1 | =head1 NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | AnyEvent::ProcessPool - manage pools of perl worker processes, exec'ed or fork'ed |
3 | AnyEvent::Fork - everything you wanted to use fork() for, but couldn't |
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4 | |
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5 | ATTENTION, this is a very early release, and very untested. Consider it a |
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6 | technology preview. |
4 | |
7 | |
5 | =head1 SYNOPSIS |
8 | =head1 SYNOPSIS |
6 | |
9 | |
7 | use AnyEvent::ProcessPool; |
10 | use AnyEvent::Fork; |
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11 | |
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12 | ################################################################## |
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13 | # create a single new process, tell it to run your worker function |
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14 | |
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15 | AnyEvent::Fork |
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16 | ->new |
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17 | ->require ("MyModule") |
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18 | ->run ("MyModule::worker, sub { |
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19 | my ($master_filehandle) = @_; |
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20 | |
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21 | # now $master_filehandle is connected to the |
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22 | # $slave_filehandle in the new process. |
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23 | }); |
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24 | |
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25 | # MyModule::worker might look like this |
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26 | sub MyModule::worker { |
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27 | my ($slave_filehandle) = @_; |
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28 | |
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29 | # now $slave_filehandle is connected to the $master_filehandle |
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30 | # in the original prorcess. have fun! |
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31 | } |
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32 | |
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33 | ################################################################## |
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34 | # create a pool of server processes all accepting on the same socket |
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35 | |
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36 | # create listener socket |
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37 | my $listener = ...; |
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38 | |
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39 | # create a pool template, initialise it and give it the socket |
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40 | my $pool = AnyEvent::Fork |
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41 | ->new |
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42 | ->require ("Some::Stuff", "My::Server") |
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43 | ->send_fh ($listener); |
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44 | |
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45 | # now create 10 identical workers |
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46 | for my $id (1..10) { |
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47 | $pool |
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48 | ->fork |
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49 | ->send_arg ($id) |
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50 | ->run ("My::Server::run"); |
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51 | } |
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52 | |
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53 | # now do other things - maybe use the filehandle provided by run |
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54 | # to wait for the processes to die. or whatever. |
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55 | |
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56 | # My::Server::run might look like this |
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57 | sub My::Server::run { |
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58 | my ($slave, $listener, $id) = @_; |
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59 | |
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60 | close $slave; # we do not use the socket, so close it to save resources |
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61 | |
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62 | # we could go ballistic and use e.g. AnyEvent here, or IO::AIO, |
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63 | # or anything we usually couldn't do in a process forked normally. |
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64 | while (my $socket = $listener->accept) { |
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65 | # do sth. with new socket |
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66 | } |
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67 | } |
8 | |
68 | |
9 | =head1 DESCRIPTION |
69 | =head1 DESCRIPTION |
10 | |
70 | |
11 | This module allows you to create single worker processes but also worker |
71 | This module allows you to create new processes, without actually forking |
12 | pool that share memory, by forking from the main program, or exec'ing new |
72 | them from your current process (avoiding the problems of forking), but |
13 | perl interpreters from a module. |
73 | preserving most of the advantages of fork. |
14 | |
74 | |
15 | You create a new processes in a pool by specifying a function to call |
75 | It can be used to create new worker processes or new independent |
16 | with any combination of string values and file handles. |
76 | subprocesses for short- and long-running jobs, process pools (e.g. for use |
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77 | in pre-forked servers) but also to spawn new external processes (such as |
