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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 1.39 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
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
28=cut 33=cut
29 34
30package Coro; 35package Coro;
31 36
37no warnings qw(uninitialized);
38
32use Coro::State; 39use Coro::State;
33 40
34use base Exporter; 41use base Exporter;
35 42
36$VERSION = 0.05; 43$VERSION = 0.51;
37 44
38@EXPORT = qw(async yield schedule terminate); 45@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}};
40 50
41{ 51{
42 use subs 'async';
43
44 my @async; 52 my @async;
53 my $init;
45 54
46 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 56 sub import {
48 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
51 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
52 my @attrs; 61 my @attrs;
53 for (@_) { 62 for (@_) {
54 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
55 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 }
56 } else { 72 } else {
57 push @attrs, @_; 73 push @attrs, $_;
58 } 74 }
59 } 75 }
60 return $old ? $old->($package, $name, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 77 };
62 } 78 }
63 79
64 sub INIT {
65 async pop @async while @async;
66 }
67} 80}
68 81
69=item $main 82=item $main
70 83
71This coroutine represents the main program. 84This coroutine represents the main program.
72 85
73=cut 86=cut
74 87
75our $main = new Coro; 88our $main = new Coro;
76 89
77=item $current 90=item $current (or as function: current)
78 91
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 92The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 93
81=cut 94=cut
82 95
… …
84if ($current) { 97if ($current) {
85 $main->{specific} = $current->{specific}; 98 $main->{specific} = $current->{specific};
86} 99}
87 100
88our $current = $main; 101our $current = $main;
102
103sub current() { $current }
89 104
90=item $idle 105=item $idle
91 106
92The 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
93implementation prints "FATAL: deadlock detected" and exits. 108implementation prints "FATAL: deadlock detected" and exits.
… …
98our $idle = new Coro sub { 113our $idle = new Coro sub {
99 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
100 exit(51); 115 exit(51);
101}; 116};
102 117
103# we really need priorities... 118# this coroutine is necessary because a coroutine
104## my @ready; #d# 119# cannot destroy itself.
105our @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};
106 133
107# static methods. not really. 134# static methods. not really.
108 135
109=head2 STATIC METHODS 136=head2 STATIC METHODS
110 137
… …
128 155
129=cut 156=cut
130 157
131sub async(&@) { 158sub async(&@) {
132 my $pid = new Coro @_; 159 my $pid = new Coro @_;
160 $manager->ready; # this ensures that the stack is cloned from the manager
133 $pid->ready; 161 $pid->ready;
134 $pid; 162 $pid;
135} 163}
136 164
137=item schedule 165=item schedule
… …
140into the ready queue, so calling this function usually means you will 168into the ready queue, so calling this function usually means you will
141never be called again. 169never be called again.
142 170
143=cut 171=cut
144 172
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 173=item cede
154 174
155Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
156ready 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.
157 178
158=cut 179=cut
159 180
160sub 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 {
161 $current->ready; 190 $current->cancel;
162 &schedule; 191 &schedule;
163} 192 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} 193}
177 194
178=back 195=back
179 196
180# dynamic methods 197# dynamic methods
… …
207 }, $class; 224 }, $class;
208} 225}
209 226
210=item $process->ready 227=item $process->ready
211 228
212Put the current process into the ready queue. 229Put the given process into the ready queue.
213 230
214=cut 231=cut
215 232
216sub ready { 233=item $process->cancel
234
235Like C<terminate>, but terminates the specified process instead.
236
237=cut
238
239sub cancel {
217 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];
218} 283}
219 284
220=back 285=back
221 286
222=cut 287=cut
223 288
2241; 2891;
225 290
226=head1 BUGS 291=head1 BUGS/LIMITATIONS
227 292
228 - 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.
229 support for coroutines (like it does for threads). 294 very bad things might happen otherwise (usually segfaults).
230 - there is still a memleak on coroutine termination that I could not 295 - this module is not thread-safe. You must only ever use this module from
231 identify. Could be as small as a single SV. 296 the same thread (this requirement might be loosened in the future to
232 - this module is not well-tested. 297 allow per-thread schedulers, but Coro::State does not yet allow this).
233 298
234=head1 SEE ALSO 299=head1 SEE ALSO
235 300
236L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 301L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
237L<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>.
238 304
239=head1 AUTHOR 305=head1 AUTHOR
240 306
241 Marc Lehmann <pcg@goof.com> 307 Marc Lehmann <pcg@goof.com>
242 http://www.goof.com/pcg/marc/ 308 http://www.goof.com/pcg/marc/

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