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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 1.22 by root, Mon Jul 23 02:14:19 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+ @_ + $_ + $@ + $^W), that is, a coroutine has it's own callchain, it's
30own set of lexicals and it's own set of perl's most important global
31variables.
32
33WARNING: When using this module, make sure that, at program end, no
34coroutines are still running OR just call exit before falling off the
35end. The reason for this is that some coroutine of yours might have called
36into a C function, and falling off the end of main:: results in returning
37to that C function instead if to the main C interpreter.
38
39WARNING: Unless you really know what you are doing, do NOT do context
40switches inside callbacks from the XS level. The reason for this is
41similar to the reason above: A callback calls a perl function, this
42perl function does a context switch, some other callback is called, the
43original function returns from it - to what? To the wrong XS function,
44with totally different return values. Unfortunately, this includes
45callbacks done by perl itself (tie'd variables!).
46
47The only workaround for this is to do coroutines on C level.
48
28=cut 49=cut
29 50
30package Coro; 51package Coro;
31 52
32use Coro::State; 53use Coro::State;
33 54
34use base Exporter; 55use base Exporter;
35 56
36$VERSION = 0.05; 57$VERSION = 0.10;
37 58
38@EXPORT = qw(async yield schedule terminate); 59@EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($current); 60@EXPORT_OK = qw($current);
40 61
41{ 62{
42 use subs 'async';
43
44 my @async; 63 my @async;
45 64
46 # this way of handling attributes simply is NOT scalable ;() 65 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 66 sub import {
48 Coro->export_to_level(1, @_); 67 Coro->export_to_level(1, @_);
… …
52 my @attrs; 71 my @attrs;
53 for (@_) { 72 for (@_) {
54 if ($_ eq "Coro") { 73 if ($_ eq "Coro") {
55 push @async, $ref; 74 push @async, $ref;
56 } else { 75 } else {
57 push @attrs, @_; 76 push @attrs, $_;
58 } 77 }
59 } 78 }
60 return $old ? $old->($package, $name, @attrs) : @attrs; 79 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 80 };
62 } 81 }
63 82
64 sub INIT { 83 sub INIT {
65 async pop @async while @async; 84 &async(pop @async) while @async;
66 } 85 }
67} 86}
68 87
69=item $main 88=item $main
70 89
… …
72 91
73=cut 92=cut
74 93
75our $main = new Coro; 94our $main = new Coro;
76 95
77=item $current 96=item $current (or as function: current)
78 97
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 98The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 99
81=cut 100=cut
82 101
… …
84if ($current) { 103if ($current) {
85 $main->{specific} = $current->{specific}; 104 $main->{specific} = $current->{specific};
86} 105}
87 106
88our $current = $main; 107our $current = $main;
108
109sub current() { $current }
89 110
90=item $idle 111=item $idle
91 112
92The coroutine to switch to when no other coroutine is running. The default 113The coroutine to switch to when no other coroutine is running. The default
93implementation prints "FATAL: deadlock detected" and exits. 114implementation prints "FATAL: deadlock detected" and exits.
… …
99 print STDERR "FATAL: deadlock detected\n"; 120 print STDERR "FATAL: deadlock detected\n";
100 exit(51); 121 exit(51);
101}; 122};
102 123
103# we really need priorities... 124# we really need priorities...
104## my @ready; #d#
105our @ready = (); # the ready queue. hehe, rather broken ;) 125my @ready; # the ready queue. hehe, rather broken ;)
106 126
107# static methods. not really. 127# static methods. not really.
108 128
109=head2 STATIC METHODS 129=head2 STATIC METHODS
110 130
… …
148 # should be done using priorities :( 168 # should be done using priorities :(
149 ($prev, $current) = ($current, shift @ready || $idle); 169 ($prev, $current) = ($current, shift @ready || $idle);
150 Coro::State::transfer($prev, $current); 170 Coro::State::transfer($prev, $current);
151} 171}
152 172
153=item yield 173=item cede
154 174
155Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
156ready 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.
157 178
158=cut 179=cut
159 180
160sub yield { 181sub cede {
161 $current->ready; 182 $current->ready;
162 &schedule; 183 &schedule;
163} 184}
164 185
165=item terminate 186=item terminate
… …
169Future versions of this function will allow result arguments. 190Future versions of this function will allow result arguments.
170 191
171=cut 192=cut
172 193
173sub terminate { 194sub terminate {
195 my $self = $current;
174 $current->{_results} = [@_]; 196 $self->{_results} = [@_];
175 &schedule; 197 $current = shift @ready || $idle;
198 Coro::State::transfer(delete $self->{_coro_state}, $current);
199 # cannot return
200 die;
176} 201}
177 202
178=back 203=back
179 204
180# dynamic methods 205# dynamic methods
… …
221 246
222=cut 247=cut
223 248
2241; 2491;
225 250
226=head1 BUGS 251=head1 BUGS/LIMITATIONS
227 252
228 - could be faster, especially when the core would introduce special 253 - could be faster, especially when the core would introduce special
229 support for coroutines (like it does for threads). 254 support for coroutines (like it does for threads).
230 - there is still a memleak on coroutine termination that I could not 255 - there is still a memleak on coroutine termination that I could not
231 identify. Could be as small as a single SV. 256 identify. Could be as small as a single SV.
232 - this module is not well-tested. 257 - this module is not well-tested.
258 - if variables or arguments "disappear" (become undef) or become
259 corrupted please contact the author so he cen iron out the
260 remaining bugs.
261 - this module is not thread-safe. You must only ever use this module from
262 the same thread (this requirement might be loosened in the future to
263 allow per-thread schedulers, but Coro::State does not yet allow this).
233 264
234=head1 SEE ALSO 265=head1 SEE ALSO
235 266
236L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 267L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
237L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 268L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.

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