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Comparing Coro/Coro.pm (file contents):
Revision 1.8 by root, Sat Jul 14 22:14:21 2001 UTC vs.
Revision 1.23 by root, Mon Jul 23 04:23:32 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 = 0.03; 41$VERSION = 0.10;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($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
64my $idle = new Coro sub {
65 &yield while 1;
66};
67
68=item $main 72=item $main
69 73
70This coroutine represents the main program. 74This coroutine represents the main program.
71 75
72=cut 76=cut
73 77
74$main = new Coro; 78our $main = new Coro;
75 79
76=item $current 80=item $current (or as function: current)
77 81
78The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 82The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
79 83
80=cut 84=cut
81 85
82# maybe some other module used Coro::Specific before... 86# maybe some other module used Coro::Specific before...
83if ($current) { 87if ($current) {
84 $main->{specific} = $current->{specific}; 88 $main->{specific} = $current->{specific};
85} 89}
86 90
87$current = $main; 91our $current = $main;
92
93sub current() { $current }
94
95=item $idle
96
97The coroutine to switch to when no other coroutine is running. The default
98implementation prints "FATAL: deadlock detected" and exits.
99
100=cut
101
102# should be done using priorities :(
103our $idle = new Coro sub {
104 print STDERR "FATAL: deadlock detected\n";
105 exit(51);
106};
88 107
89# we really need priorities... 108# we really need priorities...
90my @ready = (); # the ready queue. hehe, rather broken ;) 109my @ready; # the ready queue. hehe, rather broken ;)
91 110
92# static methods. not really. 111# static methods. not really.
93 112
94=head2 STATIC METHODS 113=head2 STATIC METHODS
95 114
96Static methods are actually functions that operate on the current process only. 115Static methods are actually functions that operate on the current process only.
97 116
98=over 4 117=over 4
99 118
100=item async { ... }; 119=item async { ... } [@args...]
101 120
102Create a new asynchronous process and return it's process object 121Create a new asynchronous process and return it's process object
103(usually unused). When the sub returns the new process is automatically 122(usually unused). When the sub returns the new process is automatically
104terminated. 123terminated.
105 124
106=cut 125 # create a new coroutine that just prints its arguments
126 async {
127 print "@_\n";
128 } 1,2,3,4;
107 129
130The coderef you submit MUST NOT be a closure that refers to variables
131in an outer scope. This does NOT work. Pass arguments into it instead.
132
133=cut
134
108sub async(&) { 135sub async(&@) {
109 (new Coro $_[0])->ready; 136 my $pid = new Coro @_;
137 $pid->ready;
138 $pid;
110} 139}
111 140
112=item schedule 141=item schedule
113 142
114Calls the scheduler. Please note that the current process will not be put 143Calls the scheduler. Please note that the current process will not be put
… …
118=cut 147=cut
119 148
120my $prev; 149my $prev;
121 150
122sub schedule { 151sub schedule {
152 # should be done using priorities :(
123 ($prev, $current) = ($current, shift @ready); 153 ($prev, $current) = ($current, shift @ready || $idle);
124 Coro::State::transfer($prev, $current); 154 Coro::State::transfer($prev, $current);
125} 155}
126 156
127=item yield 157=item cede
128 158
129Yield to other processes. This function puts the current process into the 159"Cede" to other processes. This function puts the current process into the
130ready queue and calls C<schedule>. 160ready queue and calls C<schedule>, which has the effect of giving up the
161current "timeslice" to other coroutines of the same or higher priority.
131 162
132=cut 163=cut
133 164
134sub yield { 165sub cede {
135 $current->ready; 166 $current->ready;
136 &schedule; 167 &schedule;
137} 168}
138 169
139=item terminate 170=item terminate
140 171
141Terminates the current process. 172Terminates the current process.
142 173
174Future versions of this function will allow result arguments.
175
143=cut 176=cut
177
178# this coroutine is necessary because a coroutine
179# cannot destroy itself.
180my @destroy;
181my $terminate = new Coro sub {
182 while() {
183 delete ((pop @destroy)->{_coro_state}) while @destroy;
184 &schedule;
185 }
186};
144 187
145sub terminate { 188sub terminate {
189 push @destroy, $current;
190 $terminate->ready;
146 &schedule; 191 &schedule;
192 # NORETURN
147} 193}
148 194
149=back 195=back
150 196
151# dynamic methods 197# dynamic methods
… …
154 200
155These are the methods you can call on process objects. 201These are the methods you can call on process objects.
156 202
157=over 4 203=over 4
158 204
159=item new Coro \&sub; 205=item new Coro \&sub [, @args...]
160 206
161Create a new process and return it. When the sub returns the process 207Create a new process and return it. When the sub returns the process
162automatically terminates. To start the process you must first put it into 208automatically terminates. To start the process you must first put it into
163the ready queue by calling the ready method. 209the ready queue by calling the ready method.
164 210
211The coderef you submit MUST NOT be a closure that refers to variables
212in an outer scope. This does NOT work. Pass arguments into it instead.
213
165=cut 214=cut
215
216sub _newcoro {
217 terminate &{+shift};
218}
166 219
167sub new { 220sub new {
168 my $class = shift; 221 my $class = shift;
169 my $proc = $_[0];
170 bless { 222 bless {
171 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 223 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
172 }, $class; 224 }, $class;
173} 225}
174 226
175=item $process->ready 227=item $process->ready
176 228
… …
186 238
187=cut 239=cut
188 240
1891; 2411;
190 242
243=head1 BUGS/LIMITATIONS
244
245 - could be faster, especially when the core would introduce special
246 support for coroutines (like it does for threads).
247 - there is still a memleak on coroutine termination that I could not
248 identify. Could be as small as a single SV.
249 - this module is not well-tested.
250 - if variables or arguments "disappear" (become undef) or become
251 corrupted please contact the author so he cen iron out the
252 remaining bugs.
253 - this module is not thread-safe. You must only ever use this module from
254 the same thread (this requirement might be loosened in the future to
255 allow per-thread schedulers, but Coro::State does not yet allow this).
256
257=head1 SEE ALSO
258
259L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
260L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.
261
191=head1 AUTHOR 262=head1 AUTHOR
192 263
193 Marc Lehmann <pcg@goof.com> 264 Marc Lehmann <pcg@goof.com>
194 http://www.goof.com/pcg/marc/ 265 http://www.goof.com/pcg/marc/
195 266

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