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Revision 1.216 by root, Sun Jan 23 11:15:09 2011 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict;
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 = 4.14;
20		4
21	=head1 SYNOPSIS	5	=head1 SYNOPSIS
22		6
23	use AnyEvent;	7	use AnyEvent;
24	use AnyEvent::Handle;	8	use AnyEvent::Handle;
25		9
26	my $cv = AnyEvent->condvar;	10	my $cv = AnyEvent->condvar;
27		11
28	my $handle =	12	my $hdl; $hdl = new AnyEvent::Handle
29	AnyEvent::Handle->new (
30	fh => \*STDIN,	13	fh => \*STDIN,
31	on_eof => sub {	14	on_error => sub {
32	$cv->broadcast;	15	my ($hdl, $fatal, $msg) = @_;
33	},	16	warn "got error $msg\n";
		17	$hdl->destroy;
		18	$cv->send;
34	);	19	};
35		20
36	# send some request line	21	# send some request line
37	$handle->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
38		23
39	# read the response line	24	# read the response line
40	$handle->push_read (line => sub {	25	$hdl->push_read (line => sub {
41	my ($handle, $line) = @_;	26	my ($hdl, $line) = @_;
42	warn "read line <$line>\n";	27	warn "got line <$line>\n";
43	$cv->send;	28	$cv->send;
44	});	29	});
45		30
46	$cv->recv;	31	$cv->recv;
47		32
48	=head1 DESCRIPTION	33	=head1 DESCRIPTION
49		34
50	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
51	filehandles. For utility functions for doing non-blocking connects and accepts	36	stream-based filehandles (sockets, pipes, and other stream things).
52	on sockets see L<AnyEvent::Util>.
53		37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
		40
54	In the following, when the documentation refers to of "bytes" then this	41	In the following, where the documentation refers to "bytes", it means
55	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
56	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.
57		47
58	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
59	argument.	49	argument.
60		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
61	=head1 METHODS	82	=head1 METHODS
62		83
63	=over 4	84	=over 4
64		85
65	=item B<new (%args)>	86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
66		87
67	The constructor supports these arguments (all as key => value pairs).	88	The constructor supports these arguments (all as C<< key => value >> pairs).
68		89
69	=over 4	90	=over 4
70		91
71	=item fh => $filehandle [MANDATORY]	92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
72		93
73	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
74
75	NOTE: The filehandle will be set to non-blocking (using	95	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		97	that mode.
77		98
		99	=item connect => [$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
78	=item on_eof => $cb->($handle)	116	=item on_prepare => $cb->($handle)
79		117
80	Set the callback to be called when an end-of-file condition is detcted,	118	This (rarely used) callback is called before a new connection is
81	i.e. in the case of a socket, when the other side has closed the	119	attempted, but after the file handle has been created (you can access that
82	connection cleanly.	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).
83		123
84	While not mandatory, it is highly recommended to set an eof callback,	124	The return value of this callback should be the connect timeout value in
85	otherwise you might end up with a closed socket while you are still	125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
86	waiting for data.	126	default timeout is to be used).
87		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
88	=item on_error => $cb->($handle, $fatal)	154	=item on_error => $cb->($handle, $fatal, $message)
89		155
90	This is the error callback, which is called when, well, some error	156	This is the error callback, which is called when, well, some error
91	occured, such as not being able to resolve the hostname, failure to	157	occured, such as not being able to resolve the hostname, failure to
92	connect or a read error.	158	connect, or a read error.
93		159
94	Some errors are fatal (which is indicated by C<$fatal> being true). On	160	Some errors are fatal (which is indicated by C<$fatal> being true). On
95	fatal errors the handle object will be shut down and will not be	161	fatal errors the handle object will be destroyed (by a call to C<< ->
		162	destroy >>) after invoking the error callback (which means you are free to
		163	examine the handle object). Examples of fatal errors are an EOF condition
		164	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		165	cases where the other side can close the connection at will, it is
		166	often easiest to not report C<EPIPE> errors in this callback.
		167
		168	AnyEvent::Handle tries to find an appropriate error code for you to check
		169	against, but in some cases (TLS errors), this does not work well. It is
		170	recommended to always output the C<$message> argument in human-readable
		171	error messages (it's usually the same as C<"$!">).
		172
96	usable. Non-fatal errors can be retried by simply returning, but it is	173	Non-fatal errors can be retried by returning, but it is recommended
97	recommended to simply ignore this parameter and instead abondon the handle	174	to simply ignore this parameter and instead abondon the handle object
98	object when this callback is invoked.	175	when this callback is invoked. Examples of non-fatal errors are timeouts
		176	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99		177
100	On callback entrance, the value of C<$!> contains the operating system	178	On entry to the callback, the value of C<$!> contains the operating
101	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).	179	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		180	C<EPROTO>).
102		181
103	While not mandatory, it is I<highly> recommended to set this callback, as	182	While not mandatory, it is I<highly> recommended to set this callback, as
104	you will not be notified of errors otherwise. The default simply calls	183	you will not be notified of errors otherwise. The default just calls
105	C<croak>.	184	C<croak>.
106		185
107	=item on_read => $cb->($handle)	186	=item on_read => $cb->($handle)
108		187
109	This sets the default read callback, which is called when data arrives	188	This sets the default read callback, which is called when data arrives
110	and no read request is in the queue (unlike read queue callbacks, this	189	and no read request is in the queue (unlike read queue callbacks, this
111	callback will only be called when at least one octet of data is in the	190	callback will only be called when at least one octet of data is in the
112	read buffer).	191	read buffer).
113		192
114	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	193	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
115	method or access the C<$handle->{rbuf}> member directly.	194	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		195	must not enlarge or modify the read buffer, you can only remove data at
		196	the beginning from it.
116		197
		198	You can also call C<< ->push_read (...) >> or any other function that
		199	modifies the read queue. Or do both. Or ...
		200
117	When an EOF condition is detected then AnyEvent::Handle will first try to	201	When an EOF condition is detected, AnyEvent::Handle will first try to
118	feed all the remaining data to the queued callbacks and C<on_read> before	202	feed all the remaining data to the queued callbacks and C<on_read> before
119	calling the C<on_eof> callback. If no progress can be made, then a fatal	203	calling the C<on_eof> callback. If no progress can be made, then a fatal
120	error will be raised (with C<$!> set to C<EPIPE>).	204	error will be raised (with C<$!> set to C<EPIPE>).
121		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
		211	=item on_eof => $cb->($handle)
		212
		213	Set the callback to be called when an end-of-file condition is detected,
		214	i.e. in the case of a socket, when the other side has closed the
		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).
		218
		219	For sockets, this just means that the other side has stopped sending data,
		220	you can still try to write data, and, in fact, one can return from the EOF
		221	callback and continue writing data, as only the read part has been shut
		222	down.
		223
		224	If an EOF condition has been detected but no C<on_eof> callback has been
		225	set, then a fatal error will be raised with C<$!> set to <0>.
		226
122	=item on_drain => $cb->($handle)	227	=item on_drain => $cb->($handle)
123		228
124	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
125	(or when the callback is set and the buffer is empty already).	230	(or immediately if the buffer is empty already).
126		231
127	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.
128		233
		234	This callback is useful when you don't want to put all of your write data
		235	into the queue at once, for example, when you want to write the contents
		236	of some file to the socket you might not want to read the whole file into
		237	memory and push it into the queue, but instead only read more data from
		238	the file when the write queue becomes empty.
		239
129	=item timeout => $fractional_seconds	240	=item timeout => $fractional_seconds
130		241
		242	=item rtimeout => $fractional_seconds
		243
		244	=item wtimeout => $fractional_seconds
		245
131	If non-zero, then this enables an "inactivity" timeout: whenever this many	246	If non-zero, then these enables an "inactivity" timeout: whenever this
132	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
133	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
134	missing, an 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).
135		251
		252	There are three variants of the timeouts that work independently
		253	of each other, for both read and write, just read, and just write:
		254	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		255	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		256	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		257
136	Note that timeout processing is also active when you currently do not have	258	Note that timeout processing is active even when you do not have
137	any outstanding read or write requests: If you plan to keep the connection	259	any outstanding read or write requests: If you plan to keep the connection
138	idle then you should disable the timout temporarily or ignore the timeout	260	idle then you should disable the timeout temporarily or ignore the timeout
139	in the C<on_timeout> callback.	261	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		262	restart the timeout.
140		263
141	Zero (the default) disables this timeout.	264	Zero (the default) disables this timeout.
142		265
143	=item on_timeout => $cb->($handle)	266	=item on_timeout => $cb->($handle)
144		267
…		…
148		271
149	=item rbuf_max => <bytes>	272	=item rbuf_max => <bytes>
150		273
151	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	274	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
152	when the read buffer ever (strictly) exceeds this size. This is useful to	275	when the read buffer ever (strictly) exceeds this size. This is useful to
153	avoid denial-of-service attacks.	276	avoid some forms of denial-of-service attacks.
154		277
155	For example, a server accepting connections from untrusted sources should	278	For example, a server accepting connections from untrusted sources should
156	be configured to accept only so-and-so much data that it cannot act on	279	be configured to accept only so-and-so much data that it cannot act on
157	(for example, when expecting a line, an attacker could send an unlimited	280	(for example, when expecting a line, an attacker could send an unlimited
158	amount of data without a callback ever being called as long as the line	281	amount of data without a callback ever being called as long as the line
159	isn't finished).	282	isn't finished).
160		283
		284	=item wbuf_max => <bytes>
		285
		286	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		287	when the write buffer ever (strictly) exceeds this size. This is useful to
		288	avoid some forms of denial-of-service attacks.
		289
		290	Although the units of this parameter is bytes, this is the I<raw> number
		291	of bytes not yet accepted by the kernel. This can make a difference when
		292	you e.g. use TLS, as TLS typically makes your write data larger (but it
		293	can also make it smaller due to compression).
		294
		295	As an example of when this limit is useful, take a chat server that sends
		296	chat messages to a client. If the client does not read those in a timely
		297	manner then the send buffer in the server would grow unbounded.
		298
		299	=item autocork => <boolean>
		300
		301	When disabled (the default), C<push_write> will try to immediately
		302	write the data to the handle if possible. This avoids having to register
		303	a write watcher and wait for the next event loop iteration, but can
		304	be inefficient if you write multiple small chunks (on the wire, this
		305	disadvantage is usually avoided by your kernel's nagle algorithm, see
		306	C<no_delay>, but this option can save costly syscalls).
		307
		308	When enabled, writes will always be queued till the next event loop
		309	iteration. This is efficient when you do many small writes per iteration,
		310	but less efficient when you do a single write only per iteration (or when
		311	the write buffer often is full). It also increases write latency.
		312
		313	=item no_delay => <boolean>
		314
		315	When doing small writes on sockets, your operating system kernel might
		316	wait a bit for more data before actually sending it out. This is called
		317	the Nagle algorithm, and usually it is beneficial.
		318
		319	In some situations you want as low a delay as possible, which can be
		320	accomplishd by setting this option to a true value.
		321
		322	The default is your operating system's default behaviour (most likely
		323	enabled). This option explicitly enables or disables it, if possible.
		324
		325	=item keepalive => <boolean>
		326
		327	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		328	normally, TCP connections have no time-out once established, so TCP
		329	connections, once established, can stay alive forever even when the other
		330	side has long gone. TCP keepalives are a cheap way to take down long-lived
		331	TCP connections when the other side becomes unreachable. While the default
		332	is OS-dependent, TCP keepalives usually kick in after around two hours,
		333	and, if the other side doesn't reply, take down the TCP connection some 10
		334	to 15 minutes later.
