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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs.
Revision 1.226 by root, Mon May 28 17:00:19 2012 UTC

…		…
168	use common::sense;	168	use common::sense;
169		169
170	use base 'Exporter';	170	use base 'Exporter';
171		171
172	BEGIN {	172	BEGIN {
173	our $VERSION = '3.93';	173	our $VERSION = '4.15';
174		174
175	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close	175	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx	176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync aio_fsync	177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
178	aio_fdatasync aio_sync_file_range aio_fallocate	178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate
179	aio_pathsync aio_readahead	179	aio_pathsync aio_readahead aio_fiemap
180	aio_rename aio_link aio_move aio_copy aio_group	180	aio_rename aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	182	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	183	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs);	184	aio_statvfs
		185	aio_wd);
185		186
186	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	187	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
187	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	188	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
188	min_parallel max_parallel max_idle idle_timeout	189	min_parallel max_parallel max_idle idle_timeout
189	nreqs nready npending nthreads	190	nreqs nready npending nthreads
…		…
205		206
206	This section simply lists the prototypes of the most important functions	207	This section simply lists the prototypes of the most important functions
207	for quick reference. See the following sections for function-by-function	208	for quick reference. See the following sections for function-by-function
208	documentation.	209	documentation.
209		210
		211	aio_wd $pathname, $callback->($wd)
210	aio_open $pathname, $flags, $mode, $callback->($fh)	212	aio_open $pathname, $flags, $mode, $callback->($fh)
211	aio_close $fh, $callback->($status)	213	aio_close $fh, $callback->($status)
		214	aio_seek $fh,$offset,$whence, $callback->($offs)
212	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	215	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
213	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	216	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
214	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	217	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
215	aio_readahead $fh,$offset,$length, $callback->($retval)	218	aio_readahead $fh,$offset,$length, $callback->($retval)
216	aio_stat $fh_or_path, $callback->($status)	219	aio_stat $fh_or_path, $callback->($status)
217	aio_lstat $fh, $callback->($status)	220	aio_lstat $fh, $callback->($status)
218	aio_statvfs $fh_or_path, $callback->($statvfs)	221	aio_statvfs $fh_or_path, $callback->($statvfs)
219	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	222	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
220	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	223	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		224	aio_chmod $fh_or_path, $mode, $callback->($status)
221	aio_truncate $fh_or_path, $offset, $callback->($status)	225	aio_truncate $fh_or_path, $offset, $callback->($status)
222	aio_chmod $fh_or_path, $mode, $callback->($status)
223	aio_unlink $pathname, $callback->($status)	226	aio_unlink $pathname, $callback->($status)
224	aio_mknod $path, $mode, $dev, $callback->($status)	227	aio_mknod $pathname, $mode, $dev, $callback->($status)
225	aio_link $srcpath, $dstpath, $callback->($status)	228	aio_link $srcpath, $dstpath, $callback->($status)
226	aio_symlink $srcpath, $dstpath, $callback->($status)	229	aio_symlink $srcpath, $dstpath, $callback->($status)
227	aio_readlink $path, $callback->($link)	230	aio_readlink $pathname, $callback->($link)
228	aio_realpath $path, $callback->($link)	231	aio_realpath $pathname, $callback->($link)
229	aio_rename $srcpath, $dstpath, $callback->($status)	232	aio_rename $srcpath, $dstpath, $callback->($status)
230	aio_mkdir $pathname, $mode, $callback->($status)	233	aio_mkdir $pathname, $mode, $callback->($status)
231	aio_rmdir $pathname, $callback->($status)	234	aio_rmdir $pathname, $callback->($status)
232	aio_readdir $pathname, $callback->($entries)	235	aio_readdir $pathname, $callback->($entries)
233	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	236	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
234	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	237	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
235	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN	238	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		239	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
236	aio_load $path, $data, $callback->($status)	240	aio_load $pathname, $data, $callback->($status)
237	aio_copy $srcpath, $dstpath, $callback->($status)	241	aio_copy $srcpath, $dstpath, $callback->($status)
238	aio_move $srcpath, $dstpath, $callback->($status)	242	aio_move $srcpath, $dstpath, $callback->($status)
239	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
240	aio_rmtree $path, $callback->($status)	243	aio_rmtree $pathname, $callback->($status)
241	aio_sync $callback->($status)	244	aio_sync $callback->($status)
		245	aio_syncfs $fh, $callback->($status)
242	aio_fsync $fh, $callback->($status)	246	aio_fsync $fh, $callback->($status)
243	aio_fdatasync $fh, $callback->($status)	247	aio_fdatasync $fh, $callback->($status)
244	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	248	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
245	aio_pathsync $path, $callback->($status)	249	aio_pathsync $pathname, $callback->($status)
246	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	250	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
247	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	251	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
248	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	252	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
249	aio_mlockall $flags, $callback->($status)	253	aio_mlockall $flags, $callback->($status)
250	aio_group $callback->(...)	254	aio_group $callback->(...)
…		…
268	IO::AIO::nready	272	IO::AIO::nready
269	IO::AIO::npending	273	IO::AIO::npending
270		274
271	IO::AIO::sendfile $ofh, $ifh, $offset, $count	275	IO::AIO::sendfile $ofh, $ifh, $offset, $count
272	IO::AIO::fadvise $fh, $offset, $len, $advice	276	IO::AIO::fadvise $fh, $offset, $len, $advice
		277	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
		278	IO::AIO::munmap $scalar
273	IO::AIO::madvise $scalar, $offset, $length, $advice	279	IO::AIO::madvise $scalar, $offset, $length, $advice
274	IO::AIO::mprotect $scalar, $offset, $length, $protect	280	IO::AIO::mprotect $scalar, $offset, $length, $protect
275	IO::AIO::munlock $scalar, $offset = 0, $length = undef	281	IO::AIO::munlock $scalar, $offset = 0, $length = undef
276	IO::AIO::munlockall	282	IO::AIO::munlockall
277		283
278	=head2 AIO REQUEST FUNCTIONS	284	=head2 API NOTES
279		285
280	All the C<aio_*> calls are more or less thin wrappers around the syscall	286	All the C<aio_*> calls are more or less thin wrappers around the syscall
281	with the same name (sans C<aio_>). The arguments are similar or identical,	287	with the same name (sans C<aio_>). The arguments are similar or identical,
282	and they all accept an additional (and optional) C<$callback> argument	288	and they all accept an additional (and optional) C<$callback> argument
283	which must be a code reference. This code reference will get called with	289	which must be a code reference. This code reference will be called after
284	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	290	the syscall has been executed in an asynchronous fashion. The results
285	perl, which usually delivers "false") as its sole argument after the given	291	of the request will be passed as arguments to the callback (and, if an
286	syscall has been executed asynchronously.	292	error occured, in C<$!>) - for most requests the syscall return code (e.g.
		293	most syscalls return C<-1> on error, unlike perl, which usually delivers
		294	"false").
		295
		296	Some requests (such as C<aio_readdir>) pass the actual results and
		297	communicate failures by passing C<undef>.
287		298
288	All functions expecting a filehandle keep a copy of the filehandle	299	All functions expecting a filehandle keep a copy of the filehandle
289	internally until the request has finished.	300	internally until the request has finished.
290		301
291	All functions return request objects of type L<IO::AIO::REQ> that allow	302	All functions return request objects of type L<IO::AIO::REQ> that allow
292	further manipulation of those requests while they are in-flight.	303	further manipulation of those requests while they are in-flight.
293		304
294	The pathnames you pass to these routines I<must> be absolute and	305	The pathnames you pass to these routines I<should> be absolute. The
295	encoded as octets. The reason for the former is that at the time the	306	reason for this is that at the time the request is being executed, the
296	request is being executed, the current working directory could have	307	current working directory could have changed. Alternatively, you can
297	changed. Alternatively, you can make sure that you never change the	308	make sure that you never change the current working directory anywhere
298	current working directory anywhere in the program and then use relative	309	in the program and then use relative paths. You can also take advantage
299	paths.	310	of IO::AIOs working directory abstraction, that lets you specify paths
		311	relative to some previously-opened "working directory object" - see the
		312	description of the C<IO::AIO::WD> class later in this document.
300		313
301	To encode pathnames as octets, either make sure you either: a) always pass	314	To encode pathnames as octets, either make sure you either: a) always pass
302	in filenames you got from outside (command line, readdir etc.) without	315	in filenames you got from outside (command line, readdir etc.) without
303	tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode	316	tinkering, b) are in your native filesystem encoding, c) use the Encode
304	your pathnames to the locale (or other) encoding in effect in the user	317	module and encode your pathnames to the locale (or other) encoding in
305	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	318	effect in the user environment, d) use Glib::filename_from_unicode on
306	use something else to ensure your scalar has the correct contents.	319	unicode filenames or e) use something else to ensure your scalar has the
		320	correct contents.
307		321
308	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	322	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
309	handles correctly whether it is set or not.	323	handles correctly whether it is set or not.
