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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.143 by root, Thu Nov 20 09:01:40 2008 UTC vs.
Revision 1.151 by root, Fri Jun 12 00:43:16 2009 UTC

193use strict 'vars'; 193use strict 'vars';
194 194
195use base 'Exporter'; 195use base 'Exporter';
196 196
197BEGIN { 197BEGIN {
198 our $VERSION = '3.17'; 198 our $VERSION = '3.2';
199 199
200 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close 200 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
201 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir 201 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
202 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync 202 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
203 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead 203 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
204 aio_rename aio_link aio_move aio_copy aio_group 204 aio_rename aio_link aio_move aio_copy aio_group
205 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown 205 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
206 aio_chmod aio_utime aio_truncate); 206 aio_chmod aio_utime aio_truncate);
338 338
339=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 339=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
340 340
341=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 341=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
342 342
343Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset> 343Reads or writes C<$length> bytes from or to the specified C<$fh> and
344into the scalar given by C<$data> and offset C<$dataoffset> and calls the 344C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
345callback without the actual number of bytes read (or -1 on error, just 345and calls the callback without the actual number of bytes read (or -1 on
346like the syscall). 346error, just like the syscall).
347
348C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
349offset plus the actual number of bytes read.
347 350
348If C<$offset> is undefined, then the current file descriptor offset will 351If C<$offset> is undefined, then the current file descriptor offset will
349be used (and updated), otherwise the file descriptor offset will not be 352be used (and updated), otherwise the file descriptor offset will not be
350changed by these calls. 353changed by these calls.
351 354
352If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>. 355If C<$length> is undefined in C<aio_write>, use the remaining length of
356C<$data>.
353 357
354If C<$dataoffset> is less than zero, it will be counted from the end of 358If C<$dataoffset> is less than zero, it will be counted from the end of
355C<$data>. 359C<$data>.
356 360
357The C<$data> scalar I<MUST NOT> be modified in any way while the request 361The C<$data> scalar I<MUST NOT> be modified in any way while the request
529 533
530Unlike the POSIX call of the same name, C<aio_readdir> reads an entire 534Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
531directory (i.e. opendir + readdir + closedir). The entries will not be 535directory (i.e. opendir + readdir + closedir). The entries will not be
532sorted, and will B<NOT> include the C<.> and C<..> entries. 536sorted, and will B<NOT> include the C<.> and C<..> entries.
533 537
534The callback a single argument which is either C<undef> or an array-ref 538The callback is passed a single argument which is either C<undef> or an
535with the filenames. 539array-ref with the filenames.
540
541
542=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
543
544Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
545behaviour and output format. In case of an error, C<$entries> will be
546C<undef>.
547
548The flags are a combination of the following constants, ORed together (the
549flags will also be passed to the callback, possibly modified):
550
551=over 4
552
553=item IO::AIO::READDIR_DENTS
554
555When this flag is off, then the callback gets an arrayref with of names
556only (as with C<aio_readdir>), otherwise it gets an arrayref with
557C<[$name, $type, $inode]> arrayrefs, each describing a single directory
558entry in more detail.
559
560C<$name> is the name of the entry.
561
562C<$type> is one of the C<IO::AIO::DT_xxx> constants:
563
564C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
565C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
566C<IO::AIO::DT_WHT>.
567
568C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
569know, you have to run stat yourself. Also, for speed reasons, the C<$type>
570scalars are read-only: you can not modify them.
571
572C<$inode> is the inode number (which might not be exact on systems with 64
573bit inode numbers and 32 bit perls). On systems that do not deliver the
574inode information, this will always be zero.
575
576=item IO::AIO::READDIR_DIRS_FIRST
577
578When this flag is set, then the names will be returned in an order where
579likely directories come first. This is useful when you need to quickly
580find directories, or you want to find all directories while avoiding to
581stat() each entry.
582
583If the system returns type information in readdir, then this is used
584to find directories directly. Otherwise, likely directories are files
585beginning with ".", or otherwise files with no dots, of which files with
586short names are tried first.
587
588=item IO::AIO::READDIR_STAT_ORDER
589
590When this flag is set, then the names will be returned in an order
591suitable for stat()'ing each one. That is, when you plan to stat()
592all files in the given directory, then the returned order will likely
593be fastest.
594
595If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then
596the likely dirs come first, resulting in a less optimal stat order.
597
598=item IO::AIO::READDIR_FOUND_UNKNOWN
599
600This flag should not be set when calling C<aio_readdirx>. Instead, it
601is being set by C<aio_readdirx>, when any of the C<$type>'s found were
602C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
603C<$type>'s are known, which can be used to speed up some algorithms.
604
605=back
536 606
537 607
538=item aio_load $path, $data, $callback->($status) 608=item aio_load $path, $data, $callback->($status)
539 609
540This is a composite request that tries to fully load the given file into 610This is a composite request that tries to fully load the given file into
587 my $grp = aio_group $cb; 657 my $grp = aio_group $cb;
588 658
589 aioreq_pri $pri; 659 aioreq_pri $pri;
590 add $grp aio_open $src, O_RDONLY, 0, sub { 660 add $grp aio_open $src, O_RDONLY, 0, sub {
591 if (my $src_fh = $_[0]) { 661 if (my $src_fh = $_[0]) {
592 my @stat = stat $src_fh; 662 my @stat = stat $src_fh; # hmm, might bock over nfs?
593 663
594 aioreq_pri $pri; 664 aioreq_pri $pri;
595 add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { 665 add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {
596 if (my $dst_fh = $_[0]) { 666 if (my $dst_fh = $_[0]) {
597 aioreq_pri $pri; 667 aioreq_pri $pri;
598 add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { 668 add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
599 if ($_[0] == $stat[7]) { 669 if ($_[0] == $stat[7]) {
600 $grp->result (0); 670 $grp->result (0);
601 close $src_fh; 671 close $src_fh;
602 672
603 # those should not normally block. should. should. 673 my $ch = sub {
604 utime $stat[8], $stat[9], $dst; 674 aioreq_pri $pri;
605 chmod $stat[2] & 07777, $dst_fh; 675 add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
606 chown $stat[4], $stat[5], $dst_fh; 676 aioreq_pri $pri;
677 add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
678 aioreq_pri $pri;
679 add $grp aio_close $dst_fh;
680 }
681 };
682 };
607 683
608 aioreq_pri $pri; 684 aioreq_pri $pri;
609 add $grp aio_close $dst_fh; 685 add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
686 if ($_[0] < 0 && $! == ENOSYS) {
687 aioreq_pri $pri;
688 add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
689 } else {
690 $ch->();
691 }
692 };
610 } else { 693 } else {
611 $grp->result (-1); 694 $grp->result (-1);
612 close $src_fh; 695 close $src_fh;
613 close $dst_fh; 696 close $dst_fh;
614 697
692 775
693Implementation notes. 776Implementation notes.
694 777
695The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can. 778The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
696 779
780If readdir returns file type information, then this is used directly to
781find directories.
782
697After reading the directory, the modification time, size etc. of the 783Otherwise, after reading the directory, the modification time, size etc.
698directory before and after the readdir is checked, and if they match (and 784of the directory before and after the readdir is checked, and if they
699isn't the current time), the link count will be used to decide how many 785match (and isn't the current time), the link count will be used to decide
700entries are directories (if >= 2). Otherwise, no knowledge of the number 786how many entries are directories (if >= 2). Otherwise, no knowledge of the
701of subdirectories will be assumed. 787number of subdirectories will be assumed.
702 788
703Then entries will be sorted into likely directories (everything without 789Then entries will be sorted into likely directories a non-initial dot
704a non-initial dot currently) and likely non-directories (everything 790currently) and likely non-directories (see C<aio_readdirx>). Then every
705else). Then every entry plus an appended C</.> will be C<stat>'ed, 791entry plus an appended C</.> will be C<stat>'ed, likely directories first,
706likely directories first. If that succeeds, it assumes that the entry 792in order of their inode numbers. If that succeeds, it assumes that the
707is a directory or a symlink to directory (which will be checked 793entry is a directory or a symlink to directory (which will be checked
708seperately). This is often faster than stat'ing the entry itself because 794seperately). This is often faster than stat'ing the entry itself because
709filesystems might detect the type of the entry without reading the inode 795filesystems might detect the type of the entry without reading the inode
710data (e.g. ext2fs filetype feature). 796data (e.g. ext2fs filetype feature), even on systems that cannot return
797the filetype information on readdir.