		335
		336	It is harmless to specify this option for file handles that do not support
		337	keepalives, and enabling it on connections that are potentially long-lived
		338	is usually a good idea.
		339
		340	=item oobinline => <boolean>
		341
		342	BSD majorly fucked up the implementation of TCP urgent data. The result
		343	is that almost no OS implements TCP according to the specs, and every OS
		344	implements it slightly differently.
		345
		346	If you want to handle TCP urgent data, then setting this flag (the default
		347	is enabled) gives you the most portable way of getting urgent data, by
		348	putting it into the stream.
		349
		350	Since BSD emulation of OOB data on top of TCP's urgent data can have
		351	security implications, AnyEvent::Handle sets this flag automatically
		352	unless explicitly specified. Note that setting this flag after
		353	establishing a connection I<may> be a bit too late (data loss could
		354	already have occured on BSD systems), but at least it will protect you
		355	from most attacks.
		356
161	=item read_size => <bytes>	357	=item read_size => <bytes>
162		358
163	The default read block size (the amount of bytes this module will try to read	359	The initial read block size, the number of bytes this module will try to
164	during each (loop iteration). Default: C<8192>.	360	read during each loop iteration. Each handle object will consume at least
		361	this amount of memory for the read buffer as well, so when handling many
		362	connections requirements). See also C<max_read_size>. Default: C<2048>.
		363
		364	=item max_read_size => <bytes>
		365
		366	The maximum read buffer size used by the dynamic adjustment
		367	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		368	one go it will double C<read_size> up to the maximum given by this
		369	option. Default: C<131072> or C<read_size>, whichever is higher.
165		370
166	=item low_water_mark => <bytes>	371	=item low_water_mark => <bytes>
167		372
168	Sets the amount of bytes (default: C<0>) that make up an "empty" write	373	Sets the number of bytes (default: C<0>) that make up an "empty" write
169	buffer: If the write reaches this size or gets even samller it is	374	buffer: If the buffer reaches this size or gets even samller it is
170	considered empty.	375	considered empty.
171		376
		377	Sometimes it can be beneficial (for performance reasons) to add data to
		378	the write buffer before it is fully drained, but this is a rare case, as
		379	the operating system kernel usually buffers data as well, so the default
		380	is good in almost all cases.
		381
		382	=item linger => <seconds>
		383
		384	If this is non-zero (default: C<3600>), the destructor of the
		385	AnyEvent::Handle object will check whether there is still outstanding
		386	write data and will install a watcher that will write this data to the
		387	socket. No errors will be reported (this mostly matches how the operating
		388	system treats outstanding data at socket close time).
		389
		390	This will not work for partial TLS data that could not be encoded
		391	yet. This data will be lost. Calling the C<stoptls> method in time might
		392	help.
		393
		394	=item peername => $string
		395
		396	A string used to identify the remote site - usually the DNS hostname
		397	(I<not> IDN!) used to create the connection, rarely the IP address.
		398
		399	Apart from being useful in error messages, this string is also used in TLS
		400	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		401	verification will be skipped when C<peername> is not specified or is
		402	C<undef>.
		403
172	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	404	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
173		405
174	When this parameter is given, it enables TLS (SSL) mode, that means it	406	When this parameter is given, it enables TLS (SSL) mode, that means
175	will start making tls handshake and will transparently encrypt/decrypt	407	AnyEvent will start a TLS handshake as soon as the connection has been
176	data.	408	established and will transparently encrypt/decrypt data afterwards.
		409
		410	All TLS protocol errors will be signalled as C<EPROTO>, with an
		411	appropriate error message.
177		412
178	TLS mode requires Net::SSLeay to be installed (it will be loaded	413	TLS mode requires Net::SSLeay to be installed (it will be loaded
179	automatically when you try to create a TLS handle).	414	automatically when you try to create a TLS handle): this module doesn't
		415	have a dependency on that module, so if your module requires it, you have
		416	to add the dependency yourself.
180		417
181	For the TLS server side, use C<accept>, and for the TLS client side of a	418	Unlike TCP, TLS has a server and client side: for the TLS server side, use
182	connection, use C<connect> mode.	419	C<accept>, and for the TLS client side of a connection, use C<connect>
		420	mode.
183		421
184	You can also provide your own TLS connection object, but you have	422	You can also provide your own TLS connection object, but you have
185	to make sure that you call either C<Net::SSLeay::set_connect_state>	423	to make sure that you call either C<Net::SSLeay::set_connect_state>
186	or C<Net::SSLeay::set_accept_state> on it before you pass it to	424	or C<Net::SSLeay::set_accept_state> on it before you pass it to
187	AnyEvent::Handle.	425	AnyEvent::Handle. Also, this module will take ownership of this connection
		426	object.
188		427
		428	At some future point, AnyEvent::Handle might switch to another TLS
		429	implementation, then the option to use your own session object will go
		430	away.
		431
		432	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		433	passing in the wrong integer will lead to certain crash. This most often
		434	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		435	segmentation fault.
		436
189	See the C<starttls> method if you need to start TLs negotiation later.	437	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
190		438
191	=item tls_ctx => $ssl_ctx	439	=item tls_ctx => $anyevent_tls
192		440
193	Use the given Net::SSLeay::CTX object to create the new TLS connection	441	Use the given C<AnyEvent::TLS> object to create the new TLS connection
194	(unless a connection object was specified directly). If this parameter is	442	(unless a connection object was specified directly). If this
195	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	443	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		444	C<AnyEvent::Handle::TLS_CTX>.
		445
		446	Instead of an object, you can also specify a hash reference with C<< key
		447	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		448	new TLS context object.
		449
		450	=item on_starttls => $cb->($handle, $success[, $error_message])
		451
		452	This callback will be invoked when the TLS/SSL handshake has finished. If
		453	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		454	(C<on_stoptls> will not be called in this case).
		455
		456	The session in C<< $handle->{tls} >> can still be examined in this
		457	callback, even when the handshake was not successful.
		458
		459	TLS handshake failures will not cause C<on_error> to be invoked when this
		460	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		461
		462	Without this callback, handshake failures lead to C<on_error> being
		463	called as usual.
		464
		465	Note that you cannot just call C<starttls> again in this callback. If you
		466	need to do that, start an zero-second timer instead whose callback can
		467	then call C<< ->starttls >> again.
		468
		469	=item on_stoptls => $cb->($handle)
		470
		471	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		472	set, then it will be invoked after freeing the TLS session. If it is not,
		473	then a TLS shutdown condition will be treated like a normal EOF condition
		474	on the handle.
		475
		476	The session in C<< $handle->{tls} >> can still be examined in this
		477	callback.
		478
		479	This callback will only be called on TLS shutdowns, not when the
		480	underlying handle signals EOF.
196		481
197	=item json => JSON or JSON::XS object	482	=item json => JSON or JSON::XS object
198		483
199	This is the json coder object used by the C<json> read and write types.	484	This is the json coder object used by the C<json> read and write types.
200		485
201	If you don't supply it, then AnyEvent::Handle will create and use a	486	If you don't supply it, then AnyEvent::Handle will create and use a
202	suitable one, which will write and expect UTF-8 encoded JSON texts.	487	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		488	texts.
203		489
204	Note that you are responsible to depend on the JSON module if you want to	490	Note that you are responsible to depend on the JSON module if you want to
205	use this functionality, as AnyEvent does not have a dependency itself.	491	use this functionality, as AnyEvent does not have a dependency itself.
206		492
207	=item filter_r => $cb
208
209	=item filter_w => $cb
210
211	These exist, but are undocumented at this time.
212
213	=back	493	=back
214		494
215	=cut	495	=cut
216		496
217	sub new {	497	sub new {
218	my $class = shift;	498	my $class = shift;
219
220	my $self = bless { @_ }, $class;	499	my $self = bless { @_ }, $class;
221		500
222	$self->{fh} or Carp::croak "mandatory argument fh is missing";	501	if ($self->{fh}) {
		502	$self->_start;
		503	return unless $self->{fh}; # could be gone by now
		504
		505	} elsif ($self->{connect}) {
		506	require AnyEvent::Socket;
		507
		508	$self->{peername} = $self->{connect}[0]
		509	unless exists $self->{peername};
		510
		511	$self->{_skip_drain_rbuf} = 1;
		512
		513	{
		514	Scalar::Util::weaken (my $self = $self);
		515
		516	$self->{_connect} =
		517	AnyEvent::Socket::tcp_connect (
		518	$self->{connect}[0],
		519	$self->{connect}[1],
		520	sub {
		521	my ($fh, $host, $port, $retry) = @_;
		522
		523	delete $self->{_connect}; # no longer needed
		524
		525	if ($fh) {
		526	$self->{fh} = $fh;
		527
		528	delete $self->{_skip_drain_rbuf};
		529	$self->_start;
		530
		531	$self->{on_connect}
		532	and $self->{on_connect}($self, $host, $port, sub {
		533	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		534	$self->{_skip_drain_rbuf} = 1;
		535	&$retry;
		536	});
		537
		538	} else {
		539	if ($self->{on_connect_error}) {
		540	$self->{on_connect_error}($self, "$!");
		541	$self->destroy;
		542	} else {
		543	$self->_error ($!, 1);
		544	}
		545	}
		546	},
		547	sub {
		548	local $self->{fh} = $_[0];
		549
		550	$self->{on_prepare}
		551	? $self->{on_prepare}->($self)
		552	: ()
		553	}
		554	);
		555	}
		556
		557	} else {
		558	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		559	}
		560
		561	$self
		562	}
		563
		564	sub _start {
		565	my ($self) = @_;
		566
		567	# too many clueless people try to use udp and similar sockets
		568	# with AnyEvent::Handle, do them a favour.
		569	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		570	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		571	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
223		572
224	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	573	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
225		574
226	if ($self->{tls}) {	575	$self->{_activity} =
227	require Net::SSLeay;	576	$self->{_ractivity} =
		577	$self->{_wactivity} = AE::now;
		578
		579	$self->{read_size} ||= 2048;
		580	$self->{max_read_size} = $self->{read_size}
		581	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		582
		583	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		584	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		585	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		586
		587	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		588	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		589
		590	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		591
228	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	592	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
229	}	593	if $self->{tls};
230		594
231	$self->{_activity} = AnyEvent->now;
232	$self->_timeout;
233
234	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	595	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
235		596
236	$self	597	$self->start_read
237	}	598	if $self->{on_read} || @{ $self->{_queue} };
238		599
239	sub _shutdown {	600	$self->_drain_wbuf;
240	my ($self) = @_;
241
242	delete $self->{_tw};
243	delete $self->{_rw};
244	delete $self->{_ww};
245	delete $self->{fh};
246
247	$self->stoptls;
248	}	601	}
249		602
250	sub _error {	603	sub _error {
251	my ($self, $errno, $fatal) = @_;	604	my ($self, $errno, $fatal, $message) = @_;
252
253	$self->_shutdown
254	if $fatal;
255		605
256	$! = $errno;	606	$! = $errno;
		607	$message ||= "$!";
257		608
258	if ($self->{on_error}) {	609	if ($self->{on_error}) {
259	$self->{on_error}($self, $fatal);	610	$self->{on_error}($self, $fatal, $message);
260	} else {	611	$self->destroy if $fatal;
		612	} elsif ($self->{fh} || $self->{connect}) {
		613	$self->destroy;
261	Carp::croak "AnyEvent::Handle uncaught error: $!";	614	Carp::croak "AnyEvent::Handle uncaught error: $message";
262	}	615	}
263	}	616	}
264		617
265	=item $fh = $handle->fh	618	=item $fh = $handle->fh
266		619
267	This method returns the file handle of the L<AnyEvent::Handle> object.	620	This method returns the file handle used to create the L<AnyEvent::Handle> object.
268		621
269	=cut	622	=cut
270		623
271	sub fh { $_[0]{fh} }	624	sub fh { $_[0]{fh} }
272		625
…		…
290	$_[0]{on_eof} = $_[1];	643	$_[0]{on_eof} = $_[1];
291	}	644	}
292		645
293	=item $handle->on_timeout ($cb)	646	=item $handle->on_timeout ($cb)
294		647
295	Replace the current C<on_timeout> callback, or disables the callback	648	=item $handle->on_rtimeout ($cb)
296	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
297	argument.
298		649
299	=cut	650	=item $handle->on_wtimeout ($cb)
300		651
		652	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		653	callback, or disables the callback (but not the timeout) if C<$cb> =
		654	C<undef>. See the C<timeout> constructor argument and method.
		655
		656	=cut
		657
		658	# see below
		659
		660	=item $handle->autocork ($boolean)
		661
		662	Enables or disables the current autocork behaviour (see C<autocork>
		663	constructor argument). Changes will only take effect on the next write.
		664
		665	=cut
		666
		667	sub autocork {
		668	$_[0]{autocork} = $_[1];
		669	}
		670
		671	=item $handle->no_delay ($boolean)
		672
		673	Enables or disables the C<no_delay> setting (see constructor argument of
		674	the same name for details).
		675
		676	=cut
		677
		678	sub no_delay {
		679	$_[0]{no_delay} = $_[1];
		680
		681	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		682	if $_[0]{fh};
		683	}
		684
		685	=item $handle->keepalive ($boolean)
		686
		687	Enables or disables the C<keepalive> setting (see constructor argument of
		688	the same name for details).
		689
		690	=cut
		691
		692	sub keepalive {
		693	$_[0]{keepalive} = $_[1];
		694
		695	eval {
		696	local $SIG{__DIE__};
		697	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		698	if $_[0]{fh};
		699	};
		700	}
		701
		702	=item $handle->oobinline ($boolean)
		703
		704	Enables or disables the C<oobinline> setting (see constructor argument of
		705	the same name for details).
		706
		707	=cut
		708
		709	sub oobinline {
		710	$_[0]{oobinline} = $_[1];
		711
		712	eval {
		713	local $SIG{__DIE__};
		714	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		715	if $_[0]{fh};
		716	};
		717	}
		718
		719	=item $handle->keepalive ($boolean)
		720
		721	Enables or disables the C<keepalive> setting (see constructor argument of
		722	the same name for details).
		723
		724	=cut
		725
		726	sub keepalive {
		727	$_[0]{keepalive} = $_[1];
		728
		729	eval {
		730	local $SIG{__DIE__};
		731	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		732	if $_[0]{fh};
		733	};
		734	}
		735
		736	=item $handle->on_starttls ($cb)
		737
		738	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		739
		740	=cut
		741
		742	sub on_starttls {
		743	$_[0]{on_starttls} = $_[1];
		744	}
		745
		746	=item $handle->on_stoptls ($cb)
		747
		748	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		749
		750	=cut
		751
301	sub on_timeout {	752	sub on_stoptls {
302	$_[0]{on_timeout} = $_[1];	753	$_[0]{on_stoptls} = $_[1];
		754	}
		755
		756	=item $handle->rbuf_max ($max_octets)
		757
		758	Configures the C<rbuf_max> setting (C<undef> disables it).
		759
		760	=item $handle->wbuf_max ($max_octets)
		761
		762	Configures the C<wbuf_max> setting (C<undef> disables it).
		763
		764	=cut
		765
		766	sub rbuf_max {
		767	$_[0]{rbuf_max} = $_[1];
		768	}
		769
		770	sub wbuf_max {
		771	$_[0]{wbuf_max} = $_[1];
303	}	772	}
304		773
305	#############################################################################	774	#############################################################################
306		775
307	=item $handle->timeout ($seconds)	776	=item $handle->timeout ($seconds)
308		777
		778	=item $handle->rtimeout ($seconds)
		779
		780	=item $handle->wtimeout ($seconds)
		781
309	Configures (or disables) the inactivity timeout.	782	Configures (or disables) the inactivity timeout.
310		783
311	=cut	784	=item $handle->timeout_reset
312		785
313	sub timeout {	786	=item $handle->rtimeout_reset
		787
		788	=item $handle->wtimeout_reset
		789
		790	Reset the activity timeout, as if data was received or sent.
		791
		792	These methods are cheap to call.
		793
		794	=cut
		795
		796	for my $dir ("", "r", "w") {
		797	my $timeout = "${dir}timeout";
		798	my $tw = "_${dir}tw";
		799	my $on_timeout = "on_${dir}timeout";
		800	my $activity = "_${dir}activity";
		801	my $cb;
		802
		803	*$on_timeout = sub {
		804	$_[0]{$on_timeout} = $_[1];
		805	};
		806
		807	*$timeout = sub {
314	my ($self, $timeout) = @_;	808	my ($self, $new_value) = @_;
315		809
		810	$new_value >= 0
		811	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		812
316	$self->{timeout} = $timeout;	813	$self->{$timeout} = $new_value;
317	$self->_timeout;	814	delete $self->{$tw}; &$cb;
318	}	815	};
319		816
		817	*{"${dir}timeout_reset"} = sub {
		818	$_[0]{$activity} = AE::now;
		819	};
		820
		821	# main workhorse:
320	# reset the timeout watcher, as neccessary	822	# reset the timeout watcher, as neccessary
321	# also check for time-outs	823	# also check for time-outs
322	sub _timeout {	824	$cb = sub {
323	my ($self) = @_;	825	my ($self) = @_;
324		826
325	if ($self->{timeout}) {	827	if ($self->{$timeout} && $self->{fh}) {
326	my $NOW = AnyEvent->now;	828	my $NOW = AE::now;
327		829
328	# when would the timeout trigger?	830	# when would the timeout trigger?
329	my $after = $self->{_activity} + $self->{timeout} - $NOW;	831	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
330		832
331	# now or in the past already?	833	# now or in the past already?
332	if ($after <= 0) {	834	if ($after <= 0) {
333	$self->{_activity} = $NOW;	835	$self->{$activity} = $NOW;
334		836
335	if ($self->{on_timeout}) {	837	if ($self->{$on_timeout}) {
336	$self->{on_timeout}($self);	838	$self->{$on_timeout}($self);
337	} else {	839	} else {
338	$self->_error (&Errno::ETIMEDOUT);	840	$self->_error (Errno::ETIMEDOUT);
		841	}
		842
		843	# callback could have changed timeout value, optimise
		844	return unless $self->{$timeout};
		845
		846	# calculate new after
		847	$after = $self->{$timeout};
339	}	848	}
340		849
341	# callback could have changed timeout value, optimise	850	Scalar::Util::weaken $self;
342	return unless $self->{timeout};	851	return unless $self; # ->error could have destroyed $self
343		852
344	# calculate new after	853	$self->{$tw} ||= AE::timer $after, 0, sub {
345	$after = $self->{timeout};	854	delete $self->{$tw};
		855	$cb->($self);
		856	};
		857	} else {
		858	delete $self->{$tw};
346	}	859	}
347
348	Scalar::Util::weaken $self;
349	return unless $self; # ->error could have destroyed $self
350
351	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
352	delete $self->{_tw};
353	$self->_timeout;
354	});
355	} else {
356	delete $self->{_tw};
357	}	860	}
358	}	861	}
359		862
360	#############################################################################	863	#############################################################################
361		864
…		…
377	=item $handle->on_drain ($cb)	880	=item $handle->on_drain ($cb)
378		881
379	Sets the C<on_drain> callback or clears it (see the description of	882	Sets the C<on_drain> callback or clears it (see the description of
380	C<on_drain> in the constructor).	883	C<on_drain> in the constructor).
381		884
		885	This method may invoke callbacks (and therefore the handle might be
		886	destroyed after it returns).
		887
382	=cut	888	=cut
383		889
384	sub on_drain {	890	sub on_drain {
385	my ($self, $cb) = @_;	891	my ($self, $cb) = @_;
386		892
387	$self->{on_drain} = $cb;	893	$self->{on_drain} = $cb;
388		894
389	$cb->($self)	895	$cb->($self)
390	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	896	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
391	}	897	}
392		898
393	=item $handle->push_write ($data)	899	=item $handle->push_write ($data)
394		900
395	Queues the given scalar to be written. You can push as much data as you	901	Queues the given scalar to be written. You can push as much data as
396	want (only limited by the available memory), as C<AnyEvent::Handle>	902	you want (only limited by the available memory and C<wbuf_max>), as
397	buffers it independently of the kernel.	903	C<AnyEvent::Handle> buffers it independently of the kernel.
		904
		905	This method may invoke callbacks (and therefore the handle might be
		906	destroyed after it returns).
398		907
399	=cut	908	=cut
400		909
401	sub _drain_wbuf {	910	sub _drain_wbuf {
402	my ($self) = @_;	911	my ($self) = @_;
…		…
406	Scalar::Util::weaken $self;	915	Scalar::Util::weaken $self;
407		916
408	my $cb = sub {	917	my $cb = sub {
409	my $len = syswrite $self->{fh}, $self->{wbuf};	918	my $len = syswrite $self->{fh}, $self->{wbuf};
410		919
411	if ($len >= 0) {	920	if (defined $len) {
412	substr $self->{wbuf}, 0, $len, "";	921	substr $self->{wbuf}, 0, $len, "";
413		922
414	$self->{_activity} = AnyEvent->now;	923	$self->{_activity} = $self->{_wactivity} = AE::now;
415		924
416	$self->{on_drain}($self)	925	$self->{on_drain}($self)
417	if $self->{low_water_mark} >= length $self->{wbuf}	926	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
418	&& $self->{on_drain};	927	&& $self->{on_drain};
419		928
420	delete $self->{_ww} unless length $self->{wbuf};	929	delete $self->{_ww} unless length $self->{wbuf};
421	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	930	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
422	$self->_error ($!, 1);	931	$self->_error ($!, 1);
423	}	932	}
424	};	933	};
425		934
426	# try to write data immediately	935	# try to write data immediately
427	$cb->();	936	$cb->() unless $self->{autocork};
428		937
429	# if still data left in wbuf, we need to poll	938	# if still data left in wbuf, we need to poll
430	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	939	$self->{_ww} = AE::io $self->{fh}, 1, $cb
431	if length $self->{wbuf};	940	if length $self->{wbuf};
		941
		942	if (
		943	defined $self->{wbuf_max}
		944	&& $self->{wbuf_max} < length $self->{wbuf}
		945	) {
		946	$self->_error (Errno::ENOSPC, 1), return;
		947	}
432	};	948	};
433	}	949	}
434		950
435	our %WH;	951	our %WH;
436		952
		953	# deprecated
437	sub register_write_type($$) {	954	sub register_write_type($$) {
438	$WH{$_[0]} = $_[1];	955	$WH{$_[0]} = $_[1];
439	}	956	}
440		957
441	sub push_write {	958	sub push_write {
442	my $self = shift;	959	my $self = shift;
443		960
444	if (@_ > 1) {	961	if (@_ > 1) {
445	my $type = shift;	962	my $type = shift;
446		963
		964	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
447	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	965	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
448	->($self, @_);	966	->($self, @_);
449	}	967	}
450		968
		969	# we downgrade here to avoid hard-to-track-down bugs,
		970	# and diagnose the problem earlier and better.
		971
451	if ($self->{filter_w}) {	972	if ($self->{tls}) {
452	$self->{filter_w}($self, \$_[0]);	973	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		974	&_dotls ($self) if $self->{fh};
453	} else {	975	} else {
454	$self->{wbuf} .= $_[0];	976	utf8::downgrade $self->{wbuf} .= $_[0];
455	$self->_drain_wbuf;	977	$self->_drain_wbuf if $self->{fh};
456	}	978	}
457	}	979	}
458		980
459	=item $handle->push_write (type => @args)	981	=item $handle->push_write (type => @args)
460		982
461	Instead of formatting your data yourself, you can also let this module do	983	Instead of formatting your data yourself, you can also let this module
462	the job by specifying a type and type-specific arguments.	984	do the job by specifying a type and type-specific arguments. You
		985	can also specify the (fully qualified) name of a package, in which
		986	case AnyEvent tries to load the package and then expects to find the
		987	C<anyevent_write_type> function inside (see "custom write types", below).
463		988
464	Predefined types are (if you have ideas for additional types, feel free to	989	Predefined types are (if you have ideas for additional types, feel free to
465	drop by and tell us):	990	drop by and tell us):
466		991
467	=over 4	992	=over 4
…		…
474	=cut	999	=cut
475		1000
476	register_write_type netstring => sub {	1001	register_write_type netstring => sub {
477	my ($self, $string) = @_;	1002	my ($self, $string) = @_;
478		1003
479	sprintf "%d:%s,", (length $string), $string	1004	(length $string) . ":$string,"
480	};	1005	};
481		1006
482	=item packstring => $format, $data	1007	=item packstring => $format, $data
483		1008
484	An octet string prefixed with an encoded length. The encoding C<$format>	1009	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
489	=cut	1014	=cut
490		1015
491	register_write_type packstring => sub {	1016	register_write_type packstring => sub {
492	my ($self, $format, $string) = @_;	1017	my ($self, $format, $string) = @_;
493		1018
494	pack "$format/a", $string	1019	pack "$format/a*", $string
495	};	1020	};
496		1021
497	=item json => $array_or_hashref	1022	=item json => $array_or_hashref
498		1023
499	Encodes the given hash or array reference into a JSON object. Unless you	1024	Encodes the given hash or array reference into a JSON object. Unless you
…		…
524	Other languages could read single lines terminated by a newline and pass	1049	Other languages could read single lines terminated by a newline and pass
525	this line into their JSON decoder of choice.	1050	this line into their JSON decoder of choice.
526		1051
527	=cut	1052	=cut
528		1053
		1054	sub json_coder() {
		1055	eval { require JSON::XS; JSON::XS->new->utf8 }
		1056	|| do { require JSON; JSON->new->utf8 }
		1057	}
		1058
529	register_write_type json => sub {	1059	register_write_type json => sub {
530	my ($self, $ref) = @_;	1060	my ($self, $ref) = @_;
531		1061
532	require JSON;	1062	my $json = $self->{json} ||= json_coder;
533		1063
534	$self->{json} ? $self->{json}->encode ($ref)	1064	$json->encode ($ref)
535	: JSON::encode_json ($ref)
536	};	1065	};
537		1066
		1067	=item storable => $reference
		1068
		1069	Freezes the given reference using L<Storable> and writes it to the
		1070	handle. Uses the C<nfreeze> format.
		1071
		1072	=cut
		1073
		1074	register_write_type storable => sub {
		1075	my ($self, $ref) = @_;
		1076
		1077	require Storable;
		1078
		1079	pack "w/a*", Storable::nfreeze ($ref)
		1080	};
		1081
538	=back	1082	=back
539		1083
540	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	1084	=item $handle->push_shutdown
541		1085
542	This function (not method) lets you add your own types to C<push_write>.	1086	Sometimes you know you want to close the socket after writing your data
		1087	before it was actually written. One way to do that is to replace your
		1088	C<on_drain> handler by a callback that shuts down the socket (and set
		1089	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1090	replaces the C<on_drain> callback with:
		1091
		1092	sub { shutdown $_[0]{fh}, 1 }
		1093
		1094	This simply shuts down the write side and signals an EOF condition to the
		1095	the peer.
		1096
		1097	You can rely on the normal read queue and C<on_eof> handling
		1098	afterwards. This is the cleanest way to close a connection.
		1099
		1100	This method may invoke callbacks (and therefore the handle might be
		1101	destroyed after it returns).
		1102
		1103	=cut
		1104
		1105	sub push_shutdown {
		1106	my ($self) = @_;
		1107
		1108	delete $self->{low_water_mark};
		1109	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1110	}
		1111
		1112	=item custom write types - Package::anyevent_write_type $handle, @args
		1113
		1114	Instead of one of the predefined types, you can also specify the name of
		1115	a package. AnyEvent will try to load the package and then expects to find
		1116	a function named C<anyevent_write_type> inside. If it isn't found, it
		1117	progressively tries to load the parent package until it either finds the
		1118	function (good) or runs out of packages (bad).
		1119
543	Whenever the given C<type> is used, C<push_write> will invoke the code	1120	Whenever the given C<type> is used, C<push_write> will the function with
544	reference with the handle object and the remaining arguments.	1121	the handle object and the remaining arguments.
545		1122
546	The code reference is supposed to return a single octet string that will	1123	The function is supposed to return a single octet string that will be
547	be appended to the write buffer.	1124	appended to the write buffer, so you cna mentally treat this function as a
		1125	"arguments to on-the-wire-format" converter.
548		1126
549	Note that this is a function, and all types registered this way will be	1127	Example: implement a custom write type C<join> that joins the remaining
550	global, so try to use unique names.	1128	arguments using the first one.
		1129
		1130	$handle->push_write (My::Type => " ", 1,2,3);
		1131
		1132	# uses the following package, which can be defined in the "My::Type" or in
		1133	# the "My" modules to be auto-loaded, or just about anywhere when the
		1134	# My::Type::anyevent_write_type is defined before invoking it.
		1135
		1136	package My::Type;
		1137
		1138	sub anyevent_write_type {
		1139	my ($handle, $delim, @args) = @_;
		1140
		1141	join $delim, @args
		1142	}
551		1143
552	=cut	1144	=cut
553		1145
554	#############################################################################	1146	#############################################################################
555		1147
…		…
564	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1156	ways, the "simple" way, using only C<on_read> and the "complex" way, using
565	a queue.	1157	a queue.
566		1158
567	In the simple case, you just install an C<on_read> callback and whenever	1159	In the simple case, you just install an C<on_read> callback and whenever
568	new data arrives, it will be called. You can then remove some data (if	1160	new data arrives, it will be called. You can then remove some data (if
569	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	1161	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
570	or not.	1162	leave the data there if you want to accumulate more (e.g. when only a
		1163	partial message has been received so far), or change the read queue with
		1164	e.g. C<push_read>.
571		1165
572	In the more complex case, you want to queue multiple callbacks. In this	1166	In the more complex case, you want to queue multiple callbacks. In this
573	case, AnyEvent::Handle will call the first queued callback each time new	1167	case, AnyEvent::Handle will call the first queued callback each time new
574	data arrives (also the first time it is queued) and removes it when it has	1168	data arrives (also the first time it is queued) and remove it when it has
575	done its job (see C<push_read>, below).	1169	done its job (see C<push_read>, below).
576		1170
577	This way you can, for example, push three line-reads, followed by reading	1171	This way you can, for example, push three line-reads, followed by reading
578	a chunk of data, and AnyEvent::Handle will execute them in order.	1172	a chunk of data, and AnyEvent::Handle will execute them in order.
579		1173
…		…
593	# handle xml	1187	# handle xml
594	});	1188	});
595	});	1189	});
596	});	1190	});
597		1191
598	Example 2: Implement a client for a protocol that replies either with	1192	Example 2: Implement a client for a protocol that replies either with "OK"
599	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1193	and another line or "ERROR" for the first request that is sent, and 64
600	second request. Due tot he availability of a full queue, we can just	1194	bytes for the second request. Due to the availability of a queue, we can
601	pipeline sending both requests and manipulate the queue as necessary in	1195	just pipeline sending both requests and manipulate the queue as necessary
602	the callbacks:	1196	in the callbacks.
603		1197
604	# request one	1198	When the first callback is called and sees an "OK" response, it will
		1199	C<unshift> another line-read. This line-read will be queued I<before> the
		1200	64-byte chunk callback.
		1201
		1202	# request one, returns either "OK + extra line" or "ERROR"
605	$handle->push_write ("request 1\015\012");	1203	$handle->push_write ("request 1\015\012");
606		1204
607	# we expect "ERROR" or "OK" as response, so push a line read	1205	# we expect "ERROR" or "OK" as response, so push a line read
608	$handle->push_read (line => sub {	1206	$handle->push_read (line => sub {
609	# if we got an "OK", we have to _prepend_ another line,	1207	# if we got an "OK", we have to _prepend_ another line,
…		…
616	...	1214	...
617	});	1215	});
618	}	1216	}
619	});	1217	});
620		1218
621	# request two	1219	# request two, simply returns 64 octets
622	$handle->push_write ("request 2\015\012");	1220	$handle->push_write ("request 2\015\012");
623		1221
624	# simply read 64 bytes, always	1222	# simply read 64 bytes, always
625	$handle->push_read (chunk => 64, sub {	1223	$handle->push_read (chunk => 64, sub {
626	my $response = $_[1];	1224	my $response = $_[1];
…		…
632	=cut	1230	=cut
633		1231
634	sub _drain_rbuf {	1232	sub _drain_rbuf {
635	my ($self) = @_;	1233	my ($self) = @_;
636		1234
		1235	# avoid recursion
		1236	return if $self->{_skip_drain_rbuf};
637	local $self->{_in_drain} = 1;	1237	local $self->{_skip_drain_rbuf} = 1;
638
639	if (
640	defined $self->{rbuf_max}
641	&& $self->{rbuf_max} < length $self->{rbuf}
642	) {
643	return $self->_error (&Errno::ENOSPC, 1);
644	}
645		1238
646	while () {	1239	while () {
647	no strict 'refs';	1240	# we need to use a separate tls read buffer, as we must not receive data while
		1241	# we are draining the buffer, and this can only happen with TLS.
		1242	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1243	if exists $self->{_tls_rbuf};
648		1244
649	my $len = length $self->{rbuf};	1245	my $len = length $self->{rbuf};
650		1246
651	if (my $cb = shift @{ $self->{_queue} }) {	1247	if (my $cb = shift @{ $self->{_queue} }) {
652	unless ($cb->($self)) {	1248	unless ($cb->($self)) {
653	if ($self->{_eof}) {	1249	# no progress can be made
654	# no progress can be made (not enough data and no data forthcoming)	1250	# (not enough data and no data forthcoming)
655	$self->_error (&Errno::EPIPE, 1), last;	1251	$self->_error (Errno::EPIPE, 1), return
656	}	1252	if $self->{_eof};
657		1253
658	unshift @{ $self->{_queue} }, $cb;	1254	unshift @{ $self->{_queue} }, $cb;
659	last;	1255	last;
660	}	1256	}
661	} elsif ($self->{on_read}) {	1257	} elsif ($self->{on_read}) {
…		…
668	&& !@{ $self->{_queue} } # and the queue is still empty	1264	&& !@{ $self->{_queue} } # and the queue is still empty
669	&& $self->{on_read} # but we still have on_read	1265	&& $self->{on_read} # but we still have on_read
670	) {	1266	) {
671	# no further data will arrive	1267	# no further data will arrive
672	# so no progress can be made	1268	# so no progress can be made
673	$self->_error (&Errno::EPIPE, 1), last	1269	$self->_error (Errno::EPIPE, 1), return
674	if $self->{_eof};	1270	if $self->{_eof};
675		1271
676	last; # more data might arrive	1272	last; # more data might arrive
677	}	1273	}
678	} else {	1274	} else {
679	# read side becomes idle	1275	# read side becomes idle
680	delete $self->{_rw};	1276	delete $self->{_rw} unless $self->{tls};
681	last;	1277	last;
682	}	1278	}
683	}	1279	}
684		1280
		1281	if ($self->{_eof}) {
		1282	$self->{on_eof}
685	$self->{on_eof}($self)	1283	? $self->{on_eof}($self)
686	if $self->{_eof} && $self->{on_eof};	1284	: $self->_error (0, 1, "Unexpected end-of-file");
		1285
		1286	return;
		1287	}
		1288
		1289	if (
		1290	defined $self->{rbuf_max}
		1291	&& $self->{rbuf_max} < length $self->{rbuf}
		1292	) {
		1293	$self->_error (Errno::ENOSPC, 1), return;
		1294	}
687		1295
688	# may need to restart read watcher	1296	# may need to restart read watcher
689	unless ($self->{_rw}) {	1297	unless ($self->{_rw}) {
690	$self->start_read	1298	$self->start_read
691	if $self->{on_read} || @{ $self->{_queue} };	1299	if $self->{on_read} || @{ $self->{_queue} };
…		…
696		1304
697	This replaces the currently set C<on_read> callback, or clears it (when	1305	This replaces the currently set C<on_read> callback, or clears it (when
698	the new callback is C<undef>). See the description of C<on_read> in the	1306	the new callback is C<undef>). See the description of C<on_read> in the
699	constructor.	1307	constructor.
700		1308
		1309	This method may invoke callbacks (and therefore the handle might be
		1310	destroyed after it returns).
		1311
701	=cut	1312	=cut
702		1313
703	sub on_read {	1314	sub on_read {
704	my ($self, $cb) = @_;	1315	my ($self, $cb) = @_;
705		1316
706	$self->{on_read} = $cb;	1317	$self->{on_read} = $cb;
707	$self->_drain_rbuf if $cb && !$self->{_in_drain};	1318	$self->_drain_rbuf if $cb;
708	}	1319	}
709		1320
710	=item $handle->rbuf	1321	=item $handle->rbuf
711		1322
712	Returns the read buffer (as a modifiable lvalue).	1323	Returns the read buffer (as a modifiable lvalue). You can also access the
		1324	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1325	much faster, and no less clean).
713		1326
714	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1327	The only operation allowed on the read buffer (apart from looking at it)
715	you want.	1328	is removing data from its beginning. Otherwise modifying or appending to
		1329	it is not allowed and will lead to hard-to-track-down bugs.
716		1330
717	NOTE: The read buffer should only be used or modified if the C<on_read>,	1331	NOTE: The read buffer should only be used or modified in the C<on_read>
718	C<push_read> or C<unshift_read> methods are used. The other read methods	1332	callback or when C<push_read> or C<unshift_read> are used with a single
719	automatically manage the read buffer.	1333	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1334	will manage the read buffer on their own.
720		1335
721	=cut	1336	=cut
722		1337
723	sub rbuf : lvalue {	1338	sub rbuf : lvalue {
724	$_[0]{rbuf}	1339	$_[0]{rbuf}
…		…
741		1356
742	If enough data was available, then the callback must remove all data it is	1357	If enough data was available, then the callback must remove all data it is
743	interested in (which can be none at all) and return a true value. After returning	1358	interested in (which can be none at all) and return a true value. After returning
744	true, it will be removed from the queue.	1359	true, it will be removed from the queue.
745		1360
		1361	These methods may invoke callbacks (and therefore the handle might be
		1362	destroyed after it returns).
		1363
746	=cut	1364	=cut
747		1365
748	our %RH;	1366	our %RH;
749		1367
750	sub register_read_type($$) {	1368	sub register_read_type($$) {
…		…
756	my $cb = pop;	1374	my $cb = pop;
757		1375
758	if (@_) {	1376	if (@_) {
759	my $type = shift;	1377	my $type = shift;
760		1378
		1379	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
761	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1380	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
762	->($self, $cb, @_);	1381	->($self, $cb, @_);
763	}	1382	}
764		1383
765	push @{ $self->{_queue} }, $cb;	1384	push @{ $self->{_queue} }, $cb;
766	$self->_drain_rbuf unless $self->{_in_drain};	1385	$self->_drain_rbuf;
767	}	1386	}
768		1387
769	sub unshift_read {	1388	sub unshift_read {
770	my $self = shift;	1389	my $self = shift;
771	my $cb = pop;	1390	my $cb = pop;
772		1391
773	if (@_) {	1392	if (@_) {
774	my $type = shift;	1393	my $type = shift;
775		1394
		1395	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
776	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1396	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
777	->($self, $cb, @_);	1397	->($self, $cb, @_);
778	}	1398	}
779		1399
780
781	unshift @{ $self->{_queue} }, $cb;	1400	unshift @{ $self->{_queue} }, $cb;
782	$self->_drain_rbuf unless $self->{_in_drain};	1401	$self->_drain_rbuf;
783	}	1402	}
784		1403
785	=item $handle->push_read (type => @args, $cb)	1404	=item $handle->push_read (type => @args, $cb)
786		1405
787	=item $handle->unshift_read (type => @args, $cb)	1406	=item $handle->unshift_read (type => @args, $cb)
788		1407
789	Instead of providing a callback that parses the data itself you can chose	1408	Instead of providing a callback that parses the data itself you can chose
790	between a number of predefined parsing formats, for chunks of data, lines	1409	between a number of predefined parsing formats, for chunks of data, lines
791	etc.	1410	etc. You can also specify the (fully qualified) name of a package, in
		1411	which case AnyEvent tries to load the package and then expects to find the
		1412	C<anyevent_read_type> function inside (see "custom read types", below).
792		1413
793	Predefined types are (if you have ideas for additional types, feel free to	1414	Predefined types are (if you have ideas for additional types, feel free to
794	drop by and tell us):	1415	drop by and tell us):
795		1416
796	=over 4	1417	=over 4
…		…
817	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1438	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
818	1	1439	1
819	}	1440	}
820	};	1441	};
821		1442
822	# compatibility with older API
823	sub push_read_chunk {
824	$_[0]->push_read (chunk => $_[1], $_[2]);
825	}
826
827	sub unshift_read_chunk {
828	$_[0]->unshift_read (chunk => $_[1], $_[2]);
829	}
830
831	=item line => [$eol, ]$cb->($handle, $line, $eol)	1443	=item line => [$eol, ]$cb->($handle, $line, $eol)
832		1444
833	The callback will be called only once a full line (including the end of	1445	The callback will be called only once a full line (including the end of
834	line marker, C<$eol>) has been read. This line (excluding the end of line	1446	line marker, C<$eol>) has been read. This line (excluding the end of line
835	marker) will be passed to the callback as second argument (C<$line>), and	1447	marker) will be passed to the callback as second argument (C<$line>), and
…		…
850	=cut	1462	=cut
851		1463
852	register_read_type line => sub {	1464	register_read_type line => sub {
853	my ($self, $cb, $eol) = @_;	1465	my ($self, $cb, $eol) = @_;
854		1466
855	$eol = qr|(\015?\012)| if @_ < 3;	1467	if (@_ < 3) {
		1468	# this is more than twice as fast as the generic code below
		1469	sub {
		1470	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		1471
		1472	$cb->($_[0], $1, $2);
		1473	1
		1474	}
		1475	} else {
856	$eol = quotemeta $eol unless ref $eol;	1476	$eol = quotemeta $eol unless ref $eol;
857	$eol = qr|^(.*?)($eol)|s;	1477	$eol = qr|^(.*?)($eol)|s;
858		1478
859	sub {	1479	sub {
860	$_[0]{rbuf} =~ s/$eol// or return;	1480	$_[0]{rbuf} =~ s/$eol// or return;
861		1481
862	$cb->($_[0], $1, $2);	1482	$cb->($_[0], $1, $2);
		1483	1
863	1	1484	}
864	}	1485	}
865	};	1486	};
866
867	# compatibility with older API
868	sub push_read_line {
869	my $self = shift;
870	$self->push_read (line => @_);
871	}
872
873	sub unshift_read_line {
874	my $self = shift;
875	$self->unshift_read (line => @_);
876	}
877		1487
878	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)	1488	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
879		1489
880	Makes a regex match against the regex object C<$accept> and returns	1490	Makes a regex match against the regex object C<$accept> and returns
881	everything up to and including the match.	1491	everything up to and including the match.
…		…
899	the receive buffer when neither C<$accept> nor C<$reject> match,	1509	the receive buffer when neither C<$accept> nor C<$reject> match,
900	and everything preceding and including the match will be accepted	1510	and everything preceding and including the match will be accepted
901	unconditionally. This is useful to skip large amounts of data that you	1511	unconditionally. This is useful to skip large amounts of data that you
902	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1512	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
903	have to start matching from the beginning. This is purely an optimisation	1513	have to start matching from the beginning. This is purely an optimisation
904	and is usually worth only when you expect more than a few kilobytes.	1514	and is usually worth it only when you expect more than a few kilobytes.
905		1515
906	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1516	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
907	expect the header to be very large (it isn't in practise, but...), we use	1517	expect the header to be very large (it isn't in practice, but...), we use
908	a skip regex to skip initial portions. The skip regex is tricky in that	1518	a skip regex to skip initial portions. The skip regex is tricky in that
909	it only accepts something not ending in either \015 or \012, as these are	1519	it only accepts something not ending in either \015 or \012, as these are
910	required for the accept regex.	1520	required for the accept regex.
911		1521
912	$handle->push_read (regex =>	1522	$handle->push_read (regex =>
…		…
931	return 1;	1541	return 1;
932	}	1542	}
933		1543
934	# reject	1544	# reject
935	if ($reject && $$rbuf =~ $reject) {	1545	if ($reject && $$rbuf =~ $reject) {
936	$self->_error (&Errno::EBADMSG);	1546	$self->_error (Errno::EBADMSG);
937	}	1547	}
938		1548
939	# skip	1549	# skip
940	if ($skip && $$rbuf =~ $skip) {	1550	if ($skip && $$rbuf =~ $skip) {
941	$data .= substr $$rbuf, 0, $+[0], "";	1551	$data .= substr $$rbuf, 0, $+[0], "";
…		…
957	my ($self, $cb) = @_;	1567	my ($self, $cb) = @_;
958		1568
959	sub {	1569	sub {
960	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1570	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
961	if ($_[0]{rbuf} =~ /[^0-9]/) {	1571	if ($_[0]{rbuf} =~ /[^0-9]/) {
962	$self->_error (&Errno::EBADMSG);	1572	$self->_error (Errno::EBADMSG);
963	}	1573	}
964	return;	1574	return;
965	}	1575	}
966		1576
967	my $len = $1;	1577	my $len = $1;
…		…
970	my $string = $_[1];	1580	my $string = $_[1];
971	$_[0]->unshift_read (chunk => 1, sub {	1581	$_[0]->unshift_read (chunk => 1, sub {
972	if ($_[1] eq ",") {	1582	if ($_[1] eq ",") {
973	$cb->($_[0], $string);	1583	$cb->($_[0], $string);
974	} else {	1584	} else {
975	$self->_error (&Errno::EBADMSG);	1585	$self->_error (Errno::EBADMSG);
976	}	1586	}
977	});	1587	});
978	});	1588	});
979		1589
980	1	1590	1
…		…
986	An octet string prefixed with an encoded length. The encoding C<$format>	1596	An octet string prefixed with an encoded length. The encoding C<$format>
987	uses the same format as a Perl C<pack> format, but must specify a single	1597	uses the same format as a Perl C<pack> format, but must specify a single
988	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an	1598	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
989	optional C<!>, C<< < >> or C<< > >> modifier).	1599	optional C<!>, C<< < >> or C<< > >> modifier).
