| … | |
… | |
| 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 | |
|
|
23 | This module collection manages coroutines. Coroutines are similar to |
|
|
24 | threads but don't run in parallel. |
|
|
25 | |
|
|
26 | In this module, coroutines are defined as "callchain + lexical variables |
|
|
27 | + @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own |
|
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28 | callchain, it's own set of lexicals and it's own set of perl's most |
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29 | important global variables. |
|
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30 | |
| 23 | =cut |
31 | =cut |
| 24 | |
32 | |
| 25 | package Coro; |
33 | package Coro; |
| 26 | |
34 | |
|
|
35 | use strict; |
|
|
36 | no warnings "uninitialized"; |
|
|
37 | |
| 27 | use Coro::State; |
38 | use Coro::State; |
| 28 | |
39 | |
| 29 | use base Exporter; |
40 | use base Exporter::; |
| 30 | |
41 | |
| 31 | $VERSION = 0.04; |
42 | our $idle; # idle coroutine |
|
|
43 | our $main; # main coroutine |
|
|
44 | our $current; # current coroutine |
| 32 | |
45 | |
| 33 | @EXPORT = qw(async yield schedule); |
46 | our $VERSION = '2.5'; |
| 34 | @EXPORT_OK = qw($current); |
47 | |
|
|
48 | our @EXPORT = qw(async cede schedule terminate current); |
|
|
49 | our %EXPORT_TAGS = ( |
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50 | prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], |
|
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51 | ); |
|
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52 | our @EXPORT_OK = @{$EXPORT_TAGS{prio}}; |
| 35 | |
53 | |
| 36 | { |
54 | { |
| 37 | use subs 'async'; |
|
|
| 38 | |
|
|
| 39 | my @async; |
55 | my @async; |
|
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56 | my $init; |
| 40 | |
57 | |
| 41 | # this way of handling attributes simply is NOT scalable ;() |
58 | # this way of handling attributes simply is NOT scalable ;() |
| 42 | sub import { |
59 | sub import { |
|
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60 | no strict 'refs'; |
|
|
61 | |
| 43 | Coro->export_to_level(1, @_); |
62 | Coro->export_to_level(1, @_); |
|
|
63 | |
| 44 | my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
64 | my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
| 45 | *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
65 | *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
| 46 | my ($package, $ref) = (shift, shift); |
66 | my ($package, $ref) = (shift, shift); |
| 47 | my @attrs; |
67 | my @attrs; |
| 48 | for (@_) { |
68 | for (@_) { |
| 49 | if ($_ eq "Coro") { |
69 | if ($_ eq "Coro") { |
| 50 | push @async, $ref; |
70 | push @async, $ref; |
|
|
71 | unless ($init++) { |
|
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72 | eval q{ |
|
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73 | sub INIT { |
|
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74 | &async(pop @async) while @async; |
|
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75 | } |
|
|
76 | }; |
|
|
77 | } |
| 51 | } else { |
78 | } else { |
| 52 | push @attrs, @_; |
79 | push @attrs, $_; |
| 53 | } |
80 | } |
| 54 | } |
81 | } |
| 55 | return $old ? $old->($package, $name, @attrs) : @attrs; |
82 | return $old ? $old->($package, $ref, @attrs) : @attrs; |
| 56 | }; |
83 | }; |
| 57 | } |
84 | } |
| 58 | |
85 | |
| 59 | sub INIT { |
|
|
| 60 | async pop @async while @async; |
|
|
| 61 | } |
|
|
| 62 | } |
86 | } |
|
|
87 | |
|
|
88 | =over 4 |
| 63 | |
89 | |
| 64 | =item $main |
90 | =item $main |
| 65 | |
91 | |
| 66 | This coroutine represents the main program. |
92 | This coroutine represents the main program. |
| 67 | |
93 | |
| 68 | =cut |
94 | =cut |
| 69 | |
95 | |
| 70 | our $main = new Coro; |
96 | $main = new Coro; |
| 71 | |
97 | |
| 72 | =item $current |
98 | =item $current (or as function: current) |
| 73 | |
99 | |
| 74 | The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
100 | The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
| 75 | |
101 | |
| 76 | =cut |
102 | =cut |
| 77 | |
103 | |
| 78 | # maybe some other module used Coro::Specific before... |
104 | # maybe some other module used Coro::Specific before... |
| 79 | if ($current) { |
105 | if ($current) { |
| 80 | $main->{specific} = $current->{specific}; |
106 | $main->{specific} = $current->{specific}; |
