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Comparing Coro/Coro.pm (file contents):
Revision 1.17 by root, Thu Jul 19 02:45:09 2001 UTC vs.
Revision 1.53 by root, Tue May 27 01:15:26 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 = 0.08; 41$VERSION = 0.7;
37 42
38@EXPORT = qw(async yield schedule terminate); 43@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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, $ref, @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
104my @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};
105 138
106# static methods. not really. 139# static methods. not really.
140
141=back
107 142
108=head2 STATIC METHODS 143=head2 STATIC METHODS
109 144
110Static methods are actually functions that operate on the current process only. 145Static methods are actually functions that operate on the current process only.
111 146
… …
127 162
128=cut 163=cut
129 164
130sub async(&@) { 165sub async(&@) {
131 my $pid = new Coro @_; 166 my $pid = new Coro @_;
167 $manager->ready; # this ensures that the stack is cloned from the manager
132 $pid->ready; 168 $pid->ready;
133 $pid; 169 $pid;
134} 170}
135 171
136=item schedule 172=item schedule
… …
139into the ready queue, so calling this function usually means you will 175into the ready queue, so calling this function usually means you will
140never be called again. 176never be called again.
141 177
142=cut 178=cut
143 179
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 180=item cede
153 181
154Yield to other processes. This function puts the current process into the 182"Cede" to other processes. This function puts the current process into the
155ready 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.
156 185
157=cut 186=cut
158 187
159sub 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} = [@_];
160 $current->ready; 198 $current->cancel;
161 &schedule; 199 &schedule;
162} 200 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} 201}
176 202
177=back 203=back
178 204
179# dynamic methods 205# dynamic methods
… …
185=over 4 211=over 4
186 212
187=item new Coro \&sub [, @args...] 213=item new Coro \&sub [, @args...]
188 214
189Create 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
190automatically 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
191the ready queue by calling the ready method. 218by 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.
195 219
196=cut 220=cut
197 221
198sub _newcoro { 222sub _newcoro {
199 terminate &{+shift}; 223 terminate &{+shift};
… …
206 }, $class; 230 }, $class;
207} 231}
208 232
209=item $process->ready 233=item $process->ready
210 234
211Put the current process into the ready queue. 235Put the given process into the ready queue.
212 236
213=cut 237=cut
214 238
215sub ready { 239=item $process->cancel
240
241Like C<terminate>, but terminates the specified process instead.
242
243=cut
244
245sub cancel {
216 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;
217} 320}
218 321
219=back 322=back
220 323
221=cut 324=cut
222 325
2231; 3261;
224 327
225=head1 BUGS/LIMITATIONS 328=head1 BUGS/LIMITATIONS
226 329
227 - could be faster, especially when the core would introduce special 330 - you must make very sure that no coro is still active on global
228 support for coroutines (like it does for threads). 331 destruction. very bad things might happen otherwise (usually segfaults).
229 - there is still a memleak on coroutine termination that I could not 332
230 identify. Could be as small as a single SV.
231 - this module is not well-tested.
232 - if variables or arguments "disappear" (become undef) or become
233 corrupted please contact the author so he cen iron out the
234 remaining bugs.
235 - this module is not thread-safe. You must only ever use this module from 333 - this module is not thread-safe. You should only ever use this module
236 the same thread (this requirement might be loosened in the future to 334 from the same thread (this requirement might be losened in the future
237 allow per-thread schedulers, but Coro::Satte does not yet allow this). 335 to allow per-thread schedulers, but Coro::State does not yet allow
336 this).
238 337
239=head1 SEE ALSO 338=head1 SEE ALSO
240 339
241L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 340L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
242L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 341L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
342L<Coro::Handle>, L<Coro::Socket>.
243 343
244=head1 AUTHOR 344=head1 AUTHOR
245 345
246 Marc Lehmann <pcg@goof.com> 346 Marc Lehmann <pcg@goof.com>
247 http://www.goof.com/pcg/marc/ 347 http://www.goof.com/pcg/marc/

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