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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 1.31 by root, Sat Aug 11 23:10:56 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$VERSION = 0.45;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 44%EXPORT_TAGS = (
45 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
46);
47@EXPORT_OK = @{$EXPORT_TAGS{prio}};
35 48
36{ 49{
37 use subs 'async';
38
39 my @async; 50 my @async;
51 my $init;
40 52
41 # this way of handling attributes simply is NOT scalable ;() 53 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 54 sub import {
43 Coro->export_to_level(1, @_); 55 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 56 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 58 my ($package, $ref) = (shift, shift);
47 my @attrs; 59 my @attrs;
48 for (@_) { 60 for (@_) {
49 if ($_ eq "Coro") { 61 if ($_ eq "Coro") {
50 push @async, $ref; 62 push @async, $ref;
63 unless ($init++) {
64 eval q{
65 sub INIT {
66 &async(pop @async) while @async;
67 }
68 };
69 }
51 } else { 70 } else {
52 push @attrs, @_; 71 push @attrs, $_;
53 } 72 }
54 } 73 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 74 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 75 };
57 } 76 }
58 77
59 sub INIT {
60 async pop @async while @async;
61 }
62} 78}
63 79
64=item $main 80=item $main
65 81
66This coroutine represents the main program. 82This coroutine represents the main program.
67 83
68=cut 84=cut
69 85
70our $main = new Coro; 86our $main = new Coro;
71 87
72=item $current 88=item $current (or as function: current)
73 89
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 90The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 91
76=cut 92=cut
77 93
… …
79if ($current) { 95if ($current) {
80 $main->{specific} = $current->{specific}; 96 $main->{specific} = $current->{specific};
81} 97}
82 98
83our $current = $main; 99our $current = $main;
100
101sub current() { $current }
84 102
85=item $idle 103=item $idle
86 104
87The coroutine to switch to when no other coroutine is running. The default 105The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 106implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 111our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 112 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 113 exit(51);
96}; 114};
97 115
98# we really need priorities... 116# this coroutine is necessary because a coroutine
99my @ready = (); # the ready queue. hehe, rather broken ;) 117# cannot destroy itself.
118my @destroy;
119my $manager = new Coro sub {
120 while() {
121 delete ((pop @destroy)->{_coro_state}) while @destroy;
122 &schedule;
123 }
124};
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
124into the ready queue, so calling this function usually means you will 160into the ready queue, so calling this function usually means you will
125never be called again. 161never be called again.
126 162
127=cut 163=cut
128 164
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 165=item cede
138 166
139Yield to other processes. This function puts the current process into the 167"Cede" to other processes. This function puts the current process into the
140ready queue and calls C<schedule>. 168ready queue and calls C<schedule>, which has the effect of giving up the
169current "timeslice" to other coroutines of the same or higher priority.
141 170
142=cut 171=cut
143 172
144sub yield { 173=item terminate
174
175Terminates the current process.
176
177Future versions of this function will allow result arguments.
178
179=cut
180
181sub terminate {
145 $current->ready; 182 $current->cancel;
146 &schedule; 183 &schedule;
147} 184 die; # NORETURN
148
149=item terminate
150
151Terminates the current process.
152
153=cut
154
155sub terminate {
156 &schedule;
157} 185}
158 186
159=back 187=back
160 188
161# dynamic methods 189# dynamic methods
… …
164 192
165These are the methods you can call on process objects. 193These are the methods you can call on process objects.
166 194
167=over 4 195=over 4
168 196
169=item new Coro \&sub; 197=item new Coro \&sub [, @args...]
170 198
171Create a new process and return it. When the sub returns the process 199Create a new process and return it. When the sub returns the process
172automatically terminates. To start the process you must first put it into 200automatically terminates. To start the process you must first put it into
173the ready queue by calling the ready method. 201the ready queue by calling the ready method.
174 202
203The coderef you submit MUST NOT be a closure that refers to variables
204in an outer scope. This does NOT work. Pass arguments into it instead.
205
175=cut 206=cut
207
208sub _newcoro {
209 terminate &{+shift};
210}
176 211
177sub new { 212sub new {
178 my $class = shift; 213 my $class = shift;
179 my $proc = $_[0];
180 bless { 214 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 215 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 216 }, $class;
183} 217}
184 218
185=item $process->ready 219=item $process->ready
186 220
187Put the current process into the ready queue. 221Put the current process into the ready queue.
188 222
189=cut 223=cut
190 224
191sub ready { 225=item $process->cancel
226
227Like C<terminate>, but terminates the specified process instead.
228
229=cut
230
231sub cancel {
192 push @ready, $_[0]; 232 push @destroy, $_[0];
233 $manager->ready;
234}
235
236=item $oldprio = $process->prio($newprio)
237
238Sets the priority of the process. Higher priority processes get run before
239lower priority processes. Priorities are smalled signed integer (currently
240-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
241tag :prio to get then):
242
243 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
244 3 > 1 > 0 > -1 > -3 > -4
245
246 # set priority to HIGH
247 current->prio(PRIO_HIGH);
248
249The idle coroutine ($Coro::idle) always has a lower priority than any
250existing coroutine.
251
252Changing the priority of the current process will take effect immediately,
253but changing the priority of processes in the ready queue (but not
254running) will only take effect after the next schedule (of that
255process). This is a bug that will be fixed in some future version.
256
257=cut
258
259sub prio {
260 my $old = $_[0]{prio};
261 $_[0]{prio} = $_[1] if @_ > 1;
262 $old;
263}
264
265=item $newprio = $process->nice($change)
266
267Similar to C<prio>, but subtract the given value from the priority (i.e.
268higher values mean lower priority, just as in unix).
269
270=cut
271
272sub nice {
273 $_[0]{prio} -= $_[1];
193} 274}
194 275
195=back 276=back
196 277
197=cut 278=cut
198 279
1991; 2801;
200 281
282=head1 BUGS/LIMITATIONS
283
284 - could be faster, especially when the core would introduce special
285 support for coroutines (like it does for threads).
286 - there is still a memleak on coroutine termination that I could not
287 identify. Could be as small as a single SV.
288 - this module is not well-tested.
289 - if variables or arguments "disappear" (become undef) or become
290 corrupted please contact the author so he cen iron out the
291 remaining bugs.
292 - this module is not thread-safe. You must only ever use this module from
293 the same thread (this requirement might be loosened in the future to
294 allow per-thread schedulers, but Coro::State does not yet allow this).
295
201=head1 SEE ALSO 296=head1 SEE ALSO
202 297
203L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 298L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
204L<Coro::Signal>, L<Coro::State>. 299L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
300L<Coro::Handle>, L<Coro::Socket>.
205 301
206=head1 AUTHOR 302=head1 AUTHOR
207 303
208 Marc Lehmann <pcg@goof.com> 304 Marc Lehmann <pcg@goof.com>
209 http://www.goof.com/pcg/marc/ 305 http://www.goof.com/pcg/marc/

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