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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 1.40 by root, Sun Oct 28 17:00:05 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
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
28=cut 33=cut
29 34
30package Coro; 35package Coro;
31 36
37no warnings qw(uninitialized);
38
32use Coro::State; 39use Coro::State;
33 40
34use base Exporter; 41use base Exporter;
35 42
36$VERSION = 0.09; 43$VERSION = 0.51;
37 44
38@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}};
40 50
41{ 51{
42 use subs 'async';
43
44 my @async; 52 my @async;
53 my $init;
45 54
46 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 56 sub import {
48 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
51 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
52 my @attrs; 61 my @attrs;
53 for (@_) { 62 for (@_) {
54 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
55 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 }
56 } else { 72 } else {
57 push @attrs, $_; 73 push @attrs, $_;
58 } 74 }
59 } 75 }
60 return $old ? $old->($package, $ref, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 77 };
62 } 78 }
63 79
64 sub INIT {
65 async pop @async while @async;
66 }
67} 80}
68 81
69=item $main 82=item $main
70 83
71This coroutine represents the main program. 84This coroutine represents the main program.
… …
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.
109 140
110=head2 STATIC METHODS 141=head2 STATIC METHODS
111 142
… …
129 160
130=cut 161=cut
131 162
132sub async(&@) { 163sub async(&@) {
133 my $pid = new Coro @_; 164 my $pid = new Coro @_;
165 $manager->ready; # this ensures that the stack is cloned from the manager
134 $pid->ready; 166 $pid->ready;
135 $pid; 167 $pid;
136} 168}
137 169
138=item schedule 170=item schedule
… …
141into the ready queue, so calling this function usually means you will 173into the ready queue, so calling this function usually means you will
142never be called again. 174never be called again.
143 175
144=cut 176=cut
145 177
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 178=item cede
155 179
156Yield to other processes. This function puts the current process into the 180"Cede" to other processes. This function puts the current process into the
157ready 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.
158 183
159=cut 184=cut
160 185
161sub 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} = [@_];
162 $current->ready; 196 $current->cancel;
163 &schedule; 197 &schedule;
164} 198 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} 199}
178 200
179=back 201=back
180 202
181# dynamic methods 203# dynamic methods
… …
187=over 4 209=over 4
188 210
189=item new Coro \&sub [, @args...] 211=item new Coro \&sub [, @args...]
190 212
191Create 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
192automatically terminates. To start the process you must first put it into 214automatically terminates as if C<terminate> with the returned values were
193the ready queue by calling the ready method. 215called. To start the process you must first put it into the ready queue by
216calling the ready method.
194 217
195The coderef you submit MUST NOT be a closure that refers to variables 218The 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. 219in an outer scope. This does NOT work. Pass arguments into it instead.
197 220
198=cut 221=cut
… …
208 }, $class; 231 }, $class;
209} 232}
210 233
211=item $process->ready 234=item $process->ready
212 235
213Put the current process into the ready queue. 236Put the given process into the ready queue.
214 237
215=cut 238=cut
216 239
217sub ready { 240=item $process->cancel
241
242Like C<terminate>, but terminates the specified process instead.
243
244=cut
245
246sub cancel {
218 push @ready, $_[0]; 247 push @destroy, $_[0];
248 $manager->ready;
249 &schedule if $current == $_[0];
250}
251
252=item $process->join
253
254Wait until the coroutine terminates and return any values given to the
255C<terminate> function. C<join> can be called multiple times from multiple
256processes.
257
258=cut
259
260sub join {
261 my $self = shift;
262 unless ($self->{status}) {
263 push @{$self->{join}}, $current;
264 &schedule;
265 }
266 wantarray ? @{$self->{status}} : $self->{status}[0];
267}
268
269=item $oldprio = $process->prio($newprio)
270
271Sets the priority of the process. Higher priority processes get run before
272lower priority processes. Priorities are smalled signed integer (currently
273-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
274tag :prio to 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];
219} 307}
220 308
221=back 309=back
222 310
223=cut 311=cut
224 312
2251; 3131;
226 314
227=head1 BUGS/LIMITATIONS 315=head1 BUGS/LIMITATIONS
228 316
229 - could be faster, especially when the core would introduce special 317 - you must make very sure that no coro is still active on global destruction.
230 support for coroutines (like it does for threads). 318 very bad things might happen otherwise (usually segfaults).
231 - there is still a memleak on coroutine termination that I could not
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 319 - this module is not thread-safe. You must only ever use this module from
238 the same thread (this requirement might be loosened in the future to 320 the same thread (this requirement might be loosened in the future to
239 allow per-thread schedulers, but Coro::Satte does not yet allow this). 321 allow per-thread schedulers, but Coro::State does not yet allow this).
240 322
241=head1 SEE ALSO 323=head1 SEE ALSO
242 324
243L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 325L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
244L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 326L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
327L<Coro::Handle>, L<Coro::Socket>.
245 328
246=head1 AUTHOR 329=head1 AUTHOR
247 330
248 Marc Lehmann <pcg@goof.com> 331 Marc Lehmann <pcg@goof.com>
249 http://www.goof.com/pcg/marc/ 332 http://www.goof.com/pcg/marc/

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