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Comparing Coro/Coro.pm (file contents):
Revision 1.25 by root, Wed Jul 25 21:12:57 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 = 0.12; 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;
51 my $init;
48 52
49 # this way of handling attributes simply is NOT scalable ;() 53 # this way of handling attributes simply is NOT scalable ;()
50 sub import { 54 sub import {
51 Coro->export_to_level(1, @_); 55 Coro->export_to_level(1, @_);
52 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 56 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
54 my ($package, $ref) = (shift, shift); 58 my ($package, $ref) = (shift, shift);
55 my @attrs; 59 my @attrs;
56 for (@_) { 60 for (@_) {
57 if ($_ eq "Coro") { 61 if ($_ eq "Coro") {
58 push @async, $ref; 62 push @async, $ref;
63 unless ($init++) {
64 eval q{
65 sub INIT {
66 &async(pop @async) while @async;
67 }
68 };
69 }
59 } else { 70 } else {
60 push @attrs, $_; 71 push @attrs, $_;
61 } 72 }
62 } 73 }
63 return $old ? $old->($package, $ref, @attrs) : @attrs; 74 return $old ? $old->($package, $ref, @attrs) : @attrs;
64 }; 75 };
65 } 76 }
66 77
67 sub INIT {
68 &async(pop @async) while @async;
69 }
70} 78}
71 79
72=item $main 80=item $main
73 81
74This coroutine represents the main program. 82This coroutine represents the main program.
… …
106}; 114};
107 115
108# this coroutine is necessary because a coroutine 116# this coroutine is necessary because a coroutine
109# cannot destroy itself. 117# cannot destroy itself.
110my @destroy; 118my @destroy;
119my $manager;
111my $manager = new Coro sub { 120$manager = new Coro sub {
112 while() { 121 while() {
113 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 }
114 &schedule; 133 &schedule;
115 } 134 }
116}; 135};
117
118# we really need priorities...
119my @ready; # the ready queue. hehe, rather broken ;)
120 136
121# static methods. not really. 137# static methods. not really.
122 138
123=head2 STATIC METHODS 139=head2 STATIC METHODS
124 140
… …
155into the ready queue, so calling this function usually means you will 171into the ready queue, so calling this function usually means you will
156never be called again. 172never be called again.
157 173
158=cut 174=cut
159 175
160my $prev;
161
162sub schedule {
163 # should be done using priorities :(
164 ($prev, $current) = ($current, shift @ready || $idle);
165 Coro::State::transfer($prev, $current);
166}
167
168=item cede 176=item cede
169 177
170"Cede" to other processes. This function puts the current process into the 178"Cede" to other processes. This function puts the current process into the
171ready 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
172current "timeslice" to other coroutines of the same or higher priority. 180current "timeslice" to other coroutines of the same or higher priority.
173 181
174=cut 182=cut
175 183
176sub cede { 184=item terminate [arg...]
185
186Terminates the current process.
187
188Future versions of this function will allow result arguments.
189
190=cut
191
192sub terminate {
193 $current->{status} = [@_];
177 $current->ready; 194 $current->cancel;
178 &schedule; 195 &schedule;
179}
180
181=item terminate
182
183Terminates the current process.
184
185Future versions of this function will allow result arguments.
186
187=cut
188
189sub terminate {
190 push @destroy, $current;
191 $manager->ready;
192 &schedule;
193 # NORETURN 196 die; # NORETURN
194} 197}
195 198
196=back 199=back
197 200
198# dynamic methods 201# dynamic methods
… …
204=over 4 207=over 4
205 208
206=item new Coro \&sub [, @args...] 209=item new Coro \&sub [, @args...]
207 210
208Create 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
209automatically 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
210the ready queue by calling the ready method. 214by calling the ready method.
211
212The coderef you submit MUST NOT be a closure that refers to variables
213in an outer scope. This does NOT work. Pass arguments into it instead.
214 215
215=cut 216=cut
216 217
217sub _newcoro { 218sub _newcoro {
218 terminate &{+shift}; 219 terminate &{+shift};
… …
225 }, $class; 226 }, $class;
226} 227}
227 228
228=item $process->ready 229=item $process->ready
229 230
230Put the current process into the ready queue. 231Put the given process into the ready queue.
231 232
232=cut 233=cut
233 234
234sub ready { 235=item $process->cancel
236
237Like C<terminate>, but terminates the specified process instead.
238
239=cut
240
241sub cancel {
235 push @ready, $_[0]; 242 push @destroy, $_[0];
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;
236} 316}
237 317
238=back 318=back
239 319
240=cut 320=cut
241 321
2421; 3221;
243 323
244=head1 BUGS/LIMITATIONS 324=head1 BUGS/LIMITATIONS
245 325
246 - 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.
247 support for coroutines (like it does for threads). 327 very bad things might happen otherwise (usually segfaults).
248 - there is still a memleak on coroutine termination that I could not
249 identify. Could be as small as a single SV.
250 - this module is not well-tested.
251 - if variables or arguments "disappear" (become undef) or become
252 corrupted please contact the author so he cen iron out the
253 remaining bugs.
254 - 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
255 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
256 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).
257 331
258=head1 SEE ALSO 332=head1 SEE ALSO
259 333
260L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 334L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
261L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>, 335L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
262L<Coro::L<Coro::Handle>, L<Coro::Socket>. 336L<Coro::Handle>, L<Coro::Socket>.
263 337
264=head1 AUTHOR 338=head1 AUTHOR
265 339
266 Marc Lehmann <pcg@goof.com> 340 Marc Lehmann <pcg@goof.com>
267 http://www.goof.com/pcg/marc/ 341 http://www.goof.com/pcg/marc/

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