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Comparing Coro/Coro.pm (file contents):
Revision 1.9 by root, Sun Jul 15 02:35:52 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 (new Coro $_[0])->ready; 159 my $pid = new Coro @_;
160 $manager->ready; # this ensures that the stack is cloned from the manager
161 $pid->ready;
162 $pid;
119} 163}
120 164
121=item schedule 165=item schedule
122 166
123Calls the scheduler. Please note that the current process will not be put 167Calls the scheduler. Please note that the current process will not be put
124into the ready queue, so calling this function usually means you will 168into the ready queue, so calling this function usually means you will
125never be called again. 169never be called again.
126 170
127=cut 171=cut
128 172
129my $prev;
130
131sub schedule {
132 # should be done using priorities :(
133 ($prev, $current) = ($current, shift @ready || $idle);
134 Coro::State::transfer($prev, $current);
135}
136
137=item yield 173=item cede
138 174
139Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
140ready 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.
141 178
142=cut 179=cut
143 180
144sub 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 {
145 $current->ready; 190 $current->cancel;
146 &schedule; 191 &schedule;
147} 192 die; # NORETURN
148
149=item terminate
150
151Terminates the current process.
152
153=cut
154
155sub terminate {
156 &schedule;
157} 193}
158 194
159=back 195=back
160 196
161# dynamic methods 197# dynamic methods
… …
164 200
165These are the methods you can call on process objects. 201These are the methods you can call on process objects.
166 202
167=over 4 203=over 4
168 204
169=item new Coro \&sub; 205=item new Coro \&sub [, @args...]
170 206
171Create 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
172automatically terminates. To start the process you must first put it into 208automatically terminates. To start the process you must first put it into
173the ready queue by calling the ready method. 209the ready queue by calling the ready method.
174 210
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
175=cut 214=cut
215
216sub _newcoro {
217 terminate &{+shift};
218}
176 219
177sub new { 220sub new {
178 my $class = shift; 221 my $class = shift;
179 my $proc = $_[0];
180 bless { 222 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 223 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 224 }, $class;
183} 225}
184 226
185=item $process->ready 227=item $process->ready
186 228
187Put the current process into the ready queue. 229Put the given process into the ready queue.
188 230
189=cut 231=cut
190 232
191sub ready { 233=item $process->cancel
234
235Like C<terminate>, but terminates the specified process instead.
236
237=cut
238
239sub cancel {
192 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];
193} 283}
194 284
195=back 285=back
196 286
197=cut 287=cut
198 288
1991; 2891;
200 290
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
201=head1 SEE ALSO 299=head1 SEE ALSO
202 300
203L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 301L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
204L<Coro::Signal>, L<Coro::State>. 302L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
303L<Coro::Handle>, L<Coro::Socket>.
205 304
206=head1 AUTHOR 305=head1 AUTHOR
207 306
208 Marc Lehmann <pcg@goof.com> 307 Marc Lehmann <pcg@goof.com>
209 http://www.goof.com/pcg/marc/ 308 http://www.goof.com/pcg/marc/

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