[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent/Handle.pm

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.82 by root, Thu Aug 21 18:45:16 2008 UTC vs.
Revision 1.129 by root, Mon Jun 29 11:04:09 2009 UTC

…		…
14		14
15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16		16
17	=cut	17	=cut
18		18
19	our $VERSION = 4.232;	19	our $VERSION = 4.42;
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
…		…
27		27
28	my $handle =	28	my $handle =
29	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
30	fh => \*STDIN,	30	fh => \*STDIN,
31	on_eof => sub {	31	on_eof => sub {
32	$cv->broadcast;	32	$cv->send;
33	},	33	},
34	);	34	);
35		35
36	# send some request line	36	# send some request line
37	$handle->push_write ("getinfo\015\012");	37	$handle->push_write ("getinfo\015\012");
…		…
49		49
50	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
52	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
53		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
54	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
55	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
56	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
57		60
58	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
…		…
70		73
71	=item fh => $filehandle [MANDATORY]	74	=item fh => $filehandle [MANDATORY]
72		75
73	The filehandle this L<AnyEvent::Handle> object will operate on.	76	The filehandle this L<AnyEvent::Handle> object will operate on.
74		77
75	NOTE: The filehandle will be set to non-blocking (using	78	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
77		81
78	=item on_eof => $cb->($handle)	82	=item on_eof => $cb->($handle)
79		83
80	Set the callback to be called when an end-of-file condition is detected,	84	Set the callback to be called when an end-of-file condition is detected,
81	i.e. in the case of a socket, when the other side has closed the	85	i.e. in the case of a socket, when the other side has closed the
82	connection cleanly.	86	connection cleanly.
83		87
84	For sockets, this just means that the other side has stopped sending data,	88	For sockets, this just means that the other side has stopped sending data,
85	you can still try to write data, and, in fact, one can return from the eof	89	you can still try to write data, and, in fact, one can return from the EOF
86	callback and continue writing data, as only the read part has been shut	90	callback and continue writing data, as only the read part has been shut
87	down.	91	down.
88		92
89	While not mandatory, it is I<highly> recommended to set an eof callback,	93	While not mandatory, it is I<highly> recommended to set an EOF callback,
90	otherwise you might end up with a closed socket while you are still	94	otherwise you might end up with a closed socket while you are still
91	waiting for data.	95	waiting for data.
92		96
93	If an EOF condition has been detected but no C<on_eof> callback has been	97	If an EOF condition has been detected but no C<on_eof> callback has been
94	set, then a fatal error will be raised with C<$!> set to <0>.	98	set, then a fatal error will be raised with C<$!> set to <0>.
…		…
99	occured, such as not being able to resolve the hostname, failure to	103	occured, such as not being able to resolve the hostname, failure to
100	connect or a read error.	104	connect or a read error.
101		105
102	Some errors are fatal (which is indicated by C<$fatal> being true). On	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
103	fatal errors the handle object will be shut down and will not be usable	107	fatal errors the handle object will be shut down and will not be usable
104	(but you are free to look at the current C< ->rbuf >). Examples of fatal	108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
105	errors are an EOF condition with active (but unsatisifable) read watchers	109	errors are an EOF condition with active (but unsatisifable) read watchers
106	(C<EPIPE>) or I/O errors.	110	(C<EPIPE>) or I/O errors.
107		111
108	Non-fatal errors can be retried by simply returning, but it is recommended	112	Non-fatal errors can be retried by simply returning, but it is recommended
109	to simply ignore this parameter and instead abondon the handle object	113	to simply ignore this parameter and instead abondon the handle object
…		…
123	and no read request is in the queue (unlike read queue callbacks, this	127	and no read request is in the queue (unlike read queue callbacks, this
124	callback will only be called when at least one octet of data is in the	128	callback will only be called when at least one octet of data is in the
125	read buffer).	129	read buffer).
126		130
127	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	131	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
128	method or access the C<$handle->{rbuf}> member directly.	132	method or access the C<$handle->{rbuf}> member directly. Note that you
		133	must not enlarge or modify the read buffer, you can only remove data at
		134	the beginning from it.
129		135
130	When an EOF condition is detected then AnyEvent::Handle will first try to	136	When an EOF condition is detected then AnyEvent::Handle will first try to
131	feed all the remaining data to the queued callbacks and C<on_read> before	137	feed all the remaining data to the queued callbacks and C<on_read> before
132	calling the C<on_eof> callback. If no progress can be made, then a fatal	138	calling the C<on_eof> callback. If no progress can be made, then a fatal
133	error will be raised (with C<$!> set to C<EPIPE>).	139	error will be raised (with C<$!> set to C<EPIPE>).
…		…
148	=item timeout => $fractional_seconds	154	=item timeout => $fractional_seconds
149		155
150	If non-zero, then this enables an "inactivity" timeout: whenever this many	156	If non-zero, then this enables an "inactivity" timeout: whenever this many
151	seconds pass without a successful read or write on the underlying file	157	seconds pass without a successful read or write on the underlying file
152	handle, the C<on_timeout> callback will be invoked (and if that one is	158	handle, the C<on_timeout> callback will be invoked (and if that one is
153	missing, an C<ETIMEDOUT> error will be raised).	159	missing, a non-fatal C<ETIMEDOUT> error will be raised).
154		160
155	Note that timeout processing is also active when you currently do not have	161	Note that timeout processing is also active when you currently do not have
156	any outstanding read or write requests: If you plan to keep the connection	162	any outstanding read or write requests: If you plan to keep the connection
157	idle then you should disable the timout temporarily or ignore the timeout	163	idle then you should disable the timout temporarily or ignore the timeout
158	in the C<on_timeout> callback.	164	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		165	restart the timeout.
159		166
160	Zero (the default) disables this timeout.	167	Zero (the default) disables this timeout.
161		168
162	=item on_timeout => $cb->($handle)	169	=item on_timeout => $cb->($handle)
163		170
…		…
167		174
168	=item rbuf_max => <bytes>	175	=item rbuf_max => <bytes>
169		176
170	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	177	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
171	when the read buffer ever (strictly) exceeds this size. This is useful to	178	when the read buffer ever (strictly) exceeds this size. This is useful to
172	avoid denial-of-service attacks.	179	avoid some forms of denial-of-service attacks.
173		180
174	For example, a server accepting connections from untrusted sources should	181	For example, a server accepting connections from untrusted sources should
175	be configured to accept only so-and-so much data that it cannot act on	182	be configured to accept only so-and-so much data that it cannot act on
176	(for example, when expecting a line, an attacker could send an unlimited	183	(for example, when expecting a line, an attacker could send an unlimited
177	amount of data without a callback ever being called as long as the line	184	amount of data without a callback ever being called as long as the line
178	isn't finished).	185	isn't finished).
179		186
180	=item autocork => <boolean>	187	=item autocork => <boolean>
181		188
182	When disabled (the default), then C<push_write> will try to immediately	189	When disabled (the default), then C<push_write> will try to immediately
183	write the data to the handle if possible. This avoids having to register	190	write the data to the handle, if possible. This avoids having to register
184	a write watcher and wait for the next event loop iteration, but can be	191	a write watcher and wait for the next event loop iteration, but can
185	inefficient if you write multiple small chunks (this disadvantage is	192	be inefficient if you write multiple small chunks (on the wire, this
186	usually avoided by your kernel's nagle algorithm, see C<low_delay>).	193	disadvantage is usually avoided by your kernel's nagle algorithm, see
		194	C<no_delay>, but this option can save costly syscalls).
187		195
188	When enabled, then writes will always be queued till the next event loop	196	When enabled, then writes will always be queued till the next event loop
189	iteration. This is efficient when you do many small writes per iteration,	197	iteration. This is efficient when you do many small writes per iteration,
190	but less efficient when you do a single write only.	198	but less efficient when you do a single write only per iteration (or when
		199	the write buffer often is full). It also increases write latency.
191		200
192	=item no_delay => <boolean>	201	=item no_delay => <boolean>
193		202
194	When doing small writes on sockets, your operating system kernel might	203	When doing small writes on sockets, your operating system kernel might
195	wait a bit for more data before actually sending it out. This is called	204	wait a bit for more data before actually sending it out. This is called
196	the Nagle algorithm, and usually it is beneficial.	205	the Nagle algorithm, and usually it is beneficial.
197		206
198	In some situations you want as low a delay as possible, which cna be	207	In some situations you want as low a delay as possible, which can be
199	accomplishd by setting this option to true.	208	accomplishd by setting this option to a true value.
200		209
201	The default is your opertaing system's default behaviour, this option	210	The default is your opertaing system's default behaviour (most likely
202	explicitly enables or disables it, if possible.	211	enabled), this option explicitly enables or disables it, if possible.
203		212
204	=item read_size => <bytes>	213	=item read_size => <bytes>
205		214
206	The default read block size (the amount of bytes this module will try to read	215	The default read block size (the amount of bytes this module will
207	during each (loop iteration). Default: C<8192>.	216	try to read during each loop iteration, which affects memory
		217	requirements). Default: C<8192>.
208		218
209	=item low_water_mark => <bytes>	219	=item low_water_mark => <bytes>
210		220
211	Sets the amount of bytes (default: C<0>) that make up an "empty" write	221	Sets the amount of bytes (default: C<0>) that make up an "empty" write
212	buffer: If the write reaches this size or gets even samller it is	222	buffer: If the write reaches this size or gets even samller it is
213	considered empty.	223	considered empty.
214		224
		225	Sometimes it can be beneficial (for performance reasons) to add data to
		226	the write buffer before it is fully drained, but this is a rare case, as
		227	the operating system kernel usually buffers data as well, so the default
		228	is good in almost all cases.
		229
215	=item linger => <seconds>	230	=item linger => <seconds>
216		231
217	If non-zero (default: C<3600>), then the destructor of the	232	If non-zero (default: C<3600>), then the destructor of the
218	AnyEvent::Handle object will check wether there is still outstanding write	233	AnyEvent::Handle object will check whether there is still outstanding
219	data and will install a watcher that will write out this data. No errors	234	write data and will install a watcher that will write this data to the
220	will be reported (this mostly matches how the operating system treats	235	socket. No errors will be reported (this mostly matches how the operating
221	outstanding data at socket close time).	236	system treats outstanding data at socket close time).
222		237
223	This will not work for partial TLS data that could not yet been	238	This will not work for partial TLS data that could not be encoded
224	encoded. This data will be lost.	239	yet. This data will be lost. Calling the C<stoptls> method in time might
		240	help.
225		241
226	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object	242	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object
227		243
228	When this parameter is given, it enables TLS (SSL) mode, that means it	244	When this parameter is given, it enables TLS (SSL) mode, that means
229	will start making tls handshake and will transparently encrypt/decrypt	245	AnyEvent will start a TLS handshake as soon as the conenction has been
230	data.	246	established and will transparently encrypt/decrypt data afterwards.
231		247
232	TLS mode requires Net::SSLeay to be installed (it will be loaded	248	TLS mode requires Net::SSLeay to be installed (it will be loaded
233	automatically when you try to create a TLS handle).	249	automatically when you try to create a TLS handle): this module doesn't
		250	have a dependency on that module, so if your module requires it, you have
		251	to add the dependency yourself.
234		252
235	For the TLS server side, use C<accept>, and for the TLS client side of a	253	Unlike TCP, TLS has a server and client side: for the TLS server side, use
236	connection, use C<connect> mode.	254	C<accept>, and for the TLS client side of a connection, use C<connect>
		255	mode.
237		256
238	You can also provide your own TLS connection object, but you have	257	You can also provide your own TLS connection object, but you have
239	to make sure that you call either C<Net::SSLeay::set_connect_state>	258	to make sure that you call either C<Net::SSLeay::set_connect_state>
240	or C<Net::SSLeay::set_accept_state> on it before you pass it to	259	or C<Net::SSLeay::set_accept_state> on it before you pass it to
241	AnyEvent::Handle.	260	AnyEvent::Handle.
242		261
		262	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		263	passing in the wrong integer will lead to certain crash. This most often
		264	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		265	segmentation fault.
		266
243	See the C<starttls> method if you need to start TLS negotiation later.	267	See the C<< ->starttls >> method for when need to start TLS negotiation later.
244		268
245	=item tls_ctx => $ssl_ctx	269	=item tls_ctx => $ssl_ctx
246		270
247	Use the given Net::SSLeay::CTX object to create the new TLS connection	271	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
248	(unless a connection object was specified directly). If this parameter is	272	(unless a connection object was specified directly). If this parameter is
249	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	273	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
250		274
251	=item json => JSON or JSON::XS object	275	=item json => JSON or JSON::XS object
252		276
253	This is the json coder object used by the C<json> read and write types.	277	This is the json coder object used by the C<json> read and write types.
254		278
255	If you don't supply it, then AnyEvent::Handle will create and use a	279	If you don't supply it, then AnyEvent::Handle will create and use a
256	suitable one, which will write and expect UTF-8 encoded JSON texts.	280	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		281	texts.
257		282
258	Note that you are responsible to depend on the JSON module if you want to	283	Note that you are responsible to depend on the JSON module if you want to
259	use this functionality, as AnyEvent does not have a dependency itself.	284	use this functionality, as AnyEvent does not have a dependency itself.
260		285
261	=item filter_r => $cb
262
263	=item filter_w => $cb
264
265	These exist, but are undocumented at this time.
266
267	=back	286	=back
268		287
269	=cut	288	=cut
270		289
271	sub new {	290	sub new {
…		…
275		294
276	$self->{fh} or Carp::croak "mandatory argument fh is missing";	295	$self->{fh} or Carp::croak "mandatory argument fh is missing";
277		296
278	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	297	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
279		298
280	if ($self->{tls}) {
281	require Net::SSLeay;
282	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	299	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
283	}	300	if $self->{tls};
284		301
285	$self->{_activity} = AnyEvent->now;	302	$self->{_activity} = AnyEvent->now;
286	$self->_timeout;	303	$self->_timeout;
287		304
288	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};	305	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
…		…
295	}	312	}
296		313
297	sub _shutdown {	314	sub _shutdown {
298	my ($self) = @_;	315	my ($self) = @_;
299		316
300	delete $self->{_tw};	317	delete @$self{qw(_tw _rw _ww fh rbuf wbuf on_read _queue)};
301	delete $self->{_rw};
302	delete $self->{_ww};
303	delete $self->{fh};
304		318
305	$self->stoptls;	319	&_freetls;
306
307	delete $self->{on_read};
308	delete $self->{_queue};
309	}	320	}
310		321
311	sub _error {	322	sub _error {
312	my ($self, $errno, $fatal) = @_;	323	my ($self, $errno, $fatal) = @_;
313		324
…		…
316		327
317	$! = $errno;	328	$! = $errno;
318		329
319	if ($self->{on_error}) {	330	if ($self->{on_error}) {
320	$self->{on_error}($self, $fatal);	331	$self->{on_error}($self, $fatal);
321	} else {	332	} elsif ($self->{fh}) {
322	Carp::croak "AnyEvent::Handle uncaught error: $!";	333	Carp::croak "AnyEvent::Handle uncaught error: $!";
323	}	334	}
324	}	335	}
325		336
326	=item $fh = $handle->fh	337	=item $fh = $handle->fh
327		338
328	This method returns the file handle of the L<AnyEvent::Handle> object.	339	This method returns the file handle used to create the L<AnyEvent::Handle> object.
329		340
330	=cut	341	=cut
331		342
332	sub fh { $_[0]{fh} }	343	sub fh { $_[0]{fh} }
333		344
…		…
351	$_[0]{on_eof} = $_[1];	362	$_[0]{on_eof} = $_[1];
352	}	363	}
353		364
354	=item $handle->on_timeout ($cb)	365	=item $handle->on_timeout ($cb)
355		366
356	Replace the current C<on_timeout> callback, or disables the callback	367	Replace the current C<on_timeout> callback, or disables the callback (but
357	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor	368	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
358	argument.	369	argument and method.
359		370
360	=cut	371	=cut
361		372
362	sub on_timeout {	373	sub on_timeout {
363	$_[0]{on_timeout} = $_[1];	374	$_[0]{on_timeout} = $_[1];
364	}	375	}
365		376
366	=item $handle->autocork ($boolean)	377	=item $handle->autocork ($boolean)
367		378
368	Enables or disables the current autocork behaviour (see C<autocork>	379	Enables or disables the current autocork behaviour (see C<autocork>
369	constructor argument).	380	constructor argument). Changes will only take effect on the next write.
370		381
371	=cut	382	=cut
		383
		384	sub autocork {
		385	$_[0]{autocork} = $_[1];
		386	}
372		387
373	=item $handle->no_delay ($boolean)	388	=item $handle->no_delay ($boolean)
374		389
375	Enables or disables the C<no_delay> setting (see constructor argument of	390	Enables or disables the C<no_delay> setting (see constructor argument of
376	the same name for details).	391	the same name for details).
…		…
469	my ($self, $cb) = @_;	484	my ($self, $cb) = @_;
470		485
471	$self->{on_drain} = $cb;	486	$self->{on_drain} = $cb;
472		487
473	$cb->($self)	488	$cb->($self)
474	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	489	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
475	}	490	}
476		491
477	=item $handle->push_write ($data)	492	=item $handle->push_write ($data)
478		493
479	Queues the given scalar to be written. You can push as much data as you	494	Queues the given scalar to be written. You can push as much data as you
…		…
496	substr $self->{wbuf}, 0, $len, "";	511	substr $self->{wbuf}, 0, $len, "";
497		512
498	$self->{_activity} = AnyEvent->now;	513	$self->{_activity} = AnyEvent->now;
499		514
500	$self->{on_drain}($self)	515	$self->{on_drain}($self)
501	if $self->{low_water_mark} >= length $self->{wbuf}	516	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
502	&& $self->{on_drain};	517	&& $self->{on_drain};
503		518
504	delete $self->{_ww} unless length $self->{wbuf};	519	delete $self->{_ww} unless length $self->{wbuf};
505	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	520	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
506	$self->_error ($!, 1);	521	$self->_error ($!, 1);
…		…
530		545
531	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	546	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
532	->($self, @_);	547	->($self, @_);
533	}	548	}
534		549
535	if ($self->{filter_w}) {	550	if ($self->{tls}) {
536	$self->{filter_w}($self, \$_[0]);	551	$self->{_tls_wbuf} .= $_[0];
		552
		553	&_dotls ($self);
537	} else {	554	} else {
538	$self->{wbuf} .= $_[0];	555	$self->{wbuf} .= $_[0];
539	$self->_drain_wbuf;	556	$self->_drain_wbuf;
540	}	557	}
541	}	558	}
…		…
558	=cut	575	=cut
559		576
560	register_write_type netstring => sub {	577	register_write_type netstring => sub {
561	my ($self, $string) = @_;	578	my ($self, $string) = @_;
562		579
563	sprintf "%d:%s,", (length $string), $string	580	(length $string) . ":$string,"
564	};	581	};
565		582
566	=item packstring => $format, $data	583	=item packstring => $format, $data
567		584
568	An octet string prefixed with an encoded length. The encoding C<$format>	585	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
746	) {	763	) {
747	$self->_error (&Errno::ENOSPC, 1), return;	764	$self->_error (&Errno::ENOSPC, 1), return;
748	}	765	}
749		766
750	while () {	767	while () {
		768	# we need to use a separate tls read buffer, as we must not receive data while
		769	# we are draining the buffer, and this can only happen with TLS.
