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Revision 1.31 by root, Sun May 25 00:08:49 2008 UTC vs.
Revision 1.240 by root, Tue Dec 17 16:43:15 2013 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict;
5
6	use AnyEvent ();
7	use AnyEvent::Util ();
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 = '0.04';
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	AE::log error => $msg;
		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	say "got line <$line>";
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
78	=item on_eof => $cb->($self)	99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
79		100
80	Set the callback to be called on EOF.	101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
81		104
82	While not mandatory, it is highly recommended to set an eof callback,	105	You have to specify either this parameter, or C<fh>, above.
83	otherwise you might end up with a closed socket while you are still
84	waiting for data.
85		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
86	=item on_error => $cb->($self)	116	=item on_prepare => $cb->($handle)
87		117
		118	This (rarely used) callback is called before a new connection is
		119	attempted, but after the file handle has been created (you can access that
		120	file handle via C<< $handle->{fh} >>). It could be used to prepare the
		121	file handle with parameters required for the actual connect (as opposed to
		122	settings that can be changed when the connection is already established).
		123
		124	The return value of this callback should be the connect timeout value in
		125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
		126	default timeout is to be used).
		127
		128	=item on_connect => $cb->($handle, $host, $port, $retry->())
		129
		130	This callback is called when a connection has been successfully established.
		131
		132	The peer's numeric host and port (the socket peername) are passed as
		133	parameters, together with a retry callback. At the time it is called the
		134	read and write queues, EOF status, TLS status and similar properties of
		135	the handle will have been reset.
		136
		137	It is not allowed to use the read or write queues while the handle object
		138	is connecting.
		139
		140	If, for some reason, the handle is not acceptable, calling C<$retry> will
		141	continue with the next connection target (in case of multi-homed hosts or
		142	SRV records there can be multiple connection endpoints). The C<$retry>
		143	callback can be invoked after the connect callback returns, i.e. one can
		144	start a handshake and then decide to retry with the next host if the
		145	handshake fails.
		146
		147	In most cases, you should ignore the C<$retry> parameter.
		148
		149	=item on_connect_error => $cb->($handle, $message)
		150
		151	This callback is called when the connection could not be
		152	established. C<$!> will contain the relevant error code, and C<$message> a
		153	message describing it (usually the same as C<"$!">).
		154
		155	If this callback isn't specified, then C<on_error> will be called with a
		156	fatal error instead.
		157
		158	=back
		159
		160	=item on_error => $cb->($handle, $fatal, $message)
		161
88	This is the fatal error callback, that is called when, well, a fatal error	162	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	163	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	164	connect, or a read error.
91		165
92	The object will not be in a usable state when this callback has been	166	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	167	fatal errors the handle object will be destroyed (by a call to C<< ->
		168	destroy >>) after invoking the error callback (which means you are free to
		169	examine the handle object). Examples of fatal errors are an EOF condition
		170	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		171	cases where the other side can close the connection at will, it is
		172	often easiest to not report C<EPIPE> errors in this callback.
94		173
		174	AnyEvent::Handle tries to find an appropriate error code for you to check
		175	against, but in some cases (TLS errors), this does not work well.
		176
		177	If you report the error to the user, it is recommended to always output
		178	the C<$message> argument in human-readable error messages (you don't need
		179	to report C<"$!"> if you report C<$message>).
		180
		181	If you want to react programmatically to the error, then looking at C<$!>
		182	and comparing it against some of the documented C<Errno> values is usually
		183	better than looking at the C<$message>.
		184
		185	Non-fatal errors can be retried by returning, but it is recommended
		186	to simply ignore this parameter and instead abondon the handle object
		187	when this callback is invoked. Examples of non-fatal errors are timeouts
		188	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		189
95	On callback entrance, the value of C<$!> contains the operating system	190	On entry to the callback, the value of C<$!> contains the operating
96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).	191	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		192	C<EPROTO>).
97		193
98	While not mandatory, it is I<highly> recommended to set this callback, as	194	While not mandatory, it is I<highly> recommended to set this callback, as
99	you will not be notified of errors otherwise. The default simply calls	195	you will not be notified of errors otherwise. The default just calls
100	die.	196	C<croak>.
101		197
102	=item on_read => $cb->($self)	198	=item on_read => $cb->($handle)
103		199
104	This sets the default read callback, which is called when data arrives	200	This sets the default read callback, which is called when data arrives
105	and no read request is in the queue.	201	and no read request is in the queue (unlike read queue callbacks, this
		202	callback will only be called when at least one octet of data is in the
		203	read buffer).
106		204
107	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	205	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
108	method or access the C<$self->{rbuf}> member directly.	206	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		207	must not enlarge or modify the read buffer, you can only remove data at
		208	the beginning from it.
109		209
		210	You can also call C<< ->push_read (...) >> or any other function that
		211	modifies the read queue. Or do both. Or ...
		212
110	When an EOF condition is detected then AnyEvent::Handle will first try to	213	When an EOF condition is detected, AnyEvent::Handle will first try to
111	feed all the remaining data to the queued callbacks and C<on_read> before	214	feed all the remaining data to the queued callbacks and C<on_read> before
112	calling the C<on_eof> callback. If no progress can be made, then a fatal	215	calling the C<on_eof> callback. If no progress can be made, then a fatal
113	error will be raised (with C<$!> set to C<EPIPE>).	216	error will be raised (with C<$!> set to C<EPIPE>).
114		217
		218	Note that, unlike requests in the read queue, an C<on_read> callback
		219	doesn't mean you I<require> some data: if there is an EOF and there
		220	are outstanding read requests then an error will be flagged. With an
		221	C<on_read> callback, the C<on_eof> callback will be invoked.
		222
		223	=item on_eof => $cb->($handle)
		224
		225	Set the callback to be called when an end-of-file condition is detected,
		226	i.e. in the case of a socket, when the other side has closed the
		227	connection cleanly, and there are no outstanding read requests in the
		228	queue (if there are read requests, then an EOF counts as an unexpected
		229	connection close and will be flagged as an error).
		230
		231	For sockets, this just means that the other side has stopped sending data,
		232	you can still try to write data, and, in fact, one can return from the EOF
		233	callback and continue writing data, as only the read part has been shut
		234	down.
		235
		236	If an EOF condition has been detected but no C<on_eof> callback has been
		237	set, then a fatal error will be raised with C<$!> set to <0>.
		238
115	=item on_drain => $cb->()	239	=item on_drain => $cb->($handle)
116		240
117	This sets the callback that is called when the write buffer becomes empty	241	This sets the callback that is called once when the write buffer becomes
118	(or when the callback is set and the buffer is empty already).	242	empty (and immediately when the handle object is created).
119		243
120	To append to the write buffer, use the C<< ->push_write >> method.	244	To append to the write buffer, use the C<< ->push_write >> method.
		245
		246	This callback is useful when you don't want to put all of your write data
		247	into the queue at once, for example, when you want to write the contents
		248	of some file to the socket you might not want to read the whole file into
		249	memory and push it into the queue, but instead only read more data from
		250	the file when the write queue becomes empty.
		251
		252	=item timeout => $fractional_seconds
		253
		254	=item rtimeout => $fractional_seconds
		255
		256	=item wtimeout => $fractional_seconds
		257
		258	If non-zero, then these enables an "inactivity" timeout: whenever this
		259	many seconds pass without a successful read or write on the underlying
		260	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
		261	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		262	error will be raised).
