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Revision 1.210 by root, Tue Sep 27 01:43:03 2011 UTC vs.
Revision 1.229 by root, Wed Jul 25 16:32:30 2012 UTC

… …
168use common::sense; 168use common::sense;
169 169
170use base 'Exporter'; 170use base 'Exporter';
171 171
172BEGIN { 172BEGIN {
173 our $VERSION = '4.0'; 173 our $VERSION = '4.15';
174 174
175 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close 175 our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
176 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx 176 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync 177 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
178 aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate 178 aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate
179 aio_pathsync aio_readahead 179 aio_pathsync aio_readahead aio_fiemap
180 aio_rename aio_link aio_move aio_copy aio_group 180 aio_rename aio_link aio_move aio_copy aio_group
181 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown 181 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182 aio_chmod aio_utime aio_truncate 182 aio_chmod aio_utime aio_truncate
183 aio_msync aio_mtouch aio_mlock aio_mlockall 183 aio_msync aio_mtouch aio_mlock aio_mlockall
184 aio_statvfs 184 aio_statvfs
… …
209documentation. 209documentation.
210 210
211 aio_wd $pathname, $callback->($wd) 211 aio_wd $pathname, $callback->($wd)
212 aio_open $pathname, $flags, $mode, $callback->($fh) 212 aio_open $pathname, $flags, $mode, $callback->($fh)
213 aio_close $fh, $callback->($status) 213 aio_close $fh, $callback->($status)
214 aio_seek $fh,$offset,$whence, $callback->($offs)
214 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 215 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
215 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 216 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
216 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) 217 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
217 aio_readahead $fh,$offset,$length, $callback->($retval) 218 aio_readahead $fh,$offset,$length, $callback->($retval)
218 aio_stat $fh_or_path, $callback->($status) 219 aio_stat $fh_or_path, $callback->($status)
219 aio_lstat $fh, $callback->($status) 220 aio_lstat $fh, $callback->($status)
220 aio_statvfs $fh_or_path, $callback->($statvfs) 221 aio_statvfs $fh_or_path, $callback->($statvfs)
221 aio_utime $fh_or_path, $atime, $mtime, $callback->($status) 222 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
222 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)
223 aio_truncate $fh_or_path, $offset, $callback->($status) 225 aio_truncate $fh_or_path, $offset, $callback->($status)
224 aio_chmod $fh_or_path, $mode, $callback->($status) 226 aio_allocate $fh, $mode, $offset, $len, $callback->($status)
225 aio_unlink $pathname, $callback->($status) 227 aio_unlink $pathname, $callback->($status)
226 aio_mknod $pathname, $mode, $dev, $callback->($status) 228 aio_mknod $pathname, $mode, $dev, $callback->($status)
227 aio_link $srcpath, $dstpath, $callback->($status) 229 aio_link $srcpath, $dstpath, $callback->($status)
228 aio_symlink $srcpath, $dstpath, $callback->($status) 230 aio_symlink $srcpath, $dstpath, $callback->($status)
229 aio_readlink $pathname, $callback->($link) 231 aio_readlink $pathname, $callback->($link)
… …
233 aio_rmdir $pathname, $callback->($status) 235 aio_rmdir $pathname, $callback->($status)
234 aio_readdir $pathname, $callback->($entries) 236 aio_readdir $pathname, $callback->($entries)
235 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 237 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST 238 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN 239 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
240 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
238 aio_load $pathname, $data, $callback->($status) 241 aio_load $pathname, $data, $callback->($status)
239 aio_copy $srcpath, $dstpath, $callback->($status) 242 aio_copy $srcpath, $dstpath, $callback->($status)
240 aio_move $srcpath, $dstpath, $callback->($status) 243 aio_move $srcpath, $dstpath, $callback->($status)
241 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242 aio_rmtree $pathname, $callback->($status) 244 aio_rmtree $pathname, $callback->($status)
243 aio_sync $callback->($status) 245 aio_sync $callback->($status)
244 aio_syncfs $fh, $callback->($status) 246 aio_syncfs $fh, $callback->($status)
245 aio_fsync $fh, $callback->($status) 247 aio_fsync $fh, $callback->($status)
246 aio_fdatasync $fh, $callback->($status) 248 aio_fdatasync $fh, $callback->($status)
… …
271 IO::AIO::nready 273 IO::AIO::nready
272 IO::AIO::npending 274 IO::AIO::npending
273 275
274 IO::AIO::sendfile $ofh, $ifh, $offset, $count 276 IO::AIO::sendfile $ofh, $ifh, $offset, $count
275 IO::AIO::fadvise $fh, $offset, $len, $advice 277 IO::AIO::fadvise $fh, $offset, $len, $advice
278 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
279 IO::AIO::munmap $scalar
276 IO::AIO::madvise $scalar, $offset, $length, $advice 280 IO::AIO::madvise $scalar, $offset, $length, $advice
277 IO::AIO::mprotect $scalar, $offset, $length, $protect 281 IO::AIO::mprotect $scalar, $offset, $length, $protect
278 IO::AIO::munlock $scalar, $offset = 0, $length = undef 282 IO::AIO::munlock $scalar, $offset = 0, $length = undef
279 IO::AIO::munlockall 283 IO::AIO::munlockall
280 284
281=head2 AIO REQUEST FUNCTIONS 285=head2 API NOTES
282 286
283All the C<aio_*> calls are more or less thin wrappers around the syscall 287All the C<aio_*> calls are more or less thin wrappers around the syscall
284with the same name (sans C<aio_>). The arguments are similar or identical, 288with the same name (sans C<aio_>). The arguments are similar or identical,
285and they all accept an additional (and optional) C<$callback> argument 289and they all accept an additional (and optional) C<$callback> argument
286which must be a code reference. This code reference will get called with 290which must be a code reference. This code reference will be called after
287the syscall return code (e.g. most syscalls return C<-1> on error, unlike 291the syscall has been executed in an asynchronous fashion. The results
288perl, which usually delivers "false") as its sole argument after the given 292of the request will be passed as arguments to the callback (and, if an
289syscall has been executed asynchronously. 293error occured, in C<$!>) - for most requests the syscall return code (e.g.
294most syscalls return C<-1> on error, unlike perl, which usually delivers
295"false").
296
297Some requests (such as C<aio_readdir>) pass the actual results and
298communicate failures by passing C<undef>.
290 299
291All functions expecting a filehandle keep a copy of the filehandle 300All functions expecting a filehandle keep a copy of the filehandle
292internally until the request has finished. 301internally until the request has finished.
293 302
294All functions return request objects of type L<IO::AIO::REQ> that allow 303All functions return request objects of type L<IO::AIO::REQ> that allow
295further manipulation of those requests while they are in-flight. 304further manipulation of those requests while they are in-flight.
296 305
297The pathnames you pass to these routines I<should> be absolute. The 306The pathnames you pass to these routines I<should> be absolute. The
298reason for this is that at the time the request is being executed, the 307reason for this is that at the time the request is being executed, the
299current working directory could have changed. Alternatively, you can make 308current working directory could have changed. Alternatively, you can
300sure that you never change the current working directory anywhere in 309make sure that you never change the current working directory anywhere
301the program and then use relative paths. Lastly, you can take advantage 310in the program and then use relative paths. You can also take advantage
302of IO::AIOs working directory abstraction - see the description of the 311of IO::AIOs working directory abstraction, that lets you specify paths
312relative to some previously-opened "working directory object" - see the
303C<IO::AIO::WD> class later in this document. 313description of the C<IO::AIO::WD> class later in this document.
304 314
305To encode pathnames as octets, either make sure you either: a) always pass 315To encode pathnames as octets, either make sure you either: a) always pass
306in filenames you got from outside (command line, readdir etc.) without 316in filenames you got from outside (command line, readdir etc.) without
307tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode 317tinkering, b) are in your native filesystem encoding, c) use the Encode
308your pathnames to the locale (or other) encoding in effect in the user 318module and encode your pathnames to the locale (or other) encoding in
309environment, d) use Glib::filename_from_unicode on unicode filenames or e) 319effect in the user environment, d) use Glib::filename_from_unicode on
310use something else to ensure your scalar has the correct contents. 320unicode filenames or e) use something else to ensure your scalar has the
321correct contents.
311 322
312This works, btw. independent of the internal UTF-8 bit, which IO::AIO 323This works, btw. independent of the internal UTF-8 bit, which IO::AIO
313handles correctly whether it is set or not. 324handles correctly whether it is set or not.
325
326=head2 AIO REQUEST FUNCTIONS
314 327
315=over 4 328=over 4
316 329
317=item $prev_pri = aioreq_pri [$pri] 330=item $prev_pri = aioreq_pri [$pri]
318 331
… …
400 413
401Or in other words: the file descriptor will be closed, but it will not be 414Or in other words: the file descriptor will be closed, but it will not be
402free for reuse until the perl filehandle is closed. 415free for reuse until the perl filehandle is closed.
403 416
404=cut 417=cut
418
419=item aio_seek $fh, $offset, $whence, $callback->($offs)
420
421Seeks the filehandle to the new C<$offset>, similarly to perl's
422C<sysseek>. The C<$whence> can use the traditional values (C<0> for
423C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
424C<IO::AIO::SEEK_END>).
425
426The resulting absolute offset will be passed to the callback, or C<-1> in
427case of an error.
428
429In theory, the C<$whence> constants could be different than the
430corresponding values from L<Fcntl>, but perl guarantees they are the same,
431so don't panic.
432
433As a GNU/Linux (and maybe Solaris) extension, also the constants
434C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
435could be found. No guarantees about suitability for use in C<aio_seek> or
436Perl's C<sysseek> can be made though, although I would naively assume they
437"just work".
405 438
406=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 439=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
407 440
408=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 441=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
409 442
… …
606=item aio_truncate $fh_or_path, $offset, $callback->($status) 639=item aio_truncate $fh_or_path, $offset, $callback->($status)
607 640
608Works like truncate(2) or ftruncate(2). 641Works like truncate(2) or ftruncate(2).
609 642
610 643
644=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
645
646Allocates or freed disk space according to the C<$mode> argument. See the
647linux C<fallocate> docuemntation for details.
648
649C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>
650to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE |
651IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.
652
653The file system block size used by C<fallocate> is presumably the
654C<f_bsize> returned by C<statvfs>.
655
656If C<fallocate> isn't available or cannot be emulated (currently no
657emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
658
659
611=item aio_chmod $fh_or_path, $mode, $callback->($status) 660=item aio_chmod $fh_or_path, $mode, $callback->($status)
612 661
613Works like perl's C<chmod> function. 662Works like perl's C<chmod> function.
614 663
615 664
… …
967 my $grp = aio_group $cb; 1016 my $grp = aio_group $cb;
968 1017
969 $maxreq = 4 if $maxreq <= 0; 1018 $maxreq = 4 if $maxreq <= 0;
970 1019
971 # get a wd object 1020 # get a wd object
972
973 aioreq_pri $pri; 1021 aioreq_pri $pri;
974 add $grp aio_wd $path, sub { 1022 add $grp aio_wd $path, sub {
1023 $_[0]
1024 or return $grp->result ();
1025
975 my $wd = [shift, "."]; 1026 my $wd = [shift, "."];
976 1027
977 # stat once 1028 # stat once
978 aioreq_pri $pri; 1029 aioreq_pri $pri;
979 add $grp aio_stat $wd, sub { 1030 add $grp aio_stat $wd, sub {
… …
1223 1274
1224Example: asynchronously lock all current and future pages into memory. 1275Example: asynchronously lock all current and future pages into memory.
1225 1276
1226 aio_mlockall IO::AIO::MCL_FUTURE; 1277 aio_mlockall IO::AIO::MCL_FUTURE;
1227 1278
1279=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
1280
1281Queries the extents of the given file (by calling the Linux FIEMAP ioctl,
1282see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the
1283C<ioctl> is not available on your OS, then this rquiest will fail with
1284C<ENOSYS>.
1285
1286C<$start> is the starting offset to query extents for, C<$length> is the
1287size of the range to query - if it is C<undef>, then the whole file will
1288be queried.
1289
1290C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
1291C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
1292exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
1293the data portion.
1294
1295C<$count> is the maximum number of extent records to return. If it is
1296C<undef>, then IO::AIO queries all extents of the file. As a very special
1297case, if it is C<0>, then the callback receives the number of extents
1298instead of the extents themselves.
1299
1300If an error occurs, the callback receives no arguments. The special
1301C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
1302
1303Otherwise, the callback receives an array reference with extent
1304structures. Each extent structure is an array reference itself, with the
1305following members:
1306
1307 [$logical, $physical, $length, $flags]
1308
1309Flags is any combination of the following flag values (typically either C<0>
1310or C<IO::AIO::FIEMAP_EXTENT_LAST>):
1311
1312C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
1313C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
1314C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1315C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1316C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1317C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1318
1228=item aio_group $callback->(...) 1319=item aio_group $callback->(...)
1229 1320
1230This is a very special aio request: Instead of doing something, it is a 1321This is a very special aio request: Instead of doing something, it is a
1231container for other aio requests, which is useful if you want to bundle 1322container for other aio requests, which is useful if you want to bundle
1232many requests into a single, composite, request with a definite callback 1323many requests into a single, composite, request with a definite callback
… …
1295object. This object stores the canonicalised, absolute version of the 1386object. This object stores the canonicalised, absolute version of the
1296path, and on systems that allow it, also a directory file descriptor. 1387path, and on systems that allow it, also a directory file descriptor.
