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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 1.36 by root, Mon Sep 24 01:36:20 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 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$VERSION = 0.5;
48 44
49@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
50@EXPORT_OK = qw($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 = new Coro sub {
122 while() {
123 delete ((pop @destroy)->{_coro_state}) while @destroy;
124 &schedule;
125 }
126};
116 127
117# static methods. not really. 128# static methods. not really.
118 129
119=head2 STATIC METHODS 130=head2 STATIC METHODS
120 131
… …
138 149
139=cut 150=cut
140 151
141sub async(&@) { 152sub async(&@) {
142 my $pid = new Coro @_; 153 my $pid = new Coro @_;
154 $manager->ready; # this ensures that the stack is cloned from the manager
143 $pid->ready; 155 $pid->ready;
144 $pid; 156 $pid;
145} 157}
146 158
147=item schedule 159=item schedule
… …
150into the ready queue, so calling this function usually means you will 162into the ready queue, so calling this function usually means you will
151never be called again. 163never be called again.
152 164
153=cut 165=cut
154 166
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 167=item cede
164 168
165Yield to other processes. This function puts the current process into the 169"Cede" to other processes. This function puts the current process into the
166ready queue and calls C<schedule>. 170ready queue and calls C<schedule>, which has the effect of giving up the
171current "timeslice" to other coroutines of the same or higher priority.
167 172
168=cut 173=cut
169 174
170sub yield { 175=item terminate
176
177Terminates the current process.
178
179Future versions of this function will allow result arguments.
180
181=cut
182
183sub terminate {
171 $current->ready; 184 $current->cancel;
172 &schedule; 185 &schedule;
173} 186 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} 187}
188 188
189=back 189=back
190 190
191# dynamic methods 191# dynamic methods
… …
222 222
223Put the current process into the ready queue. 223Put the current process into the ready queue.
224 224
225=cut 225=cut
226 226
227sub ready { 227=item $process->cancel
228
229Like C<terminate>, but terminates the specified process instead.
230
231=cut
232
233sub cancel {
228 push @ready, $_[0]; 234 push @destroy, $_[0];
235 $manager->ready;
236 &schedule if $current == $_[0];
237}
238
239=item $oldprio = $process->prio($newprio)
240
241Sets the priority of the process. Higher priority processes get run before
242lower priority processes. Priorities are smalled signed integer (currently
243-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
244tag :prio to get then):
245
246 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
247 3 > 1 > 0 > -1 > -3 > -4
248
249 # set priority to HIGH
250 current->prio(PRIO_HIGH);
251
252The idle coroutine ($Coro::idle) always has a lower priority than any
253existing coroutine.
254
255Changing the priority of the current process will take effect immediately,
256but changing the priority of processes in the ready queue (but not
257running) will only take effect after the next schedule (of that
258process). This is a bug that will be fixed in some future version.
259
260=cut
261
262sub prio {
263 my $old = $_[0]{prio};
264 $_[0]{prio} = $_[1] if @_ > 1;
265 $old;
266}
267
268=item $newprio = $process->nice($change)
269
270Similar to C<prio>, but subtract the given value from the priority (i.e.
271higher values mean lower priority, just as in unix).
272
273=cut
274
275sub nice {
276 $_[0]{prio} -= $_[1];
229} 277}
230 278
231=back 279=back
232 280
233=cut 281=cut
234 282
2351; 2831;
236 284
237=head1 BUGS/LIMITATIONS 285=head1 BUGS/LIMITATIONS
238 286
239 - could be faster, especially when the core would introduce special 287 - you must make very sure that no coro is still active on global destruction.
240 support for coroutines (like it does for threads). 288 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 289 - 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 290 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). 291 allow per-thread schedulers, but Coro::State does not yet allow this).
250 292
251=head1 SEE ALSO 293=head1 SEE ALSO
252 294
253L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 295L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
254L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 296L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
297L<Coro::Handle>, L<Coro::Socket>.
255 298
256=head1 AUTHOR 299=head1 AUTHOR
257 300
258 Marc Lehmann <pcg@goof.com> 301 Marc Lehmann <pcg@goof.com>
259 http://www.goof.com/pcg/marc/ 302 http://www.goof.com/pcg/marc/

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