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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.199 by root, Wed Jun 29 12:46:36 2011 UTC vs.
Revision 1.227 by root, Tue May 29 03:58:02 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 = '3.92';	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_sync aio_fsync	177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
178	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead	178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate
		179	aio_pathsync aio_readahead aio_fiemap
179	aio_rename aio_link aio_move aio_copy aio_group	180	aio_rename aio_link aio_move aio_copy aio_group
180	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
181	aio_chmod aio_utime aio_truncate	182	aio_chmod aio_utime aio_truncate
182	aio_msync aio_mtouch aio_mlock aio_mlockall	183	aio_msync aio_mtouch aio_mlock aio_mlockall
183	aio_statvfs);	184	aio_statvfs
		185	aio_wd);
184		186
185	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	187	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
186	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	188	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
187	min_parallel max_parallel max_idle idle_timeout	189	min_parallel max_parallel max_idle idle_timeout
188	nreqs nready npending nthreads	190	nreqs nready npending nthreads
…		…
204		206
205	This section simply lists the prototypes of the most important functions	207	This section simply lists the prototypes of the most important functions
206	for quick reference. See the following sections for function-by-function	208	for quick reference. See the following sections for function-by-function
207	documentation.	209	documentation.
208		210
		211	aio_wd $pathname, $callback->($wd)
209	aio_open $pathname, $flags, $mode, $callback->($fh)	212	aio_open $pathname, $flags, $mode, $callback->($fh)
210	aio_close $fh, $callback->($status)	213	aio_close $fh, $callback->($status)
		214	aio_seek $fh,$offset,$whence, $callback->($offs)
211	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	215	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
212	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	216	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
213	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	217	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
214	aio_readahead $fh,$offset,$length, $callback->($retval)	218	aio_readahead $fh,$offset,$length, $callback->($retval)
215	aio_stat $fh_or_path, $callback->($status)	219	aio_stat $fh_or_path, $callback->($status)
216	aio_lstat $fh, $callback->($status)	220	aio_lstat $fh, $callback->($status)
217	aio_statvfs $fh_or_path, $callback->($statvfs)	221	aio_statvfs $fh_or_path, $callback->($statvfs)
218	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	222	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
219	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)
220	aio_truncate $fh_or_path, $offset, $callback->($status)	225	aio_truncate $fh_or_path, $offset, $callback->($status)
221	aio_chmod $fh_or_path, $mode, $callback->($status)
222	aio_unlink $pathname, $callback->($status)	226	aio_unlink $pathname, $callback->($status)
223	aio_mknod $path, $mode, $dev, $callback->($status)	227	aio_mknod $pathname, $mode, $dev, $callback->($status)
224	aio_link $srcpath, $dstpath, $callback->($status)	228	aio_link $srcpath, $dstpath, $callback->($status)
225	aio_symlink $srcpath, $dstpath, $callback->($status)	229	aio_symlink $srcpath, $dstpath, $callback->($status)
226	aio_readlink $path, $callback->($link)	230	aio_readlink $pathname, $callback->($link)
		231	aio_realpath $pathname, $callback->($link)
227	aio_rename $srcpath, $dstpath, $callback->($status)	232	aio_rename $srcpath, $dstpath, $callback->($status)
228	aio_mkdir $pathname, $mode, $callback->($status)	233	aio_mkdir $pathname, $mode, $callback->($status)
229	aio_rmdir $pathname, $callback->($status)	234	aio_rmdir $pathname, $callback->($status)
230	aio_readdir $pathname, $callback->($entries)	235	aio_readdir $pathname, $callback->($entries)
231	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	236	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
232	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	237	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
233	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)
234	aio_load $path, $data, $callback->($status)	240	aio_load $pathname, $data, $callback->($status)
235	aio_copy $srcpath, $dstpath, $callback->($status)	241	aio_copy $srcpath, $dstpath, $callback->($status)
236	aio_move $srcpath, $dstpath, $callback->($status)	242	aio_move $srcpath, $dstpath, $callback->($status)
237	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
238	aio_rmtree $path, $callback->($status)	243	aio_rmtree $pathname, $callback->($status)
239	aio_sync $callback->($status)	244	aio_sync $callback->($status)
		245	aio_syncfs $fh, $callback->($status)
240	aio_fsync $fh, $callback->($status)	246	aio_fsync $fh, $callback->($status)
241	aio_fdatasync $fh, $callback->($status)	247	aio_fdatasync $fh, $callback->($status)
242	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	248	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
243	aio_pathsync $path, $callback->($status)	249	aio_pathsync $pathname, $callback->($status)
244	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	250	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
245	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	251	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
246	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	252	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
247	aio_mlockall $flags, $callback->($status)	253	aio_mlockall $flags, $callback->($status)
248	aio_group $callback->(...)	254	aio_group $callback->(...)
