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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.125 by root, Sat May 10 22:47:34 2008 UTC vs.
Revision 1.145 by root, Sun Apr 19 19:20:10 2009 UTC

193use strict 'vars'; 193use strict 'vars';
194 194
195use base 'Exporter'; 195use base 'Exporter';
196 196
197BEGIN { 197BEGIN {
198 our $VERSION = '3.0'; 198 our $VERSION = '3.18';
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
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_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);
207 207
208 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); 208 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
209 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush 209 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
210 min_parallel max_parallel max_idle 210 min_parallel max_parallel max_idle
211 nreqs nready npending nthreads 211 nreqs nready npending nthreads
212 max_poll_time max_poll_reqs); 212 max_poll_time max_poll_reqs);
213 213
214 push @AIO_REQ, qw(aio_busy); # not exported
215
214 @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; 216 @IO::AIO::GRP::ISA = 'IO::AIO::REQ';
215 217
216 require XSLoader; 218 require XSLoader;
217 XSLoader::load ("IO::AIO", $VERSION); 219 XSLoader::load ("IO::AIO", $VERSION);
218} 220}
224All the C<aio_*> calls are more or less thin wrappers around the syscall 226All the C<aio_*> calls are more or less thin wrappers around the syscall
225with the same name (sans C<aio_>). The arguments are similar or identical, 227with the same name (sans C<aio_>). The arguments are similar or identical,
226and they all accept an additional (and optional) C<$callback> argument 228and they all accept an additional (and optional) C<$callback> argument
227which must be a code reference. This code reference will get called with 229which must be a code reference. This code reference will get called with
228the syscall return code (e.g. most syscalls return C<-1> on error, unlike 230the syscall return code (e.g. most syscalls return C<-1> on error, unlike
229perl, which usually delivers "false") as it's sole argument when the given 231perl, which usually delivers "false") as its sole argument after the given
230syscall has been executed asynchronously. 232syscall has been executed asynchronously.
231 233
232All functions expecting a filehandle keep a copy of the filehandle 234All functions expecting a filehandle keep a copy of the filehandle
233internally until the request has finished. 235internally until the request has finished.
234 236
248your pathnames to the locale (or other) encoding in effect in the user 250your pathnames to the locale (or other) encoding in effect in the user
249environment, d) use Glib::filename_from_unicode on unicode filenames or e) 251environment, d) use Glib::filename_from_unicode on unicode filenames or e)
250use something else to ensure your scalar has the correct contents. 252use something else to ensure your scalar has the correct contents.
251 253
252This works, btw. independent of the internal UTF-8 bit, which IO::AIO 254This works, btw. independent of the internal UTF-8 bit, which IO::AIO
253handles correctly wether it is set or not. 255handles correctly whether it is set or not.
254 256
255=over 4 257=over 4
256 258
257=item $prev_pri = aioreq_pri [$pri] 259=item $prev_pri = aioreq_pri [$pri]
258 260
336 338
337=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 339=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
338 340
339=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 341=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
340 342
341Reads 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<$fh> and
342into the scalar given by C<$data> and offset C<$dataoffset> and calls the 344C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
343callback 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
344like the syscall). 346error, just like the syscall).
345 347
346If C<$offset> is undefined, then the current file descriptor offset will 348If C<$offset> is undefined, then the current file descriptor offset will
347be used (and updated), otherwise the file descriptor offset will not be 349be used (and updated), otherwise the file descriptor offset will not be
348changed by these calls. 350changed by these calls.
349 351
350If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>. 352If C<$length> is undefined in C<aio_write>, use the remaining length of
353C<$data>.
351 354
352If C<$dataoffset> is less than zero, it will be counted from the end of 355If C<$dataoffset> is less than zero, it will be counted from the end of
353C<$data>. 356C<$data>.