711 798
712If the known number of directories (link count - 2) has been reached, the 799If the known number of directories (link count - 2) has been reached, the
713rest of the entries is assumed to be non-directories. 800rest of the entries is assumed to be non-directories.
714 801
715This only works with certainty on POSIX (= UNIX) filesystems, which 802This only works with certainty on POSIX (= UNIX) filesystems, which
737 my $now = time; 824 my $now = time;
738 my $hash1 = join ":", (stat _)[0,1,3,7,9]; 825 my $hash1 = join ":", (stat _)[0,1,3,7,9];
739 826
740 # read the directory entries 827 # read the directory entries
741 aioreq_pri $pri; 828 aioreq_pri $pri;
742 add $grp aio_readdir $path, sub { 829 add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
743 my $entries = shift 830 my $entries = shift
744 or return $grp->result (); 831 or return $grp->result ();
745 832
746 # stat the dir another time 833 # stat the dir another time
747 aioreq_pri $pri; 834 aioreq_pri $pri;
753 # take the slow route if anything looks fishy 840 # take the slow route if anything looks fishy
754 if ($hash1 ne $hash2 or (stat _)[9] == $now) { 841 if ($hash1 ne $hash2 or (stat _)[9] == $now) {
755 $ndirs = -1; 842 $ndirs = -1;
756 } else { 843 } else {
757 # if nlink == 2, we are finished 844 # if nlink == 2, we are finished
758 # on non-posix-fs's, we rely on nlink < 2 845 # for non-posix-fs's, we rely on nlink < 2
759 $ndirs = (stat _)[3] - 2 846 $ndirs = (stat _)[3] - 2
760 or return $grp->result ([], $entries); 847 or return $grp->result ([], $entries);
761 } 848 }
762 849
763 # sort into likely dirs and likely nondirs
764 # dirs == files without ".", short entries first
765 $entries = [map $_->[0],
766 sort { $b->[1] cmp $a->[1] }
767 map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
768 @$entries];
769
770 my (@dirs, @nondirs); 850 my (@dirs, @nondirs);
771 851
772 my $statgrp = add $grp aio_group sub { 852 my $statgrp = add $grp aio_group sub {
773 $grp->result (\@dirs, \@nondirs); 853 $grp->result (\@dirs, \@nondirs);
774 }; 854 };
775 855
776 limit $statgrp $maxreq; 856 limit $statgrp $maxreq;
777 feed $statgrp sub { 857 feed $statgrp sub {
778 return unless @$entries; 858 return unless @$entries;
779 my $entry = pop @$entries; 859 my $entry = shift @$entries;
780 860
781 aioreq_pri $pri; 861 aioreq_pri $pri;
782 add $statgrp aio_stat "$path/$entry/.", sub { 862 add $statgrp aio_stat "$path/$entry/.", sub {
783 if ($_[0] < 0) { 863 if ($_[0] < 0) {
784 push @nondirs, $entry; 864 push @nondirs, $entry;
965=item cancel $req 1045=item cancel $req
966 1046
967Cancels the request, if possible. Has the effect of skipping execution 1047Cancels the request, if possible. Has the effect of skipping execution
968when entering the B<execute> state and skipping calling the callback when 1048when entering the B<execute> state and skipping calling the callback when
969entering the the B<result> state, but will leave the request otherwise 1049entering the the B<result> state, but will leave the request otherwise
970untouched. That means that requests that currently execute will not be 1050untouched (with the exception of readdir). That means that requests that
971stopped and resources held by the request will not be freed prematurely. 1051currently execute will not be stopped and resources held by the request
1052will not be freed prematurely.
972 1053
973=item cb $req $callback->(...) 1054=item cb $req $callback->(...)
974 1055
975Replace (or simply set) the callback registered to the request. 1056Replace (or simply set) the callback registered to the request.
976 1057

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