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

Comparing Coro/Coro.pm (file contents):
Revision 1.4 by root, Tue Jul 3 05:05:45 2001 UTC vs.
Revision 1.12 by root, Sun Jul 15 15:58:16 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	$VERSION = 0.05;
		32
		33	@EXPORT = qw(async yield schedule);
		34	@EXPORT_OK = qw($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	my $pid = new Coro $_[0];
58	};	119	$pid->ready;
		120	$pid;
		121	}
59		122
60	=item $error, $error_msg, $error_coro	123	=item schedule
61		124
62	This coroutine will be called on fatal errors. C<$error_msg> and	125	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,	126	into the ready queue, so calling this function usually means you will
64	respectively.	127	never be called again.
65		128
66	=cut	129	=cut
67		130
68	$error_msg =	131	my $prev;
69	$error_coro = undef;
70		132
71	$error = _newprocess {	133	sub schedule {
72	print STDERR "FATAL: $error_msg\nprogram aborted\n";	134	local @_;
73	exit 250;	135	# should be done using priorities :(
74	};	136	($prev, $current) = ($current, shift @ready \|\| $idle);
		137	Coro::State::transfer($prev, $current);
		138	}
75		139
76	=item $coro = new $coderef [, @args]	140	=item yield
77		141
78	Create a new coroutine and return it. The first C<resume> call to this	142	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	143	ready queue and calls C<schedule>.
80	should return a coroutine to switch to. If, after returning, the coroutine	144
81	is C<resume>d again it starts execution again at the givne coderef.	145	=cut
		146
		147	sub yield {
		148	$current->ready;
		149	&schedule;
		150	}
		151
		152	=item terminate
		153
		154	Terminates the current process.
		155
		156	=cut
		157
		158	sub terminate {
		159	&schedule;
		160	}
		161
		162	=back
		163
		164	# dynamic methods
		165
		166	=head2 PROCESS METHODS
		167
		168	These are the methods you can call on process objects.
		169
		170	=over 4
		171
		172	=item new Coro \⊂
		173
		174	Create a new process and return it. When the sub returns the process
		175	automatically terminates. To start the process you must first put it into
		176	the ready queue by calling the ready method.
82		177
83	=cut	178	=cut
84		179
85	sub new {	180	sub new {
86	my $class = $_[0];	181	my $class = shift;
87	my $proc = $_[1];	182	my $proc = $_[0];
88	bless _newprocess {	183	bless {
89	do {	184	_coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc),
90	eval { &$proc->resume };
91	if ($@) {
92	($error_msg, $error_coro) = ($@, $current);
93	$error->resume;
94	}
95	} while (1);
96	}, $class;	185	}, $class;
97	}	186	}
98		187
99	=item $coro->resume	188	=item $process->ready
100		189
101	Resume execution at the given coroutine.	190	Put the current process into the ready queue.
102		191
103	=cut	192	=cut
104		193
105	my $prev;	194	sub ready {
106		195	push @ready, $_[0];
107	sub resume {
108	$prev = $current; $current = $_[0];
109	_transfer($prev, $current);
110	}	196	}
		197
		198	=back
		199
		200	=cut
111		201
112	1;	202	1;
113		203
114	=back
115
116	=head1 BUGS
117
118	This module has not yet been extensively tested.
119
120	=head1 SEE ALSO	204	=head1 SEE ALSO
121		205
122	L<Coro::Process>, L<Coro::Signal>.	206	L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
		207	L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.
123		208
124	=head1 AUTHOR	209	=head1 AUTHOR
125		210
126	Marc Lehmann <pcg@goof.com>	211	Marc Lehmann <pcg@goof.com>
127	http://www.goof.com/pcg/marc/	212	http://www.goof.com/pcg/marc/

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Comparing Coro/Coro.pm (file contents): Revision 1.4 by root, Tue Jul 3 05:05:45 2001 UTC vs. Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.4 by root, Tue Jul 3 05:05:45 2001 UTC vs.
Revision 1.12 by root, Sun Jul 15 15:58:16 2001 UTC