…		…
266	IO::AIO::nready	272	IO::AIO::nready
267	IO::AIO::npending	273	IO::AIO::npending
268		274
269	IO::AIO::sendfile $ofh, $ifh, $offset, $count	275	IO::AIO::sendfile $ofh, $ifh, $offset, $count
270	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
271	IO::AIO::madvise $scalar, $offset, $length, $advice	279	IO::AIO::madvise $scalar, $offset, $length, $advice
272	IO::AIO::mprotect $scalar, $offset, $length, $protect	280	IO::AIO::mprotect $scalar, $offset, $length, $protect
273	IO::AIO::munlock $scalar, $offset = 0, $length = undef	281	IO::AIO::munlock $scalar, $offset = 0, $length = undef
274	IO::AIO::munlockall	282	IO::AIO::munlockall
275		283
276	=head2 AIO REQUEST FUNCTIONS	284	=head2 API NOTES
277		285
278	All the C<aio_*> calls are more or less thin wrappers around the syscall	286	All the C<aio_*> calls are more or less thin wrappers around the syscall
279	with the same name (sans C<aio_>). The arguments are similar or identical,	287	with the same name (sans C<aio_>). The arguments are similar or identical,
280	and they all accept an additional (and optional) C<$callback> argument	288	and they all accept an additional (and optional) C<$callback> argument
281	which must be a code reference. This code reference will get called with	289	which must be a code reference. This code reference will be called after
282	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	290	the syscall has been executed in an asynchronous fashion. The results
283	perl, which usually delivers "false") as its sole argument after the given	291	of the request will be passed as arguments to the callback (and, if an
284	syscall has been executed asynchronously.	292	error occured, in C<$!>) - 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>.
285		298
286	All functions expecting a filehandle keep a copy of the filehandle	299	All functions expecting a filehandle keep a copy of the filehandle
287	internally until the request has finished.	300	internally until the request has finished.
288		301
289	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
290	further manipulation of those requests while they are in-flight.	303	further manipulation of those requests while they are in-flight.
291		304
292	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
293	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
294	request is being executed, the current working directory could have	307	current working directory could have changed. Alternatively, you can
295	changed. Alternatively, you can make sure that you never change the	308	make sure that you never change the current working directory anywhere
296	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
297	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.
298		313
299	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
300	in filenames you got from outside (command line, readdir etc.) without	315	in filenames you got from outside (command line, readdir etc.) without
301	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
302	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
303	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
304	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.
305		321
306	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
307	handles correctly whether it is set or not.	323	handles correctly whether it is set or not.
		324
		325	=head2 AIO REQUEST FUNCTIONS
308		326
309	=over 4	327	=over 4
310		328
311	=item $prev_pri = aioreq_pri [$pri]	329	=item $prev_pri = aioreq_pri [$pri]
312		330
…		…
394		412
395	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
396	free for reuse until the perl filehandle is closed.	414	free for reuse until the perl filehandle is closed.
397		415
398	=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".
399		437
400	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	438	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
401		439
402	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	440	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
403		441
…		…
611		649
612	Asynchronously unlink (delete) a file and call the callback with the	650	Asynchronously unlink (delete) a file and call the callback with the
613	result code.	651	result code.
