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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.211 by root, Tue Sep 27 12:10:29 2011 UTC vs.
Revision 1.225 by root, Tue Apr 10 05:01:33 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
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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)
225 aio_unlink $pathname, $callback->($status) 226 aio_unlink $pathname, $callback->($status)
226 aio_mknod $pathname, $mode, $dev, $callback->($status) 227 aio_mknod $pathname, $mode, $dev, $callback->($status)
227 aio_link $srcpath, $dstpath, $callback->($status) 228 aio_link $srcpath, $dstpath, $callback->($status)
228 aio_symlink $srcpath, $dstpath, $callback->($status) 229 aio_symlink $srcpath, $dstpath, $callback->($status)
229 aio_readlink $pathname, $callback->($link) 230 aio_readlink $pathname, $callback->($link)
… …
233 aio_rmdir $pathname, $callback->($status) 234 aio_rmdir $pathname, $callback->($status)
234 aio_readdir $pathname, $callback->($entries) 235 aio_readdir $pathname, $callback->($entries)
235 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 236 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST 237 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237 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)
238 aio_load $pathname, $data, $callback->($status) 240 aio_load $pathname, $data, $callback->($status)
239 aio_copy $srcpath, $dstpath, $callback->($status) 241 aio_copy $srcpath, $dstpath, $callback->($status)
240 aio_move $srcpath, $dstpath, $callback->($status) 242 aio_move $srcpath, $dstpath, $callback->($status)
241 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242 aio_rmtree $pathname, $callback->($status) 243 aio_rmtree $pathname, $callback->($status)
243 aio_sync $callback->($status) 244 aio_sync $callback->($status)
244 aio_syncfs $fh, $callback->($status) 245 aio_syncfs $fh, $callback->($status)
245 aio_fsync $fh, $callback->($status) 246 aio_fsync $fh, $callback->($status)
246 aio_fdatasync $fh, $callback->($status) 247 aio_fdatasync $fh, $callback->($status)
… …
276 IO::AIO::madvise $scalar, $offset, $length, $advice 277 IO::AIO::madvise $scalar, $offset, $length, $advice
277 IO::AIO::mprotect $scalar, $offset, $length, $protect 278 IO::AIO::mprotect $scalar, $offset, $length, $protect
278 IO::AIO::munlock $scalar, $offset = 0, $length = undef 279 IO::AIO::munlock $scalar, $offset = 0, $length = undef
279 IO::AIO::munlockall 280 IO::AIO::munlockall
280 281
281=head2 AIO REQUEST FUNCTIONS 282=head2 API NOTES
282 283
283All the C<aio_*> calls are more or less thin wrappers around the syscall 284All the C<aio_*> calls are more or less thin wrappers around the syscall
284with the same name (sans C<aio_>). The arguments are similar or identical, 285with the same name (sans C<aio_>). The arguments are similar or identical,
285and they all accept an additional (and optional) C<$callback> argument 286and they all accept an additional (and optional) C<$callback> argument
286which must be a code reference. This code reference will get called with 287which must be a code reference. This code reference will be called after
287the syscall return code (e.g. most syscalls return C<-1> on error, unlike 288the syscall has been executed in an asynchronous fashion. The results
288perl, which usually delivers "false") as its sole argument after the given 289of the request will be passed as arguments to the callback (and, if an
289syscall has been executed asynchronously. 290error occured, in C<$!>) - for most requests the syscall return code (e.g.
291most syscalls return C<-1> on error, unlike perl, which usually delivers
292"false").
293
294Some requests (such as C<aio_readdir>) pass the actual results and
295communicate failures by passing C<undef>.
290 296
291All functions expecting a filehandle keep a copy of the filehandle 297All functions expecting a filehandle keep a copy of the filehandle
292internally until the request has finished. 298internally until the request has finished.
293 299
294All functions return request objects of type L<IO::AIO::REQ> that allow 300All functions return request objects of type L<IO::AIO::REQ> that allow
295further manipulation of those requests while they are in-flight. 301further manipulation of those requests while they are in-flight.