| 81 | } |
107 | } |
| 82 | |
108 | |
| 83 | our $current = $main; |
109 | $current = $main; |
|
|
110 | |
|
|
111 | sub current() { $current } |
| 84 | |
112 | |
| 85 | =item $idle |
113 | =item $idle |
| 86 | |
114 | |
| 87 | The coroutine to switch to when no other coroutine is running. The default |
115 | The coroutine to switch to when no other coroutine is running. The default |
| 88 | implementation prints "FATAL: deadlock detected" and exits. |
116 | implementation prints "FATAL: deadlock detected" and exits. |
| 89 | |
117 | |
| 90 | =cut |
118 | =cut |
| 91 | |
119 | |
| 92 | # should be done using priorities :( |
120 | # should be done using priorities :( |
| 93 | our $idle = new Coro sub { |
121 | $idle = new Coro sub { |
| 94 | print STDERR "FATAL: deadlock detected\n"; |
122 | print STDERR "FATAL: deadlock detected\n"; |
| 95 | exit(51); |
123 | exit(51); |
| 96 | }; |
124 | }; |
| 97 | |
125 | |
| 98 | # we really need priorities... |
126 | # this coroutine is necessary because a coroutine |
| 99 | my @ready = (); # the ready queue. hehe, rather broken ;) |
127 | # cannot destroy itself. |
|
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128 | my @destroy; |
|
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129 | my $manager; |
|
|
130 | $manager = new Coro sub { |
|
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131 | while () { |
|
|
132 | # by overwriting the state object with the manager we destroy it |
|
|
133 | # while still being able to schedule this coroutine (in case it has |
|
|
134 | # been readied multiple times. this is harmless since the manager |
|
|
135 | # can be called as many times as neccessary and will always |
|
|
136 | # remove itself from the runqueue |
|
|
137 | while (@destroy) { |
|
|
138 | my $coro = pop @destroy; |
|
|
139 | $coro->{status} ||= []; |
|
|
140 | $_->ready for @{delete $coro->{join} || []}; |
|
|
141 | |
|
|
142 | # the next line destroys the _coro_state, but keeps the |
|
|
143 | # process itself intact (we basically make it a zombie |
|
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144 | # process that always runs the manager thread, so it's possible |
|
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145 | # to transfer() to this process). |
|
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146 | $coro->{_coro_state} = $manager->{_coro_state}; |
|
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147 | } |
|
|
148 | &schedule; |
|
|
149 | } |
|
|
150 | }; |
| 100 | |
151 | |
| 101 | # static methods. not really. |
152 | # static methods. not really. |
| 102 | |
153 | |
|
|
154 | =back |
|
|
155 | |
| 103 | =head2 STATIC METHODS |
156 | =head2 STATIC METHODS |
| 104 | |
157 | |
| 105 | Static methods are actually functions that operate on the current process only. |
158 | Static methods are actually functions that operate on the current process only. |
| 106 | |
159 | |
| 107 | =over 4 |
160 | =over 4 |
| 108 | |
161 | |
| 109 | =item async { ... }; |
162 | =item async { ... } [@args...] |
| 110 | |
163 | |
| 111 | Create a new asynchronous process and return it's process object |
164 | Create a new asynchronous process and return it's process object |
| 112 | (usually unused). When the sub returns the new process is automatically |
165 | (usually unused). When the sub returns the new process is automatically |
| 113 | terminated. |
166 | terminated. |
| 114 | |
167 | |
| 115 | =cut |
168 | When the coroutine dies, the program will exit, just as in the main |
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169 | program. |
| 116 | |
170 | |
|
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171 | # create a new coroutine that just prints its arguments |
|
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172 | async { |
|
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173 | print "@_\n"; |
|
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174 | } 1,2,3,4; |
|
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175 | |
|
|
176 | =cut |
|
|
177 | |
| 117 | sub async(&) { |
178 | sub async(&@) { |
| 118 | (new Coro $_[0])->ready; |
179 | my $pid = new Coro @_; |
|
|
180 | $manager->ready; # this ensures that the stack is cloned from the manager |
|
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181 | $pid->ready; |
|
