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Comparing Coro/Coro.pm (file contents):
Revision 1.78 by root, Wed Nov 1 01:21:21 2006 UTC vs.
Revision 1.91 by root, Fri Dec 1 02:17:37 2006 UTC

35use strict; 35use strict;
36no warnings "uninitialized"; 36no warnings "uninitialized";
37 37
38use Coro::State; 38use Coro::State;
39 39
40use base Exporter::; 40use base qw(Coro::State Exporter);
41 41
42our $idle; # idle coroutine 42our $idle; # idle handler
43our $main; # main coroutine 43our $main; # main coroutine
44our $current; # current coroutine 44our $current; # current coroutine
45 45
46our $VERSION = '2.1'; 46our $VERSION = '3.0';
47 47
48our @EXPORT = qw(async cede schedule terminate current); 48our @EXPORT = qw(async cede schedule terminate current);
49our %EXPORT_TAGS = ( 49our %EXPORT_TAGS = (
50 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 50 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
51); 51);
95 95
96$main = new Coro; 96$main = new Coro;
97 97
98=item $current (or as function: current) 98=item $current (or as function: current)
99 99
100The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 100The current coroutine (the last coroutine switched to). The initial value
101is C<$main> (of course).
102
103This variable is B<strictly> I<read-only>. It is provided for performance
104reasons. If performance is not essentiel you are encouraged to use the
105C<Coro::current> function instead.
101 106
102=cut 107=cut
103 108
104# maybe some other module used Coro::Specific before... 109# maybe some other module used Coro::Specific before...
105if ($current) { 110if ($current) {
110 115
111sub current() { $current } 116sub current() { $current }
112 117
113=item $idle 118=item $idle
114 119
115The coroutine to switch to when no other coroutine is running. The default 120A callback that is called whenever the scheduler finds no ready coroutines
116implementation prints "FATAL: deadlock detected" and exits. 121to run. The default implementation prints "FATAL: deadlock detected" and
122exits, because the program has no other way to continue.
117 123
118=cut 124This hook is overwritten by modules such as C<Coro::Timer> and
125C<Coro::Event> to wait on an external event that hopefully wake up a
126coroutine so the scheduler can run it.
119 127
120# should be done using priorities :( 128Please note that if your callback recursively invokes perl (e.g. for event
121$idle = new Coro sub { 129handlers), then it must be prepared to be called recursively.
130
131=cut
132
133$idle = sub {
122 print STDERR "FATAL: deadlock detected\n"; 134 print STDERR "FATAL: deadlock detected\n";
123 exit(51); 135 exit (51);
124}; 136};
125 137
126# this coroutine is necessary because a coroutine 138# this coroutine is necessary because a coroutine
127# cannot destroy itself. 139# cannot destroy itself.
128my @destroy; 140my @destroy;
129my $manager;
130$manager = new Coro sub { 141my $manager; $manager = new Coro sub {
131 while () { 142 while () {
132 # by overwriting the state object with the manager we destroy it 143 # by overwriting the state object with the manager we destroy it
133 # while still being able to schedule this coroutine (in case it has 144 # while still being able to schedule this coroutine (in case it has
134 # been readied multiple times. this is harmless since the manager 145 # been readied multiple times. this is harmless since the manager
135 # can be called as many times as neccessary and will always 146 # can be called as many times as neccessary and will always
137 while (@destroy) { 148 while (@destroy) {
138 my $coro = pop @destroy; 149 my $coro = pop @destroy;
139 $coro->{status} ||= []; 150 $coro->{status} ||= [];
140 $_->ready for @{delete $coro->{join} || []}; 151 $_->ready for @{delete $coro->{join} || []};
141 152
142 # the next line destroys the _coro_state, but keeps the 153 # the next line destroys the coro state, but keeps the
143 # process itself intact (we basically make it a zombie 154 # process itself intact (we basically make it a zombie
144 # process that always runs the manager thread, so it's possible 155 # process that always runs the manager thread, so it's possible
145 # to transfer() to this process). 156 # to transfer() to this process).
146 $coro->{_coro_state} = $manager->{_coro_state}; 157 $coro->_clone_state_from ($manager);
147 } 158 }
148 &schedule; 159 &schedule;
149 } 160 }
150}; 161};
151 162
163 174
164Create a new asynchronous process and return it's process object 175Create a new asynchronous process and return it's process object
165(usually unused). When the sub returns the new process is automatically 176(usually unused). When the sub returns the new process is automatically
166terminated. 177terminated.
167 178
179Calling C<exit> in a coroutine will not work correctly, so do not do that.
180
181When the coroutine dies, the program will exit, just as in the main
182program.
