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/cvs/Coro/Coro/AIO.pm
Revision: 1.3
Committed: Mon Dec 26 21:54:44 2005 UTC (19 years, 1 month ago) by root
Branch: MAIN
CVS Tags: rel-1_9, rel-1_7
Changes since 1.2: +32 -21 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 =head1 NAME
2
3 Coro::AIO - truly asynchronous file and directrory I/O
4
5 =head1 SYNOPSIS
6
7 use Coro::AIO;
8
9 # can now use any of
10 # aio_sendfile aio_read aio_write aio_open aio_close aio_stat aio_lstat
11 # aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink aio_fsync
12 # aio_fdatasync aio_readahead
13
14 # read 1MB of /etc/passwd, without blocking other coroutines
15 my $fh = aio_open "/etc/passwd", O_RDONLY, 0
16 or die "/etc/passwd: $!";
17 aio_read $fh, 0, 1_000_000, my $buf, 0
18 or die "aio_read: $!";
19 aio_close $fh;
20
21 =head1 DESCRIPTION
22
23 This module implements a thin wrapper around L<IO::AIO|IO::AIO>. All of
24 the functions that expect a callback are being wrapped by this module.
25
26 The API is exactly the same as that of the corresponding IO::AIO routines,
27 except that you have to specify I<all> arguments I<except> the callback
28 argument. Instead the routines return the values normally passed to the
29 callback. Everything else, including C<$!> and perls stat cache, are set
30 as expected after these functions return.
31
32 You can mix calls to C<IO::AIO> functions with calls to this module. You
33 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 You also can, but do not need to, call C<IO::AIO::poll_cb>, as this
37 module automatically installs an event watcher for the C<IO::AIO> file
38 descriptor. It uses the L<AnyEvent|AnyEvent> module for this, so please
39 refer to its documentation on how it selects an appropriate Event module.
40
41 For your convienience, here are the changed function signatures, for
42 documentation of these functions please have a look at L<IO::AIO|the
43 IO::AIO manual>.
44
45 =over 4
46
47 =cut
48
49 package Coro::AIO;
50
51 use strict;
52
53 use Coro ();
54 use AnyEvent;
55 use IO::AIO ();
56
57 use base Exporter::;
58
59 our $FH; open $FH, "<&=" . IO::AIO::poll_fileno;
60 our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => sub { IO::AIO::poll_cb });
61
62 our @EXPORT;
63
64 sub wrap($) {
65 my ($sub) = @_;
66
67 no strict 'refs';
68
69 push @EXPORT, $sub;
70
71 my $iosub = "IO::AIO::$sub";
72 my $proto = prototype $iosub;
73
74 $proto =~ s/;?\$$// or die "$iosub: unable to remove callback slot from prototype";
75
76 eval qq{
77 #line 1 "Coro::AIO::$sub($proto)"
78 sub $sub($proto) {
79 my \$current = \$Coro::current;
80 my \$stat;
81 my \@res;
82
83 push \@_, sub {
84 \$stat = Coro::_aio_get_state;
85 \@res = \@_;
86 \$current->ready;
87 undef \$current;
88 };
89
90 &$iosub;
91
92 Coro::schedule while \$current;
93
94 Coro::_aio_set_state \$stat;
95 wantarray ? \@res : \$res[0]
96 }
97 };
98 die if $@;
99 }
100
101 wrap $_ for qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat
102 aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir
103 aio_symlink aio_fsync aio_fdatasync aio_readahead);
104
105 =item $fh = aio_open $pathname, $flags, $mode
106
107 =item $status = aio_close $fh
108
109 =item $retval = aio_read $fh,$offset,$length, $data,$dataoffset
110
111 =item $retval = aio_write $fh,$offset,$length, $data,$dataoffset
112
113 =item $retval = aio_sendfile $out_fh, $in_fh, $in_offset, $length
114
115 =item $retval = aio_readahead $fh,$offset,$length
116
117 =item $status = aio_stat $fh_or_path
118
119 =item $status = aio_lstat $fh
120
121 =item $status = aio_unlink $pathname
122
123 =item $status = aio_rmdir $pathname
124
125 =item $entries = aio_readdir $pathname
126
127 =item ($dirs, $nondirs) = aio_scandir $path, $maxreq
128
129 =item $status = aio_fsync $fh
130
131 =item $status = aio_fdatasync $fh
132
133 =back
134
135 =head1 SEE ALSO
136
137 L<Coro::Socket> and L<Coro::Handle> for non-blocking file operation.
138
139 =head1 AUTHOR
140
141 Marc Lehmann <schmorp@schmorp.de>
142 http://home.schmorp.de/
143
144 =cut
145
146 1