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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.50 by root, Sat Jun 24 16:27:02 2006 UTC vs.
Revision 1.57 by root, Sun Oct 22 01:28:31 2006 UTC

…		…
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		19
20	# AnyEvent	20	# version 2+ has request and group objects
		21	use IO::AIO 2;
		22
		23	my $req = aio_unlink "/tmp/file", sub { };
		24	$req->cancel; # cancel request if still in queue
		25
		26	my $grp = aio_group sub { print "all stats done\n" };
		27	add $grp aio_stat "..." for ...;
		28
		29	# AnyEvent integration
21	open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";	30	open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
22	my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });	31	my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
23		32
24	# Event	33	# Event integration
25	Event->io (fd => IO::AIO::poll_fileno,	34	Event->io (fd => IO::AIO::poll_fileno,
26	poll => 'r',	35	poll => 'r',
27	cb => \&IO::AIO::poll_cb);	36	cb => \&IO::AIO::poll_cb);
28		37
29	# Glib/Gtk2	38	# Glib/Gtk2 integration
30	add_watch Glib::IO IO::AIO::poll_fileno,	39	add_watch Glib::IO IO::AIO::poll_fileno,
31	in => sub { IO::AIO::poll_cb; 1 };	40	in => sub { IO::AIO::poll_cb; 1 };
32		41
33	# Tk	42	# Tk integration
34	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",	43	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
35	readable => \&IO::AIO::poll_cb);	44	readable => \&IO::AIO::poll_cb);
36		45
37	# Danga::Socket	46	# Danga::Socket integration
38	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>	47	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
39	\&IO::AIO::poll_cb);	48	\&IO::AIO::poll_cb);
40
41		49
42	=head1 DESCRIPTION	50	=head1 DESCRIPTION
43		51
44	This module implements asynchronous I/O using whatever means your	52	This module implements asynchronous I/O using whatever means your
45	operating system supports.	53	operating system supports.
…		…
61	=cut	69	=cut
62		70
63	package IO::AIO;	71	package IO::AIO;
64		72
65	no warnings;	73	no warnings;
		74	use strict 'vars';
66		75
67	use base 'Exporter';	76	use base 'Exporter';
68		77
69	use Fcntl ();
70
71	BEGIN {	78	BEGIN {
72	$VERSION = '1.8';	79	our $VERSION = '2.0';
73		80
74	@EXPORT = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat	81	our @EXPORT = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat
75	aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink	82	aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink
76	aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move);	83	aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move
		84	aio_group);
77	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel	85	our @EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);
78	max_outstanding nreqs);	86
		87	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
79		88
80	require XSLoader;	89	require XSLoader;
81	XSLoader::load IO::AIO, $VERSION;	90	XSLoader::load ("IO::AIO", $VERSION);
82	}	91	}
83		92
84	=head1 FUNCTIONS	93	=head1 FUNCTIONS
85		94
86	=head2 AIO FUNCTIONS	95	=head2 AIO FUNCTIONS
…		…
93	perl, which usually delivers "false") as it's sole argument when the given	102	perl, which usually delivers "false") as it's sole argument when the given
94	syscall has been executed asynchronously.	103	syscall has been executed asynchronously.
95		104
96	All functions expecting a filehandle keep a copy of the filehandle	105	All functions expecting a filehandle keep a copy of the filehandle
97	internally until the request has finished.	106	internally until the request has finished.
		107
		108	All requests return objects of type L<IO::AIO::REQ> that allow further
		109	manipulation of those requests while they are in-flight.
98		110
99	The pathnames you pass to these routines I<must> be absolute and	111	The pathnames you pass to these routines I<must> be absolute and
100	encoded in byte form. The reason for the former is that at the time the	112	encoded in byte form. The reason for the former is that at the time the
101	request is being executed, the current working directory could have	113	request is being executed, the current working directory could have
102	changed. Alternatively, you can make sure that you never change the	114	changed. Alternatively, you can make sure that you never change the
…		…
170	print "read $_[0] bytes: <$buffer>\n";	182	print "read $_[0] bytes: <$buffer>\n";
171	};	183	};
172		184
173	=item aio_move $srcpath, $dstpath, $callback->($status)	185	=item aio_move $srcpath, $dstpath, $callback->($status)
174		186
175	[EXPERIMENTAL]
176
177	Try to move the I<file> (directories not supported as either source or destination)	187	Try to move the I<file> (directories not supported as either source or
178	from C<$srcpath> to C<$dstpath> and call the callback with the C<0> (error) or C<-1> ok.	188	destination) from C<$srcpath> to C<$dstpath> and call the callback with
		189	the C<0> (error) or C<-1> ok.
179		190
180	This is a composite request that tries to rename(2) the file first. If	191	This is a composite request that tries to rename(2) the file first. If
181	rename files with C<EXDEV>, it creates the destination file with mode 0200	192	rename files with C<EXDEV>, it creates the destination file with mode 0200
182	and copies the contents of the source file into it using C<aio_sendfile>,	193	and copies the contents of the source file into it using C<aio_sendfile>,
183	followed by restoring atime, mtime, access mode and uid/gid, in that	194	followed by restoring atime, mtime, access mode and uid/gid, in that
…		…
190	=cut	201	=cut
191		202
192	sub aio_move($$$) {	203	sub aio_move($$$) {
193	my ($src, $dst, $cb) = @_;	204	my ($src, $dst, $cb) = @_;
194		205
		206	my $grp = aio_group;
		207
195	aio_rename $src, $dst, sub {	208	add $grp aio_rename $src, $dst, sub {
196	if ($_[0] && $! == Errno::EXDEV) {	209	if ($_[0] && $! == EXDEV) {
197	aio_open $src, O_RDONLY, 0, sub {	210	add $grp aio_open $src, O_RDONLY, 0, sub {
198	if (my $src_fh = $_[0]) {	211	if (my $src_fh = $_[0]) {
199	my @stat = stat $src_fh;	212	my @stat = stat $src_fh;
200		213
201	aio_open $dst, O_WRONLY, 0200, sub {	214	add $grp aio_open $dst, O_WRONLY, 0200, sub {
202	if (my $dst_fh = $_[0]) {	215	if (my $dst_fh = $_[0]) {
203	aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {	216	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
204	close $src_fh;	217	close $src_fh;
205		218
206	if ($_[0] == $stat[7]) {	219	if ($_[0] == $stat[7]) {
207	utime $stat[8], $stat[9], $dst;	220	utime $stat[8], $stat[9], $dst;
208	chmod $stat[2] & 07777, $dst_fh;	221	chmod $stat[2] & 07777, $dst_fh;
209	chown $stat[4], $stat[5], $dst_fh;	222	chown $stat[4], $stat[5], $dst_fh;
210	close $dst_fh;	223	close $dst_fh;
211		224
212	aio_unlink $src, sub {	225	add $grp aio_unlink $src, sub {
213	$cb->($_[0]);	226	$cb->($_[0]);
214	};	227	};
215	} else {	228	} else {
216	my $errno = $!;	229	my $errno = $!;
217	aio_unlink $dst, sub {	230	add $grp aio_unlink $dst, sub {
218	$! = $errno;	231	$! = $errno;
219	$cb->(-1);	232	$cb->(-1);
220	};	233	};
221	}	234	}
222	};	235	};
…		…
231	};	244	};
232	} else {	245	} else {
233	$cb->($_[0]);	246	$cb->($_[0]);
234	}	247	}
235	};	248	};
		249
		250	$grp
236	}	251	}
237		252
238	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	253	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
239		254
240	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts	255	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
…		…
328	The callback a single argument which is either C<undef> or an array-ref	343	The callback a single argument which is either C<undef> or an array-ref
329	with the filenames.	344	with the filenames.
330		345
331	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	346	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
332		347
333	Scans a directory (similar to C<aio_readdir>) and tries to separate the	348	Scans a directory (similar to C<aio_readdir>) but additionally tries to
334	entries of directory C<$path> into two sets of names, ones you can recurse	349	separate the entries of directory C<$path> into two sets of names, ones
335	into (directories), and ones you cannot recurse into (everything else).	350	you can recurse into (directories or links to them), and ones you cannot
		351	recurse into (everything else).
