad things might happen otherwise (usually segfaults). 333 destruction. very bad things might happen otherwise (usually segfaults).
334
286 - this module is not thread-safe. You must only ever use this module from 335 - this module is not thread-safe. You should only ever use this module
287 the same thread (this requirement might be loosened in the future to 336 from the same thread (this requirement might be losened in the future
288 allow per-thread schedulers, but Coro::State does not yet allow this). 337 to allow per-thread schedulers, but Coro::State does not yet allow
338 this).
289 339
290=head1 SEE ALSO 340=head1 SEE ALSO
291 341
292L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 342L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
293L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>, 343L<Coro::Signal>, L<Coro::State>, L<Coro::Timer>, L<Coro::Event>,
294L<Coro::Handle>, L<Coro::Socket>. 344L<Coro::L<Coro::RWLock>, Handle>, L<Coro::Socket>.
295 345
296=head1 AUTHOR 346=head1 AUTHOR
297 347
298 Marc Lehmann <pcg@goof.com> 348 Marc Lehmann <pcg@goof.com>
299 http://www.goof.com/pcg/marc/ 349 http://www.goof.com/pcg/marc/

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