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=head1 NAME |
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|
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Coro::AIO - truly asynchronous file and directrory I/O |
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|
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=head1 SYNOPSIS |
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|
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use Coro::AIO; |
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|
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# can now use any of |
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# aio_sendfile aio_read aio_write aio_open aio_close aio_stat aio_lstat |
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# aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink aio_fsync |
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# aio_fdatasync aio_readahead |
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|
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# read 1MB of /etc/passwd, without blocking other coroutines |
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my $fh = aio_open "/etc/passwd", O_RDONLY, 0 |
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or die "/etc/passwd: $!"; |
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aio_read $fh, 0, 1_000_000, my $buf, 0 |
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or die "aio_read: $!"; |
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aio_close $fh; |
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|
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=head1 DESCRIPTION |
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|
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This module implements a thin wrapper around L<IO::AIO|IO::AIO>. All of |
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the functions that expect a callback are being wrapped by this module. |
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|
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The API is exactly the same as that of the corresponding IO::AIO routines, |
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except that you have to specify I<all> arguments I<except> the callback |
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argument. Instead the routines return the values normally passed to the |
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callback. Everything else, including C<$!> and perls stat cache, are set |
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as expected after these functions return. |
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|
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You can mix calls to C<IO::AIO> functions with calls to this module. You |
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I<must not>, however, call these routines from within IO::AIO callbacks, |
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as this causes a deadlock. Start a coro inside the callback instead. |
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|
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You also can, but do not need to, call C<IO::AIO::poll_cb>, as this |
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module automatically installs an event watcher for the C<IO::AIO> file |
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descriptor. It uses the L<AnyEvent|AnyEvent> module for this, so please |
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refer to its documentation on how it selects an appropriate Event module. |
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|
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For your convienience, here are the changed function signatures, for |
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documentation of these functions please have a look at L<IO::AIO|the |
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IO::AIO manual>. |
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|
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=over 4 |
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|
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=cut |
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|
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package Coro::AIO; |
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|
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use strict; |
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|
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use Coro (); |
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use AnyEvent; |
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use IO::AIO (); |
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|
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use base Exporter::; |
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|
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our $FH; open $FH, "<&=" . IO::AIO::poll_fileno; |
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our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
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|
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our @EXPORT; |
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|
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sub wrap($) { |
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my ($sub) = @_; |
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|
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no strict 'refs'; |
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|
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push @EXPORT, $sub; |
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|
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my $iosub = "IO::AIO::$sub"; |
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my $proto = prototype $iosub; |
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|
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$proto =~ s/;?\$$// or die "$iosub: unable to remove callback slot from prototype"; |
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|
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eval qq{ |
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#line 1 "Coro::AIO::$sub($proto)" |
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sub $sub($proto) { |
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my \$current = \$Coro::current; |
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my \$stat; |
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my \@res; |
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|
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push \@_, sub { |
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\$stat = Coro::_aio_get_state; |
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\@res = \@_; |
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\$current->ready; |
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undef \$current; |
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}; |
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|
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&$iosub; |
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|
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Coro::schedule while \$current; |
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|
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Coro::_aio_set_state \$stat; |
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wantarray ? \@res : \$res[0] |
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} |
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}; |
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die if $@; |
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} |
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|
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wrap $_ for qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
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aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir |
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aio_symlink aio_fsync aio_fdatasync aio_readahead); |
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|
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=item $fh = aio_open $pathname, $flags, $mode |
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|
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=item $status = aio_close $fh |
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|
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=item $retval = aio_read $fh,$offset,$length, $data,$dataoffset |
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|
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=item $retval = aio_write $fh,$offset,$length, $data,$dataoffset |
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|
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=item $retval = aio_sendfile $out_fh, $in_fh, $in_offset, $length |
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|
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=item $retval = aio_readahead $fh,$offset,$length |
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|
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=item $status = aio_stat $fh_or_path |
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|
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=item $status = aio_lstat $fh |
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|
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=item $status = aio_unlink $pathname |
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|
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=item $status = aio_rmdir $pathname |
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|
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=item $entries = aio_readdir $pathname |
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|
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=item ($dirs, $nondirs) = aio_scandir $path, $maxreq |
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|
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=item $status = aio_fsync $fh |
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|
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=item $status = aio_fdatasync $fh |
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|
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=back |
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|
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=head1 SEE ALSO |
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|
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L<Coro::Socket> and L<Coro::Handle> for non-blocking file operation. |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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|
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=cut |
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1 |