ViewVC Help

View File | Revision Log | Show Annotations | Download File

/cvs/AnyEvent/lib/AnyEvent/Handle.pm

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.40 by root, Tue May 27 05:36:27 2008 UTC vs.
Revision 1.137 by root, Sat Jul 4 23:58:52 2009 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	no warnings;	3	no warnings;
4	use strict;	4	use strict qw(subs vars);
5		5
6	use AnyEvent ();	6	use AnyEvent ();
7	use AnyEvent::Util qw(WSAWOULDBLOCK);	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
10	use Fcntl ();	10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;	11	use Errno qw(EAGAIN EINTR);
12		12
13	=head1 NAME	13	=head1 NAME
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 = '0.04';	19	our $VERSION = 4.452;
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
…		…
60		63
61	=head1 METHODS	64	=head1 METHODS
62		65
63	=over 4	66	=over 4
64		67
65	=item B<new (%args)>	68	=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
66		69
67	The constructor supports these arguments (all as key => value pairs).	70	The constructor supports these arguments (all as C<< key => value >> pairs).
68		71
69	=over 4	72	=over 4
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 on EOF.	84	Set the callback to be called when an end-of-file condition is detected,
		85	i.e. in the case of a socket, when the other side has closed the
		86	connection cleanly.
81		87
		88	For sockets, this just means that the other side has stopped sending data,
		89	you can still try to write data, and, in fact, one can return from the EOF
		90	callback and continue writing data, as only the read part has been shut
		91	down.
		92
82	While not mandatory, it is highly recommended to set an eof callback,	93	While not mandatory, it is I<highly> recommended to set an EOF callback,
83	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
84	waiting for data.	95	waiting for data.
85		96
		97	If an EOF condition has been detected but no C<on_eof> callback has been
		98	set, then a fatal error will be raised with C<$!> set to <0>.
		99
86	=item on_error => $cb->($handle)	100	=item on_error => $cb->($handle, $fatal, $message)
87		101
88	This is the fatal error callback, that is called when, well, a fatal error	102	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	103	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	104	connect or a read error.
91		105
92	The object will not be in a usable state when this callback has been	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	107	fatal errors the handle object will be shut down and will not be usable
		108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		109	errors are an EOF condition with active (but unsatisifable) read watchers
		110	(C<EPIPE>) or I/O errors.
		111
		112	AnyEvent::Handle tries to find an appropriate error code for you to check
		113	against, but in some cases (TLS errors), this does not work well. It is
		114	recommended to always output the C<$message> argument in human-readable
		115	error messages (it's usually the same as C<"$!">).
		116
		117	Non-fatal errors can be retried by simply returning, but it is recommended
		118	to simply ignore this parameter and instead abondon the handle object
		119	when this callback is invoked. Examples of non-fatal errors are timeouts
		120	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
94		121
95	On callback entrance, the value of C<$!> contains the operating system	122	On callback entrance, the value of C<$!> contains the operating system
96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).	123	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
97		124	C<EPROTO>).
98	The callback should throw an exception. If it returns, then
99	AnyEvent::Handle will C<croak> for you.
100		125
101	While not mandatory, it is I<highly> recommended to set this callback, as	126	While not mandatory, it is I<highly> recommended to set this callback, as
102	you will not be notified of errors otherwise. The default simply calls	127	you will not be notified of errors otherwise. The default simply calls
103	die.	128	C<croak>.
104		129
105	=item on_read => $cb->($handle)	130	=item on_read => $cb->($handle)
106		131
107	This sets the default read callback, which is called when data arrives	132	This sets the default read callback, which is called when data arrives
108	and no read request is in the queue.	133	and no read request is in the queue (unlike read queue callbacks, this
		134	callback will only be called when at least one octet of data is in the
		135	read buffer).
109		136
110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	137	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111	method or access the C<$handle->{rbuf}> member directly.	138	method or access the C<$handle->{rbuf}> member directly. Note that you
		139	must not enlarge or modify the read buffer, you can only remove data at
		140	the beginning from it.
112		141
113	When an EOF condition is detected then AnyEvent::Handle will first try to	142	When an EOF condition is detected then AnyEvent::Handle will first try to
114	feed all the remaining data to the queued callbacks and C<on_read> before	143	feed all the remaining data to the queued callbacks and C<on_read> before
115	calling the C<on_eof> callback. If no progress can be made, then a fatal	144	calling the C<on_eof> callback. If no progress can be made, then a fatal
116	error will be raised (with C<$!> set to C<EPIPE>).	145	error will be raised (with C<$!> set to C<EPIPE>).
…		…
120	This sets the callback that is called when the write buffer becomes empty	149	This sets the callback that is called when the write buffer becomes empty
121	(or when the callback is set and the buffer is empty already).	150	(or when the callback is set and the buffer is empty already).
122		151
123	To append to the write buffer, use the C<< ->push_write >> method.	152	To append to the write buffer, use the C<< ->push_write >> method.
124		153
		154	This callback is useful when you don't want to put all of your write data
		155	into the queue at once, for example, when you want to write the contents
		156	of some file to the socket you might not want to read the whole file into
		157	memory and push it into the queue, but instead only read more data from
		158	the file when the write queue becomes empty.
		159
		160	=item timeout => $fractional_seconds
		161
		162	If non-zero, then this enables an "inactivity" timeout: whenever this many
		163	seconds pass without a successful read or write on the underlying file
		164	handle, the C<on_timeout> callback will be invoked (and if that one is
		165	missing, a non-fatal C<ETIMEDOUT> error will be raised).
		166
		167	Note that timeout processing is also active when you currently do not have
		168	any outstanding read or write requests: If you plan to keep the connection
		169	idle then you should disable the timout temporarily or ignore the timeout
		170	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		171	restart the timeout.
		172
		173	Zero (the default) disables this timeout.
		174
		175	=item on_timeout => $cb->($handle)
		176
		177	Called whenever the inactivity timeout passes. If you return from this
		178	callback, then the timeout will be reset as if some activity had happened,
		179	so this condition is not fatal in any way.
		180
125	=item rbuf_max => <bytes>	181	=item rbuf_max => <bytes>
126		182
127	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	183	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128	when the read buffer ever (strictly) exceeds this size. This is useful to	184	when the read buffer ever (strictly) exceeds this size. This is useful to
129	avoid denial-of-service attacks.	185	avoid some forms of denial-of-service attacks.
130		186
131	For example, a server accepting connections from untrusted sources should	187	For example, a server accepting connections from untrusted sources should
132	be configured to accept only so-and-so much data that it cannot act on	188	be configured to accept only so-and-so much data that it cannot act on
133	(for example, when expecting a line, an attacker could send an unlimited	189	(for example, when expecting a line, an attacker could send an unlimited
134	amount of data without a callback ever being called as long as the line	190	amount of data without a callback ever being called as long as the line
135	isn't finished).	191	isn't finished).
136		192
		193	=item autocork => <boolean>
		194
		195	When disabled (the default), then C<push_write> will try to immediately
		196	write the data to the handle, if possible. This avoids having to register
		197	a write watcher and wait for the next event loop iteration, but can
		198	be inefficient if you write multiple small chunks (on the wire, this
		199	disadvantage is usually avoided by your kernel's nagle algorithm, see
		200	C<no_delay>, but this option can save costly syscalls).
		201
		202	When enabled, then writes will always be queued till the next event loop
		203	iteration. This is efficient when you do many small writes per iteration,
		204	but less efficient when you do a single write only per iteration (or when
		205	the write buffer often is full). It also increases write latency.
		206
		207	=item no_delay => <boolean>
		208
		209	When doing small writes on sockets, your operating system kernel might
		210	wait a bit for more data before actually sending it out. This is called
		211	the Nagle algorithm, and usually it is beneficial.
		212
		213	In some situations you want as low a delay as possible, which can be
		214	accomplishd by setting this option to a true value.
		215
		216	The default is your opertaing system's default behaviour (most likely
		217	enabled), this option explicitly enables or disables it, if possible.
