[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 1.118 by root, Thu Feb 12 17:33:38 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 = 4.34;
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};
…		…
300	delete $self->{_tw};	317	delete $self->{_tw};
301	delete $self->{_rw};	318	delete $self->{_rw};
302	delete $self->{_ww};	319	delete $self->{_ww};
303	delete $self->{fh};	320	delete $self->{fh};
304		321
305	$self->stoptls;	322	&_freetls;
306		323
307	delete $self->{on_read};	324	delete $self->{on_read};
308	delete $self->{_queue};	325	delete $self->{_queue};
309	}	326	}
310		327
…		…
316		333
317	$! = $errno;	334	$! = $errno;
318		335
319	if ($self->{on_error}) {	336	if ($self->{on_error}) {
320	$self->{on_error}($self, $fatal);	337	$self->{on_error}($self, $fatal);
321	} else {	338	} elsif ($self->{fh}) {
322	Carp::croak "AnyEvent::Handle uncaught error: $!";	339	Carp::croak "AnyEvent::Handle uncaught error: $!";
323	}	340	}
324	}	341	}
325		342
326	=item $fh = $handle->fh	343	=item $fh = $handle->fh
327		344
328	This method returns the file handle of the L<AnyEvent::Handle> object.	345	This method returns the file handle used to create the L<AnyEvent::Handle> object.
329		346
330	=cut	347	=cut
331		348
332	sub fh { $_[0]{fh} }	349	sub fh { $_[0]{fh} }
333		350
…		…
351	$_[0]{on_eof} = $_[1];	368	$_[0]{on_eof} = $_[1];
352	}	369	}
353		370
354	=item $handle->on_timeout ($cb)	371	=item $handle->on_timeout ($cb)
355		372
356	Replace the current C<on_timeout> callback, or disables the callback	373	Replace the current C<on_timeout> callback, or disables the callback (but
357	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor	374	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
358	argument.	375	argument and method.
359		376
360	=cut	377	=cut
361		378
362	sub on_timeout {	379	sub on_timeout {
363	$_[0]{on_timeout} = $_[1];	380	$_[0]{on_timeout} = $_[1];
364	}	381	}
365		382
366	=item $handle->autocork ($boolean)	383	=item $handle->autocork ($boolean)
367		384
368	Enables or disables the current autocork behaviour (see C<autocork>	385	Enables or disables the current autocork behaviour (see C<autocork>
369	constructor argument).	386	constructor argument). Changes will only take effect on the next write.
370		387
371	=cut	388	=cut
		389
		390	sub autocork {
		391	$_[0]{autocork} = $_[1];
		392	}
372		393
373	=item $handle->no_delay ($boolean)	394	=item $handle->no_delay ($boolean)
374		395
375	Enables or disables the C<no_delay> setting (see constructor argument of	396	Enables or disables the C<no_delay> setting (see constructor argument of
376	the same name for details).	397	the same name for details).