614		652
615		653
616	=item aio_mknod $path, $mode, $dev, $callback->($status)	654	=item aio_mknod $pathname, $mode, $dev, $callback->($status)
617		655
618	[EXPERIMENTAL]	656	[EXPERIMENTAL]
619		657
620	Asynchronously create a device node (or fifo). See mknod(2).	658	Asynchronously create a device node (or fifo). See mknod(2).
621		659
622	The only (POSIX-) portable way of calling this function is:	660	The only (POSIX-) portable way of calling this function is:
623		661
624	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	662	aio_mknod $pathname, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
625		663
626	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
627	and functions.	665	and functions.
628		666
629	=item aio_link $srcpath, $dstpath, $callback->($status)	667	=item aio_link $srcpath, $dstpath, $callback->($status)
…		…
636		674
637	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
638	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.
639		677
640		678
641	=item aio_readlink $path, $callback->($link)	679	=item aio_readlink $pathname, $callback->($link)
642		680
643	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
644	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
645	callback.	683	callback.
646		684
647		685
		686	=item aio_realpath $pathname, $callback->($path)
		687
		688	Asynchronously make the path absolute and resolve any symlinks in
		689	C<$path>. The resulting path only consists of directories (Same as
		690	L<Cwd::realpath>).
		691
		692	This request can be used to get the absolute path of the current working
		693	directory by passing it a path of F<.> (a single dot).
		694
		695
648	=item aio_rename $srcpath, $dstpath, $callback->($status)	696	=item aio_rename $srcpath, $dstpath, $callback->($status)
649		697
650	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	698	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
651	rename(2) and call the callback with the result code.	699	rename(2) and call the callback with the result code.
652		700
…		…
674	array-ref with the filenames.	722	array-ref with the filenames.
675		723
676		724
677	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)	725	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
678		726
679	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune	727	Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to
680	behaviour and output format. In case of an error, C<$entries> will be	728	tune behaviour and output format. In case of an error, C<$entries> will be
681	C<undef>.	729	C<undef>.
682		730
683	The flags are a combination of the following constants, ORed together (the	731	The flags are a combination of the following constants, ORed together (the
684	flags will also be passed to the callback, possibly modified):	732	flags will also be passed to the callback, possibly modified):
685		733
…		…
732		780
733	=item IO::AIO::READDIR_FOUND_UNKNOWN	781	=item IO::AIO::READDIR_FOUND_UNKNOWN
734		782
735	This flag should not be set when calling C<aio_readdirx>. Instead, it	783	This flag should not be set when calling C<aio_readdirx>. Instead, it
736	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	784	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
737	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all	785	C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all
738	C<$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.
739		787
740	=back	788	=back
741		789
742		790
743	=item aio_load $path, $data, $callback->($status)	791	=item aio_load $pathname, $data, $callback->($status)
744		792
745	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
746	memory. Status is the same as with aio_read.	794	memory. Status is the same as with aio_read.
747		795
748	=cut	796	=cut
…		…
883	};	931	};
884		932
885	$grp	933	$grp
886	}	934	}
887		935
888	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	936	=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
889		937
890	Scans a directory (similar to C<aio_readdir>) but additionally tries to	938	Scans a directory (similar to C<aio_readdir>) but additionally tries to
891	efficiently separate the entries of directory C<$path> into two sets of	939	efficiently separate the entries of directory C<$path> into two sets of
892	names, directories you can recurse into (directories), and ones you cannot	940	names, directories you can recurse into (directories), and ones you cannot
893	recurse into (everything else, including symlinks to directories).	941	recurse into (everything else, including symlinks to directories).
…		…
924	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
925	currently) and likely non-directories (see C<aio_readdirx>). Then every	973	currently) and likely non-directories (see C<aio_readdirx>). Then every
926	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,
927	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
928	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
929	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
930	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
931	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
932	the filetype information on readdir.	980	the filetype information on readdir.
933		981
934	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
…		…
950		998
951	my $grp = aio_group $cb;	999	my $grp = aio_group $cb;
952		1000
953	$maxreq = 4 if $maxreq <= 0;	1001	$maxreq = 4 if $maxreq <= 0;
954		1002
955	# stat once	1003	# get a wd object
956	aioreq_pri $pri;	1004	aioreq_pri $pri;
957	add $grp aio_stat $path, sub {	1005	add $grp aio_wd $path, sub {
		1006	$_[0]
958	return $grp->result () if $_[0];	1007	or return $grp->result ();
959	my $now = time;
960	my $hash1 = join ":", (stat _)[0,1,3,7,9];
961		1008
962	# read the directory entries	1009	my $wd = [shift, "."];
		1010
		1011	# stat once
963	aioreq_pri $pri;	1012	aioreq_pri $pri;
964	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {	1013	add $grp aio_stat $wd, sub {
965	my $entries = shift
966	or return $grp->result ();	1014	return $grp->result () if $_[0];
		1015	my $now = time;
		1016	my $hash1 = join ":", (stat _)[0,1,3,7,9];
967		1017
968	# stat the dir another time	1018	# read the directory entries
969	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;
970	add $grp aio_stat $path, sub {	1026	add $grp aio_stat $wd, sub {
971	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1027	my $hash2 = join ":", (stat _)[0,1,3,7,9];
972		1028
973	my $ndirs;	1029	my $ndirs;
974		1030
975	# take the slow route if anything looks fishy	1031	# take the slow route if anything looks fishy
976	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	1032	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
977	$ndirs = -1;	1033	$ndirs = -1;
978	} else {	1034	} else {
979	# if nlink == 2, we are finished	1035	# if nlink == 2, we are finished
980	# for non-posix-fs's, we rely on nlink < 2	1036	# for non-posix-fs's, we rely on nlink < 2
981	$ndirs = (stat _)[3] - 2	1037	$ndirs = (stat _)[3] - 2
982	or return $grp->result ([], $entries);	1038	or return $grp->result ([], $entries);
983	}	1039	}
984		1040
985	my (@dirs, @nondirs);	1041	my (@dirs, @nondirs);
986		1042
987	my $statgrp = add $grp aio_group sub {	1043	my $statgrp = add $grp aio_group sub {
988	$grp->result (\@dirs, \@nondirs);	1044	$grp->result (\@dirs, \@nondirs);
989	};	1045	};
990		1046
991	limit $statgrp $maxreq;	1047	limit $statgrp $maxreq;
992	feed $statgrp sub {	1048	feed $statgrp sub {
993	return unless @$entries;	1049	return unless @$entries;
994	my $entry = shift @$entries;	1050	my $entry = shift @$entries;
995		1051
996	aioreq_pri $pri;	1052	aioreq_pri $pri;
		1053	$wd->[1] = "$entry/.";
997	add $statgrp aio_stat "$path/$entry/.", sub {	1054	add $statgrp aio_stat $wd, sub {
998	if ($_[0] < 0) {	1055	if ($_[0] < 0) {
999	push @nondirs, $entry;	1056	push @nondirs, $entry;
1000	} else {	1057	} else {
1001	# need to check for real directory	1058	# need to check for real directory
1002	aioreq_pri $pri;	1059	aioreq_pri $pri;
		1060	$wd->[1] = $entry;
1003	add $statgrp aio_lstat "$path/$entry", sub {	1061	add $statgrp aio_lstat $wd, sub {
1004	if (-d _) {	1062	if (-d _) {
1005	push @dirs, $entry;	1063	push @dirs, $entry;
1006		1064
1007	unless (--$ndirs) {	1065	unless (--$ndirs) {
1008	push @nondirs, @$entries;	1066	push @nondirs, @$entries;
1009	feed $statgrp;	1067	feed $statgrp;
		1068	}
		1069	} else {
		1070	push @nondirs, $entry;
1010	}	1071	}
1011	} else {
1012	push @nondirs, $entry;
1013	}	1072	}
1014	}	1073	}
1015	}	1074	};
1016	};	1075	};
1017	};	1076	};
1018	};	1077	};
1019	};	1078	};
1020	};	1079	};
1021		1080
1022	$grp	1081	$grp
1023	}	1082	}
1024		1083
1025	=item aio_rmtree $path, $callback->($status)	1084	=item aio_rmtree $pathname, $callback->($status)
1026		1085
1027	Delete a directory tree starting (and including) C<$path>, return the	1086	Delete a directory tree starting (and including) C<$path>, return the
1028	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
1029	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
1030	everything else.	1089	everything else.
…		…
1072	callback with the fdatasync result code.	1131	callback with the fdatasync result code.
1073		1132
1074	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
1075	detected, it will be emulated by calling C<fsync> instead.	1134	detected, it will be emulated by calling C<fsync> instead.
1076		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
1077	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	1143	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
1078		1144
1079	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>
1080	to disk (but NOT the metadata), by calling the Linux-specific	1146	to disk (but NOT the metadata), by calling the Linux-specific
1081	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
…		…
1084	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>,
1085	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and	1151	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1086	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
1087	manpage for details.	1153	manpage for details.
1088		1154
1089	=item aio_pathsync $path, $callback->($status)	1155	=item aio_pathsync $pathname, $callback->($status)
1090		1156
1091	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
1092	composite request intended to sync directories after directory operations	1158	composite request intended to sync directories after directory operations
1093	(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
1094	specific effect, but usually it makes sure that directory changes get	1160	specific effect, but usually it makes sure that directory changes get
…		…
1191		1257
1192	Example: asynchronously lock all current and future pages into memory.	1258	Example: asynchronously lock all current and future pages into memory.
1193		1259
1194	aio_mlockall IO::AIO::MCL_FUTURE;	1260	aio_mlockall IO::AIO::MCL_FUTURE;
1195		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
1196	=item aio_group $callback->(...)	1302	=item aio_group $callback->(...)
1197		1303
1198	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
1199	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
1200	many requests into a single, composite, request with a definite callback	1306	many requests into a single, composite, request with a definite callback
…		…
1236	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
1237	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
1238	except to put your application under artificial I/O pressure.	1344	except to put your application under artificial I/O pressure.
1239		1345
1240	=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
1241		1466
1242	=head2 IO::AIO::REQ CLASS	1467	=head2 IO::AIO::REQ CLASS
1243		1468
1244	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
1245	called in non-void context.	1470	called in non-void context.
…		…
1363		1588
1364	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
1365	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,
1366	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,
1367	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,
1368	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>
1369	delaying any later requests for a long time.	1594	requests, delaying any later requests for a long time.
1370		1595
1371	To avoid this, and allow incremental generation of requests, you can	1596	To avoid this, and allow incremental generation of requests, you can
1372	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
1373	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>,
1374	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
…		…
1653		1878
1654	=item IO::AIO::fadvise $fh, $offset, $len, $advice	1879	=item IO::AIO::fadvise $fh, $offset, $len, $advice
1655		1880
1656	Simply calls the C<posix_fadvise> function (see its	1881	Simply calls the C<posix_fadvise> function (see its
1657	manpage for details). The following advice constants are	1882	manpage for details). The following advice constants are
1658	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,	1883	available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1659	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,	1884	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1660	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.	1885	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1661		1886
1662	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
1663	ENOSYS, otherwise the return value of C<posix_fadvise>.	1888	ENOSYS, otherwise the return value of C<posix_fadvise>.
1664		1889
1665	=item IO::AIO::madvise $scalar, $offset, $len, $advice	1890	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1666		1891
1667	Simply calls the C<posix_madvise> function (see its	1892	Simply calls the C<posix_madvise> function (see its
1668	manpage for details). The following advice constants are	1893	manpage for details). The following advice constants are
1669	avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	1894	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1670	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>.
1671		1896
1672	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
1673	ENOSYS, otherwise the return value of C<posix_madvise>.	1898	ENOSYS, otherwise the return value of C<posix_madvise>.