		218
137	=item read_size => <bytes>	219	=item read_size => <bytes>
138		220
139	The default read block size (the amount of bytes this module will try to read	221	The default read block size (the amount of bytes this module will
140	on each [loop iteration). Default: C<4096>.	222	try to read during each loop iteration, which affects memory
		223	requirements). Default: C<8192>.
141		224
142	=item low_water_mark => <bytes>	225	=item low_water_mark => <bytes>
143		226
144	Sets the amount of bytes (default: C<0>) that make up an "empty" write	227	Sets the amount of bytes (default: C<0>) that make up an "empty" write
145	buffer: If the write reaches this size or gets even samller it is	228	buffer: If the write reaches this size or gets even samller it is
146	considered empty.	229	considered empty.
147		230
		231	Sometimes it can be beneficial (for performance reasons) to add data to
		232	the write buffer before it is fully drained, but this is a rare case, as
		233	the operating system kernel usually buffers data as well, so the default
		234	is good in almost all cases.
		235
		236	=item linger => <seconds>
		237
		238	If non-zero (default: C<3600>), then the destructor of the
		239	AnyEvent::Handle object will check whether there is still outstanding
		240	write data and will install a watcher that will write this data to the
		241	socket. No errors will be reported (this mostly matches how the operating
		242	system treats outstanding data at socket close time).
		243
		244	This will not work for partial TLS data that could not be encoded
		245	yet. This data will be lost. Calling the C<stoptls> method in time might
		246	help.
		247
		248	=item peername => $string
		249
		250	A string used to identify the remote site - usually the DNS hostname
		251	(I<not> IDN!) used to create the connection, rarely the IP address.
		252
		253	Apart from being useful in error messages, this string is also used in TLS
		254	common name verification (see C<verify_cn> in L<AnyEvent::TLS>).
		255
148	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	256	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149		257
150	When this parameter is given, it enables TLS (SSL) mode, that means it	258	When this parameter is given, it enables TLS (SSL) mode, that means
151	will start making tls handshake and will transparently encrypt/decrypt	259	AnyEvent will start a TLS handshake as soon as the conenction has been
152	data.	260	established and will transparently encrypt/decrypt data afterwards.
		261
		262	All TLS protocol errors will be signalled as C<EPROTO>, with an
		263	appropriate error message.
153		264
154	TLS mode requires Net::SSLeay to be installed (it will be loaded	265	TLS mode requires Net::SSLeay to be installed (it will be loaded
155	automatically when you try to create a TLS handle).	266	automatically when you try to create a TLS handle): this module doesn't
		267	have a dependency on that module, so if your module requires it, you have
		268	to add the dependency yourself.
156		269
157	For the TLS server side, use C<accept>, and for the TLS client side of a	270	Unlike TCP, TLS has a server and client side: for the TLS server side, use
158	connection, use C<connect> mode.	271	C<accept>, and for the TLS client side of a connection, use C<connect>
		272	mode.
159		273
160	You can also provide your own TLS connection object, but you have	274	You can also provide your own TLS connection object, but you have
161	to make sure that you call either C<Net::SSLeay::set_connect_state>	275	to make sure that you call either C<Net::SSLeay::set_connect_state>
162	or C<Net::SSLeay::set_accept_state> on it before you pass it to	276	or C<Net::SSLeay::set_accept_state> on it before you pass it to
163	AnyEvent::Handle.	277	AnyEvent::Handle. Also, this module will take ownership of this connection
		278	object.
164		279
		280	At some future point, AnyEvent::Handle might switch to another TLS
		281	implementation, then the option to use your own session object will go
		282	away.
		283
		284	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		285	passing in the wrong integer will lead to certain crash. This most often
		286	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		287	segmentation fault.
		288
165	See the C<starttls> method if you need to start TLs negotiation later.	289	See the C<< ->starttls >> method for when need to start TLS negotiation later.
166		290
167	=item tls_ctx => $ssl_ctx	291	=item tls_ctx => $anyevent_tls
168		292
169	Use the given Net::SSLeay::CTX object to create the new TLS connection	293	Use the given C<AnyEvent::TLS> object to create the new TLS connection
170	(unless a connection object was specified directly). If this parameter is	294	(unless a connection object was specified directly). If this parameter is
171	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	295	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172		296
		297	Instead of an object, you can also specify a hash reference with C<< key
		298	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		299	new TLS context object.
		300
173	=item json => JSON or JSON::XS object	301	=item json => JSON or JSON::XS object
174		302
175	This is the json coder object used by the C<json> read and write types.	303	This is the json coder object used by the C<json> read and write types.
176		304
177	If you don't supply it, then AnyEvent::Handle will use C<encode_json> and	305	If you don't supply it, then AnyEvent::Handle will create and use a
178	C<decode_json>.	306	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		307	texts.
179		308
180	Note that you are responsible to depend on the JSON module if you want to	309	Note that you are responsible to depend on the JSON module if you want to
181	use this functionality, as AnyEvent does not have a dependency itself.	310	use this functionality, as AnyEvent does not have a dependency itself.
182		311
183	=item filter_r => $cb
184
185	=item filter_w => $cb
186
187	These exist, but are undocumented at this time.
188
189	=back	312	=back
190		313
191	=cut	314	=cut
192		315
193	sub new {	316	sub new {
194	my $class = shift;	317	my $class = shift;
195
196	my $self = bless { @_ }, $class;	318	my $self = bless { @_ }, $class;
197		319
198	$self->{fh} or Carp::croak "mandatory argument fh is missing";	320	$self->{fh} or Carp::croak "mandatory argument fh is missing";
199		321
200	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	322	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
201		323
202	if ($self->{tls}) {	324	$self->{_activity} = AnyEvent->now;
203	require Net::SSLeay;	325	$self->_timeout;
		326
		327	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
		328
204	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	329	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
205	}	330	if $self->{tls};
206		331
207	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
208	$self->on_error (delete $self->{on_error}) if $self->{on_error};
209	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	332	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
210	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
211		333
212	$self->start_read;	334	$self->start_read
		335	if $self->{on_read};
213		336
214	$self	337	$self->{fh} && $self
215	}	338	}
216		339
217	sub _shutdown {	340	sub _shutdown {
218	my ($self) = @_;	341	my ($self) = @_;
219		342
220	delete $self->{_rw};	343	delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
221	delete $self->{_ww};	344	$self->{_eof} = 1; # tell starttls et. al to stop trying
222	delete $self->{fh};
223	}
224		345
		346	&_freetls;
		347	}
		348
225	sub error {	349	sub _error {
226	my ($self) = @_;	350	my ($self, $errno, $fatal, $message) = @_;
227		351
228	{
229	local $!;
230	$self->_shutdown;	352	$self->_shutdown
231	}	353	if $fatal;
232		354
233	$self->{on_error}($self)	355	$! = $errno;
		356	$message ||= "$!";
		357
234	if $self->{on_error};	358	if ($self->{on_error}) {
235		359	$self->{on_error}($self, $fatal, $message);
		360	} elsif ($self->{fh}) {
236	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	361	Carp::croak "AnyEvent::Handle uncaught error: $message";
		362	}
237	}	363	}
238		364
239	=item $fh = $handle->fh	365	=item $fh = $handle->fh
240		366
241	This method returns the file handle of the L<AnyEvent::Handle> object.	367	This method returns the file handle used to create the L<AnyEvent::Handle> object.
242		368
243	=cut	369	=cut
244		370
245	sub fh { $_[0]{fh} }	371	sub fh { $_[0]{fh} }
246		372
…		…
262		388
263	sub on_eof {	389	sub on_eof {
264	$_[0]{on_eof} = $_[1];	390	$_[0]{on_eof} = $_[1];
265	}	391	}
266		392
		393	=item $handle->on_timeout ($cb)
		394
		395	Replace the current C<on_timeout> callback, or disables the callback (but
		396	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
		397	argument and method.
