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Comparing Coro/Coro.pm (file contents):
Revision 1.16 by root, Tue Jul 17 15:42:28 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
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 = 0.07; 43$VERSION = 0.5;
37 44
38@EXPORT = qw(async yield schedule terminate); 45@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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
104my @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};
105 132
106# static methods. not really. 133# static methods. not really.
107 134
108=head2 STATIC METHODS 135=head2 STATIC METHODS
109 136
… …
127 154
128=cut 155=cut
129 156
130sub async(&@) { 157sub async(&@) {
131 my $pid = new Coro @_; 158 my $pid = new Coro @_;
159 $manager->ready; # this ensures that the stack is cloned from the manager
132 $pid->ready; 160 $pid->ready;
133 $pid; 161 $pid;
134} 162}
135 163
136=item schedule 164=item schedule
… …
139into the ready queue, so calling this function usually means you will 167into the ready queue, so calling this function usually means you will
140never be called again. 168never be called again.
141 169
142=cut 170=cut
143 171
144my $prev;
145
146sub schedule {
147 # should be done using priorities :(
148 ($prev, $current) = ($current, shift @ready || $idle);
149 Coro::State::transfer($prev, $current);
150}
151
152=item yield 172=item cede
153 173
154Yield to other processes. This function puts the current process into the 174"Cede" to other processes. This function puts the current process into the
155ready 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.
156 177
157=cut 178=cut
158 179
159sub 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 {
160 $current->ready; 189 $current->cancel;
161 &schedule; 190 &schedule;
162} 191 die; # NORETURN
163
164=item terminate
165
166Terminates the current process.
167
168Future versions of this function will allow result arguments.
169
170=cut
171
172sub terminate {
173 $current->{_results} = [@_];
174 &schedule;
175} 192}
176 193
177=back 194=back
178 195
179# dynamic methods 196# dynamic methods
… …
210 227
211Put the current process into the ready queue. 228Put the current process into the ready queue.
212 229
213=cut 230=cut
214 231
215sub ready { 232=item $process->cancel
233
234Like C<terminate>, but terminates the specified process instead.
235
236=cut
237
238sub cancel {
216 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];
217} 282}
218 283
219=back 284=back
220 285
221=cut 286=cut
222 287
2231; 2881;
224 289
225=head1 BUGS 290=head1 BUGS/LIMITATIONS
226 291
227 - 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.
228 support for coroutines (like it does for threads). 293 very bad things might happen otherwise (usually segfaults).
229 - there is still a memleak on coroutine termination that I could not 294 - this module is not thread-safe. You must only ever use this module from
230 identify. Could be as small as a single SV. 295 the same thread (this requirement might be loosened in the future to
231 - this module is not well-tested. 296 allow per-thread schedulers, but Coro::State does not yet allow this).
232 297
233=head1 SEE ALSO 298=head1 SEE ALSO
234 299
235L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 300L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
236L<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>.
237 303
238=head1 AUTHOR 304=head1 AUTHOR
239 305
240 Marc Lehmann <pcg@goof.com> 306 Marc Lehmann <pcg@goof.com>
241 http://www.goof.com/pcg/marc/ 307 http://www.goof.com/pcg/marc/

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