…		…
469	my ($self, $cb) = @_;	490	my ($self, $cb) = @_;
470		491
471	$self->{on_drain} = $cb;	492	$self->{on_drain} = $cb;
472		493
473	$cb->($self)	494	$cb->($self)
474	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	495	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
475	}	496	}
476		497
477	=item $handle->push_write ($data)	498	=item $handle->push_write ($data)
478		499
479	Queues the given scalar to be written. You can push as much data as you	500	Queues the given scalar to be written. You can push as much data as you
…		…
496	substr $self->{wbuf}, 0, $len, "";	517	substr $self->{wbuf}, 0, $len, "";
497		518
498	$self->{_activity} = AnyEvent->now;	519	$self->{_activity} = AnyEvent->now;
499		520
500	$self->{on_drain}($self)	521	$self->{on_drain}($self)
501	if $self->{low_water_mark} >= length $self->{wbuf}	522	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
502	&& $self->{on_drain};	523	&& $self->{on_drain};
503		524
504	delete $self->{_ww} unless length $self->{wbuf};	525	delete $self->{_ww} unless length $self->{wbuf};
505	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	526	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
506	$self->_error ($!, 1);	527	$self->_error ($!, 1);
…		…
530		551
531	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	552	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
532	->($self, @_);	553	->($self, @_);
533	}	554	}
534		555
535	if ($self->{filter_w}) {	556	if ($self->{tls}) {
536	$self->{filter_w}($self, \$_[0]);	557	$self->{_tls_wbuf} .= $_[0];
		558
		559	&_dotls ($self);
537	} else {	560	} else {
538	$self->{wbuf} .= $_[0];	561	$self->{wbuf} .= $_[0];
539	$self->_drain_wbuf;	562	$self->_drain_wbuf;
540	}	563	}
541	}	564	}
…		…
558	=cut	581	=cut
559		582
560	register_write_type netstring => sub {	583	register_write_type netstring => sub {
561	my ($self, $string) = @_;	584	my ($self, $string) = @_;
562		585
563	sprintf "%d:%s,", (length $string), $string	586	(length $string) . ":$string,"
564	};	587	};
565		588
566	=item packstring => $format, $data	589	=item packstring => $format, $data
567		590
568	An octet string prefixed with an encoded length. The encoding C<$format>	591	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
746	) {	769	) {
747	$self->_error (&Errno::ENOSPC, 1), return;	770	$self->_error (&Errno::ENOSPC, 1), return;
748	}	771	}
749		772
750	while () {	773	while () {
		774	# we need to use a separate tls read buffer, as we must not receive data while
		775	# we are draining the buffer, and this can only happen with TLS.
		776	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
		777
751	my $len = length $self->{rbuf};	778	my $len = length $self->{rbuf};
752		779
753	if (my $cb = shift @{ $self->{_queue} }) {	780	if (my $cb = shift @{ $self->{_queue} }) {
754	unless ($cb->($self)) {	781	unless ($cb->($self)) {
755	if ($self->{_eof}) {	782	if ($self->{_eof}) {
…		…
777		804
778	last; # more data might arrive	805	last; # more data might arrive
779	}	806	}
780	} else {	807	} else {
781	# read side becomes idle	808	# read side becomes idle
782	delete $self->{_rw};	809	delete $self->{_rw} unless $self->{tls};
783	last;	810	last;
784	}	811	}
785	}	812	}
786		813
787	if ($self->{_eof}) {	814	if ($self->{_eof}) {
…		…
816		843
817	=item $handle->rbuf	844	=item $handle->rbuf
818		845
819	Returns the read buffer (as a modifiable lvalue).	846	Returns the read buffer (as a modifiable lvalue).
820		847
821	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	848	You can access the read buffer directly as the C<< ->{rbuf} >>
822	you want.	849	member, if you want. However, the only operation allowed on the
		850	read buffer (apart from looking at it) is removing data from its
		851	beginning. Otherwise modifying or appending to it is not allowed and will
		852	lead to hard-to-track-down bugs.
823		853
824	NOTE: The read buffer should only be used or modified if the C<on_read>,	854	NOTE: The read buffer should only be used or modified if the C<on_read>,
825	C<push_read> or C<unshift_read> methods are used. The other read methods	855	C<push_read> or C<unshift_read> methods are used. The other read methods
826	automatically manage the read buffer.	856	automatically manage the read buffer.
827		857
…		…
1082	An octet string prefixed with an encoded length. The encoding C<$format>	1112	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	1113	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	1114	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1085	optional C<!>, C<< < >> or C<< > >> modifier).	1115	optional C<!>, C<< < >> or C<< > >> modifier).
1086		1116
1087	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.	1117	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1118	EPP uses a prefix of C<N> (4 octtes).
1088		1119
1089	Example: read a block of data prefixed by its length in BER-encoded	1120	Example: read a block of data prefixed by its length in BER-encoded
1090	format (very efficient).	1121	format (very efficient).
1091		1122
1092	$handle->push_read (packstring => "w", sub {	1123	$handle->push_read (packstring => "w", sub {
…		…
1122	}	1153	}
1123	};	1154	};
1124		1155
1125	=item json => $cb->($handle, $hash_or_arrayref)	1156	=item json => $cb->($handle, $hash_or_arrayref)
1126		1157
1127	Reads a JSON object or array, decodes it and passes it to the callback.	1158	Reads a JSON object or array, decodes it and passes it to the
		1159	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1128		1160
1129	If a C<json> object was passed to the constructor, then that will be used	1161	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.	1162	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1131		1163
1132	This read type uses the incremental parser available with JSON version	1164	This read type uses the incremental parser available with JSON version
…		…
1149	my $rbuf = \$self->{rbuf};	1181	my $rbuf = \$self->{rbuf};
1150		1182
1151	my $json = $self->{json} \|\|= JSON->new->utf8;	1183	my $json = $self->{json} \|\|= JSON->new->utf8;
1152		1184
1153	sub {	1185	sub {
1154	my $ref = $json->incr_parse ($self->{rbuf});	1186	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1155		1187
1156	if ($ref) {	1188	if ($ref) {
1157	$self->{rbuf} = $json->incr_text;	1189	$self->{rbuf} = $json->incr_text;
1158	$json->incr_text = "";	1190	$json->incr_text = "";
1159	$cb->($self, $ref);	1191	$cb->($self, $ref);
1160		1192
1161	1	1193	1
		1194	} elsif ($@) {
		1195	# error case
		1196	$json->incr_skip;
		1197
		1198	$self->{rbuf} = $json->incr_text;
		1199	$json->incr_text = "";
		1200
		1201	$self->_error (&Errno::EBADMSG);
		1202
		1203	()
1162	} else {	1204	} else {
1163	$self->{rbuf} = "";	1205	$self->{rbuf} = "";
		1206
1164	()	1207	()
1165	}	1208	}
1166	}	1209	}
1167	};	1210	};
1168		1211
…		…
1245	Note that AnyEvent::Handle will automatically C<start_read> for you when	1288	Note that AnyEvent::Handle will automatically C<start_read> for you when
1246	you change the C<on_read> callback or push/unshift a read callback, and it	1289	you change the C<on_read> callback or push/unshift a read callback, and it
1247	will automatically C<stop_read> for you when neither C<on_read> is set nor	1290	will automatically C<stop_read> for you when neither C<on_read> is set nor
1248	there are any read requests in the queue.	1291	there are any read requests in the queue.
1249		1292
		1293	These methods will have no effect when in TLS mode (as TLS doesn't support
		1294	half-duplex connections).
