ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/IO-AIO/AIO.pm
(Generate patch)

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.212 by root, Thu Sep 29 22:42:15 2011 UTC vs.
Revision 1.233 by root, Mon Aug 13 01:01:04 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
… …
202 202
203=head1 FUNCTIONS 203=head1 FUNCTIONS
204 204
205=head2 QUICK OVERVIEW 205=head2 QUICK OVERVIEW
206 206
207This section simply lists the prototypes of the most important functions 207This section simply lists the prototypes most of the functions for
208for quick reference. See the following sections for function-by-function 208quick reference. See the following sections for function-by-function
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)
227 aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
225 aio_unlink $pathname, $callback->($status) 228 aio_unlink $pathname, $callback->($status)
226 aio_mknod $pathname, $mode, $dev, $callback->($status) 229 aio_mknod $pathname, $mode, $dev, $callback->($status)
227 aio_link $srcpath, $dstpath, $callback->($status) 230 aio_link $srcpath, $dstpath, $callback->($status)
228 aio_symlink $srcpath, $dstpath, $callback->($status) 231 aio_symlink $srcpath, $dstpath, $callback->($status)
229 aio_readlink $pathname, $callback->($link) 232 aio_readlink $pathname, $callback->($link)
… …
233 aio_rmdir $pathname, $callback->($status) 236 aio_rmdir $pathname, $callback->($status)
234 aio_readdir $pathname, $callback->($entries) 237 aio_readdir $pathname, $callback->($entries)
235 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 238 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST 239 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN 240 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
241 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
238 aio_load $pathname, $data, $callback->($status) 242 aio_load $pathname, $data, $callback->($status)
239 aio_copy $srcpath, $dstpath, $callback->($status) 243 aio_copy $srcpath, $dstpath, $callback->($status)
240 aio_move $srcpath, $dstpath, $callback->($status) 244 aio_move $srcpath, $dstpath, $callback->($status)
241 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242 aio_rmtree $pathname, $callback->($status) 245 aio_rmtree $pathname, $callback->($status)
243 aio_sync $callback->($status) 246 aio_sync $callback->($status)
244 aio_syncfs $fh, $callback->($status) 247 aio_syncfs $fh, $callback->($status)
245 aio_fsync $fh, $callback->($status) 248 aio_fsync $fh, $callback->($status)
246 aio_fdatasync $fh, $callback->($status) 249 aio_fdatasync $fh, $callback->($status)
… …
271 IO::AIO::nready 274 IO::AIO::nready
272 IO::AIO::npending 275 IO::AIO::npending
273 276
274 IO::AIO::sendfile $ofh, $ifh, $offset, $count 277 IO::AIO::sendfile $ofh, $ifh, $offset, $count
275 IO::AIO::fadvise $fh, $offset, $len, $advice 278 IO::AIO::fadvise $fh, $offset, $len, $advice
279 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
280 IO::AIO::munmap $scalar
276 IO::AIO::madvise $scalar, $offset, $length, $advice 281 IO::AIO::madvise $scalar, $offset, $length, $advice
277 IO::AIO::mprotect $scalar, $offset, $length, $protect 282 IO::AIO::mprotect $scalar, $offset, $length, $protect
278 IO::AIO::munlock $scalar, $offset = 0, $length = undef 283 IO::AIO::munlock $scalar, $offset = 0, $length = undef
279 IO::AIO::munlockall 284 IO::AIO::munlockall
280 285
281=head2 AIO REQUEST FUNCTIONS 286=head2 API NOTES
282 287
283All the C<aio_*> calls are more or less thin wrappers around the syscall 288All the C<aio_*> calls are more or less thin wrappers around the syscall
284with the same name (sans C<aio_>). The arguments are similar or identical, 289with the same name (sans C<aio_>). The arguments are similar or identical,
285and they all accept an additional (and optional) C<$callback> argument 290and they all accept an additional (and optional) C<$callback> argument
286which must be a code reference. This code reference will be called after 291which must be a code reference. This code reference will be called after
… …
317correct contents. 322correct contents.
318 323
319This works, btw. independent of the internal UTF-8 bit, which IO::AIO 324This works, btw. independent of the internal UTF-8 bit, which IO::AIO
320handles correctly whether it is set or not. 325handles correctly whether it is set or not.