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78 | CGI scripts from a webserver), which can be faster (and more well behaved) |
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79 | than using fork+exec in big processes. |
17 | |
80 | |
18 | A pool can have initialisation code which is executed before forking. The |
81 | Special care has been taken to make this module useful from other modules, |
19 | initialisation code is only executed once and the resulting process is |
82 | while still supporting specialised environments such as L<App::Staticperl> |
20 | cached, to be used as a template. |
83 | or L<PAR::Packer>. |
21 | |
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22 | Pools without such initialisation code don't cache an extra process. |
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23 | |
84 | |
24 | =head1 PROBLEM STATEMENT |
85 | =head1 PROBLEM STATEMENT |
25 | |
86 | |
26 | There are two ways to implement parallel processing on UNIX like operating |
87 | There are two ways to implement parallel processing on UNIX like operating |
27 | systems - fork and process, and fork+exec and process. They have different |
88 | systems - fork and process, and fork+exec and process. They have different |
… | |
… | |
110 | time, and the memory is not shared with anything else. |
171 | time, and the memory is not shared with anything else. |
111 | |
172 | |
112 | This is ideal for when you only need one extra process of a kind, with the |
173 | This is ideal for when you only need one extra process of a kind, with the |
113 | option of starting and stipping it on demand. |
174 | option of starting and stipping it on demand. |
114 | |
175 | |
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176 | Example: |
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177 | |
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178 | AnyEvent::Fork |
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179 | ->new |
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180 | ->require ("Some::Module") |
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181 | ->run ("Some::Module::run", sub { |
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182 | my ($fork_fh) = @_; |
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183 | }); |
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184 | |
115 | =item fork a new template process, load code, then fork processes off of |
185 | =item fork a new template process, load code, then fork processes off of |
116 | it and run the code |
186 | it and run the code |
117 | |
187 | |
118 | When you need to have a bunch of processes that all execute the same (or |
188 | When you need to have a bunch of processes that all execute the same (or |
119 | very similar) tasks, then a good way is to create a new template process |
189 | very similar) tasks, then a good way is to create a new template process |
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127 | The disadvantage of this approach is that you need to create a template |
197 | The disadvantage of this approach is that you need to create a template |
128 | process for the sole purpose of forking new processes from it, but if you |
198 | process for the sole purpose of forking new processes from it, but if you |
129 | only need a fixed number of proceses you can create them, and then destroy |
199 | only need a fixed number of proceses you can create them, and then destroy |
130 | the template process. |
200 | the template process. |
131 | |
201 | |
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202 | Example: |
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203 | |
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204 | my $template = AnyEvent::Fork->new->require ("Some::Module"); |
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205 | |
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206 | for (1..10) { |
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207 | $template->fork->run ("Some::Module::run", sub { |
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208 | my ($fork_fh) = @_; |
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209 | }); |
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210 | } |
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211 | |
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212 | # at this point, you can keep $template around to fork new processes |
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213 | # later, or you can destroy it, which causes it to vanish. |
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214 | |
132 | =item execute a new perl interpreter, load some code, run it |
215 | =item execute a new perl interpreter, load some code, run it |
133 | |
216 | |
134 | This is relatively slow, and doesn't allow you to share memory between |
217 | This is relatively slow, and doesn't allow you to share memory between |
135 | multiple processes. |
218 | multiple processes. |
136 | |
219 | |
137 | The only advantage is that you don't have to have a template process |
220 | The only advantage is that you don't have to have a template process |
138 | hanging around all the time to fork off some new processes, which might be |
221 | hanging around all the time to fork off some new processes, which might be |
139 | an advantage when there are long time spans where no extra processes are |
222 | an advantage when there are long time spans where no extra processes are |
140 | needed. |
223 | needed. |
141 | |
224 | |
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225 | Example: |
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226 | |
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227 | AnyEvent::Fork |
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228 | ->new_exec |
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229 | ->require ("Some::Module") |
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230 | ->run ("Some::Module::run", sub { |
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231 | my ($fork_fh) = @_; |
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232 | }); |
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233 | |
142 | =back |
234 | =back |
143 | |
235 | |
144 | =head1 FUNCTIONS |
236 | =head1 FUNCTIONS |
145 | |
237 | |
146 | =over 4 |
238 | =over 4 |
147 | |
239 | |
148 | =cut |
240 | =cut |
149 | |
241 | |
150 | package AnyEvent::ProcessPool; |
242 | package AnyEvent::Fork; |
151 | |
243 | |
152 | use common::sense; |
244 | use common::sense; |
153 | |
245 | |
154 | use Socket (); |
246 | use Socket (); |
155 | |
247 | |
156 | use Proc::FastSpawn; |
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157 | use AnyEvent; |
248 | use AnyEvent; |
158 | use AnyEvent::ProcessPool::Util; |
249 | use AnyEvent::Fork::Util; |
159 | use AnyEvent::Util (); |
250 | use AnyEvent::Util (); |
160 | |
251 | |
161 | BEGIN { |
252 | our $PERL; # the path to the perl interpreter, deduces with various forms of magic |
162 | # require Exporter; |
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163 | } |
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164 | |
253 | |
165 | =item my $pool = new AnyEvent::ProcessPool key => value... |
254 | =item my $pool = new AnyEvent::Fork key => value... |
166 | |
255 | |
167 | Create a new process pool. The following named parameters are supported: |
256 | Create a new process pool. The following named parameters are supported: |
168 | |
257 | |
169 | =over 4 |
258 | =over 4 |
170 | |
259 | |
171 | =back |
260 | =back |
172 | |
261 | |
173 | =cut |
262 | =cut |
174 | |
263 | |
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264 | # the early fork template process |
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265 | our $EARLY; |
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266 | |
175 | # the template process |
267 | # the empty template process |
176 | our $template; |
268 | our $TEMPLATE; |
177 | |
269 | |
178 | sub _queue { |
270 | sub _cmd { |
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271 | my $self = shift; |
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272 | |
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273 | #TODO: maybe append the packet to any existing string command already in the queue |
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274 | |
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275 | # ideally, we would want to use "a (w/a)*" as format string, but perl versions |
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276 | # from at least 5.8.9 to 5.16.3 are all buggy and can't unpack it. |
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277 | push @{ $self->[2] }, pack "N/a", pack "(w/a)*", @_; |
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278 | |
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279 | $self->[3] ||= AE::io $self->[1], 1, sub { |
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280 | # send the next "thing" in the queue - either a reference to an fh, |
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281 | # or a plain string. |
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282 | |
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283 | if (ref $self->[2][0]) { |
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284 | # send fh |
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285 | AnyEvent::Fork::Util::fd_send fileno $self->[1], fileno ${ $self->[2][0] } |
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286 | and shift @{ $self->[2] }; |
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287 | |
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288 | } else { |
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289 | # send string |
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290 | my $len = syswrite $self->[1], $self->[2][0] |
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291 | or do { undef $self->[3]; die "AnyEvent::Fork: command write failure: $!" }; |
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292 | |
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293 | substr $self->[2][0], 0, $len, ""; |
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294 | shift @{ $self->[2] } unless length $self->[2][0]; |
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295 | } |
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296 | |
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297 | unless (@{ $self->[2] }) { |
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298 | undef $self->[3]; |
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299 | # invoke run callback |
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300 | $self->[0]->($self->[1]) if $self->[0]; |
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301 | } |
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302 | }; |
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303 | } |
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304 | |
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305 | sub _new { |
179 | my ($pid, $fh) = @_; |
306 | my ($self, $fh) = @_; |
180 | |
307 | |
181 | [ |
308 | AnyEvent::Util::fh_nonblocking $fh, 1; |
182 | $pid, |
309 | |
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310 | $self = bless [ |
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311 | undef, # run callback |
183 | $fh, |
312 | $fh, |
184 | [], |
313 | [], # write queue - strings or fd's |
185 | undef |
314 | undef, # AE watcher |
186 | ] |
315 | ], $self; |
187 | } |
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188 | |
316 | |
189 | sub queue_cmd { |
317 | $self |
190 | my $queue = shift; |
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191 | |
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192 | push @{ $queue->[2] }, pack "N/a", pack "a (w/a)*", @_; |
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193 | |
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194 | $queue->[3] ||= AE::io $queue->[1], 1, sub { |
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195 | if (ref $queue->[2][0]) { |
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196 | AnyEvent::ProcessPool::Util::fd_send fileno $queue->[1], fileno ${ $queue->[2][0] } |
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197 | and shift @{ $queue->[2] }; |
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198 | } else { |
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199 | my $len = syswrite $queue->[1], $queue->[2][0] |
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200 | or do { undef $queue->[3]; die "AnyEvent::ProcessPool::queue write failure: $!" }; |
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201 | substr $queue->[2][0], 0, $len, ""; |
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202 | shift @{ $queue->[2] } unless length $queue->[2][0]; |
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203 | } |