		398
		399	=cut
		400
		401	sub on_timeout {
		402	$_[0]{on_timeout} = $_[1];
		403	}
		404
		405	=item $handle->autocork ($boolean)
		406
		407	Enables or disables the current autocork behaviour (see C<autocork>
		408	constructor argument). Changes will only take effect on the next write.
		409
		410	=cut
		411
		412	sub autocork {
		413	$_[0]{autocork} = $_[1];
		414	}
		415
		416	=item $handle->no_delay ($boolean)
		417
		418	Enables or disables the C<no_delay> setting (see constructor argument of
		419	the same name for details).
		420
		421	=cut
		422
		423	sub no_delay {
		424	$_[0]{no_delay} = $_[1];
		425
		426	eval {
		427	local $SIG{__DIE__};
		428	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		429	};
		430	}
		431
		432	#############################################################################
		433
		434	=item $handle->timeout ($seconds)
		435
		436	Configures (or disables) the inactivity timeout.
		437
		438	=cut
		439
		440	sub timeout {
		441	my ($self, $timeout) = @_;
		442
		443	$self->{timeout} = $timeout;
		444	$self->_timeout;
		445	}
		446
		447	# reset the timeout watcher, as neccessary
		448	# also check for time-outs
		449	sub _timeout {
		450	my ($self) = @_;
		451
		452	if ($self->{timeout}) {
		453	my $NOW = AnyEvent->now;
		454
		455	# when would the timeout trigger?
		456	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		457
		458	# now or in the past already?
		459	if ($after <= 0) {
		460	$self->{_activity} = $NOW;
		461
		462	if ($self->{on_timeout}) {
		463	$self->{on_timeout}($self);
		464	} else {
		465	$self->_error (&Errno::ETIMEDOUT);
		466	}
		467
		468	# callback could have changed timeout value, optimise
		469	return unless $self->{timeout};
		470
		471	# calculate new after
		472	$after = $self->{timeout};
		473	}
		474
		475	Scalar::Util::weaken $self;
		476	return unless $self; # ->error could have destroyed $self
		477
		478	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		479	delete $self->{_tw};
		480	$self->_timeout;
		481	});
		482	} else {
		483	delete $self->{_tw};
		484	}
		485	}
		486
267	#############################################################################	487	#############################################################################
268		488
269	=back	489	=back
270		490
271	=head2 WRITE QUEUE	491	=head2 WRITE QUEUE
…		…
292	my ($self, $cb) = @_;	512	my ($self, $cb) = @_;
293		513
294	$self->{on_drain} = $cb;	514	$self->{on_drain} = $cb;
295		515
296	$cb->($self)	516	$cb->($self)
297	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	517	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
298	}	518	}
299		519
300	=item $handle->push_write ($data)	520	=item $handle->push_write ($data)
301		521
302	Queues the given scalar to be written. You can push as much data as you	522	Queues the given scalar to be written. You can push as much data as you
…		…
316	my $len = syswrite $self->{fh}, $self->{wbuf};	536	my $len = syswrite $self->{fh}, $self->{wbuf};
317		537
318	if ($len >= 0) {	538	if ($len >= 0) {
319	substr $self->{wbuf}, 0, $len, "";	539	substr $self->{wbuf}, 0, $len, "";
320		540
		541	$self->{_activity} = AnyEvent->now;
		542
321	$self->{on_drain}($self)	543	$self->{on_drain}($self)
322	if $self->{low_water_mark} >= length $self->{wbuf}	544	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
323	&& $self->{on_drain};	545	&& $self->{on_drain};
324		546
325	delete $self->{_ww} unless length $self->{wbuf};	547	delete $self->{_ww} unless length $self->{wbuf};
326	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) {	548	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
327	$self->error;	549	$self->_error ($!, 1);
328	}	550	}
329	};	551	};
330		552
331	# try to write data immediately	553	# try to write data immediately
332	$cb->();	554	$cb->() unless $self->{autocork};
333		555
334	# if still data left in wbuf, we need to poll	556	# if still data left in wbuf, we need to poll
335	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	557	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
336	if length $self->{wbuf};	558	if length $self->{wbuf};
337	};	559	};
…		…
351		573
352	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	574	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
353	->($self, @_);	575	->($self, @_);
354	}	576	}
355		577
356	if ($self->{filter_w}) {	578	if ($self->{tls}) {
357	$self->{filter_w}->($self, \$_[0]);	579	$self->{_tls_wbuf} .= $_[0];
		580
		581	&_dotls ($self);
358	} else {	582	} else {
359	$self->{wbuf} .= $_[0];	583	$self->{wbuf} .= $_[0];
360	$self->_drain_wbuf;	584	$self->_drain_wbuf;
361	}	585	}
362	}	586	}
363		587
364	=item $handle->push_write (type => @args)	588	=item $handle->push_write (type => @args)
365		589
366	=item $handle->unshift_write (type => @args)
367
368	Instead of formatting your data yourself, you can also let this module do	590	Instead of formatting your data yourself, you can also let this module do
369	the job by specifying a type and type-specific arguments.	591	the job by specifying a type and type-specific arguments.
370		592
371	Predefined types are (if you have ideas for additional types, feel free to	593	Predefined types are (if you have ideas for additional types, feel free to
372	drop by and tell us):	594	drop by and tell us):
…		…
376	=item netstring => $string	598	=item netstring => $string
377		599
378	Formats the given value as netstring	600	Formats the given value as netstring
379	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	601	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
380		602
381	=back
382
383	=cut	603	=cut
384		604
385	register_write_type netstring => sub {	605	register_write_type netstring => sub {
386	my ($self, $string) = @_;	606	my ($self, $string) = @_;
387		607
388	sprintf "%d:%s,", (length $string), $string	608	(length $string) . ":$string,"
		609	};
		610
		611	=item packstring => $format, $data
		612
		613	An octet string prefixed with an encoded length. The encoding C<$format>
		614	uses the same format as a Perl C<pack> format, but must specify a single
		615	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		616	optional C<!>, C<< < >> or C<< > >> modifier).
		617
		618	=cut
		619
		620	register_write_type packstring => sub {
		621	my ($self, $format, $string) = @_;
		622
		623	pack "$format/a*", $string
389	};	624	};
390		625
391	=item json => $array_or_hashref	626	=item json => $array_or_hashref
392		627
393	Encodes the given hash or array reference into a JSON object. Unless you	628	Encodes the given hash or array reference into a JSON object. Unless you
…		…
396		631
397	JSON objects (and arrays) are self-delimiting, so you can write JSON at	632	JSON objects (and arrays) are self-delimiting, so you can write JSON at
398	one end of a handle and read them at the other end without using any	633	one end of a handle and read them at the other end without using any
399	additional framing.	634	additional framing.
400		635
		636	The generated JSON text is guaranteed not to contain any newlines: While
		637	this module doesn't need delimiters after or between JSON texts to be
		638	able to read them, many other languages depend on that.
		639
		640	A simple RPC protocol that interoperates easily with others is to send
		641	JSON arrays (or objects, although arrays are usually the better choice as
		642	they mimic how function argument passing works) and a newline after each
		643	JSON text:
		644
		645	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		646	$handle->push_write ("\012");
		647
		648	An AnyEvent::Handle receiver would simply use the C<json> read type and
		649	rely on the fact that the newline will be skipped as leading whitespace:
		650
		651	$handle->push_read (json => sub { my $array = $_[1]; ... });
		652
		653	Other languages could read single lines terminated by a newline and pass
		654	this line into their JSON decoder of choice.
		655
401	=cut	656	=cut
402		657
403	register_write_type json => sub {	658	register_write_type json => sub {
404	my ($self, $ref) = @_;	659	my ($self, $ref) = @_;
405		660
…		…
407		662
408	$self->{json} ? $self->{json}->encode ($ref)	663	$self->{json} ? $self->{json}->encode ($ref)
409	: JSON::encode_json ($ref)	664	: JSON::encode_json ($ref)
410	};	665	};
411		666
		667	=item storable => $reference
		668
		669	Freezes the given reference using L<Storable> and writes it to the
		670	handle. Uses the C<nfreeze> format.
