1 | =head1 NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | IO::AIO - Asynchronous Input/Output |
3 | IO::AIO - Asynchronous/Advanced Input/Output |
4 | |
4 | |
5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
6 | |
6 | |
7 | use IO::AIO; |
7 | use IO::AIO; |
8 | |
8 | |
9 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
9 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
10 | my ($fh) = @_; |
10 | my $fh = shift |
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11 | or die "/etc/passwd: $!"; |
11 | ... |
12 | ... |
12 | }; |
13 | }; |
13 | |
14 | |
14 | aio_unlink "/tmp/file", sub { }; |
15 | aio_unlink "/tmp/file", sub { }; |
15 | |
16 | |
… | |
… | |
25 | $req->cancel; # cancel request if still in queue |
26 | $req->cancel; # cancel request if still in queue |
26 | |
27 | |
27 | my $grp = aio_group sub { print "all stats done\n" }; |
28 | my $grp = aio_group sub { print "all stats done\n" }; |
28 | add $grp aio_stat "..." for ...; |
29 | add $grp aio_stat "..." for ...; |
29 | |
30 | |
30 | # AnyEvent integration |
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31 | open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; |
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32 | my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
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33 | |
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34 | # Event integration |
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35 | Event->io (fd => IO::AIO::poll_fileno, |
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36 | poll => 'r', |
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37 | cb => \&IO::AIO::poll_cb); |
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38 | |
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39 | # Glib/Gtk2 integration |
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40 | add_watch Glib::IO IO::AIO::poll_fileno, |
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41 | in => sub { IO::AIO::poll_cb; 1 }; |
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42 | |
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43 | # Tk integration |
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44 | Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "", |
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45 | readable => \&IO::AIO::poll_cb); |
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46 | |
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47 | # Danga::Socket integration |
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48 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
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49 | \&IO::AIO::poll_cb); |
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50 | |
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51 | =head1 DESCRIPTION |
31 | =head1 DESCRIPTION |
52 | |
32 | |
53 | This module implements asynchronous I/O using whatever means your |
33 | This module implements asynchronous I/O using whatever means your |
54 | operating system supports. |
34 | operating system supports. It is implemented as an interface to C<libeio> |
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35 | (L<http://software.schmorp.de/pkg/libeio.html>). |
55 | |
36 | |
56 | Asynchronous means that operations that can normally block your program |
37 | Asynchronous means that operations that can normally block your program |
57 | (e.g. reading from disk) will be done asynchronously: the operation |
38 | (e.g. reading from disk) will be done asynchronously: the operation |
58 | will still block, but you can do something else in the meantime. This |
39 | will still block, but you can do something else in the meantime. This |
59 | is extremely useful for programs that need to stay interactive even |
40 | is extremely useful for programs that need to stay interactive even |
… | |
… | |
61 | etc.), but can also be used to easily do operations in parallel that are |
42 | etc.), but can also be used to easily do operations in parallel that are |
62 | normally done sequentially, e.g. stat'ing many files, which is much faster |
43 | normally done sequentially, e.g. stat'ing many files, which is much faster |
63 | on a RAID volume or over NFS when you do a number of stat operations |
44 | on a RAID volume or over NFS when you do a number of stat operations |
64 | concurrently. |
45 | concurrently. |
65 | |
46 | |
66 | While this works on all types of file descriptors (for example sockets), |
47 | While most of this works on all types of file descriptors (for |
67 | using these functions on file descriptors that support nonblocking |
48 | example sockets), using these functions on file descriptors that |
68 | operation (again, sockets, pipes etc.) is very inefficient. Use an event |
49 | support nonblocking operation (again, sockets, pipes etc.) is |
69 | loop for that (such as the L<Event|Event> module): IO::AIO will naturally |
50 | very inefficient. Use an event loop for that (such as the L<EV> |
70 | fit into such an event loop itself. |
51 | module): IO::AIO will naturally fit into such an event loop itself. |
71 | |
52 | |
72 | In this version, a number of threads are started that execute your |
53 | In this version, a number of threads are started that execute your |
73 | requests and signal their completion. You don't need thread support |
54 | requests and signal their completion. You don't need thread support |
74 | in perl, and the threads created by this module will not be visible |
55 | in perl, and the threads created by this module will not be visible |
75 | to perl. In the future, this module might make use of the native aio |
56 | to perl. In the future, this module might make use of the native aio |
… | |
… | |
77 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
58 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
78 | files currently, for example), and they would only support aio_read and |
59 | files currently, for example), and they would only support aio_read and |
79 | aio_write, so the remaining functionality would have to be implemented |
60 | aio_write, so the remaining functionality would have to be implemented |
80 | using threads anyway. |
61 | using threads anyway. |
81 | |
62 | |
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63 | In addition to asynchronous I/O, this module also exports some rather |
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64 | arcane interfaces, such as C<madvise> or linux's C<splice> system call, |
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65 | which is why the C<A> in C<AIO> can also mean I<advanced>. |
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66 | |
82 | Although the module will work with in the presence of other (Perl-) |
67 | Although the module will work in the presence of other (Perl-) threads, |
83 | threads, it is currently not reentrant in any way, so use appropriate |
68 | it is currently not reentrant in any way, so use appropriate locking |
84 | locking yourself, always call C<poll_cb> from within the same thread, or |
69 | yourself, always call C<poll_cb> from within the same thread, or never |
85 | never call C<poll_cb> (or other C<aio_> functions) recursively. |
70 | call C<poll_cb> (or other C<aio_> functions) recursively. |
86 | |
71 | |
87 | =head2 EXAMPLE |
72 | =head2 EXAMPLE |
88 | |
73 | |
89 | This is a simple example that uses the Event module and loads |
74 | This is a simple example that uses the EV module and loads |
90 | F</etc/passwd> asynchronously: |
75 | F</etc/passwd> asynchronously: |
91 | |
76 | |
92 | use Fcntl; |
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93 | use Event; |
77 | use EV; |
94 | use IO::AIO; |
78 | use IO::AIO; |
95 | |
79 | |
96 | # register the IO::AIO callback with Event |
80 | # register the IO::AIO callback with EV |
97 | Event->io (fd => IO::AIO::poll_fileno, |
81 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
98 | poll => 'r', |
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99 | cb => \&IO::AIO::poll_cb); |
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100 | |
82 | |
101 | # queue the request to open /etc/passwd |
83 | # queue the request to open /etc/passwd |
102 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
84 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
103 | my $fh = $_[0] |
85 | my $fh = shift |
104 | or die "error while opening: $!"; |
86 | or die "error while opening: $!"; |
105 | |
87 | |
106 | # stat'ing filehandles is generally non-blocking |
88 | # stat'ing filehandles is generally non-blocking |
107 | my $size = -s $fh; |
89 | my $size = -s $fh; |
108 | |
90 | |
… | |
… | |
116 | |
98 | |
117 | # file contents now in $contents |
99 | # file contents now in $contents |
118 | print $contents; |
100 | print $contents; |
119 | |
101 | |
120 | # exit event loop and program |
102 | # exit event loop and program |
121 | Event::unloop; |
103 | EV::break; |
122 | }; |
104 | }; |
123 | }; |
105 | }; |
124 | |
106 | |
125 | # possibly queue up other requests, or open GUI windows, |
107 | # possibly queue up other requests, or open GUI windows, |
126 | # check for sockets etc. etc. |
108 | # check for sockets etc. etc. |
127 | |
109 | |
128 | # process events as long as there are some: |
110 | # process events as long as there are some: |
129 | Event::loop; |
111 | EV::run; |
130 | |
112 | |
131 | =head1 REQUEST ANATOMY AND LIFETIME |
113 | =head1 REQUEST ANATOMY AND LIFETIME |
132 | |
114 | |
133 | Every C<aio_*> function creates a request. which is a C data structure not |
115 | Every C<aio_*> function creates a request. which is a C data structure not |
134 | directly visible to Perl. |
116 | directly visible to Perl. |
… | |
… | |
182 | |
164 | |
183 | =cut |
165 | =cut |
184 | |
166 | |
185 | package IO::AIO; |
167 | package IO::AIO; |
186 | |
168 | |
187 | no warnings; |
169 | use Carp (); |
188 | use strict 'vars'; |
170 | |
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171 | use common::sense; |
189 | |
172 | |
190 | use base 'Exporter'; |
173 | use base 'Exporter'; |
191 | |
174 | |
192 | BEGIN { |
175 | BEGIN { |
193 | our $VERSION = '2.1'; |
176 | our $VERSION = 4.76; |
194 | |
177 | |
195 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
178 | our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close |
196 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
179 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
197 | aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
198 | aio_copy aio_group aio_nop aio_mknod); |
181 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
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182 | aio_pathsync aio_readahead aio_fiemap aio_allocate |
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183 | aio_rename aio_rename2 aio_link aio_move aio_copy aio_group |
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184 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
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185 | aio_chmod aio_utime aio_truncate |
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186 | aio_msync aio_mtouch aio_mlock aio_mlockall |
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187 | aio_statvfs |
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188 | aio_slurp |
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189 | aio_wd); |
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190 | |
199 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
191 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
200 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
192 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
201 | min_parallel max_parallel max_idle |
193 | min_parallel max_parallel max_idle idle_timeout |
202 | nreqs nready npending nthreads |
194 | nreqs nready npending nthreads |
203 | max_poll_time max_poll_reqs); |
195 | max_poll_time max_poll_reqs |
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196 | sendfile fadvise madvise |
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197 | mmap munmap mremap munlock munlockall); |
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198 | |
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199 | push @AIO_REQ, qw(aio_busy); # not exported |
204 | |
200 | |
205 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
201 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
206 | |
202 | |
207 | require XSLoader; |
203 | require XSLoader; |
208 | XSLoader::load ("IO::AIO", $VERSION); |
204 | XSLoader::load ("IO::AIO", $VERSION); |
209 | } |
205 | } |
210 | |
206 | |
211 | =head1 FUNCTIONS |
207 | =head1 FUNCTIONS |
212 | |
208 | |
213 | =head2 AIO REQUEST FUNCTIONS |
209 | =head2 QUICK OVERVIEW |
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210 | |
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211 | This section simply lists the prototypes most of the functions for |
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212 | quick reference. See the following sections for function-by-function |
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213 | documentation. |
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214 | |
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215 | aio_wd $pathname, $callback->($wd) |
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216 | aio_open $pathname, $flags, $mode, $callback->($fh) |
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217 | aio_close $fh, $callback->($status) |
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218 | aio_seek $fh,$offset,$whence, $callback->($offs) |
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219 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
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220 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
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221 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
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222 | aio_readahead $fh,$offset,$length, $callback->($retval) |
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223 | aio_stat $fh_or_path, $callback->($status) |
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224 | aio_lstat $fh, $callback->($status) |
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225 | aio_statvfs $fh_or_path, $callback->($statvfs) |
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226 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
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227 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
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228 | aio_chmod $fh_or_path, $mode, $callback->($status) |
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229 | aio_truncate $fh_or_path, $offset, $callback->($status) |
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230 | aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
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231 | aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
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232 | aio_unlink $pathname, $callback->($status) |
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233 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
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234 | aio_link $srcpath, $dstpath, $callback->($status) |
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235 | aio_symlink $srcpath, $dstpath, $callback->($status) |
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236 | aio_readlink $pathname, $callback->($link) |
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237 | aio_realpath $pathname, $callback->($path) |
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238 | aio_rename $srcpath, $dstpath, $callback->($status) |
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239 | aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
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240 | aio_mkdir $pathname, $mode, $callback->($status) |
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241 | aio_rmdir $pathname, $callback->($status) |
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242 | aio_readdir $pathname, $callback->($entries) |
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243 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
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244 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
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245 | IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN |
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246 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
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247 | aio_load $pathname, $data, $callback->($status) |
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248 | aio_copy $srcpath, $dstpath, $callback->($status) |
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249 | aio_move $srcpath, $dstpath, $callback->($status) |
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250 | aio_rmtree $pathname, $callback->($status) |
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251 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
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252 | aio_ioctl $fh, $request, $buf, $callback->($status) |
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253 | aio_sync $callback->($status) |
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254 | aio_syncfs $fh, $callback->($status) |
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255 | aio_fsync $fh, $callback->($status) |
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256 | aio_fdatasync $fh, $callback->($status) |
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257 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
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258 | aio_pathsync $pathname, $callback->($status) |
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259 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
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260 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
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261 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
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262 | aio_mlockall $flags, $callback->($status) |
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263 | aio_group $callback->(...) |
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264 | aio_nop $callback->() |
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265 | |
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266 | $prev_pri = aioreq_pri [$pri] |
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267 | aioreq_nice $pri_adjust |
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268 | |
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269 | IO::AIO::poll_wait |
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270 | IO::AIO::poll_cb |
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271 | IO::AIO::poll |
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272 | IO::AIO::flush |
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273 | IO::AIO::max_poll_reqs $nreqs |
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274 | IO::AIO::max_poll_time $seconds |
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275 | IO::AIO::min_parallel $nthreads |
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276 | IO::AIO::max_parallel $nthreads |
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277 | IO::AIO::max_idle $nthreads |
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278 | IO::AIO::idle_timeout $seconds |
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279 | IO::AIO::max_outstanding $maxreqs |
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280 | IO::AIO::nreqs |
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281 | IO::AIO::nready |
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282 | IO::AIO::npending |
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283 | IO::AIO::reinit |
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284 | |
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285 | $nfd = IO::AIO::get_fdlimit |
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286 | IO::AIO::min_fdlimit $nfd |
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287 | |
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288 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
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289 | IO::AIO::fadvise $fh, $offset, $len, $advice |
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290 | |
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291 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
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292 | IO::AIO::munmap $scalar |
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293 | IO::AIO::mremap $scalar, $new_length, $flags[, $new_address] |
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294 | IO::AIO::madvise $scalar, $offset, $length, $advice |
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295 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
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296 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
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297 | IO::AIO::munlockall |
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298 | |
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299 | # stat extensions |
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300 | $counter = IO::AIO::st_gen |
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301 | $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime |
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302 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime |
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303 | $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec |
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304 | $seconds = IO::AIO::st_btimesec |
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305 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec |
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306 | |
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307 | # very much unportable syscalls |
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308 | IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_len, $flags |
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309 | IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
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310 | IO::AIO::tee $r_fh, $w_fh, $length, $flags |
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311 | $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
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312 | ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
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313 | $fh = IO::AIO::memfd_create $pathname[, $flags] |
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314 | $fh = IO::AIO::eventfd [$initval, [$flags]] |
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315 | $fh = IO::AIO::timerfd_create $clockid[, $flags] |
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316 | ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value |
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317 | ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
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318 | |
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319 | =head2 API NOTES |
214 | |
320 | |
215 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
321 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
216 | with the same name (sans C<aio_>). The arguments are similar or identical, |
322 | with the same name (sans C<aio_>). The arguments are similar or identical, |
217 | and they all accept an additional (and optional) C<$callback> argument |
323 | and they all accept an additional (and optional) C<$callback> argument |
218 | which must be a code reference. This code reference will get called with |
324 | which must be a code reference. This code reference will be called after |
219 | the syscall return code (e.g. most syscalls return C<-1> on error, unlike |
325 | the syscall has been executed in an asynchronous fashion. The results |
220 | perl, which usually delivers "false") as it's sole argument when the given |
326 | of the request will be passed as arguments to the callback (and, if an |
221 | syscall has been executed asynchronously. |
327 | error occured, in C<$!>) - for most requests the syscall return code (e.g. |
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328 | most syscalls return C<-1> on error, unlike perl, which usually delivers |
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329 | "false"). |
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330 | |
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331 | Some requests (such as C<aio_readdir>) pass the actual results and |
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332 | communicate failures by passing C<undef>. |
222 | |
333 | |
223 | All functions expecting a filehandle keep a copy of the filehandle |
334 | All functions expecting a filehandle keep a copy of the filehandle |
224 | internally until the request has finished. |
335 | internally until the request has finished. |
225 | |
336 | |
226 | All functions return request objects of type L<IO::AIO::REQ> that allow |
337 | All functions return request objects of type L<IO::AIO::REQ> that allow |
227 | further manipulation of those requests while they are in-flight. |
338 | further manipulation of those requests while they are in-flight. |
228 | |
339 | |
229 | The pathnames you pass to these routines I<must> be absolute and |
340 | The pathnames you pass to these routines I<should> be absolute. The |
230 | encoded as octets. The reason for the former is that at the time the |
341 | reason for this is that at the time the request is being executed, the |
231 | request is being executed, the current working directory could have |
342 | current working directory could have changed. Alternatively, you can |
232 | changed. Alternatively, you can make sure that you never change the |
343 | make sure that you never change the current working directory anywhere |
233 | current working directory anywhere in the program and then use relative |
344 | in the program and then use relative paths. You can also take advantage |
234 | paths. |
345 | of IO::AIOs working directory abstraction, that lets you specify paths |
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346 | relative to some previously-opened "working directory object" - see the |
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347 | description of the C<IO::AIO::WD> class later in this document. |
235 | |
348 | |
236 | To encode pathnames as octets, either make sure you either: a) always pass |
349 | To encode pathnames as octets, either make sure you either: a) always pass |
237 | in filenames you got from outside (command line, readdir etc.) without |
350 | in filenames you got from outside (command line, readdir etc.) without |
238 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
351 | tinkering, b) are in your native filesystem encoding, c) use the Encode |
239 | your pathnames to the locale (or other) encoding in effect in the user |
352 | module and encode your pathnames to the locale (or other) encoding in |
240 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
353 | effect in the user environment, d) use Glib::filename_from_unicode on |
241 | use something else to ensure your scalar has the correct contents. |
354 | unicode filenames or e) use something else to ensure your scalar has the |
|
|
355 | correct contents. |
242 | |
356 | |
243 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
357 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
244 | handles correctly wether it is set or not. |
358 | handles correctly whether it is set or not. |
|
|
359 | |
|
|
360 | =head2 AIO REQUEST FUNCTIONS |
245 | |
361 | |
246 | =over 4 |
362 | =over 4 |
247 | |
363 | |
248 | =item $prev_pri = aioreq_pri [$pri] |
364 | =item $prev_pri = aioreq_pri [$pri] |
249 | |
365 | |
… | |
… | |
269 | aio_read $_[0], ..., sub { |
385 | aio_read $_[0], ..., sub { |
270 | ... |
386 | ... |
271 | }; |
387 | }; |
272 | }; |
388 | }; |
273 | |
389 | |
|
|
390 | |
274 | =item aioreq_nice $pri_adjust |
391 | =item aioreq_nice $pri_adjust |
275 | |
392 | |
276 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
393 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
277 | priority, so the effect is cumulative. |
394 | priority, so the effect is cumulative. |
278 | |
395 | |
|
|
396 | |
279 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
397 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
280 | |
398 | |
281 | Asynchronously open or create a file and call the callback with a newly |
399 | Asynchronously open or create a file and call the callback with a newly |
282 | created filehandle for the file. |
400 | created filehandle for the file (or C<undef> in case of an error). |
283 | |
401 | |
284 | The pathname passed to C<aio_open> must be absolute. See API NOTES, above, |
402 | The pathname passed to C<aio_open> must be absolute. See API NOTES, above, |
285 | for an explanation. |
403 | for an explanation. |
286 | |
404 | |
287 | The C<$flags> argument is a bitmask. See the C<Fcntl> module for a |
405 | The C<$flags> argument is a bitmask. See the C<Fcntl> module for a |
288 | list. They are the same as used by C<sysopen>. |
406 | list. They are the same as used by C<sysopen>. |
289 | |
407 | |
290 | Likewise, C<$mode> specifies the mode of the newly created file, if it |
408 | Likewise, C<$mode> specifies the mode of the newly created file, if it |
291 | didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>, |
409 | didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>, |
292 | except that it is mandatory (i.e. use C<0> if you don't create new files, |
410 | except that it is mandatory (i.e. use C<0> if you don't create new files, |
293 | and C<0666> or C<0777> if you do). |
411 | and C<0666> or C<0777> if you do). Note that the C<$mode> will be modified |
|
|
412 | by the umask in effect then the request is being executed, so better never |
|
|
413 | change the umask. |
294 | |
414 | |
295 | Example: |
415 | Example: |
296 | |
416 | |
297 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
417 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
298 | if ($_[0]) { |
418 | if ($_[0]) { |
299 | print "open successful, fh is $_[0]\n"; |
419 | print "open successful, fh is $_[0]\n"; |
300 | ... |
420 | ... |
301 | } else { |
421 | } else { |
302 | die "open failed: $!\n"; |
422 | die "open failed: $!\n"; |
303 | } |
423 | } |
304 | }; |
424 | }; |
305 | |
425 | |
|
|
426 | In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>, |
|
|
427 | C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the |
|
|
428 | following POSIX and non-POSIX constants are available (missing ones on |
|
|
429 | your system are, as usual, C<0>): |
|
|
430 | |
|
|
431 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
|
|
432 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
|
|
433 | C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, C<O_TTY_INIT> and C<O_ACCMODE>. |
|
|
434 | |
|
|
435 | |
306 | =item aio_close $fh, $callback->($status) |
436 | =item aio_close $fh, $callback->($status) |
307 | |
437 | |
308 | Asynchronously close a file and call the callback with the result |
438 | Asynchronously close a file and call the callback with the result |
309 | code. I<WARNING:> although accepted, you should not pass in a perl |
439 | code. |
310 | filehandle here, as perl will likely close the file descriptor another |
|
|
311 | time when the filehandle is destroyed. Normally, you can safely call perls |
|
|
312 | C<close> or just let filehandles go out of scope. |
|
|
313 | |
440 | |
314 | This is supposed to be a bug in the API, so that might change. It's |
441 | Unfortunately, you can't do this to perl. Perl I<insists> very strongly on |
315 | therefore best to avoid this function. |
442 | closing the file descriptor associated with the filehandle itself. |
|
|
443 | |
|
|
444 | Therefore, C<aio_close> will not close the filehandle - instead it will |
|
|
445 | use dup2 to overwrite the file descriptor with the write-end of a pipe |
|
|
446 | (the pipe fd will be created on demand and will be cached). |
|
|
447 | |
|
|
448 | Or in other words: the file descriptor will be closed, but it will not be |
|
|
449 | free for reuse until the perl filehandle is closed. |
|
|
450 | |
|
|
451 | =cut |
|
|
452 | |
|
|
453 | =item aio_seek $fh, $offset, $whence, $callback->($offs) |
|
|
454 | |
|
|
455 | Seeks the filehandle to the new C<$offset>, similarly to perl's |
|
|
456 | C<sysseek>. The C<$whence> can use the traditional values (C<0> for |
|
|
457 | C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for |
|
|
458 | C<IO::AIO::SEEK_END>). |
|
|
459 | |
|
|
460 | The resulting absolute offset will be passed to the callback, or C<-1> in |
|
|
461 | case of an error. |
|
|
462 | |
|
|
463 | In theory, the C<$whence> constants could be different than the |
|
|
464 | corresponding values from L<Fcntl>, but perl guarantees they are the same, |
|
|
465 | so don't panic. |
|
|
466 | |
|
|
467 | As a GNU/Linux (and maybe Solaris) extension, also the constants |
|
|
468 | C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they |
|
|
469 | could be found. No guarantees about suitability for use in C<aio_seek> or |
|
|
470 | Perl's C<sysseek> can be made though, although I would naively assume they |
|
|
471 | "just work". |
316 | |
472 | |
317 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
473 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
318 | |
474 | |
319 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
475 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
320 | |
476 | |
321 | Reads or writes C<length> bytes from the specified C<fh> and C<offset> |
477 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
322 | into the scalar given by C<data> and offset C<dataoffset> and calls the |
478 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and |
323 | callback without the actual number of bytes read (or -1 on error, just |
479 | calls the callback with the actual number of bytes transferred (or -1 on |
324 | like the syscall). |
480 | error, just like the syscall). |
|
|
481 | |
|
|
482 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
|
|
483 | offset plus the actual number of bytes read. |
|
|
484 | |
|
|
485 | If C<$offset> is undefined, then the current file descriptor offset will |
|
|
486 | be used (and updated), otherwise the file descriptor offset will not be |
|
|
487 | changed by these calls. |
|
|
488 | |
|
|
489 | If C<$length> is undefined in C<aio_write>, use the remaining length of |
|
|
490 | C<$data>. |
|
|
491 | |
|
|
492 | If C<$dataoffset> is less than zero, it will be counted from the end of |
|
|
493 | C<$data>. |
325 | |
494 | |
326 | The C<$data> scalar I<MUST NOT> be modified in any way while the request |
495 | The C<$data> scalar I<MUST NOT> be modified in any way while the request |
327 | is outstanding. Modifying it can result in segfaults or WW3 (if the |
496 | is outstanding. Modifying it can result in segfaults or World War III (if |
328 | necessary/optional hardware is installed). |
497 | the necessary/optional hardware is installed). |
329 | |
498 | |
330 | Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at |
499 | Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at |
331 | offset C<0> within the scalar: |
500 | offset C<0> within the scalar: |
332 | |
501 | |
333 | aio_read $fh, 7, 15, $buffer, 0, sub { |
502 | aio_read $fh, 7, 15, $buffer, 0, sub { |
334 | $_[0] > 0 or die "read error: $!"; |
503 | $_[0] > 0 or die "read error: $!"; |
335 | print "read $_[0] bytes: <$buffer>\n"; |
504 | print "read $_[0] bytes: <$buffer>\n"; |
336 | }; |
505 | }; |
337 | |
506 | |
|
|
507 | |
338 | =item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
508 | =item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
339 | |
509 | |
340 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
510 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
341 | reading at byte offset C<$in_offset>, and starts writing at the current |
511 | reading at byte offset C<$in_offset>, and starts writing at the current |
342 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
512 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
343 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
513 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
344 | other. |
514 | other. The same C<$in_fh> works fine though, as this function does not |
|
|
515 | move or use the file offset of C<$in_fh>. |
345 | |
516 | |
|
|
517 | Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than |
|
|
518 | are written, and there is no way to find out how many more bytes have been |
|
|
519 | read from C<aio_sendfile> alone, as C<aio_sendfile> only provides the |
|
|
520 | number of bytes written to C<$out_fh>. Only if the result value equals |
|
|
521 | C<$length> one can assume that C<$length> bytes have been read. |
|
|
522 | |
|
|
523 | Unlike with other C<aio_> functions, it makes a lot of sense to use |
|
|
524 | C<aio_sendfile> on non-blocking sockets, as long as one end (typically |
|
|