296 302
297The pathnames you pass to these routines I<should> be absolute. The 303The 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 304reason for this is that at the time the request is being executed, the
299current working directory could have changed. Alternatively, you can make 305current working directory could have changed. Alternatively, you can
300sure that you never change the current working directory anywhere in 306make sure that you never change the current working directory anywhere
301the program and then use relative paths. Lastly, you can take advantage 307in the program and then use relative paths. You can also take advantage
302of IO::AIOs working directory abstraction - see the description of the 308of IO::AIOs working directory abstraction, that lets you specify paths
309relative to some previously-opened "working directory object" - see the
303C<IO::AIO::WD> class later in this document. 310description of the C<IO::AIO::WD> class later in this document.
304 311
305To encode pathnames as octets, either make sure you either: a) always pass 312To encode pathnames as octets, either make sure you either: a) always pass
306in filenames you got from outside (command line, readdir etc.) without 313in 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 314tinkering, b) are in your native filesystem encoding, c) use the Encode
308your pathnames to the locale (or other) encoding in effect in the user 315module and encode your pathnames to the locale (or other) encoding in
309environment, d) use Glib::filename_from_unicode on unicode filenames or e) 316effect in the user environment, d) use Glib::filename_from_unicode on
310use something else to ensure your scalar has the correct contents. 317unicode filenames or e) use something else to ensure your scalar has the
318correct contents.
311 319
312This works, btw. independent of the internal UTF-8 bit, which IO::AIO 320This works, btw. independent of the internal UTF-8 bit, which IO::AIO
313handles correctly whether it is set or not. 321handles correctly whether it is set or not.
322
323=head2 AIO REQUEST FUNCTIONS
314 324
315=over 4 325=over 4
316 326
317=item $prev_pri = aioreq_pri [$pri] 327=item $prev_pri = aioreq_pri [$pri]
318 328
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400 410
401Or in other words: the file descriptor will be closed, but it will not be 411Or in other words: the file descriptor will be closed, but it will not be
402free for reuse until the perl filehandle is closed. 412free for reuse until the perl filehandle is closed.
403 413
404=cut 414=cut
415
416=item aio_seek $fh, $offset, $whence, $callback->($offs)
417
418Seeks the filehandle to the new C<$offset>, similarly to perl's
419C<sysseek>. The C<$whence> can use the traditional values (C<0> for
420C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
421C<IO::AIO::SEEK_END>).
422
423The resulting absolute offset will be passed to the callback, or C<-1> in
424case of an error.
425
426In theory, the C<$whence> constants could be different than the
427corresponding values from L<Fcntl>, but perl guarantees they are the same,
428so don't panic.
429
430As a GNU/Linux (and maybe Solaris) extension, also the constants
431C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
432could be found. No guarantees about suitability for use in C<aio_seek> or
433Perl's C<sysseek> can be made though, although I would naively assume they
434"just work".
405 435
406=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 436=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
407 437
408=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 438=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
409 439
… …
967 my $grp = aio_group $cb; 997 my $grp = aio_group $cb;
968 998
969 $maxreq = 4 if $maxreq <= 0; 999 $maxreq = 4 if $maxreq <= 0;
970 1000
971 # get a wd object 1001 # get a wd object
972
973 aioreq_pri $pri; 1002 aioreq_pri $pri;
974 add $grp aio_wd $path, sub { 1003 add $grp aio_wd $path, sub {
1004 $_[0]
1005 or return $grp->result ();
1006
975 my $wd = [shift, "."]; 1007 my $wd = [shift, "."];
976 1008
977 # stat once 1009 # stat once
978 aioreq_pri $pri; 1010 aioreq_pri $pri;
979 add $grp aio_stat $wd, sub { 1011 add $grp aio_stat $wd, sub {
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1223 1255
1224Example: asynchronously lock all current and future pages into memory. 1256Example: asynchronously lock all current and future pages into memory.
1225 1257
1226 aio_mlockall IO::AIO::MCL_FUTURE; 1258 aio_mlockall IO::AIO::MCL_FUTURE;
1227 1259
1260=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
1261
1262Queries the extents of the given file (by calling the Linux FIEMAP ioctl,
1263see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the
1264C<ioctl> is not available on your OS, then this rquiest will fail with
1265C<ENOSYS>.
