1 |
root |
1.1 |
=head1 NAME |
2 |
|
|
|
3 |
root |
1.8 |
Coro - coroutine process abstraction |
4 |
root |
1.1 |
|
5 |
|
|
=head1 SYNOPSIS |
6 |
|
|
|
7 |
|
|
use Coro; |
8 |
|
|
|
9 |
root |
1.8 |
async { |
10 |
|
|
# some asynchronous thread of execution |
11 |
root |
1.2 |
}; |
12 |
|
|
|
13 |
root |
1.8 |
# alternatively create an async process like this: |
14 |
root |
1.6 |
|
15 |
root |
1.8 |
sub some_func : Coro { |
16 |
|
|
# some more async code |
17 |
|
|
} |
18 |
|
|
|
19 |
root |
1.22 |
cede; |
20 |
root |
1.2 |
|
21 |
root |
1.1 |
=head1 DESCRIPTION |
22 |
|
|
|
23 |
root |
1.14 |
This module collection manages coroutines. Coroutines are similar to |
24 |
|
|
Threads but don't run in parallel. |
25 |
|
|
|
26 |
|
|
This module is still experimental, see the BUGS section below. |
27 |
|
|
|
28 |
root |
1.20 |
In this module, coroutines are defined as "callchain + lexical variables |
29 |
root |
1.23 |
+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own |
30 |
|
|
callchain, it's own set of lexicals and it's own set of perl's most |
31 |
|
|
important global variables. |
32 |
root |
1.22 |
|
33 |
root |
1.8 |
=cut |
34 |
|
|
|
35 |
|
|
package Coro; |
36 |
|
|
|
37 |
|
|
use Coro::State; |
38 |
|
|
|
39 |
|
|
use base Exporter; |
40 |
|
|
|
41 |
root |
1.29 |
$VERSION = 0.45; |
42 |
root |
1.8 |
|
43 |
root |
1.22 |
@EXPORT = qw(async cede schedule terminate current); |
44 |
root |
1.8 |
@EXPORT_OK = qw($current); |
45 |
|
|
|
46 |
|
|
{ |
47 |
|
|
my @async; |
48 |
root |
1.26 |
my $init; |
49 |
root |
1.8 |
|
50 |
|
|
# this way of handling attributes simply is NOT scalable ;() |
51 |
|
|
sub import { |
52 |
|
|
Coro->export_to_level(1, @_); |
53 |
|
|
my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
54 |
|
|
*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
55 |
|
|
my ($package, $ref) = (shift, shift); |
56 |
|
|
my @attrs; |
57 |
|
|
for (@_) { |
58 |
|
|
if ($_ eq "Coro") { |
59 |
|
|
push @async, $ref; |
60 |
root |
1.26 |
unless ($init++) { |
61 |
|
|
eval q{ |
62 |
|
|
sub INIT { |
63 |
|
|
&async(pop @async) while @async; |
64 |
|
|
} |
65 |
|
|
}; |
66 |
|
|
} |
67 |
root |
1.8 |
} else { |
68 |
root |
1.17 |
push @attrs, $_; |
69 |
root |
1.8 |
} |
70 |
|
|
} |
71 |
root |
1.17 |
return $old ? $old->($package, $ref, @attrs) : @attrs; |
72 |
root |
1.8 |
}; |
73 |
|
|
} |
74 |
|
|
|
75 |
|
|
} |
76 |
|
|
|
77 |
|
|
=item $main |
78 |
root |
1.2 |
|
79 |
root |
1.8 |
This coroutine represents the main program. |
80 |
root |
1.1 |
|
81 |
|
|
=cut |
82 |
|
|
|
83 |
root |
1.9 |
our $main = new Coro; |
84 |
root |
1.8 |
|
85 |
root |
1.19 |
=item $current (or as function: current) |
86 |
root |
1.1 |
|
87 |
root |
1.8 |
The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
88 |
root |
1.1 |
|
89 |
root |
1.8 |
=cut |
90 |
|
|
|
91 |
|
|
# maybe some other module used Coro::Specific before... |
92 |
|
|
if ($current) { |
93 |
|
|
$main->{specific} = $current->{specific}; |
94 |
root |
1.1 |
} |
95 |
|
|
|
96 |
root |
1.9 |
our $current = $main; |
97 |
root |
1.19 |
|
98 |
|
|