		263
		264	There are three variants of the timeouts that work independently of each
		265	other, for both read and write (triggered when nothing was read I<OR>
		266	written), just read (triggered when nothing was read), and just write:
		267	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		268	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		269	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		270
		271	Note that timeout processing is active even when you do not have any
		272	outstanding read or write requests: If you plan to keep the connection
		273	idle then you should disable the timeout temporarily or ignore the
		274	timeout in the corresponding C<on_timeout> callback, in which case
		275	AnyEvent::Handle will simply restart the timeout.
		276
		277	Zero (the default) disables the corresponding timeout.
		278
		279	=item on_timeout => $cb->($handle)
		280
		281	=item on_rtimeout => $cb->($handle)
		282
		283	=item on_wtimeout => $cb->($handle)
		284
		285	Called whenever the inactivity timeout passes. If you return from this
		286	callback, then the timeout will be reset as if some activity had happened,
		287	so this condition is not fatal in any way.
121		288
122	=item rbuf_max => <bytes>	289	=item rbuf_max => <bytes>
123		290
124	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	291	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
125	when the read buffer ever (strictly) exceeds this size. This is useful to	292	when the read buffer ever (strictly) exceeds this size. This is useful to
126	avoid denial-of-service attacks.	293	avoid some forms of denial-of-service attacks.
127		294
128	For example, a server accepting connections from untrusted sources should	295	For example, a server accepting connections from untrusted sources should
129	be configured to accept only so-and-so much data that it cannot act on	296	be configured to accept only so-and-so much data that it cannot act on
130	(for example, when expecting a line, an attacker could send an unlimited	297	(for example, when expecting a line, an attacker could send an unlimited
131	amount of data without a callback ever being called as long as the line	298	amount of data without a callback ever being called as long as the line
132	isn't finished).	299	isn't finished).
133		300
		301	=item wbuf_max => <bytes>
		302
		303	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		304	when the write buffer ever (strictly) exceeds this size. This is useful to
		305	avoid some forms of denial-of-service attacks.
		306
		307	Although the units of this parameter is bytes, this is the I<raw> number
		308	of bytes not yet accepted by the kernel. This can make a difference when
		309	you e.g. use TLS, as TLS typically makes your write data larger (but it
		310	can also make it smaller due to compression).
		311
		312	As an example of when this limit is useful, take a chat server that sends
		313	chat messages to a client. If the client does not read those in a timely
		314	manner then the send buffer in the server would grow unbounded.
		315
		316	=item autocork => <boolean>
		317
		318	When disabled (the default), C<push_write> will try to immediately
		319	write the data to the handle if possible. This avoids having to register
		320	a write watcher and wait for the next event loop iteration, but can
		321	be inefficient if you write multiple small chunks (on the wire, this
		322	disadvantage is usually avoided by your kernel's nagle algorithm, see
		323	C<no_delay>, but this option can save costly syscalls).
		324
		325	When enabled, writes will always be queued till the next event loop
		326	iteration. This is efficient when you do many small writes per iteration,
		327	but less efficient when you do a single write only per iteration (or when
		328	the write buffer often is full). It also increases write latency.
		329
		330	=item no_delay => <boolean>
		331
		332	When doing small writes on sockets, your operating system kernel might
		333	wait a bit for more data before actually sending it out. This is called
		334	the Nagle algorithm, and usually it is beneficial.
		335
		336	In some situations you want as low a delay as possible, which can be
		337	accomplishd by setting this option to a true value.
		338
		339	The default is your operating system's default behaviour (most likely
		340	enabled). This option explicitly enables or disables it, if possible.
		341
		342	=item keepalive => <boolean>
		343
		344	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		345	normally, TCP connections have no time-out once established, so TCP
		346	connections, once established, can stay alive forever even when the other
		347	side has long gone. TCP keepalives are a cheap way to take down long-lived
		348	TCP connections when the other side becomes unreachable. While the default
		349	is OS-dependent, TCP keepalives usually kick in after around two hours,
		350	and, if the other side doesn't reply, take down the TCP connection some 10
		351	to 15 minutes later.
		352
		353	It is harmless to specify this option for file handles that do not support
		354	keepalives, and enabling it on connections that are potentially long-lived
		355	is usually a good idea.
		356
		357	=item oobinline => <boolean>
		358
		359	BSD majorly fucked up the implementation of TCP urgent data. The result
		360	is that almost no OS implements TCP according to the specs, and every OS
		361	implements it slightly differently.
		362
		363	If you want to handle TCP urgent data, then setting this flag (the default
		364	is enabled) gives you the most portable way of getting urgent data, by
		365	putting it into the stream.
		366
		367	Since BSD emulation of OOB data on top of TCP's urgent data can have
		368	security implications, AnyEvent::Handle sets this flag automatically
		369	unless explicitly specified. Note that setting this flag after
		370	establishing a connection I<may> be a bit too late (data loss could
		371	already have occured on BSD systems), but at least it will protect you
		372	from most attacks.
		373
134	=item read_size => <bytes>	374	=item read_size => <bytes>
135		375
136	The default read block size (the amount of bytes this module will try to read	376	The initial read block size, the number of bytes this module will try
137	on each [loop iteration). Default: C<4096>.	377	to read during each loop iteration. Each handle object will consume
		378	at least this amount of memory for the read buffer as well, so when
		379	handling many connections watch out for memory requirements). See also
		380	C<max_read_size>. Default: C<2048>.
		381
		382	=item max_read_size => <bytes>
		383
		384	The maximum read buffer size used by the dynamic adjustment
		385	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		386	one go it will double C<read_size> up to the maximum given by this
		387	option. Default: C<131072> or C<read_size>, whichever is higher.
138		388
139	=item low_water_mark => <bytes>	389	=item low_water_mark => <bytes>
140		390
141	Sets the amount of bytes (default: C<0>) that make up an "empty" write	391	Sets the number of bytes (default: C<0>) that make up an "empty" write
142	buffer: If the write reaches this size or gets even samller it is	392	buffer: If the buffer reaches this size or gets even samller it is
143	considered empty.	393	considered empty.
144		394
		395	Sometimes it can be beneficial (for performance reasons) to add data to
		396	the write buffer before it is fully drained, but this is a rare case, as
		397	the operating system kernel usually buffers data as well, so the default
		398	is good in almost all cases.
		399
		400	=item linger => <seconds>
		401
		402	If this is non-zero (default: C<3600>), the destructor of the
		403	AnyEvent::Handle object will check whether there is still outstanding
		404	write data and will install a watcher that will write this data to the
		405	socket. No errors will be reported (this mostly matches how the operating
		406	system treats outstanding data at socket close time).
		407
		408	This will not work for partial TLS data that could not be encoded
		409	yet. This data will be lost. Calling the C<stoptls> method in time might
		410	help.
		411
		412	=item peername => $string
		413
		414	A string used to identify the remote site - usually the DNS hostname
		415	(I<not> IDN!) used to create the connection, rarely the IP address.
		416
		417	Apart from being useful in error messages, this string is also used in TLS
		418	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		419	verification will be skipped when C<peername> is not specified or is
		420	C<undef>.
		421
145	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	422	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
146		423
147	When this parameter is given, it enables TLS (SSL) mode, that means it	424	When this parameter is given, it enables TLS (SSL) mode, that means
148	will start making tls handshake and will transparently encrypt/decrypt	425	AnyEvent will start a TLS handshake as soon as the connection has been
149	data.	426	established and will transparently encrypt/decrypt data afterwards.
		427
		428	All TLS protocol errors will be signalled as C<EPROTO>, with an
		429	appropriate error message.
150		430
151	TLS mode requires Net::SSLeay to be installed (it will be loaded	431	TLS mode requires Net::SSLeay to be installed (it will be loaded
152	automatically when you try to create a TLS handle).	432	automatically when you try to create a TLS handle): this module doesn't
		433	have a dependency on that module, so if your module requires it, you have
		434	to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
		435	old, you get an C<EPROTO> error.
153		436
154	For the TLS server side, use C<accept>, and for the TLS client side of a	437	Unlike TCP, TLS has a server and client side: for the TLS server side, use
155	connection, use C<connect> mode.	438	C<accept>, and for the TLS client side of a connection, use C<connect>
		439	mode.
156		440
157	You can also provide your own TLS connection object, but you have	441	You can also provide your own TLS connection object, but you have
158	to make sure that you call either C<Net::SSLeay::set_connect_state>	442	to make sure that you call either C<Net::SSLeay::set_connect_state>
159	or C<Net::SSLeay::set_accept_state> on it before you pass it to	443	or C<Net::SSLeay::set_accept_state> on it before you pass it to
160	AnyEvent::Handle.	444	AnyEvent::Handle. Also, this module will take ownership of this connection
		445	object.
161		446
		447	At some future point, AnyEvent::Handle might switch to another TLS
		448	implementation, then the option to use your own session object will go
		449	away.
		450
		451	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		452	passing in the wrong integer will lead to certain crash. This most often
		453	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		454	segmentation fault.
		455
162	See the C<starttls> method if you need to start TLs negotiation later.	456	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
163		457
164	=item tls_ctx => $ssl_ctx	458	=item tls_ctx => $anyevent_tls
165		459
166	Use the given Net::SSLeay::CTX object to create the new TLS connection	460	Use the given C<AnyEvent::TLS> object to create the new TLS connection
167	(unless a connection object was specified directly). If this parameter is	461	(unless a connection object was specified directly). If this
168	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	462	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		463	C<AnyEvent::Handle::TLS_CTX>.
		464
		465	Instead of an object, you can also specify a hash reference with C<< key
		466	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		467	new TLS context object.
		468
		469	=item on_starttls => $cb->($handle, $success[, $error_message])
		470
		471	This callback will be invoked when the TLS/SSL handshake has finished. If
		472	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		473	(C<on_stoptls> will not be called in this case).
		474
		475	The session in C<< $handle->{tls} >> can still be examined in this
		476	callback, even when the handshake was not successful.
		477
		478	TLS handshake failures will not cause C<on_error> to be invoked when this
		479	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		480
		481	Without this callback, handshake failures lead to C<on_error> being
		482	called as usual.
		483
		484	Note that you cannot just call C<starttls> again in this callback. If you
		485	need to do that, start an zero-second timer instead whose callback can
		486	then call C<< ->starttls >> again.
		487
		488	=item on_stoptls => $cb->($handle)
		489
		490	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		491	set, then it will be invoked after freeing the TLS session. If it is not,
		492	then a TLS shutdown condition will be treated like a normal EOF condition
		493	on the handle.
		494
		495	The session in C<< $handle->{tls} >> can still be examined in this
		496	callback.
		497
		498	This callback will only be called on TLS shutdowns, not when the
		499	underlying handle signals EOF.
		500
		501	=item json => L<JSON>, L<JSON::PP> or L<JSON::XS> object
		502
		503	This is the json coder object used by the C<json> read and write types.
		504
		505	If you don't supply it, then AnyEvent::Handle will create and use a
		506	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		507	texts.
		508
		509	=item cbor => L<CBOR::XS> object
		510
		511	This is the cbor coder object used by the C<cbor> read and write types.
		512
		513	If you don't supply it, then AnyEvent::Handle will create and use a
		514	suitable one (on demand), which will write CBOR without using extensions,
		515	if possible. texts.
		516
		517	Note that you are responsible to depend on the L<CBOR::XS> module if you
		518	want to use this functionality, as AnyEvent does not have a dependency on
		519	it itself.
169		520
170	=back	521	=back
171		522
172	=cut	523	=cut
173		524
174	sub new {	525	sub new {
175	my $class = shift;	526	my $class = shift;
176
177	my $self = bless { @_ }, $class;	527	my $self = bless { @_ }, $class;
178		528
179	$self->{fh} or Carp::croak "mandatory argument fh is missing";	529	if ($self->{fh}) {
		530	$self->_start;
		531	return unless $self->{fh}; # could be gone by now
		532
		533	} elsif ($self->{connect}) {
		534	require AnyEvent::Socket;
		535
		536	$self->{peername} = $self->{connect}[0]
		537	unless exists $self->{peername};
		538
		539	$self->{_skip_drain_rbuf} = 1;
		540
		541	{
		542	Scalar::Util::weaken (my $self = $self);
		543
		544	$self->{_connect} =
		545	AnyEvent::Socket::tcp_connect (
		546	$self->{connect}[0],
		547	$self->{connect}[1],
		548	sub {
		549	my ($fh, $host, $port, $retry) = @_;
		550
		551	delete $self->{_connect}; # no longer needed
		552
		553	if ($fh) {
		554	$self->{fh} = $fh;
		555
		556	delete $self->{_skip_drain_rbuf};
		557	$self->_start;
		558
		559	$self->{on_connect}
		560	and $self->{on_connect}($self, $host, $port, sub {
		561	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		562	$self->{_skip_drain_rbuf} = 1;
		563	&$retry;
		564	});
		565
		566	} else {
		567	if ($self->{on_connect_error}) {
		568	$self->{on_connect_error}($self, "$!");
		569	$self->destroy if $self;
		570	} else {
		571	$self->_error ($!, 1);
		572	}
		573	}
		574	},
		575	sub {
		576	local $self->{fh} = $_[0];
		577
		578	$self->{on_prepare}
		579	? $self->{on_prepare}->($self)
		580	: ()
		581	}
		582	);
		583	}
		584
		585	} else {
		586	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		587	}
		588
		589	$self
		590	}
		591
		592	sub _start {
		593	my ($self) = @_;
		594
		595	# too many clueless people try to use udp and similar sockets
		596	# with AnyEvent::Handle, do them a favour.
		597	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		598	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		599	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
180		600
181	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	601	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
182		602
183	if ($self->{tls}) {	603	$self->{_activity} =
184	require Net::SSLeay;	604	$self->{_ractivity} =
		605	$self->{_wactivity} = AE::now;
		606
		607	$self->{read_size} ||= 2048;
		608	$self->{max_read_size} = $self->{read_size}
		609	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		610
		611	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		612	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		613	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		614
		615	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		616	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		617
		618	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		619
185	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	620	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
186	}	621	if $self->{tls};
187		622
188	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
189	$self->on_error (delete $self->{on_error}) if $self->{on_error};
190	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	623	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
191	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
192		624
193	$self->start_read;	625	$self->start_read
		626	if $self->{on_read} || @{ $self->{_queue} };
194		627
195	$self	628	$self->_drain_wbuf;
196	}	629	}
197		630
198	sub _shutdown {
199	my ($self) = @_;
200
201	delete $self->{rw};
202	delete $self->{ww};
203	delete $self->{fh};
204	}
205
206	sub error {	631	sub _error {
207	my ($self) = @_;	632	my ($self, $errno, $fatal, $message) = @_;
208		633
209	{	634	$! = $errno;
210	local $!;	635	$message ||= "$!";
211	$self->_shutdown;
212	}
213		636
214	if ($self->{on_error}) {	637	if ($self->{on_error}) {
215	$self->{on_error}($self);	638	$self->{on_error}($self, $fatal, $message);
216	} else {	639	$self->destroy if $fatal;
		640	} elsif ($self->{fh} || $self->{connect}) {
		641	$self->destroy;
217	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	642	Carp::croak "AnyEvent::Handle uncaught error: $message";
218	}	643	}
219	}	644	}
220		645
221	=item $fh = $handle->fh	646	=item $fh = $handle->fh
222		647
223	This method returns the file handle of the L<AnyEvent::Handle> object.	648	This method returns the file handle used to create the L<AnyEvent::Handle> object.
