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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 1.82 by root, Fri Nov 24 13:40:36 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 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
27 30
28=cut 31=cut
29 32
30package Coro; 33package Coro;
31 34
35use strict;
36no warnings "uninitialized";
37
32use Coro::State; 38use Coro::State;
33 39
34use base Exporter; 40use base Exporter::;
35 41
36$VERSION = 0.09; 42our $idle; # idle coroutine
43our $main; # main coroutine
44our $current; # current coroutine
37 45
46our $VERSION = '2.5';
47
38@EXPORT = qw(async yield schedule terminate current); 48our @EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}};
40 53
41{ 54{
42 use subs 'async';
43
44 my @async; 55 my @async;
56 my $init;
45 57
46 # this way of handling attributes simply is NOT scalable ;() 58 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 59 sub import {
60 no strict 'refs';
61
48 Coro->export_to_level(1, @_); 62 Coro->export_to_level(1, @_);
63
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 64 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
50 *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { 65 *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
51 my ($package, $ref) = (shift, shift); 66 my ($package, $ref) = (shift, shift);
52 my @attrs; 67 my @attrs;
53 for (@_) { 68 for (@_) {
54 if ($_ eq "Coro") { 69 if ($_ eq "Coro") {
55 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 }
56 } else { 78 } else {
57 push @attrs, $_; 79 push @attrs, $_;
58 } 80 }
59 } 81 }
60 return $old ? $old->($package, $ref, @attrs) : @attrs; 82 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 83 };
62 } 84 }
63 85
64 sub INIT {
65 async pop @async while @async;
66 }
67} 86}
87
88=over 4
68 89
69=item $main 90=item $main
70 91
71This coroutine represents the main program. 92This coroutine represents the main program.
72 93
73=cut 94=cut
74 95
75our $main = new Coro; 96$main = new Coro;
76 97
77=item $current (or as function: current) 98=item $current (or as function: current)
78 99
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 100The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 101
… …
83# maybe some other module used Coro::Specific before... 104# maybe some other module used Coro::Specific before...
84if ($current) { 105if ($current) {
85 $main->{specific} = $current->{specific}; 106 $main->{specific} = $current->{specific};
86} 107}
87 108
88our $current = $main; 109$current = $main;
89 110
90sub current() { $current } 111sub current() { $current }
91 112
92=item $idle 113=item $idle
93 114
… …
95implementation prints "FATAL: deadlock detected" and exits. 116implementation prints "FATAL: deadlock detected" and exits.
96 117
97=cut 118=cut
98 119
99# should be done using priorities :( 120# should be done using priorities :(
100our $idle = new Coro sub { 121$idle = new Coro sub {
101 print STDERR "FATAL: deadlock detected\n"; 122 print STDERR "FATAL: deadlock detected\n";
102 exit(51); 123 exit(51);
103}; 124};
104 125
105# we really need priorities... 126# this coroutine is necessary because a coroutine
106my @ready; # the ready queue. hehe, rather broken ;) 127# cannot destroy itself.
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 $coro->{_coro_state}->_clone_state_from ($manager->{_coro_state});
147 }
148 &schedule;
149 }
150};
107 151
108# static methods. not really. 152# static methods. not really.
153
154=back
109 155
110=head2 STATIC METHODS 156=head2 STATIC METHODS
111 157
112Static methods are actually functions that operate on the current process only. 158Static methods are actually functions that operate on the current process only.
113 159
… …
116=item async { ... } [@args...] 162=item async { ... } [@args...]
117 163
118Create a new asynchronous process and return it's process object 164Create a new asynchronous process and return it's process object
119(usually unused). When the sub returns the new process is automatically 165(usually unused). When the sub returns the new process is automatically
120terminated. 166terminated.
167
168When the coroutine dies, the program will exit, just as in the main
169program.
121 170
122 # create a new coroutine that just prints its arguments 171 # create a new coroutine that just prints its arguments
123 async { 172 async {
124 print "@_\n"; 173 print "@_\n";
125 } 1,2,3,4; 174 } 1,2,3,4;
126 175
127The coderef you submit MUST NOT be a closure that refers to variables
128in an outer scope. This does NOT work. Pass arguments into it instead.
129
130=cut 176=cut
131 177
132sub async(&@) { 178sub async(&@) {
133 my $pid = new Coro @_; 179 my $pid = new Coro @_;
180 $manager->ready; # this ensures that the stack is cloned from the manager
134 $pid->ready; 181 $pid->ready;
135 $pid; 182 $pid;
136} 183}
137 184
138=item schedule 185=item schedule
… …
141into the ready queue, so calling this function usually means you will 188into the ready queue, so calling this function usually means you will
142never be called again. 189never be called again.
143 190
144=cut 191=cut
145 192
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 193=item cede
155 194
156Yield to other processes. This function puts the current process into the 195"Cede" to other processes. This function puts the current process into the
157ready queue and calls C<schedule>. 196ready queue and calls C<schedule>, which has the effect of giving up the
197current "timeslice" to other coroutines of the same or higher priority.
158 198
159=cut 199=cut
160 200
161sub yield {
162 $current->ready;
163 &schedule;
164}
165
166=item terminate 201=item terminate [arg...]
167 202
168Terminates the current process. 203Terminates the current process with the given status values (see L<cancel>).
169
170Future versions of this function will allow result arguments.
171 204
172=cut 205=cut
173 206
174sub terminate { 207sub terminate {
175 $current->{_results} = [@_]; 208 $current->cancel (@_);
176 &schedule;
177} 209}
178 210
179=back 211=back
180 212
181# dynamic methods 213# dynamic methods
… …
187=over 4 219=over 4
188 220
189=item new Coro \&sub [, @args...] 221=item new Coro \&sub [, @args...]
190 222
191Create a new process and return it. When the sub returns the process 223Create a new process and return it. When the sub returns the process
192automatically terminates. To start the process you must first put it into 224automatically terminates as if C<terminate> with the returned values were
225called. To make the process run you must first put it into the ready queue
193the ready queue by calling the ready method. 226by 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.
197 227
198=cut 228=cut
199 229
200sub _newcoro { 230sub _newcoro {
201 terminate &{+shift}; 231 terminate &{+shift};
202} 232}
203 233
204sub new { 234sub new {
205 my $class = shift; 235 my $class = shift;
206 bless { 236 bless {
207 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_), 237 _coro_state => (new Coro::State \&_newcoro, @_),
208 }, $class; 238 }, $class;
209} 239}
210 240
211=item $process->ready 241=item $process->ready
212 242
213Put the current process into the ready queue. 243Put the given process into the ready queue.
214 244
215=cut 245=cut
216 246
217sub ready { 247=item $process->cancel (arg...)
218 push @ready, $_[0]; 248
249Terminates the given process and makes it return the given arguments as
250status (default: the empty list).
251
252=cut
253
254sub cancel {
255 my $self = shift;
256 $self->{status} = [@_];
257 push @destroy, $self;
258 $manager->ready;
259 &schedule if $current == $self;
260}
261
262=item $process->join
263
264Wait until the coroutine terminates and return any values given to the
265C<terminate> or C<cancel> functions. C<join> can be called multiple times
266from multiple processes.
267
268=cut
269
270sub join {
271 my $self = shift;
272 unless ($self->{status}) {
273 push @{$self->{join}}, $current;
274 &schedule;
275 }
276 wantarray ? @{$self->{status}} : $self->{status}[0];
277}
278
279=item $oldprio = $process->prio ($newprio)
280
281Sets (or gets, if the argument is missing) the priority of the
282process. Higher priority processes get run before lower priority
283processes. Priorities are small signed integers (currently -4 .. +3),
284that you can refer to using PRIO_xxx constants (use the import tag :prio
285to get then):
286
287 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
288 3 > 1 > 0 > -1 > -3 > -4
289
290 # set priority to HIGH
291 current->prio(PRIO_HIGH);
292
293The idle coroutine ($Coro::idle) always has a lower priority than any
294existing coroutine.
295
296Changing the priority of the current process will take effect immediately,
297but changing the priority of processes in the ready queue (but not
298running) will only take effect after the next schedule (of that
299process). This is a bug that will be fixed in some future version.
300
301=cut
302
303sub prio {
304 shift->{_coro_state}->prio (@_)
305}
306
307=item $newprio = $process->nice ($change)
308
309Similar to C<prio>, but subtract the given value from the priority (i.e.
310higher values mean lower priority, just as in unix).
311
312=cut
313
314sub nice {
315 shift->{_coro_state}->nice (@_)
316}
317
318=item $olddesc = $process->desc ($newdesc)
319
320Sets (or gets in case the argument is missing) the description for this
321process. This is just a free-form string you can associate with a process.
322
323=cut
324
325sub desc {
326 my $old = $_[0]{desc};
327 $_[0]{desc} = $_[1] if @_ > 1;
328 $old;
219} 329}
220 330
221=back 331=back
222 332
223=cut 333=cut
224 334
2251; 3351;
226 336
227=head1 BUGS/LIMITATIONS 337=head1 BUGS/LIMITATIONS
228 338
229 - could be faster, especially when the core would introduce special 339 - you must make very sure that no coro is still active on global
230 support for coroutines (like it does for threads). 340 destruction. very bad things might happen otherwise (usually segfaults).
231 - there is still a memleak on coroutine termination that I could not 341
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 342 - 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 343 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). 344 to allow per-thread schedulers, but Coro::State does not yet allow
345 this).
240 346
241=head1 SEE ALSO 347=head1 SEE ALSO
242 348
243L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 349Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
244L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 350
351Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
352
353Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
354
355Embedding: L<Coro:MakeMaker>
245 356
246=head1 AUTHOR 357=head1 AUTHOR
247 358
248 Marc Lehmann <pcg@goof.com> 359 Marc Lehmann <schmorp@schmorp.de>
249 http://www.goof.com/pcg/marc/ 360 http://home.schmorp.de/
250 361
251=cut 362=cut
252 363

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