525 | the C<$in_fh>) is a file - the file I/O will then be asynchronous, while |
|
|
526 | the socket I/O will be non-blocking. Note, however, that you can run |
|
|
527 | into a trap where C<aio_sendfile> reads some data with readahead, then |
|
|
528 | fails to write all data, and when the socket is ready the next time, the |
|
|
529 | data in the cache is already lost, forcing C<aio_sendfile> to again hit |
|
|
530 | the disk. Explicit C<aio_read> + C<aio_write> let's you better control |
|
|
531 | resource usage. |
|
|
532 | |
346 | This call tries to make use of a native C<sendfile> syscall to provide |
533 | This call tries to make use of a native C<sendfile>-like syscall to |
347 | zero-copy operation. For this to work, C<$out_fh> should refer to a |
534 | provide zero-copy operation. For this to work, C<$out_fh> should refer to |
348 | socket, and C<$in_fh> should refer to mmap'able file. |
535 | a socket, and C<$in_fh> should refer to an mmap'able file. |
349 | |
536 | |
350 | If the native sendfile call fails or is not implemented, it will be |
537 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
351 | emulated, so you can call C<aio_sendfile> on any type of filehandle |
538 | C<EINVAL>, C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or |
|
|
539 | C<ENOTSOCK>, it will be emulated, so you can call C<aio_sendfile> on any |
352 | regardless of the limitations of the operating system. |
540 | type of filehandle regardless of the limitations of the operating system. |
353 | |
541 | |
354 | Please note, however, that C<aio_sendfile> can read more bytes from |
542 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
355 | C<$in_fh> than are written, and there is no way to find out how many |
543 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
356 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
544 | on many systems, this implementation tries to work around some known bugs |
357 | provides the number of bytes written to C<$out_fh>. Only if the result |
545 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
358 | value equals C<$length> one can assume that C<$length> bytes have been |
546 | so you really really should check the return value of C<aio_sendfile> - |
359 | read. |
547 | fewer bytes than expected might have been transferred. |
|
|
548 | |
360 | |
549 | |
361 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
550 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
362 | |
551 | |
363 | C<aio_readahead> populates the page cache with data from a file so that |
552 | C<aio_readahead> populates the page cache with data from a file so that |
364 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
553 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
… | |
… | |
367 | whole pages, so that offset is effectively rounded down to a page boundary |
556 | whole pages, so that offset is effectively rounded down to a page boundary |
368 | and bytes are read up to the next page boundary greater than or equal to |
557 | and bytes are read up to the next page boundary greater than or equal to |
369 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
558 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
370 | file. The current file offset of the file is left unchanged. |
559 | file. The current file offset of the file is left unchanged. |
371 | |
560 | |
372 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
561 | If that syscall doesn't exist (likely if your kernel isn't Linux) it will |
373 | emulated by simply reading the data, which would have a similar effect. |
562 | be emulated by simply reading the data, which would have a similar effect. |
|
|
563 | |
374 | |
564 | |
375 | =item aio_stat $fh_or_path, $callback->($status) |
565 | =item aio_stat $fh_or_path, $callback->($status) |
376 | |
566 | |
377 | =item aio_lstat $fh, $callback->($status) |
567 | =item aio_lstat $fh, $callback->($status) |
378 | |
568 | |
379 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
569 | Works almost exactly like perl's C<stat> or C<lstat> in void context. The |
380 | be called after the stat and the results will be available using C<stat _> |
570 | callback will be called after the stat and the results will be available |
381 | or C<-s _> etc... |
571 | using C<stat _> or C<-s _> and other tests (with the exception of C<-B> |
|
|
572 | and C<-T>). |
382 | |
573 | |
383 | The pathname passed to C<aio_stat> must be absolute. See API NOTES, above, |
574 | The pathname passed to C<aio_stat> must be absolute. See API NOTES, above, |
384 | for an explanation. |
575 | for an explanation. |
385 | |
576 | |
386 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
577 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
387 | error when stat'ing a large file, the results will be silently truncated |
578 | error when stat'ing a large file, the results will be silently truncated |
388 | unless perl itself is compiled with large file support. |
579 | unless perl itself is compiled with large file support. |
|
|
580 | |
|
|
581 | To help interpret the mode and dev/rdev stat values, IO::AIO offers the |
|
|
582 | following constants and functions (if not implemented, the constants will |
|
|
583 | be C<0> and the functions will either C<croak> or fall back on traditional |
|
|
584 | behaviour). |
|
|
585 | |
|
|
586 | C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>, |
|
|
587 | C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>, |
|
|
588 | C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>. |
|
|
589 | |
|
|
590 | To access higher resolution stat timestamps, see L<SUBSECOND STAT TIME |
|
|
591 | ACCESS>. |
389 | |
592 | |
390 | Example: Print the length of F</etc/passwd>: |
593 | Example: Print the length of F</etc/passwd>: |
391 | |
594 | |
392 | aio_stat "/etc/passwd", sub { |
595 | aio_stat "/etc/passwd", sub { |
393 | $_[0] and die "stat failed: $!"; |
596 | $_[0] and die "stat failed: $!"; |
394 | print "size is ", -s _, "\n"; |
597 | print "size is ", -s _, "\n"; |
395 | }; |
598 | }; |
396 | |
599 | |
|
|
600 | |
|
|
601 | =item aio_statvfs $fh_or_path, $callback->($statvfs) |
|
|
602 | |
|
|
603 | Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on |
|
|
604 | whether a file handle or path was passed. |
|
|
605 | |
|
|
606 | On success, the callback is passed a hash reference with the following |
|
|
607 | members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>, |
|
|
608 | C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef> |
|
|
609 | is passed. |
|
|
610 | |
|
|
611 | The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and |
|
|
612 | C<ST_NOSUID>. |
|
|
613 | |
|
|
614 | The following non-POSIX IO::AIO::ST_* flag masks are defined to |
|
|
615 | their correct value when available, or to C<0> on systems that do |
|
|
616 | not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>, |
|
|
617 | C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>, |
|
|
618 | C<ST_NODIRATIME> and C<ST_RELATIME>. |
|
|
619 | |
|
|
620 | Example: stat C</wd> and dump out the data if successful. |
|
|
621 | |
|
|
622 | aio_statvfs "/wd", sub { |
|
|
623 | my $f = $_[0] |
|
|
624 | or die "statvfs: $!"; |
|
|
625 | |
|
|
626 | use Data::Dumper; |
|
|
627 | say Dumper $f; |
|
|
628 | }; |
|
|
629 | |
|
|
630 | # result: |
|
|
631 | { |
|
|
632 | bsize => 1024, |
|
|
633 | bfree => 4333064312, |
|
|
634 | blocks => 10253828096, |
|
|
635 | files => 2050765568, |
|
|
636 | flag => 4096, |
|
|
637 | favail => 2042092649, |
|
|
638 | bavail => 4333064312, |
|
|
639 | ffree => 2042092649, |
|
|
640 | namemax => 255, |
|
|
641 | frsize => 1024, |
|
|
642 | fsid => 1810 |
|
|
643 | } |
|
|
644 | |
|
|
645 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
|
|
646 | |
|
|
647 | Works like perl's C<utime> function (including the special case of $atime |
|
|
648 | and $mtime being undef). Fractional times are supported if the underlying |
|
|
649 | syscalls support them. |
|
|
650 | |
|
|
651 | When called with a pathname, uses utimensat(2) or utimes(2) if available, |
|
|
652 | otherwise utime(2). If called on a file descriptor, uses futimens(2) |
|
|
653 | or futimes(2) if available, otherwise returns ENOSYS, so this is not |
|
|
654 | portable. |
|
|
655 | |
|
|
656 | Examples: |
|
|
657 | |
|
|
658 | # set atime and mtime to current time (basically touch(1)): |
|
|
659 | aio_utime "path", undef, undef; |
|
|
660 | # set atime to current time and mtime to beginning of the epoch: |
|
|
661 | aio_utime "path", time, undef; # undef==0 |
|
|
662 | |
|
|
663 | |
|
|
664 | =item aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
|
|
665 | |
|
|
666 | Works like perl's C<chown> function, except that C<undef> for either $uid |
|
|
667 | or $gid is being interpreted as "do not change" (but -1 can also be used). |
|
|
668 | |
|
|
669 | Examples: |
|
|
670 | |
|
|
671 | # same as "chown root path" in the shell: |
|
|
672 | aio_chown "path", 0, -1; |
|
|
673 | # same as above: |
|
|
674 | aio_chown "path", 0, undef; |
|
|
675 | |
|
|
676 | |
|
|
677 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
|
|
678 | |
|
|
679 | Works like truncate(2) or ftruncate(2). |
|
|
680 | |
|
|
681 | |
|
|
682 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
|
|
683 | |
|
|
684 | Allocates or frees disk space according to the C<$mode> argument. See the |
|
|
685 | linux C<fallocate> documentation for details. |
|
|
686 | |
|
|
687 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
|
|
688 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
|
|
689 | to deallocate a file range. |
|
|
690 | |
|
|
691 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
|
|
692 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
|
|
693 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
|
|
694 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
|
|
695 | |
|
|
696 | The file system block size used by C<fallocate> is presumably the |
|
|
697 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
|
|
698 | can dictate other limitations. |
|
|
699 | |
|
|
700 | If C<fallocate> isn't available or cannot be emulated (currently no |
|
|
701 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
|
|
702 | |
|
|
703 | |
|
|
704 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
|
|
705 | |
|
|
706 | Works like perl's C<chmod> function. |
|
|
707 | |
|
|
708 | |
397 | =item aio_unlink $pathname, $callback->($status) |
709 | =item aio_unlink $pathname, $callback->($status) |
398 | |
710 | |
399 | Asynchronously unlink (delete) a file and call the callback with the |
711 | Asynchronously unlink (delete) a file and call the callback with the |
400 | result code. |
712 | result code. |
401 | |
713 | |
|
|
714 | |
402 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
715 | =item aio_mknod $pathname, $mode, $dev, $callback->($status) |
403 | |
716 | |
404 | [EXPERIMENTAL] |
717 | [EXPERIMENTAL] |
405 | |
718 | |
406 | Asynchronously create a device node (or fifo). See mknod(2). |
719 | Asynchronously create a device node (or fifo). See mknod(2). |
407 | |
720 | |
408 | The only (POSIX-) portable way of calling this function is: |
721 | The only (POSIX-) portable way of calling this function is: |
409 | |
722 | |
410 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
723 | aio_mknod $pathname, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
|
|
724 | |
|
|
725 | See C<aio_stat> for info about some potentially helpful extra constants |
|
|
726 | and functions. |
411 | |
727 | |
412 | =item aio_link $srcpath, $dstpath, $callback->($status) |
728 | =item aio_link $srcpath, $dstpath, $callback->($status) |
413 | |
729 | |
414 | Asynchronously create a new link to the existing object at C<$srcpath> at |
730 | Asynchronously create a new link to the existing object at C<$srcpath> at |
415 | the path C<$dstpath> and call the callback with the result code. |
731 | the path C<$dstpath> and call the callback with the result code. |
416 | |
732 | |
|
|
733 | |
417 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
734 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
418 | |
735 | |
419 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
736 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
420 | the path C<$dstpath> and call the callback with the result code. |
737 | the path C<$dstpath> and call the callback with the result code. |
421 | |
738 | |
|
|
739 | |
|
|
740 | =item aio_readlink $pathname, $callback->($link) |
|
|
741 | |
|
|
742 | Asynchronously read the symlink specified by C<$path> and pass it to |
|
|
743 | the callback. If an error occurs, nothing or undef gets passed to the |
|
|
744 | callback. |
|
|
745 | |
|
|
746 | |
|
|
747 | =item aio_realpath $pathname, $callback->($path) |
|
|
748 | |
|
|
749 | Asynchronously make the path absolute and resolve any symlinks in |
|
|
750 | C<$path>. The resulting path only consists of directories (same as |
|
|
751 | L<Cwd::realpath>). |
|
|
752 | |
|
|
753 | This request can be used to get the absolute path of the current working |
|
|
754 | directory by passing it a path of F<.> (a single dot). |
|
|
755 | |
|
|
756 | |
422 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
757 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
423 | |
758 | |
424 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
759 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
425 | rename(2) and call the callback with the result code. |
760 | rename(2) and call the callback with the result code. |
426 | |
761 | |
|
|
762 | On systems that support the AIO::WD working directory abstraction |
|
|
763 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
|
|
764 | of failing, C<rename> is called on the absolute path of C<$wd>. |
|
|
765 | |
|
|
766 | |
|
|
767 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
|
|
768 | |
|
|
769 | Basically a version of C<aio_rename> with an additional C<$flags> |
|
|
770 | argument. Calling this with C<$flags=0> is the same as calling |
|
|
771 | C<aio_rename>. |
|
|
772 | |
|
|
773 | Non-zero flags are currently only supported on GNU/Linux systems that |
|
|
774 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
|
|
775 | |
|
|
776 | The following constants are available (missing ones are, as usual C<0>), |
|
|
777 | see renameat2(2) for details: |
|
|
778 | |
|
|
779 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
|
|
780 | and C<IO::AIO::RENAME_WHITEOUT>. |
|
|
781 | |
|
|
782 | |
|
|
783 | =item aio_mkdir $pathname, $mode, $callback->($status) |
|
|
784 | |
|
|
785 | Asynchronously mkdir (create) a directory and call the callback with |
|
|
786 | the result code. C<$mode> will be modified by the umask at the time the |
|
|
787 | request is executed, so do not change your umask. |
|
|
788 | |
|
|
789 | |
427 | =item aio_rmdir $pathname, $callback->($status) |
790 | =item aio_rmdir $pathname, $callback->($status) |
428 | |
791 | |
429 | Asynchronously rmdir (delete) a directory and call the callback with the |
792 | Asynchronously rmdir (delete) a directory and call the callback with the |
430 | result code. |
793 | result code. |
|
|
794 | |
|
|
795 | On systems that support the AIO::WD working directory abstraction |
|
|
796 | natively, the case C<[$wd, "."]> is specialcased - instead of failing, |
|
|
797 | C<rmdir> is called on the absolute path of C<$wd>. |
|
|
798 | |
431 | |
799 | |
432 | =item aio_readdir $pathname, $callback->($entries) |
800 | =item aio_readdir $pathname, $callback->($entries) |
433 | |
801 | |
434 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
802 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
435 | directory (i.e. opendir + readdir + closedir). The entries will not be |
803 | directory (i.e. opendir + readdir + closedir). The entries will not be |
436 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
804 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
437 | |
805 | |
438 | The callback a single argument which is either C<undef> or an array-ref |
806 | The callback is passed a single argument which is either C<undef> or an |
439 | with the filenames. |
807 | array-ref with the filenames. |
|
|
808 | |
|
|
809 | |
|
|
810 | =item aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
|
|
811 | |
|
|
812 | Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to |
|
|
813 | tune behaviour and output format. In case of an error, C<$entries> will be |
|
|
814 | C<undef>. |
|
|
815 | |
|
|
816 | The flags are a combination of the following constants, ORed together (the |
|
|
817 | flags will also be passed to the callback, possibly modified): |
|
|
818 | |
|
|
819 | =over 4 |
|
|
820 | |
|
|
821 | =item IO::AIO::READDIR_DENTS |
|
|
822 | |
|
|
823 | Normally the callback gets an arrayref consisting of names only (as |
|
|
824 | with C<aio_readdir>). If this flag is set, then the callback gets an |
|
|
825 | arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a |
|
|
826 | single directory entry in more detail: |
|
|
827 | |
|
|
828 | C<$name> is the name of the entry. |
|
|
829 | |
|
|
830 | C<$type> is one of the C<IO::AIO::DT_xxx> constants: |
|
|
831 | |
|
|
832 | C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>, |
|
|
833 | C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>, |
|
|
834 | C<IO::AIO::DT_WHT>. |
|
|
835 | |
|
|
836 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need |
|
|
837 | to know, you have to run stat yourself. Also, for speed/memory reasons, |
|
|
838 | the C<$type> scalars are read-only: you must not modify them. |
|
|
839 | |
|
|
840 | C<$inode> is the inode number (which might not be exact on systems with 64 |
|
|
841 | bit inode numbers and 32 bit perls). This field has unspecified content on |
|
|
842 | systems that do not deliver the inode information. |
|
|
843 | |
|
|
844 | =item IO::AIO::READDIR_DIRS_FIRST |
|
|
845 | |
|
|
846 | When this flag is set, then the names will be returned in an order where |
|
|
847 | likely directories come first, in optimal stat order. This is useful when |
|
|
848 | you need to quickly find directories, or you want to find all directories |
|
|
849 | while avoiding to stat() each entry. |
|
|
850 | |
|
|
851 | If the system returns type information in readdir, then this is used |
|
|
852 | to find directories directly. Otherwise, likely directories are names |
|
|
853 | beginning with ".", or otherwise names with no dots, of which names with |
|
|
854 | short names are tried first. |
|
|
855 | |
|
|
856 | =item IO::AIO::READDIR_STAT_ORDER |
|
|
857 | |
|
|
858 | When this flag is set, then the names will be returned in an order |
|
|
859 | suitable for stat()'ing each one. That is, when you plan to stat() most or |
|
|
860 | all files in the given directory, then the returned order will likely be |
|
|
861 | faster. |
|
|
862 | |
|
|
863 | If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, |
