| … | |
… | |
| 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. |
|
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25 | |
|
|
26 | In this module, coroutines are defined as "callchain + lexical variables |
|
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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; |
|
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36 | no warnings "uninitialized"; |
|
|
37 | |
| 27 | use Coro::State; |
38 | use Coro::State; |
| 28 | |
39 | |
| 29 | use base Exporter; |
40 | use base qw(Coro::State Exporter); |
| 30 | |
41 | |
| 31 | $VERSION = 0.03; |
42 | our $idle; # idle handler |
|
|
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); |
|
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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'; |
|
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| 38 | |
|
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| 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 | } |
| 63 | |
87 | |
| 64 | my $idle = new Coro sub { |
88 | =over 4 |
| 65 | &yield while 1; |
|
|
| 66 | }; |
|
|
| 67 | |
89 | |
| 68 | =item $main |
90 | =item $main |
| 69 | |
91 | |
| 70 | This coroutine represents the main program. |
92 | This coroutine represents the main program. |
| 71 | |
93 | |
| 72 | =cut |
94 | =cut |
| 73 | |
95 | |
| 74 | $main = new Coro; |
96 | $main = new Coro; |
| 75 | |
97 | |
| 76 | =item $current |
98 | =item $current (or as function: current) |
| 77 | |
99 | |
| 78 | The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
100 | The current coroutine (the last coroutine switched to). The initial value |
|
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101 | is C<$main> (of course). |
|
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102 | |
|
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103 | This variable is B<strictly> I<read-only>. It is provided for performance |
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104 | reasons. If performance is not essentiel you are encouraged to use the |
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105 | C<Coro::current> function instead. |
| 79 | |
106 | |
| 80 | =cut |
107 | =cut |
| 81 | |
108 | |
| 82 | # maybe some other module used Coro::Specific before... |
109 | # maybe some other module used Coro::Specific before... |
| 83 | if ($current) { |
110 | if ($current) { |
| 84 | $main->{specific} = $current->{specific}; |
111 | $main->{specific} = $current->{specific}; |
| 85 | } |
112 | } |
| 86 | |
113 | |
| 87 | $current = $main; |
114 | $current = $main; |
| 88 | |
115 | |
| 89 | # we really need priorities... |
116 | sub current() { $current } |
| 90 | my @ready = (); # the ready queue. hehe, rather broken ;) |
117 | |
|
|
118 | =item $idle |
|
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119 | |
|
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120 | A callback that is called whenever the scheduler finds no ready coroutines |
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121 | to run. The default implementation prints "FATAL: deadlock detected" and |
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122 | exits. |
|
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123 | |
|
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124 | This hook is overwritten by modules such as C<Coro::Timer> and |
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125 | C<Coro::Event> to wait on an external event that hopefully wakes up some |
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126 | coroutine. |
|
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127 | |
|
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128 | =cut |
|
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129 | |
|
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130 | $idle = sub { |
|
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131 | print STDERR "FATAL: deadlock detected\n"; |
|
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132 | exit (51); |
|
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133 | }; |
|
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134 | |
|
|
135 | # this coroutine is necessary because a coroutine |
|
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136 | # cannot destroy itself. |
|
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137 | my @destroy; |
|
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138 | my $manager; |
|
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139 | $manager = new Coro sub { |
|
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140 | while () { |
|
|
141 | # by overwriting the state object with the manager we destroy it |
|
|
142 | # while still being able to schedule this coroutine (in case it has |
|
|
143 | # been readied multiple times. this is harmless since the manager |
|
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144 | # can be called as many times as neccessary and will always |
|
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145 | # remove itself from the runqueue |
|
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146 | while (@destroy) { |
|
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147 | my $coro = pop @destroy; |
|
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148 | $coro->{status} ||= []; |
|
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149 | $_->ready for @{delete $coro->{join} || []}; |
|
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150 | |
|
|
151 | # the next line destroys the coro state, but keeps the |
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152 | # process itself intact (we basically make it a zombie |
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153 | # process that always runs the manager thread, so it's possible |
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154 | # to transfer() to this process). |
|
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155 | $coro->_clone_state_from ($manager); |
|
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156 | } |
|
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157 | &schedule; |
|
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158 | } |
|
|
159 | }; |
| 91 | |
160 | |
| 92 | # static methods. not really. |
161 | # static methods. not really. |
| 93 | |
162 | |
|
|
163 | =back |
|
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164 | |
| 94 | =head2 STATIC METHODS |
165 | =head2 STATIC METHODS |
| 95 | |
166 | |
| 96 | Static methods are actually functions that operate on the current process only. |
167 | Static methods are actually functions that operate on the current process only. |
| 97 | |
168 | |
| 98 | =over 4 |
169 | =over 4 |
| 99 | |
170 | |
| 100 | =item async { ... }; |
171 | =item async { ... } [@args...] |
| 101 | |
172 | |
| 102 | Create a new asynchronous process and return it's process object |
173 | Create a new asynchronous process and return it's process object |
| 103 | (usually unused). When the sub returns the new process is automatically |
174 | (usually unused). When the sub returns the new process is automatically |
| 104 | terminated. |
175 | terminated. |
| 105 | |
176 | |
| 106 | =cut |
177 | When the coroutine dies, the program will exit, just as in the main |
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178 | program. |
| 107 | |
179 | |
|
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180 | # create a new coroutine that just prints its arguments |
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181 | async { |
|
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182 | print "@_\n"; |
|
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183 | } 1,2,3,4; |
|
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184 | |
|
|
185 | =cut |
|
|
186 | |
| 108 | sub async(&) { |
187 | sub async(&@) { |
| 109 | (new Coro $_[0])->ready; |
188 | my $pid = new Coro @_; |
|
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189 | $manager->ready; # this ensures that the stack is cloned from the manager |
|
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190 | $pid->ready; |
|
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191 | $pid; |
| 110 | } |
192 | } |
| 111 | |
193 | |
| 112 | =item schedule |
194 | =item schedule |
| 113 | |
195 | |
| 114 | Calls the scheduler. Please note that the current process will not be put |
196 | Calls the scheduler. Please note that the current process will not be put |
| 115 | into the ready queue, so calling this function usually means you will |
197 | into the ready queue, so calling this function usually means you will |
| 116 | never be called again. |
198 | never be called again. |
| 117 | |
199 | |
| 118 | =cut |
200 | =cut |
| 119 | |
201 | |
| 120 | my $prev; |
|
|
| 121 | |
|
|
| 122 | sub schedule { |
|
|
| 123 | ($prev, $current) = ($current, shift @ready); |
|
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| 124 | Coro::State::transfer($prev, $current); |
|
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| 125 | } |
|
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| 126 | |
|
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| 127 | =item yield |
202 | =item cede |
| 128 | |
203 | |
| 129 | Yield to other processes. This function puts the current process into the |
204 | "Cede" to other processes. This function puts the current process into the |
| 130 | ready queue and calls C<schedule>. |
205 | ready queue and calls C<schedule>, which has the effect of giving up the |
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206 | current "timeslice" to other coroutines of the same or higher priority. |
| 131 | |
207 | |
| 132 | =cut |
208 | =cut |
| 133 | |
209 | |
| 134 | sub yield { |
|
|
| 135 | $current->ready; |
|
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| 136 | &schedule; |
|
|
| 137 | } |
|
|
| 138 | |
|
|
| 139 | =item terminate |
210 | =item terminate [arg...] |
| 140 | |
211 | |
| 141 | Terminates the current process. |
212 | Terminates the current process with the given status values (see L<cancel>). |
| 142 | |
213 | |
| 143 | =cut |
214 | =cut |
| 144 | |
215 | |
| 145 | sub terminate { |
216 | sub terminate { |
| 146 | &schedule; |
217 | $current->cancel (@_); |
| 147 | } |
218 | } |
| 148 | |
219 | |
| 149 | =back |
220 | =back |
| 150 | |
221 | |
| 151 | # dynamic methods |
222 | # dynamic methods |
| … | |
… | |
| 154 | |
225 | |
| 155 | These are the methods you can call on process objects. |
226 | These are the methods you can call on process objects. |
| 156 | |
227 | |
| 157 | =over 4 |
228 | =over 4 |
| 158 | |
229 | |
| 159 | =item new Coro \⊂ |
230 | =item new Coro \&sub [, @args...] |
| 160 | |
231 | |
| 161 | Create a new process and return it. When the sub returns the process |
232 | Create a new process and return it. When the sub returns the process |
| 162 | automatically terminates. To start the process you must first put it into |
233 | automatically terminates as if C<terminate> with the returned values were |
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234 | called. To make the process run you must first put it into the ready queue |
| 163 | the ready queue by calling the ready method. |
235 | by calling the ready method. |
| 164 | |
236 | |
| 165 | =cut |
237 | =cut |
|
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238 | |
|
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239 | sub _new_coro { |
|
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240 | # $current->_clear_idle_sp; # set the idle sp on the following cede |
|
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241 | _set_cede_self; # ensures that cede cede's us first |
|
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242 | cede; |
|
