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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 1.37 by root, Mon Sep 24 02:25:44 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 # by overwriting the state object with the manager we destroy it
124 # while still being able to schedule this coroutine (in case it has
125 # been readied multiple times. this is harmless since the manager
126 # can be called as many times as neccessary and will always
127 # remove itself from the runqueue
128 (pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy;
129 &schedule;
130 }
131};
116 132
117# static methods. not really. 133# static methods. not really.
118 134
119=head2 STATIC METHODS 135=head2 STATIC METHODS
120 136
… …
138 154
139=cut 155=cut
140 156
141sub async(&@) { 157sub async(&@) {
142 my $pid = new Coro @_; 158 my $pid = new Coro @_;
159 $manager->ready; # this ensures that the stack is cloned from the manager
143 $pid->ready; 160 $pid->ready;
144 $pid; 161 $pid;
145} 162}
146 163
147=item schedule 164=item schedule
… …
150into the ready queue, so calling this function usually means you will 167into the ready queue, so calling this function usually means you will
151never be called again. 168never be called again.
152 169
153=cut 170=cut
154 171
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 172=item cede
164 173
165Yield to other processes. This function puts the current process into the 174"Cede" to other processes. This function puts the current process into the
166ready queue and calls C<schedule>. 175ready queue and calls C<schedule>, which has the effect of giving up the
176current "timeslice" to other coroutines of the same or higher priority.
167 177
168=cut 178=cut
169 179
170sub yield { 180=item terminate
181
182Terminates the current process.
183
184Future versions of this function will allow result arguments.
185
186=cut
187
188sub terminate {
171 $current->ready; 189 $current->cancel;
172 &schedule; 190 &schedule;
173} 191 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} 192}
188 193
189=back 194=back
190 195
191# dynamic methods 196# dynamic methods
… …
222 227
223Put the current process into the ready queue. 228Put the current process into the ready queue.
224 229
225=cut 230=cut
226 231
227sub ready { 232=item $process->cancel
233
234Like C<terminate>, but terminates the specified process instead.
235
236=cut
237
238sub cancel {
228 push @ready, $_[0]; 239 push @destroy, $_[0];
240 $manager->ready;
241 &schedule if $current == $_[0];
242}
243
244=item $oldprio = $process->prio($newprio)
245
246Sets the priority of the process. Higher priority processes get run before
247lower priority processes. Priorities are smalled signed integer (currently
248-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
249tag :prio to get then):
250
251 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
252 3 > 1 > 0 > -1 > -3 > -4
253
254 # set priority to HIGH
255 current->prio(PRIO_HIGH);
256
257The idle coroutine ($Coro::idle) always has a lower priority than any
258existing coroutine.
259
260Changing the priority of the current process will take effect immediately,
261but changing the priority of processes in the ready queue (but not
262running) will only take effect after the next schedule (of that
263process). This is a bug that will be fixed in some future version.
264
265=cut
266
267sub prio {
268 my $old = $_[0]{prio};
269 $_[0]{prio} = $_[1] if @_ > 1;
270 $old;
271}
272
273=item $newprio = $process->nice($change)
274
275Similar to C<prio>, but subtract the given value from the priority (i.e.
276higher values mean lower priority, just as in unix).
277
278=cut
279
280sub nice {
281 $_[0]{prio} -= $_[1];
229} 282}
230 283
231=back 284=back
232 285
233=cut 286=cut
234 287
2351; 2881;
236 289
237=head1 BUGS/LIMITATIONS 290=head1 BUGS/LIMITATIONS
238 291
239 - could be faster, especially when the core would introduce special 292 - you must make very sure that no coro is still active on global destruction.
240 support for coroutines (like it does for threads). 293 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 294 - 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 295 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). 296 allow per-thread schedulers, but Coro::State does not yet allow this).
250 297
251=head1 SEE ALSO 298=head1 SEE ALSO
252 299
253L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 300L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
254L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 301L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
302L<Coro::Handle>, L<Coro::Socket>.
255 303
256=head1 AUTHOR 304=head1 AUTHOR
257 305
258 Marc Lehmann <pcg@goof.com> 306 Marc Lehmann <pcg@goof.com>
259 http://www.goof.com/pcg/marc/ 307 http://www.goof.com/pcg/marc/

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