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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 1.56 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
24threads but don't run in parallel.
25
26In this module, coroutines are defined as "callchain + lexical variables
27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
30
23=cut 31=cut
24 32
25package Coro; 33package Coro;
26 34
35BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
36
27use Coro::State; 37use Coro::State;
28 38
39use vars qw($idle $main $current);
40
29use base Exporter; 41use base Exporter;
30 42
31$VERSION = 0.04; 43$VERSION = "0.9";
32 44
33@EXPORT = qw(async yield schedule); 45@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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}};
35 50
36{ 51{
37 use subs 'async';
38
39 my @async; 52 my @async;
53 my $init;
40 54
41 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 56 sub import {
43 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
47 my @attrs; 61 my @attrs;
48 for (@_) { 62 for (@_) {
49 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
50 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 }
51 } else { 72 } else {
52 push @attrs, @_; 73 push @attrs, $_;
53 } 74 }
54 } 75 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 77 };
57 } 78 }
58 79
59 sub INIT {
60 async pop @async while @async;
61 }
62} 80}
81
82=over 4
63 83
64=item $main 84=item $main
65 85
66This coroutine represents the main program. 86This coroutine represents the main program.
67 87
68=cut 88=cut
69 89
70our $main = new Coro; 90$main = new Coro;
71 91
72=item $current 92=item $current (or as function: current)
73 93
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 94The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 95
76=cut 96=cut
77 97
78# maybe some other module used Coro::Specific before... 98# maybe some other module used Coro::Specific before...
79if ($current) { 99if ($current) {
80 $main->{specific} = $current->{specific}; 100 $main->{specific} = $current->{specific};
81} 101}
82 102
83our $current = $main; 103$current = $main;
104
105sub current() { $current }
84 106
85=item $idle 107=item $idle
86 108
87The coroutine to switch to when no other coroutine is running. The default 109The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 110implementation prints "FATAL: deadlock detected" and exits.
89 111
90=cut 112=cut
91 113
92# should be done using priorities :( 114# should be done using priorities :(
93our $idle = new Coro sub { 115$idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 116 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 117 exit(51);
96}; 118};
97 119
98# we really need priorities... 120# this coroutine is necessary because a coroutine
99my @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};
100 140
101# static methods. not really. 141# static methods. not really.
102 142
143=back
144
103=head2 STATIC METHODS 145=head2 STATIC METHODS
104 146
105Static methods are actually functions that operate on the current process only. 147Static methods are actually functions that operate on the current process only.
106 148
107=over 4 149=over 4
108 150
109=item async { ... }; 151=item async { ... } [@args...]
110 152
111Create a new asynchronous process and return it's process object 153Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 154(usually unused). When the sub returns the new process is automatically
113terminated. 155terminated.
114 156
115=cut 157 # create a new coroutine that just prints its arguments
158 async {
159 print "@_\n";
160 } 1,2,3,4;
116 161
162The coderef you submit MUST NOT be a closure that refers to variables
163in an outer scope. This does NOT work. Pass arguments into it instead.
164
165=cut
166
117sub async(&) { 167sub async(&@) {
118 (new Coro $_[0])->ready; 168 my $pid = new Coro @_;
169 $manager->ready; # this ensures that the stack is cloned from the manager
170 $pid->ready;
171 $pid;
119} 172}
120 173
121=item schedule 174=item schedule
122 175
123Calls the scheduler. Please note that the current process will not be put 176Calls the scheduler. Please note that the current process will not be put
124into the ready queue, so calling this function usually means you will 177into the ready queue, so calling this function usually means you will
125never be called again. 178never be called again.
126 179
127=cut 180=cut
128 181
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 182=item cede
138 183
139Yield to other processes. This function puts the current process into the 184"Cede" to other processes. This function puts the current process into the
140ready 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.
141 187
142=cut 188=cut
143 189
144sub 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} = [@_];
145 $current->ready; 200 $current->cancel;
146 &schedule; 201 &schedule;
147} 202 die; # NORETURN
148
149=item terminate
150
151Terminates the current process.
152
153=cut
154
155sub terminate {
156 &schedule;
157} 203}
158 204
159=back 205=back
160 206
161# dynamic methods 207# dynamic methods
… …
164 210
165These are the methods you can call on process objects. 211These are the methods you can call on process objects.
166 212
167=over 4 213=over 4
168 214
169=item new Coro \&sub; 215=item new Coro \&sub [, @args...]
170 216
171Create 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
172automatically 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
173the ready queue by calling the ready method. 220by calling the ready method.
174 221
175=cut 222=cut
223
224sub _newcoro {
225 terminate &{+shift};
226}
176 227
177sub new { 228sub new {
178 my $class = shift; 229 my $class = shift;
179 my $proc = $_[0];
180 bless { 230 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 231 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 232 }, $class;
183} 233}
184 234
185=item $process->ready 235=item $process->ready
186 236
187Put the current process into the ready queue. 237Put the given process into the ready queue.
188 238
189=cut 239=cut
190 240
191sub ready { 241=item $process->cancel
242
243Like C<terminate>, but terminates the specified process instead.
244
245=cut
246
247sub cancel {
192 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;
193} 322}
194 323
195=back 324=back
196 325
197=cut 326=cut
198 327
1991; 3281;
200 329
330=head1 BUGS/LIMITATIONS
331
332 - you must make very sure that no coro is still active on global
333 destruction. very bad things might happen otherwise (usually segfaults).
334
335 - this module is not thread-safe. You should only ever use this module
336 from the same thread (this requirement might be losened in the future
337 to allow per-thread schedulers, but Coro::State does not yet allow
338 this).
339
201=head1 SEE ALSO 340=head1 SEE ALSO
202 341
203L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 342L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
204L<Coro::Signal>, L<Coro::State>. 343L<Coro::Signal>, L<Coro::State>, L<Coro::Timer>, L<Coro::Event>,
344L<Coro::L<Coro::RWLock>, Handle>, L<Coro::Socket>.
205 345
206=head1 AUTHOR 346=head1 AUTHOR
207 347
208 Marc Lehmann <pcg@goof.com> 348 Marc Lehmann <pcg@goof.com>
209 http://www.goof.com/pcg/marc/ 349 http://www.goof.com/pcg/marc/

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