354 357
355The C<$data> scalar I<MUST NOT> be modified in any way while the request 358The C<$data> scalar I<MUST NOT> be modified in any way while the request
565 568
566Try to copy the I<file> (directories not supported as either source or 569Try to copy the I<file> (directories not supported as either source or
567destination) from C<$srcpath> to C<$dstpath> and call the callback with 570destination) from C<$srcpath> to C<$dstpath> and call the callback with
568the C<0> (error) or C<-1> ok. 571the C<0> (error) or C<-1> ok.
569 572
570This is a composite request that it creates the destination file with 573This is a composite request that creates the destination file with
571mode 0200 and copies the contents of the source file into it using 574mode 0200 and copies the contents of the source file into it using
572C<aio_sendfile>, followed by restoring atime, mtime, access mode and 575C<aio_sendfile>, followed by restoring atime, mtime, access mode and
573uid/gid, in that order. 576uid/gid, in that order.
574 577
575If an error occurs, the partial destination file will be unlinked, if 578If an error occurs, the partial destination file will be unlinked, if
631 634
632Try to move the I<file> (directories not supported as either source or 635Try to move the I<file> (directories not supported as either source or
633destination) from C<$srcpath> to C<$dstpath> and call the callback with 636destination) from C<$srcpath> to C<$dstpath> and call the callback with
634the C<0> (error) or C<-1> ok. 637the C<0> (error) or C<-1> ok.
635 638
636This is a composite request that tries to rename(2) the file first. If 639This is a composite request that tries to rename(2) the file first; if
637rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if 640rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
638that is successful, unlinking the C<$srcpath>. 641that is successful, unlinks the C<$srcpath>.
639 642
640=cut 643=cut
641 644
642sub aio_move($$;$) { 645sub aio_move($$;$) {
643 my ($src, $dst, $cb) = @_; 646 my ($src, $dst, $cb) = @_;
855callback with the fdatasync result code. 858callback with the fdatasync result code.
856 859
857If this call isn't available because your OS lacks it or it couldn't be 860If this call isn't available because your OS lacks it or it couldn't be
858detected, it will be emulated by calling C<fsync> instead. 861detected, it will be emulated by calling C<fsync> instead.
859 862
863=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
864
865Sync the data portion of the file specified by C<$offset> and C<$length>
866to disk (but NOT the metadata), by calling the Linux-specific
867sync_file_range call. If sync_file_range is not available or it returns
868ENOSYS, then fdatasync or fsync is being substituted.
869
870C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
871C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
872C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
873manpage for details.
874
860=item aio_pathsync $path, $callback->($status) 875=item aio_pathsync $path, $callback->($status)
861 876
862This request tries to open, fsync and close the given path. This is a 877This request tries to open, fsync and close the given path. This is a
863composite request intended tosync directories after directory operations 878composite request intended to sync directories after directory operations
864(E.g. rename). This might not work on all operating systems or have any 879(E.g. rename). This might not work on all operating systems or have any
865specific effect, but usually it makes sure that directory changes get 880specific effect, but usually it makes sure that directory changes get
866written to disc. It works for anything that can be opened for read-only, 881written to disc. It works for anything that can be opened for read-only,
867not just directories. 882not just directories.
868 883
1013Their lifetime, simplified, looks like this: when they are empty, they 1028Their lifetime, simplified, looks like this: when they are empty, they
1014will finish very quickly. If they contain only requests that are in the 1029will finish very quickly. If they contain only requests that are in the
1015C<done> state, they will also finish. Otherwise they will continue to 1030C<done> state, they will also finish. Otherwise they will continue to
1016exist. 1031exist.
1017 1032
1018That means after creating a group you have some time to add requests. And 1033That means after creating a group you have some time to add requests
1019in the callbacks of those requests, you can add further requests to the 1034(precisely before the callback has been invoked, which is only done within
1020group. And only when all those requests have finished will the the group 1035the C<poll_cb>). And in the callbacks of those requests, you can add
1021itself finish. 1036further requests to the group. And only when all those requests have
1037finished will the the group itself finish.
