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Comparing Coro/Coro.pm (file contents):
Revision 1.21 by root, Sun Jul 22 03:24:10 2001 UTC vs.
Revision 1.42 by root, Tue Nov 6 20:37:20 2001 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 28callchain, it's own set of lexicals and it's own set of perl's most
31variables. 29important global variables.
32
33WARNING: When using this module, make sure that, at program end, no
34coroutines are still running OR just call exit before falling off the
35end. The reason for this is that some coroutine of yours might have called
36into a C function, and falling off the end of main:: results in returning
37to that C function instead if to the main C interpreter.
38 30
39=cut 31=cut
40 32
41package Coro; 33package Coro;
42 34
35no warnings qw(uninitialized);
36
43use Coro::State; 37use Coro::State;
44 38
45use base Exporter; 39use base Exporter;
46 40
47$VERSION = 0.10; 41$VERSION = 0.52;
48 42
49@EXPORT = qw(async yield schedule terminate current); 43@EXPORT = qw(async cede schedule terminate current);
50@EXPORT_OK = qw($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}};
51 48
52{ 49{
53 my @async; 50 my @async;
51 my $init;
54 52
55 # this way of handling attributes simply is NOT scalable ;() 53 # this way of handling attributes simply is NOT scalable ;()
56 sub import { 54 sub import {
57 Coro->export_to_level(1, @_); 55 Coro->export_to_level(1, @_);
58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 56 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
60 my ($package, $ref) = (shift, shift); 58 my ($package, $ref) = (shift, shift);
61 my @attrs; 59 my @attrs;
62 for (@_) { 60 for (@_) {
63 if ($_ eq "Coro") { 61 if ($_ eq "Coro") {
64 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 }
65 } else { 70 } else {
66 push @attrs, $_; 71 push @attrs, $_;
67 } 72 }
68 } 73 }
69 return $old ? $old->($package, $ref, @attrs) : @attrs; 74 return $old ? $old->($package, $ref, @attrs) : @attrs;
70 }; 75 };
71 } 76 }
72 77
73 sub INIT {
74 &async(pop @async) while @async;
75 }
76} 78}
77 79
78=item $main 80=item $main
79 81
80This coroutine represents the main program. 82This coroutine represents the main program.
… …
109our $idle = new Coro sub { 111our $idle = new Coro sub {
110 print STDERR "FATAL: deadlock detected\n"; 112 print STDERR "FATAL: deadlock detected\n";
111 exit(51); 113 exit(51);
112}; 114};
113 115
114# we really need priorities... 116# this coroutine is necessary because a coroutine
115my @ready; # the ready queue. hehe, rather broken ;) 117# cannot destroy itself.
118my @destroy;
119my $manager;
120$manager = new Coro sub {
121 while() {
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 }
133 &schedule;
134 }
135};
116 136
117# static methods. not really. 137# static methods. not really.
118 138
119=head2 STATIC METHODS 139=head2 STATIC METHODS
120 140
… …
138 158
139=cut 159=cut
140 160
141sub async(&@) { 161sub async(&@) {
142 my $pid = new Coro @_; 162 my $pid = new Coro @_;
163 $manager->ready; # this ensures that the stack is cloned from the manager
143 $pid->ready; 164 $pid->ready;
144 $pid; 165 $pid;
145} 166}
146 167
147=item schedule 168=item schedule
… …
150into the ready queue, so calling this function usually means you will 171into the ready queue, so calling this function usually means you will
151never be called again. 172never be called again.
152 173
153=cut 174=cut
154 175
155my $prev;
156
157sub schedule {
158 # should be done using priorities :(
159 ($prev, $current) = ($current, shift @ready || $idle);
160 Coro::State::transfer($prev, $current);
161}
162
163=item yield 176=item cede
164 177
165Yield to other processes. This function puts the current process into the 178"Cede" to other processes. This function puts the current process into the
166ready queue and calls C<schedule>. 179ready queue and calls C<schedule>, which has the effect of giving up the
180current "timeslice" to other coroutines of the same or higher priority.
167 181
168=cut 182=cut
169 183
170sub yield { 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} = [@_];
171 $current->ready; 194 $current->cancel;
172 &schedule; 195 &schedule;
173} 196 die; # NORETURN
174
175=item terminate
176
177Terminates the current process.
178
179Future versions of this function will allow result arguments.
180
181=cut
182
183sub terminate {
184 $current->{_results} = [@_];
185 delete $current->{_coro_state};
186 &schedule;
187} 197}
188 198
189=back 199=back
190 200
191# dynamic methods 201# dynamic methods
… …
197=over 4 207=over 4
198 208
199=item new Coro \&sub [, @args...] 209=item new Coro \&sub [, @args...]
200 210
201Create 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
202automatically 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
203the ready queue by calling the ready method. 214by calling the ready method.
204
205The coderef you submit MUST NOT be a closure that refers to variables
206in an outer scope. This does NOT work. Pass arguments into it instead.
207 215
208=cut 216=cut
209 217
210sub _newcoro { 218sub _newcoro {
211 terminate &{+shift}; 219 terminate &{+shift};
… …
218 }, $class; 226 }, $class;
219} 227}
220 228
221=item $process->ready 229=item $process->ready
222 230
223Put the current process into the ready queue. 231Put the given process into the ready queue.
224 232
225=cut 233=cut
226 234
227sub ready { 235=item $process->cancel
236
237Like C<terminate>, but terminates the specified process instead.
238
239=cut
240
241sub cancel {
228 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;
229} 316}
230 317
231=back 318=back
232 319
233=cut 320=cut
234 321
2351; 3221;
236 323
237=head1 BUGS/LIMITATIONS 324=head1 BUGS/LIMITATIONS
238 325
239 - 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.
240 support for coroutines (like it does for threads). 327 very bad things might happen otherwise (usually segfaults).
241 - there is still a memleak on coroutine termination that I could not
242 identify. Could be as small as a single SV.
243 - this module is not well-tested.
244 - if variables or arguments "disappear" (become undef) or become
245 corrupted please contact the author so he cen iron out the
246 remaining bugs.
247 - 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
248 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
249 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).
250 331
251=head1 SEE ALSO 332=head1 SEE ALSO
252 333
253L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 334L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
254L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 335L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
336L<Coro::Handle>, L<Coro::Socket>.
255 337
256=head1 AUTHOR 338=head1 AUTHOR
257 339
258 Marc Lehmann <pcg@goof.com> 340 Marc Lehmann <pcg@goof.com>
259 http://www.goof.com/pcg/marc/ 341 http://www.goof.com/pcg/marc/

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