sub current() { $current } |
99 |
root |
1.9 |
|
100 |
|
|
=item $idle |
101 |
|
|
|
102 |
|
|
The coroutine to switch to when no other coroutine is running. The default |
103 |
|
|
implementation prints "FATAL: deadlock detected" and exits. |
104 |
|
|
|
105 |
|
|
=cut |
106 |
|
|
|
107 |
|
|
# should be done using priorities :( |
108 |
|
|
our $idle = new Coro sub { |
109 |
|
|
print STDERR "FATAL: deadlock detected\n"; |
110 |
|
|
exit(51); |
111 |
|
|
}; |
112 |
root |
1.8 |
|
113 |
root |
1.24 |
# this coroutine is necessary because a coroutine |
114 |
|
|
# cannot destroy itself. |
115 |
|
|
my @destroy; |
116 |
|
|
my $manager = new Coro sub { |
117 |
|
|
while() { |
118 |
|
|
delete ((pop @destroy)->{_coro_state}) while @destroy; |
119 |
|
|
&schedule; |
120 |
|
|
} |
121 |
|
|
}; |
122 |
|
|
|
123 |
root |
1.8 |
# static methods. not really. |
124 |
|
|
|
125 |
|
|
=head2 STATIC METHODS |
126 |
|
|
|
127 |
|
|
Static methods are actually functions that operate on the current process only. |
128 |
|
|
|
129 |
|
|
=over 4 |
130 |
|
|
|
131 |
root |
1.13 |
=item async { ... } [@args...] |
132 |
root |
1.8 |
|
133 |
|
|
Create a new asynchronous process and return it's process object |
134 |
|
|
(usually unused). When the sub returns the new process is automatically |
135 |
|
|
terminated. |
136 |
|
|
|
137 |
root |
1.13 |
# create a new coroutine that just prints its arguments |
138 |
|
|
async { |
139 |
|
|
print "@_\n"; |
140 |
|
|
} 1,2,3,4; |
141 |
|
|
|
142 |
|
|
The coderef you submit MUST NOT be a closure that refers to variables |
143 |
|
|
in an outer scope. This does NOT work. Pass arguments into it instead. |
144 |
|
|
|
145 |
root |
1.8 |
=cut |
146 |
|
|
|
147 |
root |
1.13 |
sub async(&@) { |
148 |
|
|
my $pid = new Coro @_; |
149 |
root |
1.24 |
$manager->ready; # this ensures that the stack is cloned from the manager |
150 |
root |
1.11 |
$pid->ready; |
151 |
|
|
$pid; |
152 |
root |
1.8 |
} |
153 |
root |
1.1 |
|
154 |
root |
1.8 |
=item schedule |
155 |
root |
1.6 |
|
156 |
root |
1.8 |
Calls the scheduler. Please note that the current process will not be put |
157 |
|
|
into the ready queue, so calling this function usually means you will |
158 |
|
|
never be called again. |
159 |
root |
1.1 |
|
160 |
|
|
=cut |
161 |
|
|
|
162 |
root |
1.22 |
=item cede |
163 |
root |
1.1 |
|
164 |
root |
1.22 |
"Cede" to other processes. This function puts the current process into the |
165 |
|
|
ready queue and calls C<schedule>, which has the effect of giving up the |
166 |
|
|
current "timeslice" to other coroutines of the same or higher priority. |
167 |
root |
1.7 |
|
168 |
root |
1.8 |
=cut |
169 |
|
|
|
170 |
|
|
=item terminate |
171 |
root |
1.7 |
|
172 |
root |
1.8 |
Terminates the current process. |
173 |
root |
1.1 |
|
174 |
root |
1.13 |
Future versions of this function will allow result arguments. |
175 |
|
|
|
176 |
root |
1.1 |
=cut |
177 |
|
|
|
178 |
root |
1.8 |
sub terminate { |
179 |
root |
1.28 |
$current->cancel; |
180 |
root |
1.23 |
&schedule; |
181 |
root |
1.28 |
die; # NORETURN |
182 |
root |
1.1 |
