… | |
… | |
24 | Threads but don't run in parallel. |
24 | Threads but don't run in parallel. |
25 | |
25 | |
26 | This module is still experimental, see the BUGS section below. |
26 | This module is still experimental, see the BUGS section below. |
27 | |
27 | |
28 | In this module, coroutines are defined as "callchain + lexical variables |
28 | In this module, coroutines are defined as "callchain + lexical variables |
29 | + @_ + $_ + $@ + $^W), that is, a coroutine has it's own callchain, it's |
29 | + @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own |
30 | own set of lexicals and it's own set of perl's most important global |
30 | callchain, it's own set of lexicals and it's own set of perl's most |
31 | variables. |
31 | important global variables. |
32 | |
|
|
33 | WARNING: When using this module, make sure that, at program end, no |
|
|
34 | coroutines are still running OR just call exit before falling off the |
|
|
35 | end. The reason for this is that some coroutine of yours might have called |
|
|
36 | into a C function, and falling off the end of main:: results in returning |
|
|
37 | to that C function instead if to the main C interpreter. |
|
|
38 | |
|
|
39 | WARNING: Unless you really know what you are doing, do NOT do context |
|
|
40 | switches inside callbacks from the XS level. The reason for this is |
|
|
41 | similar to the reason above: A callback calls a perl function, this |
|
|
42 | perl function does a context switch, some other callback is called, the |
|
|
43 | original function returns from it - to what? To the wrong XS function, |
|
|
44 | with totally different return values. Unfortunately, this includes |
|
|
45 | callbacks done by perl itself (tie'd variables!). |
|
|
46 | |
|
|
47 | The only workaround for this is to do coroutines on C level. |
|
|
48 | |
32 | |
49 | =cut |
33 | =cut |
50 | |
34 | |
51 | package Coro; |
35 | package Coro; |
52 | |
36 | |
|
|
37 | no warnings qw(uninitialized); |
|
|
38 | |
53 | use Coro::State; |
39 | use Coro::State; |
54 | |
40 | |
55 | use base Exporter; |
41 | use base Exporter; |
56 | |
42 | |
57 | $VERSION = 0.10; |
43 | $VERSION = 0.51; |
58 | |
44 | |
59 | @EXPORT = qw(async cede schedule terminate current); |
45 | @EXPORT = qw(async cede schedule terminate current); |
60 | @EXPORT_OK = qw($current); |
46 | %EXPORT_TAGS = ( |
|
|
47 | prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], |
|
|
48 | ); |
|
|
49 | @EXPORT_OK = @{$EXPORT_TAGS{prio}}; |
61 | |
50 | |
62 | { |
51 | { |
63 | my @async; |
52 | my @async; |
|
|
53 | my $init; |
64 | |
54 | |
65 | # this way of handling attributes simply is NOT scalable ;() |
55 | # this way of handling attributes simply is NOT scalable ;() |
66 | sub import { |
56 | sub import { |
67 | Coro->export_to_level(1, @_); |
57 | Coro->export_to_level(1, @_); |
68 | my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
58 | my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
… | |
… | |
70 | my ($package, $ref) = (shift, shift); |
60 | my ($package, $ref) = (shift, shift); |
71 | my @attrs; |
61 | my @attrs; |
72 | for (@_) { |
62 | for (@_) { |
73 | if ($_ eq "Coro") { |
63 | if ($_ eq "Coro") { |
74 | push @async, $ref; |
64 | push @async, $ref; |
|
|
65 | unless ($init++) { |
|
|
66 | eval q{ |
|
|
67 | sub INIT { |
|
|
68 | &async(pop @async) while @async; |
|
|
69 | } |
|
|
70 | }; |
|
|
71 | } |
75 | } else { |
72 | } else { |
76 | push @attrs, $_; |
73 | push @attrs, $_; |
77 | } |
74 | } |
78 | } |
75 | } |
79 | return $old ? $old->($package, $ref, @attrs) : @attrs; |
76 | return $old ? $old->($package, $ref, @attrs) : @attrs; |
80 | }; |
77 | }; |
81 | } |
78 | } |
82 | |
79 | |
83 | sub INIT { |
|
|
84 | &async(pop @async) while @async; |
|
|
85 | } |
|
|
86 | } |
80 | } |
87 | |
81 | |
88 | =item $main |
82 | =item $main |
89 | |
83 | |
90 | This coroutine represents the main program. |
84 | This coroutine represents the main program. |
… | |
… | |
119 | our $idle = new Coro sub { |
113 | our $idle = new Coro sub { |
120 | print STDERR "FATAL: deadlock detected\n"; |
114 | print STDERR "FATAL: deadlock detected\n"; |
121 | exit(51); |
115 | exit(51); |
122 | }; |
116 | }; |
123 | |
117 | |
124 | # we really need priorities... |
118 | # this coroutine is necessary because a coroutine |
125 | my @ready; # the ready queue. hehe, rather broken ;) |
119 | # cannot destroy itself. |
|
|
120 | my @destroy; |
|
|
121 | my $manager; |
|
|
122 | $manager = new Coro sub { |
|
|
123 | while() { |
|
|
124 | # by overwriting the state object with the manager we destroy it |
|
|
125 | # while still being able to schedule this coroutine (in case it has |
|
|
126 | # been readied multiple times. this is harmless since the manager |
|
|
127 | # can be called as many times as neccessary and will always |
|
|
128 | # remove itself from the runqueue |
|
|
129 | (pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy; |
|
|
130 | &schedule; |
|
|
131 | } |
|
|
132 | }; |
126 | |
133 | |
127 | # static methods. not really. |
134 | # static methods. not really. |
128 | |
135 | |
129 | =head2 STATIC METHODS |
136 | =head2 STATIC METHODS |
130 | |
137 | |
… | |
… | |
148 | |
155 | |
149 | =cut |
156 | =cut |
150 | |
157 | |
151 | sub async(&@) { |
158 | sub async(&@) { |
152 | my $pid = new Coro @_; |
159 | my $pid = new Coro @_; |
|
|
160 | $manager->ready; # this ensures that the stack is cloned from the manager |
153 | $pid->ready; |
161 | $pid->ready; |
154 | $pid; |
162 | $pid; |
155 | } |
163 | } |
156 | |
164 | |
157 | =item schedule |
165 | =item schedule |
… | |
… | |
160 | into the ready queue, so calling this function usually means you will |
168 | into the ready queue, so calling this function usually means you will |
161 | never be called again. |
169 | never be called again. |
162 | |
170 | |
163 | =cut |
171 | =cut |
164 | |
172 | |
165 | my $prev; |
|
|
166 | |
|
|
167 | sub schedule { |
|
|
168 | # should be done using priorities :( |
|
|
169 | ($prev, $current) = ($current, shift @ready || $idle); |
|
|
170 | Coro::State::transfer($prev, $current); |
|
|
171 | } |
|
|
172 | |
|
|
173 | =item cede |
173 | =item cede |
174 | |
174 | |
175 | "Cede" to other processes. This function puts the current process into the |
175 | "Cede" to other processes. This function puts the current process into the |
176 | ready queue and calls C<schedule>, which has the effect of giving up the |
176 | ready queue and calls C<schedule>, which has the effect of giving up the |
177 | current "timeslice" to other coroutines of the same or higher priority. |
177 | current "timeslice" to other coroutines of the same or higher priority. |
178 | |
178 | |
179 | =cut |
179 | =cut |
180 | |
180 | |
181 | sub cede { |
181 | =item terminate |
|
|
182 | |
|
|
183 | Terminates the current process. |
|
|
184 | |
|
|
185 | Future versions of this function will allow result arguments. |
|
|
186 | |
|
|
187 | =cut |
|
|
188 | |
|
|
189 | sub terminate { |
182 | $current->ready; |
190 | $current->cancel; |
183 | &schedule; |
191 | &schedule; |
184 | } |
192 | die; # NORETURN |
185 | |
|
|
186 | =item terminate |
|
|
187 | |
|
|
188 | Terminates the current process. |
|
|
189 | |
|
|
190 | Future versions of this function will allow result arguments. |
|
|
191 | |
|
|
192 | =cut |
|
|
193 | |
|
|
194 | sub terminate { |
|
|
195 | my $self = $current; |
|
|
196 | $self->{_results} = [@_]; |
|
|
197 | $current = shift @ready || $idle; |
|
|
198 | Coro::State::transfer(delete $self->{_coro_state}, $current); |
|
|
199 | # cannot return |
|
|
200 | die; |
|
|
201 | } |
193 | } |
202 | |
194 | |
203 | =back |
