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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 1.39 by root, Tue Oct 9 00:39:08 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$VERSION = 0.51;
32 44
33@EXPORT = qw(async yield schedule); 45@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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 $manager;
122$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};
100 133
101# static methods. not really. 134# static methods. not really.
102 135
103=head2 STATIC METHODS 136=head2 STATIC METHODS
104 137
105Static methods are actually functions that operate on the current process only. 138Static methods are actually functions that operate on the current process only.
106 139
107=over 4 140=over 4
108 141
109=item async { ... }; 142=item async { ... } [@args...]
110 143
111Create a new asynchronous process and return it's process object 144Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 145(usually unused). When the sub returns the new process is automatically
113terminated. 146terminated.
114 147
115=cut 148 # create a new coroutine that just prints its arguments
149 async {
150 print "@_\n";
151 } 1,2,3,4;
116 152
153The coderef you submit MUST NOT be a closure that refers to variables
154in an outer scope. This does NOT work. Pass arguments into it instead.
155
156=cut
157
117sub async(&) { 158sub async(&@) {
118 my $pid = new Coro $_[0]; 159 my $pid = new Coro @_;
160 $manager->ready; # this ensures that the stack is cloned from the manager
119 $pid->ready; 161 $pid->ready;
120 $pid; 162 $pid;
121} 163}
122 164
123=item schedule 165=item schedule
… …
126into the ready queue, so calling this function usually means you will 168into the ready queue, so calling this function usually means you will
127never be called again. 169never be called again.
128 170
129=cut 171=cut
130 172
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 173=item cede
140 174
141Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
142ready 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.
143 178
144=cut 179=cut
145 180
146sub 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 {
147 $current->ready; 190 $current->cancel;
148 &schedule; 191 &schedule;
149} 192 die; # NORETURN
150
151=item terminate
152
153Terminates the current process.
154
155=cut
156
157sub terminate {
158 &schedule;
159} 193}
160 194
161=back 195=back
162 196
163# dynamic methods 197# dynamic methods
… …
166 200
167These are the methods you can call on process objects. 201These are the methods you can call on process objects.
168 202
169=over 4 203=over 4
170 204
171=item new Coro \&sub; 205=item new Coro \&sub [, @args...]
172 206
173Create a new process and return it. When the sub returns the process 207Create a new process and return it. When the sub returns the process
174automatically terminates. To start the process you must first put it into 208automatically terminates. To start the process you must first put it into
175the ready queue by calling the ready method. 209the ready queue by calling the ready method.
176 210
211The coderef you submit MUST NOT be a closure that refers to variables
212in an outer scope. This does NOT work. Pass arguments into it instead.
213
177=cut 214=cut
215
216sub _newcoro {
217 terminate &{+shift};
218}
178 219
179sub new { 220sub new {
180 my $class = shift; 221 my $class = shift;
181 my $proc = $_[0];
182 bless { 222 bless {
183 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 223 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
184 }, $class; 224 }, $class;
185} 225}
186 226
187=item $process->ready 227=item $process->ready
188 228
189Put the current process into the ready queue. 229Put the given process into the ready queue.
190 230
191=cut 231=cut
192 232
193sub ready { 233=item $process->cancel
234
235Like C<terminate>, but terminates the specified process instead.
236
237=cut
238
239sub cancel {
194 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];
195} 283}
196 284
197=back 285=back
198 286
199=cut 287=cut
200 288
2011; 2891;
202 290
291=head1 BUGS/LIMITATIONS
292
293 - you must make very sure that no coro is still active on global destruction.
294 very bad things might happen otherwise (usually segfaults).
295 - this module is not thread-safe. You must only ever use this module from
296 the same thread (this requirement might be loosened in the future to
297 allow per-thread schedulers, but Coro::State does not yet allow this).
298
203=head1 SEE ALSO 299=head1 SEE ALSO
204 300
205L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 301L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
206L<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>.
207 304
208=head1 AUTHOR 305=head1 AUTHOR
209 306
210 Marc Lehmann <pcg@goof.com> 307 Marc Lehmann <pcg@goof.com>
211 http://www.goof.com/pcg/marc/ 308 http://www.goof.com/pcg/marc/

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