		770	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
		771
751	my $len = length $self->{rbuf};	772	my $len = length $self->{rbuf};
752		773
753	if (my $cb = shift @{ $self->{_queue} }) {	774	if (my $cb = shift @{ $self->{_queue} }) {
754	unless ($cb->($self)) {	775	unless ($cb->($self)) {
755	if ($self->{_eof}) {	776	if ($self->{_eof}) {
…		…
777		798
778	last; # more data might arrive	799	last; # more data might arrive
779	}	800	}
780	} else {	801	} else {
781	# read side becomes idle	802	# read side becomes idle
782	delete $self->{_rw};	803	delete $self->{_rw} unless $self->{tls};
783	last;	804	last;
784	}	805	}
785	}	806	}
786		807
787	if ($self->{_eof}) {	808	if ($self->{_eof}) {
…		…
816		837
817	=item $handle->rbuf	838	=item $handle->rbuf
818		839
819	Returns the read buffer (as a modifiable lvalue).	840	Returns the read buffer (as a modifiable lvalue).
820		841
821	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	842	You can access the read buffer directly as the C<< ->{rbuf} >>
822	you want.	843	member, if you want. However, the only operation allowed on the
		844	read buffer (apart from looking at it) is removing data from its
		845	beginning. Otherwise modifying or appending to it is not allowed and will
		846	lead to hard-to-track-down bugs.
823		847
824	NOTE: The read buffer should only be used or modified if the C<on_read>,	848	NOTE: The read buffer should only be used or modified if the C<on_read>,
825	C<push_read> or C<unshift_read> methods are used. The other read methods	849	C<push_read> or C<unshift_read> methods are used. The other read methods
826	automatically manage the read buffer.	850	automatically manage the read buffer.
827		851
…		…
1082	An octet string prefixed with an encoded length. The encoding C<$format>	1106	An octet string prefixed with an encoded length. The encoding C<$format>
1083	uses the same format as a Perl C<pack> format, but must specify a single	1107	uses the same format as a Perl C<pack> format, but must specify a single
1084	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an	1108	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1085	optional C<!>, C<< < >> or C<< > >> modifier).	1109	optional C<!>, C<< < >> or C<< > >> modifier).
1086		1110
1087	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.	1111	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1112	EPP uses a prefix of C<N> (4 octtes).
1088		1113
1089	Example: read a block of data prefixed by its length in BER-encoded	1114	Example: read a block of data prefixed by its length in BER-encoded
1090	format (very efficient).	1115	format (very efficient).
1091		1116
1092	$handle->push_read (packstring => "w", sub {	1117	$handle->push_read (packstring => "w", sub {
…		…
1122	}	1147	}
1123	};	1148	};
1124		1149
1125	=item json => $cb->($handle, $hash_or_arrayref)	1150	=item json => $cb->($handle, $hash_or_arrayref)
1126		1151
1127	Reads a JSON object or array, decodes it and passes it to the callback.	1152	Reads a JSON object or array, decodes it and passes it to the
		1153	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1128		1154
1129	If a C<json> object was passed to the constructor, then that will be used	1155	If a C<json> object was passed to the constructor, then that will be used
1130	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1156	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1131		1157
1132	This read type uses the incremental parser available with JSON version	1158	This read type uses the incremental parser available with JSON version
…		…
1149	my $rbuf = \$self->{rbuf};	1175	my $rbuf = \$self->{rbuf};
1150		1176
1151	my $json = $self->{json} \|\|= JSON->new->utf8;	1177	my $json = $self->{json} \|\|= JSON->new->utf8;
1152		1178
1153	sub {	1179	sub {
1154	my $ref = $json->incr_parse ($self->{rbuf});	1180	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1155		1181
1156	if ($ref) {	1182	if ($ref) {
1157	$self->{rbuf} = $json->incr_text;	1183	$self->{rbuf} = $json->incr_text;
1158	$json->incr_text = "";	1184	$json->incr_text = "";
1159	$cb->($self, $ref);	1185	$cb->($self, $ref);
1160		1186
1161	1	1187	1
		1188	} elsif ($@) {
		1189	# error case
		1190	$json->incr_skip;
		1191
		1192	$self->{rbuf} = $json->incr_text;
		1193	$json->incr_text = "";
		1194
		1195	$self->_error (&Errno::EBADMSG);
		1196
		1197	()
1162	} else {	1198	} else {
1163	$self->{rbuf} = "";	1199	$self->{rbuf} = "";
		1200
1164	()	1201	()
1165	}	1202	}
1166	}	1203	}
1167	};	1204	};
1168		1205
…		…
1245	Note that AnyEvent::Handle will automatically C<start_read> for you when	1282	Note that AnyEvent::Handle will automatically C<start_read> for you when
1246	you change the C<on_read> callback or push/unshift a read callback, and it	1283	you change the C<on_read> callback or push/unshift a read callback, and it
1247	will automatically C<stop_read> for you when neither C<on_read> is set nor	1284	will automatically C<stop_read> for you when neither C<on_read> is set nor
1248	there are any read requests in the queue.	1285	there are any read requests in the queue.
1249		1286
		1287	These methods will have no effect when in TLS mode (as TLS doesn't support
		1288	half-duplex connections).
		1289
1250	=cut	1290	=cut
1251		1291
1252	sub stop_read {	1292	sub stop_read {
1253	my ($self) = @_;	1293	my ($self) = @_;
1254		1294
1255	delete $self->{_rw};	1295	delete $self->{_rw} unless $self->{tls};
1256	}	1296	}
1257		1297
1258	sub start_read {	1298	sub start_read {
1259	my ($self) = @_;	1299	my ($self) = @_;
1260		1300
1261	unless ($self->{_rw} \|\| $self->{_eof}) {	1301	unless ($self->{_rw} \|\| $self->{_eof}) {
1262	Scalar::Util::weaken $self;	1302	Scalar::Util::weaken $self;
1263		1303
1264	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1304	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1265	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1305	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1266	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;	1306	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;
1267		1307
1268	if ($len > 0) {	1308	if ($len > 0) {
1269	$self->{_activity} = AnyEvent->now;	1309	$self->{_activity} = AnyEvent->now;
1270		1310
1271	$self->{filter_r}	1311	if ($self->{tls}) {
1272	? $self->{filter_r}($self, $rbuf)	1312	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1273	: $self->{_in_drain} \|\| $self->_drain_rbuf;	1313
		1314	&_dotls ($self);
		1315	} else {
		1316	$self->_drain_rbuf unless $self->{_in_drain};
		1317	}
1274		1318
1275	} elsif (defined $len) {	1319	} elsif (defined $len) {
1276	delete $self->{_rw};	1320	delete $self->{_rw};
1277	$self->{_eof} = 1;	1321	$self->{_eof} = 1;
1278	$self->_drain_rbuf unless $self->{_in_drain};	1322	$self->_drain_rbuf unless $self->{_in_drain};
…		…
1282	}	1326	}
1283	});	1327	});
1284	}	1328	}
1285	}	1329	}
1286		1330
		1331	# poll the write BIO and send the data if applicable
1287	sub _dotls {	1332	sub _dotls {
1288	my ($self) = @_;	1333	my ($self) = @_;
1289		1334
1290	my $buf;	1335	my $tmp;
1291		1336
1292	if (length $self->{_tls_wbuf}) {	1337	if (length $self->{_tls_wbuf}) {
1293	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1338	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1294	substr $self->{_tls_wbuf}, 0, $len, "";	1339	substr $self->{_tls_wbuf}, 0, $tmp, "";
1295	}	1340	}
1296	}	1341	}
1297		1342
1298	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1299	$self->{wbuf} .= $buf;
1300	$self->_drain_wbuf;
1301	}
1302
1303	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1343	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1304	if (length $buf) {	1344	unless (length $tmp) {
1305	$self->{rbuf} .= $buf;
1306	$self->_drain_rbuf unless $self->{_in_drain};
1307	} else {
1308	# let's treat SSL-eof as we treat normal EOF	1345	# let's treat SSL-eof as we treat normal EOF
		1346	delete $self->{_rw};
1309	$self->{_eof} = 1;	1347	$self->{_eof} = 1;
1310	$self->_shutdown;	1348	&_freetls;
1311	return;
1312	}	1349	}
1313	}
1314		1350
		1351	$self->{_tls_rbuf} .= $tmp;
		1352	$self->_drain_rbuf unless $self->{_in_drain};
		1353	$self->{tls} or return; # tls session might have gone away in callback
		1354	}
		1355
1315	my $err = Net::SSLeay::get_error ($self->{tls}, -1);	1356	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1316		1357
1317	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {	1358	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1318	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {	1359	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1319	return $self->_error ($!, 1);	1360	return $self->_error ($!, 1);
1320	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1361	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1321	return $self->_error (&Errno::EIO, 1);	1362	return $self->_error (&Errno::EIO, 1);
1322	}	1363	}
1323		1364
1324	# all others are fine for our purposes	1365	# all other errors are fine for our purposes
		1366	}
		1367
		1368	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1369	$self->{wbuf} .= $tmp;
		1370	$self->_drain_wbuf;
1325	}	1371	}
1326	}	1372	}
1327		1373
1328	=item $handle->starttls ($tls[, $tls_ctx])	1374	=item $handle->starttls ($tls[, $tls_ctx])
1329		1375
…		…
1339		1385
1340	The TLS connection object will end up in C<< $handle->{tls} >> after this	1386	The TLS connection object will end up in C<< $handle->{tls} >> after this
1341	call and can be used or changed to your liking. Note that the handshake	1387	call and can be used or changed to your liking. Note that the handshake
1342	might have already started when this function returns.	1388	might have already started when this function returns.
