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Comparing Coro/Coro.pm (file contents):
Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC vs.
Revision 1.29 by root, Sat Aug 11 00:37:31 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 = 0.05; 41$VERSION = 0.45;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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 my $pid = new Coro $_[0]; 151 my $pid = new Coro @_;
152 $manager->ready; # this ensures that the stack is cloned from the manager
119 $pid->ready; 153 $pid->ready;
120 $pid; 154 $pid;
121} 155}
122 156
123=item schedule 157=item schedule
… …
129=cut 163=cut
130 164
131my $prev; 165my $prev;
132 166
133sub schedule { 167sub schedule {
134 local @_;
135 # should be done using priorities :( 168 # should be done using priorities :(
136 ($prev, $current) = ($current, shift @ready || $idle); 169 ($prev, $current) = ($current, shift @ready || $idle);
137 Coro::State::transfer($prev, $current); 170 Coro::State::transfer($prev, $current);
138} 171}
139 172
140=item yield 173=item cede
141 174
142Yield to other processes. This function puts the current process into the 175"Cede" to other processes. This function puts the current process into the
143ready 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.
144 178
145=cut 179=cut
146 180
147sub yield { 181sub cede {
148 $current->ready; 182 $current->ready;
149 &schedule; 183 &schedule;
150} 184}
151 185
152=item terminate 186=item terminate
153 187
154Terminates the current process. 188Terminates the current process.
155 189
190Future versions of this function will allow result arguments.
191
156=cut 192=cut
157 193
158sub terminate { 194sub terminate {
195 $current->cancel;
159 &schedule; 196 &schedule;
197 die; # NORETURN
160} 198}
161 199
162=back 200=back
163 201
164# dynamic methods 202# dynamic methods
… …
167 205
168These are the methods you can call on process objects. 206These are the methods you can call on process objects.
169 207
170=over 4 208=over 4
171 209
172=item new Coro \&sub; 210=item new Coro \&sub [, @args...]
173 211
174Create 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
175automatically terminates. To start the process you must first put it into 213automatically terminates. To start the process you must first put it into
176the ready queue by calling the ready method. 214the ready queue by calling the ready method.
177 215
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
178=cut 219=cut
220
221sub _newcoro {
222 terminate &{+shift};
223}
179 224
180sub new { 225sub new {
181 my $class = shift; 226 my $class = shift;
182 my $proc = $_[0];
183 bless { 227 bless {
184 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 228 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
185 }, $class; 229 }, $class;
186} 230}
187 231
188=item $process->ready 232=item $process->ready
189 233
… …
193 237
194sub ready { 238sub ready {
195 push @ready, $_[0]; 239 push @ready, $_[0];
196} 240}
197 241
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
198=back 253=back
199 254
200=cut 255=cut
201 256
2021; 2571;
203 258
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
204=head1 SEE ALSO 273=head1 SEE ALSO
205 274
206L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 275L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
207L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 276L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
277L<Coro::Handle>, L<Coro::Socket>.
208 278
209=head1 AUTHOR 279=head1 AUTHOR
210 280
211 Marc Lehmann <pcg@goof.com> 281 Marc Lehmann <pcg@goof.com>
212 http://www.goof.com/pcg/marc/ 282 http://www.goof.com/pcg/marc/

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