336		352
337	C<aio_scandir> is a composite request that consists of many	353	C<aio_scandir> is a composite request that consists of many sub
338	aio-primitives. C<$maxreq> specifies the maximum number of outstanding	354	requests. C<$maxreq> specifies the maximum number of outstanding aio
339	aio requests that this function generates. If it is C<< <= 0 >>, then a	355	requests that this function generates. If it is C<< <= 0 >>, then a
340	suitable default will be chosen (currently 8).	356	suitable default will be chosen (currently 8).
341		357
342	On error, the callback is called without arguments, otherwise it receives	358	On error, the callback is called without arguments, otherwise it receives
343	two array-refs with path-relative entry names.	359	two array-refs with path-relative entry names.
344		360
…		…
353	Implementation notes.	369	Implementation notes.
354		370
355	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.	371	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
356		372
357	After reading the directory, the modification time, size etc. of the	373	After reading the directory, the modification time, size etc. of the
358	directory before and after the readdir is checked, and if they match, the	374	directory before and after the readdir is checked, and if they match (and
359	link count will be used to decide how many entries are directories (if	375	isn't the current time), the link count will be used to decide how many
360	>= 2). Otherwise, no knowledge of the number of subdirectories will be	376	entries are directories (if >= 2). Otherwise, no knowledge of the number
361	assumed.	377	of subdirectories will be assumed.
362		378
363	Then entires will be sorted into likely directories (everything without a	379	Then entries will be sorted into likely directories (everything without
364	non-initial dot) and likely non-directories (everything else). Then every	380	a non-initial dot currently) and likely non-directories (everything
365	entry + C</.> will be C<stat>'ed, likely directories first. This is often	381	else). Then every entry plus an appended C</.> will be C<stat>'ed,
		382	likely directories first. If that succeeds, it assumes that the entry
		383	is a directory or a symlink to directory (which will be checked
		384	seperately). This is often faster than stat'ing the entry itself because
366	faster because filesystems might detect the type of the entry without	385	filesystems might detect the type of the entry without reading the inode
367	reading the inode data (e.g. ext2fs filetype feature). If that succeeds,	386	data (e.g. ext2fs filetype feature).
368	it assumes that the entry is a directory or a symlink to directory (which
369	will be checked seperately).
370		387
371	If the known number of directories has been reached, the rest of the	388	If the known number of directories (link count - 2) has been reached, the
372	entries is assumed to be non-directories.	389	rest of the entries is assumed to be non-directories.
		390
		391	This only works with certainty on POSIX (= UNIX) filesystems, which
		392	fortunately are the vast majority of filesystems around.
		393
		394	It will also likely work on non-POSIX filesystems with reduced efficiency
		395	as those tend to return 0 or 1 as link counts, which disables the
		396	directory counting heuristic.
373		397
374	=cut	398	=cut
375		399
376	sub aio_scandir($$$) {	400	sub aio_scandir($$$) {
377	my ($path, $maxreq, $cb) = @_;	401	my ($path, $maxreq, $cb) = @_;
378		402
		403	my $grp = aio_group;
		404
379	$maxreq = 8 if $maxreq <= 0;	405	$maxreq = 8 if $maxreq <= 0;
380		406
381	# stat once	407	# stat once
382	aio_stat $path, sub {	408	add $grp aio_stat $path, sub {
383	return $cb->() if $_[0];	409	return $cb->() if $_[0];
		410	my $now = time;
384	my $hash1 = join ":", (stat _)[0,1,3,7,9];	411	my $hash1 = join ":", (stat _)[0,1,3,7,9];
385		412
386	# read the directory entries	413	# read the directory entries
387	aio_readdir $path, sub {	414	add $grp aio_readdir $path, sub {
388	my $entries = shift	415	my $entries = shift
389	or return $cb->();	416	or return $cb->();
390		417
391	# stat the dir another time	418	# stat the dir another time
392	aio_stat $path, sub {	419	add $grp aio_stat $path, sub {