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182 | $pid; |
| 119 | } |
183 | } |
| 120 | |
184 | |
| 121 | =item schedule |
185 | =item schedule |
| 122 | |
186 | |
| 123 | Calls the scheduler. Please note that the current process will not be put |
187 | Calls the scheduler. Please note that the current process will not be put |
| 124 | into the ready queue, so calling this function usually means you will |
188 | into the ready queue, so calling this function usually means you will |
| 125 | never be called again. |
189 | never be called again. |
| 126 | |
190 | |
| 127 | =cut |
191 | =cut |
| 128 | |
192 | |
| 129 | my $prev; |
|
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| 130 | |
|
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| 131 | sub schedule { |
|
|
| 132 | # should be done using priorities :( |
|
|
| 133 | ($prev, $current) = ($current, shift @ready || $idle); |
|
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| 134 | Coro::State::transfer($prev, $current); |
|
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| 135 | } |
|
|
| 136 | |
|
|
| 137 | =item yield |
193 | =item cede |
| 138 | |
194 | |
| 139 | Yield to other processes. This function puts the current process into the |
195 | "Cede" to other processes. This function puts the current process into the |
| 140 | ready queue and calls C<schedule>. |
196 | ready queue and calls C<schedule>, which has the effect of giving up the |
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197 | current "timeslice" to other coroutines of the same or higher priority. |
| 141 | |
198 | |
| 142 | =cut |
199 | =cut |
| 143 | |
200 | |
| 144 | sub yield { |
|
|
| 145 | $current->ready; |
|
|
| 146 | &schedule; |
|
|
| 147 | } |
|
|
| 148 | |
|
|
| 149 | =item terminate |
201 | =item terminate [arg...] |
| 150 | |
202 | |
| 151 | Terminates the current process. |
203 | Terminates the current process with the given status values (see L<cancel>). |
| 152 | |
204 | |
| 153 | =cut |
205 | =cut |
| 154 | |
206 | |
| 155 | sub terminate { |
207 | sub terminate { |
| 156 | &schedule; |
208 | $current->cancel (@_); |
| 157 | } |
209 | } |
| 158 | |
210 | |
| 159 | =back |
211 | =back |
| 160 | |
212 | |
| 161 | # dynamic methods |
213 | # dynamic methods |
| … | |
… | |
| 164 | |
216 | |
| 165 | These are the methods you can call on process objects. |
217 | These are the methods you can call on process objects. |
| 166 | |
218 | |
| 167 | =over 4 |
219 | =over 4 |
| 168 | |
220 | |
| 169 | =item new Coro \⊂ |
221 | =item new Coro \&sub [, @args...] |
| 170 | |
222 | |
| 171 | Create a new process and return it. When the sub returns the process |
223 | Create a new process and return it. When the sub returns the process |
| 172 | automatically terminates. To start the process you must first put it into |
224 | automatically terminates as if C<terminate> with the returned values were |
|
|
225 | called. To make the process run you must first put it into the ready queue |
| 173 | the ready queue by calling the ready method. |
226 | by calling the ready method. |
| 174 | |
227 | |
| 175 | =cut |
228 | =cut |
|
|
229 | |
|
|
230 | sub _newcoro { |
|
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231 | terminate &{+shift}; |
|
|
232 | } |
| 176 | |
233 | |
| 177 | sub new { |
234 | sub new { |
| 178 | my $class = shift; |
235 | my $class = shift; |
| 179 | my $proc = $_[0]; |
|
|
| 180 | bless { |
236 | bless { |
| 181 | _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), |
237 | _coro_state => (new Coro::State $_[0] && \&_newcoro, @_), |
| 182 | }, $class; |
238 | }, $class; |
| 183 | } |
239 | } |
| 184 | |
240 | |
| 185 | =item $process->ready |
241 | =item $process->ready |
| 186 | |
242 | |
| 187 | Put the current process into the ready queue. |
243 | Put the given process into the ready queue. |
| 188 | |
244 | |
| 189 | =cut |
245 | =cut |
| 190 | |
246 | |
| 191 | sub ready { |
247 | =item $process->cancel (arg...) |
| 192 | push @ready, $_[0]; |
248 | |
|
|
249 | Terminates the given process and makes it return the given arguments as |
|
|
250 | status (default: the empty list). |
|
|
251 | |
|
|
252 | =cut |
|
|
253 | |
|
|
254 | sub cancel { |
|
|
255 | my $self = shift; |
|
|
256 | $self->{status} = [@_]; |
|
|
257 | push @destroy, $self; |
|
|
258 | $manager->ready; |
|
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259 | &schedule if $current == $self; |
|
|
260 | } |
|
|
261 | |
|
|
262 | =item $process->join |
|
|
263 | |
|
|
264 | Wait until the coroutine terminates and return any values given to the |
|
|
265 | C<terminate> or C<cancel> functions. C<join> can be called multiple times |
|
|
266 | from multiple processes. |
|
|
267 | |
|
|
268 | =cut |
|
|
269 | |
|
|
270 | sub join { |
|
|
271 | my $self = shift; |
|
|
272 | unless ($self->{status}) { |
|
|
273 | push @{$self->{join}}, $current; |
|
|
274 | &schedule; |
|
|
275 | } |
|
|
276 | wantarray ? @{$self->{status}} : $self->{status}[0]; |
|
|
277 | } |
|
|
278 | |
|
|
279 | =item $oldprio = $process->prio($newprio) |
|
|
280 | |
|
|
281 | Sets (or gets, if the argument is missing) the priority of the |
|
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282 | process. Higher priority processes get run before lower priority |
|
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283 | processes. Priorities are small signed integers (currently -4 .. +3), |
|
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284 | that you can refer to using PRIO_xxx constants (use the import tag :prio |
|
|
285 | to get then): |
|
|
286 | |
|
|
287 | PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
|
|
288 | 3 > 1 > 0 > -1 > -3 > -4 |
|
|
289 | |
|
|
290 | # set priority to HIGH |
|
|
291 | current->prio(PRIO_HIGH); |
|
|
292 | |
|
|
293 | The idle coroutine ($Coro::idle) always has a lower priority than any |
|
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294 | existing coroutine. |
|
|
295 | |
|
|
296 | Changing the priority of the current process will take effect immediately, |
|
|
297 | but changing the priority of processes in the ready queue (but not |
|
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298 | running) will only take effect after the next schedule (of that |
|
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299 | process). This is a bug that will be fixed in some future version. |
|
|
300 | |
|
|
301 | =cut |
|
|
302 | |
|
|
303 | sub prio { |
|
|
304 | my $old = $_[0]{prio}; |
|
|
305 | $_[0]{prio} = $_[1] if @_ > 1; |
|
|
306 | $old; |
|
|
307 | } |
|
|
308 | |
|
|
309 | =item $newprio = $process->nice($change) |
|
|
310 | |
|
|
311 | Similar to C<prio>, but subtract the given value from the priority (i.e. |
|
|
312 | higher values mean lower priority, just as in unix). |
|
|
313 | |
|
|
314 | =cut |
|
|
315 | |
|
|
316 | sub nice { |
|
|
317 | $_[0]{prio} -= $_[1]; |
|
|
318 | } |
|
|
319 | |
|
|
320 | =item $olddesc = $process->desc($newdesc) |
|
|
321 | |
|
|
322 | Sets (or gets in case the argument is missing) the description for this |
|
|
323 | process. This is just a free-form string you can associate with a process. |
|
|
324 | |
|
|
325 | =cut |
|
|
326 | |
|
|
327 | sub desc { |
|
|
328 | my $old = $_[0]{desc}; |
|
|
329 | $_[0]{desc} = $_[1] if @_ > 1; |
|
|
330 | $old; |
| 193 | } |
331 | } |
| 194 | |
332 | |
| 195 | =back |
333 | =back |
| 196 | |
334 | |
| 197 | =cut |
335 | =cut |
| 198 | |
336 | |
| 199 | 1; |
337 | 1; |
| 200 | |
338 | |
|
|
339 | =head1 BUGS/LIMITATIONS |
|
|
340 | |
|
|
341 | - you must make very sure that no coro is still active on global |
|
|
342 | destruction. very bad things might happen otherwise (usually segfaults). |
|
|
343 | |
|
|
344 | - this module is not thread-safe. You should only ever use this module |
|
|
345 | from the same thread (this requirement might be losened in the future |
|
|
346 | to allow per-thread schedulers, but Coro::State does not yet allow |
|
|
347 | this). |
|
|
348 | |
| 201 | =head1 SEE ALSO |
349 | =head1 SEE ALSO |
| 202 | |
350 | |
| 203 | L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, |
351 | Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>. |
| 204 | L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. |
352 | |
|
|
353 | Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>. |
|
|
354 | |
|
|
355 | Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>. |
|
|
356 | |
|
|
357 | Embedding: L<Coro:MakeMaker> |
| 205 | |
358 | |
| 206 | =head1 AUTHOR |
359 | =head1 AUTHOR |
| 207 | |
360 | |
| 208 | Marc Lehmann <pcg@goof.com> |
361 | Marc Lehmann <schmorp@schmorp.de> |
| 209 | http://www.goof.com/pcg/marc/ |
362 | http://home.schmorp.de/ |
| 210 | |
363 | |
| 211 | =cut |
364 | =cut |
| 212 | |
365 | |