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204 | |
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205 | undef $queue->[3] unless @{ $queue->[2] }; |
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206 | }; |
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207 | } |
318 | } |
208 | |
319 | |
209 | sub run_template { |
320 | # fork template from current process, used by AnyEvent::Fork::Early/Template |
210 | return if $template; |
321 | sub _new_fork { |
211 | |
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212 | my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
322 | my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
213 | AnyEvent::Util::fh_nonblocking $fh, 1; |
323 | my $parent = $$; |
214 | fd_inherit fileno $slave; |
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215 | |
324 | |
216 | my %env = %ENV; |
325 | my $pid = fork; |
217 | $env{PERL5LIB} = join ":", grep !ref, @INC; |
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218 | |
326 | |
219 | my $pid = spawn |
327 | if ($pid eq 0) { |
220 | $^X, |
328 | require AnyEvent::Fork::Serve; |
221 | ["perl", "-MAnyEvent::ProcessPool::Serve", "-e", "AnyEvent::ProcessPool::Serve::me", fileno $slave], |
329 | $AnyEvent::Fork::Serve::OWNER = $parent; |
222 | [map "$_=$env{$_}", keys %env], |
330 | close $fh; |
223 | or die "unable to spawn AnyEvent::ProcessPool server: $!"; |
331 | $0 = "$_[1] of $parent"; |
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332 | AnyEvent::Fork::Serve::serve ($slave); |
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333 | AnyEvent::Fork::Util::_exit 0; |
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334 | } elsif (!$pid) { |
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335 | die "AnyEvent::Fork::Early/Template: unable to fork template process: $!"; |
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336 | } |
224 | |
337 | |
225 | close $slave; |
338 | AnyEvent::Fork->_new ($fh) |
226 | |
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227 | $template = _queue $pid, $fh; |
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228 | |
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229 | my ($a, $b) = AnyEvent::Util::portable_socketpair; |
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230 | |
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231 | queue_cmd $template, "Iabc"; |
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232 | push @{ $template->[2] }, \$b; |
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233 | |
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234 | use Coro::AnyEvent; Coro::AnyEvent::sleep 1; |
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235 | undef $b; |
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236 | die "x" . <$a>; |
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237 | } |
339 | } |
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340 | |
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341 | =item my $proc = new AnyEvent::Fork |
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342 | |
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343 | Create a new "empty" perl interpreter process and returns its process |
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344 | object for further manipulation. |
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345 | |
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346 | The new process is forked from a template process that is kept around |
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347 | for this purpose. When it doesn't exist yet, it is created by a call to |
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348 | C<new_exec> and kept around for future calls. |
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349 | |
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350 | When the process object is destroyed, it will release the file handle |
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351 | that connects it with the new process. When the new process has not yet |
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352 | called C<run>, then the process will exit. Otherwise, what happens depends |
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353 | entirely on the code that is executed. |
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354 | |
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355 | =cut |
238 | |
356 | |
239 | sub new { |
357 | sub new { |
240 | my $class = shift; |
358 | my $class = shift; |
241 | |
359 | |
242 | my $self = bless { |
360 | $TEMPLATE ||= $class->new_exec; |
243 | @_ |
361 | $TEMPLATE->fork |
244 | }, $class; |
362 | } |
245 | |
363 | |
246 | run_template; |
364 | =item $new_proc = $proc->fork |
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365 | |
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366 | Forks C<$proc>, creating a new process, and returns the process object |
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367 | of the new process. |
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368 | |
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369 | If any of the C<send_> functions have been called before fork, then they |
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370 | will be cloned in the child. For example, in a pre-forked server, you |
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371 | might C<send_fh> the listening socket into the template process, and then |
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372 | keep calling C<fork> and C<run>. |
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373 | |
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374 | =cut |
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375 | |
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376 | sub fork { |
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377 | my ($self) = @_; |
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378 | |
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379 | my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
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380 | |
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381 | $self->send_fh ($slave); |
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382 | $self->_cmd ("f"); |
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383 | |
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384 | AnyEvent::Fork->_new ($fh) |
