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Comparing Coro/Coro.pm (file contents):
Revision 1.13 by root, Tue Jul 17 00:24:14 2001 UTC vs.
Revision 1.41 by root, Tue Nov 6 20:34:09 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
24Threads but don't run in parallel.
25
26This module is still experimental, see the BUGS section below.
27
28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
37no warnings qw(uninitialized);
38
27use Coro::State; 39use Coro::State;
28 40
29use base Exporter; 41use base Exporter;
30 42
31$VERSION = 0.05; 43$VERSION = 0.52;
32 44
33@EXPORT = qw(async yield schedule terminate); 45@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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}};
35 50
36{ 51{
37 use subs 'async';
38
39 my @async; 52 my @async;
53 my $init;
40 54
41 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 56 sub import {
43 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
47 my @attrs; 61 my @attrs;
48 for (@_) { 62 for (@_) {
49 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
50 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 }
51 } else { 72 } else {
52 push @attrs, @_; 73 push @attrs, $_;
53 } 74 }
54 } 75 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 77 };
57 } 78 }
58 79
59 sub INIT {
60 async pop @async while @async;
61 }
62} 80}
63 81
64=item $main 82=item $main
65 83
66This coroutine represents the main program. 84This coroutine represents the main program.
67 85
68=cut 86=cut
69 87
70our $main = new Coro; 88our $main = new Coro;
71 89
72=item $current 90=item $current (or as function: current)
73 91
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 92The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 93
76=cut 94=cut
77 95
… …
79if ($current) { 97if ($current) {
80 $main->{specific} = $current->{specific}; 98 $main->{specific} = $current->{specific};
81} 99}
82 100
83our $current = $main; 101our $current = $main;
102
103sub current() { $current }
84 104
85=item $idle 105=item $idle
86 106
87The 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
88implementation prints "FATAL: deadlock detected" and exits. 108implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 113our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 115 exit(51);
96}; 116};
97 117
98# we really need priorities... 118# this coroutine is necessary because a coroutine
99## my @ready; #d# 119# cannot destroy itself.
100our @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};
101 138
102# static methods. not really. 139# static methods. not really.
103 140
104=head2 STATIC METHODS 141=head2 STATIC METHODS
105 142
… …
123 160
124=cut 161=cut
125 162
126sub async(&@) { 163sub async(&@) {
127 my $pid = new Coro @_; 164 my $pid = new Coro @_;
165 $manager->ready; # this ensures that the stack is cloned from the manager
128 $pid->ready; 166 $pid->ready;
129 $pid; 167 $pid;
130} 168}
131 169
132=item schedule 170=item schedule
… …
135into the ready queue, so calling this function usually means you will 173into the ready queue, so calling this function usually means you will
136never be called again. 174never be called again.
137 175
138=cut 176=cut
139 177
140my $prev;
141
142sub schedule {
143 # should be done using priorities :(
144 ($prev, $current) = ($current, shift @ready || $idle);
145 Coro::State::transfer($prev, $current);
146}
147
148=item yield 178=item cede
149 179
150Yield to other processes. This function puts the current process into the 180"Cede" to other processes. This function puts the current process into the
151ready queue and calls C<schedule>. 181ready queue and calls C<schedule>, which has the effect of giving up the
182current "timeslice" to other coroutines of the same or higher priority.
152 183
153=cut 184=cut
154 185
155sub yield { 186=item terminate [arg...]
187
188Terminates the current process.
189
190Future versions of this function will allow result arguments.
191
192=cut
193
194sub terminate {
195 $current->{status} = [@_];
156 $current->ready; 196 $current->cancel;
157 &schedule; 197 &schedule;
158} 198 die; # NORETURN
159
160=item terminate
161
162Terminates the current process.
163
164Future versions of this function will allow result arguments.
165
166=cut
167
168sub terminate {
169 $current->{_results} = [@_];
170 &schedule;
171} 199}
172 200
173=back 201=back
174 202
175# dynamic methods 203# dynamic methods
… …
181=over 4 209=over 4
182 210
183=item new Coro \&sub [, @args...] 211=item new Coro \&sub [, @args...]