		324
		325	=head2 AIO REQUEST FUNCTIONS
310		326
311	=over 4	327	=over 4
312		328
313	=item $prev_pri = aioreq_pri [$pri]	329	=item $prev_pri = aioreq_pri [$pri]
314		330
…		…
396		412
397	Or in other words: the file descriptor will be closed, but it will not be	413	Or in other words: the file descriptor will be closed, but it will not be
398	free for reuse until the perl filehandle is closed.	414	free for reuse until the perl filehandle is closed.
399		415
400	=cut	416	=cut
		417
		418	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		419
		420	Seeks the filehandle to the new C<$offset>, similarly to perl's
		421	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		422	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		423	C<IO::AIO::SEEK_END>).
		424
		425	The resulting absolute offset will be passed to the callback, or C<-1> in
		426	case of an error.
		427
		428	In theory, the C<$whence> constants could be different than the
		429	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		430	so don't panic.
		431
		432	As a GNU/Linux (and maybe Solaris) extension, also the constants
		433	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		434	could be found. No guarantees about suitability for use in C<aio_seek> or
		435	Perl's C<sysseek> can be made though, although I would naively assume they
		436	"just work".
401		437
402	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	438	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
403		439
404	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	440	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
405		441
…		…
613		649
614	Asynchronously unlink (delete) a file and call the callback with the	650	Asynchronously unlink (delete) a file and call the callback with the
615	result code.	651	result code.
616		652
617		653
618	=item aio_mknod $path, $mode, $dev, $callback->($status)	654	=item aio_mknod $pathname, $mode, $dev, $callback->($status)
619		655
620	[EXPERIMENTAL]	656	[EXPERIMENTAL]
621		657
622	Asynchronously create a device node (or fifo). See mknod(2).	658	Asynchronously create a device node (or fifo). See mknod(2).
623		659
624	The only (POSIX-) portable way of calling this function is:	660	The only (POSIX-) portable way of calling this function is:
625		661
626	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	662	aio_mknod $pathname, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
627		663
628	See C<aio_stat> for info about some potentially helpful extra constants	664	See C<aio_stat> for info about some potentially helpful extra constants
629	and functions.	665	and functions.
630		666
631	=item aio_link $srcpath, $dstpath, $callback->($status)	667	=item aio_link $srcpath, $dstpath, $callback->($status)
…		…
638		674
639	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	675	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
640	the path C<$dstpath> and call the callback with the result code.	676	the path C<$dstpath> and call the callback with the result code.
641		677
642		678
643	=item aio_readlink $path, $callback->($link)	679	=item aio_readlink $pathname, $callback->($link)
644		680
645	Asynchronously read the symlink specified by C<$path> and pass it to	681	Asynchronously read the symlink specified by C<$path> and pass it to
646	the callback. If an error occurs, nothing or undef gets passed to the	682	the callback. If an error occurs, nothing or undef gets passed to the
647	callback.	683	callback.
648		684
649		685
650	=item aio_realpath $path, $callback->($path)	686	=item aio_realpath $pathname, $callback->($path)
651		687
652	Asynchronously make the path absolute and resolve any symlinks in	688	Asynchronously make the path absolute and resolve any symlinks in
653	C<$path>. The resulting path only consists of directories (Same as	689	C<$path>. The resulting path only consists of directories (Same as
654	L<Cwd::realpath>).	690	L<Cwd::realpath>).
655		691
…		…
686	array-ref with the filenames.	722	array-ref with the filenames.
687		723
688		724
689	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)	725	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
690		726
691	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune	727	Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to
692	behaviour and output format. In case of an error, C<$entries> will be	728	tune behaviour and output format. In case of an error, C<$entries> will be
693	C<undef>.	729	C<undef>.
694		730
695	The flags are a combination of the following constants, ORed together (the	731	The flags are a combination of the following constants, ORed together (the
696	flags will also be passed to the callback, possibly modified):	732	flags will also be passed to the callback, possibly modified):
697		733
…		…
744		780
745	=item IO::AIO::READDIR_FOUND_UNKNOWN	781	=item IO::AIO::READDIR_FOUND_UNKNOWN
746		782
747	This flag should not be set when calling C<aio_readdirx>. Instead, it	783	This flag should not be set when calling C<aio_readdirx>. Instead, it
748	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	784	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
749	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all	785	C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all
750	C<$type>'s are known, which can be used to speed up some algorithms.	786	C<$type>'s are known, which can be used to speed up some algorithms.
