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Comparing Coro/Coro.pm (file contents):
Revision 1.11 by root, Sun Jul 15 03:24:18 2001 UTC vs.
Revision 1.37 by root, Mon Sep 24 02:25:44 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
37no warnings qw(uninitialized);
38
27use Coro::State; 39use Coro::State;
28 40
29use base Exporter; 41use base Exporter;
30 42
31$VERSION = 0.04; 43$VERSION = 0.5;
32 44
33@EXPORT = qw(async yield schedule); 45@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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}
63 81
64=item $main 82=item $main
65 83
66This coroutine represents the main program. 84This coroutine represents the main program.
67 85
68=cut 86=cut
69 87
70our $main = new Coro; 88our $main = new Coro;
71 89
72=item $current 90=item $current (or as function: current)
73 91
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 92The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 93
76=cut 94=cut
77 95
… …
79if ($current) { 97if ($current) {
80 $main->{specific} = $current->{specific}; 98 $main->{specific} = $current->{specific};
81} 99}
82 100
83our $current = $main; 101our $current = $main;
102
103sub current() { $current }
84 104
85=item $idle 105=item $idle
86 106
87The 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
88implementation prints "FATAL: deadlock detected" and exits. 108implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 113our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 114 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 115 exit(51);
96}; 116};
97 117
98# we really need priorities... 118# this coroutine is necessary because a coroutine
99my @ready = (); # the ready queue. hehe, rather broken ;) 119# cannot destroy itself.
120my @destroy;
121my $manager = new Coro sub {
122 while() {
123 # by overwriting the state object with the manager we destroy it
124 # while still being able to schedule this coroutine (in case it has
125 # been readied multiple times. this is harmless since the manager
126 # can be called as many times as neccessary and will always
127 # remove itself from the runqueue
128 (pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy;
129 &schedule;
130 }
131};
100 132
101# static methods. not really. 133# static methods. not really.
102 134
103=head2 STATIC METHODS 135=head2 STATIC METHODS
104 136
105Static methods are actually functions that operate on the current process only. 137Static methods are actually functions that operate on the current process only.
106 138
107=over 4 139=over 4
108 140
109=item async { ... }; 141=item async { ... } [@args...]
110 142
111Create a new asynchronous process and return it's process object 143Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 144(usually unused). When the sub returns the new process is automatically
113terminated. 145terminated.
114 146
115=cut 147 # create a new coroutine that just prints its arguments
148 async {
149 print "@_\n";
150 } 1,2,3,4;
116 151
152The coderef you submit MUST NOT be a closure that refers to variables
153in an outer scope. This does NOT work. Pass arguments into it instead.
154
155=cut
156
117sub async(&) { 157sub async(&@) {
118 my $pid = new Coro $_[0]; 158 my $pid = new Coro @_;
159 $manager->ready; # this ensures that the stack is cloned from the manager
119 $pid->ready; 160 $pid->ready;
120 $pid; 161 $pid;
121} 162}
122 163
123=item schedule 164=item schedule
… …
126into the ready queue, so calling this function usually means you will 167into the ready queue, so calling this function usually means you will
127never be called again. 168never be called again.
128 169
129=cut 170=cut
130 171
131my $prev;
132
133sub schedule {
134 # should be done using priorities :(
135 ($prev, $current) = ($current, shift @ready || $idle);
136 Coro::State::transfer($prev, $current);
137}
138
139=item yield 172=item cede
140 173
141Yield to other processes. This function puts the current process into the 174"Cede" to other processes. This function puts the current process into the
142ready queue and calls C<schedule>. 175ready queue and calls C<schedule>, which has the effect of giving up the
176current "timeslice" to other coroutines of the same or higher priority.
143 177
144=cut 178=cut
145 179
146sub yield { 180=item terminate
181
182Terminates the current process.
183
184Future versions of this function will allow result arguments.
185
186=cut
187
188sub terminate {
147 $current->ready; 189 $current->cancel;
148 &schedule; 190 &schedule;
149} 191 die; # NORETURN
150
151=item terminate
152
153Terminates the current process.
154
155=cut
156
157sub terminate {
158 &schedule;
159} 192}
160 193
161=back 194=back
162 195
163# dynamic methods 196# dynamic methods
… …
166 199
167These are the methods you can call on process objects. 200These are the methods you can call on process objects.
168 201
169=over 4 202=over 4
170 203
171=item new Coro \&sub; 204=item new Coro \&sub [, @args...]
172 205
173Create a new process and return it. When the sub returns the process 206Create a new process and return it. When the sub returns the process
174automatically terminates. To start the process you must first put it into 207automatically terminates. To start the process you must first put it into
175the ready queue by calling the ready method. 208the ready queue by calling the ready method.
176 209
210The coderef you submit MUST NOT be a closure that refers to variables
211in an outer scope. This does NOT work. Pass arguments into it instead.
212
177=cut 213=cut
214
215sub _newcoro {
216 terminate &{+shift};
217}
178 218
179sub new { 219sub new {
180 my $class = shift; 220 my $class = shift;
181 my $proc = $_[0];
182 bless { 221 bless {
183 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 222 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
184 }, $class; 223 }, $class;
185} 224}
186 225
187=item $process->ready 226=item $process->ready
188 227
189Put the current process into the ready queue. 228Put the current process into the ready queue.
190 229
191=cut 230=cut
192 231
193sub ready { 232=item $process->cancel
233
234Like C<terminate>, but terminates the specified process instead.
235
236=cut
237
238sub cancel {
194 push @ready, $_[0]; 239 push @destroy, $_[0];
240 $manager->ready;
241 &schedule if $current == $_[0];
242}
243
244=item $oldprio = $process->prio($newprio)
245
246Sets the priority of the process. Higher priority processes get run before
247lower priority processes. Priorities are smalled signed integer (currently
248-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
249tag :prio to get then):
250
251 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
252 3 > 1 > 0 > -1 > -3 > -4
253
254 # set priority to HIGH
255 current->prio(PRIO_HIGH);
256
257The idle coroutine ($Coro::idle) always has a lower priority than any
258existing coroutine.
259
260Changing the priority of the current process will take effect immediately,
261but changing the priority of processes in the ready queue (but not
262running) will only take effect after the next schedule (of that
263process). This is a bug that will be fixed in some future version.
264
265=cut
266
267sub prio {
268 my $old = $_[0]{prio};
269 $_[0]{prio} = $_[1] if @_ > 1;
270 $old;
271}
272
273=item $newprio = $process->nice($change)
274
275Similar to C<prio>, but subtract the given value from the priority (i.e.
276higher values mean lower priority, just as in unix).
277
278=cut
279
280sub nice {
281 $_[0]{prio} -= $_[1];
195} 282}
196 283
197=back 284=back
198 285
199=cut 286=cut
200 287
2011; 2881;
202 289
290=head1 BUGS/LIMITATIONS
291
292 - you must make very sure that no coro is still active on global destruction.
293 very bad things might happen otherwise (usually segfaults).
294 - this module is not thread-safe. You must only ever use this module from
295 the same thread (this requirement might be loosened in the future to
296 allow per-thread schedulers, but Coro::State does not yet allow this).
297
203=head1 SEE ALSO 298=head1 SEE ALSO
204 299
205L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 300L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
206L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 301L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
302L<Coro::Handle>, L<Coro::Socket>.
207 303
208=head1 AUTHOR 304=head1 AUTHOR
209 305
210 Marc Lehmann <pcg@goof.com> 306 Marc Lehmann <pcg@goof.com>
211 http://www.goof.com/pcg/marc/ 307 http://www.goof.com/pcg/marc/

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