[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 1.225 by root, Tue Apr 10 05:01:33 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->(...)
…		…
271	IO::AIO::madvise $scalar, $offset, $length, $advice	277	IO::AIO::madvise $scalar, $offset, $length, $advice
272	IO::AIO::mprotect $scalar, $offset, $length, $protect	278	IO::AIO::mprotect $scalar, $offset, $length, $protect
273	IO::AIO::munlock $scalar, $offset = 0, $length = undef	279	IO::AIO::munlock $scalar, $offset = 0, $length = undef
274	IO::AIO::munlockall	280	IO::AIO::munlockall
275		281
276	=head2 AIO REQUEST FUNCTIONS	282	=head2 API NOTES
277		283
278	All the C<aio_*> calls are more or less thin wrappers around the syscall	284	All the C<aio_*> calls are more or less thin wrappers around the syscall
279	with the same name (sans C<aio_>). The arguments are similar or identical,	285	with the same name (sans C<aio_>). The arguments are similar or identical,
280	and they all accept an additional (and optional) C<$callback> argument	286	and they all accept an additional (and optional) C<$callback> argument
281	which must be a code reference. This code reference will get called with	287	which must be a code reference. This code reference will be called after
282	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	288	the syscall has been executed in an asynchronous fashion. The results
283	perl, which usually delivers "false") as its sole argument after the given	289	of the request will be passed as arguments to the callback (and, if an
284	syscall has been executed asynchronously.	290	error occured, in C<$!>) - for most requests the syscall return code (e.g.
		291	most syscalls return C<-1> on error, unlike perl, which usually delivers
		292	"false").
		293
		294	Some requests (such as C<aio_readdir>) pass the actual results and
		295	communicate failures by passing C<undef>.
285		296
286	All functions expecting a filehandle keep a copy of the filehandle	297	All functions expecting a filehandle keep a copy of the filehandle
287	internally until the request has finished.	298	internally until the request has finished.
288		299
289	All functions return request objects of type L<IO::AIO::REQ> that allow	300	All functions return request objects of type L<IO::AIO::REQ> that allow
290	further manipulation of those requests while they are in-flight.	301	further manipulation of those requests while they are in-flight.
291		302
292	The pathnames you pass to these routines I<must> be absolute and	303	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	304	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	305	current working directory could have changed. Alternatively, you can
295	changed. Alternatively, you can make sure that you never change the	306	make sure that you never change the current working directory anywhere
296	current working directory anywhere in the program and then use relative	307	in the program and then use relative paths. You can also take advantage
297	paths.	308	of IO::AIOs working directory abstraction, that lets you specify paths
		309	relative to some previously-opened "working directory object" - see the
		310	description of the C<IO::AIO::WD> class later in this document.
298		311
299	To encode pathnames as octets, either make sure you either: a) always pass	312	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	313	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	314	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	315	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)	316	effect in the user environment, d) use Glib::filename_from_unicode on
304	use something else to ensure your scalar has the correct contents.	317	unicode filenames or e) use something else to ensure your scalar has the
		318	correct contents.
305		319
306	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	320	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
307	handles correctly whether it is set or not.	321	handles correctly whether it is set or not.
		322
		323	=head2 AIO REQUEST FUNCTIONS
308		324
309	=over 4	325	=over 4
310		326
311	=item $prev_pri = aioreq_pri [$pri]	327	=item $prev_pri = aioreq_pri [$pri]
312		328
…		…
394		410
395	Or in other words: the file descriptor will be closed, but it will not be	411	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.	412	free for reuse until the perl filehandle is closed.
397		413
398	=cut	414	=cut
		415
		416	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		417
		418	Seeks the filehandle to the new C<$offset>, similarly to perl's
		419	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		420	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		421	C<IO::AIO::SEEK_END>).
		422
		423	The resulting absolute offset will be passed to the callback, or C<-1> in
		424	case of an error.
		425
		426	In theory, the C<$whence> constants could be different than the
		427	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		428	so don't panic.