|
|
864 | then the likely dirs come first, resulting in a less optimal stat order |
|
|
865 | for stat'ing all entries, but likely a more optimal order for finding |
|
|
866 | subdirectories. |
|
|
867 | |
|
|
868 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
|
|
869 | |
|
|
870 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
|
|
871 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
|
|
872 | C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all |
|
|
873 | C<$type>'s are known, which can be used to speed up some algorithms. |
|
|
874 | |
|
|
875 | =back |
|
|
876 | |
|
|
877 | |
|
|
878 | =item aio_slurp $pathname, $offset, $length, $data, $callback->($status) |
|
|
879 | |
|
|
880 | Opens, reads and closes the given file. The data is put into C<$data>, |
|
|
881 | which is resized as required. |
|
|
882 | |
|
|
883 | If C<$offset> is negative, then it is counted from the end of the file. |
|
|
884 | |
|
|
885 | If C<$length> is zero, then the remaining length of the file is |
|
|
886 | used. Also, in this case, the same limitations to modifying C<$data> apply |
|
|
887 | as when IO::AIO::mmap is used, i.e. it must only be modified in-place |
|
|
888 | with C<substr>. If the size of the file is known, specifying a non-zero |
|
|
889 | C<$length> results in a performance advantage. |
|
|
890 | |
|
|
891 | This request is similar to the older C<aio_load> request, but since it is |
|
|
892 | a single request, it might be more efficient to use. |
|
|
893 | |
|
|
894 | Example: load F</etc/passwd> into C<$passwd>. |
|
|
895 | |
|
|
896 | my $passwd; |
|
|
897 | aio_slurp "/etc/passwd", 0, 0, $passwd, sub { |
|
|
898 | $_[0] >= 0 |
|
|
899 | or die "/etc/passwd: $!\n"; |
|
|
900 | |
|
|
901 | printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd; |
|
|
902 | print $passwd; |
|
|
903 | }; |
|
|
904 | IO::AIO::flush; |
|
|
905 | |
|
|
906 | |
|
|
907 | =item aio_load $pathname, $data, $callback->($status) |
|
|
908 | |
|
|
909 | This is a composite request that tries to fully load the given file into |
|
|
910 | memory. Status is the same as with aio_read. |
|
|
911 | |
|
|
912 | Using C<aio_slurp> might be more efficient, as it is a single request. |
|
|
913 | |
|
|
914 | =cut |
|
|
915 | |
|
|
916 | sub aio_load($$;$) { |
|
|
917 | my ($path, undef, $cb) = @_; |
|
|
918 | my $data = \$_[1]; |
|
|
919 | |
|
|
920 | my $pri = aioreq_pri; |
|
|
921 | my $grp = aio_group $cb; |
|
|
922 | |
|
|
923 | aioreq_pri $pri; |
|
|
924 | add $grp aio_open $path, O_RDONLY, 0, sub { |
|
|
925 | my $fh = shift |
|
|
926 | or return $grp->result (-1); |
|
|
927 | |
|
|
928 | aioreq_pri $pri; |
|
|
929 | add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub { |
|
|
930 | $grp->result ($_[0]); |
|
|
931 | }; |
|
|
932 | }; |
|
|
933 | |
|
|
934 | $grp |
|
|
935 | } |
440 | |
936 | |
441 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
937 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
442 | |
938 | |
443 | Try to copy the I<file> (directories not supported as either source or |
939 | Try to copy the I<file> (directories not supported as either source or |
444 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
940 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
445 | the C<0> (error) or C<-1> ok. |
941 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
446 | |
942 | |
|
|
943 | Existing destination files will be truncated. |
|
|
944 | |
447 | This is a composite request that it creates the destination file with |
945 | This is a composite request that creates the destination file with |
448 | mode 0200 and copies the contents of the source file into it using |
946 | mode 0200 and copies the contents of the source file into it using |
449 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
947 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
450 | uid/gid, in that order. |
948 | uid/gid, in that order. |
451 | |
949 | |
452 | If an error occurs, the partial destination file will be unlinked, if |
950 | If an error occurs, the partial destination file will be unlinked, if |
… | |
… | |
462 | my $grp = aio_group $cb; |
960 | my $grp = aio_group $cb; |
463 | |
961 | |
464 | aioreq_pri $pri; |
962 | aioreq_pri $pri; |
465 | add $grp aio_open $src, O_RDONLY, 0, sub { |
963 | add $grp aio_open $src, O_RDONLY, 0, sub { |
466 | if (my $src_fh = $_[0]) { |
964 | if (my $src_fh = $_[0]) { |
467 | my @stat = stat $src_fh; |
965 | my @stat = stat $src_fh; # hmm, might block over nfs? |
468 | |
966 | |
469 | aioreq_pri $pri; |
967 | aioreq_pri $pri; |
470 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
968 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
471 | if (my $dst_fh = $_[0]) { |
969 | if (my $dst_fh = $_[0]) { |
472 | aioreq_pri $pri; |
970 | aioreq_pri $pri; |
473 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
971 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
474 | if ($_[0] == $stat[7]) { |
972 | if ($_[0] == $stat[7]) { |
475 | $grp->result (0); |
973 | $grp->result (0); |
476 | close $src_fh; |
974 | close $src_fh; |
477 | |
975 | |
478 | # those should not normally block. should. should. |
976 | my $ch = sub { |
|
|
977 | aioreq_pri $pri; |
|
|
978 | add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub { |
|
|
979 | aioreq_pri $pri; |
|
|
980 | add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub { |
|
|
981 | aioreq_pri $pri; |
|
|
982 | add $grp aio_close $dst_fh; |
|
|
983 | } |
|
|
984 | }; |
|
|
985 | }; |
|
|
986 | |
|
|
987 | aioreq_pri $pri; |
|
|
988 | add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub { |
|
|
989 | if ($_[0] < 0 && $! == ENOSYS) { |
|
|
990 | aioreq_pri $pri; |
479 | utime $stat[8], $stat[9], $dst; |
991 | add $grp aio_utime $dst, $stat[8], $stat[9], $ch; |
480 | chmod $stat[2] & 07777, $dst_fh; |
992 | } else { |
481 | chown $stat[4], $stat[5], $dst_fh; |
993 | $ch->(); |
|
|
994 | } |
482 | close $dst_fh; |
995 | }; |
483 | } else { |
996 | } else { |
484 | $grp->result (-1); |
997 | $grp->result (-1); |
485 | close $src_fh; |
998 | close $src_fh; |
486 | close $dst_fh; |
999 | close $dst_fh; |
487 | |
1000 | |
… | |
… | |
504 | |
1017 | |
505 | =item aio_move $srcpath, $dstpath, $callback->($status) |
1018 | =item aio_move $srcpath, $dstpath, $callback->($status) |
506 | |
1019 | |
507 | Try to move the I<file> (directories not supported as either source or |
1020 | Try to move the I<file> (directories not supported as either source or |
508 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
1021 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
509 | the C<0> (error) or C<-1> ok. |
1022 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
510 | |
1023 | |
511 | This is a composite request that tries to rename(2) the file first. If |
1024 | This is a composite request that tries to rename(2) the file first; if |
512 | rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if |
1025 | rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if |
513 | that is successful, unlinking the C<$srcpath>. |
1026 | that is successful, unlinks the C<$srcpath>. |
514 | |
1027 | |
515 | =cut |
1028 | =cut |
516 | |
1029 | |
517 | sub aio_move($$;$) { |
1030 | sub aio_move($$;$) { |
518 | my ($src, $dst, $cb) = @_; |
1031 | my ($src, $dst, $cb) = @_; |
… | |
… | |
525 | if ($_[0] && $! == EXDEV) { |
1038 | if ($_[0] && $! == EXDEV) { |
526 | aioreq_pri $pri; |
1039 | aioreq_pri $pri; |
527 | add $grp aio_copy $src, $dst, sub { |
1040 | add $grp aio_copy $src, $dst, sub { |
528 | $grp->result ($_[0]); |
1041 | $grp->result ($_[0]); |
529 | |
1042 | |
530 | if (!$_[0]) { |
1043 | unless ($_[0]) { |
531 | aioreq_pri $pri; |
1044 | aioreq_pri $pri; |
532 | add $grp aio_unlink $src; |
1045 | add $grp aio_unlink $src; |
533 | } |
1046 | } |
534 | }; |
1047 | }; |
535 | } else { |
1048 | } else { |
… | |
… | |
538 | }; |
1051 | }; |
539 | |
1052 | |
540 | $grp |
1053 | $grp |
541 | } |
1054 | } |
542 | |
1055 | |
543 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
1056 | =item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
544 | |
1057 | |
545 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
1058 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
546 | efficiently separate the entries of directory C<$path> into two sets of |
1059 | efficiently separate the entries of directory C<$path> into two sets of |
547 | names, directories you can recurse into (directories), and ones you cannot |
1060 | names, directories you can recurse into (directories), and ones you cannot |
548 | recurse into (everything else, including symlinks to directories). |
1061 | recurse into (everything else, including symlinks to directories). |
549 | |
1062 | |
550 | C<aio_scandir> is a composite request that creates of many sub requests_ |
1063 | C<aio_scandir> is a composite request that generates many sub requests. |
551 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1064 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
552 | this function generates. If it is C<< <= 0 >>, then a suitable default |
1065 | this function generates. If it is C<< <= 0 >>, then a suitable default |
553 | will be chosen (currently 4). |
1066 | will be chosen (currently 4). |
554 | |
1067 | |
555 | On error, the callback is called without arguments, otherwise it receives |
1068 | On error, the callback is called without arguments, otherwise it receives |
… | |
… | |
565 | |
1078 | |
566 | Implementation notes. |
1079 | Implementation notes. |
567 | |
1080 | |
568 | The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can. |
1081 | The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can. |
569 | |
1082 | |
|
|
1083 | If readdir returns file type information, then this is used directly to |
|
|
1084 | find directories. |
|
|
1085 | |
570 | After reading the directory, the modification time, size etc. of the |
1086 | Otherwise, after reading the directory, the modification time, size etc. |
571 | directory before and after the readdir is checked, and if they match (and |
1087 | of the directory before and after the readdir is checked, and if they |
572 | isn't the current time), the link count will be used to decide how many |
1088 | match (and isn't the current time), the link count will be used to decide |
573 | entries are directories (if >= 2). Otherwise, no knowledge of the number |
1089 | how many entries are directories (if >= 2). Otherwise, no knowledge of the |
574 | of subdirectories will be assumed. |
1090 | number of subdirectories will be assumed. |
575 | |
1091 | |
576 | Then entries will be sorted into likely directories (everything without |
1092 | Then entries will be sorted into likely directories a non-initial dot |
577 | a non-initial dot currently) and likely non-directories (everything |
1093 | currently) and likely non-directories (see C<aio_readdirx>). Then every |
578 | else). Then every entry plus an appended C</.> will be C<stat>'ed, |
1094 | entry plus an appended C</.> will be C<stat>'ed, likely directories first, |
579 | likely directories first. If that succeeds, it assumes that the entry |
1095 | in order of their inode numbers. If that succeeds, it assumes that the |
580 | is a directory or a symlink to directory (which will be checked |
1096 | entry is a directory or a symlink to directory (which will be checked |
581 | seperately). This is often faster than stat'ing the entry itself because |
1097 | separately). This is often faster than stat'ing the entry itself because |
582 | filesystems might detect the type of the entry without reading the inode |
1098 | filesystems might detect the type of the entry without reading the inode |
583 | data (e.g. ext2fs filetype feature). |
1099 | data (e.g. ext2fs filetype feature), even on systems that cannot return |
|
|
1100 | the filetype information on readdir. |
584 | |
1101 | |
585 | If the known number of directories (link count - 2) has been reached, the |
1102 | If the known number of directories (link count - 2) has been reached, the |
586 | rest of the entries is assumed to be non-directories. |
1103 | rest of the entries is assumed to be non-directories. |
587 | |
1104 | |
588 | This only works with certainty on POSIX (= UNIX) filesystems, which |
1105 | This only works with certainty on POSIX (= UNIX) filesystems, which |
… | |
… | |
592 | as those tend to return 0 or 1 as link counts, which disables the |
1109 | as those tend to return 0 or 1 as link counts, which disables the |
593 | directory counting heuristic. |
1110 | directory counting heuristic. |
594 | |
1111 | |
595 | =cut |
1112 | =cut |
596 | |
1113 | |
597 | sub aio_scandir($$$) { |
1114 | sub aio_scandir($$;$) { |
598 | my ($path, $maxreq, $cb) = @_; |
1115 | my ($path, $maxreq, $cb) = @_; |
599 | |
1116 | |
600 | my $pri = aioreq_pri; |
1117 | my $pri = aioreq_pri; |
601 | |
1118 | |
602 | my $grp = aio_group $cb; |
1119 | my $grp = aio_group $cb; |
603 | |
1120 | |
604 | $maxreq = 4 if $maxreq <= 0; |
1121 | $maxreq = 4 if $maxreq <= 0; |
605 | |
1122 | |
606 | # stat once |
1123 | # get a wd object |
607 | aioreq_pri $pri; |
1124 | aioreq_pri $pri; |
608 | add $grp aio_stat $path, sub { |
1125 | add $grp aio_wd $path, sub { |
|
|
1126 | $_[0] |
609 | return $grp->result () if $_[0]; |
1127 | or return $grp->result (); |
610 | my $now = time; |
|
|
611 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
612 | |
1128 | |
613 | # read the directory entries |
1129 | my $wd = [shift, "."]; |
|
|
1130 | |
|
|
1131 | # stat once |
614 | aioreq_pri $pri; |
1132 | aioreq_pri $pri; |
615 | add $grp aio_readdir $path, sub { |
1133 | add $grp aio_stat $wd, sub { |
616 | my $entries = shift |
|
|
617 | or return $grp->result (); |
1134 | return $grp->result () if $_[0]; |
|
|
1135 | my $now = time; |
|
|
1136 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
1137 | my $rdxflags = READDIR_DIRS_FIRST; |
618 | |
1138 | |
619 | # stat the dir another time |
1139 | if ((stat _)[3] < 2) { |
|
|
1140 | # at least one non-POSIX filesystem exists |
|
|
1141 | # that returns useful DT_type values: btrfs, |
|
|
1142 | # so optimise for this here by requesting dents |
|
|
1143 | $rdxflags |= READDIR_DENTS; |
|
|
1144 | } |
|
|
1145 | |
|
|
1146 | # read the directory entries |
620 | aioreq_pri $pri; |
1147 | aioreq_pri $pri; |
621 | add $grp aio_stat $path, sub { |
1148 | add $grp aio_readdirx $wd, $rdxflags, sub { |
622 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
1149 | my ($entries, $flags) = @_ |
|
|
1150 | or return $grp->result (); |
623 | |
1151 | |
|
|
1152 | if ($rdxflags & READDIR_DENTS) { |
|
|
1153 | # if we requested type values, see if we can use them directly. |
|
|
1154 | |
|
|
1155 | # if there were any DT_UNKNOWN entries then we assume we |
|
|
1156 | # don't know. alternatively, we could assume that if we get |
|
|
1157 | # one DT_DIR, then all directories are indeed marked with |
|
|
1158 | # DT_DIR, but this seems not required for btrfs, and this |
|
|
1159 | # is basically the "btrfs can't get it's act together" code |
|
|
1160 | # branch. |
|
|
1161 | unless ($flags & READDIR_FOUND_UNKNOWN) { |
|
|
1162 | # now we have valid DT_ information for all entries, |
|
|
1163 | # so use it as an optimisation without further stat's. |
|
|
1164 | # they must also all be at the beginning of @$entries |
|
|
1165 | # by now. |
|
|
1166 | |
624 | my $ndirs; |
1167 | my $dirs; |
625 | |
1168 | |
626 | # take the slow route if anything looks fishy |
|
|
627 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
|
|
628 | $ndirs = -1; |
|
|
629 | } else { |
|
|
630 | # if nlink == 2, we are finished |
|
|
631 | # on non-posix-fs's, we rely on nlink < 2 |
|
|
632 | $ndirs = (stat _)[3] - 2 |
|
|
633 | or return $grp->result ([], $entries); |
|
|
634 | } |
|
|
635 | |
|
|
636 | # sort into likely dirs and likely nondirs |
|
|
637 | # dirs == files without ".", short entries first |
|
|
638 | $entries = [map $_->[0], |
|
|
639 | sort { $b->[1] cmp $a->[1] } |
|
|
640 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
|
|
641 | @$entries]; |
|
|
642 | |
|
|
643 | my (@dirs, @nondirs); |
|
|
644 | |
|
|
645 | my $statgrp = add $grp aio_group sub { |
|
|
646 | $grp->result (\@dirs, \@nondirs); |
|
|
647 | }; |
|
|
648 | |
|
|
649 | limit $statgrp $maxreq; |
|
|
650 | feed $statgrp sub { |
|
|
651 | return unless @$entries; |
|
|
652 | my $entry = pop @$entries; |
|
|
653 | |
|
|
654 | aioreq_pri $pri; |
|
|
655 | add $statgrp aio_stat "$path/$entry/.", sub { |
|
|
656 | if ($_[0] < 0) { |
1169 | if (@$entries) { |
657 | push @nondirs, $entry; |
1170 | for (0 .. $#$entries) { |
658 | } else { |
1171 | if ($entries->[$_][1] != DT_DIR) { |
659 | # need to check for real directory |
1172 | # splice out directories |
660 | aioreq_pri $pri; |
1173 | $dirs = [splice @$entries, 0, $_]; |
661 | add $statgrp aio_lstat "$path/$entry", sub { |
|
|
662 | if (-d _) { |
|
|
663 | push @dirs, $entry; |
|
|
664 | |
|
|
665 | unless (--$ndirs) { |
|
|
666 | push @nondirs, @$entries; |
|
|
667 | feed $statgrp; |
|
|
668 | } |
1174 | last; |
669 | } else { |
|
|
670 | push @nondirs, $entry; |
|
|
671 | } |
1175 | } |
672 | } |
1176 | } |
|
|
1177 | |
|
|
1178 | # if we didn't find any non-dir, then all entries are dirs |
|
|
1179 | unless ($dirs) { |
|
|
1180 | ($dirs, $entries) = ($entries, []); |
|
|
1181 | } |
|
|
1182 | } else { |
|
|
1183 | # directory is empty, so there are no sbdirs |
|
|
1184 | $dirs = []; |
673 | } |
1185 | } |
|
|
1186 | |
|
|
1187 | # either splice'd the directories out or the dir was empty. |
|
|
1188 | # convert dents to filenames |
|
|
1189 | $_ = $_->[0] for @$dirs; |
|
|
1190 | $_ = $_->[0] for @$entries; |
|
|
1191 | |
|
|
1192 | return $grp->result ($dirs, $entries); |
|
|
1193 | } |
|
|
1194 | |
|
|
1195 | # cannot use, so return to our old ways |
|
|
1196 | # by pretending we only scanned for names. |
|
|
1197 | $_ = $_->[0] for @$entries; |
|
|
1198 | } |
|
|
1199 | |
|
|
1200 | # stat the dir another time |
|
|
1201 | aioreq_pri $pri; |
|
|
1202 | add $grp aio_stat $wd, sub { |
|
|
1203 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
|
|
1204 | |
|
|
1205 | my $ndirs; |
|
|
1206 | |
|
|
1207 | # take the slow route if anything looks fishy |
|
|
1208 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
|
|
1209 | $ndirs = -1; |
|
|
1210 | } else { |
|
|
1211 | # if nlink == 2, we are finished |
|
|
1212 | # for non-posix-fs's, we rely on nlink < 2 |
|
|
1213 | $ndirs = (stat _)[3] - 2 |
|
|
1214 | or return $grp->result ([], $entries); |
|
|
1215 | } |
|
|
1216 | |
|
|
1217 | my (@dirs, @nondirs); |
|
|
1218 | |
|
|
1219 | my $statgrp = add $grp aio_group sub { |
|
|
1220 | $grp->result (\@dirs, \@nondirs); |
|
|
1221 | }; |
|
|
1222 | |
|
|
1223 | limit $statgrp $maxreq; |
|
|
1224 | feed $statgrp sub { |
|
|
1225 | return unless @$entries; |
|
|
1226 | my $entry = shift @$entries; |
|
|
1227 | |
|
|
1228 | aioreq_pri $pri; |
|
|
1229 | $wd->[1] = "$entry/."; |
|
|
1230 | add $statgrp aio_stat $wd, sub { |
|
|
1231 | if ($_[0] < 0) { |
|
|
1232 | push @nondirs, $entry; |
|
|
1233 | } else { |
|
|
1234 | # need to check for real directory |
|
|
1235 | aioreq_pri $pri; |
|
|
1236 | $wd->[1] = $entry; |
|
|
1237 | add $statgrp aio_lstat $wd, sub { |
|
|
1238 | if (-d _) { |
|
|
1239 | push @dirs, $entry; |
|
|
1240 | |
|
|
1241 | unless (--$ndirs) { |
|
|
1242 | push @nondirs, @$entries; |
|
|
1243 | feed $statgrp; |
|
|
1244 | } |
|
|
1245 | } else { |
|
|
1246 | push @nondirs, $entry; |
|
|
1247 | } |
|
|
1248 | } |
|
|
1249 | } |
|
|
1250 | }; |
674 | }; |
1251 | }; |
675 | }; |
1252 | }; |
676 | }; |
1253 | }; |
677 | }; |
1254 | }; |
678 | }; |
1255 | }; |
679 | |
1256 | |
680 | $grp |
1257 | $grp |
681 | } |
1258 | } |
682 | |
1259 | |
|
|
1260 | =item aio_rmtree $pathname, $callback->($status) |
|
|
1261 | |
|
|
1262 | Delete a directory tree starting (and including) C<$path>, return the |
|
|
1263 | status of the final C<rmdir> only. This is a composite request that |
|
|
1264 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
|
|
1265 | everything else. |
|
|
1266 | |
|
|
1267 | =cut |
|
|
1268 | |
|
|
1269 | sub aio_rmtree; |
|
|
1270 | sub aio_rmtree($;$) { |
|
|
1271 | my ($path, $cb) = @_; |
|
|
1272 | |
|
|
1273 | my $pri = aioreq_pri; |
|
|
1274 | my $grp = aio_group $cb; |
|
|
1275 | |
|
|
1276 | aioreq_pri $pri; |
|
|
1277 | add $grp aio_scandir $path, 0, sub { |
|
|
1278 | my ($dirs, $nondirs) = @_; |
|
|
1279 | |
|
|
1280 | my $dirgrp = aio_group sub { |
|
|
1281 | add $grp aio_rmdir $path, sub { |
|
|
1282 | $grp->result ($_[0]); |
|
|
1283 | }; |
|
|
1284 | }; |
|
|
1285 | |
|
|
1286 | (aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs; |
|
|
1287 | (aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs; |
|
|
1288 | |
|
|
1289 | add $grp $dirgrp; |
|
|
1290 | }; |
|
|
1291 | |
|
|
1292 | $grp |
|
|
1293 | } |
|
|
1294 | |
|
|
1295 | =item aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
1296 | |
|
|
1297 | =item aio_ioctl $fh, $request, $buf, $callback->($status) |
|
|
1298 | |
|
|
1299 | These work just like the C<fcntl> and C<ioctl> built-in functions, except |
|
|
1300 | they execute asynchronously and pass the return value to the callback. |
|
|
1301 | |
|
|
1302 | Both calls can be used for a lot of things, some of which make more sense |
|
|
1303 | to run asynchronously in their own thread, while some others make less |
|
|
1304 | sense. For example, calls that block waiting for external events, such |
|
|
1305 | as locking, will also lock down an I/O thread while it is waiting, which |
|
|
1306 | can deadlock the whole I/O system. At the same time, there might be no |
|
|
1307 | alternative to using a thread to wait. |
|
|
1308 | |
|
|
1309 | So in general, you should only use these calls for things that do |
|
|
1310 | (filesystem) I/O, not for things that wait for other events (network, |
|
|
1311 | other processes), although if you are careful and know what you are doing, |
|
|
1312 | you still can. |
|
|
1313 | |
|
|
1314 | The following constants are available and can be used for normal C<ioctl> |
|
|
1315 | and C<fcntl> as well (missing ones are, as usual C<0>): |
|
|
1316 | |
|
|
1317 | C<F_DUPFD_CLOEXEC>, |
|
|
1318 | |
|
|
1319 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
|
|
1320 | |
|
|
1321 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
|
|
1322 | |
|
|
1323 | C<F_ADD_SEALS>, C<F_GET_SEALS>, C<F_SEAL_SEAL>, C<F_SEAL_SHRINK>, C<F_SEAL_GROW> and |
|
|
1324 | C<F_SEAL_WRITE>. |
|
|
1325 | |
|
|
1326 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
|
|
1327 | C<FS_IOC_FIEMAP>. |
|
|
1328 | |
|
|
1329 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
|
|
1330 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
|
|
1331 | |
|
|
1332 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
|
|
1333 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
|
|
1334 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
|
|
1335 | C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>, |
|
|
1336 | C<FS_FL_USER_MODIFIABLE>. |
|
|
1337 | |
|
|
1338 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
|
|
1339 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
|
|
1340 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
|
|
1341 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
|
|
1342 | |
|
|
1343 | =item aio_sync $callback->($status) |
|
|
1344 | |
|
|
1345 | Asynchronously call sync and call the callback when finished. |
|
|
1346 | |
683 | =item aio_fsync $fh, $callback->($status) |
1347 | =item aio_fsync $fh, $callback->($status) |
684 | |
1348 | |
685 | Asynchronously call fsync on the given filehandle and call the callback |
1349 | Asynchronously call fsync on the given filehandle and call the callback |
686 | with the fsync result code. |
1350 | with the fsync result code. |
687 | |
1351 | |
… | |
… | |
690 | Asynchronously call fdatasync on the given filehandle and call the |
1354 | Asynchronously call fdatasync on the given filehandle and call the |
691 | callback with the fdatasync result code. |
1355 | callback with the fdatasync result code. |
692 | |
1356 | |
693 | If this call isn't available because your OS lacks it or it couldn't be |
1357 | If this call isn't available because your OS lacks it or it couldn't be |
694 | detected, it will be emulated by calling C<fsync> instead. |
1358 | detected, it will be emulated by calling C<fsync> instead. |
|
|
1359 | |
|
|
1360 | =item aio_syncfs $fh, $callback->($status) |
|
|
1361 | |
|
|
1362 | Asynchronously call the syncfs syscall to sync the filesystem associated |
|
|
1363 | to the given filehandle and call the callback with the syncfs result |
|
|
1364 | code. If syncfs is not available, calls sync(), but returns C<-1> and sets |
|
|
1365 | errno to C<ENOSYS> nevertheless. |
|
|
1366 | |
|
|
1367 | =item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
|
|
1368 | |
|
|
1369 | Sync the data portion of the file specified by C<$offset> and C<$length> |
|
|
1370 | to disk (but NOT the metadata), by calling the Linux-specific |
|
|
1371 | sync_file_range call. If sync_file_range is not available or it returns |
|
|
1372 | ENOSYS, then fdatasync or fsync is being substituted. |
|
|
1373 | |
|
|
1374 | C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>, |
|
|
1375 | C<IO::AIO::SYNC_FILE_RANGE_WRITE> and |
|
|
1376 | C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range |
|
|
1377 | manpage for details. |
|
|
1378 | |
|
|
1379 | =item aio_pathsync $pathname, $callback->($status) |
|
|
1380 | |
|
|
1381 | This request tries to open, fsync and close the given path. This is a |
|
|
1382 | composite request intended to sync directories after directory operations |
|
|
1383 | (E.g. rename). This might not work on all operating systems or have any |
|
|
1384 | specific effect, but usually it makes sure that directory changes get |
|
|
1385 | written to disc. It works for anything that can be opened for read-only, |
|
|
1386 | not just directories. |
|
|
1387 | |
|
|
1388 | Future versions of this function might fall back to other methods when |
|
|
1389 | C<fsync> on the directory fails (such as calling C<sync>). |
|
|
1390 | |
|
|
1391 | Passes C<0> when everything went ok, and C<-1> on error. |
|
|
1392 | |
|
|
1393 | =cut |
|
|
1394 | |
|
|
1395 | sub aio_pathsync($;$) { |
|
|
1396 | my ($path, $cb) = @_; |
|
|
1397 | |
|
|
1398 | my $pri = aioreq_pri; |
|
|
1399 | my $grp = aio_group $cb; |
|
|
1400 | |
|
|
1401 | aioreq_pri $pri; |
|
|
1402 | add $grp aio_open $path, O_RDONLY, 0, sub { |
|
|
1403 | my ($fh) = @_; |
|
|
1404 | if ($fh) { |
|
|
1405 | aioreq_pri $pri; |
|
|
1406 | add $grp aio_fsync $fh, sub { |
|
|
1407 | $grp->result ($_[0]); |
|
|
1408 | |
|
|
1409 | aioreq_pri $pri; |
|
|
1410 | add $grp aio_close $fh; |
|
|
1411 | }; |
|
|
1412 | } else { |
|
|
1413 | $grp->result (-1); |
|
|
1414 | } |
|
|
1415 | }; |
|
|
1416 | |
|
|
1417 | $grp |
|
|
1418 | } |
|
|
1419 | |
|
|
1420 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
|
|
1421 | |
|
|
1422 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
|
|
1423 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
|
|
1424 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
|
|
1425 | scalar must only be modified in-place while an aio operation is pending on |
|
|
1426 | it). |
|
|
1427 | |
|
|
1428 | It calls the C<msync> function of your OS, if available, with the memory |
|
|
1429 | area starting at C<$offset> in the string and ending C<$length> bytes |
|
|
1430 | later. If C<$length> is negative, counts from the end, and if C<$length> |
|
|
1431 | is C<undef>, then it goes till the end of the string. The flags can be |
|
|
1432 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
|
|
1433 | C<IO::AIO::MS_INVALIDATE>. |
|
|
1434 | |
|
|
1435 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
|
|
1436 | |
|
|
1437 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
|
|
1438 | scalars. |
|
|
1439 | |
|
|
1440 | It touches (reads or writes) all memory pages in the specified |
|
|
1441 | range inside the scalar. All caveats and parameters are the same |
|
|
1442 | as for C<aio_msync>, above, except for flags, which must be either |
|
|
1443 | C<0> (which reads all pages and ensures they are instantiated) or |
|
|
1444 | C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and |
|
|
1445 | writing an octet from it, which dirties the page). |
|
|
1446 | |
|
|
1447 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
|
|
1448 | |
|
|
1449 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
|
|
1450 | scalars. |
|
|
1451 | |
|
|
1452 | It reads in all the pages of the underlying storage into memory (if any) |
|
|
1453 | and locks them, so they are not getting swapped/paged out or removed. |
|
|
1454 | |
|
|
1455 | If C<$length> is undefined, then the scalar will be locked till the end. |
|
|
1456 | |
|
|
1457 | On systems that do not implement C<mlock>, this function returns C<-1> |
|
|
1458 | and sets errno to C<ENOSYS>. |
|
|
1459 | |
|
|
1460 | Note that the corresponding C<munlock> is synchronous and is |
|
|
1461 | documented under L<MISCELLANEOUS FUNCTIONS>. |
|
|
1462 | |
|
|
1463 | Example: open a file, mmap and mlock it - both will be undone when |
|
|
1464 | C<$data> gets destroyed. |
|
|
1465 | |
|
|
1466 | open my $fh, "<", $path or die "$path: $!"; |
|
|
1467 | my $data; |
|
|
1468 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
|
|
1469 | aio_mlock $data; # mlock in background |
|
|
1470 | |
|
|
1471 | =item aio_mlockall $flags, $callback->($status) |
|
|
1472 | |
|
|
1473 | Calls the C<mlockall> function with the given C<$flags> (a |
|
|
1474 | combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and |
|
|
1475 | C<IO::AIO::MCL_ONFAULT>). |
|
|
1476 | |
|
|
1477 | On systems that do not implement C<mlockall>, this function returns C<-1> |
|
|
1478 | and sets errno to C<ENOSYS>. Similarly, flag combinations not supported |
|
|
1479 | by the system result in a return value of C<-1> with errno being set to |
|
|
1480 | C<EINVAL>. |
|
|
1481 | |
|
|
1482 | Note that the corresponding C<munlockall> is synchronous and is |
|
|
1483 | documented under L<MISCELLANEOUS FUNCTIONS>. |
|
|
1484 | |
|
|
1485 | Example: asynchronously lock all current and future pages into memory. |
|
|
1486 | |
|
|
1487 | aio_mlockall IO::AIO::MCL_FUTURE; |
|
|
1488 | |
|
|
1489 | =item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
|
|
1490 | |
|
|
1491 | Queries the extents of the given file (by calling the Linux C<FIEMAP> |
|
|
1492 | ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If |
|
|
1493 | the ioctl is not available on your OS, then this request will fail with |
|
|
1494 | C<ENOSYS>. |
|
|
1495 | |
|
|
1496 | C<$start> is the starting offset to query extents for, C<$length> is the |
|
|
1497 | size of the range to query - if it is C<undef>, then the whole file will |
|
|
1498 | be queried. |
|
|
1499 | |
|
|
1500 | C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or |
|
|
1501 | C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also |
|
|
1502 | exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query |
|
|
1503 | the data portion. |
|
|
1504 | |
|
|
1505 | C<$count> is the maximum number of extent records to return. If it is |
|
|
1506 | C<undef>, then IO::AIO queries all extents of the range. As a very special |
|
|
1507 | case, if it is C<0>, then the callback receives the number of extents |
|
|
1508 | instead of the extents themselves (which is unreliable, see below). |
|
|
1509 | |
|
|
1510 | If an error occurs, the callback receives no arguments. The special |
|
|
1511 | C<errno> value C<IO::AIO::EBADR> is available to test for flag errors. |
|
|
1512 | |
|
|
1513 | Otherwise, the callback receives an array reference with extent |
|
|
1514 | structures. Each extent structure is an array reference itself, with the |
|
|
1515 | following members: |
|
|
1516 | |
|
|
1517 | [$logical, $physical, $length, $flags] |
|
|
1518 | |
|
|
1519 | Flags is any combination of the following flag values (typically either C<0> |
|
|
1520 | or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)): |
|
|
1521 | |
|
|
1522 | C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>, |
|
|
1523 | C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>, |
|
|
1524 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
|
|
1525 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
|
|
1526 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
|
|
1527 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
|
|
1528 | |
|
|
1529 | At the time of this writing (Linux 3.2), this request is unreliable unless |
|
|
1530 | C<$count> is C<undef>, as the kernel has all sorts of bugs preventing |
|
|
1531 | it to return all extents of a range for files with a large number of |
|
|
1532 | extents. The code (only) works around all these issues if C<$count> is |
|
|
1533 | C<undef>. |
695 | |
1534 | |
696 | =item aio_group $callback->(...) |
1535 | =item aio_group $callback->(...) |
697 | |
1536 | |
698 | This is a very special aio request: Instead of doing something, it is a |
1537 | This is a very special aio request: Instead of doing something, it is a |
699 | container for other aio requests, which is useful if you want to bundle |
1538 | container for other aio requests, which is useful if you want to bundle |
… | |
… | |
737 | immense (it blocks a thread for a long time) so do not use this function |
1576 | immense (it blocks a thread for a long time) so do not use this function |
738 | except to put your application under artificial I/O pressure. |
1577 | except to put your application under artificial I/O pressure. |
739 | |
1578 | |
740 | =back |
1579 | =back |
741 | |
1580 | |
|
|
1581 | |
|
|
1582 | =head2 IO::AIO::WD - multiple working directories |
|
|
1583 | |
|
|
1584 | Your process only has one current working directory, which is used by all |
|
|
1585 | threads. This makes it hard to use relative paths (some other component |
|
|
1586 | could call C<chdir> at any time, and it is hard to control when the path |
|
|
1587 | will be used by IO::AIO). |
|
|
1588 | |
|
|
1589 | One solution for this is to always use absolute paths. This usually works, |
|
|
1590 | but can be quite slow (the kernel has to walk the whole path on every |
|
|
1591 | access), and can also be a hassle to implement. |
|
|
1592 | |
|
|
1593 | Newer POSIX systems have a number of functions (openat, fdopendir, |
|
|
1594 | futimensat and so on) that make it possible to specify working directories |
|
|
1595 | per operation. |
|
|
1596 | |
|
|
1597 | For portability, and because the clowns who "designed", or shall I write, |
|
|
1598 | perpetrated this new interface were obviously half-drunk, this abstraction |
|
|
1599 | cannot be perfect, though. |
|
|
1600 | |
|
|
1601 | IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD |
|
|
1602 | object. This object stores the canonicalised, absolute version of the |
|
|
1603 | path, and on systems that allow it, also a directory file descriptor. |
|
|
1604 | |
|
|
1605 | Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat> |
|
|
1606 | or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD |
|
|
1607 | object and a pathname instead (or the IO::AIO::WD object alone, which |
|
|
1608 | gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the |
|
|
1609 | IO::AIO::WD object is ignored, otherwise the pathname is resolved relative |
|
|
1610 | to that IO::AIO::WD object. |
|
|
1611 | |
|
|
1612 | For example, to get a wd object for F</etc> and then stat F<passwd> |
|
|
1613 | inside, you would write: |
|
|
1614 | |
|
|
1615 | aio_wd "/etc", sub { |
|
|
1616 | my $etcdir = shift; |
|
|
1617 | |
|
|
1618 | # although $etcdir can be undef on error, there is generally no reason |
|
|
1619 | # to check for errors here, as aio_stat will fail with ENOENT |
|
|
1620 | # when $etcdir is undef. |
|
|
1621 | |
|
|
1622 | aio_stat [$etcdir, "passwd"], sub { |
|
|
1623 | # yay |
|
|
1624 | }; |
|
|
1625 | }; |
|
|
1626 | |
|
|
1627 | The fact that C<aio_wd> is a request and not a normal function shows that |
|
|
1628 | creating an IO::AIO::WD object is itself a potentially blocking operation, |
|
|
1629 | which is why it is done asynchronously. |
|
|
1630 | |
|
|
1631 | To stat the directory obtained with C<aio_wd> above, one could write |
|
|
1632 | either of the following three request calls: |
|
|
1633 | |
|
|
1634 | aio_lstat "/etc" , sub { ... # pathname as normal string |
|
|
1635 | aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself) |
|
|
1636 | aio_lstat $wd , sub { ... # shorthand for the previous |
|
|
1637 | |
|
|
1638 | As with normal pathnames, IO::AIO keeps a copy of the working directory |
|
|
1639 | object and the pathname string, so you could write the following without |
|
|
1640 | causing any issues due to C<$path> getting reused: |
|
|
1641 | |
|
|
1642 | my $path = [$wd, undef]; |
|
|
1643 | |
|
|
1644 | for my $name (qw(abc def ghi)) { |
|
|
1645 | $path->[1] = $name; |
|
|
1646 | aio_stat $path, sub { |
|
|
1647 | # ... |
|
|
1648 | }; |
|
|
1649 | } |
|
|
1650 | |
|
|
1651 | There are some caveats: when directories get renamed (or deleted), the |
|
|
1652 | pathname string doesn't change, so will point to the new directory (or |
|
|
1653 | nowhere at all), while the directory fd, if available on the system, |
|
|
1654 | will still point to the original directory. Most functions accepting a |
|
|
1655 | pathname will use the directory fd on newer systems, and the string on |
|
|
1656 | older systems. Some functions (such as C<aio_realpath>) will always rely on |
|
|
