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Comparing Coro/Coro.pm (file contents):
Revision 1.14 by root, Tue Jul 17 02:21:56 2001 UTC vs.
Revision 1.35 by root, Mon Sep 24 00:16:30 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
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
28=cut 33=cut
29 34
30package Coro; 35package Coro;
31 36
32use Coro::State; 37use Coro::State;
33 38
34use base Exporter; 39use base Exporter;
35 40
36$VERSION = 0.05; 41$VERSION = 0.5;
37 42
38@EXPORT = qw(async yield schedule terminate); 43@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($current); 44%EXPORT_TAGS = (
45 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
46);
47@EXPORT_OK = @{$EXPORT_TAGS{prio}};
40 48
41{ 49{
42 use subs 'async';
43
44 my @async; 50 my @async;
51 my $init;
45 52
46 # this way of handling attributes simply is NOT scalable ;() 53 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 54 sub import {
48 Coro->export_to_level(1, @_); 55 Coro->export_to_level(1, @_);
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 56 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
51 my ($package, $ref) = (shift, shift); 58 my ($package, $ref) = (shift, shift);
52 my @attrs; 59 my @attrs;
53 for (@_) { 60 for (@_) {
54 if ($_ eq "Coro") { 61 if ($_ eq "Coro") {
55 push @async, $ref; 62 push @async, $ref;
63 unless ($init++) {
64 eval q{
65 sub INIT {
66 &async(pop @async) while @async;
67 }
68 };
69 }
56 } else { 70 } else {
57 push @attrs, @_; 71 push @attrs, $_;
58 } 72 }
59 } 73 }
60 return $old ? $old->($package, $name, @attrs) : @attrs; 74 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 75 };
62 } 76 }
63 77
64 sub INIT {
65 async pop @async while @async;
66 }
67} 78}
68 79
69=item $main 80=item $main
70 81
71This coroutine represents the main program. 82This coroutine represents the main program.
72 83
73=cut 84=cut
74 85
75our $main = new Coro; 86our $main = new Coro;
76 87
77=item $current 88=item $current (or as function: current)
78 89
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 90The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 91
81=cut 92=cut
82 93
… …
84if ($current) { 95if ($current) {
85 $main->{specific} = $current->{specific}; 96 $main->{specific} = $current->{specific};
86} 97}
87 98
88our $current = $main; 99our $current = $main;
100
101sub current() { $current }
89 102
90=item $idle 103=item $idle
91 104
92The coroutine to switch to when no other coroutine is running. The default 105The coroutine to switch to when no other coroutine is running. The default
93implementation prints "FATAL: deadlock detected" and exits. 106implementation prints "FATAL: deadlock detected" and exits.
… …
98our $idle = new Coro sub { 111our $idle = new Coro sub {
99 print STDERR "FATAL: deadlock detected\n"; 112 print STDERR "FATAL: deadlock detected\n";
100 exit(51); 113 exit(51);
101}; 114};
102 115
103# we really need priorities... 116# this coroutine is necessary because a coroutine
104## my @ready; #d# 117# cannot destroy itself.
105our @ready = (); # the ready queue. hehe, rather broken ;) 118my @destroy;
119my $manager = new Coro sub {
120 while() {
121 delete ((pop @destroy)->{_coro_state}) while @destroy;
122 &schedule;
123 }
124};
106 125
107# static methods. not really. 126# static methods. not really.
108 127
109=head2 STATIC METHODS 128=head2 STATIC METHODS
110 129
… …
128 147
129=cut 148=cut
130 149
131sub async(&@) { 150sub async(&@) {
132 my $pid = new Coro @_; 151 my $pid = new Coro @_;
152 $manager->ready; # this ensures that the stack is cloned from the manager
133 $pid->ready; 153 $pid->ready;
134 $pid; 154 $pid;
135} 155}
136 156
137=item schedule 157=item schedule
… …
140into the ready queue, so calling this function usually means you will 160into the ready queue, so calling this function usually means you will
141never be called again. 161never be called again.