		429
		430	As a GNU/Linux (and maybe Solaris) extension, also the constants
		431	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		432	could be found. No guarantees about suitability for use in C<aio_seek> or
		433	Perl's C<sysseek> can be made though, although I would naively assume they
		434	"just work".
399		435
400	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	436	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
401		437
402	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	438	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
403		439
…		…
611		647
612	Asynchronously unlink (delete) a file and call the callback with the	648	Asynchronously unlink (delete) a file and call the callback with the
613	result code.	649	result code.
614		650
615		651
616	=item aio_mknod $path, $mode, $dev, $callback->($status)	652	=item aio_mknod $pathname, $mode, $dev, $callback->($status)
617		653
618	[EXPERIMENTAL]	654	[EXPERIMENTAL]
619		655
620	Asynchronously create a device node (or fifo). See mknod(2).	656	Asynchronously create a device node (or fifo). See mknod(2).
621		657
622	The only (POSIX-) portable way of calling this function is:	658	The only (POSIX-) portable way of calling this function is:
623		659
624	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	660	aio_mknod $pathname, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
625		661
626	See C<aio_stat> for info about some potentially helpful extra constants	662	See C<aio_stat> for info about some potentially helpful extra constants
627	and functions.	663	and functions.
628		664
629	=item aio_link $srcpath, $dstpath, $callback->($status)	665	=item aio_link $srcpath, $dstpath, $callback->($status)
…		…
636		672
637	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	673	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
638	the path C<$dstpath> and call the callback with the result code.	674	the path C<$dstpath> and call the callback with the result code.
639		675
640		676
641	=item aio_readlink $path, $callback->($link)	677	=item aio_readlink $pathname, $callback->($link)
642		678
643	Asynchronously read the symlink specified by C<$path> and pass it to	679	Asynchronously read the symlink specified by C<$path> and pass it to
644	the callback. If an error occurs, nothing or undef gets passed to the	680	the callback. If an error occurs, nothing or undef gets passed to the
645	callback.	681	callback.
646		682
647		683
		684	=item aio_realpath $pathname, $callback->($path)
		685
		686	Asynchronously make the path absolute and resolve any symlinks in
		687	C<$path>. The resulting path only consists of directories (Same as
		688	L<Cwd::realpath>).
		689
		690	This request can be used to get the absolute path of the current working
		691	directory by passing it a path of F<.> (a single dot).
		692
		693
648	=item aio_rename $srcpath, $dstpath, $callback->($status)	694	=item aio_rename $srcpath, $dstpath, $callback->($status)
649		695
650	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	696	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
651	rename(2) and call the callback with the result code.	697	rename(2) and call the callback with the result code.
652		698
…		…
674	array-ref with the filenames.	720	array-ref with the filenames.
675		721
676		722
677	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)	723	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
678		724
679	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune	725	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	726	tune behaviour and output format. In case of an error, C<$entries> will be
681	C<undef>.	727	C<undef>.
682		728
683	The flags are a combination of the following constants, ORed together (the	729	The flags are a combination of the following constants, ORed together (the
684	flags will also be passed to the callback, possibly modified):	730	flags will also be passed to the callback, possibly modified):
685		731
…		…
732		778
733	=item IO::AIO::READDIR_FOUND_UNKNOWN	779	=item IO::AIO::READDIR_FOUND_UNKNOWN
734		780
735	This flag should not be set when calling C<aio_readdirx>. Instead, it	781	This flag should not be set when calling C<aio_readdirx>. Instead, it
736	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	782	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
737	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all	783	C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all
738	C<$type>'s are known, which can be used to speed up some algorithms.	784	C<$type>'s are known, which can be used to speed up some algorithms.
739		785
740	=back	786	=back
741		787
742		788
743	=item aio_load $path, $data, $callback->($status)	789	=item aio_load $pathname, $data, $callback->($status)
744		790
745	This is a composite request that tries to fully load the given file into	791	This is a composite request that tries to fully load the given file into
746	memory. Status is the same as with aio_read.	792	memory. Status is the same as with aio_read.