751		787
752	=back	788	=back
753		789
754		790
755	=item aio_load $path, $data, $callback->($status)	791	=item aio_load $pathname, $data, $callback->($status)
756		792
757	This is a composite request that tries to fully load the given file into	793	This is a composite request that tries to fully load the given file into
758	memory. Status is the same as with aio_read.	794	memory. Status is the same as with aio_read.
759		795
760	=cut	796	=cut
…		…
895	};	931	};
896		932
897	$grp	933	$grp
898	}	934	}
899		935
900	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	936	=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
901		937
902	Scans a directory (similar to C<aio_readdir>) but additionally tries to	938	Scans a directory (similar to C<aio_readdir>) but additionally tries to
903	efficiently separate the entries of directory C<$path> into two sets of	939	efficiently separate the entries of directory C<$path> into two sets of
904	names, directories you can recurse into (directories), and ones you cannot	940	names, directories you can recurse into (directories), and ones you cannot
905	recurse into (everything else, including symlinks to directories).	941	recurse into (everything else, including symlinks to directories).
…		…
936	Then entries will be sorted into likely directories a non-initial dot	972	Then entries will be sorted into likely directories a non-initial dot
937	currently) and likely non-directories (see C<aio_readdirx>). Then every	973	currently) and likely non-directories (see C<aio_readdirx>). Then every
938	entry plus an appended C</.> will be C<stat>'ed, likely directories first,	974	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
939	in order of their inode numbers. If that succeeds, it assumes that the	975	in order of their inode numbers. If that succeeds, it assumes that the
940	entry is a directory or a symlink to directory (which will be checked	976	entry is a directory or a symlink to directory (which will be checked
941	seperately). This is often faster than stat'ing the entry itself because	977	separately). This is often faster than stat'ing the entry itself because
942	filesystems might detect the type of the entry without reading the inode	978	filesystems might detect the type of the entry without reading the inode
943	data (e.g. ext2fs filetype feature), even on systems that cannot return	979	data (e.g. ext2fs filetype feature), even on systems that cannot return
944	the filetype information on readdir.	980	the filetype information on readdir.
945		981
946	If the known number of directories (link count - 2) has been reached, the	982	If the known number of directories (link count - 2) has been reached, the
…		…
962		998
963	my $grp = aio_group $cb;	999	my $grp = aio_group $cb;
964		1000
965	$maxreq = 4 if $maxreq <= 0;	1001	$maxreq = 4 if $maxreq <= 0;
966		1002
967	# stat once	1003	# get a wd object
968	aioreq_pri $pri;	1004	aioreq_pri $pri;
969	add $grp aio_stat $path, sub {	1005	add $grp aio_wd $path, sub {
		1006	$_[0]
970	return $grp->result () if $_[0];	1007	or return $grp->result ();
971	my $now = time;
972	my $hash1 = join ":", (stat _)[0,1,3,7,9];
973		1008
974	# read the directory entries	1009	my $wd = [shift, "."];
		1010
		1011	# stat once
975	aioreq_pri $pri;	1012	aioreq_pri $pri;
976	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {	1013	add $grp aio_stat $wd, sub {
977	my $entries = shift
978	or return $grp->result ();	1014	return $grp->result () if $_[0];
		1015	my $now = time;
		1016	my $hash1 = join ":", (stat _)[0,1,3,7,9];
979		1017
980	# stat the dir another time	1018	# read the directory entries
981	aioreq_pri $pri;	1019	aioreq_pri $pri;
		1020	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {
		1021	my $entries = shift
		1022	or return $grp->result ();
		1023
		1024	# stat the dir another time
		1025	aioreq_pri $pri;
982	add $grp aio_stat $path, sub {	1026	add $grp aio_stat $wd, sub {
983	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1027	my $hash2 = join ":", (stat _)[0,1,3,7,9];
984		1028
985	my $ndirs;	1029	my $ndirs;
986		1030
987	# take the slow route if anything looks fishy	1031	# take the slow route if anything looks fishy
988	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	1032	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
989	$ndirs = -1;	1033	$ndirs = -1;
990	} else {	1034	} else {
991	# if nlink == 2, we are finished	1035	# if nlink == 2, we are finished
992	# for non-posix-fs's, we rely on nlink < 2	1036	# for non-posix-fs's, we rely on nlink < 2
993	$ndirs = (stat _)[3] - 2	1037	$ndirs = (stat _)[3] - 2
994	or return $grp->result ([], $entries);	1038	or return $grp->result ([], $entries);
995	}	1039	}
996		1040
997	my (@dirs, @nondirs);	1041	my (@dirs, @nondirs);
