[ViewVC] Diff of: cvs/Coro/Coro.pm

Comparing Coro/Coro.pm (file contents):
Revision 1.3 by root, Tue Jul 3 04:02:31 2001 UTC vs.
Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC

1	=head1 NAME	1	=head1 NAME
2		2
3	Coro - create and manage coroutines	3	Coro - coroutine process abstraction
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use Coro;	7	use Coro;
8		8
9	$new = new Coro sub {	9	async {
10	print "in coroutine, switching back\n";	10	# some asynchronous thread of execution
11	$Coro::main->resume;
12	print "in coroutine again, switching back\n";
13	$Coro::main->resume;
14	};	11	};
15		12
16	print "in main, switching to coroutine\n";	13	# alternatively create an async process like this:
17	$new->resume;	14
18	print "back in main, switch to coroutine again\n";	15	sub some_func : Coro {
19	$new->resume;	16	# some more async code
20	print "back in main\n";	17	}
		18
		19	yield;
21		20
22	=head1 DESCRIPTION	21	=head1 DESCRIPTION
23		22
24	This module implements coroutines. Coroutines, similar to continuations,	23	=cut
25	allow you to run more than one "thread of execution" in parallel. Unlike
26	threads this, only voluntary switching is used so locking problems are
27	greatly reduced.
28		24
29	Although this is the "main" module of the Coro family it provides only	25	package Coro;
30	low-level functionality. See L<Coro::Process> and related modules for a	26
31	more useful process abstraction including scheduling.	27	use Coro::State;
		28
		29	use base Exporter;
		30
		31	$VERSION = 0.04;
		32
		33	@EXPORT = qw(async yield schedule);
		34	@EXPORT_OK = qw($current);
		35
		36	{
		37	use subs 'async';
		38
		39	my @async;
		40
		41	# this way of handling attributes simply is NOT scalable ;()
		42	sub import {
		43	Coro->export_to_level(1, @_);
		44	my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
		45	*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
		46	my ($package, $ref) = (shift, shift);
		47	my @attrs;
		48	for (@_) {
		49	if ($_ eq "Coro") {
		50	push @async, $ref;
		51	} else {
		52	push @attrs, @_;
		53	}
		54	}
		55	return $old ? $old->($package, $name, @attrs) : @attrs;
		56	};
		57	}
		58
		59	sub INIT {
		60	async pop @async while @async;
		61	}
		62	}
		63
		64	=item $main
		65
		66	This coroutine represents the main program.
		67
		68	=cut
		69
		70	our $main = new Coro;
		71
		72	=item $current
		73
		74	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
		75
		76	=cut
		77
		78	# maybe some other module used Coro::Specific before...
		79	if ($current) {
		80	$main->{specific} = $current->{specific};
		81	}
		82
		83	our $current = $main;
		84
		85	=item $idle
		86
		87	The coroutine to switch to when no other coroutine is running. The default
		88	implementation prints "FATAL: deadlock detected" and exits.
		89
		90	=cut
		91
		92	# should be done using priorities :(
		93	our $idle = new Coro sub {
		94	print STDERR "FATAL: deadlock detected\n";
		95	exit(51);
		96	};
		97
		98	# we really need priorities...
		99	my @ready = (); # the ready queue. hehe, rather broken ;)
		100
		101	# static methods. not really.
		102
		103	=head2 STATIC METHODS
		104
		105	Static methods are actually functions that operate on the current process only.
32		106
33	=over 4	107	=over 4
34		108
35	=cut	109	=item async { ... };
36		110
37	package Coro;	111	Create a new asynchronous process and return it's process object
		112	(usually unused). When the sub returns the new process is automatically
		113	terminated.
38		114
39	BEGIN {
40	$VERSION = 0.01;
41
42	require XSLoader;
43	XSLoader::load Coro, $VERSION;
44	}
45
46	=item $main
47
48	This coroutine represents the main program.
49
50	=item $current
51
