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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 1.142 by root, Wed Oct 22 18:15:36 2008 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 $VERSION = '3.16';
199 199
200 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close 200 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
201 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir 201 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir
202 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync 202 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
203 aio_fdatasync aio_pathsync aio_readahead 203 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
204 aio_rename aio_link aio_move aio_copy aio_group 204 aio_rename aio_link aio_move aio_copy aio_group
205 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown 205 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
206 aio_chmod aio_utime aio_truncate); 206 aio_chmod aio_utime aio_truncate);
207 207
208 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); 208 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
224All the C<aio_*> calls are more or less thin wrappers around the syscall 224All the C<aio_*> calls are more or less thin wrappers around the syscall
225with the same name (sans C<aio_>). The arguments are similar or identical, 225with the same name (sans C<aio_>). The arguments are similar or identical,
226and they all accept an additional (and optional) C<$callback> argument 226and they all accept an additional (and optional) C<$callback> argument
227which must be a code reference. This code reference will get called with 227which 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 228the 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 229perl, which usually delivers "false") as its sole argument after the given
230syscall has been executed asynchronously. 230syscall has been executed asynchronously.
231 231
232All functions expecting a filehandle keep a copy of the filehandle 232All functions expecting a filehandle keep a copy of the filehandle
233internally until the request has finished. 233internally until the request has finished.
234 234
248your pathnames to the locale (or other) encoding in effect in the user 248your pathnames to the locale (or other) encoding in effect in the user
249environment, d) use Glib::filename_from_unicode on unicode filenames or e) 249environment, d) use Glib::filename_from_unicode on unicode filenames or e)
250use something else to ensure your scalar has the correct contents. 250use something else to ensure your scalar has the correct contents.
251 251
252This works, btw. independent of the internal UTF-8 bit, which IO::AIO 252This works, btw. independent of the internal UTF-8 bit, which IO::AIO
253handles correctly wether it is set or not. 253handles correctly whether it is set or not.
254 254
255=over 4 255=over 4
256 256
257=item $prev_pri = aioreq_pri [$pri] 257=item $prev_pri = aioreq_pri [$pri]
258 258
565 565
566Try to copy the I<file> (directories not supported as either source or 566Try to copy the I<file> (directories not supported as either source or
567destination) from C<$srcpath> to C<$dstpath> and call the callback with 567destination) from C<$srcpath> to C<$dstpath> and call the callback with
568the C<0> (error) or C<-1> ok. 568the C<0> (error) or C<-1> ok.
569 569
570This is a composite request that it creates the destination file with 570This is a composite request that creates the destination file with
571mode 0200 and copies the contents of the source file into it using 571mode 0200 and copies the contents of the source file into it using
572C<aio_sendfile>, followed by restoring atime, mtime, access mode and 572C<aio_sendfile>, followed by restoring atime, mtime, access mode and
573uid/gid, in that order. 573uid/gid, in that order.
574 574
575If an error occurs, the partial destination file will be unlinked, if 575If an error occurs, the partial destination file will be unlinked, if
631 631
632Try to move the I<file> (directories not supported as either source or 632Try to move the I<file> (directories not supported as either source or
633destination) from C<$srcpath> to C<$dstpath> and call the callback with 633destination) from C<$srcpath> to C<$dstpath> and call the callback with
634the C<0> (error) or C<-1> ok. 634the C<0> (error) or C<-1> ok.
635 635
636This is a composite request that tries to rename(2) the file first. If 636This 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 637rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
638that is successful, unlinking the C<$srcpath>. 638that is successful, unlinks the C<$srcpath>.
639 639
640=cut 640=cut
641 641
642sub aio_move($$;$) { 642sub aio_move($$;$) {
643 my ($src, $dst, $cb) = @_; 643 my ($src, $dst, $cb) = @_;
855callback with the fdatasync result code. 855callback with the fdatasync result code.
856 856
857If this call isn't available because your OS lacks it or it couldn't be 857If 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. 858detected, it will be emulated by calling C<fsync> instead.
859 859
860=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
861
862Sync the data portion of the file specified by C<$offset> and C<$length>
863to disk (but NOT the metadata), by calling the Linux-specific
864sync_file_range call. If sync_file_range is not available or it returns
865ENOSYS, then fdatasync or fsync is being substituted.
866
867C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
868C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
869C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
870manpage for details.
