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Revision 1.225 by root, Mon Sep 26 11:32:19 2011 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict qw(subs vars);
5
6	use AnyEvent ();
7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();
9	use Carp ();
10	use Fcntl ();
11	use Errno qw(EAGAIN EINTR);
12
13	=head1 NAME	1	=head1 NAME
14		2
15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17	=cut
18
19	our $VERSION = 4.82;
20		4
21	=head1 SYNOPSIS	5	=head1 SYNOPSIS
22		6
23	use AnyEvent;	7	use AnyEvent;
24	use AnyEvent::Handle;	8	use AnyEvent::Handle;
…		…
26	my $cv = AnyEvent->condvar;	10	my $cv = AnyEvent->condvar;
27		11
28	my $hdl; $hdl = new AnyEvent::Handle	12	my $hdl; $hdl = new AnyEvent::Handle
29	fh => \*STDIN,	13	fh => \*STDIN,
30	on_error => sub {	14	on_error => sub {
31	warn "got error $_[2]\n";	15	my ($hdl, $fatal, $msg) = @_;
		16	AE::log error => "got error $msg\n";
		17	$hdl->destroy;
32	$cv->send;	18	$cv->send;
33	);	19	};
34		20
35	# send some request line	21	# send some request line
36	$hdl->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
37		23
38	# read the response line	24	# read the response line
39	$hdl->push_read (line => sub {	25	$hdl->push_read (line => sub {
40	my ($hdl, $line) = @_;	26	my ($hdl, $line) = @_;
41	warn "got line <$line>\n";	27	say "got line <$line>";
42	$cv->send;	28	$cv->send;
43	});	29	});
44		30
45	$cv->recv;	31	$cv->recv;
46		32
47	=head1 DESCRIPTION	33	=head1 DESCRIPTION
48		34
49	This module is a helper module to make it easier to do event-based I/O on	35	This is a helper module to make it easier to do event-based I/O on
50	filehandles. For utility functions for doing non-blocking connects and accepts	36	stream-based filehandles (sockets, pipes, and other stream things).
51	on sockets see L<AnyEvent::Util>.
52		37
53	The L<AnyEvent::Intro> tutorial contains some well-documented	38	The L<AnyEvent::Intro> tutorial contains some well-documented
54	AnyEvent::Handle examples.	39	AnyEvent::Handle examples.
55		40
56	In the following, when the documentation refers to of "bytes" then this	41	In the following, where the documentation refers to "bytes", it means
57	means characters. As sysread and syswrite are used for all I/O, their	42	characters. As sysread and syswrite are used for all I/O, their
58	treatment of characters applies to this module as well.	43	treatment of characters applies to this module as well.
		44
		45	At the very minimum, you should specify C<fh> or C<connect>, and the
		46	C<on_error> callback.
59		47
60	All callbacks will be invoked with the handle object as their first	48	All callbacks will be invoked with the handle object as their first
61	argument.	49	argument.
62		50
		51	=cut
		52
		53	package AnyEvent::Handle;
		54
		55	use Scalar::Util ();
		56	use List::Util ();
		57	use Carp ();
		58	use Errno qw(EAGAIN EINTR);
		59
		60	use AnyEvent (); BEGIN { AnyEvent::common_sense }
		61	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		62
		63	our $VERSION = $AnyEvent::VERSION;
		64
		65	sub _load_func($) {
		66	my $func = $_[0];
		67
		68	unless (defined &$func) {
		69	my $pkg = $func;
		70	do {
		71	$pkg =~ s/::[^:]+$//
		72	or return;
		73	eval "require $pkg";
		74	} until defined &$func;
		75	}
		76
		77	\&$func
		78	}
		79
		80	sub MAX_READ_SIZE() { 131072 }
		81
63	=head1 METHODS	82	=head1 METHODS
64		83
65	=over 4	84	=over 4
66		85
67	=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...	86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
68		87
69	The constructor supports these arguments (all as C<< key => value >> pairs).	88	The constructor supports these arguments (all as C<< key => value >> pairs).
70		89
71	=over 4	90	=over 4
72		91
73	=item fh => $filehandle [MANDATORY]	92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
74		93
75	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
76
77	NOTE: The filehandle will be set to non-blocking mode (using	95	NOTE: The filehandle will be set to non-blocking mode (using
78	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
79	that mode.	97	that mode.
80		98
		99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
		100
		101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
		104
		105	You have to specify either this parameter, or C<fh>, above.
		106
		107	It is possible to push requests on the read and write queues, and modify
		108	properties of the stream, even while AnyEvent::Handle is connecting.
		109
		110	When this parameter is specified, then the C<on_prepare>,
		111	C<on_connect_error> and C<on_connect> callbacks will be called under the
		112	appropriate circumstances:
		113
		114	=over 4
		115
		116	=item on_prepare => $cb->($handle)
		117
		118	This (rarely used) callback is called before a new connection is
		119	attempted, but after the file handle has been created (you can access that
		120	file handle via C<< $handle->{fh} >>). It could be used to prepare the
		121	file handle with parameters required for the actual connect (as opposed to
		122	settings that can be changed when the connection is already established).
		123
		124	The return value of this callback should be the connect timeout value in
		125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
		126	default timeout is to be used).
		127
		128	=item on_connect => $cb->($handle, $host, $port, $retry->())
		129
		130	This callback is called when a connection has been successfully established.
		131
		132	The peer's numeric host and port (the socket peername) are passed as
		133	parameters, together with a retry callback.
		134
		135	If, for some reason, the handle is not acceptable, calling C<$retry>
		136	will continue with the next connection target (in case of multi-homed
		137	hosts or SRV records there can be multiple connection endpoints). At the
		138	time it is called the read and write queues, eof status, tls status and
		139	similar properties of the handle will have been reset.
		140
		141	In most cases, you should ignore the C<$retry> parameter.
		142
		143	=item on_connect_error => $cb->($handle, $message)
		144
		145	This callback is called when the connection could not be
		146	established. C<$!> will contain the relevant error code, and C<$message> a
		147	message describing it (usually the same as C<"$!">).
		148
		149	If this callback isn't specified, then C<on_error> will be called with a
		150	fatal error instead.
		151
		152	=back
		153
		154	=item on_error => $cb->($handle, $fatal, $message)
		155
		156	This is the error callback, which is called when, well, some error
		157	occured, such as not being able to resolve the hostname, failure to
		158	connect, or a read error.
		159
		160	Some errors are fatal (which is indicated by C<$fatal> being true). On
		161	fatal errors the handle object will be destroyed (by a call to C<< ->
		162	destroy >>) after invoking the error callback (which means you are free to
		163	examine the handle object). Examples of fatal errors are an EOF condition
		164	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		165	cases where the other side can close the connection at will, it is
		166	often easiest to not report C<EPIPE> errors in this callback.
		167
		168	AnyEvent::Handle tries to find an appropriate error code for you to check
		169	against, but in some cases (TLS errors), this does not work well. It is
		170	recommended to always output the C<$message> argument in human-readable
		171	error messages (it's usually the same as C<"$!">).
		172
		173	Non-fatal errors can be retried by returning, but it is recommended
		174	to simply ignore this parameter and instead abondon the handle object
		175	when this callback is invoked. Examples of non-fatal errors are timeouts
		176	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		177
		178	On entry to the callback, the value of C<$!> contains the operating
		179	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		180	C<EPROTO>).
		181
		182	While not mandatory, it is I<highly> recommended to set this callback, as
		183	you will not be notified of errors otherwise. The default just calls
		184	C<croak>.
		185
		186	=item on_read => $cb->($handle)
		187
		188	This sets the default read callback, which is called when data arrives
		189	and no read request is in the queue (unlike read queue callbacks, this
		190	callback will only be called when at least one octet of data is in the
		191	read buffer).
		192
		193	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		194	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		195	must not enlarge or modify the read buffer, you can only remove data at
		196	the beginning from it.
		197
		198	You can also call C<< ->push_read (...) >> or any other function that
		199	modifies the read queue. Or do both. Or ...
		200
		201	When an EOF condition is detected, AnyEvent::Handle will first try to
		202	feed all the remaining data to the queued callbacks and C<on_read> before
		203	calling the C<on_eof> callback. If no progress can be made, then a fatal
		204	error will be raised (with C<$!> set to C<EPIPE>).
		205
		206	Note that, unlike requests in the read queue, an C<on_read> callback
		207	doesn't mean you I<require> some data: if there is an EOF and there
		208	are outstanding read requests then an error will be flagged. With an
		209	C<on_read> callback, the C<on_eof> callback will be invoked.
		210
81	=item on_eof => $cb->($handle)	211	=item on_eof => $cb->($handle)
82		212
83	Set the callback to be called when an end-of-file condition is detected,	213	Set the callback to be called when an end-of-file condition is detected,
84	i.e. in the case of a socket, when the other side has closed the	214	i.e. in the case of a socket, when the other side has closed the
85	connection cleanly.	215	connection cleanly, and there are no outstanding read requests in the
		216	queue (if there are read requests, then an EOF counts as an unexpected
		217	connection close and will be flagged as an error).
86		218
87	For sockets, this just means that the other side has stopped sending data,	219	For sockets, this just means that the other side has stopped sending data,
88	you can still try to write data, and, in fact, one can return from the EOF	220	you can still try to write data, and, in fact, one can return from the EOF
89	callback and continue writing data, as only the read part has been shut	221	callback and continue writing data, as only the read part has been shut
90	down.	222	down.
91		223
92	While not mandatory, it is I<highly> recommended to set an EOF callback,
93	otherwise you might end up with a closed socket while you are still
94	waiting for data.
95
96	If an EOF condition has been detected but no C<on_eof> callback has been	224	If an EOF condition has been detected but no C<on_eof> callback has been
97	set, then a fatal error will be raised with C<$!> set to <0>.	225	set, then a fatal error will be raised with C<$!> set to <0>.
98		226
99	=item on_error => $cb->($handle, $fatal, $message)
100
101	This is the error callback, which is called when, well, some error
102	occured, such as not being able to resolve the hostname, failure to
103	connect or a read error.
104
105	Some errors are fatal (which is indicated by C<$fatal> being true). On
106	fatal errors the handle object will be destroyed (by a call to C<< ->
107	destroy >>) after invoking the error callback (which means you are free to
108	examine the handle object). Examples of fatal errors are an EOF condition
109	with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors.
110
111	AnyEvent::Handle tries to find an appropriate error code for you to check
112	against, but in some cases (TLS errors), this does not work well. It is
113	recommended to always output the C<$message> argument in human-readable
114	error messages (it's usually the same as C<"$!">).
115
116	Non-fatal errors can be retried by simply returning, but it is recommended
117	to simply ignore this parameter and instead abondon the handle object
118	when this callback is invoked. Examples of non-fatal errors are timeouts
119	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
120
121	On callback entrance, the value of C<$!> contains the operating system
122	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
123	C<EPROTO>).
124
125	While not mandatory, it is I<highly> recommended to set this callback, as
126	you will not be notified of errors otherwise. The default simply calls
127	C<croak>.
128
129	=item on_read => $cb->($handle)
130
131	This sets the default read callback, which is called when data arrives
132	and no read request is in the queue (unlike read queue callbacks, this
133	callback will only be called when at least one octet of data is in the
134	read buffer).
135
136	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
137	method or access the C<< $handle->{rbuf} >> member directly. Note that you
138	must not enlarge or modify the read buffer, you can only remove data at
139	the beginning from it.
140
141	When an EOF condition is detected then AnyEvent::Handle will first try to
142	feed all the remaining data to the queued callbacks and C<on_read> before
143	calling the C<on_eof> callback. If no progress can be made, then a fatal
144	error will be raised (with C<$!> set to C<EPIPE>).
145
146	=item on_drain => $cb->($handle)	227	=item on_drain => $cb->($handle)
147		228
148	This sets the callback that is called when the write buffer becomes empty	229	This sets the callback that is called when the write buffer becomes empty
149	(or when the callback is set and the buffer is empty already).	230	(or immediately if the buffer is empty already).
150		231
151	To append to the write buffer, use the C<< ->push_write >> method.	232	To append to the write buffer, use the C<< ->push_write >> method.
152		233
153	This callback is useful when you don't want to put all of your write data	234	This callback is useful when you don't want to put all of your write data
154	into the queue at once, for example, when you want to write the contents	235	into the queue at once, for example, when you want to write the contents
…		…
156	memory and push it into the queue, but instead only read more data from	237	memory and push it into the queue, but instead only read more data from
157	the file when the write queue becomes empty.	238	the file when the write queue becomes empty.
158		239
159	=item timeout => $fractional_seconds	240	=item timeout => $fractional_seconds
160		241
		242	=item rtimeout => $fractional_seconds
		243
		244	=item wtimeout => $fractional_seconds
		245
161	If non-zero, then this enables an "inactivity" timeout: whenever this many	246	If non-zero, then these enables an "inactivity" timeout: whenever this
162	seconds pass without a successful read or write on the underlying file	247	many seconds pass without a successful read or write on the underlying
163	handle, the C<on_timeout> callback will be invoked (and if that one is	248	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
164	missing, a non-fatal C<ETIMEDOUT> error will be raised).	249	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		250	error will be raised).
165		251
		252	There are three variants of the timeouts that work independently of each
		253	other, for both read and write (triggered when nothing was read I<OR>
		254	written), just read (triggered when nothing was read), and just write:
		255	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		256	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		257	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		258
166	Note that timeout processing is also active when you currently do not have	259	Note that timeout processing is active even when you do not have any
167	any outstanding read or write requests: If you plan to keep the connection	260	outstanding read or write requests: If you plan to keep the connection
168	idle then you should disable the timout temporarily or ignore the timeout	261	idle then you should disable the timeout temporarily or ignore the
169	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply	262	timeout in the corresponding C<on_timeout> callback, in which case
170	restart the timeout.	263	AnyEvent::Handle will simply restart the timeout.
171		264
172	Zero (the default) disables this timeout.	265	Zero (the default) disables the corresponding timeout.
173		266
174	=item on_timeout => $cb->($handle)	267	=item on_timeout => $cb->($handle)
		268
		269	=item on_rtimeout => $cb->($handle)
		270
		271	=item on_wtimeout => $cb->($handle)
175		272
176	Called whenever the inactivity timeout passes. If you return from this	273	Called whenever the inactivity timeout passes. If you return from this
177	callback, then the timeout will be reset as if some activity had happened,	274	callback, then the timeout will be reset as if some activity had happened,
178	so this condition is not fatal in any way.	275	so this condition is not fatal in any way.
179		276
…		…
187	be configured to accept only so-and-so much data that it cannot act on	284	be configured to accept only so-and-so much data that it cannot act on
188	(for example, when expecting a line, an attacker could send an unlimited	285	(for example, when expecting a line, an attacker could send an unlimited
189	amount of data without a callback ever being called as long as the line	286	amount of data without a callback ever being called as long as the line
190	isn't finished).	287	isn't finished).
191		288
		289	=item wbuf_max => <bytes>
		290
		291	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		292	when the write buffer ever (strictly) exceeds this size. This is useful to
		293	avoid some forms of denial-of-service attacks.
		294
		295	Although the units of this parameter is bytes, this is the I<raw> number
		296	of bytes not yet accepted by the kernel. This can make a difference when
		297	you e.g. use TLS, as TLS typically makes your write data larger (but it
		298	can also make it smaller due to compression).
		299
		300	As an example of when this limit is useful, take a chat server that sends
		301	chat messages to a client. If the client does not read those in a timely
		302	manner then the send buffer in the server would grow unbounded.
		303
192	=item autocork => <boolean>	304	=item autocork => <boolean>
193		305
194	When disabled (the default), then C<push_write> will try to immediately	306	When disabled (the default), C<push_write> will try to immediately
195	write the data to the handle, if possible. This avoids having to register	307	write the data to the handle if possible. This avoids having to register
196	a write watcher and wait for the next event loop iteration, but can	308	a write watcher and wait for the next event loop iteration, but can
197	be inefficient if you write multiple small chunks (on the wire, this	309	be inefficient if you write multiple small chunks (on the wire, this
198	disadvantage is usually avoided by your kernel's nagle algorithm, see	310	disadvantage is usually avoided by your kernel's nagle algorithm, see
199	C<no_delay>, but this option can save costly syscalls).	311	C<no_delay>, but this option can save costly syscalls).
200		312
201	When enabled, then writes will always be queued till the next event loop	313	When enabled, writes will always be queued till the next event loop
202	iteration. This is efficient when you do many small writes per iteration,	314	iteration. This is efficient when you do many small writes per iteration,
203	but less efficient when you do a single write only per iteration (or when	315	but less efficient when you do a single write only per iteration (or when
204	the write buffer often is full). It also increases write latency.	316	the write buffer often is full). It also increases write latency.
205		317
206	=item no_delay => <boolean>	318	=item no_delay => <boolean>
…		…
210	the Nagle algorithm, and usually it is beneficial.	322	the Nagle algorithm, and usually it is beneficial.
211		323
212	In some situations you want as low a delay as possible, which can be	324	In some situations you want as low a delay as possible, which can be
213	accomplishd by setting this option to a true value.	325	accomplishd by setting this option to a true value.
214		326
215	The default is your opertaing system's default behaviour (most likely	327	The default is your operating system's default behaviour (most likely
216	enabled), this option explicitly enables or disables it, if possible.	328	enabled). This option explicitly enables or disables it, if possible.
		329
		330	=item keepalive => <boolean>
		331
		332	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		333	normally, TCP connections have no time-out once established, so TCP
		334	connections, once established, can stay alive forever even when the other
		335	side has long gone. TCP keepalives are a cheap way to take down long-lived
		336	TCP connections when the other side becomes unreachable. While the default
		337	is OS-dependent, TCP keepalives usually kick in after around two hours,
		338	and, if the other side doesn't reply, take down the TCP connection some 10
		339	to 15 minutes later.
		340
		341	It is harmless to specify this option for file handles that do not support
		342	keepalives, and enabling it on connections that are potentially long-lived
		343	is usually a good idea.
		344
		345	=item oobinline => <boolean>
		346
		347	BSD majorly fucked up the implementation of TCP urgent data. The result
		348	is that almost no OS implements TCP according to the specs, and every OS
		349	implements it slightly differently.
		350
		351	If you want to handle TCP urgent data, then setting this flag (the default
		352	is enabled) gives you the most portable way of getting urgent data, by
		353	putting it into the stream.
		354
		355	Since BSD emulation of OOB data on top of TCP's urgent data can have
		356	security implications, AnyEvent::Handle sets this flag automatically
		357	unless explicitly specified. Note that setting this flag after
		358	establishing a connection I<may> be a bit too late (data loss could
		359	already have occured on BSD systems), but at least it will protect you
		360	from most attacks.
217		361
218	=item read_size => <bytes>	362	=item read_size => <bytes>
219		363
220	The default read block size (the amount of bytes this module will	364	The initial read block size, the number of bytes this module will try
221	try to read during each loop iteration, which affects memory	365	to read during each loop iteration. Each handle object will consume
222	requirements). Default: C<8192>.	366	at least this amount of memory for the read buffer as well, so when
		367	handling many connections watch out for memory requirements). See also
		368	C<max_read_size>. Default: C<2048>.
		369
		370	=item max_read_size => <bytes>
		371
		372	The maximum read buffer size used by the dynamic adjustment
		373	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		374	one go it will double C<read_size> up to the maximum given by this
		375	option. Default: C<131072> or C<read_size>, whichever is higher.
223		376
224	=item low_water_mark => <bytes>	377	=item low_water_mark => <bytes>
225		378
226	Sets the amount of bytes (default: C<0>) that make up an "empty" write	379	Sets the number of bytes (default: C<0>) that make up an "empty" write
227	buffer: If the write reaches this size or gets even samller it is	380	buffer: If the buffer reaches this size or gets even samller it is
228	considered empty.	381	considered empty.
229		382
230	Sometimes it can be beneficial (for performance reasons) to add data to	383	Sometimes it can be beneficial (for performance reasons) to add data to
231	the write buffer before it is fully drained, but this is a rare case, as	384	the write buffer before it is fully drained, but this is a rare case, as
232	the operating system kernel usually buffers data as well, so the default	385	the operating system kernel usually buffers data as well, so the default
233	is good in almost all cases.	386	is good in almost all cases.
234		387
235	=item linger => <seconds>	388	=item linger => <seconds>
236		389
237	If non-zero (default: C<3600>), then the destructor of the	390	If this is non-zero (default: C<3600>), the destructor of the
238	AnyEvent::Handle object will check whether there is still outstanding	391	AnyEvent::Handle object will check whether there is still outstanding
239	write data and will install a watcher that will write this data to the	392	write data and will install a watcher that will write this data to the
240	socket. No errors will be reported (this mostly matches how the operating	393	socket. No errors will be reported (this mostly matches how the operating
241	system treats outstanding data at socket close time).	394	system treats outstanding data at socket close time).
242		395
…		…
249	A string used to identify the remote site - usually the DNS hostname	402	A string used to identify the remote site - usually the DNS hostname
250	(I<not> IDN!) used to create the connection, rarely the IP address.	403	(I<not> IDN!) used to create the connection, rarely the IP address.
251		404
252	Apart from being useful in error messages, this string is also used in TLS	405	Apart from being useful in error messages, this string is also used in TLS
253	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This	406	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
254	verification will be skipped when C<peername> is not specified or	407	verification will be skipped when C<peername> is not specified or is
255	C<undef>.	408	C<undef>.
256		409
257	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	410	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
258		411
259	When this parameter is given, it enables TLS (SSL) mode, that means	412	When this parameter is given, it enables TLS (SSL) mode, that means
260	AnyEvent will start a TLS handshake as soon as the conenction has been	413	AnyEvent will start a TLS handshake as soon as the connection has been
261	established and will transparently encrypt/decrypt data afterwards.	414	established and will transparently encrypt/decrypt data afterwards.
262		415
263	All TLS protocol errors will be signalled as C<EPROTO>, with an	416	All TLS protocol errors will be signalled as C<EPROTO>, with an
264	appropriate error message.	417	appropriate error message.
265		418
…		…
285	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,	438	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
286	passing in the wrong integer will lead to certain crash. This most often	439	passing in the wrong integer will lead to certain crash. This most often
287	happens when one uses a stylish C<< tls => 1 >> and is surprised about the	440	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
288	segmentation fault.	441	segmentation fault.
289		442
290	See the C<< ->starttls >> method for when need to start TLS negotiation later.	443	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
291		444
292	=item tls_ctx => $anyevent_tls	445	=item tls_ctx => $anyevent_tls
293		446
294	Use the given C<AnyEvent::TLS> object to create the new TLS connection	447	Use the given C<AnyEvent::TLS> object to create the new TLS connection
295	(unless a connection object was specified directly). If this parameter is	448	(unless a connection object was specified directly). If this
296	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	449	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		450	C<AnyEvent::Handle::TLS_CTX>.
297		451
298	Instead of an object, you can also specify a hash reference with C<< key	452	Instead of an object, you can also specify a hash reference with C<< key
299	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a	453	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
300	new TLS context object.	454	new TLS context object.
301		455
…		…
310		464
311	TLS handshake failures will not cause C<on_error> to be invoked when this	465	TLS handshake failures will not cause C<on_error> to be invoked when this
312	callback is in effect, instead, the error message will be passed to C<on_starttls>.	466	callback is in effect, instead, the error message will be passed to C<on_starttls>.
313		467
314	Without this callback, handshake failures lead to C<on_error> being	468	Without this callback, handshake failures lead to C<on_error> being
315	called, as normal.	469	called as usual.
316		470
317	Note that you cannot call C<starttls> right again in this callback. If you	471	Note that you cannot just call C<starttls> again in this callback. If you
318	need to do that, start an zero-second timer instead whose callback can	472	need to do that, start an zero-second timer instead whose callback can
319	then call C<< ->starttls >> again.	473	then call C<< ->starttls >> again.
320		474
321	=item on_stoptls => $cb->($handle)	475	=item on_stoptls => $cb->($handle)
322		476
…		…
348		502
349	sub new {	503	sub new {
350	my $class = shift;	504	my $class = shift;
351	my $self = bless { @_ }, $class;	505	my $self = bless { @_ }, $class;
352		506
353	$self->{fh} or Carp::croak "mandatory argument fh is missing";	507	if ($self->{fh}) {
		508	$self->_start;
		509	return unless $self->{fh}; # could be gone by now
		510
		511	} elsif ($self->{connect}) {
		512	require AnyEvent::Socket;
		513
		514	$self->{peername} = $self->{connect}[0]
		515	unless exists $self->{peername};
		516
		517	$self->{_skip_drain_rbuf} = 1;
		518
		519	{
		520	Scalar::Util::weaken (my $self = $self);
		521
		522	$self->{_connect} =
		523	AnyEvent::Socket::tcp_connect (
		524	$self->{connect}[0],
		525	$self->{connect}[1],
		526	sub {
		527	my ($fh, $host, $port, $retry) = @_;
		528
		529	delete $self->{_connect}; # no longer needed
		530
		531	if ($fh) {
		532	$self->{fh} = $fh;
		533
		534	delete $self->{_skip_drain_rbuf};
		535	$self->_start;
		536
		537	$self->{on_connect}
		538	and $self->{on_connect}($self, $host, $port, sub {
		539	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		540	$self->{_skip_drain_rbuf} = 1;
		541	&$retry;
		542	});
		543
		544	} else {
		545	if ($self->{on_connect_error}) {
		546	$self->{on_connect_error}($self, "$!");
		547	$self->destroy if $self;
		548	} else {
		549	$self->_error ($!, 1);
		550	}
		551	}
		552	},
		553	sub {
		554	local $self->{fh} = $_[0];
		555
		556	$self->{on_prepare}
		557	? $self->{on_prepare}->($self)
		558	: ()
		559	}
		560	);
		561	}
		562
		563	} else {
		564	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		565	}
		566
		567	$self
		568	}
		569
		570	sub _start {
		571	my ($self) = @_;
		572
		573	# too many clueless people try to use udp and similar sockets
		574	# with AnyEvent::Handle, do them a favour.
		575	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		576	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		577	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
354		578
355	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	579	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
356		580
		581	$self->{_activity} =
		582	$self->{_ractivity} =
357	$self->{_activity} = AnyEvent->now;	583	$self->{_wactivity} = AE::now;
358	$self->_timeout;
359		584
		585	$self->{read_size} ||= 2048;
		586	$self->{max_read_size} = $self->{read_size}
		587	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		588
		589	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		590	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		591	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		592
360	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};	593	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		594	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
361		595
		596	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		597
362	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})	598	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
363	if $self->{tls};	599	if $self->{tls};
364		600
365	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	601	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
366		602
367	$self->start_read	603	$self->start_read
368	if $self->{on_read};	604	if $self->{on_read} || @{ $self->{_queue} };
369		605
370	$self->{fh} && $self	606	$self->_drain_wbuf;
371	}	607	}
372
373	#sub _shutdown {
374	# my ($self) = @_;
375	#
376	# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
377	# $self->{_eof} = 1; # tell starttls et. al to stop trying
378	#
379	# &_freetls;
380	#}
381		608
382	sub _error {	609	sub _error {
383	my ($self, $errno, $fatal, $message) = @_;	610	my ($self, $errno, $fatal, $message) = @_;
384		611
385	$! = $errno;	612	$! = $errno;
386	$message ||= "$!";	613	$message ||= "$!";
387		614
388	if ($self->{on_error}) {	615	if ($self->{on_error}) {
389	$self->{on_error}($self, $fatal, $message);	616	$self->{on_error}($self, $fatal, $message);
390	$self->destroy;	617	$self->destroy if $fatal;
391	} elsif ($self->{fh}) {	618	} elsif ($self->{fh} || $self->{connect}) {
392	$self->destroy;	619	$self->destroy;
393	Carp::croak "AnyEvent::Handle uncaught error: $message";	620	Carp::croak "AnyEvent::Handle uncaught error: $message";
394	}	621	}
395	}	622	}
396		623
…		…
422	$_[0]{on_eof} = $_[1];	649	$_[0]{on_eof} = $_[1];
423	}	650	}
424		651
425	=item $handle->on_timeout ($cb)	652	=item $handle->on_timeout ($cb)
426		653
427	Replace the current C<on_timeout> callback, or disables the callback (but	654	=item $handle->on_rtimeout ($cb)
428	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
429	argument and method.
430		655
431	=cut	656	=item $handle->on_wtimeout ($cb)
432		657
433	sub on_timeout {	658	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
434	$_[0]{on_timeout} = $_[1];	659	callback, or disables the callback (but not the timeout) if C<$cb> =
435	}	660	C<undef>. See the C<timeout> constructor argument and method.
		661
		662	=cut
		663
		664	# see below
436		665
437	=item $handle->autocork ($boolean)	666	=item $handle->autocork ($boolean)
438		667
439	Enables or disables the current autocork behaviour (see C<autocork>	668	Enables or disables the current autocork behaviour (see C<autocork>
440	constructor argument). Changes will only take effect on the next write.	669	constructor argument). Changes will only take effect on the next write.
…		…
453	=cut	682	=cut
454		683
455	sub no_delay {	684	sub no_delay {
456	$_[0]{no_delay} = $_[1];	685	$_[0]{no_delay} = $_[1];
457		686
		687	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		688	if $_[0]{fh};
		689	}
		690
		691	=item $handle->keepalive ($boolean)
		692
		693	Enables or disables the C<keepalive> setting (see constructor argument of
		694	the same name for details).
		695
		696	=cut
		697
		698	sub keepalive {
		699	$_[0]{keepalive} = $_[1];
		700
458	eval {	701	eval {
459	local $SIG{__DIE__};	702	local $SIG{__DIE__};
460	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];	703	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		704	if $_[0]{fh};
		705	};
		706	}
		707
		708	=item $handle->oobinline ($boolean)
		709
		710	Enables or disables the C<oobinline> setting (see constructor argument of
		711	the same name for details).
		712
		713	=cut
		714
		715	sub oobinline {
		716	$_[0]{oobinline} = $_[1];
		717
		718	eval {
		719	local $SIG{__DIE__};
		720	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		721	if $_[0]{fh};
		722	};
		723	}
		724
		725	=item $handle->keepalive ($boolean)
		726
		727	Enables or disables the C<keepalive> setting (see constructor argument of
		728	the same name for details).
		729
		730	=cut
		731
		732	sub keepalive {
		733	$_[0]{keepalive} = $_[1];
		734
		735	eval {
		736	local $SIG{__DIE__};
		737	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		738	if $_[0]{fh};
461	};	739	};
462	}	740	}
463		741
464	=item $handle->on_starttls ($cb)	742	=item $handle->on_starttls ($cb)
465		743
…		…
475		753
476	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).	754	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
477		755
478	=cut	756	=cut
479		757
480	sub on_starttls {	758	sub on_stoptls {
481	$_[0]{on_stoptls} = $_[1];	759	$_[0]{on_stoptls} = $_[1];
482	}	760	}
483		761
		762	=item $handle->rbuf_max ($max_octets)
		763
		764	Configures the C<rbuf_max> setting (C<undef> disables it).
		765
		766	=item $handle->wbuf_max ($max_octets)
		767
		768	Configures the C<wbuf_max> setting (C<undef> disables it).
		769
		770	=cut
		771
		772	sub rbuf_max {
		773	$_[0]{rbuf_max} = $_[1];
		774	}
		775
		776	sub wbuf_max {
		777	$_[0]{wbuf_max} = $_[1];
		778	}
		779
484	#############################################################################	780	#############################################################################
485		781
486	=item $handle->timeout ($seconds)	782	=item $handle->timeout ($seconds)
487		783
		784	=item $handle->rtimeout ($seconds)
		785
		786	=item $handle->wtimeout ($seconds)
		787
488	Configures (or disables) the inactivity timeout.	788	Configures (or disables) the inactivity timeout.
489		789
490	=cut	790	The timeout will be checked instantly, so this method might destroy the
		791	handle before it returns.
491		792
492	sub timeout {	793	=item $handle->timeout_reset
		794
		795	=item $handle->rtimeout_reset
		796
		797	=item $handle->wtimeout_reset
		798
		799	Reset the activity timeout, as if data was received or sent.
		800
		801	These methods are cheap to call.
		802
		803	=cut
		804
		805	for my $dir ("", "r", "w") {
		806	my $timeout = "${dir}timeout";
		807	my $tw = "_${dir}tw";
		808	my $on_timeout = "on_${dir}timeout";
		809	my $activity = "_${dir}activity";
		810	my $cb;
		811
		812	*$on_timeout = sub {
		813	$_[0]{$on_timeout} = $_[1];
		814	};
		815
		816	*$timeout = sub {
493	my ($self, $timeout) = @_;	817	my ($self, $new_value) = @_;
494		818
		819	$new_value >= 0
		820	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		821
495	$self->{timeout} = $timeout;	822	$self->{$timeout} = $new_value;
496	$self->_timeout;	823	delete $self->{$tw}; &$cb;
497	}	824	};
498		825
		826	*{"${dir}timeout_reset"} = sub {
		827	$_[0]{$activity} = AE::now;
		828	};
		829
		830	# main workhorse:
499	# reset the timeout watcher, as neccessary	831	# reset the timeout watcher, as neccessary
500	# also check for time-outs	832	# also check for time-outs
501	sub _timeout {	833	$cb = sub {
502	my ($self) = @_;	834	my ($self) = @_;
503		835
504	if ($self->{timeout}) {	836	if ($self->{$timeout} && $self->{fh}) {
505	my $NOW = AnyEvent->now;	837	my $NOW = AE::now;
506		838
507	# when would the timeout trigger?	839	# when would the timeout trigger?
508	my $after = $self->{_activity} + $self->{timeout} - $NOW;	840	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
509		841
510	# now or in the past already?	842	# now or in the past already?
511	if ($after <= 0) {	843	if ($after <= 0) {
512	$self->{_activity} = $NOW;	844	$self->{$activity} = $NOW;
513		845
514	if ($self->{on_timeout}) {	846	if ($self->{$on_timeout}) {
515	$self->{on_timeout}($self);	847	$self->{$on_timeout}($self);
516	} else {	848	} else {
517	$self->_error (&Errno::ETIMEDOUT);	849	$self->_error (Errno::ETIMEDOUT);
		850	}
		851
		852	# callback could have changed timeout value, optimise
		853	return unless $self->{$timeout};
		854
		855	# calculate new after
		856	$after = $self->{$timeout};
518	}	857	}
519		858
520	# callback could have changed timeout value, optimise	859	Scalar::Util::weaken $self;
521	return unless $self->{timeout};	860	return unless $self; # ->error could have destroyed $self
522		861
523	# calculate new after	862	$self->{$tw} ||= AE::timer $after, 0, sub {
524	$after = $self->{timeout};	863	delete $self->{$tw};
		864	$cb->($self);
		865	};
		866	} else {
		867	delete $self->{$tw};
525	}	868	}
526
527	Scalar::Util::weaken $self;
528	return unless $self; # ->error could have destroyed $self
529
530	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
531	delete $self->{_tw};
532	$self->_timeout;
533	});
534	} else {
535	delete $self->{_tw};
536	}	869	}
537	}	870	}
538		871
539	#############################################################################	872	#############################################################################
540		873
…		…
556	=item $handle->on_drain ($cb)	889	=item $handle->on_drain ($cb)
557		890
558	Sets the C<on_drain> callback or clears it (see the description of	891	Sets the C<on_drain> callback or clears it (see the description of
559	C<on_drain> in the constructor).	892	C<on_drain> in the constructor).
560		893
		894	This method may invoke callbacks (and therefore the handle might be
		895	destroyed after it returns).
		896
561	=cut	897	=cut
562		898
563	sub on_drain {	899	sub on_drain {
564	my ($self, $cb) = @_;	900	my ($self, $cb) = @_;
565		901
…		…
569	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});	905	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
570	}	906	}
571		907
572	=item $handle->push_write ($data)	908	=item $handle->push_write ($data)
573		909
574	Queues the given scalar to be written. You can push as much data as you	910	Queues the given scalar to be written. You can push as much data as
575	want (only limited by the available memory), as C<AnyEvent::Handle>	911	you want (only limited by the available memory and C<wbuf_max>), as
576	buffers it independently of the kernel.	912	C<AnyEvent::Handle> buffers it independently of the kernel.
		913
		914	This method may invoke callbacks (and therefore the handle might be
		915	destroyed after it returns).
577		916
578	=cut	917	=cut
579		918
580	sub _drain_wbuf {	919	sub _drain_wbuf {
581	my ($self) = @_;	920	my ($self) = @_;
…		…
588	my $len = syswrite $self->{fh}, $self->{wbuf};	927	my $len = syswrite $self->{fh}, $self->{wbuf};
589		928
590	if (defined $len) {	929	if (defined $len) {
591	substr $self->{wbuf}, 0, $len, "";	930	substr $self->{wbuf}, 0, $len, "";
592		931
593	$self->{_activity} = AnyEvent->now;	932	$self->{_activity} = $self->{_wactivity} = AE::now;
594		933
595	$self->{on_drain}($self)	934	$self->{on_drain}($self)
596	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})	935	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
597	&& $self->{on_drain};	936	&& $self->{on_drain};
598		937
…		…
604		943
605	# try to write data immediately	944	# try to write data immediately
606	$cb->() unless $self->{autocork};	945	$cb->() unless $self->{autocork};
607		946
608	# if still data left in wbuf, we need to poll	947	# if still data left in wbuf, we need to poll
609	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	948	$self->{_ww} = AE::io $self->{fh}, 1, $cb
610	if length $self->{wbuf};	949	if length $self->{wbuf};
		950
		951	if (
		952	defined $self->{wbuf_max}
		953	&& $self->{wbuf_max} < length $self->{wbuf}
		954	) {
		955	$self->_error (Errno::ENOSPC, 1), return;
		956	}
611	};	957	};
612	}	958	}
613		959
614	our %WH;	960	our %WH;
615		961
		962	# deprecated
616	sub register_write_type($$) {	963	sub register_write_type($$) {
617	$WH{$_[0]} = $_[1];	964	$WH{$_[0]} = $_[1];
618	}	965	}
619		966
620	sub push_write {	967	sub push_write {
621	my $self = shift;	968	my $self = shift;
622		969
623	if (@_ > 1) {	970	if (@_ > 1) {
624	my $type = shift;	971	my $type = shift;
625		972
		973	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
626	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	974	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
627	->($self, @_);	975	->($self, @_);
628	}	976	}
629		977
		978	# we downgrade here to avoid hard-to-track-down bugs,
		979	# and diagnose the problem earlier and better.
		980
630	if ($self->{tls}) {	981	if ($self->{tls}) {
631	$self->{_tls_wbuf} .= $_[0];	982	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
632		983	&_dotls ($self) if $self->{fh};
633	&_dotls ($self);
634	} else {	984	} else {
635	$self->{wbuf} .= $_[0];	985	utf8::downgrade $self->{wbuf} .= $_[0];
636	$self->_drain_wbuf;	986	$self->_drain_wbuf if $self->{fh};
637	}	987	}
638	}	988	}
639		989
640	=item $handle->push_write (type => @args)	990	=item $handle->push_write (type => @args)
641		991
642	Instead of formatting your data yourself, you can also let this module do	992	Instead of formatting your data yourself, you can also let this module
643	the job by specifying a type and type-specific arguments.	993	do the job by specifying a type and type-specific arguments. You
		994	can also specify the (fully qualified) name of a package, in which
		995	case AnyEvent tries to load the package and then expects to find the
		996	C<anyevent_write_type> function inside (see "custom write types", below).
644		997
645	Predefined types are (if you have ideas for additional types, feel free to	998	Predefined types are (if you have ideas for additional types, feel free to
646	drop by and tell us):	999	drop by and tell us):
647		1000
648	=over 4	1001	=over 4
…		…
705	Other languages could read single lines terminated by a newline and pass	1058	Other languages could read single lines terminated by a newline and pass
706	this line into their JSON decoder of choice.	1059	this line into their JSON decoder of choice.
707		1060
708	=cut	1061	=cut
709		1062
		1063	sub json_coder() {
		1064	eval { require JSON::XS; JSON::XS->new->utf8 }
		1065	|| do { require JSON; JSON->new->utf8 }
		1066	}
		1067
710	register_write_type json => sub {	1068	register_write_type json => sub {
711	my ($self, $ref) = @_;	1069	my ($self, $ref) = @_;
712		1070
713	require JSON;	1071	my $json = $self->{json} ||= json_coder;
714		1072
715	$self->{json} ? $self->{json}->encode ($ref)	1073	$json->encode ($ref)
716	: JSON::encode_json ($ref)
717	};	1074	};
718		1075
719	=item storable => $reference	1076	=item storable => $reference
720		1077
721	Freezes the given reference using L<Storable> and writes it to the	1078	Freezes the given reference using L<Storable> and writes it to the
…		…
724	=cut	1081	=cut
725		1082
726	register_write_type storable => sub {	1083	register_write_type storable => sub {
727	my ($self, $ref) = @_;	1084	my ($self, $ref) = @_;
728		1085
729	require Storable;	1086	require Storable unless $Storable::VERSION;
730		1087
731	pack "w/a*", Storable::nfreeze ($ref)	1088	pack "w/a*", Storable::nfreeze ($ref)
732	};	1089	};
733		1090
734	=back	1091	=back
…		…
739	before it was actually written. One way to do that is to replace your	1096	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	1097	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	1098	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
742	replaces the C<on_drain> callback with:	1099	replaces the C<on_drain> callback with:
743		1100
744	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown	1101	sub { shutdown $_[0]{fh}, 1 }
745		1102
746	This simply shuts down the write side and signals an EOF condition to the	1103	This simply shuts down the write side and signals an EOF condition to the
747	the peer.	1104	the peer.
748		1105
749	You can rely on the normal read queue and C<on_eof> handling	1106	You can rely on the normal read queue and C<on_eof> handling
750	afterwards. This is the cleanest way to close a connection.	1107	afterwards. This is the cleanest way to close a connection.
751		1108
		1109	This method may invoke callbacks (and therefore the handle might be
		1110	destroyed after it returns).
		1111
752	=cut	1112	=cut
753		1113
754	sub push_shutdown {	1114	sub push_shutdown {
755	my ($self) = @_;	1115	my ($self) = @_;
756		1116
757	delete $self->{low_water_mark};	1117	delete $self->{low_water_mark};
758	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });	1118	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
759	}	1119	}
760		1120
761	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	1121	=item custom write types - Package::anyevent_write_type $handle, @args
762		1122
763	This function (not method) lets you add your own types to C<push_write>.	1123	Instead of one of the predefined types, you can also specify the name of
		1124	a package. AnyEvent will try to load the package and then expects to find
		1125	a function named C<anyevent_write_type> inside. If it isn't found, it
		1126	progressively tries to load the parent package until it either finds the
		1127	function (good) or runs out of packages (bad).
		1128
764	Whenever the given C<type> is used, C<push_write> will invoke the code	1129	Whenever the given C<type> is used, C<push_write> will the function with
765	reference with the handle object and the remaining arguments.	1130	the handle object and the remaining arguments.
766		1131
767	The code reference is supposed to return a single octet string that will	1132	The function is supposed to return a single octet string that will be
768	be appended to the write buffer.	1133	appended to the write buffer, so you can mentally treat this function as a
		1134	"arguments to on-the-wire-format" converter.
769		1135
770	Note that this is a function, and all types registered this way will be	1136	Example: implement a custom write type C<join> that joins the remaining
771	global, so try to use unique names.	1137	arguments using the first one.
		1138
		1139	$handle->push_write (My::Type => " ", 1,2,3);
		1140
		1141	# uses the following package, which can be defined in the "My::Type" or in
		1142	# the "My" modules to be auto-loaded, or just about anywhere when the
		1143	# My::Type::anyevent_write_type is defined before invoking it.
		1144
		1145	package My::Type;
		1146
		1147	sub anyevent_write_type {
		1148	my ($handle, $delim, @args) = @_;
		1149
		1150	join $delim, @args
		1151	}
772		1152
773	=cut	1153	=cut
774		1154
775	#############################################################################	1155	#############################################################################
776		1156
…		…
785	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1165	ways, the "simple" way, using only C<on_read> and the "complex" way, using
786	a queue.	1166	a queue.
787		1167
788	In the simple case, you just install an C<on_read> callback and whenever	1168	In the simple case, you just install an C<on_read> callback and whenever
789	new data arrives, it will be called. You can then remove some data (if	1169	new data arrives, it will be called. You can then remove some data (if
790	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna	1170	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
791	leave the data there if you want to accumulate more (e.g. when only a	1171	leave the data there if you want to accumulate more (e.g. when only a
792	partial message has been received so far).	1172	partial message has been received so far), or change the read queue with
		1173	e.g. C<push_read>.
793		1174
794	In the more complex case, you want to queue multiple callbacks. In this	1175	In the more complex case, you want to queue multiple callbacks. In this
795	case, AnyEvent::Handle will call the first queued callback each time new	1176	case, AnyEvent::Handle will call the first queued callback each time new
796	data arrives (also the first time it is queued) and removes it when it has	1177	data arrives (also the first time it is queued) and remove it when it has
797	done its job (see C<push_read>, below).	1178	done its job (see C<push_read>, below).
798		1179
799	This way you can, for example, push three line-reads, followed by reading	1180	This way you can, for example, push three line-reads, followed by reading
800	a chunk of data, and AnyEvent::Handle will execute them in order.	1181	a chunk of data, and AnyEvent::Handle will execute them in order.
801		1182
…		…
858	=cut	1239	=cut
859		1240
860	sub _drain_rbuf {	1241	sub _drain_rbuf {
861	my ($self) = @_;	1242	my ($self) = @_;
862		1243
		1244	# avoid recursion
		1245	return if $self->{_skip_drain_rbuf};
863	local $self->{_in_drain} = 1;	1246	local $self->{_skip_drain_rbuf} = 1;
864
865	if (
866	defined $self->{rbuf_max}
867	&& $self->{rbuf_max} < length $self->{rbuf}
868	) {
869	$self->_error (&Errno::ENOSPC, 1), return;
870	}
871		1247
872	while () {	1248	while () {
873	# we need to use a separate tls read buffer, as we must not receive data while	1249	# 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.	1250	# we are draining the buffer, and this can only happen with TLS.
875	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};	1251	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1252	if exists $self->{_tls_rbuf};
876		1253
877	my $len = length $self->{rbuf};	1254	my $len = length $self->{rbuf};
878		1255
879	if (my $cb = shift @{ $self->{_queue} }) {	1256	if (my $cb = shift @{ $self->{_queue} }) {
880	unless ($cb->($self)) {	1257	unless ($cb->($self)) {
881	if ($self->{_eof}) {	1258	# no progress can be made
882	# no progress can be made (not enough data and no data forthcoming)	1259	# (not enough data and no data forthcoming)
883	$self->_error (&Errno::EPIPE, 1), return;	1260	$self->_error (Errno::EPIPE, 1), return
884	}	1261	if $self->{_eof};
885		1262
886	unshift @{ $self->{_queue} }, $cb;	1263	unshift @{ $self->{_queue} }, $cb;
887	last;	1264	last;
888	}	1265	}
889	} elsif ($self->{on_read}) {	1266	} elsif ($self->{on_read}) {
…		…
896	&& !@{ $self->{_queue} } # and the queue is still empty	1273	&& !@{ $self->{_queue} } # and the queue is still empty
897	&& $self->{on_read} # but we still have on_read	1274	&& $self->{on_read} # but we still have on_read
898	) {	1275	) {
899	# no further data will arrive	1276	# no further data will arrive
900	# so no progress can be made	1277	# so no progress can be made
901	$self->_error (&Errno::EPIPE, 1), return	1278	$self->_error (Errno::EPIPE, 1), return
902	if $self->{_eof};	1279	if $self->{_eof};
903		1280
904	last; # more data might arrive	1281	last; # more data might arrive
905	}	1282	}
906	} else {	1283	} else {
…		…
909	last;	1286	last;
910	}	1287	}
911	}	1288	}
912		1289
913	if ($self->{_eof}) {	1290	if ($self->{_eof}) {
914	if ($self->{on_eof}) {	1291	$self->{on_eof}
915	$self->{on_eof}($self)	1292	? $self->{on_eof}($self)
916	} else {
917	$self->_error (0, 1, "Unexpected end-of-file");	1293	: $self->_error (0, 1, "Unexpected end-of-file");
918	}	1294
		1295	return;
		1296	}
		1297
		1298	if (
		1299	defined $self->{rbuf_max}
		1300	&& $self->{rbuf_max} < length $self->{rbuf}
		1301	) {
		1302	$self->_error (Errno::ENOSPC, 1), return;
919	}	1303	}
920		1304
921	# may need to restart read watcher	1305	# may need to restart read watcher
922	unless ($self->{_rw}) {	1306	unless ($self->{_rw}) {
923	$self->start_read	1307	$self->start_read
…		…
929		1313
930	This replaces the currently set C<on_read> callback, or clears it (when	1314	This replaces the currently set C<on_read> callback, or clears it (when
931	the new callback is C<undef>). See the description of C<on_read> in the	1315	the new callback is C<undef>). See the description of C<on_read> in the
932	constructor.	1316	constructor.
933		1317
		1318	This method may invoke callbacks (and therefore the handle might be
		1319	destroyed after it returns).
		1320
934	=cut	1321	=cut
935		1322
936	sub on_read {	1323	sub on_read {
937	my ($self, $cb) = @_;	1324	my ($self, $cb) = @_;
938		1325
939	$self->{on_read} = $cb;	1326	$self->{on_read} = $cb;
940	$self->_drain_rbuf if $cb && !$self->{_in_drain};	1327	$self->_drain_rbuf if $cb;
941	}	1328	}
942		1329
943	=item $handle->rbuf	1330	=item $handle->rbuf
944		1331
945	Returns the read buffer (as a modifiable lvalue).	1332	Returns the read buffer (as a modifiable lvalue). You can also access the
		1333	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1334	much faster, and no less clean).
946		1335
947	You can access the read buffer directly as the C<< ->{rbuf} >>	1336	The only operation allowed on the read buffer (apart from looking at it)
948	member, if you want. However, the only operation allowed on the	1337	is removing data from its beginning. Otherwise modifying or appending to
949	read buffer (apart from looking at it) is removing data from its	1338	it is not allowed and will lead to hard-to-track-down bugs.
950	beginning. Otherwise modifying or appending to it is not allowed and will
951	lead to hard-to-track-down bugs.
952		1339
953	NOTE: The read buffer should only be used or modified if the C<on_read>,	1340	NOTE: The read buffer should only be used or modified in the C<on_read>
954	C<push_read> or C<unshift_read> methods are used. The other read methods	1341	callback or when C<push_read> or C<unshift_read> are used with a single
955	automatically manage the read buffer.	1342	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1343	will manage the read buffer on their own.
956		1344
957	=cut	1345	=cut
958		1346
959	sub rbuf : lvalue {	1347	sub rbuf : lvalue {
960	$_[0]{rbuf}	1348	$_[0]{rbuf}
…		…
977		1365
978	If enough data was available, then the callback must remove all data it is	1366	If enough data was available, then the callback must remove all data it is
979	interested in (which can be none at all) and return a true value. After returning	1367	interested in (which can be none at all) and return a true value. After returning
980	true, it will be removed from the queue.	1368	true, it will be removed from the queue.
981		1369
		1370	These methods may invoke callbacks (and therefore the handle might be
		1371	destroyed after it returns).
		1372
982	=cut	1373	=cut
983		1374
984	our %RH;	1375	our %RH;
985		1376
986	sub register_read_type($$) {	1377	sub register_read_type($$) {
…		…
992	my $cb = pop;	1383	my $cb = pop;
993		1384
994	if (@_) {	1385	if (@_) {
995	my $type = shift;	1386	my $type = shift;
996		1387
		1388	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
997	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1389	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
998	->($self, $cb, @_);	1390	->($self, $cb, @_);
999	}	1391	}
1000		1392
1001	push @{ $self->{_queue} }, $cb;	1393	push @{ $self->{_queue} }, $cb;
1002	$self->_drain_rbuf unless $self->{_in_drain};	1394	$self->_drain_rbuf;
1003	}	1395	}
1004		1396
1005	sub unshift_read {	1397	sub unshift_read {
1006	my $self = shift;	1398	my $self = shift;
1007	my $cb = pop;	1399	my $cb = pop;
1008		1400
1009	if (@_) {	1401	if (@_) {
1010	my $type = shift;	1402	my $type = shift;
1011		1403
		1404	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1012	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1405	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1013	->($self, $cb, @_);	1406	->($self, $cb, @_);
1014	}	1407	}
1015		1408
1016
1017	unshift @{ $self->{_queue} }, $cb;	1409	unshift @{ $self->{_queue} }, $cb;
1018	$self->_drain_rbuf unless $self->{_in_drain};	1410	$self->_drain_rbuf;
1019	}	1411	}
1020		1412
1021	=item $handle->push_read (type => @args, $cb)	1413	=item $handle->push_read (type => @args, $cb)
1022		1414
1023	=item $handle->unshift_read (type => @args, $cb)	1415	=item $handle->unshift_read (type => @args, $cb)
1024		1416
1025	Instead of providing a callback that parses the data itself you can chose	1417	Instead of providing a callback that parses the data itself you can chose
1026	between a number of predefined parsing formats, for chunks of data, lines	1418	between a number of predefined parsing formats, for chunks of data, lines
1027	etc.	1419	etc. You can also specify the (fully qualified) name of a package, in
		1420	which case AnyEvent tries to load the package and then expects to find the
		1421	C<anyevent_read_type> function inside (see "custom read types", below).
1028		1422
1029	Predefined types are (if you have ideas for additional types, feel free to	1423	Predefined types are (if you have ideas for additional types, feel free to
1030	drop by and tell us):	1424	drop by and tell us):
1031		1425
1032	=over 4	1426	=over 4
…		…
1038	data.	1432	data.
1039		1433
1040	Example: read 2 bytes.	1434	Example: read 2 bytes.
1041		1435
1042	$handle->push_read (chunk => 2, sub {	1436	$handle->push_read (chunk => 2, sub {
1043	warn "yay ", unpack "H*", $_[1];	1437	say "yay " . unpack "H*", $_[1];
1044	});	1438	});
1045		1439
1046	=cut	1440	=cut
1047		1441
1048	register_read_type chunk => sub {	1442	register_read_type chunk => sub {
…		…
1124	the receive buffer when neither C<$accept> nor C<$reject> match,	1518	the receive buffer when neither C<$accept> nor C<$reject> match,
1125	and everything preceding and including the match will be accepted	1519	and everything preceding and including the match will be accepted
1126	unconditionally. This is useful to skip large amounts of data that you	1520	unconditionally. This is useful to skip large amounts of data that you
1127	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1521	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1128	have to start matching from the beginning. This is purely an optimisation	1522	have to start matching from the beginning. This is purely an optimisation
1129	and is usually worth only when you expect more than a few kilobytes.	1523	and is usually worth it only when you expect more than a few kilobytes.
1130		1524
1131	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1525	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1132	expect the header to be very large (it isn't in practise, but...), we use	1526	expect the header to be very large (it isn't in practice, but...), we use
1133	a skip regex to skip initial portions. The skip regex is tricky in that	1527	a skip regex to skip initial portions. The skip regex is tricky in that
1134	it only accepts something not ending in either \015 or \012, as these are	1528	it only accepts something not ending in either \015 or \012, as these are
1135	required for the accept regex.	1529	required for the accept regex.
1136		1530
1137	$handle->push_read (regex =>	1531	$handle->push_read (regex =>
…		…
1150		1544
1151	sub {	1545	sub {
1152	# accept	1546	# accept
1153	if ($$rbuf =~ $accept) {	1547	if ($$rbuf =~ $accept) {
1154	$data .= substr $$rbuf, 0, $+[0], "";	1548	$data .= substr $$rbuf, 0, $+[0], "";
1155	$cb->($self, $data);	1549	$cb->($_[0], $data);
1156	return 1;	1550	return 1;
1157	}	1551	}
1158		1552
1159	# reject	1553	# reject
1160	if ($reject && $$rbuf =~ $reject) {	1554	if ($reject && $$rbuf =~ $reject) {
1161	$self->_error (&Errno::EBADMSG);	1555	$_[0]->_error (Errno::EBADMSG);
1162	}	1556	}
1163		1557
1164	# skip	1558	# skip
1165	if ($skip && $$rbuf =~ $skip) {	1559	if ($skip && $$rbuf =~ $skip) {
1166	$data .= substr $$rbuf, 0, $+[0], "";	1560	$data .= substr $$rbuf, 0, $+[0], "";
…		…
1182	my ($self, $cb) = @_;	1576	my ($self, $cb) = @_;
1183		1577
1184	sub {	1578	sub {
1185	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1579	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1186	if ($_[0]{rbuf} =~ /[^0-9]/) {	1580	if ($_[0]{rbuf} =~ /[^0-9]/) {
1187	$self->_error (&Errno::EBADMSG);	1581	$_[0]->_error (Errno::EBADMSG);
1188	}	1582	}
1189	return;	1583	return;
1190	}	1584	}
1191		1585
1192	my $len = $1;	1586	my $len = $1;
1193		1587
1194	$self->unshift_read (chunk => $len, sub {	1588	$_[0]->unshift_read (chunk => $len, sub {
1195	my $string = $_[1];	1589	my $string = $_[1];
1196	$_[0]->unshift_read (chunk => 1, sub {	1590	$_[0]->unshift_read (chunk => 1, sub {
1197	if ($_[1] eq ",") {	1591	if ($_[1] eq ",") {
1198	$cb->($_[0], $string);	1592	$cb->($_[0], $string);
1199	} else {	1593	} else {
1200	$self->_error (&Errno::EBADMSG);	1594	$_[0]->_error (Errno::EBADMSG);
1201	}	1595	}
1202	});	1596	});
1203	});	1597	});
1204		1598
1205	1	1599	1
…		…
1272	=cut	1666	=cut
1273		1667
1274	register_read_type json => sub {	1668	register_read_type json => sub {
1275	my ($self, $cb) = @_;	1669	my ($self, $cb) = @_;
1276		1670
1277	my $json = $self->{json} ||=	1671	my $json = $self->{json} ||= json_coder;
1278	eval { require JSON::XS; JSON::XS->new->utf8 }
1279	|| do { require JSON; JSON->new->utf8 };
1280		1672
1281	my $data;	1673	my $data;
1282	my $rbuf = \$self->{rbuf};	1674	my $rbuf = \$self->{rbuf};
1283		1675
1284	sub {	1676	sub {
1285	my $ref = eval { $json->incr_parse ($self->{rbuf}) };	1677	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1286		1678
1287	if ($ref) {	1679	if ($ref) {
1288	$self->{rbuf} = $json->incr_text;	1680	$_[0]{rbuf} = $json->incr_text;
1289	$json->incr_text = "";	1681	$json->incr_text = "";
1290	$cb->($self, $ref);	1682	$cb->($_[0], $ref);
1291		1683
1292	1	1684	1
1293	} elsif ($@) {	1685	} elsif ($@) {
1294	# error case	1686	# error case
1295	$json->incr_skip;	1687	$json->incr_skip;
1296		1688
1297	$self->{rbuf} = $json->incr_text;	1689	$_[0]{rbuf} = $json->incr_text;
1298	$json->incr_text = "";	1690	$json->incr_text = "";
1299		1691
1300	$self->_error (&Errno::EBADMSG);	1692	$_[0]->_error (Errno::EBADMSG);
1301		1693
1302	()	1694	()
1303	} else {	1695	} else {
1304	$self->{rbuf} = "";	1696	$_[0]{rbuf} = "";
1305		1697
1306	()	1698	()
1307	}	1699	}
1308	}	1700	}
1309	};	1701	};
…		…
1319	=cut	1711	=cut
1320		1712
1321	register_read_type storable => sub {	1713	register_read_type storable => sub {
1322	my ($self, $cb) = @_;	1714	my ($self, $cb) = @_;
1323		1715
1324	require Storable;	1716	require Storable unless $Storable::VERSION;
1325		1717
1326	sub {	1718	sub {
1327	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method	1719	# 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} })	1720	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1329	or return;	1721	or return;
…		…
1342	# read remaining chunk	1734	# read remaining chunk
1343	$_[0]->unshift_read (chunk => $len, sub {	1735	$_[0]->unshift_read (chunk => $len, sub {
1344	if (my $ref = eval { Storable::thaw ($_[1]) }) {	1736	if (my $ref = eval { Storable::thaw ($_[1]) }) {
1345	$cb->($_[0], $ref);	1737	$cb->($_[0], $ref);
1346	} else {	1738	} else {
1347	$self->_error (&Errno::EBADMSG);	1739	$_[0]->_error (Errno::EBADMSG);
1348	}	1740	}
1349	});	1741	});
1350	}	1742	}
1351		1743
1352	1	1744	1
1353	}	1745	}
1354	};	1746	};
1355		1747
1356	=back	1748	=back
1357		1749
1358	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)	1750	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1359		1751
1360	This function (not method) lets you add your own types to C<push_read>.	1752	Instead of one of the predefined types, you can also specify the name
		1753	of a package. AnyEvent will try to load the package and then expects to
		1754	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1755	progressively tries to load the parent package until it either finds the
		1756	function (good) or runs out of packages (bad).
1361		1757
1362	Whenever the given C<type> is used, C<push_read> will invoke the code	1758	Whenever this type is used, C<push_read> will invoke the function with the
1363	reference with the handle object, the callback and the remaining	1759	handle object, the original callback and the remaining arguments.
1364	arguments.
1365		1760
1366	The code reference is supposed to return a callback (usually a closure)	1761	The function is supposed to return a callback (usually a closure) that
1367	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1762	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1763	mentally treat the function as a "configurable read type to read callback"
		1764	converter.
1368		1765
1369	It should invoke the passed callback when it is done reading (remember to	1766	It should invoke the original callback when it is done reading (remember
1370	pass C<$handle> as first argument as all other callbacks do that).	1767	to pass C<$handle> as first argument as all other callbacks do that,
		1768	although there is no strict requirement on this).
1371		1769
1372	Note that this is a function, and all types registered this way will be
1373	global, so try to use unique names.
1374
1375	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1770	For examples, see the source of this module (F<perldoc -m
1376	search for C<register_read_type>)).	1771	AnyEvent::Handle>, search for C<register_read_type>)).
1377		1772
1378	=item $handle->stop_read	1773	=item $handle->stop_read
1379		1774
1380	=item $handle->start_read	1775	=item $handle->start_read
1381		1776
…		…
1387	Note that AnyEvent::Handle will automatically C<start_read> for you when	1782	Note that AnyEvent::Handle will automatically C<start_read> for you when
1388	you change the C<on_read> callback or push/unshift a read callback, and it	1783	you change the C<on_read> callback or push/unshift a read callback, and it
1389	will automatically C<stop_read> for you when neither C<on_read> is set nor	1784	will automatically C<stop_read> for you when neither C<on_read> is set nor
1390	there are any read requests in the queue.	1785	there are any read requests in the queue.
1391		1786
1392	These methods will have no effect when in TLS mode (as TLS doesn't support	1787	In older versions of this module (<= 5.3), these methods had no effect,
1393	half-duplex connections).	1788	as TLS does not support half-duplex connections. In current versions they
		1789	work as expected, as this behaviour is required to avoid certain resource
		1790	attacks, where the program would be forced to read (and buffer) arbitrary
		1791	amounts of data before being able to send some data. The drawback is that
		1792	some readings of the the SSL/TLS specifications basically require this
		1793	attack to be working, as SSL/TLS implementations might stall sending data
		1794	during a rehandshake.
		1795
		1796	As a guideline, during the initial handshake, you should not stop reading,
		1797	and as a client, it might cause problems, depending on your applciation.
1394		1798
1395	=cut	1799	=cut
1396		1800
1397	sub stop_read {	1801	sub stop_read {
1398	my ($self) = @_;	1802	my ($self) = @_;
1399		1803
1400	delete $self->{_rw} unless $self->{tls};	1804	delete $self->{_rw};
1401	}	1805	}
1402		1806
1403	sub start_read {	1807	sub start_read {
1404	my ($self) = @_;	1808	my ($self) = @_;
1405		1809
1406	unless ($self->{_rw} || $self->{_eof}) {	1810	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1407	Scalar::Util::weaken $self;	1811	Scalar::Util::weaken $self;
1408		1812
1409	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1813	$self->{_rw} = AE::io $self->{fh}, 0, sub {
1410	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});	1814	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1411	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1815	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1412		1816
1413	if ($len > 0) {	1817	if ($len > 0) {
1414	$self->{_activity} = AnyEvent->now;	1818	$self->{_activity} = $self->{_ractivity} = AE::now;
1415		1819
1416	if ($self->{tls}) {	1820	if ($self->{tls}) {
1417	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);	1821	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1418		1822
1419	&_dotls ($self);	1823	&_dotls ($self);
1420	} else {	1824	} else {
1421	$self->_drain_rbuf unless $self->{_in_drain};	1825	$self->_drain_rbuf;
		1826	}
		1827
		1828	if ($len == $self->{read_size}) {
		1829	$self->{read_size} *= 2;
		1830	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1831	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1422	}	1832	}
1423		1833
1424	} elsif (defined $len) {	1834	} elsif (defined $len) {
1425	delete $self->{_rw};	1835	delete $self->{_rw};
1426	$self->{_eof} = 1;	1836	$self->{_eof} = 1;
1427	$self->_drain_rbuf unless $self->{_in_drain};	1837	$self->_drain_rbuf;
1428		1838
1429	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1839	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1430	return $self->_error ($!, 1);	1840	return $self->_error ($!, 1);
1431	}	1841	}
1432	});	1842	};
1433	}	1843	}
1434	}	1844	}
1435		1845
1436	our $ERROR_SYSCALL;	1846	our $ERROR_SYSCALL;
1437	our $ERROR_WANT_READ;	1847	our $ERROR_WANT_READ;
…		…
1450	if ($self->{_on_starttls}) {	1860	if ($self->{_on_starttls}) {
1451	(delete $self->{_on_starttls})->($self, undef, $err);	1861	(delete $self->{_on_starttls})->($self, undef, $err);
1452	&_freetls;	1862	&_freetls;
1453	} else {	1863	} else {
1454	&_freetls;	1864	&_freetls;
1455	$self->_error (&Errno::EPROTO, 1, $err);	1865	$self->_error (Errno::EPROTO, 1, $err);
1456	}	1866	}
1457	}	1867	}
1458		1868
1459	# poll the write BIO and send the data if applicable	1869	# poll the write BIO and send the data if applicable
1460	# also decode read data if possible	1870	# also decode read data if possible
…		…
1492	$self->{_eof} = 1;	1902	$self->{_eof} = 1;
1493	}	1903	}
1494	}	1904	}
1495		1905
1496	$self->{_tls_rbuf} .= $tmp;	1906	$self->{_tls_rbuf} .= $tmp;
1497	$self->_drain_rbuf unless $self->{_in_drain};	1907	$self->_drain_rbuf;
1498	$self->{tls} or return; # tls session might have gone away in callback	1908	$self->{tls} or return; # tls session might have gone away in callback
1499	}	1909	}
1500		1910
1501	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);	1911	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1502	return $self->_tls_error ($tmp)	1912	return $self->_tls_error ($tmp)
…		…
1504	&& ($tmp != $ERROR_SYSCALL || $!);	1914	&& ($tmp != $ERROR_SYSCALL || $!);
1505		1915
1506	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1916	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1507	$self->{wbuf} .= $tmp;	1917	$self->{wbuf} .= $tmp;
1508	$self->_drain_wbuf;	1918	$self->_drain_wbuf;
		1919	$self->{tls} or return; # tls session might have gone away in callback
1509	}	1920	}
1510		1921
1511	$self->{_on_starttls}	1922	$self->{_on_starttls}
1512	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()	1923	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1513	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");	1924	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
…		…
1516	=item $handle->starttls ($tls[, $tls_ctx])	1927	=item $handle->starttls ($tls[, $tls_ctx])
1517		1928
1518	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1929	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1519	object is created, you can also do that at a later time by calling	1930	object is created, you can also do that at a later time by calling
1520	C<starttls>.	1931	C<starttls>.
		1932
		1933	Starting TLS is currently an asynchronous operation - when you push some
		1934	write data and then call C<< ->starttls >> then TLS negotiation will start
		1935	immediately, after which the queued write data is then sent.
1521		1936
1522	The first argument is the same as the C<tls> constructor argument (either	1937	The first argument is the same as the C<tls> constructor argument (either
1523	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1938	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1524		1939
1525	The second argument is the optional C<AnyEvent::TLS> object that is used	1940	The second argument is the optional C<AnyEvent::TLS> object that is used
…		…
1530	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS	1945	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1531	context in C<< $handle->{tls_ctx} >> after this call and can be used or	1946	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1532	changed to your liking. Note that the handshake might have already started	1947	changed to your liking. Note that the handshake might have already started
1533	when this function returns.	1948	when this function returns.
1534		1949
1535	If it an error to start a TLS handshake more than once per	1950	Due to bugs in OpenSSL, it might or might not be possible to do multiple
1536	AnyEvent::Handle object (this is due to bugs in OpenSSL).	1951	handshakes on the same stream. It is best to not attempt to use the
		1952	stream after stopping TLS.
		1953
		1954	This method may invoke callbacks (and therefore the handle might be
		1955	destroyed after it returns).
1537		1956
1538	=cut	1957	=cut
1539		1958
1540	our %TLS_CACHE; #TODO not yet documented, should we?	1959	our %TLS_CACHE; #TODO not yet documented, should we?
1541		1960
1542	sub starttls {	1961	sub starttls {
1543	my ($self, $ssl, $ctx) = @_;	1962	my ($self, $tls, $ctx) = @_;
		1963
		1964	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1965	if $self->{tls};
		1966
		1967	$self->{tls} = $tls;
		1968	$self->{tls_ctx} = $ctx if @_ > 2;
		1969
		1970	return unless $self->{fh};
1544		1971
1545	require Net::SSLeay;	1972	require Net::SSLeay;
1546
1547	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1548	if $self->{tls};
1549		1973
1550	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();	1974	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1551	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();	1975	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1552		1976
		1977	$tls = delete $self->{tls};
1553	$ctx ||= $self->{tls_ctx};	1978	$ctx = $self->{tls_ctx};
		1979
		1980	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1554		1981
1555	if ("HASH" eq ref $ctx) {	1982	if ("HASH" eq ref $ctx) {
1556	require AnyEvent::TLS;	1983	require AnyEvent::TLS;
1557
1558	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
1559		1984
1560	if ($ctx->{cache}) {	1985	if ($ctx->{cache}) {
1561	my $key = $ctx+0;	1986	my $key = $ctx+0;
1562	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;	1987	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1563	} else {	1988	} else {
1564	$ctx = new AnyEvent::TLS %$ctx;	1989	$ctx = new AnyEvent::TLS %$ctx;
1565	}	1990	}
1566	}	1991	}
1567		1992
1568	$self->{tls_ctx} = $ctx || TLS_CTX ();	1993	$self->{tls_ctx} = $ctx || TLS_CTX ();
1569	$self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});	1994	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1570		1995
1571	# basically, this is deep magic (because SSL_read should have the same issues)	1996	# basically, this is deep magic (because SSL_read should have the same issues)
1572	# but the openssl maintainers basically said: "trust us, it just works".	1997	# but the openssl maintainers basically said: "trust us, it just works".
1573	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1998	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1574	# and mismaintained ssleay-module doesn't even offer them).	1999	# and mismaintained ssleay-module doesn't even offer them).
…		…
1581	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to	2006	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1582	# have identity issues in that area.	2007	# have identity issues in that area.
1583	# Net::SSLeay::CTX_set_mode ($ssl,	2008	# Net::SSLeay::CTX_set_mode ($ssl,
1584	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2009	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1585	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2010	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1586	Net::SSLeay::CTX_set_mode ($ssl, 1|2);	2011	Net::SSLeay::CTX_set_mode ($tls, 1|2);
1587		2012
1588	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2013	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1589	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2014	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1590		2015
		2016	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2017	$self->{rbuf} = "";
		2018
1591	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	2019	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1592		2020
1593	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }	2021	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1594	if $self->{on_starttls};	2022	if $self->{on_starttls};
1595		2023
1596	&_dotls; # need to trigger the initial handshake	2024	&_dotls; # need to trigger the initial handshake
…		…
1599		2027
1600	=item $handle->stoptls	2028	=item $handle->stoptls
1601		2029
1602	Shuts down the SSL connection - this makes a proper EOF handshake by	2030	Shuts down the SSL connection - this makes a proper EOF handshake by
1603	sending a close notify to the other side, but since OpenSSL doesn't	2031	sending a close notify to the other side, but since OpenSSL doesn't
1604	support non-blocking shut downs, it is not possible to re-use the stream	2032	support non-blocking shut downs, it is not guaranteed that you can re-use
1605	afterwards.	2033	the stream afterwards.
		2034
		2035	This method may invoke callbacks (and therefore the handle might be
		2036	destroyed after it returns).
1606		2037
1607	=cut	2038	=cut
1608		2039
1609	sub stoptls {	2040	sub stoptls {
1610	my ($self) = @_;	2041	my ($self) = @_;
1611		2042
1612	if ($self->{tls}) {	2043	if ($self->{tls} && $self->{fh}) {
1613	Net::SSLeay::shutdown ($self->{tls});	2044	Net::SSLeay::shutdown ($self->{tls});
1614		2045
1615	&_dotls;	2046	&_dotls;
1616		2047
1617	# # we don't give a shit. no, we do, but we can't. no...#d#	2048	# # we don't give a shit. no, we do, but we can't. no...#d#
…		…
1623	sub _freetls {	2054	sub _freetls {
1624	my ($self) = @_;	2055	my ($self) = @_;
1625		2056
1626	return unless $self->{tls};	2057	return unless $self->{tls};
1627		2058
1628	$self->{tls_ctx}->_put_session (delete $self->{tls});	2059	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2060	if $self->{tls} > 0;
1629		2061
1630	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};	2062	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1631	}	2063	}
1632		2064
		2065	=item $handle->resettls
		2066
		2067	This rarely-used method simply resets and TLS state on the handle, usually
		2068	causing data loss.
		2069
		2070	One case where it may be useful is when you want to skip over the data in
		2071	the stream but you are not interested in interpreting it, so data loss is
		2072	no concern.
		2073
		2074	=cut
		2075
		2076	*resettls = \&_freetls;
		2077
1633	sub DESTROY {	2078	sub DESTROY {
1634	my ($self) = @_;	2079	my ($self) = @_;
1635		2080
1636	&_freetls;	2081	&_freetls;
1637		2082
1638	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	2083	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1639		2084
1640	if ($linger && length $self->{wbuf}) {	2085	if ($linger && length $self->{wbuf} && $self->{fh}) {
1641	my $fh = delete $self->{fh};	2086	my $fh = delete $self->{fh};
1642	my $wbuf = delete $self->{wbuf};	2087	my $wbuf = delete $self->{wbuf};
1643		2088
1644	my @linger;	2089	my @linger;
1645		2090
1646	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {	2091	push @linger, AE::io $fh, 1, sub {
1647	my $len = syswrite $fh, $wbuf, length $wbuf;	2092	my $len = syswrite $fh, $wbuf, length $wbuf;
1648		2093
1649	if ($len > 0) {	2094	if ($len > 0) {
1650	substr $wbuf, 0, $len, "";	2095	substr $wbuf, 0, $len, "";
1651	} else {	2096	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1652	@linger = (); # end	2097	@linger = (); # end
1653	}	2098	}
1654	});	2099	};
1655	push @linger, AnyEvent->timer (after => $linger, cb => sub {	2100	push @linger, AE::timer $linger, 0, sub {
1656	@linger = ();	2101	@linger = ();
1657	});	2102	};
1658	}	2103	}
1659	}	2104	}
1660		2105
1661	=item $handle->destroy	2106	=item $handle->destroy
1662		2107
1663	Shuts down the handle object as much as possible - this call ensures that	2108	Shuts down the handle object as much as possible - this call ensures that
1664	no further callbacks will be invoked and as many resources as possible	2109	no further callbacks will be invoked and as many resources as possible
1665	will be freed. You must not call any methods on the object afterwards.	2110	will be freed. Any method you will call on the handle object after
		2111	destroying it in this way will be silently ignored (and it will return the
		2112	empty list).
1666		2113
1667	Normally, you can just "forget" any references to an AnyEvent::Handle	2114	Normally, you can just "forget" any references to an AnyEvent::Handle
1668	object and it will simply shut down. This works in fatal error and EOF	2115	object and it will simply shut down. This works in fatal error and EOF
1669	callbacks, as well as code outside. It does I<NOT> work in a read or write	2116	callbacks, as well as code outside. It does I<NOT> work in a read or write
1670	callback, so when you want to destroy the AnyEvent::Handle object from	2117	callback, so when you want to destroy the AnyEvent::Handle object from
…		…
1684	sub destroy {	2131	sub destroy {
1685	my ($self) = @_;	2132	my ($self) = @_;
1686		2133
1687	$self->DESTROY;	2134	$self->DESTROY;
1688	%$self = ();	2135	%$self = ();
		2136	bless $self, "AnyEvent::Handle::destroyed";
1689	}	2137	}
		2138
		2139	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2140	#nop
		2141	}
		2142
		2143	=item $handle->destroyed
		2144
		2145	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2146	->destroy >>, true otherwise.
		2147
		2148	Can be useful to decide whether the handle is still valid after some
		2149	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2150	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2151	can destroy the handle, so work can be avoided by checking sometimes:
		2152
		2153	$hdl->starttls ("accept");
		2154	return if $hdl->destroyed;
		2155	$hdl->push_write (...
		2156
		2157	Note that the call to C<push_write> will silently be ignored if the handle
		2158	has been destroyed, so often you can just ignore the possibility of the
		2159	handle being destroyed.
		2160
		2161	=cut
		2162
		2163	sub destroyed { 0 }
		2164	sub AnyEvent::Handle::destroyed::destroyed { 1 }
1690		2165
1691	=item AnyEvent::Handle::TLS_CTX	2166	=item AnyEvent::Handle::TLS_CTX
1692		2167
1693	This function creates and returns the AnyEvent::TLS object used by default	2168	This function creates and returns the AnyEvent::TLS object used by default
1694	for TLS mode.	2169	for TLS mode.
…		…
1722		2197
1723	It is only safe to "forget" the reference inside EOF or error callbacks,	2198	It is only safe to "forget" the reference inside EOF or error callbacks,
1724	from within all other callbacks, you need to explicitly call the C<<	2199	from within all other callbacks, you need to explicitly call the C<<
1725	->destroy >> method.	2200	->destroy >> method.
1726		2201
		2202	=item Why is my C<on_eof> callback never called?
		2203
		2204	Probably because your C<on_error> callback is being called instead: When
		2205	you have outstanding requests in your read queue, then an EOF is
		2206	considered an error as you clearly expected some data.
		2207
		2208	To avoid this, make sure you have an empty read queue whenever your handle
		2209	is supposed to be "idle" (i.e. connection closes are O.K.). You can set
		2210	an C<on_read> handler that simply pushes the first read requests in the
		2211	queue.
		2212
		2213	See also the next question, which explains this in a bit more detail.
		2214
		2215	=item How can I serve requests in a loop?
		2216
		2217	Most protocols consist of some setup phase (authentication for example)
		2218	followed by a request handling phase, where the server waits for requests
		2219	and handles them, in a loop.
		2220
		2221	There are two important variants: The first (traditional, better) variant
		2222	handles requests until the server gets some QUIT command, causing it to
		2223	close the connection first (highly desirable for a busy TCP server). A
		2224	client dropping the connection is an error, which means this variant can
		2225	detect an unexpected detection close.
		2226
		2227	To handle this case, always make sure you have a on-empty read queue, by
		2228	pushing the "read request start" handler on it:
		2229
		2230	# we assume a request starts with a single line
		2231	my @start_request; @start_request = (line => sub {
		2232	my ($hdl, $line) = @_;
		2233
		2234	... handle request
		2235
		2236	# push next request read, possibly from a nested callback
		2237	$hdl->push_read (@start_request);
		2238	});
		2239
		2240	# auth done, now go into request handling loop
		2241	# now push the first @start_request
		2242	$hdl->push_read (@start_request);
		2243
		2244	By always having an outstanding C<push_read>, the handle always expects
		2245	some data and raises the C<EPIPE> error when the connction is dropped
		2246	unexpectedly.
		2247
		2248	The second variant is a protocol where the client can drop the connection
		2249	at any time. For TCP, this means that the server machine may run out of
		2250	sockets easier, and in general, it means you cannot distinguish a protocl
		2251	failure/client crash from a normal connection close. Nevertheless, these
		2252	kinds of protocols are common (and sometimes even the best solution to the
		2253	problem).
		2254
		2255	Having an outstanding read request at all times is possible if you ignore
		2256	C<EPIPE> errors, but this doesn't help with when the client drops the
		2257	connection during a request, which would still be an error.
		2258
		2259	A better solution is to push the initial request read in an C<on_read>
		2260	callback. This avoids an error, as when the server doesn't expect data
		2261	(i.e. is idly waiting for the next request, an EOF will not raise an
		2262	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2263	and simpler:
		2264
		2265	# auth done, now go into request handling loop
		2266	$hdl->on_read (sub {
		2267	my ($hdl) = @_;
		2268
		2269	# called each time we receive data but the read queue is empty
		2270	# simply start read the request
		2271
		2272	$hdl->push_read (line => sub {
		2273	my ($hdl, $line) = @_;
		2274
		2275	... handle request
		2276
		2277	# do nothing special when the request has been handled, just
		2278	# let the request queue go empty.
		2279	});
		2280	});
		2281
1727	=item I get different callback invocations in TLS mode/Why can't I pause	2282	=item I get different callback invocations in TLS mode/Why can't I pause
1728	reading?	2283	reading?
1729		2284
1730	Unlike, say, TCP, TLS connections do not consist of two independent	2285	Unlike, say, TCP, TLS connections do not consist of two independent
1731	communication channels, one for each direction. Or put differently. The	2286	communication channels, one for each direction. Or put differently, the
1732	read and write directions are not independent of each other: you cannot	2287	read and write directions are not independent of each other: you cannot
1733	write data unless you are also prepared to read, and vice versa.	2288	write data unless you are also prepared to read, and vice versa.
1734		2289
1735	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>	2290	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1736	callback invocations when you are not expecting any read data - the reason	2291	callback invocations when you are not expecting any read data - the reason
1737	is that AnyEvent::Handle always reads in TLS mode.	2292	is that AnyEvent::Handle always reads in TLS mode.
1738		2293
1739	During the connection, you have to make sure that you always have a	2294	During the connection, you have to make sure that you always have a
1740	non-empty read-queue, or an C<on_read> watcher. At the end of the	2295	non-empty read-queue, or an C<on_read> watcher. At the end of the
…		…
1752	$handle->on_eof (undef);	2307	$handle->on_eof (undef);
1753	$handle->on_error (sub {	2308	$handle->on_error (sub {
1754	my $data = delete $_[0]{rbuf};	2309	my $data = delete $_[0]{rbuf};
1755	});	2310	});
1756		2311
		2312	Note that this example removes the C<rbuf> member from the handle object,
		2313	which is not normally allowed by the API. It is expressly permitted in
		2314	this case only, as the handle object needs to be destroyed afterwards.
		2315
1757	The reason to use C<on_error> is that TCP connections, due to latencies	2316	The reason to use C<on_error> is that TCP connections, due to latencies
1758	and packets loss, might get closed quite violently with an error, when in	2317	and packets loss, might get closed quite violently with an error, when in
1759	fact, all data has been received.	2318	fact all data has been received.
1760		2319
1761	It is usually better to use acknowledgements when transferring data,	2320	It is usually better to use acknowledgements when transferring data,
1762	to make sure the other side hasn't just died and you got the data	2321	to make sure the other side hasn't just died and you got the data
1763	intact. This is also one reason why so many internet protocols have an	2322	intact. This is also one reason why so many internet protocols have an
1764	explicit QUIT command.	2323	explicit QUIT command.
…		…
1771	C<low_water_mark> this will be called precisely when all data has been	2330	C<low_water_mark> this will be called precisely when all data has been
1772	written to the socket:	2331	written to the socket:
1773		2332
1774	$handle->push_write (...);	2333	$handle->push_write (...);
1775	$handle->on_drain (sub {	2334	$handle->on_drain (sub {
1776	warn "all data submitted to the kernel\n";	2335	AE::log debug => "all data submitted to the kernel\n";
1777	undef $handle;	2336	undef $handle;
1778	});	2337	});
1779		2338
1780	If you just want to queue some data and then signal EOF to the other side,	2339	If you just want to queue some data and then signal EOF to the other side,
1781	consider using C<< ->push_shutdown >> instead.	2340	consider using C<< ->push_shutdown >> instead.
1782		2341
1783	=item I want to contact a TLS/SSL server, I don't care about security.	2342	=item I want to contact a TLS/SSL server, I don't care about security.
1784		2343
1785	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,	2344	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1786	simply connect to it and then create the AnyEvent::Handle with the C<tls>	2345	connect to it and then create the AnyEvent::Handle with the C<tls>
1787	parameter:	2346	parameter:
1788		2347
1789	tcp_connect $host, $port, sub {	2348	tcp_connect $host, $port, sub {
1790	my ($fh) = @_;	2349	my ($fh) = @_;
1791		2350
…		…
1891		2450
1892	=item * all members not documented here and not prefixed with an underscore	2451	=item * all members not documented here and not prefixed with an underscore
1893	are free to use in subclasses.	2452	are free to use in subclasses.
1894		2453
1895	Of course, new versions of AnyEvent::Handle may introduce more "public"	2454	Of course, new versions of AnyEvent::Handle may introduce more "public"
1896	member variables, but thats just life, at least it is documented.	2455	member variables, but that's just life. At least it is documented.
1897		2456
1898	=back	2457	=back
1899		2458
1900	=head1 AUTHOR	2459	=head1 AUTHOR
1901		2460

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