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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 1.42 by root, Tue Nov 6 20:37:20 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. 26In this module, coroutines are defined as "callchain + lexical variables
27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
27 30
28=cut 31=cut
29 32
30package Coro; 33package Coro;
31 34
35no warnings qw(uninitialized);
36
32use Coro::State; 37use Coro::State;
33 38
34use base Exporter; 39use base Exporter;
35 40
36$VERSION = 0.07; 41$VERSION = 0.52;
37 42
38@EXPORT = qw(async yield schedule terminate); 43@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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
104my @ready; # the ready queue. hehe, rather broken ;) 117# cannot destroy itself.
118my @destroy;
119my $manager;
120$manager = new Coro sub {
121 while() {
122 # by overwriting the state object with the manager we destroy it
123 # while still being able to schedule this coroutine (in case it has
124 # been readied multiple times. this is harmless since the manager
125 # can be called as many times as neccessary and will always
126 # remove itself from the runqueue
127 while (@destroy) {
128 my $coro = pop @destroy;
129 $coro->{status} ||= [];
130 $_->ready for @{delete $coro->{join} || []};
131 $coro->{_coro_state} = $manager->{_coro_state};
132 }
133 &schedule;
134 }
135};
105 136
106# static methods. not really. 137# static methods. not really.
107 138
108=head2 STATIC METHODS 139=head2 STATIC METHODS
109 140
… …
127 158
128=cut 159=cut
129 160
130sub async(&@) { 161sub async(&@) {
131 my $pid = new Coro @_; 162 my $pid = new Coro @_;
163 $manager->ready; # this ensures that the stack is cloned from the manager
132 $pid->ready; 164 $pid->ready;
133 $pid; 165 $pid;
134} 166}
135 167
136=item schedule 168=item schedule
… …
139into the ready queue, so calling this function usually means you will 171into the ready queue, so calling this function usually means you will
140never be called again. 172never be called again.
141 173
142=cut 174=cut
143 175
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 176=item cede
153 177
154Yield to other processes. This function puts the current process into the 178"Cede" to other processes. This function puts the current process into the
155ready queue and calls C<schedule>. 179ready queue and calls C<schedule>, which has the effect of giving up the
180current "timeslice" to other coroutines of the same or higher priority.
156 181
157=cut 182=cut
158 183
159sub yield { 184=item terminate [arg...]
185
186Terminates the current process.
187
188Future versions of this function will allow result arguments.
189
190=cut
191
192sub terminate {
193 $current->{status} = [@_];
160 $current->ready; 194 $current->cancel;
161 &schedule; 195 &schedule;
162} 196 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} 197}
176 198
177=back 199=back
178 200
179# dynamic methods 201# dynamic methods
… …
185=over 4 207=over 4
186 208
187=item new Coro \&sub [, @args...] 209=item new Coro \&sub [, @args...]
188 210
189Create a new process and return it. When the sub returns the process 211Create a new process and return it. When the sub returns the process
190automatically terminates. To start the process you must first put it into 212automatically terminates as if C<terminate> with the returned values were
213called. To make the process run you must first put it into the ready queue
191the ready queue by calling the ready method. 214by calling the ready method.
192
193The coderef you submit MUST NOT be a closure that refers to variables
194in an outer scope. This does NOT work. Pass arguments into it instead.
195 215
196=cut 216=cut
197 217
198sub _newcoro { 218sub _newcoro {
199 terminate &{+shift}; 219 terminate &{+shift};
… …
206 }, $class; 226 }, $class;
207} 227}
208 228
209=item $process->ready 229=item $process->ready
210 230
211Put the current process into the ready queue. 231Put the given process into the ready queue.
212 232
213=cut 233=cut
214 234
215sub ready { 235=item $process->cancel
236
237Like C<terminate>, but terminates the specified process instead.
238
239=cut
240
241sub cancel {
216 push @ready, $_[0]; 242 push @destroy, $_[0];
243 $manager->ready;
244 &schedule if $current == $_[0];
245}
246
247=item $process->join
248
249Wait until the coroutine terminates and return any values given to the
250C<terminate> function. C<join> can be called multiple times from multiple
251processes.
252
253=cut
254
255sub join {
256 my $self = shift;
257 unless ($self->{status}) {
258 push @{$self->{join}}, $current;
259 &schedule;
260 }
261 wantarray ? @{$self->{status}} : $self->{status}[0];
262}
263
264=item $oldprio = $process->prio($newprio)
265
266Sets (or gets, if the argument is missing) the priority of the
267process. Higher priority processes get run before lower priority
268processes. Priorities are smalled signed integer (currently -4 .. +3),
269that you can refer to using PRIO_xxx constants (use the import tag :prio
270to get then):
271
272 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
273 3 > 1 > 0 > -1 > -3 > -4
274
275 # set priority to HIGH
276 current->prio(PRIO_HIGH);
277
278The idle coroutine ($Coro::idle) always has a lower priority than any
279existing coroutine.
280
281Changing the priority of the current process will take effect immediately,
282but changing the priority of processes in the ready queue (but not
283running) will only take effect after the next schedule (of that
284process). This is a bug that will be fixed in some future version.
285
286=cut
287
288sub prio {
289 my $old = $_[0]{prio};
290 $_[0]{prio} = $_[1] if @_ > 1;
291 $old;
292}
293
294=item $newprio = $process->nice($change)
295
296Similar to C<prio>, but subtract the given value from the priority (i.e.
297higher values mean lower priority, just as in unix).
298
299=cut
300
301sub nice {
302 $_[0]{prio} -= $_[1];
303}
304
305=item $olddesc = $process->desc($newdesc)
306
307Sets (or gets in case the argument is missing) the description for this
308process. This is just a free-form string you can associate with a process.
309
310=cut
311
312sub desc {
313 my $old = $_[0]{desc};
314 $_[0]{desc} = $_[1] if @_ > 1;
315 $old;
217} 316}
218 317
219=back 318=back
220 319
221=cut 320=cut
222 321
2231; 3221;
224 323
225=head1 BUGS 324=head1 BUGS/LIMITATIONS
226 325
227 - could be faster, especially when the core would introduce special 326 - you must make very sure that no coro is still active on global destruction.
228 support for coroutines (like it does for threads). 327 very bad things might happen otherwise (usually segfaults).
229 - there is still a memleak on coroutine termination that I could not 328 - this module is not thread-safe. You should only ever use this module from
230 identify. Could be as small as a single SV. 329 the same thread (this requirement might be loosened in the future to
231 - this module is not well-tested. 330 allow per-thread schedulers, but Coro::State does not yet allow this).
232 331
233=head1 SEE ALSO 332=head1 SEE ALSO
234 333
235L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 334L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
236L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 335L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
336L<Coro::Handle>, L<Coro::Socket>.
237 337
238=head1 AUTHOR 338=head1 AUTHOR
239 339
240 Marc Lehmann <pcg@goof.com> 340 Marc Lehmann <pcg@goof.com>
241 http://www.goof.com/pcg/marc/ 341 http://www.goof.com/pcg/marc/

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