		671
		672	=cut
		673
		674	register_write_type storable => sub {
		675	my ($self, $ref) = @_;
		676
		677	require Storable;
		678
		679	pack "w/a*", Storable::nfreeze ($ref)
		680	};
		681
		682	=back
		683
		684	=item $handle->push_shutdown
		685
		686	Sometimes you know you want to close the socket after writing your data
		687	before it was actually written. One way to do that is to replace your
		688	C<on_drain> handler by a callback that shuts down the socket. This method
		689	is a shorthand for just that, and replaces the C<on_drain> callback with:
		690
		691	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		692
		693	This simply shuts down the write side and signals an EOF condition to the
		694	the peer.
		695
		696	You can rely on the normal read queue and C<on_eof> handling
		697	afterwards. This is the cleanest way to close a connection.
		698
		699	=cut
		700
		701	sub push_shutdown {
		702	$_[0]->{on_drain} = sub { shutdown $_[0]{fh}, 1 };
		703	}
		704
412	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	705	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
413		706
414	This function (not method) lets you add your own types to C<push_write>.	707	This function (not method) lets you add your own types to C<push_write>.
415	Whenever the given C<type> is used, C<push_write> will invoke the code	708	Whenever the given C<type> is used, C<push_write> will invoke the code
416	reference with the handle object and the remaining arguments.	709	reference with the handle object and the remaining arguments.
…		…
436	ways, the "simple" way, using only C<on_read> and the "complex" way, using	729	ways, the "simple" way, using only C<on_read> and the "complex" way, using
437	a queue.	730	a queue.
438		731
439	In the simple case, you just install an C<on_read> callback and whenever	732	In the simple case, you just install an C<on_read> callback and whenever
440	new data arrives, it will be called. You can then remove some data (if	733	new data arrives, it will be called. You can then remove some data (if
441	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	734	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
442	or not.	735	leave the data there if you want to accumulate more (e.g. when only a
		736	partial message has been received so far).
443		737
444	In the more complex case, you want to queue multiple callbacks. In this	738	In the more complex case, you want to queue multiple callbacks. In this
445	case, AnyEvent::Handle will call the first queued callback each time new	739	case, AnyEvent::Handle will call the first queued callback each time new
446	data arrives and removes it when it has done its job (see C<push_read>,	740	data arrives (also the first time it is queued) and removes it when it has
447	below).	741	done its job (see C<push_read>, below).
448		742
449	This way you can, for example, push three line-reads, followed by reading	743	This way you can, for example, push three line-reads, followed by reading
450	a chunk of data, and AnyEvent::Handle will execute them in order.	744	a chunk of data, and AnyEvent::Handle will execute them in order.
451		745
452	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	746	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
453	the specified number of bytes which give an XML datagram.	747	the specified number of bytes which give an XML datagram.
454		748
455	# in the default state, expect some header bytes	749	# in the default state, expect some header bytes
456	$handle->on_read (sub {	750	$handle->on_read (sub {
457	# some data is here, now queue the length-header-read (4 octets)	751	# some data is here, now queue the length-header-read (4 octets)
458	shift->unshift_read_chunk (4, sub {	752	shift->unshift_read (chunk => 4, sub {
459	# header arrived, decode	753	# header arrived, decode
460	my $len = unpack "N", $_[1];	754	my $len = unpack "N", $_[1];
461		755
462	# now read the payload	756	# now read the payload
463	shift->unshift_read_chunk ($len, sub {	757	shift->unshift_read (chunk => $len, sub {
464	my $xml = $_[1];	758	my $xml = $_[1];
465	# handle xml	759	# handle xml
466	});	760	});
467	});	761	});
468	});	762	});
469		763
470	Example 2: Implement a client for a protocol that replies either with	764	Example 2: Implement a client for a protocol that replies either with "OK"
471	"OK" and another line or "ERROR" for one request, and 64 bytes for the	765	and another line or "ERROR" for the first request that is sent, and 64
472	second request. Due tot he availability of a full queue, we can just	766	bytes for the second request. Due to the availability of a queue, we can
473	pipeline sending both requests and manipulate the queue as necessary in	767	just pipeline sending both requests and manipulate the queue as necessary
474	the callbacks:	768	in the callbacks.
475		769
476	# request one	770	When the first callback is called and sees an "OK" response, it will
		771	C<unshift> another line-read. This line-read will be queued I<before> the
		772	64-byte chunk callback.
		773
		774	# request one, returns either "OK + extra line" or "ERROR"
477	$handle->push_write ("request 1\015\012");	775	$handle->push_write ("request 1\015\012");
478		776
479	# we expect "ERROR" or "OK" as response, so push a line read	777	# we expect "ERROR" or "OK" as response, so push a line read
480	$handle->push_read_line (sub {	778	$handle->push_read (line => sub {
481	# if we got an "OK", we have to _prepend_ another line,	779	# if we got an "OK", we have to _prepend_ another line,
482	# so it will be read before the second request reads its 64 bytes	780	# so it will be read before the second request reads its 64 bytes
483	# which are already in the queue when this callback is called	781	# which are already in the queue when this callback is called
484	# we don't do this in case we got an error	782	# we don't do this in case we got an error
485	if ($_[1] eq "OK") {	783	if ($_[1] eq "OK") {
486	$_[0]->unshift_read_line (sub {	784	$_[0]->unshift_read (line => sub {
487	my $response = $_[1];	785	my $response = $_[1];
488	...	786	...
489	});	787	});
490	}	788	}
491	});	789	});
492		790
493	# request two	791	# request two, simply returns 64 octets
494	$handle->push_write ("request 2\015\012");	792	$handle->push_write ("request 2\015\012");
495		793
496	# simply read 64 bytes, always	794	# simply read 64 bytes, always
497	$handle->push_read_chunk (64, sub {	795	$handle->push_read (chunk => 64, sub {
498	my $response = $_[1];	796	my $response = $_[1];
499	...	797	...
500	});	798	});
501		799
502	=over 4	800	=over 4
503		801
504	=cut	802	=cut
505		803
506	sub _drain_rbuf {	804	sub _drain_rbuf {
507	my ($self) = @_;	805	my ($self) = @_;
		806
		807	local $self->{_in_drain} = 1;
508		808
509	if (	809	if (
510	defined $self->{rbuf_max}	810	defined $self->{rbuf_max}
511	&& $self->{rbuf_max} < length $self->{rbuf}	811	&& $self->{rbuf_max} < length $self->{rbuf}
512	) {	812	) {
513	$! = &Errno::ENOSPC;	813	$self->_error (&Errno::ENOSPC, 1), return;
514	$self->error;
515	}	814	}
516		815
517	return if $self->{in_drain};	816	while () {
518	local $self->{in_drain} = 1;	817	# we need to use a separate tls read buffer, as we must not receive data while
		818	# we are draining the buffer, and this can only happen with TLS.
		819	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
519		820
520	while (my $len = length $self->{rbuf}) {	821	my $len = length $self->{rbuf};
521	no strict 'refs';	822
522	if (my $cb = shift @{ $self->{_queue} }) {	823	if (my $cb = shift @{ $self->{_queue} }) {
523	unless ($cb->($self)) {	824	unless ($cb->($self)) {
524	if ($self->{_eof}) {	825	if ($self->{_eof}) {
525	# no progress can be made (not enough data and no data forthcoming)	826	# no progress can be made (not enough data and no data forthcoming)
526	$! = &Errno::EPIPE;	827	$self->_error (&Errno::EPIPE, 1), return;
527	$self->error;
528	}	828	}
529		829
530	unshift @{ $self->{_queue} }, $cb;	830	unshift @{ $self->{_queue} }, $cb;
531	return;	831	last;
532	}	832	}
533	} elsif ($self->{on_read}) {	833	} elsif ($self->{on_read}) {
		834	last unless $len;
		835
534	$self->{on_read}($self);	836	$self->{on_read}($self);
535		837
536	if (	838	if (
537	$self->{_eof} # if no further data will arrive
538	&& $len == length $self->{rbuf} # and no data has been consumed	839	$len == length $self->{rbuf} # if no data has been consumed
539	&& !@{ $self->{_queue} } # and the queue is still empty	840	&& !@{ $self->{_queue} } # and the queue is still empty
540	&& $self->{on_read} # and we still want to read data	841	&& $self->{on_read} # but we still have on_read
541	) {	842	) {
		843	# no further data will arrive
542	# then no progress can be made	844	# so no progress can be made
543	$! = &Errno::EPIPE;	845	$self->_error (&Errno::EPIPE, 1), return
544	$self->error;	846	if $self->{_eof};
		847
		848	last; # more data might arrive
545	}	849	}
546	} else {	850	} else {
547	# read side becomes idle	851	# read side becomes idle
548	delete $self->{_rw};	852	delete $self->{_rw} unless $self->{tls};
549	return;	853	last;
550	}	854	}
551	}	855	}
552		856
553	if ($self->{_eof}) {	857	if ($self->{_eof}) {
554	$self->_shutdown;	858	if ($self->{on_eof}) {
555	$self->{on_eof}($self)	859	$self->{on_eof}($self)
556	if $self->{on_eof};	860	} else {
		861	$self->_error (0, 1);
		862	}
		863	}
		864
		865	# may need to restart read watcher
		866	unless ($self->{_rw}) {
		867	$self->start_read
		868	if $self->{on_read} || @{ $self->{_queue} };
557	}	869	}
558	}	870	}
559		871
560	=item $handle->on_read ($cb)	872	=item $handle->on_read ($cb)
561		873
…		…
567		879
568	sub on_read {	880	sub on_read {
569	my ($self, $cb) = @_;	881	my ($self, $cb) = @_;
570		882
571	$self->{on_read} = $cb;	883	$self->{on_read} = $cb;
		884	$self->_drain_rbuf if $cb && !$self->{_in_drain};
572	}	885	}
573		886
574	=item $handle->rbuf	887	=item $handle->rbuf
575		888
576	Returns the read buffer (as a modifiable lvalue).	889	Returns the read buffer (as a modifiable lvalue).
577		890
578	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	891	You can access the read buffer directly as the C<< ->{rbuf} >>
579	you want.	892	member, if you want. However, the only operation allowed on the
		893	read buffer (apart from looking at it) is removing data from its
		894	beginning. Otherwise modifying or appending to it is not allowed and will
		895	lead to hard-to-track-down bugs.
580		896
581	NOTE: The read buffer should only be used or modified if the C<on_read>,	897	NOTE: The read buffer should only be used or modified if the C<on_read>,
582	C<push_read> or C<unshift_read> methods are used. The other read methods	898	C<push_read> or C<unshift_read> methods are used. The other read methods
583	automatically manage the read buffer.	899	automatically manage the read buffer.
584		900
…		…
625	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	941	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
626	->($self, $cb, @_);	942	->($self, $cb, @_);
627	}	943	}
628		944
629	push @{ $self->{_queue} }, $cb;	945	push @{ $self->{_queue} }, $cb;
630	$self->_drain_rbuf;	946	$self->_drain_rbuf unless $self->{_in_drain};
631	}	947	}
632		948
633	sub unshift_read {	949	sub unshift_read {
634	my $self = shift;	950	my $self = shift;
635	my $cb = pop;	951	my $cb = pop;
…		…
641	->($self, $cb, @_);	957	->($self, $cb, @_);
642	}	958	}
643		959
644		960
645	unshift @{ $self->{_queue} }, $cb;	961	unshift @{ $self->{_queue} }, $cb;
646	$self->_drain_rbuf;	962	$self->_drain_rbuf unless $self->{_in_drain};
647	}	963	}
648		964
649	=item $handle->push_read (type => @args, $cb)	965	=item $handle->push_read (type => @args, $cb)
650		966
651	=item $handle->unshift_read (type => @args, $cb)	967	=item $handle->unshift_read (type => @args, $cb)
…		…
681	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	997	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
682	1	998	1
683	}	999	}
684	};	1000	};
685		1001
686	# compatibility with older API
687	sub push_read_chunk {
688	$_[0]->push_read (chunk => $_[1], $_[2]);
689	}
690
691	sub unshift_read_chunk {
692	$_[0]->unshift_read (chunk => $_[1], $_[2]);
693	}
694
695	=item line => [$eol, ]$cb->($handle, $line, $eol)	1002	=item line => [$eol, ]$cb->($handle, $line, $eol)
696		1003
697	The callback will be called only once a full line (including the end of	1004	The callback will be called only once a full line (including the end of
698	line marker, C<$eol>) has been read. This line (excluding the end of line	1005	line marker, C<$eol>) has been read. This line (excluding the end of line
699	marker) will be passed to the callback as second argument (C<$line>), and	1006	marker) will be passed to the callback as second argument (C<$line>), and
…		…
714	=cut	1021	=cut
715		1022
716	register_read_type line => sub {	1023	register_read_type line => sub {
717	my ($self, $cb, $eol) = @_;	1024	my ($self, $cb, $eol) = @_;
718		1025
719	$eol = qr|(\015?\012)| if @_ < 3;	1026	if (@_ < 3) {
720	$eol = quotemeta $eol unless ref $eol;	1027	# this is more than twice as fast as the generic code below
721	$eol = qr|^(.*?)($eol)|s;
722
723	sub {	1028	sub {
724	$_[0]{rbuf} =~ s/$eol// or return;	1029	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
725		1030
726	$cb->($_[0], $1, $2);	1031	$cb->($_[0], $1, $2);
727	1
728	}
729	};
730
731	# compatibility with older API
732	sub push_read_line {
733	my $self = shift;
734	$self->push_read (line => @_);
735	}
736
737	sub unshift_read_line {
738	my $self = shift;
739	$self->unshift_read (line => @_);
740	}
741
742	=item netstring => $cb->($handle, $string)
743
744	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
745
746	Throws an error with C<$!> set to EBADMSG on format violations.
747
748	=cut
749
750	register_read_type netstring => sub {
751	my ($self, $cb) = @_;
752
753	sub {
754	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
755	if ($_[0]{rbuf} =~ /[^0-9]/) {
756	$! = &Errno::EBADMSG;
757	$self->error;
758	}	1032	1
759	return;
760	}	1033	}
		1034	} else {
		1035	$eol = quotemeta $eol unless ref $eol;
		1036	$eol = qr|^(.*?)($eol)|s;
761		1037
762	my $len = $1;	1038	sub {
		1039	$_[0]{rbuf} =~ s/$eol// or return;
763		1040
764	$self->unshift_read (chunk => $len, sub {	1041	$cb->($_[0], $1, $2);
765	my $string = $_[1];
766	$_[0]->unshift_read (chunk => 1, sub {
767	if ($_[1] eq ",") {
768	$cb->($_[0], $string);
769	} else {
770	$! = &Errno::EBADMSG;
771	$self->error;
772	}
773	});	1042	1
774	});	1043	}
775
776	1
777	}	1044	}
778	};	1045	};
779		1046
780	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)	1047	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
781		1048
…		…
833	return 1;	1100	return 1;
834	}	1101	}
835		1102
836	# reject	1103	# reject
837	if ($reject && $$rbuf =~ $reject) {	1104	if ($reject && $$rbuf =~ $reject) {
838	$! = &Errno::EBADMSG;	1105	$self->_error (&Errno::EBADMSG);
839	$self->error;
840	}	1106	}
841		1107
842	# skip	1108	# skip
843	if ($skip && $$rbuf =~ $skip) {	1109	if ($skip && $$rbuf =~ $skip) {
844	$data .= substr $$rbuf, 0, $+[0], "";	1110	$data .= substr $$rbuf, 0, $+[0], "";
…		…
846		1112
847	()	1113	()
848	}	1114	}
849	};	1115	};
850		1116
		1117	=item netstring => $cb->($handle, $string)
		1118
		1119	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1120
		1121	Throws an error with C<$!> set to EBADMSG on format violations.
		1122
		1123	=cut
		1124
		1125	register_read_type netstring => sub {
		1126	my ($self, $cb) = @_;
		1127
		1128	sub {
		1129	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1130	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1131	$self->_error (&Errno::EBADMSG);
		1132	}
		1133	return;
		1134	}
		1135
		1136	my $len = $1;
		1137
		1138	$self->unshift_read (chunk => $len, sub {
		1139	my $string = $_[1];
		1140	$_[0]->unshift_read (chunk => 1, sub {
		1141	if ($_[1] eq ",") {
		1142	$cb->($_[0], $string);
		1143	} else {
		1144	$self->_error (&Errno::EBADMSG);
		1145	}
		1146	});
		1147	});
		1148
		1149	1
		1150	}
		1151	};
		1152
		1153	=item packstring => $format, $cb->($handle, $string)
		1154
		1155	An octet string prefixed with an encoded length. The encoding C<$format>
		1156	uses the same format as a Perl C<pack> format, but must specify a single
		1157	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1158	optional C<!>, C<< < >> or C<< > >> modifier).
