Coro/Coro/AIO.pm

=head1 NAME

Coro::AIO - truly asynchronous file and directory I/O

=head1 SYNOPSIS

   use Coro::AIO;

   # can now use any of the aio requests your IO::AIO module supports.

   # read 1MB of /etc/passwd, without blocking other coroutines
   my $fh = aio_open "/etc/passwd", O_RDONLY, 0
      or die "/etc/passwd: $!";
   aio_read $fh, 0, 1_000_000, my $buf, 0
      or die "aio_read: $!";
   aio_close $fh;

=head1 DESCRIPTION

This module is an L<AnyEvent> user, you need to make sure that you use and
run a supported event loop.

This module implements a thin wrapper around L<IO::AIO>. All of
the functions that expect a callback are being wrapped by this module.

The API is exactly the same as that of the corresponding IO::AIO routines,
except that you have to specify I<all> arguments I<except> the callback
argument. Instead the routines return the values normally passed to the
callback. Everything else, including C<$!> and perls stat cache, are set
as expected after these functions return.

You can mix calls to C<IO::AIO> functions with calls to this module. You
I<must not>, however, call these routines from within IO::AIO callbacks,
as this causes a deadlock. Start a coro inside the callback instead.

This module also loads L<AnyEvent::AIO> to integrate into the event loop
in use, so please refer to its (and L<AnyEvent>'s) documentation on how it
selects an appropriate event module.

All other functions exported by default by IO::AIO (e.g. C<aioreq_pri>)
will be exported by default by Coro::AIO, too.

Functions that can be optionally imported from IO::AIO can be imported
from Coro::AIO or can be called directly, e.g. C<Coro::AIO::nreqs>.

You cannot specify priorities with C<aioreq_pri> if your coroutine has a
non-zero priority, as this module overwrites the request priority with the
current coroutine priority in that case.

For your convenience, here are the changed function signatures for most
of the requests, for documentation of these functions please have a look
at L<IO::AIO|the IO::AIO manual>. Note that requests added by newer
versions of L<IO::AIO> will be automatically wrapped as well.

=over 4

=cut

package Coro::AIO;

use strict qw(subs vars);

use IO::AIO 3.1 ();
use AnyEvent::AIO ();

use Coro ();
use Coro::AnyEvent ();

use base Exporter::;

our $VERSION = 5.13;

our @EXPORT    = (@IO::AIO::EXPORT, qw(aio_wait));
our @EXPORT_OK = @IO::AIO::EXPORT_OK;
our $AUTOLOAD;

{
   my @reqs = @IO::AIO::AIO_REQ ? @IO::AIO::AIO_REQ : @IO::AIO::EXPORT;
   my %reqs = map +($_ => 1), @reqs;

   eval
      join "",
         map "sub $_(" . (prototype "IO::AIO::$_") . ");",
            grep !$reqs{$_},
                @IO::AIO::EXPORT, @EXPORT_OK;

   for my $sub (@reqs) {
      push @EXPORT, $sub;

      my $iosub = "IO::AIO::$sub";
      my $proto = prototype $iosub;

      $proto =~ s/;?\$$// or die "$iosub: unable to remove callback slot from prototype";

      _register "Coro::AIO::$sub", $proto, \&{$iosub};
   }

   _register "Coro::AIO::aio_wait", '$', \&IO::AIO::REQ::cb;
}

sub AUTOLOAD {
   (my $func = $AUTOLOAD) =~ s/^.*:://;
   *$AUTOLOAD = \&{"IO::AIO::$func"};
   goto &$AUTOLOAD;
}

=item @results = aio_wait $req

This is not originally an IO::AIO request: what it does is to wait for
C<$req> to finish and return the results. This is most useful with
C<aio_group> requests.

Is currently implemented by replacing the C<$req> callback (and is very
much like a wrapper around C<< $req->cb () >>).