998		1042
999	my $statgrp = add $grp aio_group sub {	1043	my $statgrp = add $grp aio_group sub {
1000	$grp->result (\@dirs, \@nondirs);	1044	$grp->result (\@dirs, \@nondirs);
1001	};	1045	};
1002		1046
1003	limit $statgrp $maxreq;	1047	limit $statgrp $maxreq;
1004	feed $statgrp sub {	1048	feed $statgrp sub {
1005	return unless @$entries;	1049	return unless @$entries;
1006	my $entry = shift @$entries;	1050	my $entry = shift @$entries;
1007		1051
1008	aioreq_pri $pri;	1052	aioreq_pri $pri;
		1053	$wd->[1] = "$entry/.";
1009	add $statgrp aio_stat "$path/$entry/.", sub {	1054	add $statgrp aio_stat $wd, sub {
1010	if ($_[0] < 0) {	1055	if ($_[0] < 0) {
1011	push @nondirs, $entry;	1056	push @nondirs, $entry;
1012	} else {	1057	} else {
1013	# need to check for real directory	1058	# need to check for real directory
1014	aioreq_pri $pri;	1059	aioreq_pri $pri;
		1060	$wd->[1] = $entry;
1015	add $statgrp aio_lstat "$path/$entry", sub {	1061	add $statgrp aio_lstat $wd, sub {
1016	if (-d _) {	1062	if (-d _) {
1017	push @dirs, $entry;	1063	push @dirs, $entry;
1018		1064
1019	unless (--$ndirs) {	1065	unless (--$ndirs) {
1020	push @nondirs, @$entries;	1066	push @nondirs, @$entries;
1021	feed $statgrp;	1067	feed $statgrp;
		1068	}
		1069	} else {
		1070	push @nondirs, $entry;
1022	}	1071	}
1023	} else {
1024	push @nondirs, $entry;
1025	}	1072	}
1026	}	1073	}
1027	}	1074	};
1028	};	1075	};
1029	};	1076	};
1030	};	1077	};
1031	};	1078	};
1032	};	1079	};
1033		1080
1034	$grp	1081	$grp
1035	}	1082	}
1036		1083
1037	=item aio_rmtree $path, $callback->($status)	1084	=item aio_rmtree $pathname, $callback->($status)
1038		1085
1039	Delete a directory tree starting (and including) C<$path>, return the	1086	Delete a directory tree starting (and including) C<$path>, return the
1040	status of the final C<rmdir> only. This is a composite request that	1087	status of the final C<rmdir> only. This is a composite request that
1041	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1088	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1042	everything else.	1089	everything else.
…		…
1084	callback with the fdatasync result code.	1131	callback with the fdatasync result code.
1085		1132
1086	If this call isn't available because your OS lacks it or it couldn't be	1133	If this call isn't available because your OS lacks it or it couldn't be
1087	detected, it will be emulated by calling C<fsync> instead.	1134	detected, it will be emulated by calling C<fsync> instead.
1088		1135
		1136	=item aio_syncfs $fh, $callback->($status)
		1137
		1138	Asynchronously call the syncfs syscall to sync the filesystem associated
		1139	to the given filehandle and call the callback with the syncfs result
		1140	code. If syncfs is not available, calls sync(), but returns C<-1> and sets
		1141	errno to C<ENOSYS> nevertheless.
		1142
1089	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	1143	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
1090		1144
1091	Sync the data portion of the file specified by C<$offset> and C<$length>	1145	Sync the data portion of the file specified by C<$offset> and C<$length>
1092	to disk (but NOT the metadata), by calling the Linux-specific	1146	to disk (but NOT the metadata), by calling the Linux-specific
1093	sync_file_range call. If sync_file_range is not available or it returns	1147	sync_file_range call. If sync_file_range is not available or it returns
…		…
1096	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,	1150	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
1097	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and	1151	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1098	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range	1152	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
1099	manpage for details.	1153	manpage for details.
1100		1154
1101	=item aio_pathsync $path, $callback->($status)	1155	=item aio_pathsync $pathname, $callback->($status)
1102		1156
1103	This request tries to open, fsync and close the given path. This is a	1157	This request tries to open, fsync and close the given path. This is a
1104	composite request intended to sync directories after directory operations	1158	composite request intended to sync directories after directory operations
1105	(E.g. rename). This might not work on all operating systems or have any	1159	(E.g. rename). This might not work on all operating systems or have any
1106	specific effect, but usually it makes sure that directory changes get	1160	specific effect, but usually it makes sure that directory changes get
…		…
1203		1257
1204	Example: asynchronously lock all current and future pages into memory.	1258	Example: asynchronously lock all current and future pages into memory.
