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Comparing Coro/Coro.pm (file contents):
Revision 1.16 by root, Tue Jul 17 15:42:28 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 = 0.07; 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 $idle
91 112
92The coroutine to switch to when no other coroutine is running. The default 113The coroutine to switch to when no other coroutine is running. The default
93implementation prints "FATAL: deadlock detected" and exits. 114implementation prints "FATAL: deadlock detected" and exits.
… …
147 # should be done using priorities :( 168 # should be done using priorities :(
148 ($prev, $current) = ($current, shift @ready || $idle); 169 ($prev, $current) = ($current, shift @ready || $idle);
149 Coro::State::transfer($prev, $current); 170 Coro::State::transfer($prev, $current);
150} 171}
151 172
152=item yield 173=item cede
153 174
154Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
155ready 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.
156 178
157=cut 179=cut
158 180
159sub yield { 181sub cede {
160 $current->ready; 182 $current->ready;
161 &schedule; 183 &schedule;
162} 184}
163 185
164=item terminate 186=item terminate
… …
168Future versions of this function will allow result arguments. 190Future versions of this function will allow result arguments.
169 191
170=cut 192=cut
171 193
172sub terminate { 194sub terminate {
195 my $self = $current;
173 $current->{_results} = [@_]; 196 $self->{_results} = [@_];
174 &schedule; 197 $current = shift @ready || $idle;
198 Coro::State::transfer(delete $self->{_coro_state}, $current);
199 # cannot return
200 die;
175} 201}
176 202
177=back 203=back
178 204
179# dynamic methods 205# dynamic methods
… …
220 246
221=cut 247=cut
222 248
2231; 2491;
224 250
225=head1 BUGS 251=head1 BUGS/LIMITATIONS
226 252
227 - could be faster, especially when the core would introduce special 253 - could be faster, especially when the core would introduce special
228 support for coroutines (like it does for threads). 254 support for coroutines (like it does for threads).
229 - 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
230 identify. Could be as small as a single SV. 256 identify. Could be as small as a single SV.
231 - 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).
232 264
233=head1 SEE ALSO 265=head1 SEE ALSO
234 266
235L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 267L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
236L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 268L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.

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