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243 | terminate &{+shift}; |
|
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244 | } |
| 166 | |
245 | |
| 167 | sub new { |
246 | sub new { |
| 168 | my $class = shift; |
247 | my $class = shift; |
| 169 | my $proc = $_[0]; |
248 | |
| 170 | bless { |
249 | $class->SUPER::new (\&_new_coro, @_) |
| 171 | _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), |
|
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| 172 | }, $class; |
|
|
| 173 | } |
250 | } |
| 174 | |
251 | |
| 175 | =item $process->ready |
252 | =item $process->ready |
| 176 | |
253 | |
| 177 | Put the current process into the ready queue. |
254 | Put the given process into the ready queue. |
| 178 | |
255 | |
| 179 | =cut |
256 | =cut |
| 180 | |
257 | |
| 181 | sub ready { |
258 | =item $process->cancel (arg...) |
| 182 | push @ready, $_[0]; |
259 | |
|
|
260 | Terminates the given process and makes it return the given arguments as |
|
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261 | status (default: the empty list). |
|
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262 | |
|
|
263 | =cut |
|
|
264 | |
|
|
265 | sub cancel { |
|
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266 | my $self = shift; |
|
|
267 | $self->{status} = [@_]; |
|
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268 | push @destroy, $self; |
|
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269 | $manager->ready; |
|
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270 | &schedule if $current == $self; |
|
|
271 | } |
|
|
272 | |
|
|
273 | =item $process->join |
|
|
274 | |
|
|
275 | Wait until the coroutine terminates and return any values given to the |
|
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276 | C<terminate> or C<cancel> functions. C<join> can be called multiple times |
|
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277 | from multiple processes. |
|
|
278 | |
|
|
279 | =cut |
|
|
280 | |
|
|
281 | sub join { |
|
|
282 | my $self = shift; |
|
|
283 | unless ($self->{status}) { |
|
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284 | push @{$self->{join}}, $current; |
|
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285 | &schedule; |
|
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286 | } |
|
|
287 | wantarray ? @{$self->{status}} : $self->{status}[0]; |
|
|
288 | } |
|
|
289 | |
|
|
290 | =item $oldprio = $process->prio ($newprio) |
|
|
291 | |
|
|
292 | Sets (or gets, if the argument is missing) the priority of the |
|
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293 | process. Higher priority processes get run before lower priority |
|
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294 | processes. Priorities are small signed integers (currently -4 .. +3), |
|
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295 | that you can refer to using PRIO_xxx constants (use the import tag :prio |
|
|
296 | to get then): |
|
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297 | |
|
|
298 | PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
|
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299 | 3 > 1 > 0 > -1 > -3 > -4 |
|
|
300 | |
|
|
301 | # set priority to HIGH |
|
|
302 | current->prio(PRIO_HIGH); |
|
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303 | |
|
|
304 | The idle coroutine ($Coro::idle) always has a lower priority than any |
|
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305 | existing coroutine. |
|
|
306 | |
|
|
307 | Changing the priority of the current process will take effect immediately, |
|
|
308 | but changing the priority of processes in the ready queue (but not |
|
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309 | running) will only take effect after the next schedule (of that |
|
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310 | process). This is a bug that will be fixed in some future version. |
|
|
311 | |
|
|
312 | =item $newprio = $process->nice ($change) |
|
|
313 | |
|
|
314 | Similar to C<prio>, but subtract the given value from the priority (i.e. |
|
|
315 | higher values mean lower priority, just as in unix). |
|
|
316 | |
|
|
317 | =item $olddesc = $process->desc ($newdesc) |
|
|
318 | |
|
|
319 | Sets (or gets in case the argument is missing) the description for this |
|
|
320 | process. This is just a free-form string you can associate with a process. |
|
|
321 | |
|
|
322 | =cut |
|
|
323 | |
|
|
324 | sub desc { |
|
|
325 | my $old = $_[0]{desc}; |
|
|
326 | $_[0]{desc} = $_[1] if @_ > 1; |
|
|
327 | $old; |
| 183 | } |
328 | } |
| 184 | |
329 | |
| 185 | =back |
330 | =back |
| 186 | |
331 | |
| 187 | =cut |
332 | =cut |
| 188 | |
333 | |
| 189 | 1; |
334 | 1; |
| 190 | |
335 | |
|
|
336 | =head1 BUGS/LIMITATIONS |
|
|
337 | |
|
|
338 | - you must make very sure that no coro is still active on global |
|
|
339 | destruction. very bad things might happen otherwise (usually segfaults). |
|
|
340 | |
|
|
341 | - this module is not thread-safe. You should only ever use this module |
|
|
342 | from the same thread (this requirement might be losened in the future |
|
|
343 | to allow per-thread schedulers, but Coro::State does not yet allow |
|
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344 | this). |
|
|
345 | |
|
|
346 | =head1 SEE ALSO |
|
|
347 | |
|
|
348 | Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>. |
|
|
349 | |
|
|
350 | Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>. |
|
|
351 | |
|
|
352 | Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>. |
|
|
353 | |
|
|
354 | Embedding: L<Coro:MakeMaker> |
|
|
355 | |
| 191 | =head1 AUTHOR |
356 | =head1 AUTHOR |
| 192 | |
357 | |
| 193 | Marc Lehmann <pcg@goof.com> |
358 | Marc Lehmann <schmorp@schmorp.de> |
| 194 | http://www.goof.com/pcg/marc/ |
359 | http://home.schmorp.de/ |
| 195 | |
360 | |
| 196 | =cut |
361 | =cut |
| 197 | |
362 | |
