ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/Coro/Coro.pm
(Generate patch)

Comparing Coro/Coro.pm (file contents):
Revision 1.13 by root, Tue Jul 17 00:24:14 2001 UTC vs.
Revision 1.75 by root, Wed Jan 25 21:43:58 2006 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
26In this module, coroutines are defined as "callchain + lexical variables
27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
30
23=cut 31=cut
24 32
25package Coro; 33package Coro;
26 34
35use strict;
36no warnings "uninitialized";
37
27use Coro::State; 38use Coro::State;
28 39
29use base Exporter; 40use base Exporter::;
30 41
31$VERSION = 0.05; 42our $idle; # idle coroutine
43our $main; # main coroutine
44our $current; # current coroutine
32 45
46our $VERSION = 1.8;
47
33@EXPORT = qw(async yield schedule terminate); 48our @EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 49our %EXPORT_TAGS = (
50 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
51);
52our @EXPORT_OK = @{$EXPORT_TAGS{prio}};
35 53
36{ 54{
37 use subs 'async';
38
39 my @async; 55 my @async;
56 my $init;
40 57
41 # this way of handling attributes simply is NOT scalable ;() 58 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 59 sub import {
60 no strict 'refs';
61
43 Coro->export_to_level(1, @_); 62 Coro->export_to_level(1, @_);
63
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 64 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
45 *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { 65 *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
46 my ($package, $ref) = (shift, shift); 66 my ($package, $ref) = (shift, shift);
47 my @attrs; 67 my @attrs;
48 for (@_) { 68 for (@_) {
49 if ($_ eq "Coro") { 69 if ($_ eq "Coro") {
50 push @async, $ref; 70 push @async, $ref;
71 unless ($init++) {
72 eval q{
73 sub INIT {
74 &async(pop @async) while @async;
75 }
76 };
77 }
51 } else { 78 } else {
52 push @attrs, @_; 79 push @attrs, $_;
53 } 80 }
54 } 81 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 82 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 83 };
57 } 84 }
58 85
59 sub INIT {
60 async pop @async while @async;
61 }
62} 86}
87
88=over 4
63 89
64=item $main 90=item $main
65 91
66This coroutine represents the main program. 92This coroutine represents the main program.
67 93
68=cut 94=cut
69 95
70our $main = new Coro; 96$main = new Coro;
71 97
72=item $current 98=item $current (or as function: current)
73 99
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 100The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 101
76=cut 102=cut
77 103
78# maybe some other module used Coro::Specific before... 104# maybe some other module used Coro::Specific before...
79if ($current) { 105if ($current) {
80 $main->{specific} = $current->{specific}; 106 $main->{specific} = $current->{specific};
81} 107}
82 108
83our $current = $main; 109$current = $main;
110
111sub current() { $current }
84 112
85=item $idle 113=item $idle
86 114
87The coroutine to switch to when no other coroutine is running. The default 115The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 116implementation prints "FATAL: deadlock detected" and exits.
89 117
90=cut 118=cut
91 119
92# should be done using priorities :( 120# should be done using priorities :(
93our $idle = new Coro sub { 121$idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 122 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 123 exit(51);
96}; 124};
97 125
98# we really need priorities... 126# this coroutine is necessary because a coroutine
99## my @ready; #d# 127# cannot destroy itself.
100our @ready = (); # the ready queue. hehe, rather broken ;) 128my @destroy;
129my $manager;
130$manager = new Coro sub {
131 while () {
132 # by overwriting the state object with the manager we destroy it
133 # while still being able to schedule this coroutine (in case it has
134 # been readied multiple times. this is harmless since the manager
135 # can be called as many times as neccessary and will always
136 # remove itself from the runqueue
137 while (@destroy) {
138 my $coro = pop @destroy;
139 $coro->{status} ||= [];
140 $_->ready for @{delete $coro->{join} || []};
141
142 # the next line destroys the _coro_state, but keeps the
143 # process itself intact (we basically make it a zombie
144 # process that always runs the manager thread, so it's possible
145 # to transfer() to this process).
146 $coro->{_coro_state} = $manager->{_coro_state};
147 }
148 &schedule;
149 }
150};
101 151
102# static methods. not really. 152# static methods. not really.
153
154=back
103 155
104=head2 STATIC METHODS 156=head2 STATIC METHODS
105 157
106Static methods are actually functions that operate on the current process only. 158Static methods are actually functions that operate on the current process only.
107 159
… …
116 # create a new coroutine that just prints its arguments 168 # create a new coroutine that just prints its arguments
117 async { 169 async {
118 print "@_\n"; 170 print "@_\n";
119 } 1,2,3,4; 171 } 1,2,3,4;
120 172
121The coderef you submit MUST NOT be a closure that refers to variables
122in an outer scope. This does NOT work. Pass arguments into it instead.
123
124=cut 173=cut
125 174
126sub async(&@) { 175sub async(&@) {
127 my $pid = new Coro @_; 176 my $pid = new Coro @_;
177 $manager->ready; # this ensures that the stack is cloned from the manager
128 $pid->ready; 178 $pid->ready;
129 $pid; 179 $pid;
130} 180}
131 181
132=item schedule 182=item schedule
… …
135into the ready queue, so calling this function usually means you will 185into the ready queue, so calling this function usually means you will
136never be called again. 186never be called again.
137 187
138=cut 188=cut
139 189
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 190=item cede
149 191
150Yield to other processes. This function puts the current process into the 192"Cede" to other processes. This function puts the current process into the
151ready queue and calls C<schedule>. 193ready queue and calls C<schedule>, which has the effect of giving up the
194current "timeslice" to other coroutines of the same or higher priority.
152 195
153=cut 196=cut
154 197
155sub yield {
156 $current->ready;
157 &schedule;
158}
159
160=item terminate 198=item terminate [arg...]
161 199
162Terminates the current process. 200Terminates the current process with the given status values (see L<cancel>).
163
164Future versions of this function will allow result arguments.
165 201
166=cut 202=cut
167 203
168sub terminate { 204sub terminate {
169 $current->{_results} = [@_]; 205 $current->cancel (@_);
170 &schedule;
171} 206}
172 207
173=back 208=back
174 209
175# dynamic methods 210# dynamic methods
… …
181=over 4 216=over 4
182 217
183=item new Coro \&sub [, @args...] 218=item new Coro \&sub [, @args...]
184 219
185Create a new process and return it. When the sub returns the process 220Create a new process and return it. When the sub returns the process
186automatically terminates. To start the process you must first put it into 221automatically terminates as if C<terminate> with the returned values were
222called. To make the process run you must first put it into the ready queue
187the ready queue by calling the ready method. 223by 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.
191 224
192=cut 225=cut
193 226
194sub _newcoro { 227sub _newcoro {
195 terminate &{+shift}; 228 terminate &{+shift};
… …
202 }, $class; 235 }, $class;
203} 236}
204 237
205=item $process->ready 238=item $process->ready
206 239
207Put the current process into the ready queue. 240Put the given process into the ready queue.
208 241
209=cut 242=cut
210 243
211sub ready { 244=item $process->cancel (arg...)
212 push @ready, $_[0]; 245
246Temrinates the given process and makes it return the given arguments as
247status (default: the empty list).
248
249=cut
250
251sub cancel {
252 my $self = shift;
253 $self->{status} = [@_];
254 push @destroy, $self;
255 $manager->ready;
256 &schedule if $current == $self;
257}
258
259=item $process->join
260
261Wait until the coroutine terminates and return any values given to the
262C<terminate> or C<cancel> functions. C<join> can be called multiple times
263from multiple processes.
264
265=cut
266
267sub join {
268 my $self = shift;
269 unless ($self->{status}) {
270 push @{$self->{join}}, $current;
271 &schedule;
272 }
273 wantarray ? @{$self->{status}} : $self->{status}[0];
274}
275
276=item $oldprio = $process->prio($newprio)
277
278Sets (or gets, if the argument is missing) the priority of the
279process. Higher priority processes get run before lower priority
280processes. Priorities are small signed integers (currently -4 .. +3),
281that you can refer to using PRIO_xxx constants (use the import tag :prio
282to get then):
283
284 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
285 3 > 1 > 0 > -1 > -3 > -4
286
287 # set priority to HIGH
288 current->prio(PRIO_HIGH);
289
290The idle coroutine ($Coro::idle) always has a lower priority than any
291existing coroutine.
292
293Changing the priority of the current process will take effect immediately,
294but changing the priority of processes in the ready queue (but not
295running) will only take effect after the next schedule (of that
296process). This is a bug that will be fixed in some future version.
297
298=cut
299
300sub prio {
301 my $old = $_[0]{prio};
302 $_[0]{prio} = $_[1] if @_ > 1;
303 $old;
304}
305
306=item $newprio = $process->nice($change)
307
308Similar to C<prio>, but subtract the given value from the priority (i.e.
309higher values mean lower priority, just as in unix).
310
311=cut
312
313sub nice {
314 $_[0]{prio} -= $_[1];
315}
316
317=item $olddesc = $process->desc($newdesc)
318
319Sets (or gets in case the argument is missing) the description for this
320process. This is just a free-form string you can associate with a process.
321
322=cut
323
324sub desc {
325 my $old = $_[0]{desc};
326 $_[0]{desc} = $_[1] if @_ > 1;
327 $old;
213} 328}
214 329
215=back 330=back
216 331
217=cut 332=cut
218 333
2191; 3341;
220 335
336=head1 BUGS/LIMITATIONS
337
338 - you must make very sure that no coro is still active on global
339 destruction. very bad things might happen otherwise (usually segfaults).
340
341 - this module is not thread-safe. You should only ever use this module
342 from the same thread (this requirement might be losened in the future
343 to allow per-thread schedulers, but Coro::State does not yet allow
344 this).
345
221=head1 SEE ALSO 346=head1 SEE ALSO
222 347
223L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 348Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
224L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 349
350Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
351
352Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
353
354Embedding: L<Coro:MakeMaker>
225 355
226=head1 AUTHOR 356=head1 AUTHOR
227 357
228 Marc Lehmann <pcg@goof.com> 358 Marc Lehmann <schmorp@schmorp.de>
229 http://www.goof.com/pcg/marc/ 359 http://home.schmorp.de/
230 360
231=cut 361=cut
232 362

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines