ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent/Handle.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.62 by root, Fri Jun 6 10:49:20 2008 UTC vs.
Revision 1.74 by root, Fri Jul 18 01:29:58 2008 UTC

14 14
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 16
17=cut 17=cut
18 18
19our $VERSION = 4.14; 19our $VERSION = 4.22;
20 20
21=head1 SYNOPSIS 21=head1 SYNOPSIS
22 22
23 use AnyEvent; 23 use AnyEvent;
24 use AnyEvent::Handle; 24 use AnyEvent::Handle;
75NOTE: The filehandle will be set to non-blocking (using 75NOTE: The filehandle will be set to non-blocking (using
76AnyEvent::Util::fh_nonblocking). 76AnyEvent::Util::fh_nonblocking).
77 77
78=item on_eof => $cb->($handle) 78=item on_eof => $cb->($handle)
79 79
80Set the callback to be called when an end-of-file condition is detcted, 80Set the callback to be called when an end-of-file condition is detected,
81i.e. in the case of a socket, when the other side has closed the 81i.e. in the case of a socket, when the other side has closed the
82connection cleanly. 82connection cleanly.
83 83
84While not mandatory, it is highly recommended to set an eof callback, 84While not mandatory, it is highly recommended to set an eof callback,
85otherwise you might end up with a closed socket while you are still 85otherwise you might end up with a closed socket while you are still
124This sets the callback that is called when the write buffer becomes empty 124This sets the callback that is called when the write buffer becomes empty
125(or when the callback is set and the buffer is empty already). 125(or when the callback is set and the buffer is empty already).
126 126
127To append to the write buffer, use the C<< ->push_write >> method. 127To append to the write buffer, use the C<< ->push_write >> method.
128 128
129This callback is useful when you don't want to put all of your write data
130into the queue at once, for example, when you want to write the contents
131of some file to the socket you might not want to read the whole file into
132memory and push it into the queue, but instead only read more data from
133the file when the write queue becomes empty.
134
129=item timeout => $fractional_seconds 135=item timeout => $fractional_seconds
130 136
131If non-zero, then this enables an "inactivity" timeout: whenever this many 137If non-zero, then this enables an "inactivity" timeout: whenever this many
132seconds pass without a successful read or write on the underlying file 138seconds pass without a successful read or write on the underlying file
133handle, the C<on_timeout> callback will be invoked (and if that one is 139handle, the C<on_timeout> callback will be invoked (and if that one is
156be configured to accept only so-and-so much data that it cannot act on 162be configured to accept only so-and-so much data that it cannot act on
157(for example, when expecting a line, an attacker could send an unlimited 163(for example, when expecting a line, an attacker could send an unlimited
158amount of data without a callback ever being called as long as the line 164amount of data without a callback ever being called as long as the line
159isn't finished). 165isn't finished).
160 166
167=item autocork => <boolean>
168
169When disabled (the default), then C<push_write> will try to immediately
170write the data to the handle if possible. This avoids having to register
171a write watcher and wait for the next event loop iteration, but can be
172inefficient if you write multiple small chunks (this disadvantage is
173usually avoided by your kernel's nagle algorithm, see C<low_delay>).
174
175When enabled, then writes will always be queued till the next event loop
176iteration. This is efficient when you do many small writes per iteration,
177but less efficient when you do a single write only.
178
179=item no_delay => <boolean>
180
181When doing small writes on sockets, your operating system kernel might
182wait a bit for more data before actually sending it out. This is called
183the Nagle algorithm, and usually it is beneficial.
184
185In some situations you want as low a delay as possible, which cna be
186accomplishd by setting this option to true.
187
188The default is your opertaing system's default behaviour, this option
189explicitly enables or disables it, if possible.
190
161=item read_size => <bytes> 191=item read_size => <bytes>
162 192
163The default read block size (the amount of bytes this module will try to read 193The default read block size (the amount of bytes this module will try to read
164during each (loop iteration). Default: C<8192>. 194during each (loop iteration). Default: C<8192>.
165 195
240 } 270 }
241 271
242 $self->{_activity} = AnyEvent->now; 272 $self->{_activity} = AnyEvent->now;
243 $self->_timeout; 273 $self->_timeout;
244 274
245 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 275 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
276 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
277
278 $self->start_read
279 if $self->{on_read};
246 280
247 $self 281 $self
248} 282}
249 283
250sub _shutdown { 284sub _shutdown {
309 343
310=cut 344=cut
311 345
312sub on_timeout { 346sub on_timeout {
313 $_[0]{on_timeout} = $_[1]; 347 $_[0]{on_timeout} = $_[1];
348}
349
350=item $handle->autocork ($boolean)
351
352Enables or disables the current autocork behaviour (see C<autocork>
353constructor argument).
354
355=cut
356
357=item $handle->no_delay ($boolean)
358
359Enables or disables the C<no_delay> setting (see constructor argument of
360the same name for details).
361
362=cut
363
364sub no_delay {
365 $_[0]{no_delay} = $_[1];
366
367 eval {
368 local $SIG{__DIE__};
369 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
370 };
314} 371}
315 372
316############################################################################# 373#############################################################################
317 374
318=item $handle->timeout ($seconds) 375=item $handle->timeout ($seconds)
433 $self->_error ($!, 1); 490 $self->_error ($!, 1);
434 } 491 }
435 }; 492 };
436 493
437 # try to write data immediately 494 # try to write data immediately
438 $cb->(); 495 $cb->() unless $self->{autocork};
439 496
440 # if still data left in wbuf, we need to poll 497 # if still data left in wbuf, we need to poll
441 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 498 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
442 if length $self->{wbuf}; 499 if length $self->{wbuf};
443 }; 500 };
500=cut 557=cut
501 558
502register_write_type packstring => sub { 559register_write_type packstring => sub {
503 my ($self, $format, $string) = @_; 560 my ($self, $format, $string) = @_;
504 561
505 pack "$format/a", $string 562 pack "$format/a*", $string
506}; 563};
507 564
508=item json => $array_or_hashref 565=item json => $array_or_hashref
509 566
510Encodes the given hash or array reference into a JSON object. Unless you 567Encodes the given hash or array reference into a JSON object. Unless you
544 601
545 $self->{json} ? $self->{json}->encode ($ref) 602 $self->{json} ? $self->{json}->encode ($ref)
546 : JSON::encode_json ($ref) 603 : JSON::encode_json ($ref)
547}; 604};
548 605
606=item storable => $reference
607
608Freezes the given reference using L<Storable> and writes it to the
609handle. Uses the C<nfreeze> format.
