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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.53 by root, Mon Jun 2 09:12:14 2008 UTC vs.
Revision 1.143 by root, Mon Jul 6 21:02:34 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(WSAEWOULDBLOCK);	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
…		…
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 = 4.1;	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 when an end-of-file condition is detcted,	84	Set the callback to be called when an end-of-file condition is detected,
81	i.e. in the case of a socket, when the other side has closed the	85	i.e. in the case of a socket, when the other side has closed the
82	connection cleanly.	86	connection cleanly.
83		87
		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
84	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,
85	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
86	waiting for data.	95	waiting for data.
87		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
88	=item on_error => $cb->($handle, $fatal)	100	=item on_error => $cb->($handle, $fatal, $message)
89		101
90	This is the error callback, which is called when, well, some error	102	This is the error callback, which is called when, well, some error
91	occured, such as not being able to resolve the hostname, failure to	103	occured, such as not being able to resolve the hostname, failure to
92	connect or a read error.	104	connect or a read error.
93		105
94	Some errors are fatal (which is indicated by C<$fatal> being true). On	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
95	fatal errors the handle object will be shut down and will not be	107	fatal errors the handle object will be shut down and will not be usable
		108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		109	errors are an EOF condition with active (but unsatisifable) read watchers
		110	(C<EPIPE>) or I/O errors.
		111
		112	AnyEvent::Handle tries to find an appropriate error code for you to check
		113	against, but in some cases (TLS errors), this does not work well. It is
		114	recommended to always output the C<$message> argument in human-readable
		115	error messages (it's usually the same as C<"$!">).
		116
96	usable. Non-fatal errors can be retried by simply returning, but it is	117	Non-fatal errors can be retried by simply returning, but it is recommended
97	recommended to simply ignore this parameter and instead abondon the handle	118	to simply ignore this parameter and instead abondon the handle object
98	object when this callback is invoked.	119	when this callback is invoked. Examples of non-fatal errors are timeouts
		120	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99		121
100	On callback entrance, the value of C<$!> contains the operating system	122	On callback entrance, the value of C<$!> contains the operating system
101	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).	123	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		124	C<EPROTO>).
102		125
103	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
104	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
105	C<croak>.	128	C<croak>.
106		129
107	=item on_read => $cb->($handle)	130	=item on_read => $cb->($handle)
108		131
109	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
110	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).
111		136
112	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 >>
113	method or access the C<$handle->{rbuf}> member directly.	138	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		139	must not enlarge or modify the read buffer, you can only remove data at
		140	the beginning from it.
114		141
115	When an EOF condition is detected then AnyEvent::Handle will first try to	142	When an EOF condition is detected then AnyEvent::Handle will first try to
116	feed all the remaining data to the queued callbacks and C<on_read> before	143	feed all the remaining data to the queued callbacks and C<on_read> before
117	calling the C<on_eof> callback. If no progress can be made, then a fatal	144	calling the C<on_eof> callback. If no progress can be made, then a fatal
118	error will be raised (with C<$!> set to C<EPIPE>).	145	error will be raised (with C<$!> set to C<EPIPE>).
…		…
122	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
123	(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).
124		151
125	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.
126		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
127	=item timeout => $fractional_seconds	160	=item timeout => $fractional_seconds
128		161
129	If non-zero, then this enables an "inactivity" timeout: whenever this many	162	If non-zero, then this enables an "inactivity" timeout: whenever this many
130	seconds pass without a successful read or write on the underlying file	163	seconds pass without a successful read or write on the underlying file
131	handle, the C<on_timeout> callback will be invoked (and if that one is	164	handle, the C<on_timeout> callback will be invoked (and if that one is
132	missing, an C<ETIMEDOUT> error will be raised).	165	missing, a non-fatal C<ETIMEDOUT> error will be raised).
133		166
134	Note that timeout processing is also active when you currently do not have	167	Note that timeout processing is also active when you currently do not have
135	any outstanding read or write requests: If you plan to keep the connection	168	any outstanding read or write requests: If you plan to keep the connection
136	idle then you should disable the timout temporarily or ignore the timeout	169	idle then you should disable the timout temporarily or ignore the timeout
137	in the C<on_timeout> callback.	170	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		171	restart the timeout.
138		172
139	Zero (the default) disables this timeout.	173	Zero (the default) disables this timeout.
140		174
141	=item on_timeout => $cb->($handle)	175	=item on_timeout => $cb->($handle)
142		176
…		…
146		180
147	=item rbuf_max => <bytes>	181	=item rbuf_max => <bytes>
148		182
149	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>)
150	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
151	avoid denial-of-service attacks.	185	avoid some forms of denial-of-service attacks.
152		186
153	For example, a server accepting connections from untrusted sources should	187	For example, a server accepting connections from untrusted sources should
154	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
155	(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
156	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
157	isn't finished).	191	isn't finished).
158		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
159	=item read_size => <bytes>	219	=item read_size => <bytes>
160		220
161	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
162	during each (loop iteration). Default: C<8192>.	222	try to read during each loop iteration, which affects memory
		223	requirements). Default: C<8192>.
163		224
164	=item low_water_mark => <bytes>	225	=item low_water_mark => <bytes>
165		226
166	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
167	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
168	considered empty.	229	considered empty.
169		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	peername verification (see C<verify_peername> in L<AnyEvent::TLS>).
		255
170	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	256	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
171		257
172	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
173	will start making tls handshake and will transparently encrypt/decrypt	259	AnyEvent will start a TLS handshake as soon as the conenction has been
174	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.
175		264
176	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
177	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.
178		269
179	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
180	connection, use C<connect> mode.	271	C<accept>, and for the TLS client side of a connection, use C<connect>
		272	mode.
181		273
182	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
183	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>
184	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
185	AnyEvent::Handle.	277	AnyEvent::Handle. Also, this module will take ownership of this connection
		278	object.
186		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
187	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.
188		290
189	=item tls_ctx => $ssl_ctx	291	=item tls_ctx => $anyevent_tls
190		292
191	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
192	(unless a connection object was specified directly). If this parameter is	294	(unless a connection object was specified directly). If this parameter is
193	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	295	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
194		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
		301	=item on_starttls => $cb->($handle, $success[, $error_message])
		302
		303	This callback will be invoked when the TLS/SSL handshake has finished. If
		304	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		305	(C<on_stoptls> will not be called in this case).
		306
		307	The session in C<< $handle->{tls} >> can still be examined in this
		308	callback, even when the handshake was not successful.
		309
		310	TLS handshake failures will not cause C<on_error> to be invoked when this
		311	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		312
		313	Without this callback, handshake failures lead to C<on_error> being
		314	called, as normal.
		315
		316	Note that you cannot call C<starttls> right again in this callback. If you
		317	need to do that, start an zero-second timer instead whose callback can
		318	then call C<< ->starttls >> again.
		319
		320	=item on_stoptls => $cb->($handle)
		321
		322	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		323	set, then it will be invoked after freeing the TLS session. If it is not,
		324	then a TLS shutdown condition will be treated like a normal EOF condition
		325	on the handle.
		326
		327	The session in C<< $handle->{tls} >> can still be examined in this
		328	callback.
		329
		330	This callback will only be called on TLS shutdowns, not when the
		331	underlying handle signals EOF.
		332
195	=item json => JSON or JSON::XS object	333	=item json => JSON or JSON::XS object
196		334
197	This is the json coder object used by the C<json> read and write types.	335	This is the json coder object used by the C<json> read and write types.
198		336
199	If you don't supply it, then AnyEvent::Handle will create and use a	337	If you don't supply it, then AnyEvent::Handle will create and use a
200	suitable one, which will write and expect UTF-8 encoded JSON texts.	338	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		339	texts.
201		340
202	Note that you are responsible to depend on the JSON module if you want to	341	Note that you are responsible to depend on the JSON module if you want to
203	use this functionality, as AnyEvent does not have a dependency itself.	342	use this functionality, as AnyEvent does not have a dependency itself.
204		343
205	=item filter_r => $cb
206
207	=item filter_w => $cb
208
209	These exist, but are undocumented at this time.
210
211	=back	344	=back
212		345
213	=cut	346	=cut
214		347
215	sub new {	348	sub new {
216	my $class = shift;	349	my $class = shift;
217
218	my $self = bless { @_ }, $class;	350	my $self = bless { @_ }, $class;
219		351
220	$self->{fh} or Carp::croak "mandatory argument fh is missing";	352	$self->{fh} or Carp::croak "mandatory argument fh is missing";
221		353
222	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	354	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
223
224	if ($self->{tls}) {
225	require Net::SSLeay;
226	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
227	}
228
229	# $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; # nop
230	# $self->on_error (delete $self->{on_error}) if $self->{on_error}; # nop
231	# $self->on_read (delete $self->{on_read} ) if $self->{on_read}; # nop
232	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
233		355
234	$self->{_activity} = AnyEvent->now;	356	$self->{_activity} = AnyEvent->now;
235	$self->_timeout;	357	$self->_timeout;
236		358
		359	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
		360
		361	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
		362	if $self->{tls};
		363
		364	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
		365
237	$self->start_read;	366	$self->start_read
		367	if $self->{on_read};
238		368
239	$self	369	$self->{fh} && $self
240	}	370	}
241		371
242	sub _shutdown {	372	sub _shutdown {
243	my ($self) = @_;	373	my ($self) = @_;
244		374
245	delete $self->{_tw};	375	delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
246	delete $self->{_rw};	376	$self->{_eof} = 1; # tell starttls et. al to stop trying
247	delete $self->{_ww};
248	delete $self->{fh};
249		377
250	$self->stoptls;	378	&_freetls;
251	}	379	}
252		380
253	sub _error {	381	sub _error {
254	my ($self, $errno, $fatal) = @_;	382	my ($self, $errno, $fatal, $message) = @_;
255		383
256	$self->_shutdown	384	$self->_shutdown
257	if $fatal;	385	if $fatal;
258		386
259	$! = $errno;	387	$! = $errno;
		388	$message ||= "$!";
260		389
261	if ($self->{on_error}) {	390	if ($self->{on_error}) {
262	$self->{on_error}($self, $fatal);	391	$self->{on_error}($self, $fatal, $message);
263	} else {	392	} elsif ($self->{fh}) {
264	Carp::croak "AnyEvent::Handle uncaught error: $!";	393	Carp::croak "AnyEvent::Handle uncaught error: $message";
265	}	394	}
266	}	395	}
267		396
268	=item $fh = $handle->fh	397	=item $fh = $handle->fh
269		398
270	This method returns the file handle of the L<AnyEvent::Handle> object.	399	This method returns the file handle used to create the L<AnyEvent::Handle> object.
271		400
272	=cut	401	=cut
273		402
274	sub fh { $_[0]{fh} }	403	sub fh { $_[0]{fh} }
275		404
…		…
293	$_[0]{on_eof} = $_[1];	422	$_[0]{on_eof} = $_[1];
294	}	423	}
295		424
296	=item $handle->on_timeout ($cb)	425	=item $handle->on_timeout ($cb)
297		426
298	Replace the current C<on_timeout> callback, or disables the callback	427	Replace the current C<on_timeout> callback, or disables the callback (but
299	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor	428	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
300	argument.	429	argument and method.
301		430
302	=cut	431	=cut
303		432
304	sub on_timeout {	433	sub on_timeout {
305	$_[0]{on_timeout} = $_[1];	434	$_[0]{on_timeout} = $_[1];
		435	}
		436
		437	=item $handle->autocork ($boolean)
		438
		439	Enables or disables the current autocork behaviour (see C<autocork>
		440	constructor argument). Changes will only take effect on the next write.
		441
		442	=cut
		443
		444	sub autocork {
		445	$_[0]{autocork} = $_[1];
		446	}
		447
		448	=item $handle->no_delay ($boolean)
		449
		450	Enables or disables the C<no_delay> setting (see constructor argument of
		451	the same name for details).
		452
		453	=cut
		454
		455	sub no_delay {
		456	$_[0]{no_delay} = $_[1];
		457
		458	eval {
		459	local $SIG{__DIE__};
		460	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		461	};
		462	}
		463
		464	=item $handle->on_starttls ($cb)
		465
		466	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		467
		468	=cut
		469
		470	sub on_starttls {
		471	$_[0]{on_starttls} = $_[1];
		472	}
		473
		474	=item $handle->on_stoptls ($cb)
		475
		476	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		477
		478	=cut
		479
		480	sub on_starttls {
		481	$_[0]{on_stoptls} = $_[1];
306	}	482	}
307		483
308	#############################################################################	484	#############################################################################
309		485
310	=item $handle->timeout ($seconds)	486	=item $handle->timeout ($seconds)
…		…
339	$self->{on_timeout}($self);	515	$self->{on_timeout}($self);
340	} else {	516	} else {
341	$self->_error (&Errno::ETIMEDOUT);	517	$self->_error (&Errno::ETIMEDOUT);
342	}	518	}
343		519
344	# callbakx could have changed timeout value, optimise	520	# callback could have changed timeout value, optimise
345	return unless $self->{timeout};	521	return unless $self->{timeout};
346		522
347	# calculate new after	523	# calculate new after
348	$after = $self->{timeout};	524	$after = $self->{timeout};
349	}	525	}
350		526
351	Scalar::Util::weaken $self;	527	Scalar::Util::weaken $self;
		528	return unless $self; # ->error could have destroyed $self
352		529
353	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {	530	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
354	delete $self->{_tw};	531	delete $self->{_tw};
355	$self->_timeout;	532	$self->_timeout;
356	});	533	});
…		…
387	my ($self, $cb) = @_;	564	my ($self, $cb) = @_;
388		565
389	$self->{on_drain} = $cb;	566	$self->{on_drain} = $cb;
390		567
391	$cb->($self)	568	$cb->($self)
392	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	569	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
393	}	570	}
394		571
395	=item $handle->push_write ($data)	572	=item $handle->push_write ($data)
396		573
397	Queues the given scalar to be written. You can push as much data as you	574	Queues the given scalar to be written. You can push as much data as you
…		…
414	substr $self->{wbuf}, 0, $len, "";	591	substr $self->{wbuf}, 0, $len, "";
415		592
416	$self->{_activity} = AnyEvent->now;	593	$self->{_activity} = AnyEvent->now;
417		594
418	$self->{on_drain}($self)	595	$self->{on_drain}($self)
419	if $self->{low_water_mark} >= length $self->{wbuf}	596	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
420	&& $self->{on_drain};	597	&& $self->{on_drain};
421		598
422	delete $self->{_ww} unless length $self->{wbuf};	599	delete $self->{_ww} unless length $self->{wbuf};
423	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	600	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
424	$self->_error ($!, 1);	601	$self->_error ($!, 1);
425	}	602	}
426	};	603	};
427		604
428	# try to write data immediately	605	# try to write data immediately
429	$cb->();	606	$cb->() unless $self->{autocork};
430		607
431	# if still data left in wbuf, we need to poll	608	# if still data left in wbuf, we need to poll
432	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	609	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
433	if length $self->{wbuf};	610	if length $self->{wbuf};
434	};	611	};
…		…
448		625
449	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	626	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
450	->($self, @_);	627	->($self, @_);
451	}	628	}
452		629
453	if ($self->{filter_w}) {	630	if ($self->{tls}) {
454	$self->{filter_w}($self, \$_[0]);	631	$self->{_tls_wbuf} .= $_[0];
		632
		633	&_dotls ($self);
455	} else {	634	} else {
456	$self->{wbuf} .= $_[0];	635	$self->{wbuf} .= $_[0];
457	$self->_drain_wbuf;	636	$self->_drain_wbuf;
458	}	637	}
459	}	638	}
…		…
476	=cut	655	=cut
477		656
478	register_write_type netstring => sub {	657	register_write_type netstring => sub {
479	my ($self, $string) = @_;	658	my ($self, $string) = @_;
480		659
481	sprintf "%d:%s,", (length $string), $string	660	(length $string) . ":$string,"
		661	};
		662
		663	=item packstring => $format, $data
		664
		665	An octet string prefixed with an encoded length. The encoding C<$format>
		666	uses the same format as a Perl C<pack> format, but must specify a single
		667	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		668	optional C<!>, C<< < >> or C<< > >> modifier).
		669
		670	=cut
		671
		672	register_write_type packstring => sub {
		673	my ($self, $format, $string) = @_;
		674
		675	pack "$format/a*", $string
482	};	676	};
483		677
484	=item json => $array_or_hashref	678	=item json => $array_or_hashref
485		679
486	Encodes the given hash or array reference into a JSON object. Unless you	680	Encodes the given hash or array reference into a JSON object. Unless you
…		…
520		714
521	$self->{json} ? $self->{json}->encode ($ref)	715	$self->{json} ? $self->{json}->encode ($ref)
522	: JSON::encode_json ($ref)	716	: JSON::encode_json ($ref)
523	};	717	};
524		718
		719	=item storable => $reference
		720
		721	Freezes the given reference using L<Storable> and writes it to the
		722	handle. Uses the C<nfreeze> format.
		723
		724	=cut
		725
		726	register_write_type storable => sub {
		727	my ($self, $ref) = @_;
		728
		729	require Storable;
		730
		731	pack "w/a*", Storable::nfreeze ($ref)
		732	};
		733
525	=back	734	=back
		735
		736	=item $handle->push_shutdown
		737
		738	Sometimes you know you want to close the socket after writing your data
		739	before it was actually written. One way to do that is to replace your
		740	C<on_drain> handler by a callback that shuts down the socket (and set
		741	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		742	replaces the C<on_drain> callback with:
		743
		744	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		745
		746	This simply shuts down the write side and signals an EOF condition to the
		747	the peer.
		748
		749	You can rely on the normal read queue and C<on_eof> handling
		750	afterwards. This is the cleanest way to close a connection.
		751
		752	=cut
		753
		754	sub push_shutdown {
		755	my ($self) = @_;
		756
		757	delete $self->{low_water_mark};
		758	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		759	}
526		760
527	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	761	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
528		762
529	This function (not method) lets you add your own types to C<push_write>.	763	This function (not method) lets you add your own types to C<push_write>.
530	Whenever the given C<type> is used, C<push_write> will invoke the code	764	Whenever the given C<type> is used, C<push_write> will invoke the code
…		…
551	ways, the "simple" way, using only C<on_read> and the "complex" way, using	785	ways, the "simple" way, using only C<on_read> and the "complex" way, using
552	a queue.	786	a queue.
553		787
554	In the simple case, you just install an C<on_read> callback and whenever	788	In the simple case, you just install an C<on_read> callback and whenever
555	new data arrives, it will be called. You can then remove some data (if	789	new data arrives, it will be called. You can then remove some data (if
556	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	790	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
557	or not.	791	leave the data there if you want to accumulate more (e.g. when only a
		792	partial message has been received so far).
558		793
559	In the more complex case, you want to queue multiple callbacks. In this	794	In the more complex case, you want to queue multiple callbacks. In this
560	case, AnyEvent::Handle will call the first queued callback each time new	795	case, AnyEvent::Handle will call the first queued callback each time new
561	data arrives and removes it when it has done its job (see C<push_read>,	796	data arrives (also the first time it is queued) and removes it when it has
562	below).	797	done its job (see C<push_read>, below).
563		798
564	This way you can, for example, push three line-reads, followed by reading	799	This way you can, for example, push three line-reads, followed by reading
565	a chunk of data, and AnyEvent::Handle will execute them in order.	800	a chunk of data, and AnyEvent::Handle will execute them in order.
566		801
567	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	802	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
…		…
580	# handle xml	815	# handle xml
581	});	816	});
582	});	817	});
583	});	818	});
584		819
585	Example 2: Implement a client for a protocol that replies either with	820	Example 2: Implement a client for a protocol that replies either with "OK"
586	"OK" and another line or "ERROR" for one request, and 64 bytes for the	821	and another line or "ERROR" for the first request that is sent, and 64
587	second request. Due tot he availability of a full queue, we can just	822	bytes for the second request. Due to the availability of a queue, we can
588	pipeline sending both requests and manipulate the queue as necessary in	823	just pipeline sending both requests and manipulate the queue as necessary
589	the callbacks:	824	in the callbacks.
590		825
591	# request one	826	When the first callback is called and sees an "OK" response, it will
		827	C<unshift> another line-read. This line-read will be queued I<before> the
		828	64-byte chunk callback.
		829
		830	# request one, returns either "OK + extra line" or "ERROR"
592	$handle->push_write ("request 1\015\012");	831	$handle->push_write ("request 1\015\012");
593		832
594	# we expect "ERROR" or "OK" as response, so push a line read	833	# we expect "ERROR" or "OK" as response, so push a line read
595	$handle->push_read (line => sub {	834	$handle->push_read (line => sub {
596	# if we got an "OK", we have to _prepend_ another line,	835	# if we got an "OK", we have to _prepend_ another line,
…		…
603	...	842	...
604	});	843	});
605	}	844	}
606	});	845	});
607		846
608	# request two	847	# request two, simply returns 64 octets
609	$handle->push_write ("request 2\015\012");	848	$handle->push_write ("request 2\015\012");
610		849
611	# simply read 64 bytes, always	850	# simply read 64 bytes, always
612	$handle->push_read (chunk => 64, sub {	851	$handle->push_read (chunk => 64, sub {
613	my $response = $_[1];	852	my $response = $_[1];
…		…
619	=cut	858	=cut
620		859
621	sub _drain_rbuf {	860	sub _drain_rbuf {
622	my ($self) = @_;	861	my ($self) = @_;
623		862
		863	local $self->{_in_drain} = 1;
		864
624	if (	865	if (
625	defined $self->{rbuf_max}	866	defined $self->{rbuf_max}
626	&& $self->{rbuf_max} < length $self->{rbuf}	867	&& $self->{rbuf_max} < length $self->{rbuf}
627	) {	868	) {
628	return $self->_error (&Errno::ENOSPC, 1);	869	$self->_error (&Errno::ENOSPC, 1), return;
629	}	870	}
630		871
631	return if $self->{in_drain};	872	while () {
632	local $self->{in_drain} = 1;	873	# we need to use a separate tls read buffer, as we must not receive data while
		874	# we are draining the buffer, and this can only happen with TLS.
		875	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
633		876
634	while (my $len = length $self->{rbuf}) {	877	my $len = length $self->{rbuf};
635	no strict 'refs';	878
636	if (my $cb = shift @{ $self->{_queue} }) {	879	if (my $cb = shift @{ $self->{_queue} }) {
637	unless ($cb->($self)) {	880	unless ($cb->($self)) {
638	if ($self->{_eof}) {	881	if ($self->{_eof}) {
639	# no progress can be made (not enough data and no data forthcoming)	882	# no progress can be made (not enough data and no data forthcoming)
640	return $self->_error (&Errno::EPIPE, 1);	883	$self->_error (&Errno::EPIPE, 1), return;
641	}	884	}
642		885
643	unshift @{ $self->{_queue} }, $cb;	886	unshift @{ $self->{_queue} }, $cb;
644	return;	887	last;
645	}	888	}
646	} elsif ($self->{on_read}) {	889	} elsif ($self->{on_read}) {
		890	last unless $len;
		891
647	$self->{on_read}($self);	892	$self->{on_read}($self);
648		893
649	if (	894	if (
650	$self->{_eof} # if no further data will arrive
651	&& $len == length $self->{rbuf} # and no data has been consumed	895	$len == length $self->{rbuf} # if no data has been consumed
652	&& !@{ $self->{_queue} } # and the queue is still empty	896	&& !@{ $self->{_queue} } # and the queue is still empty
653	&& $self->{on_read} # and we still want to read data	897	&& $self->{on_read} # but we still have on_read
654	) {	898	) {
		899	# no further data will arrive
655	# then no progress can be made	900	# so no progress can be made
656	return $self->_error (&Errno::EPIPE, 1);	901	$self->_error (&Errno::EPIPE, 1), return
		902	if $self->{_eof};
		903
		904	last; # more data might arrive
657	}	905	}
658	} else {	906	} else {
659	# read side becomes idle	907	# read side becomes idle
660	delete $self->{_rw};	908	delete $self->{_rw} unless $self->{tls};
661	return;	909	last;
662	}	910	}
663	}	911	}
664		912
		913	if ($self->{_eof}) {
		914	if ($self->{on_eof}) {
665	$self->{on_eof}($self)	915	$self->{on_eof}($self)
666	if $self->{_eof} && $self->{on_eof};	916	} else {
		917	$self->_error (0, 1, "Unexpected end-of-file");
		918	}
		919	}
		920
		921	# may need to restart read watcher
		922	unless ($self->{_rw}) {
		923	$self->start_read
		924	if $self->{on_read} || @{ $self->{_queue} };
		925	}
667	}	926	}
668		927
669	=item $handle->on_read ($cb)	928	=item $handle->on_read ($cb)
670		929
671	This replaces the currently set C<on_read> callback, or clears it (when	930	This replaces the currently set C<on_read> callback, or clears it (when
…		…
676		935
677	sub on_read {	936	sub on_read {
678	my ($self, $cb) = @_;	937	my ($self, $cb) = @_;
679		938
680	$self->{on_read} = $cb;	939	$self->{on_read} = $cb;
		940	$self->_drain_rbuf if $cb && !$self->{_in_drain};
681	}	941	}
682		942
683	=item $handle->rbuf	943	=item $handle->rbuf
684		944
685	Returns the read buffer (as a modifiable lvalue).	945	Returns the read buffer (as a modifiable lvalue).
686		946
687	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	947	You can access the read buffer directly as the C<< ->{rbuf} >>
688	you want.	948	member, if you want. However, the only operation allowed on the
		949	read buffer (apart from looking at it) is removing data from its
		950	beginning. Otherwise modifying or appending to it is not allowed and will
		951	lead to hard-to-track-down bugs.
689		952
690	NOTE: The read buffer should only be used or modified if the C<on_read>,	953	NOTE: The read buffer should only be used or modified if the C<on_read>,
691	C<push_read> or C<unshift_read> methods are used. The other read methods	954	C<push_read> or C<unshift_read> methods are used. The other read methods
692	automatically manage the read buffer.	955	automatically manage the read buffer.
693		956
…		…
734	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	997	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
735	->($self, $cb, @_);	998	->($self, $cb, @_);
736	}	999	}
737		1000
738	push @{ $self->{_queue} }, $cb;	1001	push @{ $self->{_queue} }, $cb;
739	$self->_drain_rbuf;	1002	$self->_drain_rbuf unless $self->{_in_drain};
740	}	1003	}
741		1004
742	sub unshift_read {	1005	sub unshift_read {
743	my $self = shift;	1006	my $self = shift;
744	my $cb = pop;	1007	my $cb = pop;
…		…
750	->($self, $cb, @_);	1013	->($self, $cb, @_);
751	}	1014	}
752		1015
753		1016
754	unshift @{ $self->{_queue} }, $cb;	1017	unshift @{ $self->{_queue} }, $cb;
755	$self->_drain_rbuf;	1018	$self->_drain_rbuf unless $self->{_in_drain};
756	}	1019	}
757		1020
758	=item $handle->push_read (type => @args, $cb)	1021	=item $handle->push_read (type => @args, $cb)
759		1022
760	=item $handle->unshift_read (type => @args, $cb)	1023	=item $handle->unshift_read (type => @args, $cb)
…		…
790	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1053	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
791	1	1054	1
792	}	1055	}
793	};	1056	};
794		1057
795	# compatibility with older API
796	sub push_read_chunk {
797	$_[0]->push_read (chunk => $_[1], $_[2]);
798	}
799
800	sub unshift_read_chunk {
801	$_[0]->unshift_read (chunk => $_[1], $_[2]);
802	}
803
804	=item line => [$eol, ]$cb->($handle, $line, $eol)	1058	=item line => [$eol, ]$cb->($handle, $line, $eol)
805		1059
806	The callback will be called only once a full line (including the end of	1060	The callback will be called only once a full line (including the end of
807	line marker, C<$eol>) has been read. This line (excluding the end of line	1061	line marker, C<$eol>) has been read. This line (excluding the end of line
808	marker) will be passed to the callback as second argument (C<$line>), and	1062	marker) will be passed to the callback as second argument (C<$line>), and
…		…
823	=cut	1077	=cut
824		1078
825	register_read_type line => sub {	1079	register_read_type line => sub {
826	my ($self, $cb, $eol) = @_;	1080	my ($self, $cb, $eol) = @_;
827		1081
828	$eol = qr|(\015?\012)| if @_ < 3;	1082	if (@_ < 3) {
829	$eol = quotemeta $eol unless ref $eol;	1083	# this is more than twice as fast as the generic code below
830	$eol = qr|^(.*?)($eol)|s;
831
832	sub {	1084	sub {
833	$_[0]{rbuf} =~ s/$eol// or return;	1085	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
834		1086
835	$cb->($_[0], $1, $2);	1087	$cb->($_[0], $1, $2);
836	1
837	}
838	};
839
840	# compatibility with older API
841	sub push_read_line {
842	my $self = shift;
843	$self->push_read (line => @_);
844	}
845
846	sub unshift_read_line {
847	my $self = shift;
848	$self->unshift_read (line => @_);
849	}
850
851	=item netstring => $cb->($handle, $string)
852
853	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
854
855	Throws an error with C<$!> set to EBADMSG on format violations.
856
857	=cut
858
859	register_read_type netstring => sub {
860	my ($self, $cb) = @_;
861
862	sub {
863	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
864	if ($_[0]{rbuf} =~ /[^0-9]/) {
865	$self->_error (&Errno::EBADMSG);
866	}	1088	1
867	return;
868	}	1089	}
		1090	} else {
		1091	$eol = quotemeta $eol unless ref $eol;
		1092	$eol = qr|^(.*?)($eol)|s;
869		1093
870	my $len = $1;	1094	sub {
		1095	$_[0]{rbuf} =~ s/$eol// or return;
871		1096
872	$self->unshift_read (chunk => $len, sub {	1097	$cb->($_[0], $1, $2);
873	my $string = $_[1];
874	$_[0]->unshift_read (chunk => 1, sub {
875	if ($_[1] eq ",") {
876	$cb->($_[0], $string);
877	} else {
878	$self->_error (&Errno::EBADMSG);
879	}
880	});	1098	1
881	});	1099	}
882
883	1
884	}	1100	}
885	};	1101	};
886		1102
887	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)	1103	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
888		1104
…		…
952		1168
953	()	1169	()
954	}	1170	}
955	};	1171	};
956		1172
		1173	=item netstring => $cb->($handle, $string)
		1174
		1175	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1176
		1177	Throws an error with C<$!> set to EBADMSG on format violations.
		1178
		1179	=cut
		1180
		1181	register_read_type netstring => sub {
		1182	my ($self, $cb) = @_;
		1183
		1184	sub {
		1185	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1186	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1187	$self->_error (&Errno::EBADMSG);
		1188	}
		1189	return;
		1190	}
		1191
		1192	my $len = $1;
		1193
		1194	$self->unshift_read (chunk => $len, sub {
		1195	my $string = $_[1];
		1196	$_[0]->unshift_read (chunk => 1, sub {
		1197	if ($_[1] eq ",") {
		1198	$cb->($_[0], $string);
		1199	} else {
		1200	$self->_error (&Errno::EBADMSG);
		1201	}
		1202	});
		1203	});
		1204
		1205	1
		1206	}
		1207	};
		1208
		1209	=item packstring => $format, $cb->($handle, $string)
		1210
		1211	An octet string prefixed with an encoded length. The encoding C<$format>
		1212	uses the same format as a Perl C<pack> format, but must specify a single
		1213	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1214	optional C<!>, C<< < >> or C<< > >> modifier).
		1215
		1216	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1217	EPP uses a prefix of C<N> (4 octtes).
		1218
		1219	Example: read a block of data prefixed by its length in BER-encoded
		1220	format (very efficient).
		1221
		1222	$handle->push_read (packstring => "w", sub {
		1223	my ($handle, $data) = @_;
		1224	});
		1225
		1226	=cut
		1227
		1228	register_read_type packstring => sub {
		1229	my ($self, $cb, $format) = @_;
		1230
		1231	sub {
		1232	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1233	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1234	or return;
		1235
		1236	$format = length pack $format, $len;
		1237
		1238	# bypass unshift if we already have the remaining chunk
		1239	if ($format + $len <= length $_[0]{rbuf}) {
		1240	my $data = substr $_[0]{rbuf}, $format, $len;
		1241	substr $_[0]{rbuf}, 0, $format + $len, "";
		1242	$cb->($_[0], $data);
		1243	} else {
		1244	# remove prefix
		1245	substr $_[0]{rbuf}, 0, $format, "";
		1246
		1247	# read remaining chunk
		1248	$_[0]->unshift_read (chunk => $len, $cb);
		1249	}
		1250
		1251	1
		1252	}
		1253	};
		1254
957	=item json => $cb->($handle, $hash_or_arrayref)	1255	=item json => $cb->($handle, $hash_or_arrayref)
958		1256
959	Reads a JSON object or array, decodes it and passes it to the callback.	1257	Reads a JSON object or array, decodes it and passes it to the
		1258	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
960		1259
961	If a C<json> object was passed to the constructor, then that will be used	1260	If a C<json> object was passed to the constructor, then that will be used
962	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1261	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
963		1262
964	This read type uses the incremental parser available with JSON version	1263	This read type uses the incremental parser available with JSON version
…		…
971	the C<json> write type description, above, for an actual example.	1270	the C<json> write type description, above, for an actual example.
972		1271
973	=cut	1272	=cut
974		1273
975	register_read_type json => sub {	1274	register_read_type json => sub {
976	my ($self, $cb, $accept, $reject, $skip) = @_;	1275	my ($self, $cb) = @_;
977		1276
978	require JSON;	1277	my $json = $self->{json} ||=
		1278	eval { require JSON::XS; JSON::XS->new->utf8 }
		1279	|| do { require JSON; JSON->new->utf8 };
979		1280
980	my $data;	1281	my $data;
981	my $rbuf = \$self->{rbuf};	1282	my $rbuf = \$self->{rbuf};
982		1283
983	my $json = $self->{json} ||= JSON->new->utf8;
984
985	sub {	1284	sub {
986	my $ref = $json->incr_parse ($self->{rbuf});	1285	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
987		1286
988	if ($ref) {	1287	if ($ref) {
989	$self->{rbuf} = $json->incr_text;	1288	$self->{rbuf} = $json->incr_text;
990	$json->incr_text = "";	1289	$json->incr_text = "";
991	$cb->($self, $ref);	1290	$cb->($self, $ref);
992		1291
993	1	1292	1
		1293	} elsif ($@) {
		1294	# error case
		1295	$json->incr_skip;
		1296
		1297	$self->{rbuf} = $json->incr_text;
		1298	$json->incr_text = "";
		1299
		1300	$self->_error (&Errno::EBADMSG);
		1301
		1302	()
994	} else {	1303	} else {
995	$self->{rbuf} = "";	1304	$self->{rbuf} = "";
		1305
996	()	1306	()
997	}	1307	}
		1308	}
		1309	};
		1310
		1311	=item storable => $cb->($handle, $ref)
		1312
		1313	Deserialises a L<Storable> frozen representation as written by the
		1314	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1315	data).
		1316
		1317	Raises C<EBADMSG> error if the data could not be decoded.
		1318
		1319	=cut
		1320
		1321	register_read_type storable => sub {
		1322	my ($self, $cb) = @_;
		1323
		1324	require Storable;
		1325
		1326	sub {
		1327	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1328	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1329	or return;
		1330
		1331	my $format = length pack "w", $len;
		1332
		1333	# bypass unshift if we already have the remaining chunk
		1334	if ($format + $len <= length $_[0]{rbuf}) {
		1335	my $data = substr $_[0]{rbuf}, $format, $len;
		1336	substr $_[0]{rbuf}, 0, $format + $len, "";
		1337	$cb->($_[0], Storable::thaw ($data));
		1338	} else {
		1339	# remove prefix
		1340	substr $_[0]{rbuf}, 0, $format, "";
		1341
		1342	# read remaining chunk
		1343	$_[0]->unshift_read (chunk => $len, sub {
		1344	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1345	$cb->($_[0], $ref);
		1346	} else {
		1347	$self->_error (&Errno::EBADMSG);
		1348	}
		1349	});
		1350	}
		1351
		1352	1
998	}	1353	}
999	};	1354	};
1000		1355
1001	=back	1356	=back
1002		1357
…		…
1023	=item $handle->stop_read	1378	=item $handle->stop_read
1024		1379
1025	=item $handle->start_read	1380	=item $handle->start_read
1026		1381
1027	In rare cases you actually do not want to read anything from the	1382	In rare cases you actually do not want to read anything from the
1028	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1383	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
1029	any queued callbacks will be executed then. To start reading again, call	1384	any queued callbacks will be executed then. To start reading again, call
1030	C<start_read>.	1385	C<start_read>.
1031		1386
		1387	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1388	you change the C<on_read> callback or push/unshift a read callback, and it
		1389	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1390	there are any read requests in the queue.
		1391
		1392	These methods will have no effect when in TLS mode (as TLS doesn't support
		1393	half-duplex connections).
		1394
1032	=cut	1395	=cut
1033		1396
1034	sub stop_read {	1397	sub stop_read {
1035	my ($self) = @_;	1398	my ($self) = @_;
1036		1399
1037	delete $self->{_rw};	1400	delete $self->{_rw} unless $self->{tls};
1038	}	1401	}
1039		1402
1040	sub start_read {	1403	sub start_read {
1041	my ($self) = @_;	1404	my ($self) = @_;
1042		1405
1043	unless ($self->{_rw} || $self->{_eof}) {	1406	unless ($self->{_rw} || $self->{_eof}) {
1044	Scalar::Util::weaken $self;	1407	Scalar::Util::weaken $self;
1045		1408
1046	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1409	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1047	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1410	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1048	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1411	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1049		1412
1050	if ($len > 0) {	1413	if ($len > 0) {
1051	$self->{_activity} = AnyEvent->now;	1414	$self->{_activity} = AnyEvent->now;
1052		1415
1053	$self->{filter_r}	1416	if ($self->{tls}) {
1054	? $self->{filter_r}($self, $rbuf)	1417	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1055	: $self->_drain_rbuf;	1418
		1419	&_dotls ($self);
		1420	} else {
		1421	$self->_drain_rbuf unless $self->{_in_drain};
		1422	}
1056		1423
1057	} elsif (defined $len) {	1424	} elsif (defined $len) {
1058	delete $self->{_rw};	1425	delete $self->{_rw};
1059	$self->{_eof} = 1;	1426	$self->{_eof} = 1;
1060	$self->_drain_rbuf;	1427	$self->_drain_rbuf unless $self->{_in_drain};
1061		1428
1062	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1429	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1063	return $self->_error ($!, 1);	1430	return $self->_error ($!, 1);
1064	}	1431	}
1065	});	1432	});
1066	}	1433	}
1067	}	1434	}
1068		1435
		1436	our $ERROR_SYSCALL;
		1437	our $ERROR_WANT_READ;
		1438
		1439	sub _tls_error {
		1440	my ($self, $err) = @_;
		1441
		1442	return $self->_error ($!, 1)
		1443	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1444
		1445	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1446
		1447	# reduce error string to look less scary
		1448	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1449
		1450	if ($self->{_on_starttls}) {
		1451	(delete $self->{_on_starttls})->($self, undef, $err);
		1452	&_freetls;
		1453	} else {
		1454	&_freetls;
		1455	$self->_error (&Errno::EPROTO, 1, $err);
		1456	}
		1457	}
		1458
		1459	# poll the write BIO and send the data if applicable
		1460	# also decode read data if possible
		1461	# this is basiclaly our TLS state machine
		1462	# more efficient implementations are possible with openssl,
		1463	# but not with the buggy and incomplete Net::SSLeay.
1069	sub _dotls {	1464	sub _dotls {
1070	my ($self) = @_;	1465	my ($self) = @_;
1071		1466
		1467	my $tmp;
		1468
1072	if (length $self->{_tls_wbuf}) {	1469	if (length $self->{_tls_wbuf}) {
1073	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1470	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1074	substr $self->{_tls_wbuf}, 0, $len, "";	1471	substr $self->{_tls_wbuf}, 0, $tmp, "";
1075	}	1472	}
1076	}
1077		1473
		1474	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1475	return $self->_tls_error ($tmp)
		1476	if $tmp != $ERROR_WANT_READ
		1477	&& ($tmp != $ERROR_SYSCALL || $!);
		1478	}
		1479
		1480	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1481	unless (length $tmp) {
		1482	$self->{_on_starttls}
		1483	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1484	&_freetls;
		1485
		1486	if ($self->{on_stoptls}) {
		1487	$self->{on_stoptls}($self);
		1488	return;
		1489	} else {
		1490	# let's treat SSL-eof as we treat normal EOF
		1491	delete $self->{_rw};
		1492	$self->{_eof} = 1;
		1493	}
		1494	}
		1495
		1496	$self->{_tls_rbuf} .= $tmp;
		1497	$self->_drain_rbuf unless $self->{_in_drain};
		1498	$self->{tls} or return; # tls session might have gone away in callback
		1499	}
		1500
		1501	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1502	return $self->_tls_error ($tmp)
		1503	if $tmp != $ERROR_WANT_READ
		1504	&& ($tmp != $ERROR_SYSCALL || $!);
		1505
1078	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1506	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1079	$self->{wbuf} .= $buf;	1507	$self->{wbuf} .= $tmp;
1080	$self->_drain_wbuf;	1508	$self->_drain_wbuf;
1081	}	1509	}
1082		1510
1083	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {	1511	$self->{_on_starttls}
1084	$self->{rbuf} .= $buf;	1512	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1085	$self->_drain_rbuf;	1513	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1086	}
1087
1088	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1089
1090	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1091	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1092	return $self->_error ($!, 1);
1093	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1094	return $self->_error (&Errno::EIO, 1);
1095	}
1096
1097	# all others are fine for our purposes
1098	}
1099	}	1514	}
1100		1515
1101	=item $handle->starttls ($tls[, $tls_ctx])	1516	=item $handle->starttls ($tls[, $tls_ctx])
1102		1517
1103	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1518	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
…		…
1105	C<starttls>.	1520	C<starttls>.
1106		1521
1107	The first argument is the same as the C<tls> constructor argument (either	1522	The first argument is the same as the C<tls> constructor argument (either
1108	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1523	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1109		1524
1110	The second argument is the optional C<Net::SSLeay::CTX> object that is	1525	The second argument is the optional C<AnyEvent::TLS> object that is used
1111	used when AnyEvent::Handle has to create its own TLS connection object.	1526	when AnyEvent::Handle has to create its own TLS connection object, or
		1527	a hash reference with C<< key => value >> pairs that will be used to
		1528	construct a new context.
1112		1529
1113	The TLS connection object will end up in C<< $handle->{tls} >> after this	1530	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1114	call and can be used or changed to your liking. Note that the handshake	1531	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1115	might have already started when this function returns.	1532	changed to your liking. Note that the handshake might have already started
		1533	when this function returns.
1116		1534
		1535	If it an error to start a TLS handshake more than once per
		1536	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1537
1117	=cut	1538	=cut
		1539
		1540	our %TLS_CACHE; #TODO not yet documented, should we?
1118		1541
1119	sub starttls {	1542	sub starttls {
1120	my ($self, $ssl, $ctx) = @_;	1543	my ($self, $ssl, $ctx) = @_;
1121		1544
1122	$self->stoptls;	1545	require Net::SSLeay;
1123		1546
1124	if ($ssl eq "accept") {	1547	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1125	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1548	if $self->{tls};
1126	Net::SSLeay::set_accept_state ($ssl);	1549
1127	} elsif ($ssl eq "connect") {	1550	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1128	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1551	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1129	Net::SSLeay::set_connect_state ($ssl);	1552
		1553	$ctx ||= $self->{tls_ctx};
		1554
		1555	if ("HASH" eq ref $ctx) {
		1556	require AnyEvent::TLS;
		1557
		1558	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
		1559
		1560	if ($ctx->{cache}) {
		1561	my $key = $ctx+0;
		1562	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1563	} else {
		1564	$ctx = new AnyEvent::TLS %$ctx;
		1565	}
		1566	}
1130	}	1567
1131		1568	$self->{tls_ctx} = $ctx || TLS_CTX ();
1132	$self->{tls} = $ssl;	1569	$self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});
1133		1570
1134	# basically, this is deep magic (because SSL_read should have the same issues)	1571	# basically, this is deep magic (because SSL_read should have the same issues)
1135	# but the openssl maintainers basically said: "trust us, it just works".	1572	# but the openssl maintainers basically said: "trust us, it just works".
1136	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1573	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1137	# and mismaintained ssleay-module doesn't even offer them).	1574	# and mismaintained ssleay-module doesn't even offer them).
1138	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1575	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1576	#
		1577	# in short: this is a mess.
		1578	#
		1579	# note that we do not try to keep the length constant between writes as we are required to do.
		1580	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1581	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1582	# have identity issues in that area.
1139	Net::SSLeay::CTX_set_mode ($self->{tls},	1583	# Net::SSLeay::CTX_set_mode ($ssl,
1140	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1584	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1141	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1585	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1586	Net::SSLeay::CTX_set_mode ($ssl, 1|2);
1142		1587
1143	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1588	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1144	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1589	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1145		1590
1146	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1591	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1147		1592
1148	$self->{filter_w} = sub {	1593	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1149	$_[0]{_tls_wbuf} .= ${$_[1]};	1594	if $self->{on_starttls};
1150	&_dotls;	1595
1151	};	1596	&_dotls; # need to trigger the initial handshake
1152	$self->{filter_r} = sub {	1597	$self->start_read; # make sure we actually do read
1153	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1154	&_dotls;
1155	};
1156	}	1598	}
1157		1599
1158	=item $handle->stoptls	1600	=item $handle->stoptls
1159		1601
1160	Destroys the SSL connection, if any. Partial read or write data will be	1602	Shuts down the SSL connection - this makes a proper EOF handshake by
1161	lost.	1603	sending a close notify to the other side, but since OpenSSL doesn't
		1604	support non-blocking shut downs, it is not possible to re-use the stream
		1605	afterwards.
1162		1606
1163	=cut	1607	=cut
1164		1608
1165	sub stoptls {	1609	sub stoptls {
1166	my ($self) = @_;	1610	my ($self) = @_;
1167		1611
1168	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1612	if ($self->{tls}) {
		1613	Net::SSLeay::shutdown ($self->{tls});
1169		1614
1170	delete $self->{_rbio};	1615	&_dotls;
1171	delete $self->{_wbio};	1616
1172	delete $self->{_tls_wbuf};	1617	# # we don't give a shit. no, we do, but we can't. no...#d#
1173	delete $self->{filter_r};	1618	# # we, we... have to use openssl :/#d#
1174	delete $self->{filter_w};	1619	# &_freetls;#d#
		1620	}
		1621	}
		1622
		1623	sub _freetls {
		1624	my ($self) = @_;
		1625
		1626	return unless $self->{tls};
		1627
		1628	$self->{tls_ctx}->_put_session (delete $self->{tls});
		1629
		1630	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1175	}	1631	}
1176		1632
1177	sub DESTROY {	1633	sub DESTROY {
1178	my $self = shift;	1634	my ($self) = @_;
1179		1635
1180	$self->stoptls;	1636	&_freetls;
		1637
		1638	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1639
		1640	if ($linger && length $self->{wbuf}) {
		1641	my $fh = delete $self->{fh};
		1642	my $wbuf = delete $self->{wbuf};
		1643
		1644	my @linger;
		1645
		1646	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1647	my $len = syswrite $fh, $wbuf, length $wbuf;
		1648
		1649	if ($len > 0) {
		1650	substr $wbuf, 0, $len, "";
		1651	} else {
		1652	@linger = (); # end
		1653	}
		1654	});
		1655	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1656	@linger = ();
		1657	});
		1658	}
		1659	}
		1660
		1661	=item $handle->destroy
		1662
		1663	Shuts down the handle object as much as possible - this call ensures that
		1664	no further callbacks will be invoked and as many resources as possible
		1665	will be freed. You must not call any methods on the object afterwards.
		1666
		1667	Normally, you can just "forget" any references to an AnyEvent::Handle
		1668	object and it will simply shut down. This works in fatal error and EOF
		1669	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1670	callback, so when you want to destroy the AnyEvent::Handle object from
		1671	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1672	that case.
		1673
		1674	The handle might still linger in the background and write out remaining
		1675	data, as specified by the C<linger> option, however.
		1676
		1677	=cut
		1678
		1679	sub destroy {
		1680	my ($self) = @_;
		1681
		1682	$self->DESTROY;
		1683	%$self = ();
1181	}	1684	}
1182		1685
1183	=item AnyEvent::Handle::TLS_CTX	1686	=item AnyEvent::Handle::TLS_CTX
1184		1687
1185	This function creates and returns the Net::SSLeay::CTX object used by	1688	This function creates and returns the AnyEvent::TLS object used by default
1186	default for TLS mode.	1689	for TLS mode.
1187		1690
1188	The context is created like this:	1691	The context is created by calling L<AnyEvent::TLS> without any arguments.
1189
1190	Net::SSLeay::load_error_strings;
1191	Net::SSLeay::SSLeay_add_ssl_algorithms;
1192	Net::SSLeay::randomize;
1193
1194	my $CTX = Net::SSLeay::CTX_new;
1195
1196	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1197		1692
1198	=cut	1693	=cut
1199		1694
1200	our $TLS_CTX;	1695	our $TLS_CTX;
1201		1696
1202	sub TLS_CTX() {	1697	sub TLS_CTX() {
1203	$TLS_CTX || do {	1698	$TLS_CTX ||= do {
1204	require Net::SSLeay;	1699	require AnyEvent::TLS;
1205		1700
1206	Net::SSLeay::load_error_strings ();	1701	new AnyEvent::TLS
1207	Net::SSLeay::SSLeay_add_ssl_algorithms ();
1208	Net::SSLeay::randomize ();
1209
1210	$TLS_CTX = Net::SSLeay::CTX_new ();
1211
1212	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1213
1214	$TLS_CTX
1215	}	1702	}
1216	}	1703	}
1217		1704
1218	=back	1705	=back
		1706
		1707
		1708	=head1 NONFREQUENTLY ASKED QUESTIONS
		1709
		1710	=over 4
		1711
		1712	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1713	still get further invocations!
		1714
		1715	That's because AnyEvent::Handle keeps a reference to itself when handling
		1716	read or write callbacks.
		1717
		1718	It is only safe to "forget" the reference inside EOF or error callbacks,
		1719	from within all other callbacks, you need to explicitly call the C<<
		1720	->destroy >> method.
		1721
		1722	=item I get different callback invocations in TLS mode/Why can't I pause
		1723	reading?
		1724
		1725	Unlike, say, TCP, TLS connections do not consist of two independent
		1726	communication channels, one for each direction. Or put differently. The
		1727	read and write directions are not independent of each other: you cannot
		1728	write data unless you are also prepared to read, and vice versa.
		1729
		1730	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1731	callback invocations when you are not expecting any read data - the reason
		1732	is that AnyEvent::Handle always reads in TLS mode.
		1733
		1734	During the connection, you have to make sure that you always have a
		1735	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1736	connection (or when you no longer want to use it) you can call the
		1737	C<destroy> method.
		1738
		1739	=item How do I read data until the other side closes the connection?
		1740
		1741	If you just want to read your data into a perl scalar, the easiest way
		1742	to achieve this is by setting an C<on_read> callback that does nothing,
		1743	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1744	will be in C<$_[0]{rbuf}>:
		1745
		1746	$handle->on_read (sub { });
		1747	$handle->on_eof (undef);
		1748	$handle->on_error (sub {
		1749	my $data = delete $_[0]{rbuf};
		1750	undef $handle;
		1751	});
		1752
		1753	The reason to use C<on_error> is that TCP connections, due to latencies
		1754	and packets loss, might get closed quite violently with an error, when in
		1755	fact, all data has been received.
		1756
		1757	It is usually better to use acknowledgements when transferring data,
		1758	to make sure the other side hasn't just died and you got the data
		1759	intact. This is also one reason why so many internet protocols have an
		1760	explicit QUIT command.
		1761
		1762	=item I don't want to destroy the handle too early - how do I wait until
		1763	all data has been written?
		1764
		1765	After writing your last bits of data, set the C<on_drain> callback
		1766	and destroy the handle in there - with the default setting of
		1767	C<low_water_mark> this will be called precisely when all data has been
		1768	written to the socket:
		1769
		1770	$handle->push_write (...);
		1771	$handle->on_drain (sub {
		1772	warn "all data submitted to the kernel\n";
		1773	undef $handle;
		1774	});
		1775
		1776	If you just want to queue some data and then signal EOF to the other side,
		1777	consider using C<< ->push_shutdown >> instead.
		1778
		1779	=item I want to contact a TLS/SSL server, I don't care about security.
		1780
		1781	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		1782	simply connect to it and then create the AnyEvent::Handle with the C<tls>
		1783	parameter:
		1784
		1785	my $handle = new AnyEvent::Handle
		1786	fh => $fh,
		1787	tls => "connect",
		1788	on_error => sub { ... };
		1789
		1790	$handle->push_write (...);
		1791
		1792	=item I want to contact a TLS/SSL server, I do care about security.
		1793
		1794	Then you #x##TODO#
		1795
		1796
		1797
		1798	=back
		1799
1219		1800
1220	=head1 SUBCLASSING AnyEvent::Handle	1801	=head1 SUBCLASSING AnyEvent::Handle
1221		1802
1222	In many cases, you might want to subclass AnyEvent::Handle.	1803	In many cases, you might want to subclass AnyEvent::Handle.
1223		1804
…		…
1227	=over 4	1808	=over 4
1228		1809
1229	=item * all constructor arguments become object members.	1810	=item * all constructor arguments become object members.
1230		1811
1231	At least initially, when you pass a C<tls>-argument to the constructor it	1812	At least initially, when you pass a C<tls>-argument to the constructor it
1232	will end up in C<< $handle->{tls} >>. Those members might be changes or	1813	will end up in C<< $handle->{tls} >>. Those members might be changed or
1233	mutated later on (for example C<tls> will hold the TLS connection object).	1814	mutated later on (for example C<tls> will hold the TLS connection object).
1234		1815
1235	=item * other object member names are prefixed with an C<_>.	1816	=item * other object member names are prefixed with an C<_>.
1236		1817
1237	All object members not explicitly documented (internal use) are prefixed	1818	All object members not explicitly documented (internal use) are prefixed

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