		1159
		1160	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1161	EPP uses a prefix of C<N> (4 octtes).
		1162
		1163	Example: read a block of data prefixed by its length in BER-encoded
		1164	format (very efficient).
		1165
		1166	$handle->push_read (packstring => "w", sub {
		1167	my ($handle, $data) = @_;
		1168	});
		1169
		1170	=cut
		1171
		1172	register_read_type packstring => sub {
		1173	my ($self, $cb, $format) = @_;
		1174
		1175	sub {
		1176	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1177	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1178	or return;
		1179
		1180	$format = length pack $format, $len;
		1181
		1182	# bypass unshift if we already have the remaining chunk
		1183	if ($format + $len <= length $_[0]{rbuf}) {
		1184	my $data = substr $_[0]{rbuf}, $format, $len;
		1185	substr $_[0]{rbuf}, 0, $format + $len, "";
		1186	$cb->($_[0], $data);
		1187	} else {
		1188	# remove prefix
		1189	substr $_[0]{rbuf}, 0, $format, "";
		1190
		1191	# read remaining chunk
		1192	$_[0]->unshift_read (chunk => $len, $cb);
		1193	}
		1194
		1195	1
		1196	}
		1197	};
		1198
851	=item json => $cb->($handle, $hash_or_arrayref)	1199	=item json => $cb->($handle, $hash_or_arrayref)
852		1200
853	Reads a JSON object or array, decodes it and passes it to the callback.	1201	Reads a JSON object or array, decodes it and passes it to the
		1202	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
854		1203
855	If a C<json> object was passed to the constructor, then that will be used	1204	If a C<json> object was passed to the constructor, then that will be used
856	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1205	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
857		1206
858	This read type uses the incremental parser available with JSON version	1207	This read type uses the incremental parser available with JSON version
859	2.09 (and JSON::XS version 2.2) and above. You have to provide a	1208	2.09 (and JSON::XS version 2.2) and above. You have to provide a
860	dependency on your own: this module will load the JSON module, but	1209	dependency on your own: this module will load the JSON module, but
861	AnyEvent does not depend on it itself.	1210	AnyEvent does not depend on it itself.
862		1211
863	Since JSON texts are fully self-delimiting, the C<json> read and write	1212	Since JSON texts are fully self-delimiting, the C<json> read and write
864	types are an ideal simple RPC protocol: just exchange JSON datagrams.	1213	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1214	the C<json> write type description, above, for an actual example.
865		1215
866	=cut	1216	=cut
867		1217
868	register_read_type json => sub {	1218	register_read_type json => sub {
869	my ($self, $cb, $accept, $reject, $skip) = @_;	1219	my ($self, $cb) = @_;
870		1220
871	require JSON;	1221	my $json = $self->{json} ||=
		1222	eval { require JSON::XS; JSON::XS->new->utf8 }
		1223	|| do { require JSON; JSON->new->utf8 };
872		1224
873	my $data;	1225	my $data;
874	my $rbuf = \$self->{rbuf};	1226	my $rbuf = \$self->{rbuf};
875		1227
876	my $json = $self->{json} ||= JSON::XS->new->utf8;
877
878	sub {	1228	sub {
879	my $ref = $json->incr_parse ($self->{rbuf});	1229	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
880		1230
881	if ($ref) {	1231	if ($ref) {
882	$self->{rbuf} = $json->incr_text;	1232	$self->{rbuf} = $json->incr_text;
883	$json->incr_text = "";	1233	$json->incr_text = "";
884	$cb->($self, $ref);	1234	$cb->($self, $ref);
885		1235
886	1	1236	1
		1237	} elsif ($@) {
		1238	# error case
		1239	$json->incr_skip;
		1240
		1241	$self->{rbuf} = $json->incr_text;
		1242	$json->incr_text = "";
		1243
		1244	$self->_error (&Errno::EBADMSG);
		1245
		1246	()
887	} else {	1247	} else {
888	$self->{rbuf} = "";	1248	$self->{rbuf} = "";
		1249
889	()	1250	()
890	}	1251	}
		1252	}
		1253	};
		1254
		1255	=item storable => $cb->($handle, $ref)
		1256
		1257	Deserialises a L<Storable> frozen representation as written by the
		1258	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1259	data).
		1260
		1261	Raises C<EBADMSG> error if the data could not be decoded.
		1262
		1263	=cut
		1264
		1265	register_read_type storable => sub {
		1266	my ($self, $cb) = @_;
		1267
		1268	require Storable;
		1269
		1270	sub {
		1271	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1272	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1273	or return;
		1274
		1275	my $format = length pack "w", $len;
		1276
		1277	# bypass unshift if we already have the remaining chunk
		1278	if ($format + $len <= length $_[0]{rbuf}) {
		1279	my $data = substr $_[0]{rbuf}, $format, $len;
		1280	substr $_[0]{rbuf}, 0, $format + $len, "";
		1281	$cb->($_[0], Storable::thaw ($data));
		1282	} else {
		1283	# remove prefix
		1284	substr $_[0]{rbuf}, 0, $format, "";
		1285
		1286	# read remaining chunk
		1287	$_[0]->unshift_read (chunk => $len, sub {
		1288	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1289	$cb->($_[0], $ref);
		1290	} else {
		1291	$self->_error (&Errno::EBADMSG);
		1292	}
		1293	});
		1294	}
		1295
		1296	1
891	}	1297	}
892	};	1298	};
893		1299
894	=back	1300	=back
895		1301
…		…
916	=item $handle->stop_read	1322	=item $handle->stop_read
917		1323
918	=item $handle->start_read	1324	=item $handle->start_read
919		1325
920	In rare cases you actually do not want to read anything from the	1326	In rare cases you actually do not want to read anything from the
921	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1327	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
922	any queued callbacks will be executed then. To start reading again, call	1328	any queued callbacks will be executed then. To start reading again, call
923	C<start_read>.	1329	C<start_read>.
924		1330
		1331	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1332	you change the C<on_read> callback or push/unshift a read callback, and it
		1333	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1334	there are any read requests in the queue.
		1335
		1336	These methods will have no effect when in TLS mode (as TLS doesn't support
		1337	half-duplex connections).