1205		1259
1206	aio_mlockall IO::AIO::MCL_FUTURE;	1260	aio_mlockall IO::AIO::MCL_FUTURE;
1207		1261
		1262	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1263
		1264	Queries the extents of the given file (by calling the Linux FIEMAP ioctl,
		1265	see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the
		1266	C<ioctl> is not available on your OS, then this rquiest will fail with
		1267	C<ENOSYS>.
		1268
		1269	C<$start> is the starting offset to query extents for, C<$length> is the
		1270	size of the range to query - if it is C<undef>, then the whole file will
		1271	be queried.
		1272
		1273	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1274	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1275	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1276	the data portion.
		1277
		1278	C<$count> is the maximum number of extent records to return. If it is
		1279	C<undef>, then IO::AIO queries all extents of the file. As a very special
		1280	case, if it is C<0>, then the callback receives the number of extents
		1281	instead of the extents themselves.
		1282
		1283	If an error occurs, the callback receives no arguments. The special
		1284	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1285
		1286	Otherwise, the callback receives an array reference with extent
		1287	structures. Each extent structure is an array reference itself, with the
		1288	following members:
		1289
		1290	[$logical, $physical, $length, $flags]
		1291
		1292	Flags is any combination of the following flag values (typically either C<0>
		1293	or C<IO::AIO::FIEMAP_EXTENT_LAST>):
		1294
		1295	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1296	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1297	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1298	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1299	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1300	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1301
1208	=item aio_group $callback->(...)	1302	=item aio_group $callback->(...)
1209		1303
1210	This is a very special aio request: Instead of doing something, it is a	1304	This is a very special aio request: Instead of doing something, it is a
1211	container for other aio requests, which is useful if you want to bundle	1305	container for other aio requests, which is useful if you want to bundle
1212	many requests into a single, composite, request with a definite callback	1306	many requests into a single, composite, request with a definite callback
…		…
1248	like sleep and file handle readable/writable, the overhead this creates is	1342	like sleep and file handle readable/writable, the overhead this creates is
1249	immense (it blocks a thread for a long time) so do not use this function	1343	immense (it blocks a thread for a long time) so do not use this function
1250	except to put your application under artificial I/O pressure.	1344	except to put your application under artificial I/O pressure.
1251		1345
1252	=back	1346	=back
		1347
		1348
		1349	=head2 IO::AIO::WD - multiple working directories
		1350
		1351	Your process only has one current working directory, which is used by all
		1352	threads. This makes it hard to use relative paths (some other component
		1353	could call C<chdir> at any time, and it is hard to control when the path
		1354	will be used by IO::AIO).
		1355
		1356	One solution for this is to always use absolute paths. This usually works,
		1357	but can be quite slow (the kernel has to walk the whole path on every
		1358	access), and can also be a hassle to implement.
		1359
		1360	Newer POSIX systems have a number of functions (openat, fdopendir,
		1361	futimensat and so on) that make it possible to specify working directories
		1362	per operation.
		1363
		1364	For portability, and because the clowns who "designed", or shall I write,
		1365	perpetrated this new interface were obviously half-drunk, this abstraction
		1366	cannot be perfect, though.
		1367
		1368	IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD
		1369	object. This object stores the canonicalised, absolute version of the
		1370	path, and on systems that allow it, also a directory file descriptor.
		1371
		1372	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
		1373	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
		1374	object and a pathname instead (or the IO::AIO::WD object alone, which
		1375	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
		1376	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
		1377	to that IO::AIO::WD object.
		1378
		1379	For example, to get a wd object for F</etc> and then stat F<passwd>
		1380	inside, you would write:
		1381
		1382	aio_wd "/etc", sub {
		1383	my $etcdir = shift;
		1384
		1385	# although $etcdir can be undef on error, there is generally no reason
		1386	# to check for errors here, as aio_stat will fail with ENOENT
		1387	# when $etcdir is undef.
		1388
		1389	aio_stat [$etcdir, "passwd"], sub {
		1390	# yay
		1391	};
		1392	};
		1393
		1394	That C<aio_wd> is a request and not a normal function shows that creating
		1395	an IO::AIO::WD object is itself a potentially blocking operation, which is
		1396	why it is done asynchronously.
		1397
		1398	To stat the directory obtained with C<aio_wd> above, one could write
		1399	either of the following three request calls:
		1400
		1401	aio_lstat "/etc" , sub { ... # pathname as normal string
		1402	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1403	aio_lstat $wd , sub { ... # shorthand for the previous
		1404
		1405	As with normal pathnames, IO::AIO keeps a copy of the working directory
		1406	object and the pathname string, so you could write the following without
		1407	causing any issues due to C<$path> getting reused:
		1408
		1409	my $path = [$wd, undef];
		1410
		1411	for my $name (qw(abc def ghi)) {
		1412	$path->[1] = $name;
		1413	aio_stat $path, sub {
		1414	# ...