1266
1267C<$start> is the starting offset to query extents for, C<$length> is the
1268size of the range to query - if it is C<undef>, then the whole file will
1269be queried.
1270
1271C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
1272C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
1273exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
1274the data portion.
1275
1276C<$count> is the maximum number of extent records to return. If it is
1277C<undef>, then IO::AIO queries all extents of the file. As a very special
1278case, if it is C<0>, then the callback receives the number of extents
1279instead of the extents themselves.
1280
1281If an error occurs, the callback receives no arguments. The special
1282C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
1283
1284Otherwise, the callback receives an array reference with extent
1285structures. Each extent structure is an array reference itself, with the
1286following members:
1287
1288 [$logical, $physical, $length, $flags]
1289
1290Flags is any combination of the following flag values (typically either C<0>
1291or C<IO::AIO::FIEMAP_EXTENT_LAST>):
1292
1293C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
1294C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
1295C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1296C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1297C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1298C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1299
1228=item aio_group $callback->(...) 1300=item aio_group $callback->(...)
1229 1301
1230This is a very special aio request: Instead of doing something, it is a 1302This is a very special aio request: Instead of doing something, it is a
1231container for other aio requests, which is useful if you want to bundle 1303container for other aio requests, which is useful if you want to bundle
1232many requests into a single, composite, request with a definite callback 1304many requests into a single, composite, request with a definite callback
… …
1295object. This object stores the canonicalised, absolute version of the 1367object. This object stores the canonicalised, absolute version of the
1296path, and on systems that allow it, also a directory file descriptor. 1368path, and on systems that allow it, also a directory file descriptor.
1297 1369
1298Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat> 1370Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
1299or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD 1371or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
1300object and a pathname instead. If the pathname is absolute, the 1372object and a pathname instead (or the IO::AIO::WD object alone, which
1373gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
1301IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative 1374IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
1302to that IO::AIO::WD object. 1375to that IO::AIO::WD object.
1303 1376
1304For example, to get a wd object for F</etc> and then stat F<passwd> 1377For example, to get a wd object for F</etc> and then stat F<passwd>
1305inside, you would write: 1378inside, you would write:
1306 1379
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1314 aio_stat [$etcdir, "passwd"], sub { 1387 aio_stat [$etcdir, "passwd"], sub {
1315 # yay 1388 # yay
1316 }; 1389 };
1317 }; 1390 };
1318 1391
1319This shows that creating an IO::AIO::WD object is itself a potentially 1392That C<aio_wd> is a request and not a normal function shows that creating
1320blocking operation, which is why it is done asynchronously. 1393an IO::AIO::WD object is itself a potentially blocking operation, which is
1394why it is done asynchronously.
1395
1396To stat the directory obtained with C<aio_wd> above, one could write
1397either 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 $wd , sub { ... # shorthand for the previous
1321 1402
1322As with normal pathnames, IO::AIO keeps a copy of the working directory 1403As with normal pathnames, IO::AIO keeps a copy of the working directory
1323object and the pathname string, so you could write the following without 1404object and the pathname string, so you could write the following without
1324causing any issues due to C<$path> getting reused: 1405causing any issues due to C<$path> getting reused:
1325 1406
… …
1888Calls the C<munlockall> function. 1969Calls the C<munlockall> function.
1889 1970
1890On systems that do not implement C<munlockall>, this function returns 1971On systems that do not implement C<munlockall>, this function returns
1891ENOSYS, otherwise the return value of C<munlockall>. 1972ENOSYS, otherwise the return value of C<munlockall>.
1892 1973
1974=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
1975
1976Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
1977C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
1978should be the file offset.
1979
1980The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
1981C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
1982C<IO::AIO::SPLICE_F_GIFT>.
1983
1984See the C<splice(2)> manpage for details.
1985
1986=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
1987
1988Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
1989description for C<IO::AIO::splice> above for details.
1990
1893=back 1991=back
1894 1992
1895=cut 1993=cut
1896 1994
1897min_parallel 8; 1995min_parallel 8;

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