} |
183 |
root |
1.6 |
|
184 |
root |
1.8 |
=back |
185 |
|
|
|
186 |
|
|
# dynamic methods |
187 |
|
|
|
188 |
|
|
=head2 PROCESS METHODS |
189 |
|
|
|
190 |
|
|
These are the methods you can call on process objects. |
191 |
root |
1.6 |
|
192 |
root |
1.8 |
=over 4 |
193 |
|
|
|
194 |
root |
1.13 |
=item new Coro \&sub [, @args...] |
195 |
root |
1.8 |
|
196 |
|
|
Create a new process and return it. When the sub returns the process |
197 |
|
|
automatically terminates. To start the process you must first put it into |
198 |
|
|
the ready queue by calling the ready method. |
199 |
root |
1.6 |
|
200 |
root |
1.13 |
The coderef you submit MUST NOT be a closure that refers to variables |
201 |
|
|
in an outer scope. This does NOT work. Pass arguments into it instead. |
202 |
|
|
|
203 |
root |
1.6 |
=cut |
204 |
|
|
|
205 |
root |
1.13 |
sub _newcoro { |
206 |
|
|
terminate &{+shift}; |
207 |
|
|
} |
208 |
|
|
|
209 |
root |
1.8 |
sub new { |
210 |
|
|
my $class = shift; |
211 |
|
|
bless { |
212 |
root |
1.13 |
_coro_state => (new Coro::State $_[0] && \&_newcoro, @_), |
213 |
root |
1.8 |
}, $class; |
214 |
|
|
} |
215 |
root |
1.6 |
|
216 |
root |
1.8 |
=item $process->ready |
217 |
root |
1.1 |
|
218 |
root |
1.8 |
Put the current process into the ready queue. |
219 |
root |
1.1 |
|
220 |
root |
1.8 |
=cut |
221 |
root |
1.28 |
|
222 |
|
|
=item $process->cancel |
223 |
|
|
|
224 |
|
|
Like C<terminate>, but terminates the specified process instead. |
225 |
|
|
|
226 |
|
|
=cut |
227 |
|
|
|
228 |
|
|
sub cancel { |
229 |
|
|
push @destroy, $_[0]; |
230 |
|
|
$manager->ready; |
231 |
root |
1.8 |
} |
232 |
root |
1.1 |
|
233 |
root |
1.8 |
=back |
234 |
root |
1.2 |
|
235 |
root |
1.8 |
=cut |
236 |
root |
1.2 |
|
237 |
root |
1.8 |
1; |
238 |
root |
1.14 |
|
239 |
root |
1.17 |
=head1 BUGS/LIMITATIONS |
240 |
root |
1.14 |
|
241 |
|
|
- could be faster, especially when the core would introduce special |
242 |
|
|
support for coroutines (like it does for threads). |
243 |
|
|
- there is still a memleak on coroutine termination that I could not |
244 |
|
|
identify. Could be as small as a single SV. |
245 |
|
|
- this module is not well-tested. |
246 |
root |
1.17 |
- if variables or arguments "disappear" (become undef) or become |
247 |
|
|
corrupted please contact the author so he cen iron out the |
248 |
|
|
remaining bugs. |
249 |
|
|
- this module is not thread-safe. You must only ever use this module from |
250 |
|
|
the same thread (this requirement might be loosened in the future to |
251 |
root |
1.20 |
allow per-thread schedulers, but Coro::State does not yet allow this). |
252 |
root |
1.9 |
|
253 |
|
|
=head1 SEE ALSO |
254 |
|
|
|
255 |
|
|
L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, |
256 |
root |
1.25 |
L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>, |
257 |
root |
1.26 |
L<Coro::Handle>, L<Coro::Socket>. |
258 |
root |
1.1 |
|
259 |
|
|
=head1 AUTHOR |
260 |
|
|
|
261 |
|
|
Marc Lehmann <pcg@goof.com> |
262 |
|
|
http://www.goof.com/pcg/marc/ |
263 |
|
|
|
264 |
|
|
=cut |
265 |
|
|
|