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385 | } |
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386 | |
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387 | =item my $proc = new_exec AnyEvent::Fork |
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388 | |
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389 | Create a new "empty" perl interpreter process and returns its process |
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390 | object for further manipulation. |
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391 | |
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392 | Unlike the C<new> method, this method I<always> spawns a new perl process |
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393 | (except in some cases, see L<AnyEvent::Fork::Early> for details). This |
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394 | reduces the amount of memory sharing that is possible, and is also slower. |
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395 | |
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396 | You should use C<new> whenever possible, except when having a template |
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397 | process around is unacceptable. |
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398 | |
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399 | The path to the perl interpreter is divined usign various methods - first |
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400 | C<$^X> is investigated to see if the path ends with something that sounds |
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401 | as if it were the perl interpreter. Failing this, the module falls back to |
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402 | using C<$Config::Config{perlpath}>. |
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403 | |
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404 | =cut |
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405 | |
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406 | sub new_exec { |
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407 | my ($self) = @_; |
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408 | |
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409 | return $EARLY->fork |
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410 | if $EARLY; |
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411 | |
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412 | # first find path of perl |
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413 | my $perl = $; |
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414 | |
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415 | # first we try $^X, but the path must be absolute (always on win32), and end in sth. |
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416 | # that looks like perl. this obviously only works for posix and win32 |
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417 | unless ( |
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418 | (AnyEvent::Fork::Util::WIN32 || $perl =~ m%^/%) |
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419 | && $perl =~ m%[/\\]perl(?:[0-9]+(\.[0-9]+)+)?(\.exe)?$%i |
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420 | ) { |
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421 | # if it doesn't look perlish enough, try Config |
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422 | require Config; |
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423 | $perl = $Config::Config{perlpath}; |
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424 | $perl =~ s/(?:\Q$Config::Config{_exe}\E)?$/$Config::Config{_exe}/; |
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425 | } |
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426 | |
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427 | require Proc::FastSpawn; |
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428 | |
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429 | my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
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430 | Proc::FastSpawn::fd_inherit (fileno $slave); |
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431 | |
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432 | # quick. also doesn't work in win32. of course. what did you expect |
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433 | #local $ENV{PERL5LIB} = join ":", grep !ref, @INC; |
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434 | my %env = %ENV; |
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435 | $env{PERL5LIB} = join +(AnyEvent::Fork::Util::WIN32 ? ";" : ":"), grep !ref, @INC; |
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436 | |
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437 | Proc::FastSpawn::spawn ( |
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438 | $perl, |
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439 | ["perl", "-MAnyEvent::Fork::Serve", "-e", "AnyEvent::Fork::Serve::me", fileno $slave, $$], |
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440 | [map "$_=$env{$_}", keys %env], |
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441 | ) or die "unable to spawn AnyEvent::Fork server: $!"; |
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442 | |
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443 | $self->_new ($fh) |
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444 | } |
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445 | |
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446 | =item $proc = $proc->eval ($perlcode, @args) |
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447 | |
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448 | Evaluates the given C<$perlcode> as ... perl code, while setting C<@_> to |
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449 | the strings specified by C<@args>. |
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450 | |
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451 | This call is meant to do any custom initialisation that might be required |
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452 | (for example, the C<require> method uses it). It's not supposed to be used |
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453 | to completely take over the process, use C<run> for that. |
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454 | |