871
860=item aio_pathsync $path, $callback->($status) 872=item aio_pathsync $path, $callback->($status)
861 873
862This request tries to open, fsync and close the given path. This is a 874This request tries to open, fsync and close the given path. This is a
863composite request intended tosync directories after directory operations 875composite request intended to sync directories after directory operations
864(E.g. rename). This might not work on all operating systems or have any 876(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 877specific effect, but usually it makes sure that directory changes get
866written to disc. It works for anything that can be opened for read-only, 878written to disc. It works for anything that can be opened for read-only,
867not just directories. 879not just directories.
868 880
1013Their lifetime, simplified, looks like this: when they are empty, they 1025Their lifetime, simplified, looks like this: when they are empty, they
1014will finish very quickly. If they contain only requests that are in the 1026will finish very quickly. If they contain only requests that are in the
1015C<done> state, they will also finish. Otherwise they will continue to 1027C<done> state, they will also finish. Otherwise they will continue to
1016exist. 1028exist.
1017 1029
1018That means after creating a group you have some time to add requests. And 1030That 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 1031(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 1032the C<poll_cb>). And in the callbacks of those requests, you can add
1021itself finish. 1033further requests to the group. And only when all those requests have
1034finished will the the group itself finish.
1022 1035
1023=over 4 1036=over 4
1024 1037
1025=item add $grp ... 1038=item add $grp ...
1026 1039
1059=item feed $grp $callback->($grp) 1072=item feed $grp $callback->($grp)
1060 1073
1061Sets a feeder/generator on this group: every group can have an attached 1074Sets a feeder/generator on this group: every group can have an attached
1062generator that generates requests if idle. The idea behind this is that, 1075generator 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, 1076although you could just queue as many requests as you want in a group,
1064this might starve other requests for a potentially long time. For 1077this might starve other requests for a potentially long time. For example,
1065example, C<aio_scandir> might generate hundreds of thousands C<aio_stat> 1078C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1066requests, delaying any later requests for a long time. 1079delaying any later requests for a long time.
1067 1080
1068To avoid this, and allow incremental generation of requests, you can 1081To avoid this, and allow incremental generation of requests, you can
1069instead a group and set a feeder on it that generates those requests. The 1082instead 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>, 1083feed 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 1084below) requests active in the group itself and is expected to queue more
1075not impose any limits). 1088not impose any limits).
1076 1089
1077If the feed does not queue more requests when called, it will be 1090If the feed does not queue more requests when called, it will be
1078automatically removed from the group. 1091automatically removed from the group.
1079 1092
1080If the feed limit is C<0>, it will be set to C<2> automatically. 1093If the feed limit is C<0> when this method is called, it will be set to
1094C<2> automatically.
1081 1095
1082Example: 1096Example:
1083 1097
1084 # stat all files in @files, but only ever use four aio requests concurrently: 1098 # stat all files in @files, but only ever use four aio requests concurrently:
1085 1099
1097Sets the feeder limit for the group: The feeder will be called whenever 1111Sets the feeder limit for the group: The feeder will be called whenever
1098the group contains less than this many requests. 1112the group contains less than this many requests.
1099 1113
1100Setting the limit to C<0> will pause the feeding process. 1114Setting the limit to C<0> will pause the feeding process.
1101 1115
1116The default value for the limit is C<0>, but note that setting a feeder
1117automatically bumps it up to C<2>.
1118
1102=back 1119=back
1103 1120
1104=head2 SUPPORT FUNCTIONS 1121=head2 SUPPORT FUNCTIONS
1105 1122
1106=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION 1123=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1117See C<poll_cb> for an example. 1134See C<poll_cb> for an example.
1118 1135
1119=item IO::AIO::poll_cb 1136=item IO::AIO::poll_cb
1120 1137
1121Process some outstanding events on the result pipe. You have to call this 1138Process some outstanding events on the result pipe. You have to call this
1122regularly. Returns the number of events processed. Returns immediately 1139regularly. Returns C<0> if all events could be processed, or C<-1> if it
1140returned earlier for whatever reason. Returns immediately when no events
1123when no events are outstanding. The amount of events processed depends on 1141are 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>. 1142C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
1125 1143
1126If not all requests were processed for whatever reason, the filehandle 1144If not all requests were processed for whatever reason, the filehandle
1127will still be ready when C<poll_cb> returns. 1145will still be ready when C<poll_cb> returns, so normally you don't have to
1146do anything special to have it called later.
1128 1147
1129Example: Install an Event watcher that automatically calls 1148Example: Install an Event watcher that automatically calls
1130IO::AIO::poll_cb with high priority: 1149IO::AIO::poll_cb with high priority:
1131 1150
1132 Event->io (fd => IO::AIO::poll_fileno, 1151 Event->io (fd => IO::AIO::poll_fileno,

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