224		649
225	=cut	650	=cut
226		651
227	sub fh { $_[0]->{fh} }	652	sub fh { $_[0]{fh} }
228		653
229	=item $handle->on_error ($cb)	654	=item $handle->on_error ($cb)
230		655
231	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	656	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
232		657
…		…
244		669
245	sub on_eof {	670	sub on_eof {
246	$_[0]{on_eof} = $_[1];	671	$_[0]{on_eof} = $_[1];
247	}	672	}
248		673
		674	=item $handle->on_timeout ($cb)
		675
		676	=item $handle->on_rtimeout ($cb)
		677
		678	=item $handle->on_wtimeout ($cb)
		679
		680	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		681	callback, or disables the callback (but not the timeout) if C<$cb> =
		682	C<undef>. See the C<timeout> constructor argument and method.
		683
		684	=cut
		685
		686	# see below
		687
		688	=item $handle->autocork ($boolean)
		689
		690	Enables or disables the current autocork behaviour (see C<autocork>
		691	constructor argument). Changes will only take effect on the next write.
		692
		693	=cut
		694
		695	sub autocork {
		696	$_[0]{autocork} = $_[1];
		697	}
		698
		699	=item $handle->no_delay ($boolean)
		700
		701	Enables or disables the C<no_delay> setting (see constructor argument of
		702	the same name for details).
		703
		704	=cut
		705
		706	sub no_delay {
		707	$_[0]{no_delay} = $_[1];
		708
		709	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		710	if $_[0]{fh};
		711	}
		712
		713	=item $handle->keepalive ($boolean)
		714
		715	Enables or disables the C<keepalive> setting (see constructor argument of
		716	the same name for details).
		717
		718	=cut
		719
		720	sub keepalive {
		721	$_[0]{keepalive} = $_[1];
		722
		723	eval {
		724	local $SIG{__DIE__};
		725	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		726	if $_[0]{fh};
		727	};
		728	}
		729
		730	=item $handle->oobinline ($boolean)
		731
		732	Enables or disables the C<oobinline> setting (see constructor argument of
		733	the same name for details).
		734
		735	=cut
		736
		737	sub oobinline {
		738	$_[0]{oobinline} = $_[1];
		739
		740	eval {
		741	local $SIG{__DIE__};
		742	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		743	if $_[0]{fh};
		744	};
		745	}
		746
		747	=item $handle->keepalive ($boolean)
		748
		749	Enables or disables the C<keepalive> setting (see constructor argument of
		750	the same name for details).
		751
		752	=cut
		753
		754	sub keepalive {
		755	$_[0]{keepalive} = $_[1];
		756
		757	eval {
		758	local $SIG{__DIE__};
		759	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		760	if $_[0]{fh};
		761	};
		762	}
		763
		764	=item $handle->on_starttls ($cb)
		765
		766	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		767
		768	=cut
		769
		770	sub on_starttls {
		771	$_[0]{on_starttls} = $_[1];
		772	}
		773
		774	=item $handle->on_stoptls ($cb)
		775
		776	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		777
		778	=cut
		779
		780	sub on_stoptls {
		781	$_[0]{on_stoptls} = $_[1];
		782	}
		783
		784	=item $handle->rbuf_max ($max_octets)
		785
		786	Configures the C<rbuf_max> setting (C<undef> disables it).
		787
		788	=item $handle->wbuf_max ($max_octets)
		789
		790	Configures the C<wbuf_max> setting (C<undef> disables it).
		791
		792	=cut
		793
		794	sub rbuf_max {
		795	$_[0]{rbuf_max} = $_[1];
		796	}
		797
		798	sub wbuf_max {
		799	$_[0]{wbuf_max} = $_[1];
		800	}
		801
		802	#############################################################################
		803
		804	=item $handle->timeout ($seconds)
		805
		806	=item $handle->rtimeout ($seconds)
		807
		808	=item $handle->wtimeout ($seconds)
		809
		810	Configures (or disables) the inactivity timeout.
		811
		812	The timeout will be checked instantly, so this method might destroy the
		813	handle before it returns.
		814
		815	=item $handle->timeout_reset
		816
		817	=item $handle->rtimeout_reset
		818
		819	=item $handle->wtimeout_reset
		820
		821	Reset the activity timeout, as if data was received or sent.
		822
		823	These methods are cheap to call.
		824
		825	=cut
		826
		827	for my $dir ("", "r", "w") {
		828	my $timeout = "${dir}timeout";
		829	my $tw = "_${dir}tw";
		830	my $on_timeout = "on_${dir}timeout";
		831	my $activity = "_${dir}activity";
		832	my $cb;
		833
		834	*$on_timeout = sub {
		835	$_[0]{$on_timeout} = $_[1];
		836	};
		837
		838	*$timeout = sub {
		839	my ($self, $new_value) = @_;
		840
		841	$new_value >= 0
		842	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		843
		844	$self->{$timeout} = $new_value;
		845	delete $self->{$tw}; &$cb;
		846	};
		847
		848	*{"${dir}timeout_reset"} = sub {
		849	$_[0]{$activity} = AE::now;
		850	};
		851
		852	# main workhorse:
		853	# reset the timeout watcher, as neccessary
		854	# also check for time-outs
		855	$cb = sub {
		856	my ($self) = @_;
		857
		858	if ($self->{$timeout} && $self->{fh}) {
		859	my $NOW = AE::now;
		860
		861	# when would the timeout trigger?
		862	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		863
		864	# now or in the past already?
		865	if ($after <= 0) {
		866	$self->{$activity} = $NOW;
		867
		868	if ($self->{$on_timeout}) {
		869	$self->{$on_timeout}($self);
		870	} else {
		871	$self->_error (Errno::ETIMEDOUT);
		872	}
		873
		874	# callback could have changed timeout value, optimise
		875	return unless $self->{$timeout};
		876
		877	# calculate new after
		878	$after = $self->{$timeout};
		879	}
		880
		881	Scalar::Util::weaken $self;
		882	return unless $self; # ->error could have destroyed $self
		883
		884	$self->{$tw} ||= AE::timer $after, 0, sub {
		885	delete $self->{$tw};
		886	$cb->($self);
		887	};
		888	} else {
		889	delete $self->{$tw};
		890	}
		891	}
		892	}
		893
249	#############################################################################	894	#############################################################################
250		895
251	=back	896	=back
252		897
253	=head2 WRITE QUEUE	898	=head2 WRITE QUEUE
…		…
257		902
258	The write queue is very simple: you can add data to its end, and	903	The write queue is very simple: you can add data to its end, and
259	AnyEvent::Handle will automatically try to get rid of it for you.	904	AnyEvent::Handle will automatically try to get rid of it for you.
260		905
261	When data could be written and the write buffer is shorter then the low	906	When data could be written and the write buffer is shorter then the low
262	water mark, the C<on_drain> callback will be invoked.	907	water mark, the C<on_drain> callback will be invoked once.
263		908
264	=over 4	909	=over 4
265		910
266	=item $handle->on_drain ($cb)	911	=item $handle->on_drain ($cb)
267		912
268	Sets the C<on_drain> callback or clears it (see the description of	913	Sets the C<on_drain> callback or clears it (see the description of
269	C<on_drain> in the constructor).	914	C<on_drain> in the constructor).
270		915
		916	This method may invoke callbacks (and therefore the handle might be
		917	destroyed after it returns).
		918
271	=cut	919	=cut
272		920
273	sub on_drain {	921	sub on_drain {
274	my ($self, $cb) = @_;	922	my ($self, $cb) = @_;
275		923
276	$self->{on_drain} = $cb;	924	$self->{on_drain} = $cb;
277		925
278	$cb->($self)	926	$cb->($self)
279	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	927	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
280	}	928	}
281		929
282	=item $handle->push_write ($data)	930	=item $handle->push_write ($data)
283		931
284	Queues the given scalar to be written. You can push as much data as you	932	Queues the given scalar to be written. You can push as much data as
285	want (only limited by the available memory), as C<AnyEvent::Handle>	933	you want (only limited by the available memory and C<wbuf_max>), as
286	buffers it independently of the kernel.	934	C<AnyEvent::Handle> buffers it independently of the kernel.
		935
		936	This method may invoke callbacks (and therefore the handle might be
		937	destroyed after it returns).
287		938
288	=cut	939	=cut
289		940
290	sub _drain_wbuf {	941	sub _drain_wbuf {
291	my ($self) = @_;	942	my ($self) = @_;
292		943
293	if (!$self->{ww} && length $self->{wbuf}) {	944	if (!$self->{_ww} && length $self->{wbuf}) {
		945
294	Scalar::Util::weaken $self;	946	Scalar::Util::weaken $self;
		947
295	my $cb = sub {	948	my $cb = sub {
296	my $len = syswrite $self->{fh}, $self->{wbuf};	949	my $len = syswrite $self->{fh}, $self->{wbuf};
297		950
298	if ($len >= 0) {	951	if (defined $len) {
299	substr $self->{wbuf}, 0, $len, "";	952	substr $self->{wbuf}, 0, $len, "";
300		953
		954	$self->{_activity} = $self->{_wactivity} = AE::now;
		955
301	$self->{on_drain}($self)	956	$self->{on_drain}($self)
302	if $self->{low_water_mark} >= length $self->{wbuf}	957	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
303	&& $self->{on_drain};	958	&& $self->{on_drain};
304		959
305	delete $self->{ww} unless length $self->{wbuf};	960	delete $self->{_ww} unless length $self->{wbuf};
306	} elsif ($! != EAGAIN && $! != EINTR) {	961	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
307	$self->error;	962	$self->_error ($!, 1);
308	}	963	}
309	};	964	};
310		965
311	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	966	# try to write data immediately
		967	$cb->() unless $self->{autocork};
312		968
313	$cb->($self);	969	# if still data left in wbuf, we need to poll
		970	$self->{_ww} = AE::io $self->{fh}, 1, $cb
		971	if length $self->{wbuf};
		972
		973	if (
		974	defined $self->{wbuf_max}
		975	&& $self->{wbuf_max} < length $self->{wbuf}
		976	) {
		977	$self->_error (Errno::ENOSPC, 1), return;
		978	}
314	};	979	};
315	}	980	}
316		981
317	our %WH;	982	our %WH;
318		983
		984	# deprecated
319	sub register_write_type($$) {	985	sub register_write_type($$) {
320	$WH{$_[0]} = $_[1];	986	$WH{$_[0]} = $_[1];
321	}	987	}
322		988
323	sub push_write {	989	sub push_write {
324	my $self = shift;	990	my $self = shift;
325		991
326	if (@_ > 1) {	992	if (@_ > 1) {
327	my $type = shift;	993	my $type = shift;
328		994
		995	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
329	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	996	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
330	->($self, @_);	997	->($self, @_);
331	}	998	}
332		999
		1000	# we downgrade here to avoid hard-to-track-down bugs,
		1001	# and diagnose the problem earlier and better.
		1002
333	if ($self->{filter_w}) {	1003	if ($self->{tls}) {
334	$self->{filter_w}->($self, \$_[0]);	1004	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		1005	&_dotls ($self) if $self->{fh};
335	} else {	1006	} else {
336	$self->{wbuf} .= $_[0];	1007	utf8::downgrade $self->{wbuf} .= $_[0];
337	$self->_drain_wbuf;	1008	$self->_drain_wbuf if $self->{fh};
338	}	1009	}
339	}	1010	}
340		1011
341	=item $handle->push_write (type => @args)	1012	=item $handle->push_write (type => @args)
342		1013
343	=item $handle->unshift_write (type => @args)
344
345	Instead of formatting your data yourself, you can also let this module do	1014	Instead of formatting your data yourself, you can also let this module
346	the job by specifying a type and type-specific arguments.	1015	do the job by specifying a type and type-specific arguments. You
		1016	can also specify the (fully qualified) name of a package, in which
		1017	case AnyEvent tries to load the package and then expects to find the
		1018	C<anyevent_write_type> function inside (see "custom write types", below).
347		1019
348	Predefined types are (if you have ideas for additional types, feel free to	1020	Predefined types are (if you have ideas for additional types, feel free to
349	drop by and tell us):	1021	drop by and tell us):
350		1022
351	=over 4	1023	=over 4
…		…
353	=item netstring => $string	1025	=item netstring => $string
354		1026
355	Formats the given value as netstring	1027	Formats the given value as netstring
356	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	1028	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
357		1029
358	=back
359
360	=cut	1030	=cut
361		1031
362	register_write_type netstring => sub {	1032	register_write_type netstring => sub {
363	my ($self, $string) = @_;	1033	my ($self, $string) = @_;
364		1034
365	sprintf "%d:%s,", (length $string), $string	1035	(length $string) . ":$string,"
366	};	1036	};
367		1037
368	=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args)	1038	=item packstring => $format, $data
369		1039
370	This function (not method) lets you add your own types to C<push_write>.	1040	An octet string prefixed with an encoded length. The encoding C<$format>
		1041	uses the same format as a Perl C<pack> format, but must specify a single
		1042	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1043	optional C<!>, C<< < >> or C<< > >> modifier).
		1044
		1045	=cut
		1046
		1047	register_write_type packstring => sub {
		1048	my ($self, $format, $string) = @_;
		1049
		1050	pack "$format/a*", $string
		1051	};
		1052
		1053	=item json => $array_or_hashref
		1054
		1055	Encodes the given hash or array reference into a JSON object. Unless you
		1056	provide your own JSON object, this means it will be encoded to JSON text
		1057	in UTF-8.
		1058
		1059	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		1060	one end of a handle and read them at the other end without using any
		1061	additional framing.
		1062
		1063	The generated JSON text is guaranteed not to contain any newlines: While
		1064	this module doesn't need delimiters after or between JSON texts to be
		1065	able to read them, many other languages depend on that.
