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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 1.52 by root, Tue May 27 00:26:34 2003 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 = 0.05; 41$VERSION = 0.652;
37 42
38@EXPORT = qw(async yield schedule terminate); 43@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}
79
80=over 4
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 while (@destroy) {
130 my $coro = pop @destroy;
131 $coro->{status} ||= [];
132 $_->ready for @{delete $coro->{join} || []};
133 $coro->{_coro_state} = $manager->{_coro_state};
134 }
135 &schedule;
136 }
137};
106 138
107# static methods. not really. 139# static methods. not really.
140
141=back
108 142
109=head2 STATIC METHODS 143=head2 STATIC METHODS
110 144
111Static methods are actually functions that operate on the current process only. 145Static methods are actually functions that operate on the current process only.
112 146
… …
128 162
129=cut 163=cut
130 164
131sub async(&@) { 165sub async(&@) {
132 my $pid = new Coro @_; 166 my $pid = new Coro @_;
167 $manager->ready; # this ensures that the stack is cloned from the manager
133 $pid->ready; 168 $pid->ready;
134 $pid; 169 $pid;
135} 170}
136 171
137=item schedule 172=item schedule
… …
140into the ready queue, so calling this function usually means you will 175into the ready queue, so calling this function usually means you will
141never be called again. 176never be called again.
142 177
143=cut 178=cut
144 179
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 180=item cede
154 181
155Yield to other processes. This function puts the current process into the 182"Cede" to other processes. This function puts the current process into the
156ready queue and calls C<schedule>. 183ready queue and calls C<schedule>, which has the effect of giving up the
184current "timeslice" to other coroutines of the same or higher priority.
157 185
158=cut 186=cut
159 187
160sub yield { 188=item terminate [arg...]
189
190Terminates the current process.
191
192Future versions of this function will allow result arguments.
193
194=cut
195
196sub terminate {
197 $current->{status} = [@_];
161 $current->ready; 198 $current->cancel;
162 &schedule; 199 &schedule;
163} 200 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} 201}
177 202
178=back 203=back
179 204
180# dynamic methods 205# dynamic methods
… …
186=over 4 211=over 4
187 212
188=item new Coro \&sub [, @args...] 213=item new Coro \&sub [, @args...]
189 214
190Create a new process and return it. When the sub returns the process 215Create a new process and return it. When the sub returns the process
191automatically terminates. To start the process you must first put it into 216automatically terminates as if C<terminate> with the returned values were
217called. To make the process run you must first put it into the ready queue
192the ready queue by calling the ready method. 218by calling the ready method.
193
194The coderef you submit MUST NOT be a closure that refers to variables
195in an outer scope. This does NOT work. Pass arguments into it instead.
196 219
197=cut 220=cut
198 221
199sub _newcoro { 222sub _newcoro {
200 terminate &{+shift}; 223 terminate &{+shift};
… …
207 }, $class; 230 }, $class;
208} 231}
209 232
210=item $process->ready 233=item $process->ready
211 234
212Put the current process into the ready queue. 235Put the given process into the ready queue.
213 236
214=cut 237=cut
215 238
216sub ready { 239=item $process->cancel
240
241Like C<terminate>, but terminates the specified process instead.
242
243=cut
244
245sub cancel {
217 push @ready, $_[0]; 246 push @destroy, $_[0];
247 $manager->ready;
248 &schedule if $current == $_[0];
249}
250
251=item $process->join
252
253Wait until the coroutine terminates and return any values given to the
254C<terminate> function. C<join> can be called multiple times from multiple
255processes.
256
257=cut
258
259sub join {
260 my $self = shift;
261 unless ($self->{status}) {
262 push @{$self->{join}}, $current;
263 &schedule;
264 }
265 wantarray ? @{$self->{status}} : $self->{status}[0];
266}
267
268=item $oldprio = $process->prio($newprio)
269
270Sets (or gets, if the argument is missing) the priority of the
271process. Higher priority processes get run before lower priority
272processes. Priorities are small signed integers (currently -4 .. +3),
273that you can refer to using PRIO_xxx constants (use the import tag :prio
274to get then):
275
276 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
277 3 > 1 > 0 > -1 > -3 > -4
278
279 # set priority to HIGH
280 current->prio(PRIO_HIGH);
281
282The idle coroutine ($Coro::idle) always has a lower priority than any
283existing coroutine.
284
285Changing the priority of the current process will take effect immediately,
286but changing the priority of processes in the ready queue (but not
287running) will only take effect after the next schedule (of that
288process). This is a bug that will be fixed in some future version.
289
290=cut
291
292sub prio {
293 my $old = $_[0]{prio};
294 $_[0]{prio} = $_[1] if @_ > 1;
295 $old;
296}
297
298=item $newprio = $process->nice($change)
299
300Similar to C<prio>, but subtract the given value from the priority (i.e.
301higher values mean lower priority, just as in unix).
302
303=cut
304
305sub nice {
306 $_[0]{prio} -= $_[1];
307}
308
309=item $olddesc = $process->desc($newdesc)
310
311Sets (or gets in case the argument is missing) the description for this
312process. This is just a free-form string you can associate with a process.
313
314=cut
315
316sub desc {
317 my $old = $_[0]{desc};
318 $_[0]{desc} = $_[1] if @_ > 1;
319 $old;
218} 320}
219 321
220=back 322=back
221 323
222=cut 324=cut
223 325
2241; 3261;
225 327
226=head1 BUGS 328=head1 BUGS/LIMITATIONS
227 329
228 - could be faster, especially when the core would introduce special 330 - you must make very sure that no coro is still active on global
229 support for coroutines (like it does for threads). 331 destruction. very bad things might happen otherwise (usually segfaults
230 - there is still a memleak on coroutine termination that I could not 332 or "panic: top_env").
231 identify. Could be as small as a single SV. 333
232 - this module is not well-tested. 334 - this module is not thread-safe. You should only ever use this module
335 from the same thread (this requirement might be losened in the future
336 to allow per-thread schedulers, but Coro::State does not yet allow
337 this).
233 338
234=head1 SEE ALSO 339=head1 SEE ALSO
235 340
236L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 341L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
237L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 342L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
343L<Coro::Handle>, L<Coro::Socket>.
238 344
239=head1 AUTHOR 345=head1 AUTHOR
240 346
241 Marc Lehmann <pcg@goof.com> 347 Marc Lehmann <pcg@goof.com>
242 http://www.goof.com/pcg/marc/ 348 http://www.goof.com/pcg/marc/

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