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Comparing Coro/Coro.pm (file contents):
Revision 1.21 by root, Sun Jul 22 03:24:10 2001 UTC vs.
Revision 1.38 by root, Wed Oct 3 01:09:56 2001 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. 26This module is still experimental, see the BUGS section below.
27 27
28In this module, coroutines are defined as "callchain + lexical variables 28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W), that is, a coroutine has it's own callchain, it's 29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30own set of lexicals and it's own set of perl's most important global 30callchain, it's own set of lexicals and it's own set of perl's most
31variables. 31important global variables.
32
33WARNING: When using this module, make sure that, at program end, no
34coroutines are still running OR just call exit before falling off the
35end. The reason for this is that some coroutine of yours might have called
36into a C function, and falling off the end of main:: results in returning
37to that C function instead if to the main C interpreter.
38 32
39=cut 33=cut
40 34
41package Coro; 35package Coro;
42 36
37no warnings qw(uninitialized);
38
43use Coro::State; 39use Coro::State;
44 40
45use base Exporter; 41use base Exporter;
46 42
47$VERSION = 0.10; 43$VERSION = 0.51;
48 44
49@EXPORT = qw(async yield schedule terminate current); 45@EXPORT = qw(async cede schedule terminate current);
50@EXPORT_OK = qw($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}};
51 50
52{ 51{
53 my @async; 52 my @async;
53 my $init;
54 54
55 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
56 sub import { 56 sub import {
57 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
60 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
61 my @attrs; 61 my @attrs;
62 for (@_) { 62 for (@_) {
63 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
64 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 }
65 } else { 72 } else {
66 push @attrs, $_; 73 push @attrs, $_;
67 } 74 }
68 } 75 }
69 return $old ? $old->($package, $ref, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
70 }; 77 };
71 } 78 }
72 79
73 sub INIT {
74 &async(pop @async) while @async;
75 }
76} 80}
77 81
78=item $main 82=item $main
79 83
80This coroutine represents the main program. 84This coroutine represents the main program.
… …
109our $idle = new Coro sub { 113our $idle = new Coro sub {
110 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
111 exit(51); 115 exit(51);
112}; 116};
113 117
114# we really need priorities... 118# this coroutine is necessary because a coroutine
115my @ready; # the ready queue. hehe, rather broken ;) 119# cannot destroy itself.
120my @destroy;
121my $manager;
122$manager = new Coro sub {
123 while() {
124 # by overwriting the state object with the manager we destroy it
125 # while still being able to schedule this coroutine (in case it has
126 # been readied multiple times. this is harmless since the manager
127 # can be called as many times as neccessary and will always
128 # remove itself from the runqueue
129 (pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy;
130 &schedule;
131 }
132};
116 133
117# static methods. not really. 134# static methods. not really.
118 135
119=head2 STATIC METHODS 136=head2 STATIC METHODS
120 137
… …
138 155
139=cut 156=cut
140 157
141sub async(&@) { 158sub async(&@) {
142 my $pid = new Coro @_; 159 my $pid = new Coro @_;
160 $manager->ready; # this ensures that the stack is cloned from the manager
143 $pid->ready; 161 $pid->ready;
144 $pid; 162 $pid;
145} 163}
146 164
147=item schedule 165=item schedule
… …
150into the ready queue, so calling this function usually means you will 168into the ready queue, so calling this function usually means you will
151never be called again. 169never be called again.
152 170
153=cut 171=cut
154 172
155my $prev;
156
157sub schedule {
158 # should be done using priorities :(
159 ($prev, $current) = ($current, shift @ready || $idle);
160 Coro::State::transfer($prev, $current);
161}
162
163=item yield 173=item cede
164 174
165Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
166ready queue and calls C<schedule>. 176ready queue and calls C<schedule>, which has the effect of giving up the
177current "timeslice" to other coroutines of the same or higher priority.
167 178
168=cut 179=cut
169 180
170sub yield { 181=item terminate
182
183Terminates the current process.
184
185Future versions of this function will allow result arguments.
186
187=cut
188
189sub terminate {
171 $current->ready; 190 $current->cancel;
172 &schedule; 191 &schedule;
173} 192 die; # NORETURN
174
175=item terminate
176
177Terminates the current process.
178
179Future versions of this function will allow result arguments.
180
181=cut
182
183sub terminate {
184 $current->{_results} = [@_];
185 delete $current->{_coro_state};
186 &schedule;
187} 193}
188 194
189=back 195=back
190 196
191# dynamic methods 197# dynamic methods
… …
222 228
223Put the current process into the ready queue. 229Put the current process into the ready queue.
224 230
225=cut 231=cut
226 232
227sub ready { 233=item $process->cancel
234
235Like C<terminate>, but terminates the specified process instead.
236
237=cut
238
239sub cancel {
228 push @ready, $_[0]; 240 push @destroy, $_[0];
241 $manager->ready;
242 &schedule if $current == $_[0];
243}
244
245=item $oldprio = $process->prio($newprio)
246
247Sets the priority of the process. Higher priority processes get run before
248lower priority processes. Priorities are smalled signed integer (currently
249-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
250tag :prio to get then):
251
252 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
253 3 > 1 > 0 > -1 > -3 > -4
254
255 # set priority to HIGH
256 current->prio(PRIO_HIGH);
257
258The idle coroutine ($Coro::idle) always has a lower priority than any
259existing coroutine.
260
261Changing the priority of the current process will take effect immediately,
262but changing the priority of processes in the ready queue (but not
263running) will only take effect after the next schedule (of that
264process). This is a bug that will be fixed in some future version.
265
266=cut
267
268sub prio {
269 my $old = $_[0]{prio};
270 $_[0]{prio} = $_[1] if @_ > 1;
271 $old;
272}
273
274=item $newprio = $process->nice($change)
275
276Similar to C<prio>, but subtract the given value from the priority (i.e.
277higher values mean lower priority, just as in unix).
278
279=cut
280
281sub nice {
282 $_[0]{prio} -= $_[1];
229} 283}
230 284
231=back 285=back
232 286
233=cut 287=cut
234 288
2351; 2891;
236 290
237=head1 BUGS/LIMITATIONS 291=head1 BUGS/LIMITATIONS
238 292
239 - could be faster, especially when the core would introduce special 293 - you must make very sure that no coro is still active on global destruction.
240 support for coroutines (like it does for threads). 294 very bad things might happen otherwise (usually segfaults).
241 - there is still a memleak on coroutine termination that I could not
242 identify. Could be as small as a single SV.
243 - this module is not well-tested.
244 - if variables or arguments "disappear" (become undef) or become
245 corrupted please contact the author so he cen iron out the
246 remaining bugs.
247 - this module is not thread-safe. You must only ever use this module from 295 - this module is not thread-safe. You must only ever use this module from
248 the same thread (this requirement might be loosened in the future to 296 the same thread (this requirement might be loosened in the future to
249 allow per-thread schedulers, but Coro::State does not yet allow this). 297 allow per-thread schedulers, but Coro::State does not yet allow this).
250 298
251=head1 SEE ALSO 299=head1 SEE ALSO
252 300
253L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 301L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
254L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 302L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
303L<Coro::Handle>, L<Coro::Socket>.
255 304
256=head1 AUTHOR 305=head1 AUTHOR
257 306
258 Marc Lehmann <pcg@goof.com> 307 Marc Lehmann <pcg@goof.com>
259 http://www.goof.com/pcg/marc/ 308 http://www.goof.com/pcg/marc/

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