		1295
1250	=cut	1296	=cut
1251		1297
1252	sub stop_read {	1298	sub stop_read {
1253	my ($self) = @_;	1299	my ($self) = @_;
1254		1300
1255	delete $self->{_rw};	1301	delete $self->{_rw} unless $self->{tls};
1256	}	1302	}
1257		1303
1258	sub start_read {	1304	sub start_read {
1259	my ($self) = @_;	1305	my ($self) = @_;
1260		1306
1261	unless ($self->{_rw} \|\| $self->{_eof}) {	1307	unless ($self->{_rw} \|\| $self->{_eof}) {
1262	Scalar::Util::weaken $self;	1308	Scalar::Util::weaken $self;
1263		1309
1264	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1310	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1265	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1311	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1266	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;	1312	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;
1267		1313
1268	if ($len > 0) {	1314	if ($len > 0) {
1269	$self->{_activity} = AnyEvent->now;	1315	$self->{_activity} = AnyEvent->now;
1270		1316
1271	$self->{filter_r}	1317	if ($self->{tls}) {
1272	? $self->{filter_r}($self, $rbuf)	1318	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1273	: $self->{_in_drain} \|\| $self->_drain_rbuf;	1319
		1320	&_dotls ($self);
		1321	} else {
		1322	$self->_drain_rbuf unless $self->{_in_drain};
		1323	}
1274		1324
1275	} elsif (defined $len) {	1325	} elsif (defined $len) {
1276	delete $self->{_rw};	1326	delete $self->{_rw};
1277	$self->{_eof} = 1;	1327	$self->{_eof} = 1;
1278	$self->_drain_rbuf unless $self->{_in_drain};	1328	$self->_drain_rbuf unless $self->{_in_drain};
…		…
1282	}	1332	}
1283	});	1333	});
1284	}	1334	}
1285	}	1335	}
1286		1336
		1337	# poll the write BIO and send the data if applicable
1287	sub _dotls {	1338	sub _dotls {
1288	my ($self) = @_;	1339	my ($self) = @_;
1289		1340
1290	my $buf;	1341	my $tmp;
1291		1342
1292	if (length $self->{_tls_wbuf}) {	1343	if (length $self->{_tls_wbuf}) {
1293	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1344	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1294	substr $self->{_tls_wbuf}, 0, $len, "";	1345	substr $self->{_tls_wbuf}, 0, $tmp, "";
1295	}	1346	}
1296	}	1347	}
1297		1348
1298	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1299	$self->{wbuf} .= $buf;
1300	$self->_drain_wbuf;
1301	}
1302
1303	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1349	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1304	if (length $buf) {	1350	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	1351	# let's treat SSL-eof as we treat normal EOF
		1352	delete $self->{_rw};
1309	$self->{_eof} = 1;	1353	$self->{_eof} = 1;
1310	$self->_shutdown;	1354	&_freetls;
1311	return;
1312	}	1355	}
1313	}
1314		1356
		1357	$self->{_tls_rbuf} .= $tmp;
		1358	$self->_drain_rbuf unless $self->{_in_drain};
		1359	$self->{tls} or return; # tls session might have gone away in callback
		1360	}
		1361
1315	my $err = Net::SSLeay::get_error ($self->{tls}, -1);	1362	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1316		1363
1317	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {	1364	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1318	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {	1365	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1319	return $self->_error ($!, 1);	1366	return $self->_error ($!, 1);
1320	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1367	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1321	return $self->_error (&Errno::EIO, 1);	1368	return $self->_error (&Errno::EIO, 1);
1322	}	1369	}
1323		1370
1324	# all others are fine for our purposes	1371	# all other errors are fine for our purposes
		1372	}
		1373
		1374	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1375	$self->{wbuf} .= $tmp;
		1376	$self->_drain_wbuf;
1325	}	1377	}
1326	}	1378	}
1327		1379
1328	=item $handle->starttls ($tls[, $tls_ctx])	1380	=item $handle->starttls ($tls[, $tls_ctx])
1329		1381
…		…
1339		1391
1340	The TLS connection object will end up in C<< $handle->{tls} >> after this	1392	The TLS connection object will end up in C<< $handle->{tls} >> after this
1341	call and can be used or changed to your liking. Note that the handshake	1393	call and can be used or changed to your liking. Note that the handshake
1342	might have already started when this function returns.	1394	might have already started when this function returns.
1343		1395
		1396	If it an error to start a TLS handshake more than once per
		1397	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1398
1344	=cut	1399	=cut
1345		1400
1346	sub starttls {	1401	sub starttls {
1347	my ($self, $ssl, $ctx) = @_;	1402	my ($self, $ssl, $ctx) = @_;
1348		1403
1349	$self->stoptls;	1404	require Net::SSLeay;
1350		1405
		1406	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1407	if $self->{tls};
		1408
1351	if ($ssl eq "accept") {	1409	if ($ssl eq "accept") {
1352	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1410	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
1353	Net::SSLeay::set_accept_state ($ssl);	1411	Net::SSLeay::set_accept_state ($ssl);
1354	} elsif ($ssl eq "connect") {	1412	} elsif ($ssl eq "connect") {
1355	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1413	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
…		…
1361	# basically, this is deep magic (because SSL_read should have the same issues)	1419	# 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".	1420	# but the openssl maintainers basically said: "trust us, it just works".
1363	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1421	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1364	# and mismaintained ssleay-module doesn't even offer them).	1422	# and mismaintained ssleay-module doesn't even offer them).
1365	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1423	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1424	#
		1425	# in short: this is a mess.
		1426	#
		1427	# note that we do not try to keep the length constant between writes as we are required to do.
		1428	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1429	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1430	# have identity issues in that area.
1366	Net::SSLeay::CTX_set_mode ($self->{tls},	1431	Net::SSLeay::CTX_set_mode ($self->{tls},
1367	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)	1432	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)
1368	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));	1433	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));
1369		1434
1370	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1435	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1371	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1436	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1372		1437
1373	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1438	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1374		1439
1375	$self->{filter_w} = sub {	1440	&_dotls; # need to trigger the initial handshake
1376	$_[0]{_tls_wbuf} .= ${$_[1]};	1441	$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	}	1442	}
1384		1443
1385	=item $handle->stoptls	1444	=item $handle->stoptls
1386		1445
1387	Destroys the SSL connection, if any. Partial read or write data will be	1446	Shuts down the SSL connection - this makes a proper EOF handshake by
1388	lost.	1447	sending a close notify to the other side, but since OpenSSL doesn't
		1448	support non-blocking shut downs, it is not possible to re-use the stream
		1449	afterwards.
1389		1450
1390	=cut	1451	=cut
1391		1452
1392	sub stoptls {	1453	sub stoptls {
1393	my ($self) = @_;	1454	my ($self) = @_;
1394		1455
		1456	if ($self->{tls}) {
		1457	Net::SSLeay::shutdown ($self->{tls});
		1458
		1459	&_dotls;
		1460
		1461	# we don't give a shit. no, we do, but we can't. no...
		1462	# we, we... have to use openssl :/
		1463	&_freetls;
		1464	}
		1465	}
		1466
		1467	sub _freetls {
		1468	my ($self) = @_;
		1469
		1470	return unless $self->{tls};
		1471
1395	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1472	Net::SSLeay::free (delete $self->{tls});
1396		1473
1397	delete $self->{_rbio};	1474	delete @$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	}	1475	}
1403		1476
1404	sub DESTROY {	1477	sub DESTROY {
1405	my $self = shift;	1478	my $self = shift;
1406		1479
1407	$self->stoptls;	1480	&_freetls;
1408		1481
1409	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	1482	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1410		1483
1411	if ($linger && length $self->{wbuf}) {	1484	if ($linger && length $self->{wbuf}) {
1412	my $fh = delete $self->{fh};	1485	my $fh = delete $self->{fh};
…		…
1427	@linger = ();	1500	@linger = ();
1428	});	1501	});
1429	}	1502	}
1430	}	1503	}
1431		1504
		1505	=item $handle->destroy
		1506
		1507	Shuts down the handle object as much as possible - this call ensures that
		1508	no further callbacks will be invoked and resources will be freed as much
		1509	as possible. You must not call any methods on the object afterwards.
		1510
		1511	Normally, you can just "forget" any references to an AnyEvent::Handle
		1512	object and it will simply shut down. This works in fatal error and EOF
		1513	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1514	callback, so when you want to destroy the AnyEvent::Handle object from
		1515	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1516	that case.
		1517
		1518	The handle might still linger in the background and write out remaining
		1519	data, as specified by the C<linger> option, however.