610
611=cut
612
613register_write_type storable => sub {
614 my ($self, $ref) = @_;
615
616 require Storable;
617
618 pack "w/a*", Storable::nfreeze ($ref)
619};
620
549=back 621=back
550 622
551=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 623=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
552 624
553This function (not method) lets you add your own types to C<push_write>. 625This function (not method) lets you add your own types to C<push_write>.
575ways, the "simple" way, using only C<on_read> and the "complex" way, using 647ways, the "simple" way, using only C<on_read> and the "complex" way, using
576a queue. 648a queue.
577 649
578In the simple case, you just install an C<on_read> callback and whenever 650In the simple case, you just install an C<on_read> callback and whenever
579new data arrives, it will be called. You can then remove some data (if 651new data arrives, it will be called. You can then remove some data (if
580enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 652enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
581or not. 653leave the data there if you want to accumulate more (e.g. when only a
654partial message has been received so far).
582 655
583In the more complex case, you want to queue multiple callbacks. In this 656In the more complex case, you want to queue multiple callbacks. In this
584case, AnyEvent::Handle will call the first queued callback each time new 657case, AnyEvent::Handle will call the first queued callback each time new
585data arrives (also the first time it is queued) and removes it when it has 658data arrives (also the first time it is queued) and removes it when it has
586done its job (see C<push_read>, below). 659done its job (see C<push_read>, below).
604 # handle xml 677 # handle xml
605 }); 678 });
606 }); 679 });
607 }); 680 });
608 681
609Example 2: Implement a client for a protocol that replies either with 682Example 2: Implement a client for a protocol that replies either with "OK"
610"OK" and another line or "ERROR" for one request, and 64 bytes for the 683and another line or "ERROR" for the first request that is sent, and 64
611second request. Due tot he availability of a full queue, we can just 684bytes for the second request. Due to the availability of a queue, we can
612pipeline sending both requests and manipulate the queue as necessary in 685just pipeline sending both requests and manipulate the queue as necessary
613the callbacks: 686in the callbacks.
614 687
615 # request one 688When the first callback is called and sees an "OK" response, it will
689C<unshift> another line-read. This line-read will be queued I<before> the
69064-byte chunk callback.
691
692 # request one, returns either "OK + extra line" or "ERROR"
616 $handle->push_write ("request 1\015\012"); 693 $handle->push_write ("request 1\015\012");
617 694
618 # we expect "ERROR" or "OK" as response, so push a line read 695 # we expect "ERROR" or "OK" as response, so push a line read
619 $handle->push_read (line => sub { 696 $handle->push_read (line => sub {
620 # if we got an "OK", we have to _prepend_ another line, 697 # if we got an "OK", we have to _prepend_ another line,
627 ... 704 ...
628 }); 705 });
629 } 706 }
630 }); 707 });
631 708
632 # request two 709 # request two, simply returns 64 octets
633 $handle->push_write ("request 2\015\012"); 710 $handle->push_write ("request 2\015\012");
634 711
635 # simply read 64 bytes, always 712 # simply read 64 bytes, always
636 $handle->push_read (chunk => 64, sub { 713 $handle->push_read (chunk => 64, sub {
637 my $response = $_[1]; 714 my $response = $_[1];
1045the C<json> write type description, above, for an actual example. 1122the C<json> write type description, above, for an actual example.
1046 1123
1047=cut 1124=cut
1048 1125
1049register_read_type json => sub { 1126register_read_type json => sub {
1050 my ($self, $cb, $accept, $reject, $skip) = @_; 1127 my ($self, $cb) = @_;
1051 1128
1052 require JSON; 1129 require JSON;
1053 1130
1054 my $data; 1131 my $data;
1055 my $rbuf = \$self->{rbuf}; 1132 my $rbuf = \$self->{rbuf};
1067 1 1144 1
1068 } else { 1145 } else {
1069 $self->{rbuf} = ""; 1146 $self->{rbuf} = "";
1070 () 1147 ()
1071 } 1148 }
1149 }
1150};
1151
1152=item storable => $cb->($handle, $ref)
1153
1154Deserialises a L<Storable> frozen representation as written by the
1155C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1156data).
1157
1158Raises C<EBADMSG> error if the data could not be decoded.
1159
1160=cut
1161
1162register_read_type storable => sub {
1163 my ($self, $cb) = @_;
1164
1165 require Storable;
1166
1167 sub {
1168 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1169 defined (my $len = eval { unpack "w", $_[0]->{rbuf} })
1170 or return;
1171
1172 # remove prefix
1173 substr $_[0]->{rbuf}, 0, (length pack "w", $len), "";
1174
1175 # read rest
1176 $_[0]->unshift_read (chunk => $len, sub {
1177 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1178 $cb->($_[0], $ref);
1179 } else {
1180 $self->_error (&Errno::EBADMSG);
1181 }
1182 });
1072 } 1183 }
1073}; 1184};
1074 1185
1075=back 1186=back
1076 1187

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines