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Comparing Coro/Coro.pm (file contents):
Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC vs.
Revision 1.25 by root, Wed Jul 25 21:12:57 2001 UTC

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
23This module collection manages coroutines. Coroutines are similar to
24Threads but don't run in parallel.
25
26This module is still experimental, see the BUGS section below.
27
28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
27use Coro::State; 37use Coro::State;
28 38
29use base Exporter; 39use base Exporter;
30 40
31$VERSION = 0.04; 41$VERSION = 0.12;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 44@EXPORT_OK = qw($current);
35 45
36{ 46{
37 use subs 'async';
38
39 my @async; 47 my @async;
40 48
41 # this way of handling attributes simply is NOT scalable ;() 49 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 50 sub import {
43 Coro->export_to_level(1, @_); 51 Coro->export_to_level(1, @_);
47 my @attrs; 55 my @attrs;
48 for (@_) { 56 for (@_) {
49 if ($_ eq "Coro") { 57 if ($_ eq "Coro") {
50 push @async, $ref; 58 push @async, $ref;
51 } else { 59 } else {
52 push @attrs, @_; 60 push @attrs, $_;
53 } 61 }
54 } 62 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 63 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 64 };
57 } 65 }
58 66
59 sub INIT { 67 sub INIT {
60 async pop @async while @async; 68 &async(pop @async) while @async;
61 } 69 }
62} 70}
63 71
64=item $main 72=item $main
65 73
67 75
68=cut 76=cut
69 77
70our $main = new Coro; 78our $main = new Coro;
71 79
72=item $current 80=item $current (or as function: current)
73 81
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 82The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 83
76=cut 84=cut
77 85
79if ($current) { 87if ($current) {
80 $main->{specific} = $current->{specific}; 88 $main->{specific} = $current->{specific};
81} 89}
82 90
83our $current = $main; 91our $current = $main;
92
93sub current() { $current }
84 94
85=item $idle 95=item $idle
86 96
87The coroutine to switch to when no other coroutine is running. The default 97The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 98implementation prints "FATAL: deadlock detected" and exits.
93our $idle = new Coro sub { 103our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 104 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 105 exit(51);
96}; 106};
97 107
108# this coroutine is necessary because a coroutine
109# cannot destroy itself.
110my @destroy;
111my $manager = new Coro sub {
112 while() {
113 delete ((pop @destroy)->{_coro_state}) while @destroy;
114 &schedule;
115 }
116};
117
98# we really need priorities... 118# we really need priorities...
99my @ready = (); # the ready queue. hehe, rather broken ;) 119my @ready; # the ready queue. hehe, rather broken ;)
100 120
101# static methods. not really. 121# static methods. not really.
102 122
103=head2 STATIC METHODS 123=head2 STATIC METHODS
104 124
105Static methods are actually functions that operate on the current process only. 125Static methods are actually functions that operate on the current process only.
106 126
107=over 4 127=over 4
108 128
109=item async { ... }; 129=item async { ... } [@args...]
110 130
111Create a new asynchronous process and return it's process object 131Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 132(usually unused). When the sub returns the new process is automatically
113terminated. 133terminated.
114 134
115=cut 135 # create a new coroutine that just prints its arguments
136 async {
137 print "@_\n";
138 } 1,2,3,4;
116 139
140The coderef you submit MUST NOT be a closure that refers to variables
141in an outer scope. This does NOT work. Pass arguments into it instead.
142
143=cut
144
117sub async(&) { 145sub async(&@) {
118 (new Coro $_[0])->ready; 146 my $pid = new Coro @_;
147 $manager->ready; # this ensures that the stack is cloned from the manager
148 $pid->ready;
149 $pid;
119} 150}
120 151
121=item schedule 152=item schedule
122 153
123Calls the scheduler. Please note that the current process will not be put 154Calls the scheduler. Please note that the current process will not be put
132 # should be done using priorities :( 163 # should be done using priorities :(
133 ($prev, $current) = ($current, shift @ready || $idle); 164 ($prev, $current) = ($current, shift @ready || $idle);
134 Coro::State::transfer($prev, $current); 165 Coro::State::transfer($prev, $current);
135} 166}
136 167
137=item yield 168=item cede
138 169
139Yield to other processes. This function puts the current process into the 170"Cede" to other processes. This function puts the current process into the
140ready queue and calls C<schedule>. 171ready queue and calls C<schedule>, which has the effect of giving up the
172current "timeslice" to other coroutines of the same or higher priority.
141 173
142=cut 174=cut
143 175
144sub yield { 176sub cede {
145 $current->ready; 177 $current->ready;
146 &schedule; 178 &schedule;
147} 179}
148 180
149=item terminate 181=item terminate
150 182
151Terminates the current process. 183Terminates the current process.
152 184
185Future versions of this function will allow result arguments.
186
153=cut 187=cut
154 188
155sub terminate { 189sub terminate {
190 push @destroy, $current;
191 $manager->ready;
156 &schedule; 192 &schedule;
193 # NORETURN
157} 194}
158 195
159=back 196=back
160 197
161# dynamic methods 198# dynamic methods
164 201
165These are the methods you can call on process objects. 202These are the methods you can call on process objects.
166 203
167=over 4 204=over 4
168 205
169=item new Coro \&sub; 206=item new Coro \&sub [, @args...]
170 207
171Create a new process and return it. When the sub returns the process 208Create a new process and return it. When the sub returns the process
172automatically terminates. To start the process you must first put it into 209automatically terminates. To start the process you must first put it into
173the ready queue by calling the ready method. 210the ready queue by calling the ready method.
174 211
212The coderef you submit MUST NOT be a closure that refers to variables
213in an outer scope. This does NOT work. Pass arguments into it instead.
214
175=cut 215=cut
216
217sub _newcoro {
218 terminate &{+shift};
219}
176 220
177sub new { 221sub new {
178 my $class = shift; 222 my $class = shift;
179 my $proc = $_[0];
180 bless { 223 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 224 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 225 }, $class;
183} 226}
184 227
185=item $process->ready 228=item $process->ready
186 229
196 239
197=cut 240=cut
198 241
1991; 2421;
200 243
244=head1 BUGS/LIMITATIONS
245
246 - could be faster, especially when the core would introduce special
247 support for coroutines (like it does for threads).
248 - there is still a memleak on coroutine termination that I could not
249 identify. Could be as small as a single SV.
250 - this module is not well-tested.
251 - if variables or arguments "disappear" (become undef) or become
252 corrupted please contact the author so he cen iron out the
253 remaining bugs.
254 - this module is not thread-safe. You must only ever use this module from
255 the same thread (this requirement might be loosened in the future to
256 allow per-thread schedulers, but Coro::State does not yet allow this).
257
201=head1 SEE ALSO 258=head1 SEE ALSO
202 259
203L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 260L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
204L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 261L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
262L<Coro::L<Coro::Handle>, L<Coro::Socket>.
205 263
206=head1 AUTHOR 264=head1 AUTHOR
207 265
208 Marc Lehmann <pcg@goof.com> 266 Marc Lehmann <pcg@goof.com>
209 http://www.goof.com/pcg/marc/ 267 http://www.goof.com/pcg/marc/

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