52	The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
53
54	=cut	115	=cut
55		116
56	$main = $current = _newprocess {	117	sub async(&) {
57	# never being called	118	(new Coro $_[0])->ready;
58	};	119	}
59		120
60	=item $error, $error_msg, $error_coro	121	=item schedule
61		122
62	This coroutine will be called on fatal errors. C<$error_msg> and	123	Calls the scheduler. Please note that the current process will not be put
63	C<$error_coro> return the error message and the error-causing coroutine,	124	into the ready queue, so calling this function usually means you will
64	respectively.	125	never be called again.
65		126
66	=cut	127	=cut
67		128
68	$error_msg =	129	my $prev;
69	$error_coro = undef;
70		130
71	$error = _newprocess {	131	sub schedule {
72	print STDERR "FATAL: $error_msg\nprogram aborted\n";	132	# should be done using priorities :(
73	exit 250;	133	($prev, $current) = ($current, shift @ready \|\| $idle);
74	};	134	Coro::State::transfer($prev, $current);
		135	}
75		136
76	=item $coro = new $coderef [, @args]	137	=item yield
77		138
78	Create a new coroutine and return it. The first C<resume> call to this	139	Yield to other processes. This function puts the current process into the
79	coroutine will start execution at the given coderef. If it returns it	140	ready queue and calls C<schedule>.
80	should return a coroutine to switch to. If, after returning, the coroutine	141
81	is C<resume>d again it starts execution again at the givne coderef.	142	=cut
		143
		144	sub yield {
		145	$current->ready;
		146	&schedule;
		147	}
		148
		149	=item terminate
		150
		151	Terminates the current process.
		152
		153	=cut
		154
		155	sub terminate {
		156	&schedule;
		157	}
		158
		159	=back
		160
		161	# dynamic methods
		162
		163	=head2 PROCESS METHODS
		164
		165	These are the methods you can call on process objects.
		166
		167	=over 4
		168
		169	=item new Coro \⊂
		170
		171	Create a new process and return it. When the sub returns the process
		172	automatically terminates. To start the process you must first put it into
		173	the ready queue by calling the ready method.
82		174
83	=cut	175	=cut
84		176
85	sub new {	177	sub new {
86	my $class = $_[0];	178	my $class = shift;
87	my $proc = $_[1];	179	my $proc = $_[0];
88	bless _newprocess {	180	bless {
89	do {	181	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
90	eval { &$proc->resume };
91	if ($@) {
92	($error_msg, $error_coro) = ($@, $current);
93	$error->resume;
94	}
95	} while ();
96	}, $class;	182	}, $class;
97	}	183	}
98		184
99	=item $coro->resume	185	=item $process->ready
100		186
101	Resume execution at the given coroutine.	187	Put the current process into the ready queue.
102		188
103	=cut	189	=cut
104		190
105	my $prev;	191	sub ready {
106		192	push @ready, $_[0];
107	sub resume {
108	$prev = $current; $current = $_[0];
109	_transfer($prev, $current);
110	}	193	}
		194
		195	=back
		196
		197	=cut
111		198
112	1;	199	1;
113		200
114	=back
115
116	=head1 BUGS
117
118	This module has not yet been extensively tested.
119
120	=head1 SEE ALSO	201	=head1 SEE ALSO
121		202
122	L<Coro::Process>, L<Coro::Signal>.	203	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
		204	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.
123		205
124	=head1 AUTHOR	206	=head1 AUTHOR
125		207
126	Marc Lehmann <pcg@goof.com>	208	Marc Lehmann <pcg@goof.com>
127	http://www.goof.com/pcg/marc/	209	http://www.goof.com/pcg/marc/

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Comparing Coro/Coro.pm (file contents): Revision 1.3 by root, Tue Jul 3 04:02:31 2001 UTC vs. Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.3 by root, Tue Jul 3 04:02:31 2001 UTC vs.
Revision 1.10 by root, Sun Jul 15 02:36:54 2001 UTC