1343		1389
		1390	If it an error to start a TLS handshake more than once per
		1391	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1392
1344	=cut	1393	=cut
1345		1394
1346	sub starttls {	1395	sub starttls {
1347	my ($self, $ssl, $ctx) = @_;	1396	my ($self, $ssl, $ctx) = @_;
1348		1397
1349	$self->stoptls;	1398	require Net::SSLeay;
1350		1399
		1400	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1401	if $self->{tls};
		1402
1351	if ($ssl eq "accept") {	1403	if ($ssl eq "accept") {
1352	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1404	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
1353	Net::SSLeay::set_accept_state ($ssl);	1405	Net::SSLeay::set_accept_state ($ssl);
1354	} elsif ($ssl eq "connect") {	1406	} elsif ($ssl eq "connect") {
1355	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1407	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
…		…
1361	# basically, this is deep magic (because SSL_read should have the same issues)	1413	# basically, this is deep magic (because SSL_read should have the same issues)
1362	# but the openssl maintainers basically said: "trust us, it just works".	1414	# but the openssl maintainers basically said: "trust us, it just works".
1363	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1415	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1364	# and mismaintained ssleay-module doesn't even offer them).	1416	# and mismaintained ssleay-module doesn't even offer them).
1365	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1417	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1418	#
		1419	# in short: this is a mess.
		1420	#
		1421	# note that we do not try to keep the length constant between writes as we are required to do.
		1422	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1423	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1424	# have identity issues in that area.
1366	Net::SSLeay::CTX_set_mode ($self->{tls},	1425	Net::SSLeay::CTX_set_mode ($self->{tls},
1367	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)	1426	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)
1368	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));	1427	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));
1369		1428
1370	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1429	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1371	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1430	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1372		1431
1373	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1432	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1374		1433
1375	$self->{filter_w} = sub {	1434	&_dotls; # need to trigger the initial handshake
1376	$_[0]{_tls_wbuf} .= ${$_[1]};	1435	$self->start_read; # make sure we actually do read
1377	&_dotls;
1378	};
1379	$self->{filter_r} = sub {
1380	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1381	&_dotls;
1382	};
1383	}	1436	}
1384		1437
1385	=item $handle->stoptls	1438	=item $handle->stoptls
1386		1439
1387	Destroys the SSL connection, if any. Partial read or write data will be	1440	Shuts down the SSL connection - this makes a proper EOF handshake by
1388	lost.	1441	sending a close notify to the other side, but since OpenSSL doesn't
		1442	support non-blocking shut downs, it is not possible to re-use the stream
		1443	afterwards.
1389		1444
1390	=cut	1445	=cut
1391		1446
1392	sub stoptls {	1447	sub stoptls {
1393	my ($self) = @_;	1448	my ($self) = @_;
1394		1449
		1450	if ($self->{tls}) {
		1451	Net::SSLeay::shutdown ($self->{tls});
		1452
		1453	&_dotls;
		1454
		1455	# we don't give a shit. no, we do, but we can't. no...
		1456	# we, we... have to use openssl :/
		1457	&_freetls;
		1458	}
		1459	}
		1460
		1461	sub _freetls {
		1462	my ($self) = @_;
		1463
		1464	return unless $self->{tls};
		1465
1395	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1466	Net::SSLeay::free (delete $self->{tls});
1396		1467
1397	delete $self->{_rbio};	1468	delete @$self{qw(_rbio _wbio _tls_wbuf)};
1398	delete $self->{_wbio};
1399	delete $self->{_tls_wbuf};
1400	delete $self->{filter_r};
1401	delete $self->{filter_w};
1402	}	1469	}
1403		1470
1404	sub DESTROY {	1471	sub DESTROY {
1405	my $self = shift;	1472	my ($self) = @_;
1406		1473
1407	$self->stoptls;	1474	&_freetls;
1408		1475
1409	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	1476	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1410		1477
1411	if ($linger && length $self->{wbuf}) {	1478	if ($linger && length $self->{wbuf}) {
1412	my $fh = delete $self->{fh};	1479	my $fh = delete $self->{fh};
…		…
1427	@linger = ();	1494	@linger = ();
1428	});	1495	});
1429	}	1496	}
1430	}	1497	}
1431		1498
		1499	=item $handle->destroy
		1500
		1501	Shuts down the handle object as much as possible - this call ensures that
		1502	no further callbacks will be invoked and resources will be freed as much
		1503	as possible. You must not call any methods on the object afterwards.
		1504
		1505	Normally, you can just "forget" any references to an AnyEvent::Handle
		1506	object and it will simply shut down. This works in fatal error and EOF
		1507	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1508	callback, so when you want to destroy the AnyEvent::Handle object from
		1509	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1510	that case.
		1511
		1512	The handle might still linger in the background and write out remaining
		1513	data, as specified by the C<linger> option, however.
		1514
		1515	=cut
		1516
		1517	sub destroy {
		1518	my ($self) = @_;
		1519
		1520	$self->DESTROY;
		1521	%$self = ();
		1522	}
		1523
1432	=item AnyEvent::Handle::TLS_CTX	1524	=item AnyEvent::Handle::TLS_CTX
1433		1525
1434	This function creates and returns the Net::SSLeay::CTX object used by	1526	This function creates and returns the Net::SSLeay::CTX object used by
1435	default for TLS mode.	1527	default for TLS mode.
1436		1528
…		…
1464	}	1556	}
1465	}	1557	}
1466		1558
1467	=back	1559	=back
1468		1560
		1561
		1562	=head1 NONFREQUENTLY ASKED QUESTIONS
		1563
		1564	=over 4
		1565
		1566	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1567	still get further invocations!
		1568
		1569	That's because AnyEvent::Handle keeps a reference to itself when handling
		1570	read or write callbacks.
		1571
		1572	It is only safe to "forget" the reference inside EOF or error callbacks,
		1573	from within all other callbacks, you need to explicitly call the C<<
		1574	->destroy >> method.
		1575
		1576	=item I get different callback invocations in TLS mode/Why can't I pause
		1577	reading?
		1578
		1579	Unlike, say, TCP, TLS connections do not consist of two independent
		1580	communication channels, one for each direction. Or put differently. The
		1581	read and write directions are not independent of each other: you cannot
		1582	write data unless you are also prepared to read, and vice versa.
		1583
		1584	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1585	callback invocations when you are not expecting any read data - the reason
		1586	is that AnyEvent::Handle always reads in TLS mode.
		1587
		1588	During the connection, you have to make sure that you always have a
		1589	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1590	connection (or when you no longer want to use it) you can call the
		1591	C<destroy> method.
		1592
		1593	=item How do I read data until the other side closes the connection?
		1594
		1595	If you just want to read your data into a perl scalar, the easiest way
		1596	to achieve this is by setting an C<on_read> callback that does nothing,
		1597	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1598	will be in C<$_[0]{rbuf}>:
		1599
		1600	$handle->on_read (sub { });
		1601	$handle->on_eof (undef);
		1602	$handle->on_error (sub {
		1603	my $data = delete $_[0]{rbuf};
		1604	undef $handle;
		1605	});
		1606
		1607	The reason to use C<on_error> is that TCP connections, due to latencies
		1608	and packets loss, might get closed quite violently with an error, when in
		1609	fact, all data has been received.
		1610
		1611	It is usually better to use acknowledgements when transferring data,
		1612	to make sure the other side hasn't just died and you got the data
		1613	intact. This is also one reason why so many internet protocols have an
		1614	explicit QUIT command.
		1615
		1616	=item I don't want to destroy the handle too early - how do I wait until
		1617	all data has been written?
		1618
		1619	After writing your last bits of data, set the C<on_drain> callback
		1620	and destroy the handle in there - with the default setting of
		1621	C<low_water_mark> this will be called precisely when all data has been
		1622	written to the socket:
		1623
		1624	$handle->push_write (...);
		1625	$handle->on_drain (sub {
		1626	warn "all data submitted to the kernel\n";
		1627	undef $handle;
		1628	});
		1629
		1630	=back
		1631
		1632
1469	=head1 SUBCLASSING AnyEvent::Handle	1633	=head1 SUBCLASSING AnyEvent::Handle
1470		1634
1471	In many cases, you might want to subclass AnyEvent::Handle.	1635	In many cases, you might want to subclass AnyEvent::Handle.
1472		1636
1473	To make this easier, a given version of AnyEvent::Handle uses these	1637	To make this easier, a given version of AnyEvent::Handle uses these

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.82 by root, Thu Aug 21 18:45:16 2008 UTC vs. Revision 1.129 by root, Mon Jun 29 11:04:09 2009 UTC

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.82 by root, Thu Aug 21 18:45:16 2008 UTC vs.
Revision 1.129 by root, Mon Jun 29 11:04:09 2009 UTC