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

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.83 by root, Thu Aug 21 19:11:37 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
…		…
81	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,
82	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
83	connection cleanly.	86	connection cleanly.
84		87
85	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,
86	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
87	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
88	down.	91	down.
89		92
90	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,
91	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
92	waiting for data.	95	waiting for data.
93		96
94	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
95	set, then a fatal error will be raised with C<$!> set to <0>.	98	set, then a fatal error will be raised with C<$!> set to <0>.
…		…
100	occured, such as not being able to resolve the hostname, failure to	103	occured, such as not being able to resolve the hostname, failure to
101	connect or a read error.	104	connect or a read error.
102		105
103	Some errors are fatal (which is indicated by C<$fatal> being true). On	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
104	fatal errors the handle object will be shut down and will not be usable	107	fatal errors the handle object will be shut down and will not be usable
105	(but you are free to look at the current C< ->rbuf >). Examples of fatal	108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
106	errors are an EOF condition with active (but unsatisifable) read watchers	109	errors are an EOF condition with active (but unsatisifable) read watchers
107	(C<EPIPE>) or I/O errors.	110	(C<EPIPE>) or I/O errors.
108		111
109	Non-fatal errors can be retried by simply returning, but it is recommended	112	Non-fatal errors can be retried by simply returning, but it is recommended
110	to simply ignore this parameter and instead abondon the handle object	113	to simply ignore this parameter and instead abondon the handle object
…		…
124	and no read request is in the queue (unlike read queue callbacks, this	127	and no read request is in the queue (unlike read queue callbacks, this
125	callback will only be called when at least one octet of data is in the	128	callback will only be called when at least one octet of data is in the
126	read buffer).	129	read buffer).
127		130
128	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	131	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
129	method or access the C<$handle->{rbuf}> member directly.	132	method or access the C<$handle->{rbuf}> member directly. Note that you
		133	must not enlarge or modify the read buffer, you can only remove data at
		134	the beginning from it.
130		135
131	When an EOF condition is detected then AnyEvent::Handle will first try to	136	When an EOF condition is detected then AnyEvent::Handle will first try to
132	feed all the remaining data to the queued callbacks and C<on_read> before	137	feed all the remaining data to the queued callbacks and C<on_read> before
133	calling the C<on_eof> callback. If no progress can be made, then a fatal	138	calling the C<on_eof> callback. If no progress can be made, then a fatal
134	error will be raised (with C<$!> set to C<EPIPE>).	139	error will be raised (with C<$!> set to C<EPIPE>).
…		…
149	=item timeout => $fractional_seconds	154	=item timeout => $fractional_seconds
150		155
151	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
152	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
153	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
154	missing, an C<ETIMEDOUT> error will be raised).	159	missing, a non-fatal C<ETIMEDOUT> error will be raised).
155		160
156	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
157	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
158	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
159	in the C<on_timeout> callback.	164	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		165	restart the timeout.
160		166
161	Zero (the default) disables this timeout.	167	Zero (the default) disables this timeout.
162		168
163	=item on_timeout => $cb->($handle)	169	=item on_timeout => $cb->($handle)
164		170
…		…
168		174
169	=item rbuf_max => <bytes>	175	=item rbuf_max => <bytes>
170		176
171	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>)
172	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
173	avoid denial-of-service attacks.	179	avoid some forms of denial-of-service attacks.
174		180
175	For example, a server accepting connections from untrusted sources should	181	For example, a server accepting connections from untrusted sources should
176	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
177	(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
178	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
179	isn't finished).	185	isn't finished).
180		186
181	=item autocork => <boolean>	187	=item autocork => <boolean>
182		188
183	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
184	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
185	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
186	inefficient if you write multiple small chunks (this disadvantage is	192	be inefficient if you write multiple small chunks (on the wire, this
187	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).
188		195
189	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
190	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,
191	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.
192		200
193	=item no_delay => <boolean>	201	=item no_delay => <boolean>
194		202
195	When doing small writes on sockets, your operating system kernel might	203	When doing small writes on sockets, your operating system kernel might
196	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
197	the Nagle algorithm, and usually it is beneficial.	205	the Nagle algorithm, and usually it is beneficial.
198		206
199	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
200	accomplishd by setting this option to true.	208	accomplishd by setting this option to a true value.