195 | =back |
204 | |
196 | |
205 | # dynamic methods |
197 | # dynamic methods |
… | |
… | |
232 | }, $class; |
224 | }, $class; |
233 | } |
225 | } |
234 | |
226 | |
235 | =item $process->ready |
227 | =item $process->ready |
236 | |
228 | |
237 | Put the current process into the ready queue. |
229 | Put the given process into the ready queue. |
238 | |
230 | |
239 | =cut |
231 | =cut |
240 | |
232 | |
241 | sub ready { |
233 | =item $process->cancel |
|
|
234 | |
|
|
235 | Like C<terminate>, but terminates the specified process instead. |
|
|
236 | |
|
|
237 | =cut |
|
|
238 | |
|
|
239 | sub cancel { |
242 | push @ready, $_[0]; |
240 | push @destroy, $_[0]; |
|
|
241 | $manager->ready; |
|
|
242 | &schedule if $current == $_[0]; |
|
|
243 | } |
|
|
244 | |
|
|
245 | =item $oldprio = $process->prio($newprio) |
|
|
246 | |
|
|
247 | Sets the priority of the process. Higher priority processes get run before |
|
|
248 | lower priority processes. Priorities are smalled signed integer (currently |
|
|
249 | -4 .. +3), that you can refer to using PRIO_xxx constants (use the import |
|
|
250 | tag :prio to get then): |
|
|
251 | |
|
|
252 | PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
|
|
253 | 3 > 1 > 0 > -1 > -3 > -4 |
|
|
254 | |
|
|
255 | # set priority to HIGH |
|
|
256 | current->prio(PRIO_HIGH); |
|
|
257 | |
|
|
258 | The idle coroutine ($Coro::idle) always has a lower priority than any |
|
|
259 | existing coroutine. |
|
|
260 | |
|
|
261 | Changing the priority of the current process will take effect immediately, |
|
|
262 | but changing the priority of processes in the ready queue (but not |
|
|
263 | running) will only take effect after the next schedule (of that |
|
|
264 | process). This is a bug that will be fixed in some future version. |
|
|
265 | |
|
|
266 | =cut |
|
|
267 | |
|
|
268 | sub prio { |
|
|
269 | my $old = $_[0]{prio}; |
|
|
270 | $_[0]{prio} = $_[1] if @_ > 1; |
|
|
271 | $old; |
|
|
272 | } |
|
|
273 | |
|
|
274 | =item $newprio = $process->nice($change) |
|
|
275 | |
|
|
276 | Similar to C<prio>, but subtract the given value from the priority (i.e. |
|
|
277 | higher values mean lower priority, just as in unix). |
|
|
278 | |
|
|
279 | =cut |
|
|
280 | |
|
|
281 | sub nice { |
|
|
282 | $_[0]{prio} -= $_[1]; |
243 | } |
283 | } |
244 | |
284 | |
245 | =back |
285 | =back |
246 | |
286 | |
247 | =cut |
287 | =cut |
248 | |
288 | |
249 | 1; |
289 | 1; |
250 | |
290 | |
251 | =head1 BUGS/LIMITATIONS |
291 | =head1 BUGS/LIMITATIONS |
252 | |
292 | |
253 | - could be faster, especially when the core would introduce special |
293 | - you must make very sure that no coro is still active on global destruction. |
254 | support for coroutines (like it does for threads). |
294 | very bad things might happen otherwise (usually segfaults). |
255 | - there is still a memleak on coroutine termination that I could not |
|
|
256 | identify. Could be as small as a single SV. |
|
|
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 |
295 | - 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 |
296 | 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). |
297 | allow per-thread schedulers, but Coro::State does not yet allow this). |
264 | |
298 | |
265 | =head1 SEE ALSO |
299 | =head1 SEE ALSO |
266 | |
300 | |
267 | L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, |
301 | L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, |
268 | L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. |
302 | L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>, |
|
|
303 | L<Coro::Handle>, L<Coro::Socket>. |
269 | |
304 | |
270 | =head1 AUTHOR |
305 | =head1 AUTHOR |
271 | |
306 | |
272 | Marc Lehmann <pcg@goof.com> |
307 | Marc Lehmann <pcg@goof.com> |
273 | http://www.goof.com/pcg/marc/ |
308 | http://www.goof.com/pcg/marc/ |