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455 | The code will usually be executed after this call returns, and there is no |
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456 | way to pass anything back to the calling process. Any evaluation errors |
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457 | will be reported to stderr and cause the process to exit. |
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458 | |
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459 | Returns the process object for easy chaining of method calls. |
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460 | |
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461 | =cut |
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462 | |
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463 | sub eval { |
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464 | my ($self, $code, @args) = @_; |
|
|
465 | |
|
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466 | $self->_cmd (e => $code, @args); |
247 | |
467 | |
248 | $self |
468 | $self |
249 | } |
469 | } |
250 | |
470 | |
|
|
471 | =item $proc = $proc->require ($module, ...) |
|
|
472 | |
|
|
473 | Tries to load the given module(s) into the process |
|
|
474 | |
|
|
475 | Returns the process object for easy chaining of method calls. |
|
|
476 | |
|
|
477 | =cut |
|
|
478 | |
|
|
479 | sub require { |
|
|
480 | my ($self, @modules) = @_; |
|
|
481 | |
|
|
482 | s%::%/%g for @modules; |
|
|
483 | $self->eval ('require "$_.pm" for @_', @modules); |
|
|
484 | |
|
|
485 | $self |
|
|
486 | } |
|
|
487 | |
|
|
488 | =item $proc = $proc->send_fh ($handle, ...) |
|
|
489 | |
|
|
490 | Send one or more file handles (I<not> file descriptors) to the process, |
|
|
491 | to prepare a call to C<run>. |
|
|
492 | |
|
|
493 | The process object keeps a reference to the handles until this is done, |
|
|
494 | so you must not explicitly close the handles. This is most easily |
|
|
495 | accomplished by simply not storing the file handles anywhere after passing |
|
|
496 | them to this method. |
|
|
497 | |
|
|
498 | Returns the process object for easy chaining of method calls. |
|
|
499 | |
|
|
500 | Example: pass an fh to a process, and release it without closing. it will |
|
|
501 | be closed automatically when it is no longer used. |
|
|
502 | |
|
|
503 | $proc->send_fh ($my_fh); |
|
|
504 | undef $my_fh; # free the reference if you want, but DO NOT CLOSE IT |
|
|
505 | |
|
|
506 | =cut |
|
|
507 | |
|
|
508 | sub send_fh { |
|
|
509 | my ($self, @fh) = @_; |
|
|
510 | |
|
|
511 | for my $fh (@fh) { |
|
|
512 | $self->_cmd ("h"); |
|
|
513 | push @{ $self->[2] }, \$fh; |
|
|
514 | } |
|
|
515 | |
|
|
516 | $self |
|
|
517 | } |
|
|
518 | |
|
|
519 | =item $proc = $proc->send_arg ($string, ...) |
|
|
520 | |
|
|
521 | Send one or more argument strings to the process, to prepare a call to |
|
|
522 | C<run>. The strings can be any octet string. |
|
|
523 | |
|
|
524 | Returns the process object for easy chaining of emthod calls. |
|
|
525 | |
|
|
526 | =cut |
|
|
527 | |
|
|
528 | sub send_arg { |
|
|
529 | my ($self, @arg) = @_; |
|
|
530 | |
|
|
531 | $self->_cmd (a => @arg); |
|
|
532 | |
|
|
533 | $self |
|
|
534 | } |
|
|
535 | |
|
|
536 | =item $proc->run ($func, $cb->($fh)) |
|
|
537 | |
|
|
538 | Enter the function specified by the fully qualified name in C<$func> in |
|
|
539 | the process. The function is called with the communication socket as first |
|
|
540 | argument, followed by all file handles and string arguments sent earlier |
|
|
541 | via C<send_fh> and C<send_arg> methods, in the order they were called. |
|
|
542 | |
|
|
543 | If the called function returns, the process exits. |
|
|
544 | |
|
|
545 | Preparing the process can take time - when the process is ready, the |
|
|
546 | callback is invoked with the local communications socket as argument. |
|
|
547 | |
|
|
548 | The process object becomes unusable on return from this function. |
|
|
549 | |
|
|
550 | If the communication socket isn't used, it should be closed on both sides, |
|
|
551 | to save on kernel memory. |
|
|
552 | |
|
|
553 | The socket is non-blocking in the parent, and blocking in the newly |
|
|
554 | created process. The close-on-exec flag is set on both. Even if not used |
|
|
555 | otherwise, the socket can be a good indicator for the existance of the |
|
|
556 | process - if the other process exits, you get a readable event on it, |
|
|
557 | because exiting the process closes the socket (if it didn't create any |
|
|
558 | children using fork). |
|
|
559 | |
|
|
560 | Example: create a template for a process pool, pass a few strings, some |
|
|
561 | file handles, then fork, pass one more string, and run some code. |
|
|
562 | |
|
|
563 | my $pool = AnyEvent::Fork |
|
|
564 | ->new |
|
|
565 | ->send_arg ("str1", "str2") |
|
|
566 | ->send_fh ($fh1, $fh2); |
|
|
567 | |
|
|
568 | for (1..2) { |
|
|
569 | $pool |
|
|
570 | ->fork |
|
|
571 | ->send_arg ("str3") |
|
|
572 | ->run ("Some::function", sub { |
|
|
573 | my ($fh) = @_; |
|
|
574 | |
|
|
575 | # fh is nonblocking, but we trust that the OS can accept these |
|
|
576 | # extra 3 octets anyway. |
|
|
577 | syswrite $fh, "hi #$_\n"; |
|
|
578 | |
|
|
579 | # $fh is being closed here, as we don't store it anywhere |
|
|
580 | }); |
|
|
581 | } |
|
|
582 | |
|
|
583 | # Some::function might look like this - all parameters passed before fork |
|
|
584 | # and after will be passed, in order, after the communications socket. |
|
|
585 | sub Some::function { |
|
|
586 | my ($fh, $str1, $str2, $fh1, $fh2, $str3) = @_; |
|
|
587 | |
|
|
588 | print scalar <$fh>; # prints "hi 1\n" and "hi 2\n" |
|
|
589 | } |
|
|
590 | |
|
|
591 | =cut |
|
|
592 | |
|
|
593 | sub run { |
|
|
594 | my ($self, $func, $cb) = @_; |
|
|
595 | |
|
|
596 | $self->[0] = $cb; |
|
|
597 | $self->_cmd (r => $func); |
|
|
598 | } |
|
|
599 | |
251 | =back |
600 | =back |
|
|
601 | |
|
|
602 | =head1 PORTABILITY NOTES |
|
|
603 | |
|
|
604 | Win32 is a loser - code has been written for this platform, pain has been |
|
|
605 | felt, but in the end, this platform is just too broken - maybe a later |
|
|
606 | version can do it. |
252 | |
607 | |
253 | =head1 AUTHOR |
608 | =head1 AUTHOR |
254 | |
609 | |
255 | Marc Lehmann <schmorp@schmorp.de> |
610 | Marc Lehmann <schmorp@schmorp.de> |
256 | http://home.schmorp.de/ |
611 | http://home.schmorp.de/ |