		1338
925	=cut	1339	=cut
926		1340
927	sub stop_read {	1341	sub stop_read {
928	my ($self) = @_;	1342	my ($self) = @_;
929		1343
930	delete $self->{_rw};	1344	delete $self->{_rw} unless $self->{tls};
931	}	1345	}
932		1346
933	sub start_read {	1347	sub start_read {
934	my ($self) = @_;	1348	my ($self) = @_;
935		1349
936	unless ($self->{_rw} || $self->{_eof}) {	1350	unless ($self->{_rw} || $self->{_eof}) {
937	Scalar::Util::weaken $self;	1351	Scalar::Util::weaken $self;
938		1352
939	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1353	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
940	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1354	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
941	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1355	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
942		1356
943	if ($len > 0) {	1357	if ($len > 0) {
944	$self->{filter_r}	1358	$self->{_activity} = AnyEvent->now;
945	? $self->{filter_r}->($self, $rbuf)	1359
946	: $self->_drain_rbuf;	1360	if ($self->{tls}) {
		1361	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1362
		1363	&_dotls ($self);
		1364	} else {
		1365	$self->_drain_rbuf unless $self->{_in_drain};
		1366	}
947		1367
948	} elsif (defined $len) {	1368	} elsif (defined $len) {
949	delete $self->{_rw};	1369	delete $self->{_rw};
950	$self->{_eof} = 1;	1370	$self->{_eof} = 1;
951	$self->_drain_rbuf;	1371	$self->_drain_rbuf unless $self->{_in_drain};
952		1372
953	} elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) {	1373	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
954	return $self->error;	1374	return $self->_error ($!, 1);
955	}	1375	}
956	});	1376	});
957	}	1377	}
958	}	1378	}
959		1379
		1380	our $ERROR_SYSCALL;
		1381	our $ERROR_WANT_READ;
		1382	our $ERROR_ZERO_RETURN;
		1383
		1384	sub _tls_error {
		1385	my ($self, $err) = @_;
		1386
		1387	return $self->_error ($!, 1)
		1388	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1389
		1390	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1391
		1392	# reduce error string to look less scary
		1393	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1394
		1395	$self->_error (&Errno::EPROTO, 1, $err);
		1396	}
		1397
		1398	# poll the write BIO and send the data if applicable
		1399	# also decode read data if possible
		1400	# this is basiclaly our TLS state machine
		1401	# more efficient implementations are possible with openssl,
		1402	# but not with the buggy and incomplete Net::SSLeay.
960	sub _dotls {	1403	sub _dotls {
961	my ($self) = @_;	1404	my ($self) = @_;
962		1405
		1406	my $tmp;
		1407
963	if (length $self->{_tls_wbuf}) {	1408	if (length $self->{_tls_wbuf}) {
964	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1409	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
965	substr $self->{_tls_wbuf}, 0, $len, "";	1410	substr $self->{_tls_wbuf}, 0, $tmp, "";
966	}	1411	}
967	}
968		1412
		1413	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1414	return $self->_tls_error ($tmp)
		1415	if $tmp != $ERROR_WANT_READ
		1416	&& ($tmp != $ERROR_SYSCALL || $!)
		1417	&& $tmp != $ERROR_ZERO_RETURN;
		1418	}
		1419
		1420	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1421	unless (length $tmp) {
		1422	# let's treat SSL-eof as we treat normal EOF
		1423	delete $self->{_rw};
		1424	$self->{_eof} = 1;
		1425	&_freetls;
		1426	}
		1427
		1428	$self->{_tls_rbuf} .= $tmp;
		1429	$self->_drain_rbuf unless $self->{_in_drain};
		1430	$self->{tls} or return; # tls session might have gone away in callback
		1431	}
		1432
		1433	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1434	return $self->_tls_error ($tmp)
		1435	if $tmp != $ERROR_WANT_READ
		1436	&& ($tmp != $ERROR_SYSCALL || $!)
		1437	&& $tmp != $ERROR_ZERO_RETURN;
		1438
969	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1439	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
970	$self->{wbuf} .= $buf;	1440	$self->{wbuf} .= $tmp;
971	$self->_drain_wbuf;	1441	$self->_drain_wbuf;
972	}
973
974	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
975	$self->{rbuf} .= $buf;
976	$self->_drain_rbuf;
977	}
978
979	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
980
981	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
982	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
983	$self->error;
984	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
985	$! = &Errno::EIO;
986	$self->error;
987	}
988
989	# all others are fine for our purposes
990	}	1442	}
991	}	1443	}
992		1444
993	=item $handle->starttls ($tls[, $tls_ctx])	1445	=item $handle->starttls ($tls[, $tls_ctx])
994		1446
…		…
997	C<starttls>.	1449	C<starttls>.
998		1450
999	The first argument is the same as the C<tls> constructor argument (either	1451	The first argument is the same as the C<tls> constructor argument (either
1000	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1452	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1001		1453
1002	The second argument is the optional C<Net::SSLeay::CTX> object that is	1454	The second argument is the optional C<AnyEvent::TLS> object that is used
1003	used when AnyEvent::Handle has to create its own TLS connection object.	1455	when AnyEvent::Handle has to create its own TLS connection object, or
		1456	a hash reference with C<< key => value >> pairs that will be used to
		1457	construct a new context.
1004		1458
1005	The TLS connection object will end up in C<< $handle->{tls} >> after this	1459	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1006	call and can be used or changed to your liking. Note that the handshake	1460	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1007	might have already started when this function returns.	1461	changed to your liking. Note that the handshake might have already started
		1462	when this function returns.
1008		1463
1009	=cut	1464	If it an error to start a TLS handshake more than once per
		1465	AnyEvent::Handle object (this is due to bugs in OpenSSL).
1010		1466
1011	# TODO: maybe document...	1467	=cut
		1468
		1469	our %TLS_CACHE; #TODO not yet documented, should we?
		1470
1012	sub starttls {	1471	sub starttls {
1013	my ($self, $ssl, $ctx) = @_;	1472	my ($self, $ssl, $ctx) = @_;
1014		1473
1015	$self->stoptls;	1474	require Net::SSLeay;
1016		1475
1017	if ($ssl eq "accept") {	1476	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1018	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1477	if $self->{tls};
1019	Net::SSLeay::set_accept_state ($ssl);	1478
1020	} elsif ($ssl eq "connect") {	1479	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1021	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1480	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1022	Net::SSLeay::set_connect_state ($ssl);	1481	$ERROR_ZERO_RETURN = Net::SSLeay::ERROR_ZERO_RETURN ();
		1482
		1483	$ctx ||= $self->{tls_ctx};
		1484
		1485	if ("HASH" eq ref $ctx) {
		1486	require AnyEvent::TLS;
		1487
		1488	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
		1489
		1490	if ($ctx->{cache}) {
		1491	my $key = $ctx+0;
		1492	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1493	} else {
		1494	$ctx = new AnyEvent::TLS %$ctx;
		1495	}
		1496	}
1023	}	1497
1024		1498	$self->{tls_ctx} = $ctx || TLS_CTX ();
1025	$self->{tls} = $ssl;	1499	$self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});
1026		1500
1027	# basically, this is deep magic (because SSL_read should have the same issues)	1501	# basically, this is deep magic (because SSL_read should have the same issues)
1028	# but the openssl maintainers basically said: "trust us, it just works".	1502	# but the openssl maintainers basically said: "trust us, it just works".
1029	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1503	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1030	# and mismaintained ssleay-module doesn't even offer them).	1504	# and mismaintained ssleay-module doesn't even offer them).
1031	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1505	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1506	#
		1507	# in short: this is a mess.
		1508	#
		1509	# note that we do not try to keep the length constant between writes as we are required to do.
		1510	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1511	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1512	# have identity issues in that area.
1032	Net::SSLeay::CTX_set_mode ($self->{tls},	1513	# Net::SSLeay::CTX_set_mode ($ssl,
1033	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1514	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1034	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1515	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1516	Net::SSLeay::CTX_set_mode ($ssl, 1|2);
1035		1517
1036	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1518	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1037	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1519	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1038		1520
1039	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1521	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1040		1522
1041	$self->{filter_w} = sub {	1523	&_dotls; # need to trigger the initial handshake
1042	$_[0]{_tls_wbuf} .= ${$_[1]};	1524	$self->start_read; # make sure we actually do read
1043	&_dotls;
1044	};
1045	$self->{filter_r} = sub {
1046	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1047	&_dotls;
1048	};
1049	}	1525	}
1050		1526
1051	=item $handle->stoptls	1527	=item $handle->stoptls
1052		1528
1053	Destroys the SSL connection, if any. Partial read or write data will be	1529	Shuts down the SSL connection - this makes a proper EOF handshake by
1054	lost.	1530	sending a close notify to the other side, but since OpenSSL doesn't
		1531	support non-blocking shut downs, it is not possible to re-use the stream
		1532	afterwards.