		1066
		1067	A simple RPC protocol that interoperates easily with other languages is
		1068	to send JSON arrays (or objects, although arrays are usually the better
		1069	choice as they mimic how function argument passing works) and a newline
		1070	after each JSON text:
		1071
		1072	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		1073	$handle->push_write ("\012");
		1074
		1075	An AnyEvent::Handle receiver would simply use the C<json> read type and
		1076	rely on the fact that the newline will be skipped as leading whitespace:
		1077
		1078	$handle->push_read (json => sub { my $array = $_[1]; ... });
		1079
		1080	Other languages could read single lines terminated by a newline and pass
		1081	this line into their JSON decoder of choice.
		1082
		1083	=item cbor => $perl_scalar
		1084
		1085	Encodes the given scalar into a CBOR value. Unless you provide your own
		1086	L<CBOR::XS> object, this means it will be encoded to a CBOR string not
		1087	using any extensions, if possible.
		1088
		1089	CBOR values are self-delimiting, so you can write CBOR at one end of
		1090	a handle and read them at the other end without using any additional
		1091	framing.
		1092
		1093	A simple nd very very fast RPC protocol that interoperates with
		1094	other languages is to send CBOR and receive CBOR values (arrays are
		1095	recommended):
		1096
		1097	$handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
		1098
		1099	An AnyEvent::Handle receiver would simply use the C<cbor> read type:
		1100
		1101	$handle->push_read (cbor => sub { my $array = $_[1]; ... });
		1102
		1103	=cut
		1104
		1105	sub json_coder() {
		1106	eval { require JSON::XS; JSON::XS->new->utf8 }
		1107	|| do { require JSON::PP; JSON::PP->new->utf8 }
		1108	}
		1109
		1110	register_write_type json => sub {
		1111	my ($self, $ref) = @_;
		1112
		1113	($self->{json} ||= json_coder)
		1114	->encode ($ref)
		1115	};
		1116
		1117	sub cbor_coder() {
		1118	require CBOR::XS;
		1119	CBOR::XS->new
		1120	}
		1121
		1122	register_write_type cbor => sub {
		1123	my ($self, $scalar) = @_;
		1124
		1125	($self->{cbor} ||= cbor_coder)
		1126	->encode ($scalar)
		1127	};
		1128
		1129	=item storable => $reference
		1130
		1131	Freezes the given reference using L<Storable> and writes it to the
		1132	handle. Uses the C<nfreeze> format.
		1133
		1134	=cut
		1135
		1136	register_write_type storable => sub {
		1137	my ($self, $ref) = @_;
		1138
		1139	require Storable unless $Storable::VERSION;
		1140
		1141	pack "w/a*", Storable::nfreeze ($ref)
		1142	};
		1143
		1144	=back
		1145
		1146	=item $handle->push_shutdown
		1147
		1148	Sometimes you know you want to close the socket after writing your data
		1149	before it was actually written. One way to do that is to replace your
		1150	C<on_drain> handler by a callback that shuts down the socket (and set
		1151	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1152	replaces the C<on_drain> callback with:
		1153
		1154	sub { shutdown $_[0]{fh}, 1 }
		1155
		1156	This simply shuts down the write side and signals an EOF condition to the
		1157	the peer.
		1158
		1159	You can rely on the normal read queue and C<on_eof> handling
		1160	afterwards. This is the cleanest way to close a connection.
		1161
		1162	This method may invoke callbacks (and therefore the handle might be
		1163	destroyed after it returns).
		1164
		1165	=cut
		1166
		1167	sub push_shutdown {
		1168	my ($self) = @_;
		1169
		1170	delete $self->{low_water_mark};
		1171	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1172	}
		1173
		1174	=item custom write types - Package::anyevent_write_type $handle, @args
		1175
		1176	Instead of one of the predefined types, you can also specify the name of
		1177	a package. AnyEvent will try to load the package and then expects to find
		1178	a function named C<anyevent_write_type> inside. If it isn't found, it
		1179	progressively tries to load the parent package until it either finds the
		1180	function (good) or runs out of packages (bad).
		1181
371	Whenever the given C<type> is used, C<push_write> will invoke the code	1182	Whenever the given C<type> is used, C<push_write> will the function with
372	reference with the handle object and the remaining arguments.	1183	the handle object and the remaining arguments.
373		1184
374	The code reference is supposed to return a single octet string that will	1185	The function is supposed to return a single octet string that will be
375	be appended to the write buffer.	1186	appended to the write buffer, so you can mentally treat this function as a
		1187	"arguments to on-the-wire-format" converter.
376		1188
377	Note that this is a function, and all types registered this way will be	1189	Example: implement a custom write type C<join> that joins the remaining
378	global, so try to use unique names.	1190	arguments using the first one.
		1191
		1192	$handle->push_write (My::Type => " ", 1,2,3);
		1193
		1194	# uses the following package, which can be defined in the "My::Type" or in
		1195	# the "My" modules to be auto-loaded, or just about anywhere when the
		1196	# My::Type::anyevent_write_type is defined before invoking it.
		1197
		1198	package My::Type;
		1199
		1200	sub anyevent_write_type {
		1201	my ($handle, $delim, @args) = @_;
		1202
		1203	join $delim, @args
		1204	}
379		1205
380	=cut	1206	=cut
381		1207
382	#############################################################################	1208	#############################################################################
383		1209
…		…
392	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1218	ways, the "simple" way, using only C<on_read> and the "complex" way, using
393	a queue.	1219	a queue.
394		1220
395	In the simple case, you just install an C<on_read> callback and whenever	1221	In the simple case, you just install an C<on_read> callback and whenever
396	new data arrives, it will be called. You can then remove some data (if	1222	new data arrives, it will be called. You can then remove some data (if
397	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	1223	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
398	or not.	1224	leave the data there if you want to accumulate more (e.g. when only a
		1225	partial message has been received so far), or change the read queue with
		1226	e.g. C<push_read>.
399		1227
400	In the more complex case, you want to queue multiple callbacks. In this	1228	In the more complex case, you want to queue multiple callbacks. In this
401	case, AnyEvent::Handle will call the first queued callback each time new	1229	case, AnyEvent::Handle will call the first queued callback each time new
402	data arrives and removes it when it has done its job (see C<push_read>,	1230	data arrives (also the first time it is queued) and remove it when it has
403	below).	1231	done its job (see C<push_read>, below).
404		1232
405	This way you can, for example, push three line-reads, followed by reading	1233	This way you can, for example, push three line-reads, followed by reading
406	a chunk of data, and AnyEvent::Handle will execute them in order.	1234	a chunk of data, and AnyEvent::Handle will execute them in order.
407		1235
408	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	1236	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
409	the specified number of bytes which give an XML datagram.	1237	the specified number of bytes which give an XML datagram.
410		1238
411	# in the default state, expect some header bytes	1239	# in the default state, expect some header bytes
412	$handle->on_read (sub {	1240	$handle->on_read (sub {
413	# some data is here, now queue the length-header-read (4 octets)	1241	# some data is here, now queue the length-header-read (4 octets)
414	shift->unshift_read_chunk (4, sub {	1242	shift->unshift_read (chunk => 4, sub {
415	# header arrived, decode	1243	# header arrived, decode
416	my $len = unpack "N", $_[1];	1244	my $len = unpack "N", $_[1];
417		1245
418	# now read the payload	1246	# now read the payload
419	shift->unshift_read_chunk ($len, sub {	1247	shift->unshift_read (chunk => $len, sub {
420	my $xml = $_[1];	1248	my $xml = $_[1];
421	# handle xml	1249	# handle xml
422	});	1250	});
423	});	1251	});
424	});	1252	});
425		1253
426	Example 2: Implement a client for a protocol that replies either with	1254	Example 2: Implement a client for a protocol that replies either with "OK"
427	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1255	and another line or "ERROR" for the first request that is sent, and 64
428	second request. Due tot he availability of a full queue, we can just	1256	bytes for the second request. Due to the availability of a queue, we can
429	pipeline sending both requests and manipulate the queue as necessary in	1257	just pipeline sending both requests and manipulate the queue as necessary
430	the callbacks:	1258	in the callbacks.
