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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 1.39 by root, Tue Oct 9 00:39:08 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$VERSION = 0.51;
42 44
43@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
44@EXPORT_OK = qw($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 $manager;
122$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 (pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy;
130 &schedule;
131 }
132};
110 133
111# static methods. not really. 134# static methods. not really.
112 135
113=head2 STATIC METHODS 136=head2 STATIC METHODS
114 137
… …
132 155
133=cut 156=cut
134 157
135sub async(&@) { 158sub async(&@) {
136 my $pid = new Coro @_; 159 my $pid = new Coro @_;
160 $manager->ready; # this ensures that the stack is cloned from the manager
137 $pid->ready; 161 $pid->ready;
138 $pid; 162 $pid;
139} 163}
140 164
141=item schedule 165=item schedule
… …
144into the ready queue, so calling this function usually means you will 168into the ready queue, so calling this function usually means you will
145never be called again. 169never be called again.
146 170
147=cut 171=cut
148 172
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 173=item cede
158 174
159Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
160ready queue and calls C<schedule>. 176ready queue and calls C<schedule>, which has the effect of giving up the
177current "timeslice" to other coroutines of the same or higher priority.
161 178
162=cut 179=cut
163 180
164sub yield { 181=item terminate
182
183Terminates the current process.
184
185Future versions of this function will allow result arguments.
186
187=cut
188
189sub terminate {
165 $current->ready; 190 $current->cancel;
166 &schedule; 191 &schedule;
167} 192 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} 193}
181 194
182=back 195=back
183 196
184# dynamic methods 197# dynamic methods
… …
211 }, $class; 224 }, $class;
212} 225}
213 226
214=item $process->ready 227=item $process->ready
215 228
216Put the current process into the ready queue. 229Put the given process into the ready queue.
217 230
218=cut 231=cut
219 232
220sub ready { 233=item $process->cancel
234
235Like C<terminate>, but terminates the specified process instead.
236
237=cut
238
239sub cancel {
221 push @ready, $_[0]; 240 push @destroy, $_[0];
241 $manager->ready;
242 &schedule if $current == $_[0];
243}
244
245=item $oldprio = $process->prio($newprio)
246
247Sets the priority of the process. Higher priority processes get run before
248lower priority processes. Priorities are smalled signed integer (currently
249-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
250tag :prio to get then):
251
252 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
253 3 > 1 > 0 > -1 > -3 > -4
254
255 # set priority to HIGH
256 current->prio(PRIO_HIGH);
257
258The idle coroutine ($Coro::idle) always has a lower priority than any
259existing coroutine.
260
261Changing the priority of the current process will take effect immediately,
262but changing the priority of processes in the ready queue (but not
263running) will only take effect after the next schedule (of that
264process). This is a bug that will be fixed in some future version.
265
266=cut
267
268sub prio {
269 my $old = $_[0]{prio};
270 $_[0]{prio} = $_[1] if @_ > 1;
271 $old;
272}
273
274=item $newprio = $process->nice($change)
275
276Similar to C<prio>, but subtract the given value from the priority (i.e.
277higher values mean lower priority, just as in unix).
278
279=cut
280
281sub nice {
282 $_[0]{prio} -= $_[1];
222} 283}
223 284
224=back 285=back
225 286
226=cut 287=cut
227 288
2281; 2891;
229 290
230=head1 BUGS/LIMITATIONS 291=head1 BUGS/LIMITATIONS
231 292
232 - could be faster, especially when the core would introduce special 293 - you must make very sure that no coro is still active on global destruction.
233 support for coroutines (like it does for threads). 294 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 295 - 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 296 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). 297 allow per-thread schedulers, but Coro::State does not yet allow this).
243 298
244=head1 SEE ALSO 299=head1 SEE ALSO
245 300
246L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 301L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
247L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 302L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
303L<Coro::Handle>, L<Coro::Socket>.
248 304
249=head1 AUTHOR 305=head1 AUTHOR
250 306
251 Marc Lehmann <pcg@goof.com> 307 Marc Lehmann <pcg@goof.com>
252 http://www.goof.com/pcg/marc/ 308 http://www.goof.com/pcg/marc/

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