201		209
202	The default is your opertaing system's default behaviour, this option	210	The default is your opertaing system's default behaviour (most likely
203	explicitly enables or disables it, if possible.	211	enabled), this option explicitly enables or disables it, if possible.
204		212
205	=item read_size => <bytes>	213	=item read_size => <bytes>
206		214
207	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
208	during each (loop iteration). Default: C<8192>.	216	try to read during each loop iteration, which affects memory
		217	requirements). Default: C<8192>.
209		218
210	=item low_water_mark => <bytes>	219	=item low_water_mark => <bytes>
211		220
212	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
213	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
214	considered empty.	223	considered empty.
215		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
216	=item linger => <seconds>	230	=item linger => <seconds>
217		231
218	If non-zero (default: C<3600>), then the destructor of the	232	If non-zero (default: C<3600>), then the destructor of the
219	AnyEvent::Handle object will check wether there is still outstanding write	233	AnyEvent::Handle object will check whether there is still outstanding
220	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
221	will be reported (this mostly matches how the operating system treats	235	socket. No errors will be reported (this mostly matches how the operating
222	outstanding data at socket close time).	236	system treats outstanding data at socket close time).
223		237
224	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
225	encoded. This data will be lost.	239	yet. This data will be lost. Calling the C<stoptls> method in time might
		240	help.
226		241
227	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object	242	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object
228		243
229	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
230	will start making tls handshake and will transparently encrypt/decrypt	245	AnyEvent will start a TLS handshake as soon as the conenction has been
231	data.	246	established and will transparently encrypt/decrypt data afterwards.
232		247
233	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
234	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.
235		252
236	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
237	connection, use C<connect> mode.	254	C<accept>, and for the TLS client side of a connection, use C<connect>
		255	mode.
238		256
239	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
240	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>
241	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
242	AnyEvent::Handle.	260	AnyEvent::Handle.
243		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
244	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.
245		268
246	=item tls_ctx => $ssl_ctx	269	=item tls_ctx => $ssl_ctx
247		270
248	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
249	(unless a connection object was specified directly). If this parameter is	272	(unless a connection object was specified directly). If this parameter is
250	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	273	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
251		274
252	=item json => JSON or JSON::XS object	275	=item json => JSON or JSON::XS object
253		276
254	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.
255		278
256	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
257	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.
258		282
259	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
260	use this functionality, as AnyEvent does not have a dependency itself.	284	use this functionality, as AnyEvent does not have a dependency itself.
261		285
262	=item filter_r => $cb
263
264	=item filter_w => $cb
265
266	These exist, but are undocumented at this time.
267
268	=back	286	=back
269		287
270	=cut	288	=cut
271		289
272	sub new {	290	sub new {
…		…
276		294
277	$self->{fh} or Carp::croak "mandatory argument fh is missing";	295	$self->{fh} or Carp::croak "mandatory argument fh is missing";
278		296
279	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	297	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
280		298
281	if ($self->{tls}) {
282	require Net::SSLeay;
283	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	299	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
284	}	300	if $self->{tls};
285		301
286	$self->{_activity} = AnyEvent->now;	302	$self->{_activity} = AnyEvent->now;
287	$self->_timeout;	303	$self->_timeout;
288		304
289	$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};
…		…
301	delete $self->{_tw};	317	delete $self->{_tw};
302	delete $self->{_rw};	318	delete $self->{_rw};
303	delete $self->{_ww};	319	delete $self->{_ww};
304	delete $self->{fh};	320	delete $self->{fh};
305		321
306	$self->stoptls;	322	&_freetls;
307		323
308	delete $self->{on_read};	324	delete $self->{on_read};
309	delete $self->{_queue};	325	delete $self->{_queue};
310	}	326	}
311		327
…		…
317		333
318	$! = $errno;	334	$! = $errno;
319		335
320	if ($self->{on_error}) {	336	if ($self->{on_error}) {
321	$self->{on_error}($self, $fatal);	337	$self->{on_error}($self, $fatal);
322	} else {	338	} elsif ($self->{fh}) {
323	Carp::croak "AnyEvent::Handle uncaught error: $!";	339	Carp::croak "AnyEvent::Handle uncaught error: $!";
324	}	340	}
325	}	341	}
326		342
327	=item $fh = $handle->fh	343	=item $fh = $handle->fh
328		344
329	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.
330		346
331	=cut	347	=cut
332		348
333	sub fh { $_[0]{fh} }	349	sub fh { $_[0]{fh} }
334		350
…		…
352	$_[0]{on_eof} = $_[1];	368	$_[0]{on_eof} = $_[1];
353	}	369	}
354		370
355	=item $handle->on_timeout ($cb)	371	=item $handle->on_timeout ($cb)
356		372
357	Replace the current C<on_timeout> callback, or disables the callback	373	Replace the current C<on_timeout> callback, or disables the callback (but
358	(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
359	argument.	375	argument and method.
360		376
361	=cut	377	=cut
362		378
363	sub on_timeout {	379	sub on_timeout {
364	$_[0]{on_timeout} = $_[1];	380	$_[0]{on_timeout} = $_[1];
365	}	381	}
366		382
367	=item $handle->autocork ($boolean)	383	=item $handle->autocork ($boolean)
368		384
369	Enables or disables the current autocork behaviour (see C<autocork>	385	Enables or disables the current autocork behaviour (see C<autocork>
370	constructor argument).	386	constructor argument). Changes will only take effect on the next write.
371		387
372	=cut	388	=cut
		389
		390	sub autocork {
		391	$_[0]{autocork} = $_[1];
		392	}
373		393
374	=item $handle->no_delay ($boolean)	394	=item $handle->no_delay ($boolean)
375		395
376	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
377	the same name for details).	397	the same name for details).
…		…
470	my ($self, $cb) = @_;	490	my ($self, $cb) = @_;
471		491
472	$self->{on_drain} = $cb;	492	$self->{on_drain} = $cb;
473		493
474	$cb->($self)	494	$cb->($self)
475	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	495	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
476	}	496	}
477		497
478	=item $handle->push_write ($data)	498	=item $handle->push_write ($data)
479		499
480	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
…		…
497	substr $self->{wbuf}, 0, $len, "";	517	substr $self->{wbuf}, 0, $len, "";
498		518
499	$self->{_activity} = AnyEvent->now;	519	$self->{_activity} = AnyEvent->now;
500		520
501	$self->{on_drain}($self)	521	$self->{on_drain}($self)
502	if $self->{low_water_mark} >= length $self->{wbuf}	522	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
503	&& $self->{on_drain};	523	&& $self->{on_drain};
504		524
505	delete $self->{_ww} unless length $self->{wbuf};	525	delete $self->{_ww} unless length $self->{wbuf};
506	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	526	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
507	$self->_error ($!, 1);	527	$self->_error ($!, 1);
…		…
531		551
532	@_ = ($WH{$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")
533	->($self, @_);	553	->($self, @_);
534	}	554	}
535		555
536	if ($self->{filter_w}) {	556	if ($self->{tls}) {
537	$self->{filter_w}($self, \$_[0]);	557	$self->{_tls_wbuf} .= $_[0];
		558
		559	&_dotls ($self);
538	} else {	560	} else {
539	$self->{wbuf} .= $_[0];	561	$self->{wbuf} .= $_[0];
540	$self->_drain_wbuf;	562	$self->_drain_wbuf;
541	}	563	}
542	}	564	}
…		…
559	=cut	581	=cut
560		582
561	register_write_type netstring => sub {	583	register_write_type netstring => sub {
562	my ($self, $string) = @_;	584	my ($self, $string) = @_;
563		585
564	sprintf "%d:%s,", (length $string), $string	586	(length $string) . ":$string,"
565	};	587	};
566		588
567	=item packstring => $format, $data	589	=item packstring => $format, $data
568		590
569	An octet string prefixed with an encoded length. The encoding C<$format>	591	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
747	) {	769	) {
748	$self->_error (&Errno::ENOSPC, 1), return;	770	$self->_error (&Errno::ENOSPC, 1), return;
749	}	771	}
750		772
751	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
752	my $len = length $self->{rbuf};	778	my $len = length $self->{rbuf};
753		779
754	if (my $cb = shift @{ $self->{_queue} }) {	780	if (my $cb = shift @{ $self->{_queue} }) {
755	unless ($cb->($self)) {	781	unless ($cb->($self)) {
756	if ($self->{_eof}) {	782	if ($self->{_eof}) {
…		…
778		804
779	last; # more data might arrive	805	last; # more data might arrive
780	}	806	}
781	} else {	807	} else {
782	# read side becomes idle	808	# read side becomes idle
783	delete $self->{_rw};	809	delete $self->{_rw} unless $self->{tls};
784	last;	810	last;
785	}	811	}
786	}	812	}
787		813
788	if ($self->{_eof}) {	814	if ($self->{_eof}) {
…		…
817		843
818	=item $handle->rbuf	844	=item $handle->rbuf
819		845
820	Returns the read buffer (as a modifiable lvalue).	846	Returns the read buffer (as a modifiable lvalue).
821		847
822	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	848	You can access the read buffer directly as the C<< ->{rbuf} >>
823	you want.	849	member, if you want. However, the only operation allowed on the
		850	read buffer (apart from looking at it) is removing data from its
		851	beginning. Otherwise modifying or appending to it is not allowed and will
		852	lead to hard-to-track-down bugs.
824		853
825	NOTE: The read buffer should only be used or modified if the C<on_read>,	854	NOTE: The read buffer should only be used or modified if the C<on_read>,
826	C<push_read> or C<unshift_read> methods are used. The other read methods	855	C<push_read> or C<unshift_read> methods are used. The other read methods
827	automatically manage the read buffer.	856	automatically manage the read buffer.
828		857
…		…
1083	An octet string prefixed with an encoded length. The encoding C<$format>	1112	An octet string prefixed with an encoded length. The encoding C<$format>
1084	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
1085	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an	1114	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1086	optional C<!>, C<< < >> or C<< > >> modifier).	1115	optional C<!>, C<< < >> or C<< > >> modifier).
1087		1116
1088	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).
1089		1119
1090	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
1091	format (very efficient).	1121	format (very efficient).
1092		1122
1093	$handle->push_read (packstring => "w", sub {	1123	$handle->push_read (packstring => "w", sub {
…		…
1123	}	1153	}
1124	};	1154	};
1125		1155
1126	=item json => $cb->($handle, $hash_or_arrayref)	1156	=item json => $cb->($handle, $hash_or_arrayref)
1127		1157
1128	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.
1129		1160
1130	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
1131	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.
1132		1163
1133	This read type uses the incremental parser available with JSON version	1164	This read type uses the incremental parser available with JSON version
…		…
1150	my $rbuf = \$self->{rbuf};	1181	my $rbuf = \$self->{rbuf};
1151		1182
1152	my $json = $self->{json} \|\|= JSON->new->utf8;	1183	my $json = $self->{json} \|\|= JSON->new->utf8;
1153		1184
1154	sub {	1185	sub {
1155	my $ref = $json->incr_parse ($self->{rbuf});	1186	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1156		1187
1157	if ($ref) {	1188	if ($ref) {
1158	$self->{rbuf} = $json->incr_text;	1189	$self->{rbuf} = $json->incr_text;
1159	$json->incr_text = "";	1190	$json->incr_text = "";
1160	$cb->($self, $ref);	1191	$cb->($self, $ref);
1161		1192
1162	1	1193	1
		1194	} elsif ($@) {
		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	()
1163	} else {	1204	} else {
1164	$self->{rbuf} = "";	1205	$self->{rbuf} = "";
		1206
1165	()	1207	()
1166	}	1208	}
1167	}	1209	}
1168	};	1210	};
1169		1211
…		…
1246	Note that AnyEvent::Handle will automatically C<start_read> for you when	1288	Note that AnyEvent::Handle will automatically C<start_read> for you when
1247	you change the C<on_read> callback or push/unshift a read callback, and it	1289	you change the C<on_read> callback or push/unshift a read callback, and it
1248	will automatically C<stop_read> for you when neither C<on_read> is set nor	1290	will automatically C<stop_read> for you when neither C<on_read> is set nor
1249	there are any read requests in the queue.	1291	there are any read requests in the queue.
1250		1292
		1293	These methods will have no effect when in TLS mode (as TLS doesn't support
		1294	half-duplex connections).
		1295
1251	=cut	1296	=cut
1252		1297
1253	sub stop_read {	1298	sub stop_read {
1254	my ($self) = @_;	1299	my ($self) = @_;
1255		1300
1256	delete $self->{_rw};	1301	delete $self->{_rw} unless $self->{tls};
1257	}	1302	}
1258		1303
1259	sub start_read {	1304	sub start_read {
1260	my ($self) = @_;	1305	my ($self) = @_;
1261		1306
1262	unless ($self->{_rw} \|\| $self->{_eof}) {	1307	unless ($self->{_rw} \|\| $self->{_eof}) {
1263	Scalar::Util::weaken $self;	1308	Scalar::Util::weaken $self;
1264		1309
1265	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1310	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1266	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1311	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1267	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;
1268		1313
1269	if ($len > 0) {	1314	if ($len > 0) {
1270	$self->{_activity} = AnyEvent->now;	1315	$self->{_activity} = AnyEvent->now;
1271		1316
1272	$self->{filter_r}	1317	if ($self->{tls}) {
1273	? $self->{filter_r}($self, $rbuf)	1318	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1274	: $self->{_in_drain} \|\| $self->_drain_rbuf;	1319
		1320	&_dotls ($self);
		1321	} else {
		1322	$self->_drain_rbuf unless $self->{_in_drain};
		1323	}
1275		1324
1276	} elsif (defined $len) {	1325	} elsif (defined $len) {
1277	delete $self->{_rw};	1326	delete $self->{_rw};
1278	$self->{_eof} = 1;	1327	$self->{_eof} = 1;
1279	$self->_drain_rbuf unless $self->{_in_drain};	1328	$self->_drain_rbuf unless $self->{_in_drain};
…		…
1283	}	1332	}
1284	});	1333	});
1285	}	1334	}
1286	}	1335	}
1287		1336
		1337	# poll the write BIO and send the data if applicable
1288	sub _dotls {	1338	sub _dotls {
1289	my ($self) = @_;	1339	my ($self) = @_;
1290		1340
1291	my $buf;	1341	my $tmp;
1292		1342
1293	if (length $self->{_tls_wbuf}) {	1343	if (length $self->{_tls_wbuf}) {
1294	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1344	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1295	substr $self->{_tls_wbuf}, 0, $len, "";	1345	substr $self->{_tls_wbuf}, 0, $tmp, "";
1296	}	1346	}
1297	}	1347	}
1298		1348
1299	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1300	$self->{wbuf} .= $buf;
1301	$self->_drain_wbuf;
1302	}
1303
1304	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1349	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1305	if (length $buf) {	1350	unless (length $tmp) {
1306	$self->{rbuf} .= $buf;
1307	$self->_drain_rbuf unless $self->{_in_drain};
1308	} else {
1309	# 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};
1310	$self->{_eof} = 1;	1353	$self->{_eof} = 1;
1311	$self->_shutdown;	1354	&_freetls;
1312	return;
1313	}	1355	}
1314	}
1315		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
1316	my $err = Net::SSLeay::get_error ($self->{tls}, -1);	1362	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1317		1363
1318	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {	1364	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1319	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {	1365	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1320	return $self->_error ($!, 1);	1366	return $self->_error ($!, 1);
1321	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1367	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1322	return $self->_error (&Errno::EIO, 1);	1368	return $self->_error (&Errno::EIO, 1);
1323	}	1369	}
1324		1370
1325	# all others are fine for our purposes	1371	# all other errors are fine for our purposes
		1372	}
		1373
		1374	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1375	$self->{wbuf} .= $tmp;
		1376	$self->_drain_wbuf;
1326	}	1377	}
1327	}	1378	}
1328		1379
1329	=item $handle->starttls ($tls[, $tls_ctx])	1380	=item $handle->starttls ($tls[, $tls_ctx])
1330		1381
…		…
1340		1391
1341	The TLS connection object will end up in C<< $handle->{tls} >> after this	1392	The TLS connection object will end up in C<< $handle->{tls} >> after this
1342	call and can be used or changed to your liking. Note that the handshake	1393	call and can be used or changed to your liking. Note that the handshake
1343	might have already started when this function returns.	1394	might have already started when this function returns.
