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Comparing Coro/Coro.pm (file contents):
Revision 1.19 by root, Sat Jul 21 03:44:06 2001 UTC vs.
Revision 1.56 by pcg, Sat Nov 15 03:53:10 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
27 30
28=cut 31=cut
29 32
30package Coro; 33package Coro;
31 34
35BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
36
32use Coro::State; 37use Coro::State;
33 38
39use vars qw($idle $main $current);
40
34use base Exporter; 41use base Exporter;
35 42
36$VERSION = 0.09; 43$VERSION = "0.9";
37 44
38@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}};
40 50
41{ 51{
42 use subs 'async';
43
44 my @async; 52 my @async;
53 my $init;
45 54
46 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 56 sub import {
48 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
51 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
52 my @attrs; 61 my @attrs;
53 for (@_) { 62 for (@_) {
54 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
55 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 }
56 } else { 72 } else {
57 push @attrs, $_; 73 push @attrs, $_;
58 } 74 }
59 } 75 }
60 return $old ? $old->($package, $ref, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 77 };
62 } 78 }
63 79
64 sub INIT {
65 async pop @async while @async;
66 }
67} 80}
81
82=over 4
68 83
69=item $main 84=item $main
70 85
71This coroutine represents the main program. 86This coroutine represents the main program.
72 87
73=cut 88=cut
74 89
75our $main = new Coro; 90$main = new Coro;
76 91
77=item $current (or as function: current) 92=item $current (or as function: current)
78 93
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 94The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 95
… …
83# maybe some other module used Coro::Specific before... 98# maybe some other module used Coro::Specific before...
84if ($current) { 99if ($current) {
85 $main->{specific} = $current->{specific}; 100 $main->{specific} = $current->{specific};
86} 101}
87 102
88our $current = $main; 103$current = $main;
89 104
90sub current() { $current } 105sub current() { $current }
91 106
92=item $idle 107=item $idle
93 108
… …
95implementation prints "FATAL: deadlock detected" and exits. 110implementation prints "FATAL: deadlock detected" and exits.
96 111
97=cut 112=cut
98 113
99# should be done using priorities :( 114# should be done using priorities :(
100our $idle = new Coro sub { 115$idle = new Coro sub {
101 print STDERR "FATAL: deadlock detected\n"; 116 print STDERR "FATAL: deadlock detected\n";
102 exit(51); 117 exit(51);
103}; 118};
104 119
105# we really need priorities... 120# this coroutine is necessary because a coroutine
106my @ready; # the ready queue. hehe, rather broken ;) 121# cannot destroy itself.
122my @destroy;
123my $manager;
124$manager = new Coro sub {
125 while() {
126 # by overwriting the state object with the manager we destroy it
127 # while still being able to schedule this coroutine (in case it has
128 # been readied multiple times. this is harmless since the manager
129 # can be called as many times as neccessary and will always
130 # remove itself from the runqueue
131 while (@destroy) {
132 my $coro = pop @destroy;
133 $coro->{status} ||= [];
134 $_->ready for @{delete $coro->{join} || []};
135 $coro->{_coro_state} = $manager->{_coro_state};
136 }
137 &schedule;
138 }
139};
107 140
108# static methods. not really. 141# static methods. not really.
142
143=back
109 144
110=head2 STATIC METHODS 145=head2 STATIC METHODS
111 146
112Static methods are actually functions that operate on the current process only. 147Static methods are actually functions that operate on the current process only.
113 148
… …
129 164
130=cut 165=cut
131 166
132sub async(&@) { 167sub async(&@) {
133 my $pid = new Coro @_; 168 my $pid = new Coro @_;
169 $manager->ready; # this ensures that the stack is cloned from the manager
134 $pid->ready; 170 $pid->ready;
135 $pid; 171 $pid;
136} 172}
137 173
138=item schedule 174=item schedule
… …
141into the ready queue, so calling this function usually means you will 177into the ready queue, so calling this function usually means you will
142never be called again. 178never be called again.
143 179
144=cut 180=cut
145 181
146my $prev;
147
148sub schedule {
149 # should be done using priorities :(
150 ($prev, $current) = ($current, shift @ready || $idle);
151 Coro::State::transfer($prev, $current);
152}
153
154=item yield 182=item cede
155 183
156Yield to other processes. This function puts the current process into the 184"Cede" to other processes. This function puts the current process into the
157ready queue and calls C<schedule>. 185ready queue and calls C<schedule>, which has the effect of giving up the
186current "timeslice" to other coroutines of the same or higher priority.
158 187
159=cut 188=cut
160 189
161sub yield { 190=item terminate [arg...]
191
192Terminates the current process.
193
194Future versions of this function will allow result arguments.
195
196=cut
197
198sub terminate {
199 $current->{status} = [@_];
162 $current->ready; 200 $current->cancel;
163 &schedule; 201 &schedule;
164} 202 die; # NORETURN
165
166=item terminate
167
168Terminates the current process.
169
170Future versions of this function will allow result arguments.
