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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 1.36 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
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 delete ((pop @destroy)->{_coro_state}) while @destroy;
124 &schedule;
125 }
126};
100 127
101# static methods. not really. 128# static methods. not really.
102 129
103=head2 STATIC METHODS 130=head2 STATIC METHODS
104 131
105Static methods are actually functions that operate on the current process only. 132Static methods are actually functions that operate on the current process only.
106 133
107=over 4 134=over 4
108 135
109=item async { ... }; 136=item async { ... } [@args...]
110 137
111Create a new asynchronous process and return it's process object 138Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 139(usually unused). When the sub returns the new process is automatically
113terminated. 140terminated.
114 141
115=cut 142 # create a new coroutine that just prints its arguments
143 async {
144 print "@_\n";
145 } 1,2,3,4;
116 146
147The coderef you submit MUST NOT be a closure that refers to variables
148in an outer scope. This does NOT work. Pass arguments into it instead.
149
150=cut
151
117sub async(&) { 152sub async(&@) {
118 my $pid = new Coro $_[0]; 153 my $pid = new Coro @_;
154 $manager->ready; # this ensures that the stack is cloned from the manager
119 $pid->ready; 155 $pid->ready;
120 $pid; 156 $pid;
121} 157}
122 158
123=item schedule 159=item schedule
… …
126into the ready queue, so calling this function usually means you will 162into the ready queue, so calling this function usually means you will
127never be called again. 163never be called again.
128 164
129=cut 165=cut
130 166
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 167=item cede
140 168
141Yield to other processes. This function puts the current process into the 169"Cede" to other processes. This function puts the current process into the
142ready 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.
143 172
144=cut 173=cut
145 174
146sub 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 {
147 $current->ready; 184 $current->cancel;
148 &schedule; 185 &schedule;
149} 186 die; # NORETURN
150
151=item terminate
152
153Terminates the current process.
154
155=cut
156
157sub terminate {
158 &schedule;
159} 187}
160 188
161=back 189=back
162 190
163# dynamic methods 191# dynamic methods
… …
166 194
167These are the methods you can call on process objects. 195These are the methods you can call on process objects.
168 196
169=over 4 197=over 4
170 198
171=item new Coro \&sub; 199=item new Coro \&sub [, @args...]
172 200
173Create a new process and return it. When the sub returns the process 201Create a new process and return it. When the sub returns the process
174automatically terminates. To start the process you must first put it into 202automatically terminates. To start the process you must first put it into
175the ready queue by calling the ready method. 203the ready queue by calling the ready method.
176 204
205The coderef you submit MUST NOT be a closure that refers to variables
206in an outer scope. This does NOT work. Pass arguments into it instead.
207
177=cut 208=cut
209
210sub _newcoro {
211 terminate &{+shift};
212}
178 213
179sub new { 214sub new {
180 my $class = shift; 215 my $class = shift;
181 my $proc = $_[0];
182 bless { 216 bless {
183 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 217 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
184 }, $class; 218 }, $class;
185} 219}
186 220
187=item $process->ready 221=item $process->ready
188 222
189Put the current process into the ready queue. 223Put the current process into the ready queue.
190 224
191=cut 225=cut
192 226
193sub ready { 227=item $process->cancel
228
229Like C<terminate>, but terminates the specified process instead.
230
231=cut
232
233sub cancel {
194 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];
195} 277}
196 278
197=back 279=back
198 280
199=cut 281=cut
200 282
2011; 2831;
202 284
285=head1 BUGS/LIMITATIONS
286
287 - you must make very sure that no coro is still active on global destruction.
288 very bad things might happen otherwise (usually segfaults).
289 - this module is not thread-safe. You must only ever use this module from
290 the same thread (this requirement might be loosened in the future to
291 allow per-thread schedulers, but Coro::State does not yet allow this).
292
203=head1 SEE ALSO 293=head1 SEE ALSO
204 294
205L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 295L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
206L<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>.
207 298
208=head1 AUTHOR 299=head1 AUTHOR
209 300
210 Marc Lehmann <pcg@goof.com> 301 Marc Lehmann <pcg@goof.com>
211 http://www.goof.com/pcg/marc/ 302 http://www.goof.com/pcg/marc/

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