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Comparing Coro/Coro.pm (file contents):
Revision 1.9 by root, Sun Jul 15 02:35:52 2001 UTC vs.
Revision 1.78 by root, Wed Nov 1 01:21:21 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 = 0.04; 42our $idle; # idle coroutine
43our $main; # main coroutine
44our $current; # current coroutine
32 45
33@EXPORT = qw(async yield schedule); 46our $VERSION = '2.1';
34@EXPORT_OK = qw($current); 47
48our @EXPORT = qw(async cede schedule terminate 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
99my @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} = $manager->{_coro_state};
147 }
148 &schedule;
149 }
150};
100 151
101# static methods. not really. 152# static methods. not really.
102 153
154=back
155
103=head2 STATIC METHODS 156=head2 STATIC METHODS
104 157
105Static methods are actually functions that operate on the current process only. 158Static methods are actually functions that operate on the current process only.
106 159
107=over 4 160=over 4
108 161
109=item async { ... }; 162=item async { ... } [@args...]
110 163
111Create a new asynchronous process and return it's process object 164Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 165(usually unused). When the sub returns the new process is automatically
113terminated. 166terminated.
114 167
115=cut 168 # create a new coroutine that just prints its arguments
169 async {
170 print "@_\n";
171 } 1,2,3,4;
116 172
173=cut
174
117sub async(&) { 175sub async(&@) {
118 (new Coro $_[0])->ready; 176 my $pid = new Coro @_;
177 $manager->ready; # this ensures that the stack is cloned from the manager
178 $pid->ready;
179 $pid;
119} 180}
120 181
121=item schedule 182=item schedule
122 183
123Calls the scheduler. Please note that the current process will not be put 184Calls the scheduler. Please note that the current process will not be put
124into the ready queue, so calling this function usually means you will 185into the ready queue, so calling this function usually means you will
125never be called again. 186never be called again.
126 187
127=cut 188=cut
128 189
129my $prev;
130
131sub schedule {
132 # should be done using priorities :(
133 ($prev, $current) = ($current, shift @ready || $idle);
134 Coro::State::transfer($prev, $current);
135}
136
137=item yield 190=item cede
138 191
139Yield to other processes. This function puts the current process into the 192"Cede" to other processes. This function puts the current process into the
140ready 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.
141 195
142=cut 196=cut
143 197
144sub yield {
145 $current->ready;
146 &schedule;
147}
148
149=item terminate 198=item terminate [arg...]
150 199
151Terminates the current process. 200Terminates the current process with the given status values (see L<cancel>).
152 201
153=cut 202=cut
154 203
155sub terminate { 204sub terminate {
156 &schedule; 205 $current->cancel (@_);
157} 206}
158 207
159=back 208=back
160 209
161# dynamic methods 210# dynamic methods
164 213
165These are the methods you can call on process objects. 214These are the methods you can call on process objects.
166 215
167=over 4 216=over 4
168 217
169=item new Coro \&sub; 218=item new Coro \&sub [, @args...]
170 219
171Create 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
172automatically 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
173the ready queue by calling the ready method. 223by calling the ready method.
174 224
175=cut 225=cut
226
227sub _newcoro {
228 terminate &{+shift};
229}
176 230
177sub new { 231sub new {
178 my $class = shift; 232 my $class = shift;
179 my $proc = $_[0];
180 bless { 233 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 234 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 235 }, $class;
183} 236}
184 237
185=item $process->ready 238=item $process->ready
186 239
187Put the current process into the ready queue. 240Put the given process into the ready queue.
188 241
189=cut 242=cut
190 243
191sub ready { 244=item $process->cancel (arg...)
192 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;
193} 328}
194 329
195=back 330=back
196 331
197=cut 332=cut
198 333
1991; 3341;
200 335
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
201=head1 SEE ALSO 346=head1 SEE ALSO
202 347
203L<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>.
204L<Coro::Signal>, L<Coro::State>. 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>
205 355
206=head1 AUTHOR 356=head1 AUTHOR
207 357
208 Marc Lehmann <pcg@goof.com> 358 Marc Lehmann <schmorp@schmorp.de>
209 http://www.goof.com/pcg/marc/ 359 http://home.schmorp.de/
210 360
211=cut 361=cut
212 362

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