1344		1395
		1396	If it an error to start a TLS handshake more than once per
		1397	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1398
1345	=cut	1399	=cut
1346		1400
1347	sub starttls {	1401	sub starttls {
1348	my ($self, $ssl, $ctx) = @_;	1402	my ($self, $ssl, $ctx) = @_;
1349		1403
1350	$self->stoptls;	1404	require Net::SSLeay;
1351		1405
		1406	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1407	if $self->{tls};
		1408
1352	if ($ssl eq "accept") {	1409	if ($ssl eq "accept") {
1353	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1410	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
1354	Net::SSLeay::set_accept_state ($ssl);	1411	Net::SSLeay::set_accept_state ($ssl);
1355	} elsif ($ssl eq "connect") {	1412	} elsif ($ssl eq "connect") {
1356	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1413	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
…		…
1362	# 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)
1363	# but the openssl maintainers basically said: "trust us, it just works".	1420	# but the openssl maintainers basically said: "trust us, it just works".
1364	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1421	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1365	# and mismaintained ssleay-module doesn't even offer them).	1422	# and mismaintained ssleay-module doesn't even offer them).
1366	# 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.
1367	Net::SSLeay::CTX_set_mode ($self->{tls},	1431	Net::SSLeay::CTX_set_mode ($self->{tls},
1368	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)	1432	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)
1369	\| (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));
1370		1434
1371	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1435	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1372	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1436	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1373		1437
1374	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1438	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1375		1439
1376	$self->{filter_w} = sub {	1440	&_dotls; # need to trigger the initial handshake
1377	$_[0]{_tls_wbuf} .= ${$_[1]};	1441	$self->start_read; # make sure we actually do read
1378	&_dotls;
1379	};
1380	$self->{filter_r} = sub {
1381	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1382	&_dotls;
1383	};
1384	}	1442	}
1385		1443
1386	=item $handle->stoptls	1444	=item $handle->stoptls
1387		1445
1388	Destroys the SSL connection, if any. Partial read or write data will be	1446	Shuts down the SSL connection - this makes a proper EOF handshake by
1389	lost.	1447	sending a close notify to the other side, but since OpenSSL doesn't
		1448	support non-blocking shut downs, it is not possible to re-use the stream
		1449	afterwards.
1390		1450
1391	=cut	1451	=cut
1392		1452
1393	sub stoptls {	1453	sub stoptls {
1394	my ($self) = @_;	1454	my ($self) = @_;
1395		1455
		1456	if ($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
1396	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1472	Net::SSLeay::free (delete $self->{tls});
1397		1473
1398	delete $self->{_rbio};	1474	delete @$self{qw(_rbio _wbio _tls_wbuf)};
1399	delete $self->{_wbio};
1400	delete $self->{_tls_wbuf};
1401	delete $self->{filter_r};
1402	delete $self->{filter_w};
1403	}	1475	}
1404		1476
1405	sub DESTROY {	1477	sub DESTROY {
1406	my $self = shift;	1478	my $self = shift;
1407		1479
1408	$self->stoptls;	1480	&_freetls;
1409		1481
1410	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	1482	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1411		1483
1412	if ($linger && length $self->{wbuf}) {	1484	if ($linger && length $self->{wbuf}) {
1413	my $fh = delete $self->{fh};	1485	my $fh = delete $self->{fh};
…		…
1428	@linger = ();	1500	@linger = ();
1429	});	1501	});
1430	}	1502	}
1431	}	1503	}
1432		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
1433	=item AnyEvent::Handle::TLS_CTX	1530	=item AnyEvent::Handle::TLS_CTX
1434		1531
1435	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
1436	default for TLS mode.	1533	default for TLS mode.
1437		1534
…		…
1465	}	1562	}
1466	}	1563	}
1467		1564
1468	=back	1565	=back
1469		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
1470	=head1 SUBCLASSING AnyEvent::Handle	1639	=head1 SUBCLASSING AnyEvent::Handle
1471		1640
1472	In many cases, you might want to subclass AnyEvent::Handle.	1641	In many cases, you might want to subclass AnyEvent::Handle.
1473		1642
1474	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

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.83 by root, Thu Aug 21 19:11:37 2008 UTC vs. Revision 1.118 by root, Thu Feb 12 17:33:38 2009 UTC

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.83 by root, Thu Aug 21 19:11:37 2008 UTC vs.
Revision 1.118 by root, Thu Feb 12 17:33:38 2009 UTC