431		1259
432	# request one	1260	When the first callback is called and sees an "OK" response, it will
		1261	C<unshift> another line-read. This line-read will be queued I<before> the
		1262	64-byte chunk callback.
		1263
		1264	# request one, returns either "OK + extra line" or "ERROR"
433	$handle->push_write ("request 1\015\012");	1265	$handle->push_write ("request 1\015\012");
434		1266
435	# we expect "ERROR" or "OK" as response, so push a line read	1267	# we expect "ERROR" or "OK" as response, so push a line read
436	$handle->push_read_line (sub {	1268	$handle->push_read (line => sub {
437	# if we got an "OK", we have to _prepend_ another line,	1269	# if we got an "OK", we have to _prepend_ another line,
438	# so it will be read before the second request reads its 64 bytes	1270	# so it will be read before the second request reads its 64 bytes
439	# which are already in the queue when this callback is called	1271	# which are already in the queue when this callback is called
440	# we don't do this in case we got an error	1272	# we don't do this in case we got an error
441	if ($_[1] eq "OK") {	1273	if ($_[1] eq "OK") {
442	$_[0]->unshift_read_line (sub {	1274	$_[0]->unshift_read (line => sub {
443	my $response = $_[1];	1275	my $response = $_[1];
444	...	1276	...
445	});	1277	});
446	}	1278	}
447	});	1279	});
448		1280
449	# request two	1281	# request two, simply returns 64 octets
450	$handle->push_write ("request 2\015\012");	1282	$handle->push_write ("request 2\015\012");
451		1283
452	# simply read 64 bytes, always	1284	# simply read 64 bytes, always
453	$handle->push_read_chunk (64, sub {	1285	$handle->push_read (chunk => 64, sub {
454	my $response = $_[1];	1286	my $response = $_[1];
455	...	1287	...
456	});	1288	});
457		1289
458	=over 4	1290	=over 4
459		1291
460	=cut	1292	=cut
461		1293
462	sub _drain_rbuf {	1294	sub _drain_rbuf {
463	my ($self) = @_;	1295	my ($self) = @_;
		1296
		1297	# avoid recursion
		1298	return if $self->{_skip_drain_rbuf};
		1299	local $self->{_skip_drain_rbuf} = 1;
		1300
		1301	while () {
		1302	# we need to use a separate tls read buffer, as we must not receive data while
		1303	# we are draining the buffer, and this can only happen with TLS.
		1304	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1305	if exists $self->{_tls_rbuf};
		1306
		1307	my $len = length $self->{rbuf};
		1308
		1309	if (my $cb = shift @{ $self->{_queue} }) {
		1310	unless ($cb->($self)) {
		1311	# no progress can be made
		1312	# (not enough data and no data forthcoming)
		1313	$self->_error (Errno::EPIPE, 1), return
		1314	if $self->{_eof};
		1315
		1316	unshift @{ $self->{_queue} }, $cb;
		1317	last;
		1318	}
		1319	} elsif ($self->{on_read}) {
		1320	last unless $len;
		1321
		1322	$self->{on_read}($self);
		1323
		1324	if (
		1325	$len == length $self->{rbuf} # if no data has been consumed
		1326	&& !@{ $self->{_queue} } # and the queue is still empty
		1327	&& $self->{on_read} # but we still have on_read
		1328	) {
		1329	# no further data will arrive
		1330	# so no progress can be made
		1331	$self->_error (Errno::EPIPE, 1), return
		1332	if $self->{_eof};
		1333
		1334	last; # more data might arrive
		1335	}
		1336	} else {
		1337	# read side becomes idle
		1338	delete $self->{_rw} unless $self->{tls};
		1339	last;
		1340	}
		1341	}
		1342
		1343	if ($self->{_eof}) {
		1344	$self->{on_eof}
		1345	? $self->{on_eof}($self)
		1346	: $self->_error (0, 1, "Unexpected end-of-file");
		1347
		1348	return;
		1349	}
464		1350
465	if (	1351	if (
466	defined $self->{rbuf_max}	1352	defined $self->{rbuf_max}
467	&& $self->{rbuf_max} < length $self->{rbuf}	1353	&& $self->{rbuf_max} < length $self->{rbuf}
468	) {	1354	) {
469	$! = &Errno::ENOSPC; return $self->error;	1355	$self->_error (Errno::ENOSPC, 1), return;
470	}	1356	}
471		1357
472	return if $self->{in_drain};	1358	# may need to restart read watcher
473	local $self->{in_drain} = 1;	1359	unless ($self->{_rw}) {
474		1360	$self->start_read
475	while (my $len = length $self->{rbuf}) {	1361	if $self->{on_read} || @{ $self->{_queue} };
476	no strict 'refs';
477	if (my $cb = shift @{ $self->{queue} }) {
478	unless ($cb->($self)) {
479	if ($self->{eof}) {
480	# no progress can be made (not enough data and no data forthcoming)
481	$! = &Errno::EPIPE; return $self->error;
482	}
483
484	unshift @{ $self->{queue} }, $cb;
485	return;
486	}
487	} elsif ($self->{on_read}) {
488	$self->{on_read}($self);
489
490	if (
491	$self->{eof} # if no further data will arrive
492	&& $len == length $self->{rbuf} # and no data has been consumed
493	&& !@{ $self->{queue} } # and the queue is still empty
494	&& $self->{on_read} # and we still want to read data
495	) {
496	# then no progress can be made
497	$! = &Errno::EPIPE; return $self->error;
498	}
499	} else {
500	# read side becomes idle
501	delete $self->{rw};
502	return;
503	}
504	}
505
506	if ($self->{eof}) {
507	$self->_shutdown;
508	$self->{on_eof}($self)
509	if $self->{on_eof};
510	}	1362	}
511	}	1363	}
512		1364
513	=item $handle->on_read ($cb)	1365	=item $handle->on_read ($cb)
514		1366
515	This replaces the currently set C<on_read> callback, or clears it (when	1367	This replaces the currently set C<on_read> callback, or clears it (when
516	the new callback is C<undef>). See the description of C<on_read> in the	1368	the new callback is C<undef>). See the description of C<on_read> in the
517	constructor.	1369	constructor.
518		1370
		1371	This method may invoke callbacks (and therefore the handle might be
		1372	destroyed after it returns).
		1373
519	=cut	1374	=cut
520		1375
521	sub on_read {	1376	sub on_read {
522	my ($self, $cb) = @_;	1377	my ($self, $cb) = @_;
523		1378
524	$self->{on_read} = $cb;	1379	$self->{on_read} = $cb;
		1380	$self->_drain_rbuf if $cb;
525	}	1381	}
526		1382
527	=item $handle->rbuf	1383	=item $handle->rbuf
528		1384
529	Returns the read buffer (as a modifiable lvalue).	1385	Returns the read buffer (as a modifiable lvalue). You can also access the
		1386	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1387	much faster, and no less clean).