		1415	};
		1416	}
		1417
		1418	There are some caveats: when directories get renamed (or deleted), the
		1419	pathname string doesn't change, so will point to the new directory (or
		1420	nowhere at all), while the directory fd, if available on the system,
		1421	will still point to the original directory. Most functions accepting a
		1422	pathname will use the directory fd on newer systems, and the string on
		1423	older systems. Some functions (such as realpath) will always rely on the
		1424	string form of the pathname.
		1425
		1426	So this fucntionality is mainly useful to get some protection against
		1427	C<chdir>, to easily get an absolute path out of a relative path for future
		1428	reference, and to speed up doing many operations in the same directory
		1429	(e.g. when stat'ing all files in a directory).
		1430
		1431	The following functions implement this working directory abstraction:
		1432
		1433	=over 4
		1434
		1435	=item aio_wd $pathname, $callback->($wd)
		1436
		1437	Asynchonously canonicalise the given pathname and convert it to an
		1438	IO::AIO::WD object representing it. If possible and supported on the
		1439	system, also open a directory fd to speed up pathname resolution relative
		1440	to this working directory.
		1441
		1442	If something goes wrong, then C<undef> is passwd to the callback instead
		1443	of a working directory object and C<$!> is set appropriately. Since
		1444	passing C<undef> as working directory component of a pathname fails the
		1445	request with C<ENOENT>, there is often no need for error checking in the
		1446	C<aio_wd> callback, as future requests using the value will fail in the
		1447	expected way.
		1448
		1449	If this call isn't available because your OS lacks it or it couldn't be
		1450	detected, it will be emulated by calling C<fsync> instead.
		1451
		1452	=item IO::AIO::CWD
		1453
		1454	This is a compiletime constant (object) that represents the process
		1455	current working directory.
		1456
		1457	Specifying this object as working directory object for a pathname is as
		1458	if the pathname would be specified directly, without a directory object,
		1459	e.g., these calls are functionally identical:
		1460
		1461	aio_stat "somefile", sub { ... };
		1462	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
		1463
		1464	=back
		1465
1253		1466
1254	=head2 IO::AIO::REQ CLASS	1467	=head2 IO::AIO::REQ CLASS
1255		1468
1256	All non-aggregate C<aio_*> functions return an object of this class when	1469	All non-aggregate C<aio_*> functions return an object of this class when
1257	called in non-void context.	1470	called in non-void context.
…		…
1375		1588
1376	Sets a feeder/generator on this group: every group can have an attached	1589	Sets a feeder/generator on this group: every group can have an attached
1377	generator that generates requests if idle. The idea behind this is that,	1590	generator that generates requests if idle. The idea behind this is that,
1378	although you could just queue as many requests as you want in a group,	1591	although you could just queue as many requests as you want in a group,
1379	this might starve other requests for a potentially long time. For example,	1592	this might starve other requests for a potentially long time. For example,
1380	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,	1593	C<aio_scandir> might generate hundreds of thousands of C<aio_stat>
1381	delaying any later requests for a long time.	1594	requests, delaying any later requests for a long time.
1382		1595
1383	To avoid this, and allow incremental generation of requests, you can	1596	To avoid this, and allow incremental generation of requests, you can
1384	instead a group and set a feeder on it that generates those requests. The	1597	instead a group and set a feeder on it that generates those requests. The
1385	feed callback will be called whenever there are few enough (see C<limit>,	1598	feed callback will be called whenever there are few enough (see C<limit>,
1386	below) requests active in the group itself and is expected to queue more	1599	below) requests active in the group itself and is expected to queue more
…		…
1665		1878
1666	=item IO::AIO::fadvise $fh, $offset, $len, $advice	1879	=item IO::AIO::fadvise $fh, $offset, $len, $advice
1667		1880
1668	Simply calls the C<posix_fadvise> function (see its	1881	Simply calls the C<posix_fadvise> function (see its
1669	manpage for details). The following advice constants are	1882	manpage for details). The following advice constants are
1670	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,	1883	available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1671	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,	1884	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1672	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.	1885	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1673		1886
1674	On systems that do not implement C<posix_fadvise>, this function returns	1887	On systems that do not implement C<posix_fadvise>, this function returns
1675	ENOSYS, otherwise the return value of C<posix_fadvise>.	1888	ENOSYS, otherwise the return value of C<posix_fadvise>.
1676		1889
1677	=item IO::AIO::madvise $scalar, $offset, $len, $advice	1890	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1678		1891
1679	Simply calls the C<posix_madvise> function (see its	1892	Simply calls the C<posix_madvise> function (see its
1680	manpage for details). The following advice constants are	1893	manpage for details). The following advice constants are
1681	avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	1894	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1682	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	1895	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
1683		1896
1684	On systems that do not implement C<posix_madvise>, this function returns	1897	On systems that do not implement C<posix_madvise>, this function returns
1685	ENOSYS, otherwise the return value of C<posix_madvise>.	1898	ENOSYS, otherwise the return value of C<posix_madvise>.
1686		1899
1687	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	1900	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1688		1901
1689	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	1902	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1690	$scalar (see its manpage for details). The following protect	1903	$scalar (see its manpage for details). The following protect
1691	constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	1904	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1692	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	1905	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1693		1906
1694	On systems that do not implement C<mprotect>, this function returns	1907	On systems that do not implement C<mprotect>, this function returns
1695	ENOSYS, otherwise the return value of C<mprotect>.	1908	ENOSYS, otherwise the return value of C<mprotect>.
1696		1909
…		…
1758	Calls the C<munlockall> function.	1971	Calls the C<munlockall> function.
1759		1972
1760	On systems that do not implement C<munlockall>, this function returns	1973	On systems that do not implement C<munlockall>, this function returns
1761	ENOSYS, otherwise the return value of C<munlockall>.	1974	ENOSYS, otherwise the return value of C<munlockall>.
1762		1975
		1976	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		1977
		1978	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		1979	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		1980	should be the file offset.
		1981
		1982	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		1983	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		1984	C<IO::AIO::SPLICE_F_GIFT>.
		1985
		1986	See the C<splice(2)> manpage for details.
		1987
		1988	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		1989
		1990	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
		1991	description for C<IO::AIO::splice> above for details.
		1992
1763	=back	1993	=back
1764		1994
1765	=cut	1995	=cut
1766		1996
1767	min_parallel 8;	1997	min_parallel 8;
…		…
1804	=head2 FORK BEHAVIOUR	2034	=head2 FORK BEHAVIOUR
1805		2035
1806	Usage of pthreads in a program changes the semantics of fork	2036	Usage of pthreads in a program changes the semantics of fork
1807	considerably. Specifically, only async-safe functions can be called after	2037	considerably. Specifically, only async-safe functions can be called after
1808	fork. Perl doesn't know about this, so in general, you cannot call fork	2038	fork. Perl doesn't know about this, so in general, you cannot call fork
1809	with defined behaviour in perl. IO::AIO uses pthreads, so this applies,	2039	with defined behaviour in perl if pthreads are involved. IO::AIO uses
1810	but many other extensions and (for inexplicable reasons) perl itself often	2040	pthreads, so this applies, but many other extensions and (for inexplicable
1811	is linked against pthreads, so this limitation applies.	2041	reasons) perl itself often is linked against pthreads, so this limitation
		2042	applies to quite a lot of perls.
1812		2043
1813	Some operating systems have extensions that allow safe use of fork, and	2044	This module no longer tries to fight your OS, or POSIX. That means IO::AIO
1814	this module should do "the right thing" on those, and tries on others. At	2045	only works in the process that loaded it. Forking is fully supported, but
1815	the time of this writing (2011) only GNU/Linux supports these extensions	2046	using IO::AIO in the child is not.
1816	to POSIX.	2047
		2048	You might get around by not I<using> IO::AIO before (or after)
		2049	forking. You could also try to call the L<IO::AIO::reinit> function in the
		2050	child:
		2051
		2052	=over 4
		2053
		2054	=item IO::AIO::reinit
		2055
		2056	Abandons all current requests and I/O threads and simply reinitialises all
		2057	data structures. This is not an operation supported by any standards, but
		2058	happens to work on GNU/Linux and some newer BSD systems.
		2059
		2060	The only reasonable use for this function is to call it after forking, if
		2061	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
		2062	the process will result in undefined behaviour. Calling it at any time
		2063	will also result in any undefined (by POSIX) behaviour.
		2064
		2065	=back
1817		2066
1818	=head2 MEMORY USAGE	2067	=head2 MEMORY USAGE
1819		2068
1820	Per-request usage:	2069	Per-request usage:
1821		2070

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs. Revision 1.226 by root, Mon May 28 17:00:19 2012 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs.
Revision 1.226 by root, Mon May 28 17:00:19 2012 UTC