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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 1.40 by root, Sun Oct 28 17:00:05 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$VERSION = 0.51;
37 44
38@EXPORT = qw(async yield schedule terminate); 45@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($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 $manager;
122$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 while (@destroy) {
130 my $coro = pop @destroy;
131 $coro->{status} ||= [];
132 $_->ready for @{delete $coro->{join} || []};
133 $coro->{_coro_state} = $manager->{_coro_state};
134 }
135 &schedule;
136 }
137};
106 138
107# static methods. not really. 139# static methods. not really.
108 140
109=head2 STATIC METHODS 141=head2 STATIC METHODS
110 142
… …
128 160
129=cut 161=cut
130 162
131sub async(&@) { 163sub async(&@) {
132 my $pid = new Coro @_; 164 my $pid = new Coro @_;
165 $manager->ready; # this ensures that the stack is cloned from the manager
133 $pid->ready; 166 $pid->ready;
134 $pid; 167 $pid;
135} 168}
136 169
137=item schedule 170=item schedule
… …
140into the ready queue, so calling this function usually means you will 173into the ready queue, so calling this function usually means you will
141never be called again. 174never be called again.
142 175
143=cut 176=cut
144 177
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 178=item cede
154 179
155Yield to other processes. This function puts the current process into the 180"Cede" to other processes. This function puts the current process into the
156ready queue and calls C<schedule>. 181ready queue and calls C<schedule>, which has the effect of giving up the
182current "timeslice" to other coroutines of the same or higher priority.
157 183
158=cut 184=cut
159 185
160sub yield { 186=item terminate [arg...]
187
188Terminates the current process.
189
190Future versions of this function will allow result arguments.
191
192=cut
193
194sub terminate {
195 $current->{status} = [@_];
161 $current->ready; 196 $current->cancel;
162 &schedule; 197 &schedule;
163} 198 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} 199}
177 200
178=back 201=back
179 202
180# dynamic methods 203# dynamic methods
… …
186=over 4 209=over 4
187 210
188=item new Coro \&sub [, @args...] 211=item new Coro \&sub [, @args...]
189 212
190Create a new process and return it. When the sub returns the process 213Create a new process and return it. When the sub returns the process
191automatically terminates. To start the process you must first put it into 214automatically terminates as if C<terminate> with the returned values were
192the ready queue by calling the ready method. 215called. To start the process you must first put it into the ready queue by
216calling the ready method.
193 217
194The coderef you submit MUST NOT be a closure that refers to variables 218The coderef you submit MUST NOT be a closure that refers to variables
195in an outer scope. This does NOT work. Pass arguments into it instead. 219in an outer scope. This does NOT work. Pass arguments into it instead.
196 220
197=cut 221=cut
… …
207 }, $class; 231 }, $class;
208} 232}
209 233
210=item $process->ready 234=item $process->ready
211 235
212Put the current process into the ready queue. 236Put the given process into the ready queue.
213 237
214=cut 238=cut
215 239
216sub ready { 240=item $process->cancel
241
242Like C<terminate>, but terminates the specified process instead.
243
244=cut
245
246sub cancel {
217 push @ready, $_[0]; 247 push @destroy, $_[0];
248 $manager->ready;
249 &schedule if $current == $_[0];
250}
251
252=item $process->join
253
254Wait until the coroutine terminates and return any values given to the
255C<terminate> function. C<join> can be called multiple times from multiple
256processes.
257
258=cut
259
260sub join {
261 my $self = shift;
262 unless ($self->{status}) {
263 push @{$self->{join}}, $current;
264 &schedule;
265 }
266 wantarray ? @{$self->{status}} : $self->{status}[0];
267}
268
269=item $oldprio = $process->prio($newprio)
270
271Sets the priority of the process. Higher priority processes get run before
272lower priority processes. Priorities are smalled signed integer (currently
273-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
274tag :prio to get then):
275
276 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
277 3 > 1 > 0 > -1 > -3 > -4
278
279 # set priority to HIGH
280 current->prio(PRIO_HIGH);
281
282The idle coroutine ($Coro::idle) always has a lower priority than any
283existing coroutine.
284
285Changing the priority of the current process will take effect immediately,
286but changing the priority of processes in the ready queue (but not
287running) will only take effect after the next schedule (of that
288process). This is a bug that will be fixed in some future version.
289
290=cut
291
292sub prio {
293 my $old = $_[0]{prio};
294 $_[0]{prio} = $_[1] if @_ > 1;
295 $old;
296}
297
298=item $newprio = $process->nice($change)
299
300Similar to C<prio>, but subtract the given value from the priority (i.e.
301higher values mean lower priority, just as in unix).
302
303=cut
304
305sub nice {
306 $_[0]{prio} -= $_[1];
218} 307}
219 308
220=back 309=back
221 310
222=cut 311=cut
223 312
2241; 3131;
225 314
226=head1 BUGS 315=head1 BUGS/LIMITATIONS
227 316
228 - could be faster, especially when the core would introduce special 317 - you must make very sure that no coro is still active on global destruction.
229 support for coroutines (like it does for threads). 318 very bad things might happen otherwise (usually segfaults).
230 - there is still a memleak on coroutine termination that I could not 319 - this module is not thread-safe. You must only ever use this module from
231 identify. Could be as small as a single SV. 320 the same thread (this requirement might be loosened in the future to
232 - this module is not well-tested. 321 allow per-thread schedulers, but Coro::State does not yet allow this).
233 322
234=head1 SEE ALSO 323=head1 SEE ALSO
235 324
236L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 325L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
237L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 326L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
327L<Coro::Handle>, L<Coro::Socket>.
238 328
239=head1 AUTHOR 329=head1 AUTHOR
240 330
241 Marc Lehmann <pcg@goof.com> 331 Marc Lehmann <pcg@goof.com>
242 http://www.goof.com/pcg/marc/ 332 http://www.goof.com/pcg/marc/

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