142 162
143=cut 163=cut
144 164
145my $prev;
146
147sub schedule {
148 # should be done using priorities :(
149 ($prev, $current) = ($current, shift @ready || $idle);
150 Coro::State::transfer($prev, $current);
151}
152
153=item yield 165=item cede
154 166
155Yield to other processes. This function puts the current process into the 167"Cede" to other processes. This function puts the current process into the
156ready queue and calls C<schedule>. 168ready queue and calls C<schedule>, which has the effect of giving up the
169current "timeslice" to other coroutines of the same or higher priority.
157 170
158=cut 171=cut
159 172
160sub yield { 173=item terminate
174
175Terminates the current process.
176
177Future versions of this function will allow result arguments.
178
179=cut
180
181sub terminate {
161 $current->ready; 182 $current->cancel;
162 &schedule; 183 &schedule;
163} 184 die; # NORETURN
164
165=item terminate
166
167Terminates the current process.
168
169Future versions of this function will allow result arguments.
170
171=cut
172
173sub terminate {
174 $current->{_results} = [@_];
175 &schedule;
176} 185}
177 186
178=back 187=back
179 188
180# dynamic methods 189# dynamic methods
… …
211 220
212Put the current process into the ready queue. 221Put the current process into the ready queue.
213 222
214=cut 223=cut
215 224
216sub ready { 225=item $process->cancel
226
227Like C<terminate>, but terminates the specified process instead.
228
229=cut
230
231sub cancel {
217 push @ready, $_[0]; 232 push @destroy, $_[0];
233 $manager->ready;
234 &schedule if $current == $_[0];
235}
236
237=item $oldprio = $process->prio($newprio)
238
239Sets the priority of the process. Higher priority processes get run before
240lower priority processes. Priorities are smalled signed integer (currently
241-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
242tag :prio to get then):
243
244 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
245 3 > 1 > 0 > -1 > -3 > -4
246
247 # set priority to HIGH
248 current->prio(PRIO_HIGH);
249
250The idle coroutine ($Coro::idle) always has a lower priority than any
251existing coroutine.
252
253Changing the priority of the current process will take effect immediately,
254but changing the priority of processes in the ready queue (but not
255running) will only take effect after the next schedule (of that
256process). This is a bug that will be fixed in some future version.
257
258=cut
259
260sub prio {
261 my $old = $_[0]{prio};
262 $_[0]{prio} = $_[1] if @_ > 1;
263 $old;
264}
265
266=item $newprio = $process->nice($change)
267
268Similar to C<prio>, but subtract the given value from the priority (i.e.
269higher values mean lower priority, just as in unix).
270
271=cut
272
273sub nice {
274 $_[0]{prio} -= $_[1];
218} 275}
219 276
220=back 277=back
221 278
222=cut 279=cut
223 280
2241; 2811;
225 282
226=head1 BUGS 283=head1 BUGS/LIMITATIONS
227 284
228 - could be faster, especially when the core would introduce special 285 - you must make very sure that no coro is still active on global destruction.
229 support for coroutines (like it does for threads). 286 very bad things might happen otherwise (usually segfaults).
230 - there is still a memleak on coroutine termination that I could not 287 - this module is not thread-safe. You must only ever use this module from
231 identify. Could be as small as a single SV. 288 the same thread (this requirement might be loosened in the future to
232 - this module is not well-tested. 289 allow per-thread schedulers, but Coro::State does not yet allow this).
233 290
234=head1 SEE ALSO 291=head1 SEE ALSO
235 292
236L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 293L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
237L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 294L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
295L<Coro::Handle>, L<Coro::Socket>.
238 296
239=head1 AUTHOR 297=head1 AUTHOR
240 298
241 Marc Lehmann <pcg@goof.com> 299 Marc Lehmann <pcg@goof.com>
242 http://www.goof.com/pcg/marc/ 300 http://www.goof.com/pcg/marc/

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