1674		1899
1675	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	1900	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1676		1901
1677	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
1678	$scalar (see its manpage for details). The following protect	1903	$scalar (see its manpage for details). The following protect
1679	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>,
1680	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	1905	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1681		1906
1682	On systems that do not implement C<mprotect>, this function returns	1907	On systems that do not implement C<mprotect>, this function returns
1683	ENOSYS, otherwise the return value of C<mprotect>.	1908	ENOSYS, otherwise the return value of C<mprotect>.
1684		1909
…		…
1746	Calls the C<munlockall> function.	1971	Calls the C<munlockall> function.
1747		1972
1748	On systems that do not implement C<munlockall>, this function returns	1973	On systems that do not implement C<munlockall>, this function returns
1749	ENOSYS, otherwise the return value of C<munlockall>.	1974	ENOSYS, otherwise the return value of C<munlockall>.
1750		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<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		1980	should be the file offset.
		1981
		1982	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		1983	silently corrupt the data in this case.
		1984
		1985	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		1986	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		1987	C<IO::AIO::SPLICE_F_GIFT>.
		1988
		1989	See the C<splice(2)> manpage for details.
		1990
		1991	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		1992
		1993	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
		1994	description for C<IO::AIO::splice> above for details.
		1995
1751	=back	1996	=back
1752		1997
1753	=cut	1998	=cut
1754		1999
1755	min_parallel 8;	2000	min_parallel 8;
…		…
1792	=head2 FORK BEHAVIOUR	2037	=head2 FORK BEHAVIOUR
1793		2038
1794	Usage of pthreads in a program changes the semantics of fork	2039	Usage of pthreads in a program changes the semantics of fork
1795	considerably. Specifically, only async-safe functions can be called after	2040	considerably. Specifically, only async-safe functions can be called after
1796	fork. Perl doesn't know about this, so in general, you cannot call fork	2041	fork. Perl doesn't know about this, so in general, you cannot call fork
1797	with defined behaviour in perl. IO::AIO uses pthreads, so this applies,	2042	with defined behaviour in perl if pthreads are involved. IO::AIO uses
1798	but many other extensions and (for inexplicable reasons) perl itself often	2043	pthreads, so this applies, but many other extensions and (for inexplicable
1799	is linked against pthreads, so this limitation applies.	2044	reasons) perl itself often is linked against pthreads, so this limitation
		2045	applies to quite a lot of perls.
1800		2046
1801	Some operating systems have extensions that allow safe use of fork, and	2047	This module no longer tries to fight your OS, or POSIX. That means IO::AIO
1802	this module should do "the right thing" on those, and tries on others. At	2048	only works in the process that loaded it. Forking is fully supported, but
1803	the time of this writing (2011) only GNU/Linux supports these extensions	2049	using IO::AIO in the child is not.
1804	to POSIX.	2050
		2051	You might get around by not I<using> IO::AIO before (or after)
		2052	forking. You could also try to call the L<IO::AIO::reinit> function in the
		2053	child:
		2054
		2055	=over 4
		2056
		2057	=item IO::AIO::reinit
		2058
		2059	Abandons all current requests and I/O threads and simply reinitialises all
		2060	data structures. This is not an operation supported by any standards, but
		2061	happens to work on GNU/Linux and some newer BSD systems.
		2062
		2063	The only reasonable use for this function is to call it after forking, if
		2064	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
		2065	the process will result in undefined behaviour. Calling it at any time
		2066	will also result in any undefined (by POSIX) behaviour.
		2067
		2068	=back
1805		2069
1806	=head2 MEMORY USAGE	2070	=head2 MEMORY USAGE
1807		2071
1808	Per-request usage:	2072	Per-request usage:
1809		2073

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.199 by root, Wed Jun 29 12:46:36 2011 UTC vs. Revision 1.227 by root, Tue May 29 03:58:02 2012 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.199 by root, Wed Jun 29 12:46:36 2011 UTC vs.
Revision 1.227 by root, Tue May 29 03:58:02 2012 UTC