1657 | the string form of the pathname. |
|
|
1658 | |
|
|
1659 | So this functionality is mainly useful to get some protection against |
|
|
1660 | C<chdir>, to easily get an absolute path out of a relative path for future |
|
|
1661 | reference, and to speed up doing many operations in the same directory |
|
|
1662 | (e.g. when stat'ing all files in a directory). |
|
|
1663 | |
|
|
1664 | The following functions implement this working directory abstraction: |
|
|
1665 | |
|
|
1666 | =over 4 |
|
|
1667 | |
|
|
1668 | =item aio_wd $pathname, $callback->($wd) |
|
|
1669 | |
|
|
1670 | Asynchonously canonicalise the given pathname and convert it to an |
|
|
1671 | IO::AIO::WD object representing it. If possible and supported on the |
|
|
1672 | system, also open a directory fd to speed up pathname resolution relative |
|
|
1673 | to this working directory. |
|
|
1674 | |
|
|
1675 | If something goes wrong, then C<undef> is passwd to the callback instead |
|
|
1676 | of a working directory object and C<$!> is set appropriately. Since |
|
|
1677 | passing C<undef> as working directory component of a pathname fails the |
|
|
1678 | request with C<ENOENT>, there is often no need for error checking in the |
|
|
1679 | C<aio_wd> callback, as future requests using the value will fail in the |
|
|
1680 | expected way. |
|
|
1681 | |
|
|
1682 | =item IO::AIO::CWD |
|
|
1683 | |
|
|
1684 | This is a compile time constant (object) that represents the process |
|
|
1685 | current working directory. |
|
|
1686 | |
|
|
1687 | Specifying this object as working directory object for a pathname is as if |
|
|
1688 | the pathname would be specified directly, without a directory object. For |
|
|
1689 | example, these calls are functionally identical: |
|
|
1690 | |
|
|
1691 | aio_stat "somefile", sub { ... }; |
|
|
1692 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
|
|
1693 | |
|
|
1694 | =back |
|
|
1695 | |
|
|
1696 | To recover the path associated with an IO::AIO::WD object, you can use |
|
|
1697 | C<aio_realpath>: |
|
|
1698 | |
|
|
1699 | aio_realpath $wd, sub { |
|
|
1700 | warn "path is $_[0]\n"; |
|
|
1701 | }; |
|
|
1702 | |
|
|
1703 | Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir> |
|
|
1704 | sometimes, fall back to using an absolue path. |
|
|
1705 | |
742 | =head2 IO::AIO::REQ CLASS |
1706 | =head2 IO::AIO::REQ CLASS |
743 | |
1707 | |
744 | All non-aggregate C<aio_*> functions return an object of this class when |
1708 | All non-aggregate C<aio_*> functions return an object of this class when |
745 | called in non-void context. |
1709 | called in non-void context. |
746 | |
1710 | |
… | |
… | |
749 | =item cancel $req |
1713 | =item cancel $req |
750 | |
1714 | |
751 | Cancels the request, if possible. Has the effect of skipping execution |
1715 | Cancels the request, if possible. Has the effect of skipping execution |
752 | when entering the B<execute> state and skipping calling the callback when |
1716 | when entering the B<execute> state and skipping calling the callback when |
753 | entering the the B<result> state, but will leave the request otherwise |
1717 | entering the the B<result> state, but will leave the request otherwise |
754 | untouched. That means that requests that currently execute will not be |
1718 | untouched (with the exception of readdir). That means that requests that |
755 | stopped and resources held by the request will not be freed prematurely. |
1719 | currently execute will not be stopped and resources held by the request |
|
|
1720 | will not be freed prematurely. |
756 | |
1721 | |
757 | =item cb $req $callback->(...) |
1722 | =item cb $req $callback->(...) |
758 | |
1723 | |
759 | Replace (or simply set) the callback registered to the request. |
1724 | Replace (or simply set) the callback registered to the request. |
760 | |
1725 | |
… | |
… | |
811 | Their lifetime, simplified, looks like this: when they are empty, they |
1776 | Their lifetime, simplified, looks like this: when they are empty, they |
812 | will finish very quickly. If they contain only requests that are in the |
1777 | will finish very quickly. If they contain only requests that are in the |
813 | C<done> state, they will also finish. Otherwise they will continue to |
1778 | C<done> state, they will also finish. Otherwise they will continue to |
814 | exist. |
1779 | exist. |
815 | |
1780 | |
816 | That means after creating a group you have some time to add requests. And |
1781 | That means after creating a group you have some time to add requests |
817 | in the callbacks of those requests, you can add further requests to the |
1782 | (precisely before the callback has been invoked, which is only done within |
818 | group. And only when all those requests have finished will the the group |
1783 | the C<poll_cb>). And in the callbacks of those requests, you can add |
819 | itself finish. |
1784 | further requests to the group. And only when all those requests have |
|
|
1785 | finished will the the group itself finish. |
820 | |
1786 | |
821 | =over 4 |
1787 | =over 4 |
822 | |
1788 | |
823 | =item add $grp ... |
1789 | =item add $grp ... |
824 | |
1790 | |
… | |
… | |
833 | =item $grp->cancel_subs |
1799 | =item $grp->cancel_subs |
834 | |
1800 | |
835 | Cancel all subrequests and clears any feeder, but not the group request |
1801 | Cancel all subrequests and clears any feeder, but not the group request |
836 | itself. Useful when you queued a lot of events but got a result early. |
1802 | itself. Useful when you queued a lot of events but got a result early. |
837 | |
1803 | |
|
|
1804 | The group request will finish normally (you cannot add requests to the |
|
|
1805 | group). |
|
|
1806 | |
838 | =item $grp->result (...) |
1807 | =item $grp->result (...) |
839 | |
1808 | |
840 | Set the result value(s) that will be passed to the group callback when all |
1809 | Set the result value(s) that will be passed to the group callback when all |
841 | subrequests have finished and set thre groups errno to the current value |
1810 | subrequests have finished and set the groups errno to the current value |
842 | of errno (just like calling C<errno> without an error number). By default, |
1811 | of errno (just like calling C<errno> without an error number). By default, |
843 | no argument will be passed and errno is zero. |
1812 | no argument will be passed and errno is zero. |
844 | |
1813 | |
845 | =item $grp->errno ([$errno]) |
1814 | =item $grp->errno ([$errno]) |
846 | |
1815 | |
… | |
… | |
857 | =item feed $grp $callback->($grp) |
1826 | =item feed $grp $callback->($grp) |
858 | |
1827 | |
859 | Sets a feeder/generator on this group: every group can have an attached |
1828 | Sets a feeder/generator on this group: every group can have an attached |
860 | generator that generates requests if idle. The idea behind this is that, |
1829 | generator that generates requests if idle. The idea behind this is that, |
861 | although you could just queue as many requests as you want in a group, |
1830 | although you could just queue as many requests as you want in a group, |
862 | this might starve other requests for a potentially long time. For |
1831 | this might starve other requests for a potentially long time. For example, |
863 | example, C<aio_scandir> might generate hundreds of thousands C<aio_stat> |
1832 | C<aio_scandir> might generate hundreds of thousands of C<aio_stat> |
864 | requests, delaying any later requests for a long time. |
1833 | requests, delaying any later requests for a long time. |
865 | |
1834 | |
866 | To avoid this, and allow incremental generation of requests, you can |
1835 | To avoid this, and allow incremental generation of requests, you can |
867 | instead a group and set a feeder on it that generates those requests. The |
1836 | instead a group and set a feeder on it that generates those requests. The |
868 | feed callback will be called whenever there are few enough (see C<limit>, |
1837 | feed callback will be called whenever there are few enough (see C<limit>, |
… | |
… | |
873 | not impose any limits). |
1842 | not impose any limits). |
874 | |
1843 | |
875 | If the feed does not queue more requests when called, it will be |
1844 | If the feed does not queue more requests when called, it will be |
876 | automatically removed from the group. |
1845 | automatically removed from the group. |
877 | |
1846 | |
878 | If the feed limit is C<0>, it will be set to C<2> automatically. |
1847 | If the feed limit is C<0> when this method is called, it will be set to |
|
|
1848 | C<2> automatically. |
879 | |
1849 | |
880 | Example: |
1850 | Example: |
881 | |
1851 | |
882 | # stat all files in @files, but only ever use four aio requests concurrently: |
1852 | # stat all files in @files, but only ever use four aio requests concurrently: |
883 | |
1853 | |
… | |
… | |
895 | Sets the feeder limit for the group: The feeder will be called whenever |
1865 | Sets the feeder limit for the group: The feeder will be called whenever |
896 | the group contains less than this many requests. |
1866 | the group contains less than this many requests. |
897 | |
1867 | |
898 | Setting the limit to C<0> will pause the feeding process. |
1868 | Setting the limit to C<0> will pause the feeding process. |
899 | |
1869 | |
|
|
1870 | The default value for the limit is C<0>, but note that setting a feeder |
|
|
1871 | automatically bumps it up to C<2>. |
|
|
1872 | |
900 | =back |
1873 | =back |
901 | |
1874 | |
|
|
1875 | |
902 | =head2 SUPPORT FUNCTIONS |
1876 | =head2 SUPPORT FUNCTIONS |
903 | |
1877 | |
904 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
1878 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
905 | |
1879 | |
906 | =over 4 |
1880 | =over 4 |
907 | |
1881 | |
908 | =item $fileno = IO::AIO::poll_fileno |
1882 | =item $fileno = IO::AIO::poll_fileno |
909 | |
1883 | |
910 | Return the I<request result pipe file descriptor>. This filehandle must be |
1884 | Return the I<request result pipe file descriptor>. This filehandle must be |
911 | polled for reading by some mechanism outside this module (e.g. Event or |
1885 | polled for reading by some mechanism outside this module (e.g. EV, Glib, |
912 | select, see below or the SYNOPSIS). If the pipe becomes readable you have |
1886 | select and so on, see below or the SYNOPSIS). If the pipe becomes readable |
913 | to call C<poll_cb> to check the results. |
1887 | you have to call C<poll_cb> to check the results. |
914 | |
1888 | |
915 | See C<poll_cb> for an example. |
1889 | See C<poll_cb> for an example. |
916 | |
1890 | |
917 | =item IO::AIO::poll_cb |
1891 | =item IO::AIO::poll_cb |
918 | |
1892 | |
919 | Process some outstanding events on the result pipe. You have to call this |
1893 | Process some requests that have reached the result phase (i.e. they have |
920 | regularly. Returns the number of events processed. Returns immediately |
1894 | been executed but the results are not yet reported). You have to call |
921 | when no events are outstanding. The amount of events processed depends on |
1895 | this "regularly" to finish outstanding requests. |
922 | the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
|
|
923 | |
1896 | |
|
|
1897 | Returns C<0> if all events could be processed (or there were no |
|
|
1898 | events to process), or C<-1> if it returned earlier for whatever |
|
|
1899 | reason. Returns immediately when no events are outstanding. The amount |
|
|
1900 | of events processed depends on the settings of C<IO::AIO::max_poll_req>, |
|
|
1901 | C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>. |
|
|
1902 | |
924 | If not all requests were processed for whatever reason, the filehandle |
1903 | If not all requests were processed for whatever reason, the poll file |
925 | will still be ready when C<poll_cb> returns. |
1904 | descriptor will still be ready when C<poll_cb> returns, so normally you |
|
|
1905 | don't have to do anything special to have it called later. |
|
|
1906 | |
|
|
1907 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
|
|
1908 | ready, it can be beneficial to call this function from loops which submit |
|
|
1909 | a lot of requests, to make sure the results get processed when they become |
|
|
1910 | available and not just when the loop is finished and the event loop takes |
|
|
1911 | over again. This function returns very fast when there are no outstanding |
|
|
1912 | requests. |
926 | |
1913 | |
927 | Example: Install an Event watcher that automatically calls |
1914 | Example: Install an Event watcher that automatically calls |
928 | IO::AIO::poll_cb with high priority: |
1915 | IO::AIO::poll_cb with high priority (more examples can be found in the |
|
|
1916 | SYNOPSIS section, at the top of this document): |
929 | |
1917 | |
930 | Event->io (fd => IO::AIO::poll_fileno, |
1918 | Event->io (fd => IO::AIO::poll_fileno, |
931 | poll => 'r', async => 1, |
1919 | poll => 'r', async => 1, |
932 | cb => \&IO::AIO::poll_cb); |
1920 | cb => \&IO::AIO::poll_cb); |
|
|
1921 | |
|
|
1922 | =item IO::AIO::poll_wait |
|
|
1923 | |
|
|
1924 | Wait until either at least one request is in the result phase or no |
|
|
1925 | requests are outstanding anymore. |
|
|
1926 | |
|
|
1927 | This is useful if you want to synchronously wait for some requests to |
|
|
1928 | become ready, without actually handling them. |
|
|
1929 | |
|
|
1930 | See C<nreqs> for an example. |
|
|
1931 | |
|
|
1932 | =item IO::AIO::poll |
|
|
1933 | |
|
|
1934 | Waits until some requests have been handled. |
|
|
1935 | |
|
|
1936 | Returns the number of requests processed, but is otherwise strictly |
|
|
1937 | equivalent to: |
|
|
1938 | |
|
|
1939 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1940 | |
|
|
1941 | =item IO::AIO::flush |
|
|
1942 | |
|
|
1943 | Wait till all outstanding AIO requests have been handled. |
|
|
1944 | |
|
|
1945 | Strictly equivalent to: |
|
|
1946 | |
|
|
1947 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1948 | while IO::AIO::nreqs; |
|
|
1949 | |
|
|
1950 | This function can be useful at program aborts, to make sure outstanding |
|
|
1951 | I/O has been done (C<IO::AIO> uses an C<END> block which already calls |
|
|
1952 | this function on normal exits), or when you are merely using C<IO::AIO> |
|
|
1953 | for its more advanced functions, rather than for async I/O, e.g.: |
|
|
1954 | |
|
|
1955 | my ($dirs, $nondirs); |
|
|
1956 | IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ }; |
|
|
1957 | IO::AIO::flush; |
|
|
1958 | # $dirs, $nondirs are now set |
933 | |
1959 | |
934 | =item IO::AIO::max_poll_reqs $nreqs |
1960 | =item IO::AIO::max_poll_reqs $nreqs |
935 | |
1961 | |
936 | =item IO::AIO::max_poll_time $seconds |
1962 | =item IO::AIO::max_poll_time $seconds |
937 | |
1963 | |
… | |
… | |
939 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
1965 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
940 | the maximum amount of time (default C<0>, meaning infinity) spent in |
1966 | the maximum amount of time (default C<0>, meaning infinity) spent in |
941 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
1967 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
942 | of time C<poll_cb> is allowed to use). |
1968 | of time C<poll_cb> is allowed to use). |
943 | |
1969 | |
|
|
1970 | Setting C<max_poll_time> to a non-zero value creates an overhead of one |
|
|
1971 | syscall per request processed, which is not normally a problem unless your |
|
|
1972 | callbacks are really really fast or your OS is really really slow (I am |
|
|
1973 | not mentioning Solaris here). Using C<max_poll_reqs> incurs no overhead. |
|
|
1974 | |
944 | Setting these is useful if you want to ensure some level of |
1975 | Setting these is useful if you want to ensure some level of |
945 | interactiveness when perl is not fast enough to process all requests in |
1976 | interactiveness when perl is not fast enough to process all requests in |
946 | time. |
1977 | time. |
947 | |
1978 | |
948 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
1979 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
949 | |
1980 | |
950 | Example: Install an Event watcher that automatically calls |
1981 | Example: Install an Event watcher that automatically calls |
951 | IO::AIO::poll_some with low priority, to ensure that other parts of the |
1982 | IO::AIO::poll_cb with low priority, to ensure that other parts of the |
952 | program get the CPU sometimes even under high AIO load. |
1983 | program get the CPU sometimes even under high AIO load. |
953 | |
1984 | |
954 | # try not to spend much more than 0.1s in poll_cb |
1985 | # try not to spend much more than 0.1s in poll_cb |
955 | IO::AIO::max_poll_time 0.1; |
1986 | IO::AIO::max_poll_time 0.1; |
956 | |
1987 | |
957 | # use a low priority so other tasks have priority |
1988 | # use a low priority so other tasks have priority |
958 | Event->io (fd => IO::AIO::poll_fileno, |
1989 | Event->io (fd => IO::AIO::poll_fileno, |
959 | poll => 'r', nice => 1, |
1990 | poll => 'r', nice => 1, |
960 | cb => &IO::AIO::poll_cb); |
1991 | cb => &IO::AIO::poll_cb); |
961 | |
1992 | |
962 | =item IO::AIO::poll_wait |
1993 | =back |
963 | |
1994 | |
964 | Wait till the result filehandle becomes ready for reading (simply does a |
|
|
965 | C<select> on the filehandle. This is useful if you want to synchronously |
|
|
966 | wait for some requests to finish). |
|
|
967 | |
|
|
968 | See C<nreqs> for an example. |
|
|
969 | |
|
|
970 | =item IO::AIO::poll |
|
|
971 | |
|
|
972 | Waits until some requests have been handled. |
|
|
973 | |
|
|
974 | Strictly equivalent to: |
|
|
975 | |
|
|
976 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
977 | if IO::AIO::nreqs; |
|
|
978 | |
|
|
979 | =item IO::AIO::flush |
|
|
980 | |
|
|
981 | Wait till all outstanding AIO requests have been handled. |
|
|
982 | |
|
|
983 | Strictly equivalent to: |
|
|
984 | |
|
|
985 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
986 | while IO::AIO::nreqs; |
|
|
987 | |
1995 | |
988 | =head3 CONTROLLING THE NUMBER OF THREADS |
1996 | =head3 CONTROLLING THE NUMBER OF THREADS |
|
|
1997 | |
|
|
1998 | =over |
989 | |
1999 | |
990 | =item IO::AIO::min_parallel $nthreads |
2000 | =item IO::AIO::min_parallel $nthreads |
991 | |
2001 | |
992 | Set the minimum number of AIO threads to C<$nthreads>. The current |
2002 | Set the minimum number of AIO threads to C<$nthreads>. The current |
993 | default is C<8>, which means eight asynchronous operations can execute |
2003 | default is C<8>, which means eight asynchronous operations can execute |
… | |
… | |
1021 | |
2031 | |
1022 | Under normal circumstances you don't need to call this function. |
2032 | Under normal circumstances you don't need to call this function. |
1023 | |
2033 | |
1024 | =item IO::AIO::max_idle $nthreads |
