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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 1.35 by root, Mon Sep 24 00:16:30 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 30callchain, it's own set of lexicals and it's own set of perl's most
31variables. 31important global variables.
32
33WARNING: When using this module, make sure that, at program end, no
34coroutines are still running OR just call exit before falling off the
35end. The reason for this is that some coroutine of yours might have called
36into a C function, and falling off the end of main:: results in returning
37to that C function instead if to the main C interpreter.
38 32
39=cut 33=cut
40 34
41package Coro; 35package Coro;
42 36
43use Coro::State; 37use Coro::State;
44 38
45use base Exporter; 39use base Exporter;
46 40
47$VERSION = 0.10; 41$VERSION = 0.5;
48 42
49@EXPORT = qw(async yield schedule terminate current); 43@EXPORT = qw(async cede schedule terminate current);
50@EXPORT_OK = qw($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 = new Coro sub {
120 while() {
121 delete ((pop @destroy)->{_coro_state}) while @destroy;
122 &schedule;
123 }
124};
116 125
117# static methods. not really. 126# static methods. not really.
118 127
119=head2 STATIC METHODS 128=head2 STATIC METHODS
120 129
… …
138 147
139=cut 148=cut
140 149
141sub async(&@) { 150sub async(&@) {
142 my $pid = new Coro @_; 151 my $pid = new Coro @_;
152 $manager->ready; # this ensures that the stack is cloned from the manager
143 $pid->ready; 153 $pid->ready;
144 $pid; 154 $pid;
145} 155}
146 156
147=item schedule 157=item schedule
… …
150into the ready queue, so calling this function usually means you will 160into the ready queue, so calling this function usually means you will
151never be called again. 161never be called again.
152 162
153=cut 163=cut
154 164
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 165=item cede
164 166
165Yield to other processes. This function puts the current process into the 167"Cede" to other processes. This function puts the current process into the
166ready queue and calls C<schedule>. 168ready queue and calls C<schedule>, which has the effect of giving up the
169current "timeslice" to other coroutines of the same or higher priority.
167 170
168=cut 171=cut
169 172
170sub yield { 173=item terminate
174
175Terminates the current process.
176
177Future versions of this function will allow result arguments.
178
179=cut
180
181sub terminate {
171 $current->ready; 182 $current->cancel;
172 &schedule; 183 &schedule;
173} 184 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} 185}
188 186
189=back 187=back
190 188
191# dynamic methods 189# dynamic methods
… …
222 220
223Put the current process into the ready queue. 221Put the current process into the ready queue.
224 222
225=cut 223=cut
226 224
227sub ready { 225=item $process->cancel
226
227Like C<terminate>, but terminates the specified process instead.
228
229=cut
230
231sub cancel {
228 push @ready, $_[0]; 232 push @destroy, $_[0];
233 $manager->ready;
234 &schedule if $current == $_[0];
235}
236
237=item $oldprio = $process->prio($newprio)
238
239Sets the priority of the process. Higher priority processes get run before
240lower priority processes. Priorities are smalled signed integer (currently
241-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
242tag :prio to get then):
243
244 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
245 3 > 1 > 0 > -1 > -3 > -4
246
247 # set priority to HIGH
248 current->prio(PRIO_HIGH);
249
250The idle coroutine ($Coro::idle) always has a lower priority than any
251existing coroutine.
252
253Changing the priority of the current process will take effect immediately,
254but changing the priority of processes in the ready queue (but not
255running) will only take effect after the next schedule (of that
256process). This is a bug that will be fixed in some future version.
257
258=cut
259
260sub prio {
261 my $old = $_[0]{prio};
262 $_[0]{prio} = $_[1] if @_ > 1;
263 $old;
264}
265
266=item $newprio = $process->nice($change)
267
268Similar to C<prio>, but subtract the given value from the priority (i.e.
269higher values mean lower priority, just as in unix).
270
271=cut
272
273sub nice {
274 $_[0]{prio} -= $_[1];
229} 275}
230 276
231=back 277=back
232 278
233=cut 279=cut
234 280
2351; 2811;
236 282
237=head1 BUGS/LIMITATIONS 283=head1 BUGS/LIMITATIONS
238 284
239 - could be faster, especially when the core would introduce special 285 - you must make very sure that no coro is still active on global destruction.
240 support for coroutines (like it does for threads). 286 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 287 - 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 288 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). 289 allow per-thread schedulers, but Coro::State does not yet allow this).
250 290
251=head1 SEE ALSO 291=head1 SEE ALSO
252 292
253L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 293L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
254L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 294L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
295L<Coro::Handle>, L<Coro::Socket>.
255 296
256=head1 AUTHOR 297=head1 AUTHOR
257 298
258 Marc Lehmann <pcg@goof.com> 299 Marc Lehmann <pcg@goof.com>
259 http://www.goof.com/pcg/marc/ 300 http://www.goof.com/pcg/marc/

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