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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 1.42 by root, Tue Nov 6 20:37:20 2001 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$VERSION = 0.52;
42 42
43@EXPORT = qw(async cede schedule terminate current); 43@EXPORT = qw(async cede schedule terminate current);
44@EXPORT_OK = qw($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
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111}; 114};
112 115
113# this coroutine is necessary because a coroutine 116# this coroutine is necessary because a coroutine
114# cannot destroy itself. 117# cannot destroy itself.
115my @destroy; 118my @destroy;
119my $manager;
116my $manager = new Coro sub { 120$manager = new Coro sub {
117 while() { 121 while() {
118 delete ((pop @destroy)->{_coro_state}) while @destroy; 122 # by overwriting the state object with the manager we destroy it
123 # while still being able to schedule this coroutine (in case it has
124 # been readied multiple times. this is harmless since the manager
125 # can be called as many times as neccessary and will always
126 # remove itself from the runqueue
127 while (@destroy) {
128 my $coro = pop @destroy;
129 $coro->{status} ||= [];
130 $_->ready for @{delete $coro->{join} || []};
131 $coro->{_coro_state} = $manager->{_coro_state};
132 }
119 &schedule; 133 &schedule;
120 } 134 }
121}; 135};
122 136
123# static methods. not really. 137# static methods. not really.
… …
165ready queue and calls C<schedule>, which has the effect of giving up the 179ready queue and calls C<schedule>, which has the effect of giving up the
166current "timeslice" to other coroutines of the same or higher priority. 180current "timeslice" to other coroutines of the same or higher priority.
167 181
168=cut 182=cut
169 183
170=item terminate 184=item terminate [arg...]
171 185
172Terminates the current process. 186Terminates the current process.
173 187
174Future versions of this function will allow result arguments. 188Future versions of this function will allow result arguments.
175 189
176=cut 190=cut
177 191
178sub terminate { 192sub terminate {
193 $current->{status} = [@_];
179 $current->cancel; 194 $current->cancel;
180 &schedule; 195 &schedule;
181 die; # NORETURN 196 die; # NORETURN
182} 197}
183 198
… …
192=over 4 207=over 4
193 208
194=item new Coro \&sub [, @args...] 209=item new Coro \&sub [, @args...]
195 210
196Create a new process and return it. When the sub returns the process 211Create a new process and return it. When the sub returns the process
197automatically terminates. To start the process you must first put it into 212automatically terminates as if C<terminate> with the returned values were
213called. To make the process run you must first put it into the ready queue
198the ready queue by calling the ready method. 214by 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.
202 215
203=cut 216=cut
204 217
205sub _newcoro { 218sub _newcoro {
206 terminate &{+shift}; 219 terminate &{+shift};
… …
213 }, $class; 226 }, $class;
214} 227}
215 228
216=item $process->ready 229=item $process->ready
217 230
218Put the current process into the ready queue. 231Put the given process into the ready queue.
219 232
220=cut 233=cut
221 234
222=item $process->cancel 235=item $process->cancel
223 236
… …
226=cut 239=cut
227 240
228sub cancel { 241sub cancel {
229 push @destroy, $_[0]; 242 push @destroy, $_[0];
230 $manager->ready; 243 $manager->ready;
244 &schedule if $current == $_[0];
245}
246
247=item $process->join
248
249Wait until the coroutine terminates and return any values given to the
250C<terminate> function. C<join> can be called multiple times from multiple
251processes.
252
253=cut
254
255sub join {
256 my $self = shift;
257 unless ($self->{status}) {
258 push @{$self->{join}}, $current;
259 &schedule;
260 }
261 wantarray ? @{$self->{status}} : $self->{status}[0];
262}
263
264=item $oldprio = $process->prio($newprio)
265
266Sets (or gets, if the argument is missing) the priority of the
267process. Higher priority processes get run before lower priority
268processes. Priorities are smalled signed integer (currently -4 .. +3),
269that you can refer to using PRIO_xxx constants (use the import tag :prio
270to get then):
271
272 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
273 3 > 1 > 0 > -1 > -3 > -4
274
275 # set priority to HIGH
276 current->prio(PRIO_HIGH);
277
278The idle coroutine ($Coro::idle) always has a lower priority than any
279existing coroutine.
280
281Changing the priority of the current process will take effect immediately,
282but changing the priority of processes in the ready queue (but not
283running) will only take effect after the next schedule (of that
284process). This is a bug that will be fixed in some future version.
285
286=cut
287
288sub prio {
289 my $old = $_[0]{prio};
290 $_[0]{prio} = $_[1] if @_ > 1;
291 $old;
292}
293
294=item $newprio = $process->nice($change)
295
296Similar to C<prio>, but subtract the given value from the priority (i.e.
297higher values mean lower priority, just as in unix).
298
299=cut
300
301sub nice {
302 $_[0]{prio} -= $_[1];
303}
304
305=item $olddesc = $process->desc($newdesc)
306
307Sets (or gets in case the argument is missing) the description for this
308process. This is just a free-form string you can associate with a process.
309
310=cut
311
312sub desc {
313 my $old = $_[0]{desc};
314 $_[0]{desc} = $_[1] if @_ > 1;
315 $old;
231} 316}
232 317
233=back 318=back
234 319
235=cut 320=cut
236 321
2371; 3221;
238 323
239=head1 BUGS/LIMITATIONS 324=head1 BUGS/LIMITATIONS
240 325
241 - could be faster, especially when the core would introduce special 326 - you must make very sure that no coro is still active on global destruction.
242 support for coroutines (like it does for threads). 327 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 328 - 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 329 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). 330 allow per-thread schedulers, but Coro::State does not yet allow this).
252 331
253=head1 SEE ALSO 332=head1 SEE ALSO
254 333

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