990		1600
991	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.	1601	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1602	EPP uses a prefix of C<N> (4 octtes).
992		1603
993	Example: read a block of data prefixed by its length in BER-encoded	1604	Example: read a block of data prefixed by its length in BER-encoded
994	format (very efficient).	1605	format (very efficient).
995		1606
996	$handle->push_read (packstring => "w", sub {	1607	$handle->push_read (packstring => "w", sub {
…		…
1002	register_read_type packstring => sub {	1613	register_read_type packstring => sub {
1003	my ($self, $cb, $format) = @_;	1614	my ($self, $cb, $format) = @_;
1004		1615
1005	sub {	1616	sub {
1006	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method	1617	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1007	defined (my $len = eval { unpack $format, $_[0]->{rbuf} })	1618	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1008	or return;	1619	or return;
1009		1620
		1621	$format = length pack $format, $len;
		1622
		1623	# bypass unshift if we already have the remaining chunk
		1624	if ($format + $len <= length $_[0]{rbuf}) {
		1625	my $data = substr $_[0]{rbuf}, $format, $len;
		1626	substr $_[0]{rbuf}, 0, $format + $len, "";
		1627	$cb->($_[0], $data);
		1628	} else {
1010	# remove prefix	1629	# remove prefix
1011	substr $_[0]->{rbuf}, 0, (length pack $format, $len), "";	1630	substr $_[0]{rbuf}, 0, $format, "";
1012		1631
1013	# read rest	1632	# read remaining chunk
1014	$_[0]->unshift_read (chunk => $len, $cb);	1633	$_[0]->unshift_read (chunk => $len, $cb);
		1634	}
1015		1635
1016	1	1636	1
1017	}	1637	}
1018	};	1638	};
1019		1639
1020	=item json => $cb->($handle, $hash_or_arrayref)	1640	=item json => $cb->($handle, $hash_or_arrayref)
1021		1641
1022	Reads a JSON object or array, decodes it and passes it to the callback.	1642	Reads a JSON object or array, decodes it and passes it to the
		1643	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1023		1644
1024	If a C<json> object was passed to the constructor, then that will be used	1645	If a C<json> object was passed to the constructor, then that will be used
1025	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1646	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1026		1647
1027	This read type uses the incremental parser available with JSON version	1648	This read type uses the incremental parser available with JSON version
…		…
1034	the C<json> write type description, above, for an actual example.	1655	the C<json> write type description, above, for an actual example.
1035		1656
1036	=cut	1657	=cut
1037		1658
1038	register_read_type json => sub {	1659	register_read_type json => sub {
1039	my ($self, $cb, $accept, $reject, $skip) = @_;	1660	my ($self, $cb) = @_;
1040		1661
1041	require JSON;	1662	my $json = $self->{json} ||= json_coder;
1042		1663
1043	my $data;	1664	my $data;
1044	my $rbuf = \$self->{rbuf};	1665	my $rbuf = \$self->{rbuf};
1045		1666
1046	my $json = $self->{json} ||= JSON->new->utf8;
1047
1048	sub {	1667	sub {
1049	my $ref = $json->incr_parse ($self->{rbuf});	1668	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1050		1669
1051	if ($ref) {	1670	if ($ref) {
1052	$self->{rbuf} = $json->incr_text;	1671	$self->{rbuf} = $json->incr_text;
1053	$json->incr_text = "";	1672	$json->incr_text = "";
1054	$cb->($self, $ref);	1673	$cb->($self, $ref);
1055		1674
1056	1	1675	1
		1676	} elsif ($@) {
		1677	# error case
		1678	$json->incr_skip;
		1679
		1680	$self->{rbuf} = $json->incr_text;
		1681	$json->incr_text = "";
		1682
		1683	$self->_error (Errno::EBADMSG);
		1684
		1685	()
1057	} else {	1686	} else {
1058	$self->{rbuf} = "";	1687	$self->{rbuf} = "";
		1688
1059	()	1689	()
1060	}	1690	}
1061	}	1691	}
1062	};	1692	};
1063		1693
		1694	=item storable => $cb->($handle, $ref)
		1695
		1696	Deserialises a L<Storable> frozen representation as written by the
		1697	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1698	data).
		1699
		1700	Raises C<EBADMSG> error if the data could not be decoded.
		1701
		1702	=cut
		1703
		1704	register_read_type storable => sub {
		1705	my ($self, $cb) = @_;
		1706
		1707	require Storable;
		1708
		1709	sub {
		1710	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1711	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1712	or return;
		1713
		1714	my $format = length pack "w", $len;
		1715
		1716	# bypass unshift if we already have the remaining chunk
		1717	if ($format + $len <= length $_[0]{rbuf}) {
		1718	my $data = substr $_[0]{rbuf}, $format, $len;
		1719	substr $_[0]{rbuf}, 0, $format + $len, "";
		1720	$cb->($_[0], Storable::thaw ($data));
		1721	} else {
		1722	# remove prefix
		1723	substr $_[0]{rbuf}, 0, $format, "";
		1724
		1725	# read remaining chunk
		1726	$_[0]->unshift_read (chunk => $len, sub {
		1727	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1728	$cb->($_[0], $ref);
		1729	} else {
		1730	$self->_error (Errno::EBADMSG);
		1731	}
		1732	});
		1733	}
		1734
		1735	1
		1736	}
		1737	};
		1738
1064	=back	1739	=back
1065		1740
1066	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)	1741	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1067		1742
1068	This function (not method) lets you add your own types to C<push_read>.	1743	Instead of one of the predefined types, you can also specify the name
		1744	of a package. AnyEvent will try to load the package and then expects to
		1745	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1746	progressively tries to load the parent package until it either finds the
		1747	function (good) or runs out of packages (bad).
1069		1748
1070	Whenever the given C<type> is used, C<push_read> will invoke the code	1749	Whenever this type is used, C<push_read> will invoke the function with the
1071	reference with the handle object, the callback and the remaining	1750	handle object, the original callback and the remaining arguments.
1072	arguments.
1073		1751
1074	The code reference is supposed to return a callback (usually a closure)	1752	The function is supposed to return a callback (usually a closure) that
1075	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1753	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1754	mentally treat the function as a "configurable read type to read callback"
		1755	converter.
1076		1756
1077	It should invoke the passed callback when it is done reading (remember to	1757	It should invoke the original callback when it is done reading (remember
1078	pass C<$handle> as first argument as all other callbacks do that).	1758	to pass C<$handle> as first argument as all other callbacks do that,
		1759	although there is no strict requirement on this).
1079		1760
1080	Note that this is a function, and all types registered this way will be
1081	global, so try to use unique names.
1082
1083	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1761	For examples, see the source of this module (F<perldoc -m
1084	search for C<register_read_type>)).	1762	AnyEvent::Handle>, search for C<register_read_type>)).
1085		1763
1086	=item $handle->stop_read	1764	=item $handle->stop_read
1087		1765
1088	=item $handle->start_read	1766	=item $handle->start_read
1089		1767
…		…
1095	Note that AnyEvent::Handle will automatically C<start_read> for you when	1773	Note that AnyEvent::Handle will automatically C<start_read> for you when
1096	you change the C<on_read> callback or push/unshift a read callback, and it	1774	you change the C<on_read> callback or push/unshift a read callback, and it
1097	will automatically C<stop_read> for you when neither C<on_read> is set nor	1775	will automatically C<stop_read> for you when neither C<on_read> is set nor
1098	there are any read requests in the queue.	1776	there are any read requests in the queue.
1099		1777
		1778	In older versions of this module (<= 5.3), these methods had no effect,
		1779	as TLS does not support half-duplex connections. In current versions they
		1780	work as expected, as this behaviour is required to avoid certain resource
		1781	attacks, where the program would be forced to read (and buffer) arbitrary
		1782	amounts of data before being able to send some data. The drawback is that
		1783	some readings of the the SSL/TLS specifications basically require this
		1784	attack to be working, as SSL/TLS implementations might stall sending data
		1785	during a rehandshake.
		1786
		1787	As a guideline, during the initial handshake, you should not stop reading,
		1788	and as a client, it might cause problems, depending on your applciation.
		1789
1100	=cut	1790	=cut
1101		1791
1102	sub stop_read {	1792	sub stop_read {
1103	my ($self) = @_;	1793	my ($self) = @_;
1104		1794
…		…
1106	}	1796	}
1107		1797
1108	sub start_read {	1798	sub start_read {
1109	my ($self) = @_;	1799	my ($self) = @_;
1110		1800
1111	unless ($self->{_rw} || $self->{_eof}) {	1801	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1112	Scalar::Util::weaken $self;	1802	Scalar::Util::weaken $self;
1113		1803
1114	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1804	$self->{_rw} = AE::io $self->{fh}, 0, sub {
1115	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1805	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1116	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1806	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1117		1807
1118	if ($len > 0) {	1808	if ($len > 0) {
1119	$self->{_activity} = AnyEvent->now;	1809	$self->{_activity} = $self->{_ractivity} = AE::now;
1120		1810
1121	$self->{filter_r}	1811	if ($self->{tls}) {
1122	? $self->{filter_r}($self, $rbuf)	1812	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1123	: $self->{_in_drain} || $self->_drain_rbuf;	1813
		1814	&_dotls ($self);
		1815	} else {
		1816	$self->_drain_rbuf;
		1817	}
		1818
		1819	if ($len == $self->{read_size}) {
		1820	$self->{read_size} *= 2;
		1821	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1822	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		1823	}
1124		1824
1125	} elsif (defined $len) {	1825	} elsif (defined $len) {
1126	delete $self->{_rw};	1826	delete $self->{_rw};
1127	$self->{_eof} = 1;	1827	$self->{_eof} = 1;
1128	$self->_drain_rbuf unless $self->{_in_drain};	1828	$self->_drain_rbuf;
1129		1829
1130	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1830	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1131	return $self->_error ($!, 1);	1831	return $self->_error ($!, 1);
1132	}	1832	}
1133	});	1833	};
1134	}	1834	}
1135	}	1835	}
1136		1836
		1837	our $ERROR_SYSCALL;
		1838	our $ERROR_WANT_READ;
		1839
		1840	sub _tls_error {
		1841	my ($self, $err) = @_;
		1842
		1843	return $self->_error ($!, 1)
		1844	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1845
		1846	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1847
		1848	# reduce error string to look less scary
		1849	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1850
		1851	if ($self->{_on_starttls}) {
		1852	(delete $self->{_on_starttls})->($self, undef, $err);
		1853	&_freetls;
		1854	} else {
		1855	&_freetls;
		1856	$self->_error (Errno::EPROTO, 1, $err);
		1857	}
		1858	}
		1859
		1860	# poll the write BIO and send the data if applicable
		1861	# also decode read data if possible
		1862	# this is basiclaly our TLS state machine
		1863	# more efficient implementations are possible with openssl,
		1864	# but not with the buggy and incomplete Net::SSLeay.
1137	sub _dotls {	1865	sub _dotls {
1138	my ($self) = @_;	1866	my ($self) = @_;
1139		1867
1140	my $buf;	1868	my $tmp;
1141		1869
1142	if (length $self->{_tls_wbuf}) {	1870	if (length $self->{_tls_wbuf}) {
1143	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1871	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1144	substr $self->{_tls_wbuf}, 0, $len, "";	1872	substr $self->{_tls_wbuf}, 0, $tmp, "";
1145	}	1873	}
1146	}
1147		1874
		1875	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1876	return $self->_tls_error ($tmp)
		1877	if $tmp != $ERROR_WANT_READ
		1878	&& ($tmp != $ERROR_SYSCALL || $!);
		1879	}
		1880
		1881	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1882	unless (length $tmp) {
		1883	$self->{_on_starttls}
		1884	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1885	&_freetls;
		1886
		1887	if ($self->{on_stoptls}) {
		1888	$self->{on_stoptls}($self);
		1889	return;
		1890	} else {
		1891	# let's treat SSL-eof as we treat normal EOF
		1892	delete $self->{_rw};
		1893	$self->{_eof} = 1;
		1894	}
		1895	}
		1896
		1897	$self->{_tls_rbuf} .= $tmp;
		1898	$self->_drain_rbuf;
		1899	$self->{tls} or return; # tls session might have gone away in callback
		1900	}
		1901
		1902	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1903	return $self->_tls_error ($tmp)
		1904	if $tmp != $ERROR_WANT_READ
		1905	&& ($tmp != $ERROR_SYSCALL || $!);
		1906
1148	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1907	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1149	$self->{wbuf} .= $buf;	1908	$self->{wbuf} .= $tmp;
1150	$self->_drain_wbuf;	1909	$self->_drain_wbuf;
		1910	$self->{tls} or return; # tls session might have gone away in callback
1151	}	1911	}
1152		1912
1153	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1913	$self->{_on_starttls}
1154	if (length $buf) {	1914	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1155	$self->{rbuf} .= $buf;	1915	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1156	$self->_drain_rbuf unless $self->{_in_drain};
1157	} else {
1158	# let's treat SSL-eof as we treat normal EOF
1159	$self->{_eof} = 1;
1160	$self->_shutdown;
1161	return;
1162	}
1163	}
1164
1165	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1166
1167	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1168	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1169	return $self->_error ($!, 1);
1170	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1171	return $self->_error (&Errno::EIO, 1);
1172	}
1173
1174	# all others are fine for our purposes
1175	}
1176	}	1916	}
1177		1917
1178	=item $handle->starttls ($tls[, $tls_ctx])	1918	=item $handle->starttls ($tls[, $tls_ctx])
1179		1919
1180	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1920	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1181	object is created, you can also do that at a later time by calling	1921	object is created, you can also do that at a later time by calling
1182	C<starttls>.	1922	C<starttls>.
1183		1923
		1924	Starting TLS is currently an asynchronous operation - when you push some
		1925	write data and then call C<< ->starttls >> then TLS negotiation will start
		1926	immediately, after which the queued write data is then sent.
		1927
1184	The first argument is the same as the C<tls> constructor argument (either	1928	The first argument is the same as the C<tls> constructor argument (either
1185	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1929	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1186		1930
1187	The second argument is the optional C<Net::SSLeay::CTX> object that is	1931	The second argument is the optional C<AnyEvent::TLS> object that is used
1188	used when AnyEvent::Handle has to create its own TLS connection object.	1932	when AnyEvent::Handle has to create its own TLS connection object, or
		1933	a hash reference with C<< key => value >> pairs that will be used to
		1934	construct a new context.
1189		1935
1190	The TLS connection object will end up in C<< $handle->{tls} >> after this	1936	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1191	call and can be used or changed to your liking. Note that the handshake	1937	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1192	might have already started when this function returns.	1938	changed to your liking. Note that the handshake might have already started
		1939	when this function returns.
1193		1940
		1941	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1942	handshakes on the same stream. It is best to not attempt to use the
		1943	stream after stopping TLS.
		1944
		1945	This method may invoke callbacks (and therefore the handle might be
		1946	destroyed after it returns).
		1947
1194	=cut	1948	=cut
		1949
		1950	our %TLS_CACHE; #TODO not yet documented, should we?
1195		1951
1196	sub starttls {	1952	sub starttls {
1197	my ($self, $ssl, $ctx) = @_;	1953	my ($self, $tls, $ctx) = @_;
1198		1954
1199	$self->stoptls;	1955	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1956	if $self->{tls};
1200		1957
1201	if ($ssl eq "accept") {	1958	$self->{tls} = $tls;
1202	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1959	$self->{tls_ctx} = $ctx if @_ > 2;
1203	Net::SSLeay::set_accept_state ($ssl);	1960
1204	} elsif ($ssl eq "connect") {	1961	return unless $self->{fh};
1205	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1962
1206	Net::SSLeay::set_connect_state ($ssl);	1963	require Net::SSLeay;
		1964
		1965	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		1966	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1967
		1968	$tls = delete $self->{tls};
		1969	$ctx = $self->{tls_ctx};
		1970
		1971	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1972
		1973	if ("HASH" eq ref $ctx) {
		1974	require AnyEvent::TLS;
		1975
		1976	if ($ctx->{cache}) {
		1977	my $key = $ctx+0;
		1978	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1979	} else {
		1980	$ctx = new AnyEvent::TLS %$ctx;
		1981	}
		1982	}
1207	}	1983
1208		1984	$self->{tls_ctx} = $ctx || TLS_CTX ();
1209	$self->{tls} = $ssl;	1985	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1210		1986
1211	# basically, this is deep magic (because SSL_read should have the same issues)	1987	# basically, this is deep magic (because SSL_read should have the same issues)
1212	# but the openssl maintainers basically said: "trust us, it just works".	1988	# but the openssl maintainers basically said: "trust us, it just works".
1213	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1989	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1214	# and mismaintained ssleay-module doesn't even offer them).	1990	# and mismaintained ssleay-module doesn't even offer them).
1215	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1991	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1992	#
		1993	# in short: this is a mess.
		1994	#
		1995	# note that we do not try to keep the length constant between writes as we are required to do.
		1996	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1997	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1998	# have identity issues in that area.
1216	Net::SSLeay::CTX_set_mode ($self->{tls},	1999	# Net::SSLeay::CTX_set_mode ($ssl,
1217	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2000	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1218	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2001	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		2002	Net::SSLeay::CTX_set_mode ($tls, 1|2);
1219		2003
1220	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2004	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1221	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2005	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1222		2006
		2007	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		2008
1223	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	2009	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1224		2010
1225	$self->{filter_w} = sub {	2011	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1226	$_[0]{_tls_wbuf} .= ${$_[1]};	2012	if $self->{on_starttls};
1227	&_dotls;	2013
1228	};	2014	&_dotls; # need to trigger the initial handshake
1229	$self->{filter_r} = sub {	2015	$self->start_read; # make sure we actually do read
1230	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1231	&_dotls;
1232	};
1233	}	2016	}
1234		2017
1235	=item $handle->stoptls	2018	=item $handle->stoptls
1236		2019
1237	Destroys the SSL connection, if any. Partial read or write data will be	2020	Shuts down the SSL connection - this makes a proper EOF handshake by
1238	lost.	2021	sending a close notify to the other side, but since OpenSSL doesn't
		2022	support non-blocking shut downs, it is not guaranteed that you can re-use
		2023	the stream afterwards.
		2024
		2025	This method may invoke callbacks (and therefore the handle might be
		2026	destroyed after it returns).
1239		2027
1240	=cut	2028	=cut
1241		2029
1242	sub stoptls {	2030	sub stoptls {
1243	my ($self) = @_;	2031	my ($self) = @_;
1244		2032
1245	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	2033	if ($self->{tls} && $self->{fh}) {
		2034	Net::SSLeay::shutdown ($self->{tls});
1246		2035
1247	delete $self->{_rbio};	2036	&_dotls;
1248	delete $self->{_wbio};	2037
1249	delete $self->{_tls_wbuf};	2038	# # we don't give a shit. no, we do, but we can't. no...#d#
1250	delete $self->{filter_r};	2039	# # we, we... have to use openssl :/#d#
1251	delete $self->{filter_w};	2040	# &_freetls;#d#
		2041	}
1252	}	2042	}
		2043
		2044	sub _freetls {
		2045	my ($self) = @_;
		2046
		2047	return unless $self->{tls};
		2048
		2049	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2050	if $self->{tls} > 0;
		2051
		2052	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		2053	}
		2054
		2055	=item $handle->resettls
		2056
		2057	This rarely-used method simply resets and TLS state on the handle, usually
		2058	causing data loss.
		2059
		2060	One case where it may be useful is when you want to skip over the data in
		2061	the stream but you are not interested in interpreting it, so data loss is
		2062	no concern.
		2063
		2064	=cut
		2065
		2066	*resettls = \&_freetls;
1253		2067
1254	sub DESTROY {	2068	sub DESTROY {
1255	my $self = shift;	2069	my ($self) = @_;
1256		2070
1257	$self->stoptls;	2071	&_freetls;
		2072
		2073	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		2074
		2075	if ($linger && length $self->{wbuf} && $self->{fh}) {
		2076	my $fh = delete $self->{fh};
		2077	my $wbuf = delete $self->{wbuf};
		2078
		2079	my @linger;
		2080
		2081	push @linger, AE::io $fh, 1, sub {
		2082	my $len = syswrite $fh, $wbuf, length $wbuf;
		2083
		2084	if ($len > 0) {
		2085	substr $wbuf, 0, $len, "";
		2086	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
		2087	@linger = (); # end
		2088	}
		2089	};
		2090	push @linger, AE::timer $linger, 0, sub {
		2091	@linger = ();
		2092	};
		2093	}
1258	}	2094	}
		2095
		2096	=item $handle->destroy
		2097
		2098	Shuts down the handle object as much as possible - this call ensures that
		2099	no further callbacks will be invoked and as many resources as possible
		2100	will be freed. Any method you will call on the handle object after
		2101	destroying it in this way will be silently ignored (and it will return the
		2102	empty list).
		2103
		2104	Normally, you can just "forget" any references to an AnyEvent::Handle
		2105	object and it will simply shut down. This works in fatal error and EOF
		2106	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2107	callback, so when you want to destroy the AnyEvent::Handle object from
		2108	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2109	that case.
		2110
		2111	Destroying the handle object in this way has the advantage that callbacks
		2112	will be removed as well, so if those are the only reference holders (as
		2113	is common), then one doesn't need to do anything special to break any
		2114	reference cycles.
		2115
		2116	The handle might still linger in the background and write out remaining
		2117	data, as specified by the C<linger> option, however.
		2118
		2119	=cut
		2120
		2121	sub destroy {
		2122	my ($self) = @_;
		2123
		2124	$self->DESTROY;
		2125	%$self = ();
		2126	bless $self, "AnyEvent::Handle::destroyed";
		2127	}
		2128
		2129	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2130	#nop
		2131	}
		2132
		2133	=item $handle->destroyed
		2134
		2135	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2136	->destroy >>, true otherwise.
		2137
		2138	Can be useful to decide whether the handle is still valid after some
		2139	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2140	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2141	can destroy the handle, so work can be avoided by checking sometimes:
		2142
		2143	$hdl->starttls ("accept");
		2144	return if $hdl->destroyed;
		2145	$hdl->push_write (...
		2146
		2147	Note that the call to C<push_write> will silently be ignored if the handle
		2148	has been destroyed, so often you can just ignore the possibility of the
		2149	handle being destroyed.
		2150
		2151	=cut
		2152
		2153	sub destroyed { 0 }
		2154	sub AnyEvent::Handle::destroyed::destroyed { 1 }
1259		2155
1260	=item AnyEvent::Handle::TLS_CTX	2156	=item AnyEvent::Handle::TLS_CTX
1261		2157
1262	This function creates and returns the Net::SSLeay::CTX object used by	2158	This function creates and returns the AnyEvent::TLS object used by default
1263	default for TLS mode.	2159	for TLS mode.