171
172=cut
173
174sub terminate {
175 $current->{_results} = [@_];
176 &schedule;
177} 203}
178 204
179=back 205=back
180 206
181# dynamic methods 207# dynamic methods
… …
187=over 4 213=over 4
188 214
189=item new Coro \&sub [, @args...] 215=item new Coro \&sub [, @args...]
190 216
191Create a new process and return it. When the sub returns the process 217Create a new process and return it. When the sub returns the process
192automatically terminates. To start the process you must first put it into 218automatically terminates as if C<terminate> with the returned values were
219called. To make the process run you must first put it into the ready queue
193the ready queue by calling the ready method. 220by calling the ready method.
194
195The coderef you submit MUST NOT be a closure that refers to variables
196in an outer scope. This does NOT work. Pass arguments into it instead.
197 221
198=cut 222=cut
199 223
200sub _newcoro { 224sub _newcoro {
201 terminate &{+shift}; 225 terminate &{+shift};
… …
208 }, $class; 232 }, $class;
209} 233}
210 234
211=item $process->ready 235=item $process->ready
212 236
213Put the current process into the ready queue. 237Put the given process into the ready queue.
214 238
215=cut 239=cut
216 240
217sub ready { 241=item $process->cancel
242
243Like C<terminate>, but terminates the specified process instead.
244
245=cut
246
247sub cancel {
218 push @ready, $_[0]; 248 push @destroy, $_[0];
249 $manager->ready;
250 &schedule if $current == $_[0];
251}
252
253=item $process->join
254
255Wait until the coroutine terminates and return any values given to the
256C<terminate> function. C<join> can be called multiple times from multiple
257processes.
258
259=cut
260
261sub join {
262 my $self = shift;
263 unless ($self->{status}) {
264 push @{$self->{join}}, $current;
265 &schedule;
266 }
267 wantarray ? @{$self->{status}} : $self->{status}[0];
268}
269
270=item $oldprio = $process->prio($newprio)
271
272Sets (or gets, if the argument is missing) the priority of the
273process. Higher priority processes get run before lower priority
274processes. Priorities are small signed integers (currently -4 .. +3),
275that you can refer to using PRIO_xxx constants (use the import tag :prio
276to get then):
277
278 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
279 3 > 1 > 0 > -1 > -3 > -4
280
281 # set priority to HIGH
282 current->prio(PRIO_HIGH);
283
284The idle coroutine ($Coro::idle) always has a lower priority than any
285existing coroutine.
286
287Changing the priority of the current process will take effect immediately,
288but changing the priority of processes in the ready queue (but not
289running) will only take effect after the next schedule (of that
290process). This is a bug that will be fixed in some future version.
291
292=cut
293
294sub prio {
295 my $old = $_[0]{prio};
296 $_[0]{prio} = $_[1] if @_ > 1;
297 $old;
298}
299
300=item $newprio = $process->nice($change)
301
302Similar to C<prio>, but subtract the given value from the priority (i.e.
303higher values mean lower priority, just as in unix).
304
305=cut
306
307sub nice {
308 $_[0]{prio} -= $_[1];
309}
310
311=item $olddesc = $process->desc($newdesc)
312
313Sets (or gets in case the argument is missing) the description for this
314process. This is just a free-form string you can associate with a process.
315
316=cut
317
318sub desc {
319 my $old = $_[0]{desc};
320 $_[0]{desc} = $_[1] if @_ > 1;
321 $old;
219} 322}
220 323
221=back 324=back
222 325
223=cut 326=cut
224 327
2251; 3281;
226 329
227=head1 BUGS/LIMITATIONS 330=head1 BUGS/LIMITATIONS
228 331
229 - could be faster, especially when the core would introduce special 332 - you must make very sure that no coro is still active on global
230 support for coroutines (like it does for threads). 333 destruction. very bad things might happen otherwise (usually segfaults).
231 - there is still a memleak on coroutine termination that I could not 334
232 identify. Could be as small as a single SV.
233 - this module is not well-tested.
234 - if variables or arguments "disappear" (become undef) or become
235 corrupted please contact the author so he cen iron out the
236 remaining bugs.
237 - this module is not thread-safe. You must only ever use this module from 335 - this module is not thread-safe. You should only ever use this module
238 the same thread (this requirement might be loosened in the future to 336 from the same thread (this requirement might be losened in the future
239 allow per-thread schedulers, but Coro::Satte does not yet allow this). 337 to allow per-thread schedulers, but Coro::State does not yet allow
338 this).
240 339
241=head1 SEE ALSO 340=head1 SEE ALSO
242 341
243L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 342L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
244L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 343L<Coro::Signal>, L<Coro::State>, L<Coro::Timer>, L<Coro::Event>,
344L<Coro::L<Coro::RWLock>, Handle>, L<Coro::Socket>.
245 345
246=head1 AUTHOR 346=head1 AUTHOR
247 347
248 Marc Lehmann <pcg@goof.com> 348 Marc Lehmann <pcg@goof.com>
249 http://www.goof.com/pcg/marc/ 349 http://www.goof.com/pcg/marc/

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