1297 1388
1298Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat> 1389Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
1299or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD 1390or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
1300object and a pathname instead. If the pathname is absolute, the 1391object and a pathname instead (or the IO::AIO::WD object alone, which
1392gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
1301IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative 1393IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
1302to that IO::AIO::WD object. 1394to that IO::AIO::WD object.
1303 1395
1304For example, to get a wd object for F</etc> and then stat F<passwd> 1396For example, to get a wd object for F</etc> and then stat F<passwd>
1305inside, you would write: 1397inside, you would write:
1306 1398
… …
1314 aio_stat [$etcdir, "passwd"], sub { 1406 aio_stat [$etcdir, "passwd"], sub {
1315 # yay 1407 # yay
1316 }; 1408 };
1317 }; 1409 };
1318 1410
1319This shows that creating an IO::AIO::WD object is itself a potentially 1411That C<aio_wd> is a request and not a normal function shows that creating
1320blocking operation, which is why it is done asynchronously. 1412an IO::AIO::WD object is itself a potentially blocking operation, which is
1413why it is done asynchronously.
1414
1415To stat the directory obtained with C<aio_wd> above, one could write
1416either of the following three request calls:
1417
1418 aio_lstat "/etc" , sub { ... # pathname as normal string
1419 aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
1420 aio_lstat $wd , sub { ... # shorthand for the previous
1321 1421
1322As with normal pathnames, IO::AIO keeps a copy of the working directory 1422As with normal pathnames, IO::AIO keeps a copy of the working directory
1323object and the pathname string, so you could write the following without 1423object and the pathname string, so you could write the following without
1324causing any issues due to C<$path> getting reused: 1424causing any issues due to C<$path> getting reused:
1325 1425
… …
1505 1605
1506Sets a feeder/generator on this group: every group can have an attached 1606Sets a feeder/generator on this group: every group can have an attached
1507generator that generates requests if idle. The idea behind this is that, 1607generator that generates requests if idle. The idea behind this is that,
1508although you could just queue as many requests as you want in a group, 1608although you could just queue as many requests as you want in a group,
1509this might starve other requests for a potentially long time. For example, 1609this might starve other requests for a potentially long time. For example,
1510C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests, 1610C<aio_scandir> might generate hundreds of thousands of C<aio_stat>
1511delaying any later requests for a long time. 1611requests, delaying any later requests for a long time.
1512 1612
1513To avoid this, and allow incremental generation of requests, you can 1613To avoid this, and allow incremental generation of requests, you can
1514instead a group and set a feeder on it that generates those requests. The 1614instead a group and set a feeder on it that generates those requests. The
1515feed callback will be called whenever there are few enough (see C<limit>, 1615feed callback will be called whenever there are few enough (see C<limit>,
1516below) requests active in the group itself and is expected to queue more 1616below) requests active in the group itself and is expected to queue more
… …
1825ENOSYS, otherwise the return value of C<mprotect>. 1925ENOSYS, otherwise the return value of C<mprotect>.
1826 1926
1827=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] 1927=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1828 1928
1829Memory-maps a file (or anonymous memory range) and attaches it to the 1929Memory-maps a file (or anonymous memory range) and attaches it to the
1830given C<$scalar>, which will act like a string scalar. 1930given C<$scalar>, which will act like a string scalar. Returns true on
1931success, and false otherwise.
1831 1932
1832The only operations allowed on the scalar are C<substr>/C<vec> that don't 1933The only operations allowed on the scalar are C<substr>/C<vec> that don't
1833change the string length, and most read-only operations such as copying it 1934change the string length, and most read-only operations such as copying it
1834or searching it with regexes and so on. 1935or searching it with regexes and so on.
1835 1936
… …
1888Calls the C<munlockall> function. 1989Calls the C<munlockall> function.
1889 1990
1890On systems that do not implement C<munlockall>, this function returns 1991On systems that do not implement C<munlockall>, this function returns
1891ENOSYS, otherwise the return value of C<munlockall>. 1992ENOSYS, otherwise the return value of C<munlockall>.
1892 1993
1994=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
1995
1996Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
1997C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
1998should be the file offset.
1999
2000C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
2001silently corrupt the data in this case.
2002
2003The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
2004C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
2005C<IO::AIO::SPLICE_F_GIFT>.
2006
2007See the C<splice(2)> manpage for details.
2008
2009=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2010
2011Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
2012description for C<IO::AIO::splice> above for details.
2013
1893=back 2014=back
1894 2015
1895=cut 2016=cut
1896 2017
1897min_parallel 8; 2018min_parallel 8;

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