747		793
748	=cut	794	=cut
…		…
883	};	929	};
884		930
885	$grp	931	$grp
886	}	932	}
887		933
888	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	934	=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
889		935
890	Scans a directory (similar to C<aio_readdir>) but additionally tries to	936	Scans a directory (similar to C<aio_readdir>) but additionally tries to
891	efficiently separate the entries of directory C<$path> into two sets of	937	efficiently separate the entries of directory C<$path> into two sets of
892	names, directories you can recurse into (directories), and ones you cannot	938	names, directories you can recurse into (directories), and ones you cannot
893	recurse into (everything else, including symlinks to directories).	939	recurse into (everything else, including symlinks to directories).
…		…
924	Then entries will be sorted into likely directories a non-initial dot	970	Then entries will be sorted into likely directories a non-initial dot
925	currently) and likely non-directories (see C<aio_readdirx>). Then every	971	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,	972	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	973	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	974	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	975	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	976	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	977	data (e.g. ext2fs filetype feature), even on systems that cannot return
932	the filetype information on readdir.	978	the filetype information on readdir.
933		979
934	If the known number of directories (link count - 2) has been reached, the	980	If the known number of directories (link count - 2) has been reached, the
…		…
950		996
951	my $grp = aio_group $cb;	997	my $grp = aio_group $cb;
952		998
953	$maxreq = 4 if $maxreq <= 0;	999	$maxreq = 4 if $maxreq <= 0;
954		1000
955	# stat once	1001	# get a wd object
956	aioreq_pri $pri;	1002	aioreq_pri $pri;
957	add $grp aio_stat $path, sub {	1003	add $grp aio_wd $path, sub {
		1004	$_[0]
958	return $grp->result () if $_[0];	1005	or return $grp->result ();
959	my $now = time;
960	my $hash1 = join ":", (stat _)[0,1,3,7,9];
961		1006
962	# read the directory entries	1007	my $wd = [shift, "."];
		1008
		1009	# stat once
963	aioreq_pri $pri;	1010	aioreq_pri $pri;
964	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {	1011	add $grp aio_stat $wd, sub {
965	my $entries = shift
966	or return $grp->result ();	1012	return $grp->result () if $_[0];
		1013	my $now = time;
		1014	my $hash1 = join ":", (stat _)[0,1,3,7,9];
967		1015
968	# stat the dir another time	1016	# read the directory entries
969	aioreq_pri $pri;	1017	aioreq_pri $pri;
		1018	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {
		1019	my $entries = shift
		1020	or return $grp->result ();
		1021
		1022	# stat the dir another time
		1023	aioreq_pri $pri;
970	add $grp aio_stat $path, sub {	1024	add $grp aio_stat $wd, sub {
971	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1025	my $hash2 = join ":", (stat _)[0,1,3,7,9];
972		1026
973	my $ndirs;	1027	my $ndirs;
974		1028
975	# take the slow route if anything looks fishy	1029	# take the slow route if anything looks fishy
976	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	1030	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
977	$ndirs = -1;	1031	$ndirs = -1;
978	} else {	1032	} else {
979	# if nlink == 2, we are finished	1033	# if nlink == 2, we are finished
980	# for non-posix-fs's, we rely on nlink < 2	1034	# for non-posix-fs's, we rely on nlink < 2
981	$ndirs = (stat _)[3] - 2	1035	$ndirs = (stat _)[3] - 2
982	or return $grp->result ([], $entries);	1036	or return $grp->result ([], $entries);
983	}	1037	}
984		1038
985	my (@dirs, @nondirs);	1039	my (@dirs, @nondirs);
986		1040
987	my $statgrp = add $grp aio_group sub {	1041	my $statgrp = add $grp aio_group sub {
988	$grp->result (\@dirs, \@nondirs);	1042	$grp->result (\@dirs, \@nondirs);
989	};	1043	};
990		1044
991	limit $statgrp $maxreq;	1045	limit $statgrp $maxreq;
992	feed $statgrp sub {	1046	feed $statgrp sub {
993	return unless @$entries;	1047	return unless @$entries;
994	my $entry = shift @$entries;	1048	my $entry = shift @$entries;
995		1049
996	aioreq_pri $pri;	1050	aioreq_pri $pri;
		1051	$wd->[1] = "$entry/.";
997	add $statgrp aio_stat "$path/$entry/.", sub {	1052	add $statgrp aio_stat $wd, sub {
998	if ($_[0] < 0) {	1053	if ($_[0] < 0) {
999	push @nondirs, $entry;	1054	push @nondirs, $entry;
1000	} else {	1055	} else {
1001	# need to check for real directory	1056	# need to check for real directory
1002	aioreq_pri $pri;	1057	aioreq_pri $pri;
		1058	$wd->[1] = $entry;
1003	add $statgrp aio_lstat "$path/$entry", sub {	1059	add $statgrp aio_lstat $wd, sub {
1004	if (-d _) {	1060	if (-d _) {
1005	push @dirs, $entry;	1061	push @dirs, $entry;
1006		1062
1007	unless (--$ndirs) {	1063	unless (--$ndirs) {
1008	push @nondirs, @$entries;	1064	push @nondirs, @$entries;
1009	feed $statgrp;	1065	feed $statgrp;
		1066	}
		1067	} else {
		1068	push @nondirs, $entry;
1010	}	1069	}
1011	} else {
1012	push @nondirs, $entry;
1013	}	1070	}
1014	}	1071	}
1015	}	1072	};
1016	};	1073	};
1017	};	1074	};
1018	};	1075	};
1019	};	1076	};
1020	};	1077	};
1021		1078
1022	$grp	1079	$grp
1023	}	1080	}
1024		1081
1025	=item aio_rmtree $path, $callback->($status)	1082	=item aio_rmtree $pathname, $callback->($status)
1026		1083
1027	Delete a directory tree starting (and including) C<$path>, return the	1084	Delete a directory tree starting (and including) C<$path>, return the
1028	status of the final C<rmdir> only. This is a composite request that	1085	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	1086	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1030	everything else.	1087	everything else.
…		…
1072	callback with the fdatasync result code.	1129	callback with the fdatasync result code.
1073		1130
1074	If this call isn't available because your OS lacks it or it couldn't be	1131	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.	1132	detected, it will be emulated by calling C<fsync> instead.
1076		1133
		1134	=item aio_syncfs $fh, $callback->($status)
		1135
		1136	Asynchronously call the syncfs syscall to sync the filesystem associated
		1137	to the given filehandle and call the callback with the syncfs result
		1138	code. If syncfs is not available, calls sync(), but returns C<-1> and sets
		1139	errno to C<ENOSYS> nevertheless.
		1140
1077	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	1141	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
1078		1142
1079	Sync the data portion of the file specified by C<$offset> and C<$length>	1143	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	1144	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	1145	sync_file_range call. If sync_file_range is not available or it returns
…		…
1084	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,	1148	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
1085	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and	1149	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1086	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range	1150	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
1087	manpage for details.	1151	manpage for details.
1088		1152
1089	=item aio_pathsync $path, $callback->($status)	1153	=item aio_pathsync $pathname, $callback->($status)
1090		1154
1091	This request tries to open, fsync and close the given path. This is a	1155	This request tries to open, fsync and close the given path. This is a
1092	composite request intended to sync directories after directory operations	1156	composite request intended to sync directories after directory operations
1093	(E.g. rename). This might not work on all operating systems or have any	1157	(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	1158	specific effect, but usually it makes sure that directory changes get
…		…
1191		1255
1192	Example: asynchronously lock all current and future pages into memory.	1256	Example: asynchronously lock all current and future pages into memory.
1193		1257
1194	aio_mlockall IO::AIO::MCL_FUTURE;	1258	aio_mlockall IO::AIO::MCL_FUTURE;
1195		1259
		1260	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1261
		1262	Queries the extents of the given file (by calling the Linux FIEMAP ioctl,
		1263	see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the
		1264	C<ioctl> is not available on your OS, then this rquiest will fail with
		1265	C<ENOSYS>.
		1266
		1267	C<$start> is the starting offset to query extents for, C<$length> is the
		1268	size of the range to query - if it is C<undef>, then the whole file will
		1269	be queried.
		1270
		1271	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1272	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1273	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1274	the data portion.
		1275
		1276	C<$count> is the maximum number of extent records to return. If it is
		1277	C<undef>, then IO::AIO queries all extents of the file. As a very special
		1278	case, if it is C<0>, then the callback receives the number of extents
		1279	instead of the extents themselves.
		1280
		1281	If an error occurs, the callback receives no arguments. The special
		1282	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1283
		1284	Otherwise, the callback receives an array reference with extent
		1285	structures. Each extent structure is an array reference itself, with the
		1286	following members:
		1287
		1288	[$logical, $physical, $length, $flags]
		1289
		1290	Flags is any combination of the following flag values (typically either C<0>
		1291	or C<IO::AIO::FIEMAP_EXTENT_LAST>):
		1292
		1293	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1294	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1295	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1296	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1297	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1298	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1299
1196	=item aio_group $callback->(...)	1300	=item aio_group $callback->(...)
1197		1301
1198	This is a very special aio request: Instead of doing something, it is a	1302	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	1303	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	1304	many requests into a single, composite, request with a definite callback
…		…
1236	like sleep and file handle readable/writable, the overhead this creates is	1340	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	1341	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.	1342	except to put your application under artificial I/O pressure.
1239		1343
1240	=back	1344	=back
		1345
		1346
		1347	=head2 IO::AIO::WD - multiple working directories
		1348
		1349	Your process only has one current working directory, which is used by all
		1350	threads. This makes it hard to use relative paths (some other component
		1351	could call C<chdir> at any time, and it is hard to control when the path
		1352	will be used by IO::AIO).
		1353
		1354	One solution for this is to always use absolute paths. This usually works,
		1355	but can be quite slow (the kernel has to walk the whole path on every
		1356	access), and can also be a hassle to implement.
		1357
		1358	Newer POSIX systems have a number of functions (openat, fdopendir,
		1359	futimensat and so on) that make it possible to specify working directories
		1360	per operation.
		1361
		1362	For portability, and because the clowns who "designed", or shall I write,
		1363	perpetrated this new interface were obviously half-drunk, this abstraction
		1364	cannot be perfect, though.
		1365
		1366	IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD
		1367	object. This object stores the canonicalised, absolute version of the
		1368	path, and on systems that allow it, also a directory file descriptor.
		1369
		1370	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
		1371	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
		1372	object and a pathname instead (or the IO::AIO::WD object alone, which
		1373	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
		1374	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
		1375	to that IO::AIO::WD object.
		1376
		1377	For example, to get a wd object for F</etc> and then stat F<passwd>
		1378	inside, you would write:
		1379
		1380	aio_wd "/etc", sub {
		1381	my $etcdir = shift;
		1382
		1383	# although $etcdir can be undef on error, there is generally no reason
		1384	# to check for errors here, as aio_stat will fail with ENOENT
		1385	# when $etcdir is undef.
		1386
		1387	aio_stat [$etcdir, "passwd"], sub {
		1388	# yay
		1389	};
		1390	};
		1391
		1392	That C<aio_wd> is a request and not a normal function shows that creating
		1393	an IO::AIO::WD object is itself a potentially blocking operation, which is
		1394	why it is done asynchronously.
		1395
		1396	To stat the directory obtained with C<aio_wd> above, one could write
		1397	either of the following three request calls:
		1398
		1399	aio_lstat "/etc" , sub { ... # pathname as normal string
		1400	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1401	aio_lstat $wd , sub { ... # shorthand for the previous
		1402
		1403	As with normal pathnames, IO::AIO keeps a copy of the working directory
		1404	object and the pathname string, so you could write the following without
		1405	causing any issues due to C<$path> getting reused:
		1406
		1407	my $path = [$wd, undef];
		1408
		1409	for my $name (qw(abc def ghi)) {
		1410	$path->[1] = $name;
		1411	aio_stat $path, sub {
		1412	# ...
		1413	};
		1414	}
		1415
		1416	There are some caveats: when directories get renamed (or deleted), the
		1417	pathname string doesn't change, so will point to the new directory (or
		1418	nowhere at all), while the directory fd, if available on the system,
		1419	will still point to the original directory. Most functions accepting a
		1420	pathname will use the directory fd on newer systems, and the string on
		1421	older systems. Some functions (such as realpath) will always rely on the
		1422	string form of the pathname.
		1423
		1424	So this fucntionality is mainly useful to get some protection against
		1425	C<chdir>, to easily get an absolute path out of a relative path for future
		1426	reference, and to speed up doing many operations in the same directory
		1427	(e.g. when stat'ing all files in a directory).
		1428
		1429	The following functions implement this working directory abstraction:
		1430
		1431	=over 4
		1432
		1433	=item aio_wd $pathname, $callback->($wd)
		1434
		1435	Asynchonously canonicalise the given pathname and convert it to an
		1436	IO::AIO::WD object representing it. If possible and supported on the
		1437	system, also open a directory fd to speed up pathname resolution relative
		1438	to this working directory.
		1439
		1440	If something goes wrong, then C<undef> is passwd to the callback instead
		1441	of a working directory object and C<$!> is set appropriately. Since
		1442	passing C<undef> as working directory component of a pathname fails the
		1443	request with C<ENOENT>, there is often no need for error checking in the
		1444	C<aio_wd> callback, as future requests using the value will fail in the
		1445	expected way.
		1446
		1447	If this call isn't available because your OS lacks it or it couldn't be
		1448	detected, it will be emulated by calling C<fsync> instead.
		1449
		1450	=item IO::AIO::CWD
		1451
		1452	This is a compiletime constant (object) that represents the process
		1453	current working directory.
		1454
		1455	Specifying this object as working directory object for a pathname is as
		1456	if the pathname would be specified directly, without a directory object,
		1457	e.g., these calls are functionally identical:
		1458
		1459	aio_stat "somefile", sub { ... };
		1460	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
		1461
		1462	=back
		1463
1241		1464
1242	=head2 IO::AIO::REQ CLASS	1465	=head2 IO::AIO::REQ CLASS
1243		1466
1244	All non-aggregate C<aio_*> functions return an object of this class when	1467	All non-aggregate C<aio_*> functions return an object of this class when
1245	called in non-void context.	1468	called in non-void context.
…		…
1363		1586
1364	Sets a feeder/generator on this group: every group can have an attached	1587	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,	1588	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,	1589	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,	1590	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,	1591	C<aio_scandir> might generate hundreds of thousands of C<aio_stat>
1369	delaying any later requests for a long time.	1592	requests, delaying any later requests for a long time.
1370		1593
1371	To avoid this, and allow incremental generation of requests, you can	1594	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	1595	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>,	1596	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	1597	below) requests active in the group itself and is expected to queue more
…		…
1653		1876
1654	=item IO::AIO::fadvise $fh, $offset, $len, $advice	1877	=item IO::AIO::fadvise $fh, $offset, $len, $advice
1655		1878
1656	Simply calls the C<posix_fadvise> function (see its	1879	Simply calls the C<posix_fadvise> function (see its
1657	manpage for details). The following advice constants are	1880	manpage for details). The following advice constants are
1658	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,	1881	available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1659	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,	1882	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1660	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.	1883	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1661		1884
1662	On systems that do not implement C<posix_fadvise>, this function returns	1885	On systems that do not implement C<posix_fadvise>, this function returns
1663	ENOSYS, otherwise the return value of C<posix_fadvise>.	1886	ENOSYS, otherwise the return value of C<posix_fadvise>.
1664		1887
1665	=item IO::AIO::madvise $scalar, $offset, $len, $advice	1888	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1666		1889
1667	Simply calls the C<posix_madvise> function (see its	1890	Simply calls the C<posix_madvise> function (see its
1668	manpage for details). The following advice constants are	1891	manpage for details). The following advice constants are
1669	avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	1892	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>.	1893	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
1671		1894
1672	On systems that do not implement C<posix_madvise>, this function returns	1895	On systems that do not implement C<posix_madvise>, this function returns
1673	ENOSYS, otherwise the return value of C<posix_madvise>.	1896	ENOSYS, otherwise the return value of C<posix_madvise>.
1674		1897
1675	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	1898	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1676		1899
1677	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	1900	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1678	$scalar (see its manpage for details). The following protect	1901	$scalar (see its manpage for details). The following protect
1679	constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	1902	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1680	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	1903	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1681		1904
1682	On systems that do not implement C<mprotect>, this function returns	1905	On systems that do not implement C<mprotect>, this function returns
1683	ENOSYS, otherwise the return value of C<mprotect>.	1906	ENOSYS, otherwise the return value of C<mprotect>.
1684		1907
…		…
1746	Calls the C<munlockall> function.	1969	Calls the C<munlockall> function.
1747		1970
1748	On systems that do not implement C<munlockall>, this function returns	1971	On systems that do not implement C<munlockall>, this function returns
1749	ENOSYS, otherwise the return value of C<munlockall>.	1972	ENOSYS, otherwise the return value of C<munlockall>.
1750		1973
		1974	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		1975
		1976	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		1977	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		1978	should be the file offset.
		1979
		1980	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		1981	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		1982	C<IO::AIO::SPLICE_F_GIFT>.
		1983
		1984	See the C<splice(2)> manpage for details.
		1985
		1986	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		1987
		1988	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
		1989	description for C<IO::AIO::splice> above for details.
		1990
1751	=back	1991	=back
1752		1992
1753	=cut	1993	=cut
1754		1994
1755	min_parallel 8;	1995	min_parallel 8;
…		…
1792	=head2 FORK BEHAVIOUR	2032	=head2 FORK BEHAVIOUR
1793		2033
1794	Usage of pthreads in a program changes the semantics of fork	2034	Usage of pthreads in a program changes the semantics of fork
1795	considerably. Specifically, only async-safe functions can be called after	2035	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	2036	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,	2037	with defined behaviour in perl if pthreads are involved. IO::AIO uses
1798	but many other extensions and (for inexplicable reasons) perl itself often	2038	pthreads, so this applies, but many other extensions and (for inexplicable
1799	is linked against pthreads, so this limitation applies.	2039	reasons) perl itself often is linked against pthreads, so this limitation
		2040	applies to quite a lot of perls.
1800		2041
1801	Some operating systems have extensions that allow safe use of fork, and	2042	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	2043	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	2044	using IO::AIO in the child is not.
1804	to POSIX.	2045
		2046	You might get around by not I<using> IO::AIO before (or after)
		2047	forking. You could also try to call the L<IO::AIO::reinit> function in the
		2048	child:
		2049
		2050	=over 4
		2051
		2052	=item IO::AIO::reinit
		2053
		2054	Abandons all current requests and I/O threads and simply reinitialises all
		2055	data structures. This is not an operation supported by any standards, but
		2056	happens to work on GNU/Linux and some newer BSD systems.
		2057
		2058	The only reasonable use for this function is to call it after forking, if
		2059	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
		2060	the process will result in undefined behaviour. Calling it at any time
		2061	will also result in any undefined (by POSIX) behaviour.
		2062
		2063	=back
1805		2064
1806	=head2 MEMORY USAGE	2065	=head2 MEMORY USAGE
1807		2066
1808	Per-request usage:	2067	Per-request usage:
1809		2068

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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 1.225 by root, Tue Apr 10 05:01:33 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 1.225 by root, Tue Apr 10 05:01:33 2012 UTC