1055		1533
1056	=cut	1534	=cut
1057		1535
1058	sub stoptls {	1536	sub stoptls {
1059	my ($self) = @_;	1537	my ($self) = @_;
1060		1538
1061	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1539	if ($self->{tls}) {
		1540	Net::SSLeay::shutdown ($self->{tls});
1062		1541
1063	delete $self->{_rbio};	1542	&_dotls;
1064	delete $self->{_wbio};	1543
1065	delete $self->{_tls_wbuf};	1544	# we don't give a shit. no, we do, but we can't. no...
1066	delete $self->{filter_r};	1545	# we, we... have to use openssl :/
1067	delete $self->{filter_w};	1546	&_freetls;
		1547	}
		1548	}
		1549
		1550	sub _freetls {
		1551	my ($self) = @_;
		1552
		1553	return unless $self->{tls};
		1554
		1555	$self->{tls_ctx}->_put_session (delete $self->{tls});
		1556
		1557	delete @$self{qw(_rbio _wbio _tls_wbuf)};
1068	}	1558	}
1069		1559
1070	sub DESTROY {	1560	sub DESTROY {
1071	my $self = shift;	1561	my ($self) = @_;
1072		1562
1073	$self->stoptls;	1563	&_freetls;
		1564
		1565	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1566
		1567	if ($linger && length $self->{wbuf}) {
		1568	my $fh = delete $self->{fh};
		1569	my $wbuf = delete $self->{wbuf};
		1570
		1571	my @linger;
		1572
		1573	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1574	my $len = syswrite $fh, $wbuf, length $wbuf;
		1575
		1576	if ($len > 0) {
		1577	substr $wbuf, 0, $len, "";
		1578	} else {
		1579	@linger = (); # end
		1580	}
		1581	});
		1582	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1583	@linger = ();
		1584	});
		1585	}
		1586	}
		1587
		1588	=item $handle->destroy
		1589
		1590	Shuts down the handle object as much as possible - this call ensures that
		1591	no further callbacks will be invoked and resources will be freed as much
		1592	as possible. You must not call any methods on the object afterwards.
		1593
		1594	Normally, you can just "forget" any references to an AnyEvent::Handle
		1595	object and it will simply shut down. This works in fatal error and EOF
		1596	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1597	callback, so when you want to destroy the AnyEvent::Handle object from
		1598	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1599	that case.
		1600
		1601	The handle might still linger in the background and write out remaining
		1602	data, as specified by the C<linger> option, however.
		1603
		1604	=cut
		1605
		1606	sub destroy {
		1607	my ($self) = @_;
		1608
		1609	$self->DESTROY;
		1610	%$self = ();
1074	}	1611	}
1075		1612
1076	=item AnyEvent::Handle::TLS_CTX	1613	=item AnyEvent::Handle::TLS_CTX
1077		1614
1078	This function creates and returns the Net::SSLeay::CTX object used by	1615	This function creates and returns the AnyEvent::TLS object used by default
1079	default for TLS mode.	1616	for TLS mode.
1080		1617
1081	The context is created like this:	1618	The context is created by calling L<AnyEvent::TLS> without any arguments.
1082
1083	Net::SSLeay::load_error_strings;
1084	Net::SSLeay::SSLeay_add_ssl_algorithms;
1085	Net::SSLeay::randomize;
1086
1087	my $CTX = Net::SSLeay::CTX_new;
1088
1089	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1090		1619
1091	=cut	1620	=cut
1092		1621
1093	our $TLS_CTX;	1622	our $TLS_CTX;
1094		1623
1095	sub TLS_CTX() {	1624	sub TLS_CTX() {
1096	$TLS_CTX || do {	1625	$TLS_CTX ||= do {
1097	require Net::SSLeay;	1626	require AnyEvent::TLS;
1098		1627
1099	Net::SSLeay::load_error_strings ();	1628	new AnyEvent::TLS
1100	Net::SSLeay::SSLeay_add_ssl_algorithms ();
1101	Net::SSLeay::randomize ();
1102
1103	$TLS_CTX = Net::SSLeay::CTX_new ();
1104
1105	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1106
1107	$TLS_CTX
1108	}	1629	}
1109	}	1630	}
1110		1631
1111	=back	1632	=back
		1633
		1634
		1635	=head1 NONFREQUENTLY ASKED QUESTIONS
		1636
		1637	=over 4
		1638
		1639	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1640	still get further invocations!
		1641
		1642	That's because AnyEvent::Handle keeps a reference to itself when handling
		1643	read or write callbacks.
		1644
		1645	It is only safe to "forget" the reference inside EOF or error callbacks,
		1646	from within all other callbacks, you need to explicitly call the C<<
		1647	->destroy >> method.
		1648
		1649	=item I get different callback invocations in TLS mode/Why can't I pause
		1650	reading?
		1651
		1652	Unlike, say, TCP, TLS connections do not consist of two independent
		1653	communication channels, one for each direction. Or put differently. The
		1654	read and write directions are not independent of each other: you cannot
		1655	write data unless you are also prepared to read, and vice versa.
		1656
		1657	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1658	callback invocations when you are not expecting any read data - the reason
		1659	is that AnyEvent::Handle always reads in TLS mode.
		1660
		1661	During the connection, you have to make sure that you always have a
		1662	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1663	connection (or when you no longer want to use it) you can call the
		1664	C<destroy> method.
		1665
		1666	=item How do I read data until the other side closes the connection?
		1667
		1668	If you just want to read your data into a perl scalar, the easiest way
		1669	to achieve this is by setting an C<on_read> callback that does nothing,
		1670	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1671	will be in C<$_[0]{rbuf}>:
		1672
		1673	$handle->on_read (sub { });
		1674	$handle->on_eof (undef);
		1675	$handle->on_error (sub {
		1676	my $data = delete $_[0]{rbuf};
		1677	undef $handle;
		1678	});
		1679
		1680	The reason to use C<on_error> is that TCP connections, due to latencies
		1681	and packets loss, might get closed quite violently with an error, when in
		1682	fact, all data has been received.
		1683
		1684	It is usually better to use acknowledgements when transferring data,
		1685	to make sure the other side hasn't just died and you got the data
		1686	intact. This is also one reason why so many internet protocols have an
		1687	explicit QUIT command.
		1688
		1689	=item I don't want to destroy the handle too early - how do I wait until
		1690	all data has been written?
		1691
		1692	After writing your last bits of data, set the C<on_drain> callback
		1693	and destroy the handle in there - with the default setting of
		1694	C<low_water_mark> this will be called precisely when all data has been
		1695	written to the socket:
		1696
		1697	$handle->push_write (...);
		1698	$handle->on_drain (sub {
		1699	warn "all data submitted to the kernel\n";
		1700	undef $handle;
		1701	});
		1702
		1703	=back
		1704
1112		1705
1113	=head1 SUBCLASSING AnyEvent::Handle	1706	=head1 SUBCLASSING AnyEvent::Handle
1114		1707
1115	In many cases, you might want to subclass AnyEvent::Handle.	1708	In many cases, you might want to subclass AnyEvent::Handle.
1116		1709
…		…
1120	=over 4	1713	=over 4
1121		1714
1122	=item * all constructor arguments become object members.	1715	=item * all constructor arguments become object members.
1123		1716
1124	At least initially, when you pass a C<tls>-argument to the constructor it	1717	At least initially, when you pass a C<tls>-argument to the constructor it
1125	will end up in C<< $handle->{tls} >>. Those members might be changes or	1718	will end up in C<< $handle->{tls} >>. Those members might be changed or
1126	mutated later on (for example C<tls> will hold the TLS connection object).	1719	mutated later on (for example C<tls> will hold the TLS connection object).
1127		1720
1128	=item * other object member names are prefixed with an C<_>.	1721	=item * other object member names are prefixed with an C<_>.
1129		1722
1130	All object members not explicitly documented (internal use) are prefixed	1723	All object members not explicitly documented (internal use) are prefixed

Diff Legend

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