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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 1.41 by root, Tue Nov 6 20:34:09 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 25
26This module is still experimental, see the BUGS section below. 26This module is still experimental, see the BUGS section below.
27 27
28In this module, coroutines are defined as "callchain + lexical variables 28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W), that is, a coroutine has it's own callchain, it's 29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 30callchain, it's own set of lexicals and it's own set of perl's most
31variables. 31important global variables.
32
33WARNING: When using this module, make sure that, at program end, no
34coroutines are still running OR just call exit before falling off the
35end. The reason for this is that some coroutine of yours might have called
36into a C function, and falling off the end of main:: results in returning
37to that C function instead if to the main C interpreter.
38 32
39=cut 33=cut
40 34
41package Coro; 35package Coro;
42 36
37no warnings qw(uninitialized);
38
43use Coro::State; 39use Coro::State;
44 40
45use base Exporter; 41use base Exporter;
46 42
47$VERSION = 0.10; 43$VERSION = 0.52;
48 44
49@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
50@EXPORT_OK = qw($current); 46%EXPORT_TAGS = (
47 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
48);
49@EXPORT_OK = @{$EXPORT_TAGS{prio}};
51 50
52{ 51{
53 my @async; 52 my @async;
53 my $init;
54 54
55 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
56 sub import { 56 sub import {
57 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
60 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
61 my @attrs; 61 my @attrs;
62 for (@_) { 62 for (@_) {
63 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
64 push @async, $ref; 64 push @async, $ref;
65 unless ($init++) {
66 eval q{
67 sub INIT {
68 &async(pop @async) while @async;
69 }
70 };
71 }
65 } else { 72 } else {
66 push @attrs, $_; 73 push @attrs, $_;
67 } 74 }
68 } 75 }
69 return $old ? $old->($package, $ref, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
70 }; 77 };
71 } 78 }
72 79
73 sub INIT {
74 &async(pop @async) while @async;
75 }
76} 80}
77 81
78=item $main 82=item $main
79 83
80This coroutine represents the main program. 84This coroutine represents the main program.
… …
109our $idle = new Coro sub { 113our $idle = new Coro sub {
110 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
111 exit(51); 115 exit(51);
112}; 116};
113 117
114# we really need priorities... 118# this coroutine is necessary because a coroutine
115my @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};
116 138
117# static methods. not really. 139# static methods. not really.
118 140
119=head2 STATIC METHODS 141=head2 STATIC METHODS
120 142
… …
138 160
139=cut 161=cut
140 162
141sub async(&@) { 163sub async(&@) {
142 my $pid = new Coro @_; 164 my $pid = new Coro @_;
165 $manager->ready; # this ensures that the stack is cloned from the manager
143 $pid->ready; 166 $pid->ready;
144 $pid; 167 $pid;
145} 168}
146 169
147=item schedule 170=item schedule
… …
150into the ready queue, so calling this function usually means you will 173into the ready queue, so calling this function usually means you will
151never be called again. 174never be called again.
152 175
153=cut 176=cut
154 177
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 178=item cede
164 179
165Yield to other processes. This function puts the current process into the 180"Cede" to other processes. This function puts the current process into the
166ready queue and calls C<schedule>. 181ready queue and calls C<schedule>, which has the effect of giving up the
182current "timeslice" to other coroutines of the same or higher priority.
167 183
168=cut 184=cut
169 185
170sub yield { 186=item terminate [arg...]
187
188Terminates the current process.
189
190Future versions of this function will allow result arguments.
191
192=cut
193
194sub terminate {
195 $current->{status} = [@_];
171 $current->ready; 196 $current->cancel;
172 &schedule; 197 &schedule;
173} 198 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} 199}
188 200
189=back 201=back
190 202
191# dynamic methods 203# dynamic methods
… …
197=over 4 209=over 4
198 210
199=item new Coro \&sub [, @args...] 211=item new Coro \&sub [, @args...]
200 212
201Create a new process and return it. When the sub returns the process 213Create a new process and return it. When the sub returns the process
202automatically terminates. To start the process you must first put it into 214automatically terminates as if C<terminate> with the returned values were
215called. To make the process run you must first put it into the ready queue
203the ready queue by calling the ready method. 216by 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.
207 217
208=cut 218=cut
209 219
210sub _newcoro { 220sub _newcoro {
211 terminate &{+shift}; 221 terminate &{+shift};
… …
218 }, $class; 228 }, $class;
219} 229}
220 230
221=item $process->ready 231=item $process->ready
222 232
223Put the current process into the ready queue. 233Put the given process into the ready queue.
224 234
225=cut 235=cut
226 236
227sub ready { 237=item $process->cancel
238
239Like C<terminate>, but terminates the specified process instead.
240
241=cut
242
243sub cancel {
228 push @ready, $_[0]; 244 push @destroy, $_[0];
245 $manager->ready;
246 &schedule if $current == $_[0];
247}
248
249=item $process->join
250
251Wait until the coroutine terminates and return any values given to the
252C<terminate> function. C<join> can be called multiple times from multiple
253processes.
254
255=cut
256
257sub join {
258 my $self = shift;
259 unless ($self->{status}) {
260 push @{$self->{join}}, $current;
261 &schedule;
262 }
263 wantarray ? @{$self->{status}} : $self->{status}[0];
264}
265
266=item $oldprio = $process->prio($newprio)
267
268Sets (or gets, if the argument is missing) the priority of the
269process. Higher priority processes get run before lower priority
270processes. Priorities are smalled signed integer (currently -4 .. +3),
271that you can refer to using PRIO_xxx constants (use the import tag :prio
272to get then):
273
274 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
275 3 > 1 > 0 > -1 > -3 > -4
276
277 # set priority to HIGH
278 current->prio(PRIO_HIGH);
279
280The idle coroutine ($Coro::idle) always has a lower priority than any
281existing coroutine.
282
283Changing the priority of the current process will take effect immediately,
284but changing the priority of processes in the ready queue (but not
285running) will only take effect after the next schedule (of that
286process). This is a bug that will be fixed in some future version.
287
288=cut
289
290sub prio {
291 my $old = $_[0]{prio};
292 $_[0]{prio} = $_[1] if @_ > 1;
293 $old;
294}
295
296=item $newprio = $process->nice($change)
297
298Similar to C<prio>, but subtract the given value from the priority (i.e.
299higher values mean lower priority, just as in unix).
300
301=cut
302
303sub nice {
304 $_[0]{prio} -= $_[1];
305}
306
307=item $olddesc = $process->desc($newdesc)
308
309Sets (or gets in case the argument is missing) the description for this
310process. This is just a free-form string you can associate with a process.
311
312=cut
313
314sub desc {
315 my $old = $_[0]{desc};
316 $_[0]{desc} = $_[1] if @_ > 1;
317 $old;
229} 318}
230 319
231=back 320=back
232 321
233=cut 322=cut
234 323
2351; 3241;
236 325
237=head1 BUGS/LIMITATIONS 326=head1 BUGS/LIMITATIONS
238 327
239 - could be faster, especially when the core would introduce special 328 - you must make very sure that no coro is still active on global destruction.
240 support for coroutines (like it does for threads). 329 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 330 - this module is not thread-safe. You must only ever use this module from
248 the same thread (this requirement might be loosened in the future to 331 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). 332 allow per-thread schedulers, but Coro::State does not yet allow this).
250 333
251=head1 SEE ALSO 334=head1 SEE ALSO
252 335
253L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 336L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
254L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 337L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
338L<Coro::Handle>, L<Coro::Socket>.
255 339
256=head1 AUTHOR 340=head1 AUTHOR
257 341
258 Marc Lehmann <pcg@goof.com> 342 Marc Lehmann <pcg@goof.com>
259 http://www.goof.com/pcg/marc/ 343 http://www.goof.com/pcg/marc/

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