ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/Coro/Coro.pm
(Generate patch)

Comparing Coro/Coro.pm (file contents):
Revision 1.13 by root, Tue Jul 17 00:24:14 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
24Threads but don't run in parallel.
25
26This module is still experimental, see the BUGS section below.
27
28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
37no warnings qw(uninitialized);
38
27use Coro::State; 39use Coro::State;
28 40
29use base Exporter; 41use base Exporter;
30 42
31$VERSION = 0.05; 43$VERSION = 0.51;
32 44
33@EXPORT = qw(async yield schedule terminate); 45@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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}};
35 50
36{ 51{
37 use subs 'async';
38
39 my @async; 52 my @async;
53 my $init;
40 54
41 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 56 sub import {
43 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
47 my @attrs; 61 my @attrs;
48 for (@_) { 62 for (@_) {
49 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
50 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 }
51 } else { 72 } else {
52 push @attrs, @_; 73 push @attrs, $_;
53 } 74 }
54 } 75 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 77 };
57 } 78 }
58 79
59 sub INIT {
60 async pop @async while @async;
61 }
62} 80}
63 81
64=item $main 82=item $main
65 83
66This coroutine represents the main program. 84This coroutine represents the main program.
67 85
68=cut 86=cut
69 87
70our $main = new Coro; 88our $main = new Coro;
71 89
72=item $current 90=item $current (or as function: current)
73 91
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 92The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 93
76=cut 94=cut
77 95
… …
79if ($current) { 97if ($current) {
80 $main->{specific} = $current->{specific}; 98 $main->{specific} = $current->{specific};
81} 99}
82 100
83our $current = $main; 101our $current = $main;
102
103sub current() { $current }
84 104
85=item $idle 105=item $idle
86 106
87The coroutine to switch to when no other coroutine is running. The default 107The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 108implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 113our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 115 exit(51);
96}; 116};
97 117
98# we really need priorities... 118# this coroutine is necessary because a coroutine
99## my @ready; #d# 119# cannot destroy itself.
100our @ready = (); # the ready queue. hehe, rather broken ;) 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};
101 133
102# static methods. not really. 134# static methods. not really.
103 135
104=head2 STATIC METHODS 136=head2 STATIC METHODS
105 137
… …
123 155
124=cut 156=cut
125 157
126sub async(&@) { 158sub async(&@) {
127 my $pid = new Coro @_; 159 my $pid = new Coro @_;
160 $manager->ready; # this ensures that the stack is cloned from the manager
128 $pid->ready; 161 $pid->ready;
129 $pid; 162 $pid;
130} 163}
131 164
132=item schedule 165=item schedule
… …
135into the ready queue, so calling this function usually means you will 168into the ready queue, so calling this function usually means you will
136never be called again. 169never be called again.
137 170
138=cut 171=cut
139 172
140my $prev;
141
142sub schedule {
143 # should be done using priorities :(
144 ($prev, $current) = ($current, shift @ready || $idle);
145 Coro::State::transfer($prev, $current);
146}
147
148=item yield 173=item cede
149 174
150Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
151ready 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.
152 178
153=cut 179=cut
154 180
155sub 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 {
156 $current->ready; 190 $current->cancel;
157 &schedule; 191 &schedule;
158} 192 die; # NORETURN
159
160=item terminate
161
162Terminates the current process.
163
164Future versions of this function will allow result arguments.
165
166=cut
167
168sub terminate {
169 $current->{_results} = [@_];
170 &schedule;
171} 193}
172 194
173=back 195=back
174 196
175# dynamic methods 197# dynamic methods
… …
202 }, $class; 224 }, $class;
203} 225}
204 226
205=item $process->ready 227=item $process->ready
206 228
207Put the current process into the ready queue. 229Put the given process into the ready queue.
208 230
209=cut 231=cut
210 232
211sub ready { 233=item $process->cancel
234
235Like C<terminate>, but terminates the specified process instead.
236
237=cut
238
239sub cancel {
212 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];
213} 283}
214 284
215=back 285=back
216 286
217=cut 287=cut
218 288
2191; 2891;
220 290
291=head1 BUGS/LIMITATIONS
292
293 - you must make very sure that no coro is still active on global destruction.
294 very bad things might happen otherwise (usually segfaults).
295 - this module is not thread-safe. You must only ever use this module from
296 the same thread (this requirement might be loosened in the future to
297 allow per-thread schedulers, but Coro::State does not yet allow this).
298
221=head1 SEE ALSO 299=head1 SEE ALSO
222 300
223L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 301L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
224L<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>.
225 304
226=head1 AUTHOR 305=head1 AUTHOR
227 306
228 Marc Lehmann <pcg@goof.com> 307 Marc Lehmann <pcg@goof.com>
229 http://www.goof.com/pcg/marc/ 308 http://www.goof.com/pcg/marc/

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines