[ViewVC] Diff of: cvs/IO-AIO/AIO.pm

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.37 by root, Tue Aug 23 12:37:19 2005 UTC vs.
Revision 1.52 by root, Sat Oct 21 23:06:04 2006 UTC

…		…
14	aio_unlink "/tmp/file", sub { };	14	aio_unlink "/tmp/file", sub { };
15		15
16	aio_read $fh, 30000, 1024, $buffer, 0, sub {	16	aio_read $fh, 30000, 1024, $buffer, 0, sub {
17	$_[0] > 0 or die "read error: $!";	17	$_[0] > 0 or die "read error: $!";
18	};	18	};
		19
		20	use IO::AIO 2; # version has aio objects
		21
		22	my $req = aio_unlink "/tmp/file", sub { };
		23	$req->cancel; # cancel request if still in queue
		24
		25	# AnyEvent
		26	open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
		27	my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
19		28
20	# Event	29	# Event
21	Event->io (fd => IO::AIO::poll_fileno,	30	Event->io (fd => IO::AIO::poll_fileno,
22	poll => 'r',	31	poll => 'r',
23	cb => \&IO::AIO::poll_cb);	32	cb => \&IO::AIO::poll_cb);
…		…
57	=cut	66	=cut
58		67
59	package IO::AIO;	68	package IO::AIO;
60		69
61	no warnings;	70	no warnings;
		71	use strict 'vars';
62		72
63	use base 'Exporter';	73	use base 'Exporter';
64		74
65	use Fcntl ();
66
67	BEGIN {	75	BEGIN {
68	$VERSION = 1.6;	76	our $VERSION = '1.8';
69		77
70	@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink	78	our @EXPORT = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat
71	aio_rmdir aio_readdir aio_symlink aio_fsync aio_fdatasync aio_readahead);	79	aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink
		80	aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move);
72	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);	81	our @EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);
73		82
74	require XSLoader;	83	require XSLoader;
75	XSLoader::load IO::AIO, $VERSION;	84	XSLoader::load ("IO::AIO", $VERSION);
76	}	85	}
77		86
78	=head1 FUNCTIONS	87	=head1 FUNCTIONS
79		88
80	=head2 AIO FUNCTIONS	89	=head2 AIO FUNCTIONS
…		…
88	syscall has been executed asynchronously.	97	syscall has been executed asynchronously.
89		98
90	All functions expecting a filehandle keep a copy of the filehandle	99	All functions expecting a filehandle keep a copy of the filehandle
91	internally until the request has finished.	100	internally until the request has finished.
92		101
		102	All non-composite requests (requests that are not broken down into
		103	multiple requests) return objects of type L<IO::AIO::REQ> that allow
		104	further manipulation of running requests.
		105
93	The pathnames you pass to these routines I<must> be absolute and	106	The pathnames you pass to these routines I<must> be absolute and
94	encoded in byte form. The reason for the former is that at the time the	107	encoded in byte form. The reason for the former is that at the time the
95	request is being executed, the current working directory could have	108	request is being executed, the current working directory could have
96	changed. Alternatively, you can make sure that you never change the	109	changed. Alternatively, you can make sure that you never change the
97	current working directory.	110	current working directory.
…		…
103	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	116	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
104	use something else.	117	use something else.
105		118
106	=over 4	119	=over 4
107		120
108	=item aio_open $pathname, $flags, $mode, $callback	121	=item aio_open $pathname, $flags, $mode, $callback->($fh)
109		122
110	Asynchronously open or create a file and call the callback with a newly	123	Asynchronously open or create a file and call the callback with a newly
111	created filehandle for the file.	124	created filehandle for the file.
112		125
113	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	126	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
…		…
130	} else {	143	} else {
131	die "open failed: $!\n";	144	die "open failed: $!\n";
132	}	145	}
133	};	146	};
134		147
135	=item aio_close $fh, $callback	148	=item aio_close $fh, $callback->($status)
136		149
137	Asynchronously close a file and call the callback with the result	150	Asynchronously close a file and call the callback with the result
138	code. I<WARNING:> although accepted, you should not pass in a perl	151	code. I<WARNING:> although accepted, you should not pass in a perl
139	filehandle here, as perl will likely close the file descriptor another	152	filehandle here, as perl will likely close the file descriptor another
140	time when the filehandle is destroyed. Normally, you can safely call perls	153	time when the filehandle is destroyed. Normally, you can safely call perls
141	C<close> or just let filehandles go out of scope.	154	C<close> or just let filehandles go out of scope.
142		155
143	This is supposed to be a bug in the API, so that might change. It's	156	This is supposed to be a bug in the API, so that might change. It's
144	therefore best to avoid this function.	157	therefore best to avoid this function.
145		158
146	=item aio_read $fh,$offset,$length, $data,$dataoffset,$callback	159	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
147		160
148	=item aio_write $fh,$offset,$length, $data,$dataoffset,$callback	161	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
149		162
150	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	163	Reads or writes C<length> bytes from the specified C<fh> and C<offset>
151	into the scalar given by C<data> and offset C<dataoffset> and calls the	164	into the scalar given by C<data> and offset C<dataoffset> and calls the
152	callback without the actual number of bytes read (or -1 on error, just	165	callback without the actual number of bytes read (or -1 on error, just
153	like the syscall).	166	like the syscall).
…		…
162	aio_read $fh, 7, 15, $buffer, 0, sub {	175	aio_read $fh, 7, 15, $buffer, 0, sub {
163	$_[0] > 0 or die "read error: $!";	176	$_[0] > 0 or die "read error: $!";
164	print "read $_[0] bytes: <$buffer>\n";	177	print "read $_[0] bytes: <$buffer>\n";
165	};	178	};
166		179
		180	=item aio_move $srcpath, $dstpath, $callback->($status)
		181
		182	Try to move the I<file> (directories not supported as either source or
		183	destination) from C<$srcpath> to C<$dstpath> and call the callback with
		184	the C<0> (error) or C<-1> ok.
		185
		186	This is a composite request that tries to rename(2) the file first. If
		187	rename files with C<EXDEV>, it creates the destination file with mode 0200
		188	and copies the contents of the source file into it using C<aio_sendfile>,
		189	followed by restoring atime, mtime, access mode and uid/gid, in that
		190	order, and unlinking the C<$srcpath>.
		191
		192	If an error occurs, the partial destination file will be unlinked, if
		193	possible, except when setting atime, mtime, access mode and uid/gid, where
		194	errors are being ignored.
		195
		196	=cut
		197
		198	sub aio_move($$$) {
		199	my ($src, $dst, $cb) = @_;
		200
		201	aio_rename $src, $dst, sub {
		202	if ($_[0] && $! == EXDEV) {
		203	aio_open $src, O_RDONLY, 0, sub {
		204	if (my $src_fh = $_[0]) {
		205	my @stat = stat $src_fh;
		206
		207	aio_open $dst, O_WRONLY, 0200, sub {
		208	if (my $dst_fh = $_[0]) {
		209	aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
		210	close $src_fh;
		211
		212	if ($_[0] == $stat[7]) {
		213	utime $stat[8], $stat[9], $dst;
		214	chmod $stat[2] & 07777, $dst_fh;
		215	chown $stat[4], $stat[5], $dst_fh;
		216	close $dst_fh;
		217
		218	aio_unlink $src, sub {
		219	$cb->($_[0]);
		220	};
		221	} else {
		222	my $errno = $!;
		223	aio_unlink $dst, sub {
		224	$! = $errno;
		225	$cb->(-1);
		226	};
		227	}
		228	};
		229	} else {
		230	$cb->(-1);
		231	}
		232	},
		233
		234	} else {
		235	$cb->(-1);
		236	}
		237	};
		238	} else {
		239	$cb->($_[0]);
		240	}
		241	};
		242	}
		243
167	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback	244	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
168		245
169	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts	246	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
170	reading at byte offset C<$in_offset>, and starts writing at the current	247	reading at byte offset C<$in_offset>, and starts writing at the current
171	file offset of C<$out_fh>. Because of that, it is not safe to issue more	248	file offset of C<$out_fh>. Because of that, it is not safe to issue more
172	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each	249	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
…		…
185	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	262	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
186	provides the number of bytes written to C<$out_fh>. Only if the result	263	provides the number of bytes written to C<$out_fh>. Only if the result
187	value equals C<$length> one can assume that C<$length> bytes have been	264	value equals C<$length> one can assume that C<$length> bytes have been
188	read.	265	read.
189		266
190	=item aio_readahead $fh,$offset,$length, $callback	267	=item aio_readahead $fh,$offset,$length, $callback->($retval)
191		268
192	C<aio_readahead> populates the page cache with data from a file so that	269	C<aio_readahead> populates the page cache with data from a file so that
193	subsequent reads from that file will not block on disk I/O. The C<$offset>	270	subsequent reads from that file will not block on disk I/O. The C<$offset>
194	argument specifies the starting point from which data is to be read and	271	argument specifies the starting point from which data is to be read and
195	C<$length> specifies the number of bytes to be read. I/O is performed in	272	C<$length> specifies the number of bytes to be read. I/O is performed in
…		…
199	file. The current file offset of the file is left unchanged.	276	file. The current file offset of the file is left unchanged.
200		277
201	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	278	If that syscall doesn't exist (likely if your OS isn't Linux) it will be
202	emulated by simply reading the data, which would have a similar effect.	279	emulated by simply reading the data, which would have a similar effect.
203		280
204	=item aio_stat $fh_or_path, $callback	281	=item aio_stat $fh_or_path, $callback->($status)
205		282
206	=item aio_lstat $fh, $callback	283	=item aio_lstat $fh, $callback->($status)
207		284
208	Works like perl's C<stat> or C<lstat> in void context. The callback will	285	Works like perl's C<stat> or C<lstat> in void context. The callback will
209	be called after the stat and the results will be available using C<stat _>	286	be called after the stat and the results will be available using C<stat _>
210	or C<-s _> etc...	287	or C<-s _> etc...
211		288
…		…
221	aio_stat "/etc/passwd", sub {	298	aio_stat "/etc/passwd", sub {
222	$_[0] and die "stat failed: $!";	299	$_[0] and die "stat failed: $!";
223	print "size is ", -s _, "\n";	300	print "size is ", -s _, "\n";
224	};	301	};
225		302
226	=item aio_unlink $pathname, $callback	303	=item aio_unlink $pathname, $callback->($status)
227		304
228	Asynchronously unlink (delete) a file and call the callback with the	305	Asynchronously unlink (delete) a file and call the callback with the
229	result code.	306	result code.
230		307
		308	=item aio_link $srcpath, $dstpath, $callback->($status)
		309
		310	Asynchronously create a new link to the existing object at C<$srcpath> at
		311	the path C<$dstpath> and call the callback with the result code.
		312
		313	=item aio_symlink $srcpath, $dstpath, $callback->($status)
		314
		315	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
		316	the path C<$dstpath> and call the callback with the result code.
		317
		318	=item aio_rename $srcpath, $dstpath, $callback->($status)
		319
		320	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
		321	rename(2) and call the callback with the result code.
		322
231	=item aio_rmdir $pathname, $callback	323	=item aio_rmdir $pathname, $callback->($status)
232		324
233	Asynchronously rmdir (delete) a directory and call the callback with the	325	Asynchronously rmdir (delete) a directory and call the callback with the
234	result code.	326	result code.
235		327
236	=item aio_readdir $pathname $callback	328	=item aio_readdir $pathname, $callback->($entries)
237		329
238	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	330	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
239	directory (i.e. opendir + readdir + closedir). The entries will not be	331	directory (i.e. opendir + readdir + closedir). The entries will not be
240	sorted, and will B<NOT> include the C<.> and C<..> entries.	332	sorted, and will B<NOT> include the C<.> and C<..> entries.
241		333
242	The callback a single argument which is either C<undef> or an array-ref	334	The callback a single argument which is either C<undef> or an array-ref
243	with the filenames.	335	with the filenames.
244		336
		337	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
		338
		339	Scans a directory (similar to C<aio_readdir>) but additionally tries to
		340	separate the entries of directory C<$path> into two sets of names, ones
		341	you can recurse into (directories or links to them), and ones you cannot
		342	recurse into (everything else).
		343
		344	C<aio_scandir> is a composite request that consists of many sub
		345	requests. C<$maxreq> specifies the maximum number of outstanding aio
		346	requests that this function generates. If it is C<< <= 0 >>, then a
		347	suitable default will be chosen (currently 8).
		348
		349	On error, the callback is called without arguments, otherwise it receives
		350	two array-refs with path-relative entry names.
		351
		352	Example:
		353
		354	aio_scandir $dir, 0, sub {
		355	my ($dirs, $nondirs) = @_;
		356	print "real directories: @$dirs\n";
		357	print "everything else: @$nondirs\n";
		358	};
		359
		360	Implementation notes.
		361
		362	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
		363
		364	After reading the directory, the modification time, size etc. of the
		365	directory before and after the readdir is checked, and if they match (and
		366	isn't the current time), the link count will be used to decide how many
		367	entries are directories (if >= 2). Otherwise, no knowledge of the number
		368	of subdirectories will be assumed.
		369
		370	Then entries will be sorted into likely directories (everything without
		371	a non-initial dot currently) and likely non-directories (everything
		372	else). Then every entry plus an appended C</.> will be C<stat>'ed,
		373	likely directories first. If that succeeds, it assumes that the entry
		374	is a directory or a symlink to directory (which will be checked
		375	seperately). This is often faster than stat'ing the entry itself because
		376	filesystems might detect the type of the entry without reading the inode
		377	data (e.g. ext2fs filetype feature).
		378
		379	If the known number of directories (link count - 2) has been reached, the
		380	rest of the entries is assumed to be non-directories.
		381
		382	This only works with certainty on POSIX (= UNIX) filesystems, which
		383	fortunately are the vast majority of filesystems around.
		384
		385	It will also likely work on non-POSIX filesystems with reduced efficiency
		386	as those tend to return 0 or 1 as link counts, which disables the
		387	directory counting heuristic.
		388
		389	=cut
		390
		391	sub aio_scandir($$$) {
		392	my ($path, $maxreq, $cb) = @_;
		393
		394	$maxreq = 8 if $maxreq <= 0;
		395
		396	# stat once
		397	aio_stat $path, sub {
		398	return $cb->() if $_[0];
		399	my $now = time;
		400	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		401
		402	# read the directory entries
		403	aio_readdir $path, sub {
		404	my $entries = shift
		405	or return $cb->();
		406
		407	# stat the dir another time
		408	aio_stat $path, sub {
		409	my $hash2 = join ":", (stat _)[0,1,3,7,9];
		410
		411	my $ndirs;
		412
		413	# take the slow route if anything looks fishy
		414	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
		415	$ndirs = -1;
		416	} else {
		417	# if nlink == 2, we are finished
		418	# on non-posix-fs's, we rely on nlink < 2
		419	$ndirs = (stat _)[3] - 2
		420	or return $cb->([], $entries);
		421	}
		422
		423	# sort into likely dirs and likely nondirs
		424	# dirs == files without ".", short entries first
		425	$entries = [map $_->[0],
		426	sort { $b->[1] cmp $a->[1] }
		427	map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
		428	@$entries];
		429
		430	my (@dirs, @nondirs);
		431
		432	my ($statcb, $schedcb);
		433	my $nreq = 0;
		434
		435	$schedcb = sub {
		436	if (@$entries) {
		437	if ($nreq < $maxreq) {
		438	my $ent = pop @$entries;
		439	$nreq++;
		440	aio_stat "$path/$ent/.", sub { $statcb->($_[0], $ent) };
		441	}
		442	} elsif (!$nreq) {
		443	# finished
		444	undef $statcb;
		445	undef $schedcb;
		446	$cb->(\@dirs, \@nondirs) if $cb;
		447	undef $cb;
		448	}
		449	};
		450	$statcb = sub {
		451	my ($status, $entry) = @_;
		452
		453	if ($status < 0) {
		454	$nreq--;
		455	push @nondirs, $entry;
		456	&$schedcb;
		457	} else {
		458	# need to check for real directory
		459	aio_lstat "$path/$entry", sub {
		460	$nreq--;
		461
		462	if (-d _) {
		463	push @dirs, $entry;
		464
		465	if (!--$ndirs) {
		466	push @nondirs, @$entries;
		467	$entries = [];
		468	}
		469	} else {
		470	push @nondirs, $entry;
		471	}
		472
		473	&$schedcb;
		474	}
		475	}
		476	};
		477
		478	&$schedcb while @$entries && $nreq < $maxreq;
		479	};
		480	};
		481	};
		482	}
		483
245	=item aio_fsync $fh, $callback	484	=item aio_fsync $fh, $callback->($status)
246		485
247	Asynchronously call fsync on the given filehandle and call the callback	486	Asynchronously call fsync on the given filehandle and call the callback
248	with the fsync result code.	487	with the fsync result code.
249		488
250	=item aio_fdatasync $fh, $callback	489	=item aio_fdatasync $fh, $callback->($status)
251		490
252	Asynchronously call fdatasync on the given filehandle and call the	491	Asynchronously call fdatasync on the given filehandle and call the
253	callback with the fdatasync result code.	492	callback with the fdatasync result code.
254		493
255	If this call isn't available because your OS lacks it or it couldn't be	494	If this call isn't available because your OS lacks it or it couldn't be
256	detected, it will be emulated by calling C<fsync> instead.	495	detected, it will be emulated by calling C<fsync> instead.
		496
		497	=back
		498
		499	=head2 IO::AIO::CB CLASS
		500
		501	All non-aggregate C<aio_*> functions return an object of this class when
		502	called in non-void context.
		503
		504	A request always moves through the following five states in its lifetime,
		505	in order: B<ready> (request has been created, but has not been executed
		506	yet), B<execute> (request is currently being executed), B<pending>
		507	(request has been executed but callback has not been called yet),
		508	B<result> (results are being processed synchronously, includes calling the
		509	callback) and B<done> (request has reached the end of its lifetime and
		510	holds no resources anymore).
		511
		512	=over 4
		513
		514	=item $req->cancel
		515
		516	Cancels the request, if possible. Has the effect of skipping execution
		517	when entering the B<execute> state and skipping calling the callback when
		518	entering the the B<result> state, but will leave the request otherwise
		519	untouched. That means that requests that currently execute will not be
		520	stopped and resources held by the request will not be freed prematurely.
257		521
258	=back	522	=back
259		523
260	=head2 SUPPORT FUNCTIONS	524	=head2 SUPPORT FUNCTIONS
261		525
…		…
389	}	653	}
390		654
391	1;	655	1;
392		656
393	=head2 FORK BEHAVIOUR	657	=head2 FORK BEHAVIOUR
		658
		659	This module should do "the right thing" when the process using it forks:
394		660
395	Before the fork, IO::AIO enters a quiescent state where no requests	661	Before the fork, IO::AIO enters a quiescent state where no requests
396	can be added in other threads and no results will be processed. After	662	can be added in other threads and no results will be processed. After
397	the fork the parent simply leaves the quiescent state and continues	663	the fork the parent simply leaves the quiescent state and continues
398	request/result processing, while the child clears the request/result	664	request/result processing, while the child clears the request/result
399	queue (so the requests started before the fork will only be handled in	665	queue (so the requests started before the fork will only be handled in
400	the parent). Threats will be started on demand until the limit ste in the	666	the parent). Threads will be started on demand until the limit ste in the
401	parent process has been reached again.	667	parent process has been reached again.
402		668
		669	In short: the parent will, after a short pause, continue as if fork had
		670	not been called, while the child will act as if IO::AIO has not been used
		671	yet.
		672
403	=head1 SEE ALSO	673	=head1 SEE ALSO
404		674
405	L<Coro>, L<Linux::AIO>.	675	L<Coro>, L<Linux::AIO> (obsolete).
406		676
407	=head1 AUTHOR	677	=head1 AUTHOR
408		678
409	Marc Lehmann <schmorp@schmorp.de>	679	Marc Lehmann <schmorp@schmorp.de>
410	http://home.schmorp.de/	680	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.37 by root, Tue Aug 23 12:37:19 2005 UTC vs. Revision 1.52 by root, Sat Oct 21 23:06:04 2006 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.37 by root, Tue Aug 23 12:37:19 2005 UTC vs.
Revision 1.52 by root, Sat Oct 21 23:06:04 2006 UTC