1264		2160
1265	The context is created like this:	2161	The context is created by calling L<AnyEvent::TLS> without any arguments.
1266
1267	Net::SSLeay::load_error_strings;
1268	Net::SSLeay::SSLeay_add_ssl_algorithms;
1269	Net::SSLeay::randomize;
1270
1271	my $CTX = Net::SSLeay::CTX_new;
1272
1273	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1274		2162
1275	=cut	2163	=cut
1276		2164
1277	our $TLS_CTX;	2165	our $TLS_CTX;
1278		2166
1279	sub TLS_CTX() {	2167	sub TLS_CTX() {
1280	$TLS_CTX || do {	2168	$TLS_CTX ||= do {
1281	require Net::SSLeay;	2169	require AnyEvent::TLS;
1282		2170
1283	Net::SSLeay::load_error_strings ();	2171	new AnyEvent::TLS
1284	Net::SSLeay::SSLeay_add_ssl_algorithms ();
1285	Net::SSLeay::randomize ();
1286
1287	$TLS_CTX = Net::SSLeay::CTX_new ();
1288
1289	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1290
1291	$TLS_CTX
1292	}	2172	}
1293	}	2173	}
1294		2174
1295	=back	2175	=back
		2176
		2177
		2178	=head1 NONFREQUENTLY ASKED QUESTIONS
		2179
		2180	=over 4
		2181
		2182	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2183	still get further invocations!
		2184
		2185	That's because AnyEvent::Handle keeps a reference to itself when handling
		2186	read or write callbacks.
		2187
		2188	It is only safe to "forget" the reference inside EOF or error callbacks,
		2189	from within all other callbacks, you need to explicitly call the C<<
		2190	->destroy >> method.
		2191
		2192	=item Why is my C<on_eof> callback never called?
		2193
		2194	Probably because your C<on_error> callback is being called instead: When
		2195	you have outstanding requests in your read queue, then an EOF is
		2196	considered an error as you clearly expected some data.
		2197
		2198	To avoid this, make sure you have an empty read queue whenever your handle
		2199	is supposed to be "idle" (i.e. connection closes are O.K.). You cna set
		2200	an C<on_read> handler that simply pushes the first read requests in the
		2201	queue.
		2202
		2203	See also the next question, which explains this in a bit more detail.
		2204
		2205	=item How can I serve requests in a loop?
		2206
		2207	Most protocols consist of some setup phase (authentication for example)
		2208	followed by a request handling phase, where the server waits for requests
		2209	and handles them, in a loop.
		2210
		2211	There are two important variants: The first (traditional, better) variant
		2212	handles requests until the server gets some QUIT command, causing it to
		2213	close the connection first (highly desirable for a busy TCP server). A
		2214	client dropping the connection is an error, which means this variant can
		2215	detect an unexpected detection close.
		2216
		2217	To handle this case, always make sure you have a on-empty read queue, by
		2218	pushing the "read request start" handler on it:
		2219
		2220	# we assume a request starts with a single line
		2221	my @start_request; @start_request = (line => sub {
		2222	my ($hdl, $line) = @_;
		2223
		2224	... handle request
		2225
		2226	# push next request read, possibly from a nested callback
		2227	$hdl->push_read (@start_request);
		2228	});
		2229
		2230	# auth done, now go into request handling loop
		2231	# now push the first @start_request
		2232	$hdl->push_read (@start_request);
		2233
		2234	By always having an outstanding C<push_read>, the handle always expects
		2235	some data and raises the C<EPIPE> error when the connction is dropped
		2236	unexpectedly.
		2237
		2238	The second variant is a protocol where the client can drop the connection
		2239	at any time. For TCP, this means that the server machine may run out of
		2240	sockets easier, and in general, it means you cnanot distinguish a protocl
		2241	failure/client crash from a normal connection close. Nevertheless, these
		2242	kinds of protocols are common (and sometimes even the best solution to the
		2243	problem).
		2244
		2245	Having an outstanding read request at all times is possible if you ignore
		2246	C<EPIPE> errors, but this doesn't help with when the client drops the
		2247	connection during a request, which would still be an error.
		2248
		2249	A better solution is to push the initial request read in an C<on_read>
		2250	callback. This avoids an error, as when the server doesn't expect data
		2251	(i.e. is idly waiting for the next request, an EOF will not raise an
		2252	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2253	and simpler:
		2254
		2255	# auth done, now go into request handling loop
		2256	$hdl->on_read (sub {
		2257	my ($hdl) = @_;
		2258
		2259	# called each time we receive data but the read queue is empty
		2260	# simply start read the request
		2261
		2262	$hdl->push_read (line => sub {
		2263	my ($hdl, $line) = @_;
		2264
		2265	... handle request
		2266
		2267	# do nothing special when the request has been handled, just
		2268	# let the request queue go empty.
		2269	});
		2270	});
		2271
		2272	=item I get different callback invocations in TLS mode/Why can't I pause
		2273	reading?
		2274
		2275	Unlike, say, TCP, TLS connections do not consist of two independent
		2276	communication channels, one for each direction. Or put differently, the
		2277	read and write directions are not independent of each other: you cannot
		2278	write data unless you are also prepared to read, and vice versa.
		2279
		2280	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2281	callback invocations when you are not expecting any read data - the reason
		2282	is that AnyEvent::Handle always reads in TLS mode.
		2283
		2284	During the connection, you have to make sure that you always have a
		2285	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2286	connection (or when you no longer want to use it) you can call the
		2287	C<destroy> method.
		2288
		2289	=item How do I read data until the other side closes the connection?
		2290
		2291	If you just want to read your data into a perl scalar, the easiest way
		2292	to achieve this is by setting an C<on_read> callback that does nothing,
		2293	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2294	will be in C<$_[0]{rbuf}>:
		2295
		2296	$handle->on_read (sub { });
		2297	$handle->on_eof (undef);
		2298	$handle->on_error (sub {
		2299	my $data = delete $_[0]{rbuf};
		2300	});
		2301
		2302	The reason to use C<on_error> is that TCP connections, due to latencies
		2303	and packets loss, might get closed quite violently with an error, when in
		2304	fact all data has been received.
		2305
		2306	It is usually better to use acknowledgements when transferring data,
		2307	to make sure the other side hasn't just died and you got the data
		2308	intact. This is also one reason why so many internet protocols have an
		2309	explicit QUIT command.
		2310
		2311	=item I don't want to destroy the handle too early - how do I wait until
		2312	all data has been written?
		2313
		2314	After writing your last bits of data, set the C<on_drain> callback
		2315	and destroy the handle in there - with the default setting of
		2316	C<low_water_mark> this will be called precisely when all data has been
		2317	written to the socket:
		2318
		2319	$handle->push_write (...);
		2320	$handle->on_drain (sub {
		2321	warn "all data submitted to the kernel\n";
		2322	undef $handle;
		2323	});
		2324
		2325	If you just want to queue some data and then signal EOF to the other side,
		2326	consider using C<< ->push_shutdown >> instead.
		2327
		2328	=item I want to contact a TLS/SSL server, I don't care about security.
		2329
		2330	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2331	connect to it and then create the AnyEvent::Handle with the C<tls>
		2332	parameter:
		2333
		2334	tcp_connect $host, $port, sub {
		2335	my ($fh) = @_;
		2336
		2337	my $handle = new AnyEvent::Handle
		2338	fh => $fh,
		2339	tls => "connect",
		2340	on_error => sub { ... };
		2341
		2342	$handle->push_write (...);
		2343	};
		2344
		2345	=item I want to contact a TLS/SSL server, I do care about security.
		2346
		2347	Then you should additionally enable certificate verification, including
		2348	peername verification, if the protocol you use supports it (see
		2349	L<AnyEvent::TLS>, C<verify_peername>).
		2350
		2351	E.g. for HTTPS:
		2352
		2353	tcp_connect $host, $port, sub {
		2354	my ($fh) = @_;
		2355
		2356	my $handle = new AnyEvent::Handle
		2357	fh => $fh,
		2358	peername => $host,
		2359	tls => "connect",
		2360	tls_ctx => { verify => 1, verify_peername => "https" },
		2361	...
		2362
		2363	Note that you must specify the hostname you connected to (or whatever
		2364	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2365	peername verification will be done.
		2366
		2367	The above will use the system-dependent default set of trusted CA
		2368	certificates. If you want to check against a specific CA, add the
		2369	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2370
		2371	tls_ctx => {
		2372	verify => 1,
		2373	verify_peername => "https",
		2374	ca_file => "my-ca-cert.pem",
		2375	},
		2376
		2377	=item I want to create a TLS/SSL server, how do I do that?
		2378
		2379	Well, you first need to get a server certificate and key. You have
		2380	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2381	self-signed certificate (cheap. check the search engine of your choice,
		2382	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2383	nice program for that purpose).
		2384
		2385	Then create a file with your private key (in PEM format, see
		2386	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2387	file should then look like this:
		2388
		2389	-----BEGIN RSA PRIVATE KEY-----
		2390	...header data
		2391	... lots of base64'y-stuff
		2392	-----END RSA PRIVATE KEY-----
		2393
		2394	-----BEGIN CERTIFICATE-----
		2395	... lots of base64'y-stuff
		2396	-----END CERTIFICATE-----
		2397
		2398	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2399	specify this file as C<cert_file>:
		2400
		2401	tcp_server undef, $port, sub {
		2402	my ($fh) = @_;
		2403
		2404	my $handle = new AnyEvent::Handle
		2405	fh => $fh,
		2406	tls => "accept",
		2407	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2408	...
		2409
		2410	When you have intermediate CA certificates that your clients might not
		2411	know about, just append them to the C<cert_file>.
		2412
		2413	=back
		2414
1296		2415
1297	=head1 SUBCLASSING AnyEvent::Handle	2416	=head1 SUBCLASSING AnyEvent::Handle
1298		2417
1299	In many cases, you might want to subclass AnyEvent::Handle.	2418	In many cases, you might want to subclass AnyEvent::Handle.
1300		2419
…		…
1304	=over 4	2423	=over 4
1305		2424
1306	=item * all constructor arguments become object members.	2425	=item * all constructor arguments become object members.
1307		2426
1308	At least initially, when you pass a C<tls>-argument to the constructor it	2427	At least initially, when you pass a C<tls>-argument to the constructor it
1309	will end up in C<< $handle->{tls} >>. Those members might be changes or	2428	will end up in C<< $handle->{tls} >>. Those members might be changed or
1310	mutated later on (for example C<tls> will hold the TLS connection object).	2429	mutated later on (for example C<tls> will hold the TLS connection object).
1311		2430
1312	=item * other object member names are prefixed with an C<_>.	2431	=item * other object member names are prefixed with an C<_>.
1313		2432
1314	All object members not explicitly documented (internal use) are prefixed	2433	All object members not explicitly documented (internal use) are prefixed
…		…
1317		2436
1318	=item * all members not documented here and not prefixed with an underscore	2437	=item * all members not documented here and not prefixed with an underscore
1319	are free to use in subclasses.	2438	are free to use in subclasses.
1320		2439
1321	Of course, new versions of AnyEvent::Handle may introduce more "public"	2440	Of course, new versions of AnyEvent::Handle may introduce more "public"
1322	member variables, but thats just life, at least it is documented.	2441	member variables, but that's just life. At least it is documented.
1323		2442
1324	=back	2443	=back
1325		2444
1326	=head1 AUTHOR	2445	=head1 AUTHOR
1327		2446

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