184 212
185Create a new process and return it. When the sub returns the process 213Create a new process and return it. When the sub returns the process
186automatically terminates. To start the process you must first put it into 214automatically terminates as if C<terminate> with the returned values were
215called. To make the process run you must first put it into the ready queue
187the ready queue by calling the ready method. 216by calling the ready method.
188
189The coderef you submit MUST NOT be a closure that refers to variables
190in an outer scope. This does NOT work. Pass arguments into it instead.
191 217
192=cut 218=cut
193 219
194sub _newcoro { 220sub _newcoro {
195 terminate &{+shift}; 221 terminate &{+shift};
… …
202 }, $class; 228 }, $class;
203} 229}
204 230
205=item $process->ready 231=item $process->ready
206 232
207Put the current process into the ready queue. 233Put the given process into the ready queue.
208 234
209=cut 235=cut
210 236
211sub ready { 237=item $process->cancel
238
239Like C<terminate>, but terminates the specified process instead.
240
241=cut
242
243sub cancel {
212 push @ready, $_[0]; 244 push @destroy, $_[0];
245 $manager->ready;
246 &schedule if $current == $_[0];
247}
248
249=item $process->join
250
251Wait until the coroutine terminates and return any values given to the
252C<terminate> function. C<join> can be called multiple times from multiple
253processes.
254
255=cut
256
257sub join {
258 my $self = shift;
259 unless ($self->{status}) {
260 push @{$self->{join}}, $current;
261 &schedule;
262 }
263 wantarray ? @{$self->{status}} : $self->{status}[0];
264}
265
266=item $oldprio = $process->prio($newprio)
267
268Sets (or gets, if the argument is missing) the priority of the
269process. Higher priority processes get run before lower priority
270processes. Priorities are smalled signed integer (currently -4 .. +3),
271that you can refer to using PRIO_xxx constants (use the import tag :prio
272to get then):
273
274 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
275 3 > 1 > 0 > -1 > -3 > -4
276
277 # set priority to HIGH
278 current->prio(PRIO_HIGH);
279
280The idle coroutine ($Coro::idle) always has a lower priority than any
281existing coroutine.
282
283Changing the priority of the current process will take effect immediately,
284but changing the priority of processes in the ready queue (but not
285running) will only take effect after the next schedule (of that
286process). This is a bug that will be fixed in some future version.
287
288=cut
289
290sub prio {
291 my $old = $_[0]{prio};
292 $_[0]{prio} = $_[1] if @_ > 1;
293 $old;
294}
295
296=item $newprio = $process->nice($change)
297
298Similar to C<prio>, but subtract the given value from the priority (i.e.
299higher values mean lower priority, just as in unix).
300
301=cut
302
303sub nice {
304 $_[0]{prio} -= $_[1];
305}
306
307=item $olddesc = $process->desc($newdesc)
308
309Sets (or gets in case the argument is missing) the description for this
310process. This is just a free-form string you can associate with a process.
311
312=cut
313
314sub desc {
315 my $old = $_[0]{desc};
316 $_[0]{desc} = $_[1] if @_ > 1;
317 $old;
213} 318}
214 319
215=back 320=back
216 321
217=cut 322=cut
218 323
2191; 3241;
220 325
326=head1 BUGS/LIMITATIONS
327
328 - you must make very sure that no coro is still active on global destruction.
329 very bad things might happen otherwise (usually segfaults).
330 - this module is not thread-safe. You must only ever use this module from
331 the same thread (this requirement might be loosened in the future to
332 allow per-thread schedulers, but Coro::State does not yet allow this).
333
221=head1 SEE ALSO 334=head1 SEE ALSO
222 335
223L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 336L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
224L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 337L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
338L<Coro::Handle>, L<Coro::Socket>.
225 339
226=head1 AUTHOR 340=head1 AUTHOR
227 341
228 Marc Lehmann <pcg@goof.com> 342 Marc Lehmann <pcg@goof.com>
229 http://www.goof.com/pcg/marc/ 343 http://www.goof.com/pcg/marc/

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