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Comparing Coro/Coro.pm (file contents):
Revision 1.30 by root, Sat Aug 11 19:59:19 2001 UTC vs.
Revision 1.51 by root, Thu May 8 00:55:28 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most 28callchain, it's own set of lexicals and it's own set of perl's most
31important global variables. 29important global variables.
32 30
33=cut 31=cut
34 32
35package Coro; 33package Coro;
36 34
35no warnings qw(uninitialized);
36
37use Coro::State; 37use Coro::State;
38 38
39use base Exporter; 39use base Exporter;
40 40
41$VERSION = 0.45; 41$VERSION = 0.652;
42 42
43@EXPORT = qw(async cede schedule terminate current); 43@EXPORT = qw(async cede schedule terminate current);
44@EXPORT_OK = qw($current); 44%EXPORT_TAGS = (
45 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
46);
47@EXPORT_OK = @{$EXPORT_TAGS{prio}};
45 48
46{ 49{
47 my @async; 50 my @async;
48 my $init; 51 my $init;
49 52
… …
72 }; 75 };
73 } 76 }
74 77
75} 78}
76 79
80=over 4
81
77=item $main 82=item $main
78 83
79This coroutine represents the main program. 84This coroutine represents the main program.
80 85
81=cut 86=cut
… …
111}; 116};
112 117
113# this coroutine is necessary because a coroutine 118# this coroutine is necessary because a coroutine
114# cannot destroy itself. 119# cannot destroy itself.
115my @destroy; 120my @destroy;
121my $manager;
116my $manager = new Coro sub { 122$manager = new Coro sub {
117 while() { 123 while() {
118 delete ((pop @destroy)->{_coro_state}) while @destroy; 124 # by overwriting the state object with the manager we destroy it
125 # while still being able to schedule this coroutine (in case it has
126 # been readied multiple times. this is harmless since the manager
127 # can be called as many times as neccessary and will always
128 # remove itself from the runqueue
129 while (@destroy) {
130 my $coro = pop @destroy;
131 $coro->{status} ||= [];
132 $_->ready for @{delete $coro->{join} || []};
133 $coro->{_coro_state} = $manager->{_coro_state};
134 }
119 &schedule; 135 &schedule;
120 } 136 }
121}; 137};
122 138
123# static methods. not really. 139# static methods. not really.
140
141=back
124 142
125=head2 STATIC METHODS 143=head2 STATIC METHODS
126 144
127Static methods are actually functions that operate on the current process only. 145Static methods are actually functions that operate on the current process only.
128 146
… …
165ready queue and calls C<schedule>, which has the effect of giving up the 183ready queue and calls C<schedule>, which has the effect of giving up the
166current "timeslice" to other coroutines of the same or higher priority. 184current "timeslice" to other coroutines of the same or higher priority.
167 185
168=cut 186=cut
169 187
170=item terminate 188=item terminate [arg...]
171 189
172Terminates the current process. 190Terminates the current process.
173 191
174Future versions of this function will allow result arguments. 192Future versions of this function will allow result arguments.
175 193
176=cut 194=cut
177 195
178sub terminate { 196sub terminate {
197 $current->{status} = [@_];
179 $current->cancel; 198 $current->cancel;
180 &schedule; 199 &schedule;
181 die; # NORETURN 200 die; # NORETURN
182} 201}
183 202
… …
192=over 4 211=over 4
193 212
194=item new Coro \&sub [, @args...] 213=item new Coro \&sub [, @args...]
195 214
196Create a new process and return it. When the sub returns the process 215Create a new process and return it. When the sub returns the process
197automatically terminates. To start the process you must first put it into 216automatically terminates as if C<terminate> with the returned values were
217called. To make the process run you must first put it into the ready queue
198the ready queue by calling the ready method. 218by calling the ready method.
199
200The coderef you submit MUST NOT be a closure that refers to variables
201in an outer scope. This does NOT work. Pass arguments into it instead.
202 219
203=cut 220=cut
204 221
205sub _newcoro { 222sub _newcoro {
206 terminate &{+shift}; 223 terminate &{+shift};
… …
213 }, $class; 230 }, $class;
214} 231}
215 232
216=item $process->ready 233=item $process->ready
217 234
218Put the current process into the ready queue. 235Put the given process into the ready queue.
219 236
220=cut 237=cut
221 238
222=item $process->cancel 239=item $process->cancel
223 240
… …
226=cut 243=cut
227 244
228sub cancel { 245sub cancel {
229 push @destroy, $_[0]; 246 push @destroy, $_[0];
230 $manager->ready; 247 $manager->ready;
248 &schedule if $current == $_[0];
249}
250
251=item $process->join
252
253Wait until the coroutine terminates and return any values given to the
254C<terminate> function. C<join> can be called multiple times from multiple
255processes.
256
257=cut
258
259sub join {
260 my $self = shift;
261 unless ($self->{status}) {
262 push @{$self->{join}}, $current;
263 &schedule;
264 }
265 wantarray ? @{$self->{status}} : $self->{status}[0];
266}
267
268=item $oldprio = $process->prio($newprio)
269
270Sets (or gets, if the argument is missing) the priority of the
271process. Higher priority processes get run before lower priority
272processes. Priorities are smalled signed integer (currently -4 .. +3),
273that you can refer to using PRIO_xxx constants (use the import tag :prio
274to get then):
275
276 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
277 3 > 1 > 0 > -1 > -3 > -4
278
279 # set priority to HIGH
280 current->prio(PRIO_HIGH);
281
282The idle coroutine ($Coro::idle) always has a lower priority than any
283existing coroutine.
284
285Changing the priority of the current process will take effect immediately,
286but changing the priority of processes in the ready queue (but not
287running) will only take effect after the next schedule (of that
288process). This is a bug that will be fixed in some future version.
289
290=cut
291
292sub prio {
293 my $old = $_[0]{prio};
294 $_[0]{prio} = $_[1] if @_ > 1;
295 $old;
296}
297
298=item $newprio = $process->nice($change)
299
300Similar to C<prio>, but subtract the given value from the priority (i.e.
301higher values mean lower priority, just as in unix).
302
303=cut
304
305sub nice {
306 $_[0]{prio} -= $_[1];
307}
308
309=item $olddesc = $process->desc($newdesc)
310
311Sets (or gets in case the argument is missing) the description for this
312process. This is just a free-form string you can associate with a process.
313
314=cut
315
316sub desc {
317 my $old = $_[0]{desc};
318 $_[0]{desc} = $_[1] if @_ > 1;
319 $old;
231} 320}
232 321
233=back 322=back
234 323
235=cut 324=cut
236 325
2371; 3261;
238 327
239=head1 BUGS/LIMITATIONS 328=head1 BUGS/LIMITATIONS
240 329
241 - could be faster, especially when the core would introduce special 330 - you must make very sure that no coro is still active on global destruction.
242 support for coroutines (like it does for threads). 331 very bad things might happen otherwise (usually segfaults).
243 - there is still a memleak on coroutine termination that I could not
244 identify. Could be as small as a single SV.
245 - this module is not well-tested.
246 - if variables or arguments "disappear" (become undef) or become
247 corrupted please contact the author so he cen iron out the
248 remaining bugs.
249 - this module is not thread-safe. You must only ever use this module from 332 - this module is not thread-safe. You should only ever use this module from
250 the same thread (this requirement might be loosened in the future to 333 the same thread (this requirement might be loosened in the future to
251 allow per-thread schedulers, but Coro::State does not yet allow this). 334 allow per-thread schedulers, but Coro::State does not yet allow this).
252 335
253=head1 SEE ALSO 336=head1 SEE ALSO
254 337

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