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Comparing cvsroot/Coro/Coro.pm (file contents):
Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC vs.
Revision 1.30 by root, Sat Aug 11 19:59:19 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 = 0.05; 41$VERSION = 0.45;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 44@EXPORT_OK = qw($current);
35 45
36{ 46{
37 use subs 'async';
38
39 my @async; 47 my @async;
48 my $init;
40 49
41 # this way of handling attributes simply is NOT scalable ;() 50 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 51 sub import {
43 Coro->export_to_level(1, @_); 52 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 53 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 55 my ($package, $ref) = (shift, shift);
47 my @attrs; 56 my @attrs;
48 for (@_) { 57 for (@_) {
49 if ($_ eq "Coro") { 58 if ($_ eq "Coro") {
50 push @async, $ref; 59 push @async, $ref;
60 unless ($init++) {
61 eval q{
62 sub INIT {
63 &async(pop @async) while @async;
64 }
65 };
66 }
51 } else { 67 } else {
52 push @attrs, @_; 68 push @attrs, $_;
53 } 69 }
54 } 70 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 71 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 72 };
57 } 73 }
58 74
59 sub INIT {
60 async pop @async while @async;
61 }
62} 75}
63 76
64=item $main 77=item $main
65 78
66This coroutine represents the main program. 79This coroutine represents the main program.
67 80
68=cut 81=cut
69 82
70our $main = new Coro; 83our $main = new Coro;
71 84
72=item $current 85=item $current (or as function: current)
73 86
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 87The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 88
76=cut 89=cut
77 90
… …
79if ($current) { 92if ($current) {
80 $main->{specific} = $current->{specific}; 93 $main->{specific} = $current->{specific};
81} 94}
82 95
83our $current = $main; 96our $current = $main;
97
98sub current() { $current }
84 99
85=item $idle 100=item $idle
86 101
87The coroutine to switch to when no other coroutine is running. The default 102The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 103implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 108our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 109 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 110 exit(51);
96}; 111};
97 112
98# we really need priorities... 113# this coroutine is necessary because a coroutine
99my @ready = (); # the ready queue. hehe, rather broken ;) 114# cannot destroy itself.
115my @destroy;
116my $manager = new Coro sub {
117 while() {
118 delete ((pop @destroy)->{_coro_state}) while @destroy;
119 &schedule;
120 }
121};
100 122
101# static methods. not really. 123# static methods. not really.
102 124
103=head2 STATIC METHODS 125=head2 STATIC METHODS
104 126
105Static methods are actually functions that operate on the current process only. 127Static methods are actually functions that operate on the current process only.
106 128
107=over 4 129=over 4
108 130
109=item async { ... }; 131=item async { ... } [@args...]
110 132
111Create a new asynchronous process and return it's process object 133Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 134(usually unused). When the sub returns the new process is automatically
113terminated. 135terminated.
114 136
115=cut 137 # create a new coroutine that just prints its arguments
138 async {
139 print "@_\n";
140 } 1,2,3,4;
116 141
142The coderef you submit MUST NOT be a closure that refers to variables
143in an outer scope. This does NOT work. Pass arguments into it instead.
144
145=cut
146
117sub async(&) { 147sub async(&@) {
118 my $pid = new Coro $_[0]; 148 my $pid = new Coro @_;
149 $manager->ready; # this ensures that the stack is cloned from the manager
119 $pid->ready; 150 $pid->ready;
120 $pid; 151 $pid;
121} 152}
122 153
123=item schedule 154=item schedule
… …
126into the ready queue, so calling this function usually means you will 157into the ready queue, so calling this function usually means you will
127never be called again. 158never be called again.
128 159
129=cut 160=cut
130 161
131my $prev;
132
133sub schedule {
134 local @_;
135 # should be done using priorities :(
136 ($prev, $current) = ($current, shift @ready || $idle);
137 Coro::State::transfer($prev, $current);
138}
139
140=item yield 162=item cede
141 163
142Yield to other processes. This function puts the current process into the 164"Cede" to other processes. This function puts the current process into the
143ready queue and calls C<schedule>. 165ready queue and calls C<schedule>, which has the effect of giving up the
166current "timeslice" to other coroutines of the same or higher priority.
144 167
145=cut 168=cut
146 169
147sub yield { 170=item terminate
171
172Terminates the current process.
173
174Future versions of this function will allow result arguments.
175
176=cut
177
178sub terminate {
148 $current->ready; 179 $current->cancel;
149 &schedule; 180 &schedule;
150} 181 die; # NORETURN
151
152=item terminate
153
154Terminates the current process.
155
156=cut
157
158sub terminate {
159 &schedule;
160} 182}
161 183
162=back 184=back
163 185
164# dynamic methods 186# dynamic methods
… …
167 189
168These are the methods you can call on process objects. 190These are the methods you can call on process objects.
169 191
170=over 4 192=over 4
171 193
172=item new Coro \&sub; 194=item new Coro \&sub [, @args...]
173 195
174Create a new process and return it. When the sub returns the process 196Create a new process and return it. When the sub returns the process
175automatically terminates. To start the process you must first put it into 197automatically terminates. To start the process you must first put it into
176the ready queue by calling the ready method. 198the ready queue by calling the ready method.
177 199
200The coderef you submit MUST NOT be a closure that refers to variables
201in an outer scope. This does NOT work. Pass arguments into it instead.
202
178=cut 203=cut
204
205sub _newcoro {
206 terminate &{+shift};
207}
179 208
180sub new { 209sub new {
181 my $class = shift; 210 my $class = shift;
182 my $proc = $_[0];
183 bless { 211 bless {
184 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 212 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
185 }, $class; 213 }, $class;
186} 214}
187 215
188=item $process->ready 216=item $process->ready
189 217
190Put the current process into the ready queue. 218Put the current process into the ready queue.
191 219
192=cut 220=cut
193 221
194sub ready { 222=item $process->cancel
223
224Like C<terminate>, but terminates the specified process instead.
225
226=cut
227
228sub cancel {
195 push @ready, $_[0]; 229 push @destroy, $_[0];
230 $manager->ready;
196} 231}
197 232
198=back 233=back
199 234
200=cut 235=cut
201 236
2021; 2371;
203 238
239=head1 BUGS/LIMITATIONS
240
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 - 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 allow per-thread schedulers, but Coro::State does not yet allow this).
252
204=head1 SEE ALSO 253=head1 SEE ALSO
205 254
206L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 255L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
207L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 256L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
257L<Coro::Handle>, L<Coro::Socket>.
208 258
209=head1 AUTHOR 259=head1 AUTHOR
210 260
211 Marc Lehmann <pcg@goof.com> 261 Marc Lehmann <pcg@goof.com>
212 http://www.goof.com/pcg/marc/ 262 http://www.goof.com/pcg/marc/

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