		1520
		1521	=cut
		1522
		1523	sub destroy {
		1524	my ($self) = @_;
		1525
		1526	$self->DESTROY;
		1527	%$self = ();
		1528	}
		1529
1432	=item AnyEvent::Handle::TLS_CTX	1530	=item AnyEvent::Handle::TLS_CTX
1433		1531
1434	This function creates and returns the Net::SSLeay::CTX object used by	1532	This function creates and returns the Net::SSLeay::CTX object used by
1435	default for TLS mode.	1533	default for TLS mode.
1436		1534
…		…
1464	}	1562	}
1465	}	1563	}
1466		1564
1467	=back	1565	=back
1468		1566
		1567
		1568	=head1 NONFREQUENTLY ASKED QUESTIONS
		1569
		1570	=over 4
		1571
		1572	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1573	still get further invocations!
		1574
		1575	That's because AnyEvent::Handle keeps a reference to itself when handling
		1576	read or write callbacks.
		1577
		1578	It is only safe to "forget" the reference inside EOF or error callbacks,
		1579	from within all other callbacks, you need to explicitly call the C<<
		1580	->destroy >> method.
		1581
		1582	=item I get different callback invocations in TLS mode/Why can't I pause
		1583	reading?
		1584
		1585	Unlike, say, TCP, TLS connections do not consist of two independent
		1586	communication channels, one for each direction. Or put differently. The
		1587	read and write directions are not independent of each other: you cannot
		1588	write data unless you are also prepared to read, and vice versa.
		1589
		1590	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1591	callback invocations when you are not expecting any read data - the reason
		1592	is that AnyEvent::Handle always reads in TLS mode.
		1593
		1594	During the connection, you have to make sure that you always have a
		1595	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1596	connection (or when you no longer want to use it) you can call the
		1597	C<destroy> method.
		1598
		1599	=item How do I read data until the other side closes the connection?
		1600
		1601	If you just want to read your data into a perl scalar, the easiest way
		1602	to achieve this is by setting an C<on_read> callback that does nothing,
		1603	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1604	will be in C<$_[0]{rbuf}>:
		1605
		1606	$handle->on_read (sub { });
		1607	$handle->on_eof (undef);
		1608	$handle->on_error (sub {
		1609	my $data = delete $_[0]{rbuf};
		1610	undef $handle;
		1611	});
		1612
		1613	The reason to use C<on_error> is that TCP connections, due to latencies
		1614	and packets loss, might get closed quite violently with an error, when in
		1615	fact, all data has been received.
		1616
		1617	It is usually better to use acknowledgements when transferring data,
		1618	to make sure the other side hasn't just died and you got the data
		1619	intact. This is also one reason why so many internet protocols have an
		1620	explicit QUIT command.
		1621
		1622	=item I don't want to destroy the handle too early - how do I wait until
		1623	all data has been written?
		1624
		1625	After writing your last bits of data, set the C<on_drain> callback
		1626	and destroy the handle in there - with the default setting of
		1627	C<low_water_mark> this will be called precisely when all data has been
		1628	written to the socket:
		1629
		1630	$handle->push_write (...);
		1631	$handle->on_drain (sub {
		1632	warn "all data submitted to the kernel\n";
		1633	undef $handle;
		1634	});
		1635
		1636	=back
		1637
		1638
1469	=head1 SUBCLASSING AnyEvent::Handle	1639	=head1 SUBCLASSING AnyEvent::Handle
1470		1640
1471	In many cases, you might want to subclass AnyEvent::Handle.	1641	In many cases, you might want to subclass AnyEvent::Handle.
1472		1642
1473	To make this easier, a given version of AnyEvent::Handle uses these	1643	To make this easier, a given version of AnyEvent::Handle uses these

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.82 by root, Thu Aug 21 18:45:16 2008 UTC vs. Revision 1.118 by root, Thu Feb 12 17:33:38 2009 UTC

Diff Legend

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.82 by root, Thu Aug 21 18:45:16 2008 UTC vs.
Revision 1.118 by root, Thu Feb 12 17:33:38 2009 UTC