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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 1.28 by root, Fri Aug 10 21:03:40 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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
27use Coro::State; 37use Coro::State;
28 38
29use base Exporter; 39use base Exporter;
30 40
31$VERSION = 0.04; 41$VERSION = 0.13;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 44@EXPORT_OK = qw($current);
35 45
36{ 46{
37 use subs 'async';
38
39 my @async; 47 my @async;
48 my $init;
40 49
41 # this way of handling attributes simply is NOT scalable ;() 50 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 51 sub import {
43 Coro->export_to_level(1, @_); 52 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 53 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 55 my ($package, $ref) = (shift, shift);
47 my @attrs; 56 my @attrs;
48 for (@_) { 57 for (@_) {
49 if ($_ eq "Coro") { 58 if ($_ eq "Coro") {
50 push @async, $ref; 59 push @async, $ref;
60 unless ($init++) {
61 eval q{
62 sub INIT {
63 &async(pop @async) while @async;
64 }
65 };
66 }
51 } else { 67 } else {
52 push @attrs, @_; 68 push @attrs, $_;
53 } 69 }
54 } 70 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 71 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 72 };
57 } 73 }
58 74
59 sub INIT {
60 async pop @async while @async;
61 }
62} 75}
63 76
64=item $main 77=item $main
65 78
66This coroutine represents the main program. 79This coroutine represents the main program.
67 80
68=cut 81=cut
69 82
70our $main = new Coro; 83our $main = new Coro;
71 84
72=item $current 85=item $current (or as function: current)
73 86
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 87The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 88
76=cut 89=cut
77 90
… …
79if ($current) { 92if ($current) {
80 $main->{specific} = $current->{specific}; 93 $main->{specific} = $current->{specific};
81} 94}
82 95
83our $current = $main; 96our $current = $main;
97
98sub current() { $current }
84 99
85=item $idle 100=item $idle
86 101
87The coroutine to switch to when no other coroutine is running. The default 102The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 103implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 108our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 109 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 110 exit(51);
96}; 111};
97 112
113# this coroutine is necessary because a coroutine
114# cannot destroy itself.
115my @destroy;
116my $manager = new Coro sub {
117 while() {
118 delete ((pop @destroy)->{_coro_state}) while @destroy;
119 &schedule;
120 }
121};
122
98# we really need priorities... 123# we really need priorities...
99my @ready = (); # the ready queue. hehe, rather broken ;) 124my @ready; # the ready queue. hehe, rather broken ;)
100 125
101# static methods. not really. 126# static methods. not really.
102 127
103=head2 STATIC METHODS 128=head2 STATIC METHODS
104 129
105Static methods are actually functions that operate on the current process only. 130Static methods are actually functions that operate on the current process only.
106 131
107=over 4 132=over 4
108 133
109=item async { ... }; 134=item async { ... } [@args...]
110 135
111Create a new asynchronous process and return it's process object 136Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 137(usually unused). When the sub returns the new process is automatically
113terminated. 138terminated.
114 139
115=cut 140 # create a new coroutine that just prints its arguments
141 async {
142 print "@_\n";
143 } 1,2,3,4;
116 144
145The coderef you submit MUST NOT be a closure that refers to variables
146in an outer scope. This does NOT work. Pass arguments into it instead.
147
148=cut
149
117sub async(&) { 150sub async(&@) {
118 (new Coro $_[0])->ready; 151 my $pid = new Coro @_;
152 $manager->ready; # this ensures that the stack is cloned from the manager
153 $pid->ready;
154 $pid;
119} 155}
120 156
121=item schedule 157=item schedule
122 158
123Calls the scheduler. Please note that the current process will not be put 159Calls the scheduler. Please note that the current process will not be put
… …
132 # should be done using priorities :( 168 # should be done using priorities :(
133 ($prev, $current) = ($current, shift @ready || $idle); 169 ($prev, $current) = ($current, shift @ready || $idle);
134 Coro::State::transfer($prev, $current); 170 Coro::State::transfer($prev, $current);
135} 171}
136 172
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 { 181sub cede {
145 $current->ready; 182 $current->ready;
146 &schedule; 183 &schedule;
147} 184}
148 185
149=item terminate 186=item terminate
150 187
151Terminates the current process. 188Terminates the current process.
152 189
190Future versions of this function will allow result arguments.
191
153=cut 192=cut
154 193
155sub terminate { 194sub terminate {
195 $current->cancel;
156 &schedule; 196 &schedule;
197 die; # NORETURN
157} 198}
158 199
159=back 200=back
160 201
161# dynamic methods 202# dynamic methods
… …
164 205
165These are the methods you can call on process objects. 206These are the methods you can call on process objects.
166 207
167=over 4 208=over 4
168 209
169=item new Coro \&sub; 210=item new Coro \&sub [, @args...]
170 211
171Create a new process and return it. When the sub returns the process 212Create a new process and return it. When the sub returns the process
172automatically terminates. To start the process you must first put it into 213automatically terminates. To start the process you must first put it into
173the ready queue by calling the ready method. 214the ready queue by calling the ready method.
174 215
216The coderef you submit MUST NOT be a closure that refers to variables
217in an outer scope. This does NOT work. Pass arguments into it instead.
218
175=cut 219=cut
220
221sub _newcoro {
222 terminate &{+shift};
223}
176 224
177sub new { 225sub new {
178 my $class = shift; 226 my $class = shift;
179 my $proc = $_[0];
180 bless { 227 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 228 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 229 }, $class;
183} 230}
184 231
185=item $process->ready 232=item $process->ready
186 233
… …
190 237
191sub ready { 238sub ready {
192 push @ready, $_[0]; 239 push @ready, $_[0];
193} 240}
194 241
242=item $process->cancel
243
244Like C<terminate>, but terminates the specified process instead.
245
246=cut
247
248sub cancel {
249 push @destroy, $_[0];
250 $manager->ready;
251}
252
195=back 253=back
196 254
197=cut 255=cut
198 256
1991; 2571;
200 258
259=head1 BUGS/LIMITATIONS
260
261 - could be faster, especially when the core would introduce special
262 support for coroutines (like it does for threads).
263 - there is still a memleak on coroutine termination that I could not
264 identify. Could be as small as a single SV.
265 - this module is not well-tested.
266 - if variables or arguments "disappear" (become undef) or become
267 corrupted please contact the author so he cen iron out the
268 remaining bugs.
269 - this module is not thread-safe. You must only ever use this module from
270 the same thread (this requirement might be loosened in the future to
271 allow per-thread schedulers, but Coro::State does not yet allow this).
272
201=head1 SEE ALSO 273=head1 SEE ALSO
202 274
203L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 275L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
204L<Coro::Signal>, L<Coro::State>. 276L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
277L<Coro::Handle>, L<Coro::Socket>.
205 278
206=head1 AUTHOR 279=head1 AUTHOR
207 280
208 Marc Lehmann <pcg@goof.com> 281 Marc Lehmann <pcg@goof.com>
209 http://www.goof.com/pcg/marc/ 282 http://www.goof.com/pcg/marc/

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