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Comparing Coro/Coro.pm (file contents):
Revision 1.14 by root, Tue Jul 17 02:21:56 2001 UTC vs.
Revision 1.36 by root, Mon Sep 24 01:36:20 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
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
28=cut 33=cut
29 34
30package Coro; 35package Coro;
31 36
37no warnings qw(uninitialized);
38
32use Coro::State; 39use Coro::State;
33 40
34use base Exporter; 41use base Exporter;
35 42
36$VERSION = 0.05; 43$VERSION = 0.5;
37 44
38@EXPORT = qw(async yield schedule terminate); 45@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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}};
40 50
41{ 51{
42 use subs 'async';
43
44 my @async; 52 my @async;
53 my $init;
45 54
46 # this way of handling attributes simply is NOT scalable ;() 55 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 56 sub import {
48 Coro->export_to_level(1, @_); 57 Coro->export_to_level(1, @_);
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 58 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
51 my ($package, $ref) = (shift, shift); 60 my ($package, $ref) = (shift, shift);
52 my @attrs; 61 my @attrs;
53 for (@_) { 62 for (@_) {
54 if ($_ eq "Coro") { 63 if ($_ eq "Coro") {
55 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 }
56 } else { 72 } else {
57 push @attrs, @_; 73 push @attrs, $_;
58 } 74 }
59 } 75 }
60 return $old ? $old->($package, $name, @attrs) : @attrs; 76 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 77 };
62 } 78 }
63 79
64 sub INIT {
65 async pop @async while @async;
66 }
67} 80}
68 81
69=item $main 82=item $main
70 83
71This coroutine represents the main program. 84This coroutine represents the main program.
72 85
73=cut 86=cut
74 87
75our $main = new Coro; 88our $main = new Coro;
76 89
77=item $current 90=item $current (or as function: current)
78 91
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 92The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 93
81=cut 94=cut
82 95
… …
84if ($current) { 97if ($current) {
85 $main->{specific} = $current->{specific}; 98 $main->{specific} = $current->{specific};
86} 99}
87 100
88our $current = $main; 101our $current = $main;
102
103sub current() { $current }
89 104
90=item $idle 105=item $idle
91 106
92The coroutine to switch to when no other coroutine is running. The default 107The coroutine to switch to when no other coroutine is running. The default
93implementation prints "FATAL: deadlock detected" and exits. 108implementation prints "FATAL: deadlock detected" and exits.
… …
98our $idle = new Coro sub { 113our $idle = new Coro sub {
99 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
100 exit(51); 115 exit(51);
101}; 116};
102 117
103# we really need priorities... 118# this coroutine is necessary because a coroutine
104## my @ready; #d# 119# cannot destroy itself.
105our @ready = (); # the ready queue. hehe, rather broken ;) 120my @destroy;
121my $manager = new Coro sub {
122 while() {
123 delete ((pop @destroy)->{_coro_state}) while @destroy;
124 &schedule;
125 }
126};
106 127
107# static methods. not really. 128# static methods. not really.
108 129
109=head2 STATIC METHODS 130=head2 STATIC METHODS
110 131
… …
128 149
129=cut 150=cut
130 151
131sub async(&@) { 152sub async(&@) {
132 my $pid = new Coro @_; 153 my $pid = new Coro @_;
154 $manager->ready; # this ensures that the stack is cloned from the manager
133 $pid->ready; 155 $pid->ready;
134 $pid; 156 $pid;
135} 157}
136 158
137=item schedule 159=item schedule
… …
140into the ready queue, so calling this function usually means you will 162into the ready queue, so calling this function usually means you will
141never be called again. 163never be called again.
142 164
143=cut 165=cut
144 166
145my $prev;
146
147sub schedule {
148 # should be done using priorities :(
149 ($prev, $current) = ($current, shift @ready || $idle);
150 Coro::State::transfer($prev, $current);
151}
152
153=item yield 167=item cede
154 168
155Yield to other processes. This function puts the current process into the 169"Cede" to other processes. This function puts the current process into the
156ready queue and calls C<schedule>. 170ready queue and calls C<schedule>, which has the effect of giving up the
171current "timeslice" to other coroutines of the same or higher priority.
157 172
158=cut 173=cut
159 174
160sub yield { 175=item terminate
176
177Terminates the current process.
178
179Future versions of this function will allow result arguments.
180
181=cut
182
183sub terminate {
161 $current->ready; 184 $current->cancel;
162 &schedule; 185 &schedule;
163} 186 die; # NORETURN
164
165=item terminate
166
167Terminates the current process.
168
169Future versions of this function will allow result arguments.
170
171=cut
172
173sub terminate {
174 $current->{_results} = [@_];
175 &schedule;
176} 187}
177 188
178=back 189=back
179 190
180# dynamic methods 191# dynamic methods
… …
211 222
212Put the current process into the ready queue. 223Put the current process into the ready queue.
213 224
214=cut 225=cut
215 226
216sub ready { 227=item $process->cancel
228
229Like C<terminate>, but terminates the specified process instead.
230
231=cut
232
233sub cancel {
217 push @ready, $_[0]; 234 push @destroy, $_[0];
235 $manager->ready;
236 &schedule if $current == $_[0];
237}
238
239=item $oldprio = $process->prio($newprio)
240
241Sets the priority of the process. Higher priority processes get run before
242lower priority processes. Priorities are smalled signed integer (currently
243-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
244tag :prio to get then):
245
246 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
247 3 > 1 > 0 > -1 > -3 > -4
248
249 # set priority to HIGH
250 current->prio(PRIO_HIGH);
251
252The idle coroutine ($Coro::idle) always has a lower priority than any
253existing coroutine.
254
255Changing the priority of the current process will take effect immediately,
256but changing the priority of processes in the ready queue (but not
257running) will only take effect after the next schedule (of that
258process). This is a bug that will be fixed in some future version.
259
260=cut
261
262sub prio {
263 my $old = $_[0]{prio};
264 $_[0]{prio} = $_[1] if @_ > 1;
265 $old;
266}
267
268=item $newprio = $process->nice($change)
269
270Similar to C<prio>, but subtract the given value from the priority (i.e.
271higher values mean lower priority, just as in unix).
272
273=cut
274
275sub nice {
276 $_[0]{prio} -= $_[1];
218} 277}
219 278
220=back 279=back
221 280
222=cut 281=cut
223 282
2241; 2831;
225 284
226=head1 BUGS 285=head1 BUGS/LIMITATIONS
227 286
228 - could be faster, especially when the core would introduce special 287 - you must make very sure that no coro is still active on global destruction.
229 support for coroutines (like it does for threads). 288 very bad things might happen otherwise (usually segfaults).
230 - there is still a memleak on coroutine termination that I could not 289 - this module is not thread-safe. You must only ever use this module from
231 identify. Could be as small as a single SV. 290 the same thread (this requirement might be loosened in the future to
232 - this module is not well-tested. 291 allow per-thread schedulers, but Coro::State does not yet allow this).
233 292
234=head1 SEE ALSO 293=head1 SEE ALSO
235 294
236L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 295L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
237L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 296L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
297L<Coro::Handle>, L<Coro::Socket>.
238 298
239=head1 AUTHOR 299=head1 AUTHOR
240 300
241 Marc Lehmann <pcg@goof.com> 301 Marc Lehmann <pcg@goof.com>
242 http://www.goof.com/pcg/marc/ 302 http://www.goof.com/pcg/marc/

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