183
168 # create a new coroutine that just prints its arguments 184 # create a new coroutine that just prints its arguments
169 async { 185 async {
170 print "@_\n"; 186 print "@_\n";
171 } 1,2,3,4; 187 } 1,2,3,4;
172 188
173=cut 189=cut
174 190
175sub async(&@) { 191sub async(&@) {
176 my $pid = new Coro @_; 192 my $pid = new Coro @_;
177 $manager->ready; # this ensures that the stack is cloned from the manager
178 $pid->ready; 193 $pid->ready;
179 $pid; 194 $pid
180} 195}
181 196
182=item schedule 197=item schedule
183 198
184Calls the scheduler. Please note that the current process will not be put 199Calls the scheduler. Please note that the current process will not be put
185into the ready queue, so calling this function usually means you will 200into the ready queue, so calling this function usually means you will
186never be called again. 201never be called again unless something else (e.g. an event handler) calls
202ready.
203
204The canonical way to wait on external events is this:
205
206 {
207 # remember current process
208 my $current = $Coro::current;
209
210 # register a hypothetical event handler
211 on_event_invoke sub {
212 # wake up sleeping coroutine
213 $current->ready;
214 undef $current;
215 };
216
217 # call schedule until event occured.
218 # in case we are woken up for other reasons
219 # (current still defined), loop.
220 Coro::schedule while $current;
221 }
187 222
188=cut 223=cut
189 224
190=item cede 225=item cede
191 226
220Create a new process and return it. When the sub returns the process 255Create a new process and return it. When the sub returns the process
221automatically terminates as if C<terminate> with the returned values were 256automatically terminates as if C<terminate> with the returned values were
222called. To make the process run you must first put it into the ready queue 257called. To make the process run you must first put it into the ready queue
223by calling the ready method. 258by calling the ready method.
224 259
225=cut 260Calling C<exit> in a coroutine will not work correctly, so do not do that.
226 261
262=cut
263
227sub _newcoro { 264sub _new_coro {
228 terminate &{+shift}; 265 terminate &{+shift};
229} 266}
230 267
231sub new { 268sub new {
232 my $class = shift; 269 my $class = shift;
233 bless {
234 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
235 }, $class;
236}
237 270
271 $class->SUPER::new (\&_new_coro, @_)
272}
273
238=item $process->ready 274=item $success = $process->ready
239 275
240Put the given process into the ready queue. 276Put the given process into the ready queue (according to it's priority)
277and return true. If the process is already in the ready queue, do nothing
278and return false.
241 279
242=cut 280=item $is_ready = $process->is_ready
281
282Return wether the process is currently the ready queue or not,
243 283
244=item $process->cancel (arg...) 284=item $process->cancel (arg...)
245 285
246Temrinates the given process and makes it return the given arguments as 286Terminates the given process and makes it return the given arguments as
247status (default: the empty list). 287status (default: the empty list).
248 288
249=cut 289=cut
250 290
251sub cancel { 291sub cancel {
271 &schedule; 311 &schedule;
272 } 312 }
273 wantarray ? @{$self->{status}} : $self->{status}[0]; 313 wantarray ? @{$self->{status}} : $self->{status}[0];
274} 314}
275 315
276=item $oldprio = $process->prio($newprio) 316=item $oldprio = $process->prio ($newprio)
277 317
278Sets (or gets, if the argument is missing) the priority of the 318Sets (or gets, if the argument is missing) the priority of the
279process. Higher priority processes get run before lower priority 319process. Higher priority processes get run before lower priority
280processes. Priorities are small signed integers (currently -4 .. +3), 320processes. Priorities are small signed integers (currently -4 .. +3),
281that you can refer to using PRIO_xxx constants (use the import tag :prio 321that you can refer to using PRIO_xxx constants (use the import tag :prio
293Changing the priority of the current process will take effect immediately, 333Changing the priority of the current process will take effect immediately,
294but changing the priority of processes in the ready queue (but not 334but changing the priority of processes in the ready queue (but not
295running) will only take effect after the next schedule (of that 335running) will only take effect after the next schedule (of that
296process). This is a bug that will be fixed in some future version. 336process). This is a bug that will be fixed in some future version.
297 337
298=cut
299
300sub prio {
301 my $old = $_[0]{prio};
302 $_[0]{prio} = $_[1] if @_ > 1;
303 $old;
304}
305
306=item $newprio = $process->nice($change) 338=item $newprio = $process->nice ($change)
307 339
308Similar to C<prio>, but subtract the given value from the priority (i.e. 340Similar to C<prio>, but subtract the given value from the priority (i.e.
309higher values mean lower priority, just as in unix). 341higher values mean lower priority, just as in unix).
310 342
311=cut
312
313sub nice {
314 $_[0]{prio} -= $_[1];
315}
316
317=item $olddesc = $process->desc($newdesc) 343=item $olddesc = $process->desc ($newdesc)
318 344
319Sets (or gets in case the argument is missing) the description for this 345Sets (or gets in case the argument is missing) the description for this
320process. This is just a free-form string you can associate with a process. 346process. This is just a free-form string you can associate with a process.
321 347
322=cut 348=cut

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