2034 | =item IO::AIO::max_idle $nthreads |
1025 | |
2035 | |
1026 | Limit the number of threads (default: 4) that are allowed to idle (i.e., |
2036 | Limit the number of threads (default: 4) that are allowed to idle |
1027 | threads that did not get a request to process within 10 seconds). That |
2037 | (i.e., threads that did not get a request to process within the idle |
1028 | means if a thread becomes idle while C<$nthreads> other threads are also |
2038 | timeout (default: 10 seconds). That means if a thread becomes idle while |
1029 | idle, it will free its resources and exit. |
2039 | C<$nthreads> other threads are also idle, it will free its resources and |
|
|
2040 | exit. |
1030 | |
2041 | |
1031 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
2042 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
1032 | to allow for extremely high load situations, but want to free resources |
2043 | to allow for extremely high load situations, but want to free resources |
1033 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
2044 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
1034 | |
2045 | |
1035 | The default is probably ok in most situations, especially if thread |
2046 | The default is probably ok in most situations, especially if thread |
1036 | creation is fast. If thread creation is very slow on your system you might |
2047 | creation is fast. If thread creation is very slow on your system you might |
1037 | want to use larger values. |
2048 | want to use larger values. |
1038 | |
2049 | |
|
|
2050 | =item IO::AIO::idle_timeout $seconds |
|
|
2051 | |
|
|
2052 | Sets the minimum idle timeout (default 10) after which worker threads are |
|
|
2053 | allowed to exit. SEe C<IO::AIO::max_idle>. |
|
|
2054 | |
1039 | =item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
2055 | =item IO::AIO::max_outstanding $maxreqs |
|
|
2056 | |
|
|
2057 | Sets the maximum number of outstanding requests to C<$nreqs>. If |
|
|
2058 | you do queue up more than this number of requests, the next call to |
|
|
2059 | C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as |
|
|
2060 | C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no |
|
|
2061 | longer exceeded. |
|
|
2062 | |
|
|
2063 | In other words, this setting does not enforce a queue limit, but can be |
|
|
2064 | used to make poll functions block if the limit is exceeded. |
1040 | |
2065 | |
1041 | This is a very bad function to use in interactive programs because it |
2066 | This is a very bad function to use in interactive programs because it |
1042 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
2067 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1043 | use an C<aio_group> together with a feed callback. |
2068 | use an C<aio_group> together with a feed callback. |
1044 | |
2069 | |
1045 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
2070 | Its main use is in scripts without an event loop - when you want to stat |
1046 | to queue up more than this number of requests, the next call to the |
2071 | a lot of files, you can write something like this: |
1047 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
|
|
1048 | function will block until the limit is no longer exceeded. |
|
|
1049 | |
2072 | |
1050 | The default value is very large, so there is no practical limit on the |
2073 | IO::AIO::max_outstanding 32; |
1051 | number of outstanding requests. |
|
|
1052 | |
2074 | |
1053 | You can still queue as many requests as you want. Therefore, |
2075 | for my $path (...) { |
1054 | C<max_oustsanding> is mainly useful in simple scripts (with low values) or |
2076 | aio_stat $path , ...; |
1055 | as a stop gap to shield against fatal memory overflow (with large values). |
2077 | IO::AIO::poll_cb; |
|
|
2078 | } |
|
|
2079 | |
|
|
2080 | IO::AIO::flush; |
|
|
2081 | |
|
|
2082 | The call to C<poll_cb> inside the loop will normally return instantly, but |
|
|
2083 | as soon as more thna C<32> reqeusts are in-flight, it will block until |
|
|
2084 | some requests have been handled. This keeps the loop from pushing a large |
|
|
2085 | number of C<aio_stat> requests onto the queue. |
|
|
2086 | |
|
|
2087 | The default value for C<max_outstanding> is very large, so there is no |
|
|
2088 | practical limit on the number of outstanding requests. |
|
|
2089 | |
|
|
2090 | =back |
|
|
2091 | |
1056 | |
2092 | |
1057 | =head3 STATISTICAL INFORMATION |
2093 | =head3 STATISTICAL INFORMATION |
|
|
2094 | |
|
|
2095 | =over |
1058 | |
2096 | |
1059 | =item IO::AIO::nreqs |
2097 | =item IO::AIO::nreqs |
1060 | |
2098 | |
1061 | Returns the number of requests currently in the ready, execute or pending |
2099 | Returns the number of requests currently in the ready, execute or pending |
1062 | states (i.e. for which their callback has not been invoked yet). |
2100 | states (i.e. for which their callback has not been invoked yet). |
… | |
… | |
1076 | Returns the number of requests currently in the pending state (executed, |
2114 | Returns the number of requests currently in the pending state (executed, |
1077 | but not yet processed by poll_cb). |
2115 | but not yet processed by poll_cb). |
1078 | |
2116 | |
1079 | =back |
2117 | =back |
1080 | |
2118 | |
|
|
2119 | |
|
|
2120 | =head3 SUBSECOND STAT TIME ACCESS |
|
|
2121 | |
|
|
2122 | Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can |
|
|
2123 | generally find access/modification and change times with subsecond time |
|
|
2124 | accuracy of the system supports it, but perl's built-in functions only |
|
|
2125 | return the integer part. |
|
|
2126 | |
|
|
2127 | The following functions return the timestamps of the most recent |
|
|
2128 | stat with subsecond precision on most systems and work both after |
|
|
2129 | C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return |
|
|
2130 | value is only meaningful after a successful C<stat>/C<lstat> call, or |
|
|
2131 | during/after a successful C<aio_stat>/C<aio_lstat> callback. |
|
|
2132 | |
|
|
2133 | This is similar to the L<Time::HiRes> C<stat> functions, but can return |
|
|
2134 | full resolution without rounding and work with standard perl C<stat>, |
|
|
2135 | alleviating the need to call the special C<Time::HiRes> functions, which |
|
|
2136 | do not act like their perl counterparts. |
|
|
2137 | |
|
|
2138 | On operating systems or file systems where subsecond time resolution is |
|
|
2139 | not supported or could not be detected, a fractional part of C<0> is |
|
|
2140 | returned, so it is always safe to call these functions. |
|
|
2141 | |
|
|
2142 | =over 4 |
|
|
2143 | |
|
|
2144 | =item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime |
|
|
2145 | |
|
|
2146 | Return the access, modication, change or birth time, respectively, |
|
|
2147 | including fractional part. Due to the limited precision of floating point, |
|
|
2148 | the accuracy on most platforms is only a bit better than milliseconds |
|
|
2149 | for times around now - see the I<nsec> function family, below, for full |
|
|
2150 | accuracy. |
|
|
2151 | |
|
|
2152 | File birth time is only available when the OS and perl support it (on |
|
|
2153 | FreeBSD and NetBSD at the time of this writing, although support is |
|
|
2154 | adaptive, so if your OS/perl gains support, IO::AIO can take advantage of |
|
|
2155 | it). On systems where it isn't available, C<0> is currently returned, but |
|
|
2156 | this might change to C<undef> in a future version. |
|
|
2157 | |
|
|
2158 | =item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime |
|
|
2159 | |
|
|
2160 | Returns access, modification, change and birth time all in one go, and |
|
|
2161 | maybe more times in the future version. |
|
|
2162 | |
|
|
2163 | =item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec |
|
|
2164 | |
|
|
2165 | Return the fractional access, modifcation, change or birth time, in nanoseconds, |
|
|
2166 | as an integer in the range C<0> to C<999999999>. |
|
|
2167 | |
|
|
2168 | Note that no accessors are provided for access, modification and |
|
|
2169 | change times - you need to get those from C<stat _> if required (C<int |
|
|
2170 | IO::AIO::st_atime> and so on will I<not> generally give you the correct |
|
|
2171 | value). |
|
|
2172 | |
|
|
2173 | =item $seconds = IO::AIO::st_btimesec |
|
|
2174 | |
|
|
2175 | The (integral) seconds part of the file birth time, if available. |
|
|
2176 | |
|
|
2177 | =item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec |
|
|
2178 | |
|
|
2179 | Like the functions above, but returns all four times in one go (and maybe |
|
|
2180 | more in future versions). |
|
|
2181 | |
|
|
2182 | =item $counter = IO::AIO::st_gen |
|
|
2183 | |
|
|
2184 | Returns the generation counter (in practice this is just a random number) |
|
|
2185 | of the file. This is only available on platforms which have this member in |
|
|
2186 | their C<struct stat> (most BSDs at the time of this writing) and generally |
|
|
2187 | only to the root usert. If unsupported, C<0> is returned, but this might |
|
|
2188 | change to C<undef> in a future version. |
|
|
2189 | |
|
|
2190 | =back |
|
|
2191 | |
|
|
2192 | Example: print the high resolution modification time of F</etc>, using |
|
|
2193 | C<stat>, and C<IO::AIO::aio_stat>. |
|
|
2194 | |
|
|
2195 | if (stat "/etc") { |
|
|
2196 | printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime; |
|
|
2197 | } |
|
|
2198 | |
|
|
2199 | IO::AIO::aio_stat "/etc", sub { |
|
|
2200 | $_[0] |
|
|
2201 | and return; |
|
|
2202 | |
|
|
2203 | printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec; |
|
|
2204 | }; |
|
|
2205 | |
|
|
2206 | IO::AIO::flush; |
|
|
2207 | |
|
|
2208 | Output of the awbove on my system, showing reduced and full accuracy: |
|
|
2209 | |
|
|
2210 | stat(/etc) mtime: 1534043702.020808 |
|
|
2211 | aio_stat(/etc) mtime: 1534043702.020807792 |
|
|
2212 | |
|
|
2213 | |
|
|
2214 | =head3 MISCELLANEOUS FUNCTIONS |
|
|
2215 | |
|
|
2216 | IO::AIO implements some functions that are useful when you want to use |
|
|
2217 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
2218 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
|
|
2219 | counterpart. |
|
|
2220 | |
|
|
2221 | =over 4 |
|
|
2222 | |
|
|
2223 | =item $numfd = IO::AIO::get_fdlimit |
|
|
2224 | |
|
|
2225 | Tries to find the current file descriptor limit and returns it, or |
|
|
2226 | C<undef> and sets C<$!> in case of an error. The limit is one larger than |
|
|
2227 | the highest valid file descriptor number. |
|
|
2228 | |
|
|
2229 | =item IO::AIO::min_fdlimit [$numfd] |
|
|
2230 | |
|
|
2231 | Try to increase the current file descriptor limit(s) to at least C<$numfd> |
|
|
2232 | by changing the soft or hard file descriptor resource limit. If C<$numfd> |
|
|
2233 | is missing, it will try to set a very high limit, although this is not |
|
|
2234 | recommended when you know the actual minimum that you require. |
|
|
2235 | |
|
|
2236 | If the limit cannot be raised enough, the function makes a best-effort |
|
|
2237 | attempt to increase the limit as much as possible, using various |
|
|
2238 | tricks, while still failing. You can query the resulting limit using |
|
|
2239 | C<IO::AIO::get_fdlimit>. |
|
|
2240 | |
|
|
2241 | If an error occurs, returns C<undef> and sets C<$!>, otherwise returns |
|
|
2242 | true. |
|
|
2243 | |
|
|
2244 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
|
|
2245 | |
|
|
2246 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
|
|
2247 | but is blocking (this makes most sense if you know the input data is |
|
|
2248 | likely cached already and the output filehandle is set to non-blocking |
|
|
2249 | operations). |
|
|
2250 | |
|
|
2251 | Returns the number of bytes copied, or C<-1> on error. |
|
|
2252 | |
|
|
2253 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
|
|
2254 | |
|
|
2255 | Simply calls the C<posix_fadvise> function (see its |
|
|
2256 | manpage for details). The following advice constants are |
|
|
2257 | available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
|
|
2258 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
|
|
2259 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
|
|
2260 | |
|
|
2261 | On systems that do not implement C<posix_fadvise>, this function returns |
|
|
2262 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
|
|
2263 | |
|
|
2264 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
|
|
2265 | |
|
|
2266 | Simply calls the C<posix_madvise> function (see its |
|
|
2267 | manpage for details). The following advice constants are |
|
|
2268 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
|
|
2269 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2270 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2271 | |
|
|
2272 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2273 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2274 | will be reduced to fit into the C<$scalar>. |
|
|
2275 | |
|
|
2276 | On systems that do not implement C<posix_madvise>, this function returns |
|
|
2277 | ENOSYS, otherwise the return value of C<posix_madvise>. |
|
|
2278 | |
|
|
2279 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
|
|
2280 | |
|
|
2281 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
|
|
2282 | $scalar (see its manpage for details). The following protect |
|
|
2283 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
|
|
2284 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
|
|
2285 | |
|
|
2286 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2287 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2288 | will be reduced to fit into the C<$scalar>. |
|
|
2289 | |
|
|
2290 | On systems that do not implement C<mprotect>, this function returns |
|
|
2291 | ENOSYS, otherwise the return value of C<mprotect>. |
|
|
2292 | |
|
|
2293 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
|
|
2294 | |
|
|
2295 | Memory-maps a file (or anonymous memory range) and attaches it to the |
|
|
2296 | given C<$scalar>, which will act like a string scalar. Returns true on |
|
|
2297 | success, and false otherwise. |
|
|
2298 | |
|
|
2299 | The scalar must exist, but its contents do not matter - this means you |
|
|
2300 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2301 | the scalar first. |
|
|
2302 | |
|
|
2303 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
|
|
2304 | which don't change the string length, and most read-only operations such |
|
|
2305 | as copying it or searching it with regexes and so on. |
|
|
2306 | |
|
|
2307 | Anything else is unsafe and will, at best, result in memory leaks. |
|
|
2308 | |
|
|
2309 | The memory map associated with the C<$scalar> is automatically removed |
|
|
2310 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
|
|
2311 | or C<IO::AIO::munmap> functions are called on it. |
|
|
2312 | |
|
|
2313 | This calls the C<mmap>(2) function internally. See your system's manual |
|
|
2314 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
|
|
2315 | |
|
|
2316 | The C<$length> must be larger than zero and smaller than the actual |
|
|
2317 | filesize. |
|
|
2318 | |
|
|
2319 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
|
|
2320 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
|
|
2321 | |
|
|
2322 | C<$flags> can be a combination of |
|
|
2323 | C<IO::AIO::MAP_SHARED> or |
|
|
2324 | C<IO::AIO::MAP_PRIVATE>, |
|
|
2325 | or a number of system-specific flags (when not available, the are C<0>): |
|
|
2326 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
|
|
2327 | C<IO::AIO::MAP_LOCKED>, |
|
|
2328 | C<IO::AIO::MAP_NORESERVE>, |
|
|
2329 | C<IO::AIO::MAP_POPULATE>, |
|
|
2330 | C<IO::AIO::MAP_NONBLOCK>, |
|
|
2331 | C<IO::AIO::MAP_FIXED>, |
|
|
2332 | C<IO::AIO::MAP_GROWSDOWN>, |
|
|
2333 | C<IO::AIO::MAP_32BIT>, |
|
|
2334 | C<IO::AIO::MAP_HUGETLB>, |
|
|
2335 | C<IO::AIO::MAP_STACK>, |
|
|
2336 | C<IO::AIO::MAP_FIXED_NOREPLACE>, |
|
|
2337 | C<IO::AIO::MAP_SHARED_VALIDATE>, |
|
|
2338 | C<IO::AIO::MAP_SYNC> or |
|
|
2339 | C<IO::AIO::MAP_UNINITIALIZED>. |
|
|
2340 | |
|
|
2341 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
|
|
2342 | |
|
|
2343 | C<$offset> is the offset from the start of the file - it generally must be |
|
|
2344 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
|
|
2345 | |
|
|
2346 | Example: |
|
|
2347 | |
|
|
2348 | use Digest::MD5; |
|
|
2349 | use IO::AIO; |
|
|
2350 | |
|
|
2351 | open my $fh, "<verybigfile" |
|
|
2352 | or die "$!"; |
|
|
2353 | |
|
|
2354 | IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh |
|
|
2355 | or die "verybigfile: $!"; |
|
|
2356 | |
|
|
2357 | my $fast_md5 = md5 $data; |
|
|
2358 | |
|
|
2359 | =item IO::AIO::munmap $scalar |
|
|
2360 | |
|
|
2361 | Removes a previous mmap and undefines the C<$scalar>. |
|
|
2362 | |
|
|
2363 | =item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0] |
|
|
2364 | |
|
|
2365 | Calls the Linux-specific mremap(2) system call. The C<$scalar> must have |
|
|
2366 | been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be |
|
|
2367 | C<0> or C<IO::AIO::MREMAP_MAYMOVE>. |
|
|
2368 | |
|
|
2369 | Returns true if successful, and false otherwise. If the underlying mmapped |
|
|
2370 | region has changed address, then the true value has the numerical value |
|
|
2371 | C<1>, otherwise it has the numerical value C<0>: |
|
|
2372 | |
|
|
2373 | my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE |
|
|
2374 | or die "mremap: $!"; |
|
|
2375 | |
|
|
2376 | if ($success*1) { |
|
|
2377 | warn "scalar has chanegd address in memory\n"; |
|
|
2378 | } |
|
|
2379 | |
|
|
2380 | C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently |
|
|
2381 | implemented, but not supported and might go away in a future version. |
|
|
2382 | |
|
|
2383 | On systems where this call is not supported or is not emulated, this call |
|
|
2384 | returns falls and sets C<$!> to C<ENOSYS>. |
|
|
2385 | |
|
|
2386 | =item IO::AIO::mlockall $flags |
|
|
2387 | |
|
|
2388 | Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>, |
|
|
2389 | but is blocking. |
|
|
2390 | |
|
|
2391 | =item IO::AIO::munlock $scalar, $offset = 0, $length = undef |
|
|
2392 | |
|
|
2393 | Calls the C<munlock> function, undoing the effects of a previous |
|
|
2394 | C<aio_mlock> call (see its description for details). |
|
|
2395 | |
|
|
2396 | =item IO::AIO::munlockall |
|
|
2397 | |
|
|
2398 | Calls the C<munlockall> function. |
|
|
2399 | |
|
|
2400 | On systems that do not implement C<munlockall>, this function returns |
|
|
2401 | ENOSYS, otherwise the return value of C<munlockall>. |
|
|
2402 | |
|
|
2403 | =item $fh = IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_maxlen, $flags |
|
|
2404 | |
|
|
2405 | Uses the GNU/Linux C<accept4(2)> syscall, if available, to accept a socket |
|
|
2406 | and return the new file handle on success, or sets C<$!> and returns |
|
|
2407 | C<undef> on error. |
|
|
2408 | |
|
|
2409 | The remote name of the new socket will be stored in C<$sockaddr>, which |
|
|
2410 | will be extended to allow for at least C<$sockaddr_maxlen> octets. If the |
|
|
2411 | socket name does not fit into C<$sockaddr_maxlen> octets, this is signaled |
|
|
2412 | by returning a longer string in C<$sockaddr>, which might or might not be |
|
|
2413 | truncated. |
|
|
2414 | |
|
|
2415 | To accept name-less sockets, use C<undef> for C<$sockaddr> and C<0> for |
|
|
2416 | C<$sockaddr_maxlen>. |
|
|
2417 | |
|
|
2418 | The main reasons to use this syscall rather than portable C<accept(2)> |
|
|
2419 | are that you can specify C<SOCK_NONBLOCK> and/or C<SOCK_CLOEXEC> |
|
|
2420 | flags and you can accept name-less sockets by specifying C<0> for |
|
|
2421 | C<$sockaddr_maxlen>, which is sadly not possible with perl's interface to |
|
|
2422 | C<accept>. |
|
|
2423 | |
|
|
2424 | =item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
|
|
2425 | |
|
|
2426 | Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or |
|
|
2427 | C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they |
|
|
2428 | should be the file offset. |
|
|
2429 | |
|
|
2430 | C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might |
|
|
2431 | silently corrupt the data in this case. |
|
|
2432 | |
|
|
2433 | The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>, |
|
|
2434 | C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and |
|
|
2435 | C<IO::AIO::SPLICE_F_GIFT>. |
|
|
2436 | |
|
|
2437 | See the C<splice(2)> manpage for details. |
|
|
2438 | |
|
|
2439 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
|
|
2440 | |
|
|
2441 | Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the |
|
|
2442 | description for C<IO::AIO::splice> above for details. |
|
|
2443 | |
|
|
2444 | =item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
|
|
2445 | |
|
|
2446 | Attempts to query or change the pipe buffer size. Obviously works only |
|
|
2447 | on pipes, and currently works only on GNU/Linux systems, and fails with |
|
|
2448 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
|
|
2449 | size on other systems, drop me a note. |
|
|
2450 | |
|
|
2451 | =item ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
|
|
2452 | |
|
|
2453 | This is a direct interface to the Linux L<pipe2(2)> system call. If |
|
|
2454 | C<$flags> is missing or C<0>, then this should be the same as a call to |
|
|
2455 | perl's built-in C<pipe> function and create a new pipe, and works on |
|
|
2456 | systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe |
|
|
2457 | (..., 4096, O_BINARY)>. |
|
|
2458 | |
|
|
2459 | If C<$flags> is non-zero, it tries to invoke the pipe2 system call with |
|
|
2460 | the given flags (Linux 2.6.27, glibc 2.9). |
|
|
2461 | |
|
|
2462 | On success, the read and write file handles are returned. |
|
|
2463 | |
|
|
2464 | On error, nothing will be returned. If the pipe2 syscall is missing and |
|
|
2465 | C<$flags> is non-zero, fails with C<ENOSYS>. |
|
|
2466 | |
|
|
2467 | Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the |
|
|
2468 | time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and |
|
|
2469 | C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. |
|
|
2470 | |
|
|
2471 | Example: create a pipe race-free w.r.t. threads and fork: |
|
|
2472 | |
|
|
2473 | my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC |
|
|
2474 | or die "pipe2: $!\n"; |
|
|
2475 | |
|
|
2476 | =item $fh = IO::AIO::memfd_create $pathname[, $flags] |
|
|
2477 | |
|
|
2478 | This is a direct interface to the Linux L<memfd_create(2)> system |
|
|
2479 | call. The (unhelpful) default for C<$flags> is C<0>, but your default |
|
|
2480 | should be C<IO::AIO::MFD_CLOEXEC>. |
|
|
2481 | |
|
|
2482 | On success, the new memfd filehandle is returned, otherwise returns |
|
|
2483 | C<undef>. If the memfd_create syscall is missing, fails with C<ENOSYS>. |
|
|
2484 | |
|
|
2485 | Please refer to L<memfd_create(2)> for more info on this call. |
|
|
2486 | |
|
|
2487 | The following C<$flags> values are available: C<IO::AIO::MFD_CLOEXEC>, |
|
|
2488 | C<IO::AIO::MFD_ALLOW_SEALING> and C<IO::AIO::MFD_HUGETLB>. |
|
|
2489 | |
|
|
2490 | Example: create a new memfd. |
|
|
2491 | |
|
|
2492 | my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC |
|
|
2493 | or die "memfd_create: $!\n"; |
|
|
2494 | |
|
|
2495 | =item $fh = IO::AIO::pidfd_open $pid[, $flags] |
|
|
2496 | |
|
|
2497 | This is an interface to the Linux L<pidfd_open(2)> system call. The |
|
|
2498 | default for C<$flags> is C<0>. |
|
|
2499 | |
|
|
2500 | On success, a new pidfd filehandle is returned (that is already set to |
|
|
2501 | close-on-exec), otherwise returns C<undef>. If the syscall is missing, |
|
|
2502 | fails with C<ENOSYS>. |
|
|
2503 | |
|
|
2504 | Example: open pid 6341 as pidfd. |
|
|
2505 | |
|
|
2506 | my $fh = IO::AIO::pidfd_open 6341 |
|
|
2507 | or die "pidfd_open: $!\n"; |
|
|
2508 | |
|
|
2509 | =item $status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[, $flags]] |
|
|
2510 | |
|
|
2511 | This is an interface to the Linux L<pidfd_send_signal> system call. The |
|
|
2512 | default for C<$siginfo> is C<undef> and the default for C<$flags> is C<0>. |
|
|
2513 | |
|
|
2514 | Returns the system call status. If the syscall is missing, fails with |
|
|
2515 | C<ENOSYS>. |
|
|
2516 | |
|
|
2517 | When specified, C<$siginfo> must be a reference to a hash with one or more |
|
|
2518 | of the following members: |
|
|
2519 | |
|
|
2520 | =over |
|
|
2521 | |
|
|
2522 | =item code - the C<si_code> member |
|
|
2523 | |
|
|
2524 | =item pid - the C<si_pid> member |
|
|
2525 | |
|
|
2526 | =item uid - the C<si_uid> member |
|
|
2527 | |
|
|
2528 | =item value_int - the C<si_value.sival_int> member |
|
|
2529 | |
|
|
2530 | =item value_ptr - the C<si_value.sival_ptr> member, specified as an integer |
|
|
2531 | |
|
|
2532 | =back |
|
|
2533 | |
|
|
2534 | Example: send a SIGKILL to the specified process. |
|
|
2535 | |
|
|
2536 | my $status = IO::AIO::pidfd_send_signal $pidfh, 9, undef |
|
|
2537 | and die "pidfd_send_signal: $!\n"; |
|
|
2538 | |
|
|
2539 | Example: send a SIGKILL to the specified process with extra data. |
|
|
2540 | |
|
|
2541 | my $status = IO::AIO::pidfd_send_signal $pidfh, 9, { code => -1, value_int => 7 } |
|
|
2542 | and die "pidfd_send_signal: $!\n"; |
|
|
2543 | |
|
|
2544 | =item $fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags] |
|
|
2545 | |
|
|
2546 | This is an interface to the Linux L<pidfd_getfd> system call. The default |
|
|
2547 | for C<$flags> is C<0>. |
|
|
2548 | |
|
|
2549 | On success, returns a dup'ed copy of the target file descriptor (specified |
|
|
2550 | as an integer) returned (that is already set to close-on-exec), otherwise |
|
|
2551 | returns C<undef>. If the syscall is missing, fails with C<ENOSYS>. |
|
|
2552 | |
|
|
2553 | Example: get a copy of standard error of another process and print soemthing to it. |
|
|
2554 | |
|
|
2555 | my $errfh = IO::AIO::pidfd_getfd $pidfh, 2 |
|
|
2556 | or die "pidfd_getfd: $!\n"; |
|
|
2557 | print $errfh "stderr\n"; |
|
|
2558 | |
|
|
2559 | =item $fh = IO::AIO::eventfd [$initval, [$flags]] |
|
|
2560 | |
|
|
2561 | This is a direct interface to the Linux L<eventfd(2)> system call. The |
|
|
2562 | (unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both. |
|
|
2563 | |
|
|
2564 | On success, the new eventfd filehandle is returned, otherwise returns |
|
|
2565 | C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>. |
|
|
2566 | |
|
|
2567 | Please refer to L<eventfd(2)> for more info on this call. |
|
|
2568 | |
|
|
2569 | The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>, |
|
|
2570 | C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30). |
|
|
2571 | |
|
|
2572 | Example: create a new eventfd filehandle: |
|
|
2573 | |
|
|
2574 | $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC |
|
|
2575 | or die "eventfd: $!\n"; |
|
|
2576 | |
|
|
2577 | =item $fh = IO::AIO::timerfd_create $clockid[, $flags] |
|
|
2578 | |
|
|
2579 | This is a direct interface to the Linux L<timerfd_create(2)> system |
|
|
2580 | call. The (unhelpful) default for C<$flags> is C<0>, but your default |
|
|
2581 | should be C<IO::AIO::TFD_CLOEXEC>. |
|
|
2582 | |
|
|
2583 | On success, the new timerfd filehandle is returned, otherwise returns |
|
|
2584 | C<undef>. If the timerfd_create syscall is missing, fails with C<ENOSYS>. |
|
|
2585 | |
|
|
2586 | Please refer to L<timerfd_create(2)> for more info on this call. |
|
|
2587 | |
|
|
2588 | The following C<$clockid> values are |
|
|
2589 | available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC> |
|
|
2590 | C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15) |
|
|
2591 | C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and |
|
|
2592 | C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11). |
|
|
2593 | |
|
|
2594 | The following C<$flags> values are available (Linux |
|
|
2595 | 2.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>. |
|
|
2596 | |
|
|
2597 | Example: create a new timerfd and set it to one-second repeated alarms, |
|
|
2598 | then wait for two alarms: |
|
|
2599 | |
|
|
2600 | my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC |
|
|
2601 | or die "timerfd_create: $!\n"; |
|
|
2602 | |
|
|
2603 | defined IO::AIO::timerfd_settime $fh, 0, 1, 1 |
|
|
2604 | or die "timerfd_settime: $!\n"; |
|
|
2605 | |
|
|
2606 | for (1..2) { |
|
|
2607 | 8 == sysread $fh, my $buf, 8 |
|
|
2608 | or die "timerfd read failure\n"; |
|
|
2609 | |
|
|
2610 | printf "number of expirations (likely 1): %d\n", |
|
|
2611 | unpack "Q", $buf; |
|
|
2612 | } |
|
|
2613 | |
|
|
2614 | =item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value |
|
|
2615 | |
|
|
2616 | This is a direct interface to the Linux L<timerfd_settime(2)> system |
|
|
2617 | call. Please refer to its manpage for more info on this call. |
|
|
2618 | |
|
|
2619 | The new itimerspec is specified using two (possibly fractional) second |
|
|
2620 | values, C<$new_interval> and C<$new_value>). |
|
|
2621 | |
|
|
2622 | On success, the current interval and value are returned (as per |
|
|
2623 | C<timerfd_gettime>). On failure, the empty list is returned. |
|
|
2624 | |
|
|
2625 | The following C<$flags> values are |
|
|
2626 | available: C<IO::AIO::TFD_TIMER_ABSTIME> and |
|
|
2627 | C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>. |
|
|
2628 | |
|
|
2629 | See C<IO::AIO::timerfd_create> for a full example. |
|
|
2630 | |
|
|
2631 | =item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
|
|
2632 | |
|
|
2633 | This is a direct interface to the Linux L<timerfd_gettime(2)> system |
|
|
2634 | call. Please refer to its manpage for more info on this call. |
|
|
2635 | |
|
|
2636 | On success, returns the current values of interval and value for the given |
|
|
2637 | timerfd (as potentially fractional second values). On failure, the empty |
|
|
2638 | list is returned. |
|
|
2639 | |
|
|
2640 | =back |
|
|
2641 | |
1081 | =cut |
2642 | =cut |
1082 | |
2643 | |
1083 | # support function to convert a fd into a perl filehandle |
|
|
1084 | sub _fd2fh { |
|
|
1085 | return undef if $_[0] < 0; |
|
|
1086 | |
|
|
1087 | # try to generate nice filehandles |
|
|
1088 | my $sym = "IO::AIO::fd#$_[0]"; |
|
|
1089 | local *$sym; |
|
|
1090 | |
|
|
1091 | open *$sym, "+<&=$_[0]" # usually works under any unix |
|
|
1092 | or open *$sym, "<&=$_[0]" # cygwin needs this |
|
|
1093 | or open *$sym, ">&=$_[0]" # or this |
|
|
1094 | or return undef; |
|
|
1095 | |
|
|
1096 | *$sym |
|
|
1097 | } |
|
|
1098 | |
|
|
1099 | min_parallel 8; |
2644 | min_parallel 8; |
1100 | |
2645 | |
1101 | END { |
2646 | END { flush } |
1102 | min_parallel 1; |
|
|
1103 | flush; |
|
|
1104 | }; |
|
|
1105 | |
2647 | |
1106 | 1; |
2648 | 1; |
1107 | |
2649 | |
|
|
2650 | =head1 EVENT LOOP INTEGRATION |
|
|
2651 | |
|
|
2652 | It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO |
|
|
2653 | automatically into many event loops: |
|
|
2654 | |
|
|
2655 | # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...) |
|
|
2656 | use AnyEvent::AIO; |
|
|
2657 | |
|
|
2658 | You can also integrate IO::AIO manually into many event loops, here are |
|
|
2659 | some examples of how to do this: |
|
|
2660 | |
|
|
2661 | # EV integration |
|
|
2662 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
|
|
2663 | |
|
|
2664 | # Event integration |
|
|
2665 | Event->io (fd => IO::AIO::poll_fileno, |
|
|
2666 | poll => 'r', |
|
|
2667 | cb => \&IO::AIO::poll_cb); |
|
|
2668 | |
|
|
2669 | # Glib/Gtk2 integration |
|
|
2670 | add_watch Glib::IO IO::AIO::poll_fileno, |
|
|
2671 | in => sub { IO::AIO::poll_cb; 1 }; |
|
|
2672 | |
|
|
2673 | # Tk integration |
|
|
2674 | Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "", |
|
|
2675 | readable => \&IO::AIO::poll_cb); |
|
|
2676 | |
|
|
2677 | # Danga::Socket integration |
|
|
2678 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
|
|
2679 | \&IO::AIO::poll_cb); |
|
|
2680 | |
1108 | =head2 FORK BEHAVIOUR |
2681 | =head2 FORK BEHAVIOUR |
1109 | |
2682 | |
1110 | This module should do "the right thing" when the process using it forks: |
2683 | Usage of pthreads in a program changes the semantics of fork |
|
|
2684 | considerably. Specifically, only async-safe functions can be called after |
|
|
2685 | fork. Perl doesn't know about this, so in general, you cannot call fork |
|
|
2686 | with defined behaviour in perl if pthreads are involved. IO::AIO uses |
|
|
2687 | pthreads, so this applies, but many other extensions and (for inexplicable |
|
|
2688 | reasons) perl itself often is linked against pthreads, so this limitation |
|
|
2689 | applies to quite a lot of perls. |
1111 | |
2690 | |
1112 | Before the fork, IO::AIO enters a quiescent state where no requests |
2691 | This module no longer tries to fight your OS, or POSIX. That means IO::AIO |
1113 | can be added in other threads and no results will be processed. After |
2692 | only works in the process that loaded it. Forking is fully supported, but |
1114 | the fork the parent simply leaves the quiescent state and continues |
2693 | using IO::AIO in the child is not. |
1115 | request/result processing, while the child frees the request/result queue |
|
|
1116 | (so that the requests started before the fork will only be handled in the |
|
|
1117 | parent). Threads will be started on demand until the limit set in the |
|
|
1118 | parent process has been reached again. |
|
|
1119 | |
2694 | |
1120 | In short: the parent will, after a short pause, continue as if fork had |
2695 | You might get around by not I<using> IO::AIO before (or after) |
1121 | not been called, while the child will act as if IO::AIO has not been used |
2696 | forking. You could also try to call the L<IO::AIO::reinit> function in the |
1122 | yet. |
2697 | child: |
|
|
2698 | |
|
|
2699 | =over 4 |
|
|
2700 | |
|
|
2701 | =item IO::AIO::reinit |
|
|
2702 | |
|
|
2703 | Abandons all current requests and I/O threads and simply reinitialises all |
|
|
2704 | data structures. This is not an operation supported by any standards, but |
|
|
2705 | happens to work on GNU/Linux and some newer BSD systems. |
|
|
2706 | |
|
|
2707 | The only reasonable use for this function is to call it after forking, if |
|
|
2708 | C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in |
|
|
2709 | the process will result in undefined behaviour. Calling it at any time |
|
|
2710 | will also result in any undefined (by POSIX) behaviour. |
|
|
2711 | |
|
|
2712 | =back |
|
|
2713 | |
|
|
2714 | =head2 LINUX-SPECIFIC CALLS |
|
|
2715 | |
|
|
2716 | When a call is documented as "linux-specific" then this means it |
|
|
2717 | originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the |
|
|
2718 | availability and compatibility of such calls regardless of the platform |
|
|
2719 | it is compiled on, so platforms such as FreeBSD which often implement |
|
|
2720 | these calls will work. When in doubt, call them and see if they fail wth |
|
|
2721 | C<ENOSYS>. |
1123 | |
2722 | |
1124 | =head2 MEMORY USAGE |
2723 | =head2 MEMORY USAGE |
1125 | |
2724 | |
1126 | Per-request usage: |
2725 | Per-request usage: |
1127 | |
2726 | |
… | |
… | |
1129 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
2728 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
1130 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
2729 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
1131 | scalars and other data passed into aio requests will also be locked and |
2730 | scalars and other data passed into aio requests will also be locked and |
1132 | will consume memory till the request has entered the done state. |
2731 | will consume memory till the request has entered the done state. |
1133 | |
2732 | |
1134 | This is now awfully much, so queuing lots of requests is not usually a |
2733 | This is not awfully much, so queuing lots of requests is not usually a |
1135 | problem. |
2734 | problem. |
1136 | |
2735 | |
1137 | Per-thread usage: |
2736 | Per-thread usage: |
1138 | |
2737 | |
1139 | In the execution phase, some aio requests require more memory for |
2738 | In the execution phase, some aio requests require more memory for |
1140 | temporary buffers, and each thread requires a stack and other data |
2739 | temporary buffers, and each thread requires a stack and other data |
1141 | structures (usually around 16k-128k, depending on the OS). |
2740 | structures (usually around 16k-128k, depending on the OS). |
1142 | |
2741 | |
1143 | =head1 KNOWN BUGS |
2742 | =head1 KNOWN BUGS |
1144 | |
2743 | |
1145 | Known bugs will be fixed in the next release. |
2744 | Known bugs will be fixed in the next release :) |
|
|
2745 | |
|
|
2746 | =head1 KNOWN ISSUES |
|
|
2747 | |
|
|
2748 | Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap> |
|
|
2749 | or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as |
|
|
2750 | non-created hash slots or other scalars I didn't think of. It's best to |
|
|
2751 | avoid such and either use scalar variables or making sure that the scalar |
|
|
2752 | exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied). |
|
|
2753 | |
|
|
2754 | I am not sure anything can be done about this, so this is considered a |
|
|
2755 | known issue, rather than a bug. |
1146 | |
2756 | |
1147 | =head1 SEE ALSO |
2757 | =head1 SEE ALSO |
1148 | |
2758 | |
1149 | L<Coro::AIO>. |
2759 | L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a |
|
|
2760 | more natural syntax and L<IO::FDPass> for file descriptor passing. |
1150 | |
2761 | |
1151 | =head1 AUTHOR |
2762 | =head1 AUTHOR |
1152 | |
2763 | |
1153 | Marc Lehmann <schmorp@schmorp.de> |
2764 | Marc Lehmann <schmorp@schmorp.de> |
1154 | http://home.schmorp.de/ |
2765 | http://home.schmorp.de/ |