321 326
327=head2 AIO REQUEST FUNCTIONS
328
322=over 4 329=over 4
323 330
324=item $prev_pri = aioreq_pri [$pri] 331=item $prev_pri = aioreq_pri [$pri]
325 332
326Returns the priority value that would be used for the next request and, if 333Returns the priority value that would be used for the next request and, if
… …
355 362
356 363
357=item aio_open $pathname, $flags, $mode, $callback->($fh) 364=item aio_open $pathname, $flags, $mode, $callback->($fh)
358 365
359Asynchronously open or create a file and call the callback with a newly 366Asynchronously open or create a file and call the callback with a newly
360created filehandle for the file. 367created filehandle for the file (or C<undef> in case of an error).
361 368
362The pathname passed to C<aio_open> must be absolute. See API NOTES, above, 369The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
363for an explanation. 370for an explanation.
364 371
365The C<$flags> argument is a bitmask. See the C<Fcntl> module for a 372The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
… …
407 414
408Or in other words: the file descriptor will be closed, but it will not be 415Or in other words: the file descriptor will be closed, but it will not be
409free for reuse until the perl filehandle is closed. 416free for reuse until the perl filehandle is closed.
410 417
411=cut 418=cut
419
420=item aio_seek $fh, $offset, $whence, $callback->($offs)
421
422Seeks the filehandle to the new C<$offset>, similarly to perl's
423C<sysseek>. The C<$whence> can use the traditional values (C<0> for
424C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
425C<IO::AIO::SEEK_END>).
426
427The resulting absolute offset will be passed to the callback, or C<-1> in
428case of an error.
429
430In theory, the C<$whence> constants could be different than the
431corresponding values from L<Fcntl>, but perl guarantees they are the same,
432so don't panic.
433
434As a GNU/Linux (and maybe Solaris) extension, also the constants
435C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
436could be found. No guarantees about suitability for use in C<aio_seek> or
437Perl's C<sysseek> can be made though, although I would naively assume they
438"just work".
412 439
413=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 440=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
414 441
415=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 442=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
416 443
… …
611 638
612 639
613=item aio_truncate $fh_or_path, $offset, $callback->($status) 640=item aio_truncate $fh_or_path, $offset, $callback->($status)
614 641
615Works like truncate(2) or ftruncate(2). 642Works like truncate(2) or ftruncate(2).
643
644
645=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
646
647Allocates or freed disk space according to the C<$mode> argument. See the
648linux C<fallocate> docuemntation for details.
649
650C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>
651to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE |
652IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.
653
654The file system block size used by C<fallocate> is presumably the
655C<f_bsize> returned by C<statvfs>.
656
657If C<fallocate> isn't available or cannot be emulated (currently no
658emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
616 659
617 660
618=item aio_chmod $fh_or_path, $mode, $callback->($status) 661=item aio_chmod $fh_or_path, $mode, $callback->($status)
619 662
620Works like perl's C<chmod> function. 663Works like perl's C<chmod> function.
… …
1232 1275
1233Example: asynchronously lock all current and future pages into memory. 1276Example: asynchronously lock all current and future pages into memory.
1234 1277
1235 aio_mlockall IO::AIO::MCL_FUTURE; 1278 aio_mlockall IO::AIO::MCL_FUTURE;
1236 1279
1280=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
1281
1282Queries the extents of the given file (by calling the Linux FIEMAP ioctl,
1283see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the
1284C<ioctl> is not available on your OS, then this request will fail with
1285C<ENOSYS>.
1286
1287C<$start> is the starting offset to query extents for, C<$length> is the
1288size of the range to query - if it is C<undef>, then the whole file will
1289be queried.
1290
1291C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
1292C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
1293exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
1294the data portion.
1295
1296C<$count> is the maximum number of extent records to return. If it is
1297C<undef>, then IO::AIO queries all extents of the range. As a very special
1298case, if it is C<0>, then the callback receives the number of extents
1299instead of the extents themselves (which is unreliable, see below).
1300
1301If an error occurs, the callback receives no arguments. The special
1302C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
1303
1304Otherwise, the callback receives an array reference with extent
1305structures. Each extent structure is an array reference itself, with the
1306following members:
1307
1308 [$logical, $physical, $length, $flags]
1309
1310Flags is any combination of the following flag values (typically either C<0>
1311or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
1312
1313C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
1314C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
1315C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1316C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1317C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1318C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1319
1320At the time of this writing (Linux 3.2), this requets is unreliable unless
1321C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
1322it to return all extents of a range for files with large number of
1323extents. The code works around all these issues if C<$count> is undef.
1324
1237=item aio_group $callback->(...) 1325=item aio_group $callback->(...)
1238 1326
1239This is a very special aio request: Instead of doing something, it is a 1327This is a very special aio request: Instead of doing something, it is a
1240container for other aio requests, which is useful if you want to bundle 1328container for other aio requests, which is useful if you want to bundle
1241many requests into a single, composite, request with a definite callback 1329many requests into a single, composite, request with a definite callback
… …
1304object. This object stores the canonicalised, absolute version of the 1392object. This object stores the canonicalised, absolute version of the
1305path, and on systems that allow it, also a directory file descriptor. 1393path, and on systems that allow it, also a directory file descriptor.
1306 1394
1307Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat> 1395Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
1308or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD 1396or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
1309object and a pathname instead. If the pathname is absolute, the 1397object and a pathname instead (or the IO::AIO::WD object alone, which
1398gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
1310IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative 1399IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
1311to that IO::AIO::WD object. 1400to that IO::AIO::WD object.
1312 1401
1313For example, to get a wd object for F</etc> and then stat F<passwd> 1402For example, to get a wd object for F</etc> and then stat F<passwd>
1314inside, you would write: 1403inside, you would write:
1315 1404
… …
1323 aio_stat [$etcdir, "passwd"], sub { 1412 aio_stat [$etcdir, "passwd"], sub {
1324 # yay 1413 # yay
1325 }; 1414 };
1326 }; 1415 };
1327 1416
1328This shows that creating an IO::AIO::WD object is itself a potentially 1417That C<aio_wd> is a request and not a normal function shows that creating
1329blocking operation, which is why it is done asynchronously. 1418an IO::AIO::WD object is itself a potentially blocking operation, which is
1419why it is done asynchronously.
1420
1421To stat the directory obtained with C<aio_wd> above, one could write
1422either of the following three request calls:
1423
1424 aio_lstat "/etc" , sub { ... # pathname as normal string
1425 aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
1426 aio_lstat $wd , sub { ... # shorthand for the previous
1330 1427
1331As with normal pathnames, IO::AIO keeps a copy of the working directory 1428As with normal pathnames, IO::AIO keeps a copy of the working directory
1332object and the pathname string, so you could write the following without 1429object and the pathname string, so you could write the following without
1333causing any issues due to C<$path> getting reused: 1430causing any issues due to C<$path> getting reused:
1334 1431
… …
1834ENOSYS, otherwise the return value of C<mprotect>. 1931ENOSYS, otherwise the return value of C<mprotect>.
1835 1932
1836=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] 1933=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1837 1934
1838Memory-maps a file (or anonymous memory range) and attaches it to the 1935Memory-maps a file (or anonymous memory range) and attaches it to the
1839given C<$scalar>, which will act like a string scalar. 1936given C<$scalar>, which will act like a string scalar. Returns true on
1937success, and false otherwise.
1840 1938
1841The only operations allowed on the scalar are C<substr>/C<vec> that don't 1939The only operations allowed on the scalar are C<substr>/C<vec> that don't
1842change the string length, and most read-only operations such as copying it 1940change the string length, and most read-only operations such as copying it
1843or searching it with regexes and so on. 1941or searching it with regexes and so on.
1844 1942
… …
1897Calls the C<munlockall> function. 1995Calls the C<munlockall> function.
1898 1996
1899On systems that do not implement C<munlockall>, this function returns 1997On systems that do not implement C<munlockall>, this function returns
1900ENOSYS, otherwise the return value of C<munlockall>. 1998ENOSYS, otherwise the return value of C<munlockall>.
1901 1999
2000=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
2001
2002Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
2003C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
2004should be the file offset.
2005
2006C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
2007silently corrupt the data in this case.
2008
2009The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
2010C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
2011C<IO::AIO::SPLICE_F_GIFT>.
2012
2013See the C<splice(2)> manpage for details.
2014
2015=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2016
2017Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
2018description for C<IO::AIO::splice> above for details.
2019
1902=back 2020=back
1903 2021
1904=cut 2022=cut
1905 2023
1906min_parallel 8; 2024min_parallel 8;

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines