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Comparing Coro/Coro.pm (file contents):
Revision 1.19 by root, Sat Jul 21 03:44:06 2001 UTC vs.
Revision 1.53 by root, Tue May 27 01:15:26 2003 UTC

… …
14 14
15 sub some_func : Coro { 15 sub some_func : Coro {
16 # some more async code 16 # some more async code
17 } 17 }
18 18
19 yield; 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 25
26This module is still experimental, see the BUGS section below. 26In this module, coroutines are defined as "callchain + lexical variables
27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
27 30
28=cut 31=cut
29 32
30package Coro; 33package Coro;
31 34
35no warnings qw(uninitialized);
36
32use Coro::State; 37use Coro::State;
33 38
34use base Exporter; 39use base Exporter;
35 40
36$VERSION = 0.09; 41$VERSION = 0.7;
37 42
38@EXPORT = qw(async yield schedule terminate current); 43@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}};
40 48
41{ 49{
42 use subs 'async';
43
44 my @async; 50 my @async;
51 my $init;
45 52
46 # this way of handling attributes simply is NOT scalable ;() 53 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 54 sub import {
48 Coro->export_to_level(1, @_); 55 Coro->export_to_level(1, @_);
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 56 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
51 my ($package, $ref) = (shift, shift); 58 my ($package, $ref) = (shift, shift);
52 my @attrs; 59 my @attrs;
53 for (@_) { 60 for (@_) {
54 if ($_ eq "Coro") { 61 if ($_ eq "Coro") {
55 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 }
56 } else { 70 } else {
57 push @attrs, $_; 71 push @attrs, $_;
58 } 72 }
59 } 73 }
60 return $old ? $old->($package, $ref, @attrs) : @attrs; 74 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 75 };
62 } 76 }
63 77
64 sub INIT {
65 async pop @async while @async;
66 }
67} 78}
79
80=over 4
68 81
69=item $main 82=item $main
70 83
71This coroutine represents the main program. 84This coroutine represents the main program.
72 85
… …
100our $idle = new Coro sub { 113our $idle = new Coro sub {
101 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
102 exit(51); 115 exit(51);
103}; 116};
104 117
105# we really need priorities... 118# this coroutine is necessary because a coroutine
106my @ready; # the ready queue. hehe, rather broken ;) 119# cannot destroy itself.
120my @destroy;
121my $manager;
122$manager = new Coro sub {
123 while() {
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 }
135 &schedule;
136 }
137};
107 138
108# static methods. not really. 139# static methods. not really.
140
141=back
109 142
110=head2 STATIC METHODS 143=head2 STATIC METHODS
111 144
112Static methods are actually functions that operate on the current process only. 145Static methods are actually functions that operate on the current process only.
113 146
… …
129 162
130=cut 163=cut
131 164
132sub async(&@) { 165sub async(&@) {
133 my $pid = new Coro @_; 166 my $pid = new Coro @_;
167 $manager->ready; # this ensures that the stack is cloned from the manager
134 $pid->ready; 168 $pid->ready;
135 $pid; 169 $pid;
136} 170}
137 171
138=item schedule 172=item schedule
… …
141into the ready queue, so calling this function usually means you will 175into the ready queue, so calling this function usually means you will
142never be called again. 176never be called again.
143 177
144=cut 178=cut
145 179
146my $prev;
147
148sub schedule {
149 # should be done using priorities :(
150 ($prev, $current) = ($current, shift @ready || $idle);
151 Coro::State::transfer($prev, $current);
152}
153
154=item yield 180=item cede
155 181
156Yield to other processes. This function puts the current process into the 182"Cede" to other processes. This function puts the current process into the
157ready queue and calls C<schedule>. 183ready queue and calls C<schedule>, which has the effect of giving up the
184current "timeslice" to other coroutines of the same or higher priority.
158 185
159=cut 186=cut
160 187
161sub yield { 188=item terminate [arg...]
189
190Terminates the current process.
191
192Future versions of this function will allow result arguments.
193
194=cut
195
196sub terminate {
197 $current->{status} = [@_];
162 $current->ready; 198 $current->cancel;
163 &schedule; 199 &schedule;
164} 200 die; # NORETURN
165
166=item terminate
167
168Terminates the current process.
169
170Future versions of this function will allow result arguments.
171
172=cut
173
174sub terminate {
175 $current->{_results} = [@_];
176 &schedule;
177} 201}
178 202
179=back 203=back
180 204
181# dynamic methods 205# dynamic methods
… …
187=over 4 211=over 4
188 212
189=item new Coro \&sub [, @args...] 213=item new Coro \&sub [, @args...]
190 214
191Create 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
192automatically 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
193the ready queue by calling the ready method. 218by calling the ready method.
194
195The coderef you submit MUST NOT be a closure that refers to variables
196in an outer scope. This does NOT work. Pass arguments into it instead.
197 219
198=cut 220=cut
199 221
200sub _newcoro { 222sub _newcoro {
201 terminate &{+shift}; 223 terminate &{+shift};
… …
208 }, $class; 230 }, $class;
209} 231}
210 232
211=item $process->ready 233=item $process->ready
212 234
213Put the current process into the ready queue. 235Put the given process into the ready queue.
214 236
215=cut 237=cut
216 238
217sub ready { 239=item $process->cancel
240
241Like C<terminate>, but terminates the specified process instead.
242
243=cut
244
245sub cancel {
218 push @ready, $_[0]; 246 push @destroy, $_[0];
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 small signed integers (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;
219} 320}
220 321
221=back 322=back
222 323
223=cut 324=cut
224 325
2251; 3261;
226 327
227=head1 BUGS/LIMITATIONS 328=head1 BUGS/LIMITATIONS
228 329
229 - could be faster, especially when the core would introduce special 330 - you must make very sure that no coro is still active on global
230 support for coroutines (like it does for threads). 331 destruction. very bad things might happen otherwise (usually segfaults).
231 - there is still a memleak on coroutine termination that I could not 332
232 identify. Could be as small as a single SV.
233 - this module is not well-tested.
234 - if variables or arguments "disappear" (become undef) or become
235 corrupted please contact the author so he cen iron out the
236 remaining bugs.
237 - this module is not thread-safe. You must only ever use this module from 333 - this module is not thread-safe. You should only ever use this module
238 the same thread (this requirement might be loosened in the future to 334 from the same thread (this requirement might be losened in the future
239 allow per-thread schedulers, but Coro::Satte does not yet allow this). 335 to allow per-thread schedulers, but Coro::State does not yet allow
336 this).
240 337
241=head1 SEE ALSO 338=head1 SEE ALSO
242 339
243L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 340L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
244L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 341L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
342L<Coro::Handle>, L<Coro::Socket>.
245 343
246=head1 AUTHOR 344=head1 AUTHOR
247 345
248 Marc Lehmann <pcg@goof.com> 346 Marc Lehmann <pcg@goof.com>
249 http://www.goof.com/pcg/marc/ 347 http://www.goof.com/pcg/marc/

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