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Comparing Coro/Coro.pm (file contents):
Revision 1.20 by root, Sat Jul 21 18:21:45 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 30callchain, it's own set of lexicals and it's own set of perl's most
31variables. 31important global variables.
32 32
33=cut 33=cut
34 34
35package Coro; 35package Coro;
36 36
37no warnings qw(uninitialized);
38
37use Coro::State; 39use Coro::State;
38 40
39use base Exporter; 41use base Exporter;
40 42
41$VERSION = 0.10; 43$VERSION = 0.5;
42 44
43@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
44@EXPORT_OK = qw($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}};
45 50
46{ 51{
47 my @async; 52 my @async;
53 my $init;
48 54
49 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
50 sub import { 56 sub import {
51 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
52 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
54 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
55 my @attrs; 61 my @attrs;
56 for (@_) { 62 for (@_) {
57 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
58 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 }
59 } else { 72 } else {
60 push @attrs, $_; 73 push @attrs, $_;
61 } 74 }
62 } 75 }
63 return $old ? $old->($package, $ref, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
64 }; 77 };
65 } 78 }
66 79
67 sub INIT {
68 &async(pop @async) while @async;
69 }
70} 80}
71 81
72=item $main 82=item $main
73 83
74This coroutine represents the main program. 84This coroutine represents the main program.
… …
103our $idle = new Coro sub { 113our $idle = new Coro sub {
104 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
105 exit(51); 115 exit(51);
106}; 116};
107 117
108# we really need priorities... 118# this coroutine is necessary because a coroutine
109my @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};
110 132
111# static methods. not really. 133# static methods. not really.
112 134
113=head2 STATIC METHODS 135=head2 STATIC METHODS
114 136
… …
132 154
133=cut 155=cut
134 156
135sub async(&@) { 157sub async(&@) {
136 my $pid = new Coro @_; 158 my $pid = new Coro @_;
159 $manager->ready; # this ensures that the stack is cloned from the manager
137 $pid->ready; 160 $pid->ready;
138 $pid; 161 $pid;
139} 162}
140 163
141=item schedule 164=item schedule
… …
144into the ready queue, so calling this function usually means you will 167into the ready queue, so calling this function usually means you will
145never be called again. 168never be called again.
146 169
147=cut 170=cut
148 171
149my $prev;
150
151sub schedule {
152 # should be done using priorities :(
153 ($prev, $current) = ($current, shift @ready || $idle);
154 Coro::State::transfer($prev, $current);
155}
156
157=item yield 172=item cede
158 173
159Yield to other processes. This function puts the current process into the 174"Cede" to other processes. This function puts the current process into the
160ready 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.
161 177
162=cut 178=cut
163 179
164sub 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 {
165 $current->ready; 189 $current->cancel;
166 &schedule; 190 &schedule;
167} 191 die; # NORETURN
168
169=item terminate
170
171Terminates the current process.
172
173Future versions of this function will allow result arguments.
174
175=cut
176
177sub terminate {
178 $current->{_results} = [@_];
179 &schedule;
180} 192}
181 193
182=back 194=back
183 195
184# dynamic methods 196# dynamic methods
… …
215 227
216Put the current process into the ready queue. 228Put the current process into the ready queue.
217 229
218=cut 230=cut
219 231
220sub ready { 232=item $process->cancel
233
234Like C<terminate>, but terminates the specified process instead.
235
236=cut
237
238sub cancel {
221 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];
222} 282}
223 283
224=back 284=back
225 285
226=cut 286=cut
227 287
2281; 2881;
229 289
230=head1 BUGS/LIMITATIONS 290=head1 BUGS/LIMITATIONS
231 291
232 - 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.
233 support for coroutines (like it does for threads). 293 very bad things might happen otherwise (usually segfaults).
234 - there is still a memleak on coroutine termination that I could not
235 identify. Could be as small as a single SV.
236 - this module is not well-tested.
237 - if variables or arguments "disappear" (become undef) or become
238 corrupted please contact the author so he cen iron out the
239 remaining bugs.
240 - 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
241 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
242 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).
243 297
244=head1 SEE ALSO 298=head1 SEE ALSO
245 299
246L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 300L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
247L<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>.
248 303
249=head1 AUTHOR 304=head1 AUTHOR
250 305
251 Marc Lehmann <pcg@goof.com> 306 Marc Lehmann <pcg@goof.com>
252 http://www.goof.com/pcg/marc/ 307 http://www.goof.com/pcg/marc/

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