1022 1038
1023=over 4 1039=over 4
1024 1040
1025=item add $grp ... 1041=item add $grp ...
1026 1042
1059=item feed $grp $callback->($grp) 1075=item feed $grp $callback->($grp)
1060 1076
1061Sets a feeder/generator on this group: every group can have an attached 1077Sets a feeder/generator on this group: every group can have an attached
1062generator that generates requests if idle. The idea behind this is that, 1078generator that generates requests if idle. The idea behind this is that,
1063although you could just queue as many requests as you want in a group, 1079although you could just queue as many requests as you want in a group,
1064this might starve other requests for a potentially long time. For 1080this might starve other requests for a potentially long time. For example,
1065example, C<aio_scandir> might generate hundreds of thousands C<aio_stat> 1081C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1066requests, delaying any later requests for a long time. 1082delaying any later requests for a long time.
1067 1083
1068To avoid this, and allow incremental generation of requests, you can 1084To avoid this, and allow incremental generation of requests, you can
1069instead a group and set a feeder on it that generates those requests. The 1085instead a group and set a feeder on it that generates those requests. The
1070feed callback will be called whenever there are few enough (see C<limit>, 1086feed callback will be called whenever there are few enough (see C<limit>,
1071below) requests active in the group itself and is expected to queue more 1087below) requests active in the group itself and is expected to queue more
1075not impose any limits). 1091not impose any limits).
1076 1092
1077If the feed does not queue more requests when called, it will be 1093If the feed does not queue more requests when called, it will be
1078automatically removed from the group. 1094automatically removed from the group.
1079 1095
1080If the feed limit is C<0>, it will be set to C<2> automatically. 1096If the feed limit is C<0> when this method is called, it will be set to
1097C<2> automatically.
1081 1098
1082Example: 1099Example:
1083 1100
1084 # stat all files in @files, but only ever use four aio requests concurrently: 1101 # stat all files in @files, but only ever use four aio requests concurrently:
1085 1102
1097Sets the feeder limit for the group: The feeder will be called whenever 1114Sets the feeder limit for the group: The feeder will be called whenever
1098the group contains less than this many requests. 1115the group contains less than this many requests.
1099 1116
1100Setting the limit to C<0> will pause the feeding process. 1117Setting the limit to C<0> will pause the feeding process.
1101 1118
1119The default value for the limit is C<0>, but note that setting a feeder
1120automatically bumps it up to C<2>.
1121
1102=back 1122=back
1103 1123
1104=head2 SUPPORT FUNCTIONS 1124=head2 SUPPORT FUNCTIONS
1105 1125
1106=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION 1126=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1117See C<poll_cb> for an example. 1137See C<poll_cb> for an example.
1118 1138
1119=item IO::AIO::poll_cb 1139=item IO::AIO::poll_cb
1120 1140
1121Process some outstanding events on the result pipe. You have to call this 1141Process some outstanding events on the result pipe. You have to call this
1122regularly. Returns the number of events processed. Returns immediately 1142regularly. Returns C<0> if all events could be processed, or C<-1> if it
1143returned earlier for whatever reason. Returns immediately when no events
1123when no events are outstanding. The amount of events processed depends on 1144are outstanding. The amount of events processed depends on the settings of
1124the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. 1145C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
1125 1146
1126If not all requests were processed for whatever reason, the filehandle 1147If not all requests were processed for whatever reason, the filehandle
1127will still be ready when C<poll_cb> returns. 1148will still be ready when C<poll_cb> returns, so normally you don't have to
1149do anything special to have it called later.
1128 1150
1129Example: Install an Event watcher that automatically calls 1151Example: Install an Event watcher that automatically calls
1130IO::AIO::poll_cb with high priority: 1152IO::AIO::poll_cb with high priority:
1131 1153
1132 Event->io (fd => IO::AIO::poll_fileno, 1154 Event->io (fd => IO::AIO::poll_fileno,

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