=item $fh = aio_open $pathname, $flags, $mode

=item $status = aio_close $fh

=item $retval = aio_read  $fh,$offset,$length, $data,$dataoffset

=item $retval = aio_write $fh,$offset,$length, $data,$dataoffset

=item $retval = aio_sendfile $out_fh, $in_fh, $in_offset, $length

=item $retval = aio_readahead $fh,$offset,$length

=item $status = aio_stat $fh_or_path
      
=item $status = aio_lstat $fh

=item $status = aio_unlink $pathname

=item $status = aio_rmdir $pathname

=item $entries = aio_readdir $pathname

=item ($dirs, $nondirs) = aio_scandir $path, $maxreq

=item $status = aio_fsync $fh

=item $status = aio_fdatasync $fh

=item ... = aio_xxx ...

Any additional aio requests follow the same scheme: same parameters except
you must not specify a callback but instead get the callback arguments as
return values.

=back

=head1 SEE ALSO

L<Coro::Socket> and L<Coro::Handle> for non-blocking socket operation.

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

1
Revision:	1.34
Committed:	Sat Dec 13 22:08:13 2008 UTC (15 years, 5 months ago) by root
Branch:	MAIN
CVS Tags:	rel-6_13
Changes since 1.33:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3	root	1.19	Coro::AIO - truly asynchronous file and directory I/O
4	root	1.1
5			=head1 SYNOPSIS
6
7			use Coro::AIO;
8
9	root	1.4	# can now use any of the aio requests your IO::AIO module supports.
10	root	1.1
11			# read 1MB of /etc/passwd, without blocking other coroutines
12			my $fh = aio_open "/etc/passwd", O_RDONLY, 0
13			or die "/etc/passwd: $!";
14			aio_read $fh, 0, 1_000_000, my $buf, 0
15			or die "aio_read: $!";
16			aio_close $fh;
17
18			=head1 DESCRIPTION
19
20	root	1.16	This module is an L<AnyEvent> user, you need to make sure that you use and
21			run a supported event loop.
22
23	root	1.18	This module implements a thin wrapper around L<IO::AIO>. All of
24	root	1.2	the functions that expect a callback are being wrapped by this module.
25	root	1.1
26			The API is exactly the same as that of the corresponding IO::AIO routines,
27			except that you have to specify I<all> arguments I<except> the callback
28			argument. Instead the routines return the values normally passed to the
29	root	1.3	callback. Everything else, including C<$!> and perls stat cache, are set
30			as expected after these functions return.
31	root	1.1
32			You can mix calls to C<IO::AIO> functions with calls to this module. You
33	root	1.3	I<must not>, however, call these routines from within IO::AIO callbacks,
34			as this causes a deadlock. Start a coro inside the callback instead.
35
36	root	1.18	This module also loads L<AnyEvent::AIO> to integrate into the event loop
37			in use, so please refer to its (and L<AnyEvent>'s) documentation on how it
38			selects an appropriate event module.
39	root	1.1
40	root	1.5	All other functions exported by default by IO::AIO (e.g. C<aioreq_pri>)
41			will be exported by default by Coro::AIO, too.
42
43			Functions that can be optionally imported from IO::AIO can be imported
44			from Coro::AIO or can be called directly, e.g. C<Coro::AIO::nreqs>.
45
46	root	1.30	You cannot specify priorities with C<aioreq_pri> if your coroutine has a
47			non-zero priority, as this module overwrites the request priority with the
48			current coroutine priority in that case.
49	root	1.12
50	root	1.30	For your convenience, here are the changed function signatures for most
51	root	1.5	of the requests, for documentation of these functions please have a look
52	root	1.17	at L<IO::AIO\|the IO::AIO manual>. Note that requests added by newer
53			versions of L<IO::AIO> will be automatically wrapped as well.
54	root	1.7
55	root	1.1	=over 4
56
57			=cut
58
59			package Coro::AIO;
60
61	root	1.8	use strict qw(subs vars);
62	root	1.2
63	root	1.22	use IO::AIO 3.1 ();
64			use AnyEvent::AIO ();
65
66	root	1.1	use Coro ();
67	root	1.22	use Coro::AnyEvent ();
68	root	1.1
69			use base Exporter::;
70
71	root	1.34	our $VERSION = 5.13;
72	root	1.20
73	root	1.22	our @EXPORT = (@IO::AIO::EXPORT, qw(aio_wait));
74	root	1.5	our @EXPORT_OK = @IO::AIO::EXPORT_OK;
75			our $AUTOLOAD;
76
77			{
78	root	1.22	my @reqs = @IO::AIO::AIO_REQ ? @IO::AIO::AIO_REQ : @IO::AIO::EXPORT;
79	root	1.5	my %reqs = map +($_ => 1), @reqs;
80
81			eval
82			join "",
83			map "sub $_(" . (prototype "IO::AIO::$_") . ");",
84			grep !$reqs{$_},
85	root	1.22	@IO::AIO::EXPORT, @EXPORT_OK;
86	root	1.1
87	root	1.5	for my $sub (@reqs) {
88			push @EXPORT, $sub;
89	root	1.30
90	root	1.5	my $iosub = "IO::AIO::$sub";
91			my $proto = prototype $iosub;
92	root	1.2
93	root	1.5	$proto =~ s/;?\$$// or die "$iosub: unable to remove callback slot from prototype";
94	root	1.1
95	root	1.30	_register "Coro::AIO::$sub", $proto, \&{$iosub};
96	root	1.5	}
97	root	1.30
98			_register "Coro::AIO::aio_wait", '$', \&IO::AIO::REQ::cb;
99	root	1.1	}
100
101	root	1.5	sub AUTOLOAD {
102			(my $func = $AUTOLOAD) =~ s/^.*:://;
103			*$AUTOLOAD = \&{"IO::AIO::$func"};
104			goto &$AUTOLOAD;
105			}
106	root	1.1
107	root	1.22	=item @results = aio_wait $req
108
109			This is not originally an IO::AIO request: what it does is to wait for
110			C<$req> to finish and return the results. This is most useful with
111			C<aio_group> requests.
112
113	root	1.30	Is currently implemented by replacing the C<$req> callback (and is very
114			much like a wrapper around C<< $req->cb () >>).
115	root	1.22
116	root	1.1	=item $fh = aio_open $pathname, $flags, $mode
117
118			=item $status = aio_close $fh
119
120			=item $retval = aio_read $fh,$offset,$length, $data,$dataoffset
121
122			=item $retval = aio_write $fh,$offset,$length, $data,$dataoffset
123
124			=item $retval = aio_sendfile $out_fh, $in_fh, $in_offset, $length
125
126			=item $retval = aio_readahead $fh,$offset,$length
127
128	root	1.2	=item $status = aio_stat $fh_or_path
129
130			=item $status = aio_lstat $fh
131
132	root	1.1	=item $status = aio_unlink $pathname
133
134			=item $status = aio_rmdir $pathname
135
136	root	1.3	=item $entries = aio_readdir $pathname
137	root	1.1
138			=item ($dirs, $nondirs) = aio_scandir $path, $maxreq
139
140			=item $status = aio_fsync $fh
141
142			=item $status = aio_fdatasync $fh
143
144	root	1.4	=item ... = aio_xxx ...
145
146			Any additional aio requests follow the same scheme: same parameters except
147			you must not specify a callback but instead get the callback arguments as
148			return values.
149
150	root	1.1	=back
151
152	root	1.2	=head1 SEE ALSO
153
154	root	1.4	L<Coro::Socket> and L<Coro::Handle> for non-blocking socket operation.
155	root	1.2
156	root	1.1	=head1 AUTHOR
157
158			Marc Lehmann <schmorp@schmorp.de>
159			http://home.schmorp.de/
160
161			=cut
162
163			1