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Comparing Coro/Coro.pm (file contents):
Revision 1.20 by root, Sat Jul 21 18:21:45 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 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 28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W), that is, a coroutine has it's own callchain, it's 29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 30callchain, it's own set of lexicals and it's own set of perl's most
31variables. 31important global variables.
32 32
33=cut 33=cut
34 34
35package Coro; 35package Coro;
36 36
37no warnings qw(uninitialized);
38
37use Coro::State; 39use Coro::State;
38 40
39use base Exporter; 41use base Exporter;
40 42
41$VERSION = 0.10; 43$VERSION = 0.52;
42 44
43@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
44@EXPORT_OK = qw($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}};
45 50
46{ 51{
47 my @async; 52 my @async;
53 my $init;
48 54
49 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
50 sub import { 56 sub import {
51 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
52 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
54 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
55 my @attrs; 61 my @attrs;
56 for (@_) { 62 for (@_) {
57 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
58 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 }
59 } else { 72 } else {
60 push @attrs, $_; 73 push @attrs, $_;
61 } 74 }
62 } 75 }
63 return $old ? $old->($package, $ref, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
64 }; 77 };
65 } 78 }
66 79
67 sub INIT {
68 &async(pop @async) while @async;
69 }
70} 80}
71 81
72=item $main 82=item $main
73 83
74This coroutine represents the main program. 84This coroutine represents the main program.
… …
103our $idle = new Coro sub { 113our $idle = new Coro sub {
104 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
105 exit(51); 115 exit(51);
106}; 116};
107 117
108# we really need priorities... 118# this coroutine is necessary because a coroutine
109my @ready; # the ready queue. hehe, rather broken ;) 119# cannot destroy itself.
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};
110 138
111# static methods. not really. 139# static methods. not really.
112 140
113=head2 STATIC METHODS 141=head2 STATIC METHODS
114 142
… …
132 160
133=cut 161=cut
134 162
135sub async(&@) { 163sub async(&@) {
136 my $pid = new Coro @_; 164 my $pid = new Coro @_;
165 $manager->ready; # this ensures that the stack is cloned from the manager
137 $pid->ready; 166 $pid->ready;
138 $pid; 167 $pid;
139} 168}
140 169
141=item schedule 170=item schedule
… …
144into the ready queue, so calling this function usually means you will 173into the ready queue, so calling this function usually means you will
145never be called again. 174never be called again.
146 175
147=cut 176=cut
148 177
149my $prev;
150
151sub schedule {
152 # should be done using priorities :(
153 ($prev, $current) = ($current, shift @ready || $idle);
154 Coro::State::transfer($prev, $current);
155}
156
157=item yield 178=item cede
158 179
159Yield to other processes. This function puts the current process into the 180"Cede" to other processes. This function puts the current process into the
160ready 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.
161 183
162=cut 184=cut
163 185
164sub 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} = [@_];
165 $current->ready; 196 $current->cancel;
166 &schedule; 197 &schedule;
167} 198 die; # NORETURN
168
169=item terminate
170
171Terminates the current process.
172
173Future versions of this function will allow result arguments.
174
175=cut
176
177sub terminate {
178 $current->{_results} = [@_];
179 &schedule;
180} 199}
181 200
182=back 201=back
183 202
184# dynamic methods 203# dynamic methods
… …
190=over 4 209=over 4
191 210
192=item new Coro \&sub [, @args...] 211=item new Coro \&sub [, @args...]
193 212
194Create 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
195automatically 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
196the ready queue by calling the ready method. 216by calling the ready method.
197
198The coderef you submit MUST NOT be a closure that refers to variables
199in an outer scope. This does NOT work. Pass arguments into it instead.
200 217
201=cut 218=cut
202 219
203sub _newcoro { 220sub _newcoro {
204 terminate &{+shift}; 221 terminate &{+shift};
… …
211 }, $class; 228 }, $class;
212} 229}
213 230
214=item $process->ready 231=item $process->ready
215 232
216Put the current process into the ready queue. 233Put the given process into the ready queue.
217 234
218=cut 235=cut
219 236
220sub ready { 237=item $process->cancel
238
239Like C<terminate>, but terminates the specified process instead.
240
241=cut
242
243sub cancel {
221 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;
222} 318}
223 319
224=back 320=back
225 321
226=cut 322=cut
227 323
2281; 3241;
229 325
230=head1 BUGS/LIMITATIONS 326=head1 BUGS/LIMITATIONS
231 327
232 - could be faster, especially when the core would introduce special 328 - you must make very sure that no coro is still active on global destruction.
233 support for coroutines (like it does for threads). 329 very bad things might happen otherwise (usually segfaults).
234 - there is still a memleak on coroutine termination that I could not
235 identify. Could be as small as a single SV.
236 - this module is not well-tested.
237 - if variables or arguments "disappear" (become undef) or become
238 corrupted please contact the author so he cen iron out the
239 remaining bugs.
240 - this module is not thread-safe. You must only ever use this module from 330 - this module is not thread-safe. You must only ever use this module from
241 the same thread (this requirement might be loosened in the future to 331 the same thread (this requirement might be loosened in the future to
242 allow per-thread schedulers, but Coro::State does not yet allow this). 332 allow per-thread schedulers, but Coro::State does not yet allow this).
243 333
244=head1 SEE ALSO 334=head1 SEE ALSO
245 335
246L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 336L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
247L<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>.
248 339
249=head1 AUTHOR 340=head1 AUTHOR
250 341
251 Marc Lehmann <pcg@goof.com> 342 Marc Lehmann <pcg@goof.com>
252 http://www.goof.com/pcg/marc/ 343 http://www.goof.com/pcg/marc/

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