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Comparing cvsroot/Coro/Coro.pm (file contents):
Revision 1.13 by root, Tue Jul 17 00:24:14 2001 UTC vs.
Revision 1.32 by root, Sun Sep 2 01:03:53 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
24Threads but don't run in parallel.
25
26This module is still experimental, see the BUGS section below.
27
28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
27use Coro::State; 37use Coro::State;
28 38
29use base Exporter; 39use base Exporter;
30 40
31$VERSION = 0.05; 41$VERSION = 0.49;
32 42
33@EXPORT = qw(async yield schedule terminate); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 44%EXPORT_TAGS = (
45 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
46);
47@EXPORT_OK = @{$EXPORT_TAGS{prio}};
35 48
36{ 49{
37 use subs 'async';
38
39 my @async; 50 my @async;
51 my $init;
40 52
41 # this way of handling attributes simply is NOT scalable ;() 53 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 54 sub import {
43 Coro->export_to_level(1, @_); 55 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 56 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 58 my ($package, $ref) = (shift, shift);
47 my @attrs; 59 my @attrs;
48 for (@_) { 60 for (@_) {
49 if ($_ eq "Coro") { 61 if ($_ eq "Coro") {
50 push @async, $ref; 62 push @async, $ref;
63 unless ($init++) {
64 eval q{
65 sub INIT {
66 &async(pop @async) while @async;
67 }
68 };
69 }
51 } else { 70 } else {
52 push @attrs, @_; 71 push @attrs, $_;
53 } 72 }
54 } 73 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 74 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 75 };
57 } 76 }
58 77
59 sub INIT {
60 async pop @async while @async;
61 }
62} 78}
63 79
64=item $main 80=item $main
65 81
66This coroutine represents the main program. 82This coroutine represents the main program.
67 83
68=cut 84=cut
69 85
70our $main = new Coro; 86our $main = new Coro;
71 87
72=item $current 88=item $current (or as function: current)
73 89
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 90The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 91
76=cut 92=cut
77 93
… …
79if ($current) { 95if ($current) {
80 $main->{specific} = $current->{specific}; 96 $main->{specific} = $current->{specific};
81} 97}
82 98
83our $current = $main; 99our $current = $main;
100
101sub current() { $current }
84 102
85=item $idle 103=item $idle
86 104
87The coroutine to switch to when no other coroutine is running. The default 105The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 106implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 111our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 112 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 113 exit(51);
96}; 114};
97 115
98# we really need priorities... 116# this coroutine is necessary because a coroutine
99## my @ready; #d# 117# cannot destroy itself.
100our @ready = (); # the ready queue. hehe, rather broken ;) 118my @destroy;
119my $manager = new Coro sub {
120 while() {
121 delete ((pop @destroy)->{_coro_state}) while @destroy;
122 &schedule;
123 }
124};
101 125
102# static methods. not really. 126# static methods. not really.
103 127
104=head2 STATIC METHODS 128=head2 STATIC METHODS
105 129
… …
123 147
124=cut 148=cut
125 149
126sub async(&@) { 150sub async(&@) {
127 my $pid = new Coro @_; 151 my $pid = new Coro @_;
152 $manager->ready; # this ensures that the stack is cloned from the manager
128 $pid->ready; 153 $pid->ready;
129 $pid; 154 $pid;
130} 155}
131 156
132=item schedule 157=item schedule
… …
135into the ready queue, so calling this function usually means you will 160into the ready queue, so calling this function usually means you will
136never be called again. 161never be called again.
137 162
138=cut 163=cut
139 164
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 165=item cede
149 166
150Yield to other processes. This function puts the current process into the 167"Cede" to other processes. This function puts the current process into the
151ready queue and calls C<schedule>. 168ready queue and calls C<schedule>, which has the effect of giving up the
169current "timeslice" to other coroutines of the same or higher priority.
152 170
153=cut 171=cut
154 172
155sub yield { 173=item terminate
174
175Terminates the current process.
176
177Future versions of this function will allow result arguments.
178
179=cut
180
181sub terminate {
156 $current->ready; 182 $current->cancel;
157 &schedule; 183 &schedule;
158} 184 die; # NORETURN
159
160=item terminate
161
162Terminates the current process.
163
164Future versions of this function will allow result arguments.
165
166=cut
167
168sub terminate {
169 $current->{_results} = [@_];
170 &schedule;
171} 185}
172 186
173=back 187=back
174 188
175# dynamic methods 189# dynamic methods
… …
206 220
207Put the current process into the ready queue. 221Put the current process into the ready queue.
208 222
209=cut 223=cut
210 224
211sub ready { 225=item $process->cancel
226
227Like C<terminate>, but terminates the specified process instead.
228
229=cut
230
231sub cancel {
212 push @ready, $_[0]; 232 push @destroy, $_[0];
233 $manager->ready;
234}
235
236=item $oldprio = $process->prio($newprio)
237
238Sets the priority of the process. Higher priority processes get run before
239lower priority processes. Priorities are smalled signed integer (currently
240-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
241tag :prio to get then):
242
243 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
244 3 > 1 > 0 > -1 > -3 > -4
245
246 # set priority to HIGH
247 current->prio(PRIO_HIGH);
248
249The idle coroutine ($Coro::idle) always has a lower priority than any
250existing coroutine.
251
252Changing the priority of the current process will take effect immediately,
253but changing the priority of processes in the ready queue (but not
254running) will only take effect after the next schedule (of that
255process). This is a bug that will be fixed in some future version.
256
257=cut
258
259sub prio {
260 my $old = $_[0]{prio};
261 $_[0]{prio} = $_[1] if @_ > 1;
262 $old;
263}
264
265=item $newprio = $process->nice($change)
266
267Similar to C<prio>, but subtract the given value from the priority (i.e.
268higher values mean lower priority, just as in unix).
269
270=cut
271
272sub nice {
273 $_[0]{prio} -= $_[1];
213} 274}
214 275
215=back 276=back
216 277
217=cut 278=cut
218 279
2191; 2801;
220 281
282=head1 BUGS/LIMITATIONS
283
284 - could be faster, especially when the core would introduce special
285 support for coroutines (like it does for threads).
286 - there is still a memleak on coroutine termination that I could not
287 identify. Could be as small as a single SV.
288 - this module is not well-tested.
289 - if variables or arguments "disappear" (become undef) or become
290 corrupted please contact the author so he cen iron out the
291 remaining bugs.
292 - this module is not thread-safe. You must only ever use this module from
293 the same thread (this requirement might be loosened in the future to
294 allow per-thread schedulers, but Coro::State does not yet allow this).
295
221=head1 SEE ALSO 296=head1 SEE ALSO
222 297
223L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 298L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
224L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 299L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
300L<Coro::Handle>, L<Coro::Socket>.
225 301
226=head1 AUTHOR 302=head1 AUTHOR
227 303
228 Marc Lehmann <pcg@goof.com> 304 Marc Lehmann <pcg@goof.com>
229 http://www.goof.com/pcg/marc/ 305 http://www.goof.com/pcg/marc/

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