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Comparing Coro/Coro.pm (file contents):
Revision 1.20 by root, Sat Jul 21 18:21:45 2001 UTC vs.
Revision 1.52 by root, Tue May 27 00:26:34 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
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), that is, a coroutine has it's own callchain, it's 27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 28callchain, it's own set of lexicals and it's own set of perl's most
31variables. 29important global variables.
32 30
33=cut 31=cut
34 32
35package Coro; 33package Coro;
36 34
35no warnings qw(uninitialized);
36
37use Coro::State; 37use Coro::State;
38 38
39use base Exporter; 39use base Exporter;
40 40
41$VERSION = 0.10; 41$VERSION = 0.652;
42 42
43@EXPORT = qw(async yield schedule terminate current); 43@EXPORT = qw(async cede schedule terminate current);
44@EXPORT_OK = qw($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}
79
80=over 4
71 81
72=item $main 82=item $main
73 83
74This coroutine represents the main program. 84This coroutine represents the main program.
75 85
… …
103our $idle = new Coro sub { 113our $idle = new Coro sub {
104 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
105 exit(51); 115 exit(51);
106}; 116};
107 117
108# we really need priorities... 118# this coroutine is necessary because a coroutine
109my @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};
110 138
111# static methods. not really. 139# static methods. not really.
140
141=back
112 142
113=head2 STATIC METHODS 143=head2 STATIC METHODS
114 144
115Static methods are actually functions that operate on the current process only. 145Static methods are actually functions that operate on the current process only.
116 146
… …
132 162
133=cut 163=cut
134 164
135sub async(&@) { 165sub async(&@) {
136 my $pid = new Coro @_; 166 my $pid = new Coro @_;
167 $manager->ready; # this ensures that the stack is cloned from the manager
137 $pid->ready; 168 $pid->ready;
138 $pid; 169 $pid;
139} 170}
140 171
141=item schedule 172=item schedule
… …
144into the ready queue, so calling this function usually means you will 175into the ready queue, so calling this function usually means you will
145never be called again. 176never be called again.
146 177
147=cut 178=cut
148 179
149my $prev;
150
151sub schedule {
152 # should be done using priorities :(
153 ($prev, $current) = ($current, shift @ready || $idle);
154 Coro::State::transfer($prev, $current);
155}
156
157=item yield 180=item cede
158 181
159Yield to other processes. This function puts the current process into the 182"Cede" to other processes. This function puts the current process into the
160ready 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.
161 185
162=cut 186=cut
163 187
164sub 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} = [@_];
165 $current->ready; 198 $current->cancel;
166 &schedule; 199 &schedule;
167} 200 die; # NORETURN
168
169=item terminate
170
171Terminates the current process.
172
173Future versions of this function will allow result arguments.
174
175=cut
176
177sub terminate {
178 $current->{_results} = [@_];
179 &schedule;
180} 201}
181 202
182=back 203=back
183 204
184# dynamic methods 205# dynamic methods
… …
190=over 4 211=over 4
191 212
192=item new Coro \&sub [, @args...] 213=item new Coro \&sub [, @args...]
193 214
194Create 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
195automatically 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
196the ready queue by calling the ready method. 218by calling the ready method.
197
198The coderef you submit MUST NOT be a closure that refers to variables
199in an outer scope. This does NOT work. Pass arguments into it instead.
200 219
201=cut 220=cut
202 221
203sub _newcoro { 222sub _newcoro {
204 terminate &{+shift}; 223 terminate &{+shift};
… …
211 }, $class; 230 }, $class;
212} 231}
213 232
214=item $process->ready 233=item $process->ready
215 234
216Put the current process into the ready queue. 235Put the given process into the ready queue.
217 236
218=cut 237=cut
219 238
220sub ready { 239=item $process->cancel
240
241Like C<terminate>, but terminates the specified process instead.
242
243=cut
244
245sub cancel {
221 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;
222} 320}
223 321
224=back 322=back
225 323
226=cut 324=cut
227 325
2281; 3261;
229 327
230=head1 BUGS/LIMITATIONS 328=head1 BUGS/LIMITATIONS
231 329
232 - could be faster, especially when the core would introduce special 330 - you must make very sure that no coro is still active on global
233 support for coroutines (like it does for threads). 331 destruction. very bad things might happen otherwise (usually segfaults
234 - there is still a memleak on coroutine termination that I could not 332 or "panic: top_env").
235 identify. Could be as small as a single SV. 333
236 - this module is not well-tested.
237 - if variables or arguments "disappear" (become undef) or become
238 corrupted please contact the author so he cen iron out the
239 remaining bugs.
240 - this module is not thread-safe. You must only ever use this module from 334 - this module is not thread-safe. You should only ever use this module
241 the same thread (this requirement might be loosened in the future to 335 from the same thread (this requirement might be losened in the future
242 allow per-thread schedulers, but Coro::State does not yet allow this). 336 to allow per-thread schedulers, but Coro::State does not yet allow
337 this).
243 338
244=head1 SEE ALSO 339=head1 SEE ALSO
245 340
246L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 341L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
247L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 342L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
343L<Coro::Handle>, L<Coro::Socket>.
248 344
249=head1 AUTHOR 345=head1 AUTHOR
250 346
251 Marc Lehmann <pcg@goof.com> 347 Marc Lehmann <pcg@goof.com>
252 http://www.goof.com/pcg/marc/ 348 http://www.goof.com/pcg/marc/

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