393	my $hash2 = join ":", (stat _)[0,1,3,7,9];	420	my $hash2 = join ":", (stat _)[0,1,3,7,9];
394		421
395	my $ndirs;	422	my $ndirs;
396		423
397	# take the slow route if anything looks fishy	424	# take the slow route if anything looks fishy
398	if ($hash1 ne $hash2) {	425	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
399	$ndirs = -1;	426	$ndirs = -1;
400	} else {	427	} else {
401	# if nlink == 2, we are finished	428	# if nlink == 2, we are finished
402	# on non-posix-fs's, we rely on nlink < 2	429	# on non-posix-fs's, we rely on nlink < 2
403	$ndirs = (stat _)[3] - 2	430	$ndirs = (stat _)[3] - 2
…		…
419	$schedcb = sub {	446	$schedcb = sub {
420	if (@$entries) {	447	if (@$entries) {
421	if ($nreq < $maxreq) {	448	if ($nreq < $maxreq) {
422	my $ent = pop @$entries;	449	my $ent = pop @$entries;
423	$nreq++;	450	$nreq++;
424	aio_stat "$path/$ent/.", sub { $statcb->($_[0], $ent) };	451	add $grp aio_stat "$path/$ent/.", sub { $statcb->($_[0], $ent) };
425	}	452	}
426	} elsif (!$nreq) {	453	} elsif (!$nreq) {
427	# finished	454	# finished
428	undef $statcb;	455	undef $statcb;
429	undef $schedcb;	456	undef $schedcb;
…		…
438	$nreq--;	465	$nreq--;
439	push @nondirs, $entry;	466	push @nondirs, $entry;
440	&$schedcb;	467	&$schedcb;
441	} else {	468	} else {
442	# need to check for real directory	469	# need to check for real directory
443	aio_lstat "$path/$entry", sub {	470	add $grp aio_lstat "$path/$entry", sub {
444	$nreq--;	471	$nreq--;
445		472
446	if (-d _) {	473	if (-d _) {
447	push @dirs, $entry;	474	push @dirs, $entry;
448		475
…		…
461		488
462	&$schedcb while @$entries && $nreq < $maxreq;	489	&$schedcb while @$entries && $nreq < $maxreq;
463	};	490	};
464	};	491	};
465	};	492	};
		493
		494	$grp
466	}	495	}
467		496
468	=item aio_fsync $fh, $callback->($status)	497	=item aio_fsync $fh, $callback->($status)
469		498
470	Asynchronously call fsync on the given filehandle and call the callback	499	Asynchronously call fsync on the given filehandle and call the callback
…		…
475	Asynchronously call fdatasync on the given filehandle and call the	504	Asynchronously call fdatasync on the given filehandle and call the
476	callback with the fdatasync result code.	505	callback with the fdatasync result code.
477		506
478	If this call isn't available because your OS lacks it or it couldn't be	507	If this call isn't available because your OS lacks it or it couldn't be
479	detected, it will be emulated by calling C<fsync> instead.	508	detected, it will be emulated by calling C<fsync> instead.
		509
		510	=item aio_group $callback->()
		511
		512	[EXPERIMENTAL]
		513
		514	This is a very special aio request: Instead of doing something, it is a
		515	container for other aio requests, which is useful if you want to bundle
		516	many requests into a single, composite, request.
		517
		518	Returns an object of class L<IO::AIO::GRP>. See its documentation below
		519	for more info.
		520
		521	Example:
		522
		523	my $grp = aio_group sub {
		524	print "all stats done\n";
		525	};
		526
		527	add $grp
		528	(aio_stat ...),
		529	(aio_stat ...),
		530	...;
		531
		532	=item IO::AIO::aio_sleep $fractional_seconds, $callback->() NOT EXPORTED
		533
		534	Mainly used for debugging and benchmarking, this aio request puts one of
		535	the request workers to sleep for the given time.
		536
		537	While it is theoretically handy to have simple I/O scheduling requests
		538	like sleep and file handle readable/writable, the overhead this creates
		539	is immense, so do not use this function except to put your application
		540	under artificial I/O pressure.
		541
		542	=back
		543
		544	=head2 IO::AIO::REQ CLASS
		545
		546	All non-aggregate C<aio_*> functions return an object of this class when
		547	called in non-void context.
		548
		549	A request always moves through the following five states in its lifetime,
		550	in order: B<ready> (request has been created, but has not been executed
		551	yet), B<execute> (request is currently being executed), B<pending>
		552	(request has been executed but callback has not been called yet),
		553	B<result> (results are being processed synchronously, includes calling the
		554	callback) and B<done> (request has reached the end of its lifetime and
		555	holds no resources anymore).
		556
		557	=over 4
		558
		559	=item $req->cancel
		560
		561	Cancels the request, if possible. Has the effect of skipping execution
		562	when entering the B<execute> state and skipping calling the callback when
		563	entering the the B<result> state, but will leave the request otherwise
		564	untouched. That means that requests that currently execute will not be
		565	stopped and resources held by the request will not be freed prematurely.
		566
		567	=back
		568
		569	=head2 IO::AIO::GRP CLASS
		570
		571	This class is a subclass of L<IO::AIO::REQ>, so all its methods apply to
		572	objects of this class, too.
		573
		574	A IO::AIO::GRP object is a special request that can contain multiple other
		575	aio requests.
		576
		577	You create one by calling the C<aio_group> constructing function with a
		578	callback that will be called when all contained requests have entered the
		579	C<done> state:
		580
		581	my $grp = aio_group sub {
		582	print "all requests are done\n";
		583	};
		584
		585	You add requests by calling the C<add> method with one or more
		586	C<IO::AIO::REQ> objects:
		587
		588	$grp->add (aio_unlink "...");
		589
		590	add $grp aio_stat "...", sub { ... };
		591
		592	This makes it very easy to create composite requests (see the source of
		593	C<aio_move> for an application) that work and feel like simple requests.
		594
		595	The IO::AIO::GRP objects will be cleaned up during calls to
		596	C<IO::AIO::poll_cb>, just like any other request.
		597
		598	They can be canceled like any other request. Canceling will cancel not
		599	just the request itself, but also all requests it contains.
		600
		601	They can also can also be added to other IO::AIO::GRP objects.
		602
		603	Their lifetime, simplified, looks like this: when they are empty, they
		604	will finish very quickly. If they contain only requests that are in the
		605	C<done> state, they will also finish. Otherwise they will continue to
		606	exist.
		607
		608	That means after creating a group you have some time to add requests. And
		609	in the callbacks of those requests, you can add further requests to the
		610	group. And only when all those requests have finished will the the group
		611	itself finish.
		612
		613	=over 4
		614
		615	=item $grp->add (...)
		616
		617	=item add $grp ...
		618
		619	Add one or more requests to the group. Any type of L<IO::AIO::REQ> can
		620	be added, including other groups, as long as you do not create circular
		621	dependencies.
		622
		623	Returns all its arguments.
480		624
481	=back	625	=back
482		626
483	=head2 SUPPORT FUNCTIONS	627	=head2 SUPPORT FUNCTIONS
484		628
…		…
612	}	756	}
613		757
614	1;	758	1;
615		759
616	=head2 FORK BEHAVIOUR	760	=head2 FORK BEHAVIOUR
		761
		762	This module should do "the right thing" when the process using it forks:
617		763
618	Before the fork, IO::AIO enters a quiescent state where no requests	764	Before the fork, IO::AIO enters a quiescent state where no requests
619	can be added in other threads and no results will be processed. After	765	can be added in other threads and no results will be processed. After
620	the fork the parent simply leaves the quiescent state and continues	766	the fork the parent simply leaves the quiescent state and continues
621	request/result processing, while the child clears the request/result	767	request/result processing, while the child clears the request/result
622	queue (so the requests started before the fork will only be handled in	768	queue (so the requests started before the fork will only be handled in
623	the parent). Threats will be started on demand until the limit ste in the	769	the parent). Threads will be started on demand until the limit ste in the
624	parent process has been reached again.	770	parent process has been reached again.
625		771
		772	In short: the parent will, after a short pause, continue as if fork had
		773	not been called, while the child will act as if IO::AIO has not been used
		774	yet.
		775
626	=head1 SEE ALSO	776	=head1 SEE ALSO
627		777
628	L<Coro>, L<Linux::AIO>.	778	L<Coro>, L<Linux::AIO> (obsolete).
629		779
630	=head1 AUTHOR	780	=head1 AUTHOR
631		781
632	Marc Lehmann <schmorp@schmorp.de>	782	Marc Lehmann <schmorp@schmorp.de>
633	http://home.schmorp.de/	783	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.50 by root, Sat Jun 24 16:27:02 2006 UTC vs. Revision 1.57 by root, Sun Oct 22 01:28:31 2006 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.50 by root, Sat Jun 24 16:27:02 2006 UTC vs.
Revision 1.57 by root, Sun Oct 22 01:28:31 2006 UTC