530		1388
531	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1389	The only operation allowed on the read buffer (apart from looking at it)
532	you want.	1390	is removing data from its beginning. Otherwise modifying or appending to
		1391	it is not allowed and will lead to hard-to-track-down bugs.
533		1392
534	NOTE: The read buffer should only be used or modified if the C<on_read>,	1393	NOTE: The read buffer should only be used or modified in the C<on_read>
535	C<push_read> or C<unshift_read> methods are used. The other read methods	1394	callback or when C<push_read> or C<unshift_read> are used with a single
536	automatically manage the read buffer.	1395	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1396	will manage the read buffer on their own.
537		1397
538	=cut	1398	=cut
539		1399
540	sub rbuf : lvalue {	1400	sub rbuf : lvalue {
541	$_[0]{rbuf}	1401	$_[0]{rbuf}
…		…
558		1418
559	If enough data was available, then the callback must remove all data it is	1419	If enough data was available, then the callback must remove all data it is
560	interested in (which can be none at all) and return a true value. After returning	1420	interested in (which can be none at all) and return a true value. After returning
561	true, it will be removed from the queue.	1421	true, it will be removed from the queue.
562		1422
		1423	These methods may invoke callbacks (and therefore the handle might be
		1424	destroyed after it returns).
		1425
563	=cut	1426	=cut
564		1427
565	our %RH;	1428	our %RH;
566		1429
567	sub register_read_type($$) {	1430	sub register_read_type($$) {
…		…
573	my $cb = pop;	1436	my $cb = pop;
574		1437
575	if (@_) {	1438	if (@_) {
576	my $type = shift;	1439	my $type = shift;
577		1440
		1441	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
578	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1442	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
579	->($self, $cb, @_);	1443	->($self, $cb, @_);
580	}	1444	}
581		1445
582	push @{ $self->{queue} }, $cb;	1446	push @{ $self->{_queue} }, $cb;
583	$self->_drain_rbuf;	1447	$self->_drain_rbuf;
584	}	1448	}
585		1449
586	sub unshift_read {	1450	sub unshift_read {
587	my $self = shift;	1451	my $self = shift;
588	my $cb = pop;	1452	my $cb = pop;
589		1453
590	if (@_) {	1454	if (@_) {
591	my $type = shift;	1455	my $type = shift;
592		1456
		1457	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
593	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1458	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
594	->($self, $cb, @_);	1459	->($self, $cb, @_);
595	}	1460	}
596		1461
597
598	unshift @{ $self->{queue} }, $cb;	1462	unshift @{ $self->{_queue} }, $cb;
599	$self->_drain_rbuf;	1463	$self->_drain_rbuf;
600	}	1464	}
601		1465
602	=item $handle->push_read (type => @args, $cb)	1466	=item $handle->push_read (type => @args, $cb)
603		1467
604	=item $handle->unshift_read (type => @args, $cb)	1468	=item $handle->unshift_read (type => @args, $cb)
605		1469
606	Instead of providing a callback that parses the data itself you can chose	1470	Instead of providing a callback that parses the data itself you can chose
607	between a number of predefined parsing formats, for chunks of data, lines	1471	between a number of predefined parsing formats, for chunks of data, lines
608	etc.	1472	etc. You can also specify the (fully qualified) name of a package, in
		1473	which case AnyEvent tries to load the package and then expects to find the
		1474	C<anyevent_read_type> function inside (see "custom read types", below).
609		1475
610	Predefined types are (if you have ideas for additional types, feel free to	1476	Predefined types are (if you have ideas for additional types, feel free to
611	drop by and tell us):	1477	drop by and tell us):
612		1478
613	=over 4	1479	=over 4
614		1480
615	=item chunk => $octets, $cb->($self, $data)	1481	=item chunk => $octets, $cb->($handle, $data)
616		1482
617	Invoke the callback only once C<$octets> bytes have been read. Pass the	1483	Invoke the callback only once C<$octets> bytes have been read. Pass the
618	data read to the callback. The callback will never be called with less	1484	data read to the callback. The callback will never be called with less
619	data.	1485	data.
620		1486
621	Example: read 2 bytes.	1487	Example: read 2 bytes.
622		1488
623	$handle->push_read (chunk => 2, sub {	1489	$handle->push_read (chunk => 2, sub {
624	warn "yay ", unpack "H*", $_[1];	1490	say "yay " . unpack "H*", $_[1];
625	});	1491	});
626		1492
627	=cut	1493	=cut
628		1494
629	register_read_type chunk => sub {	1495	register_read_type chunk => sub {
…		…
634	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1500	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
635	1	1501	1
636	}	1502	}
637	};	1503	};
638		1504
639	# compatibility with older API
640	sub push_read_chunk {
641	$_[0]->push_read (chunk => $_[1], $_[2]);
642	}
643
644	sub unshift_read_chunk {
645	$_[0]->unshift_read (chunk => $_[1], $_[2]);
646	}
647
648	=item line => [$eol, ]$cb->($self, $line, $eol)	1505	=item line => [$eol, ]$cb->($handle, $line, $eol)
649		1506
650	The callback will be called only once a full line (including the end of	1507	The callback will be called only once a full line (including the end of
651	line marker, C<$eol>) has been read. This line (excluding the end of line	1508	line marker, C<$eol>) has been read. This line (excluding the end of line
652	marker) will be passed to the callback as second argument (C<$line>), and	1509	marker) will be passed to the callback as second argument (C<$line>), and
653	the end of line marker as the third argument (C<$eol>).	1510	the end of line marker as the third argument (C<$eol>).
…		…
667	=cut	1524	=cut
668		1525
669	register_read_type line => sub {	1526	register_read_type line => sub {
670	my ($self, $cb, $eol) = @_;	1527	my ($self, $cb, $eol) = @_;
671		1528
672	$eol = qr|(\015?\012)| if @_ < 3;	1529	if (@_ < 3) {
		1530	# this is faster then the generic code below
		1531	sub {
		1532	(my $pos = index $_[0]{rbuf}, "\012") >= 0
		1533	or return;
		1534
		1535	(my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
		1536	$cb->($_[0], $str, "$1");
		1537	1
		1538	}
		1539	} else {
673	$eol = quotemeta $eol unless ref $eol;	1540	$eol = quotemeta $eol unless ref $eol;
674	$eol = qr|^(.*?)($eol)|s;	1541	$eol = qr|^(.*?)($eol)|s;
		1542
		1543	sub {
		1544	$_[0]{rbuf} =~ s/$eol// or return;
		1545
		1546	$cb->($_[0], "$1", "$2");
		1547	1
		1548	}
		1549	}
		1550	};
		1551
		1552	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1553
		1554	Makes a regex match against the regex object C<$accept> and returns
		1555	everything up to and including the match.
		1556
		1557	Example: read a single line terminated by '\n'.
		1558
		1559	$handle->push_read (regex => qr<\n>, sub { ... });
		1560
		1561	If C<$reject> is given and not undef, then it determines when the data is
		1562	to be rejected: it is matched against the data when the C<$accept> regex
		1563	does not match and generates an C<EBADMSG> error when it matches. This is
		1564	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1565	receive buffer overflow).
		1566
		1567	Example: expect a single decimal number followed by whitespace, reject
		1568	anything else (not the use of an anchor).
		1569
		1570	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1571
		1572	If C<$skip> is given and not C<undef>, then it will be matched against
		1573	the receive buffer when neither C<$accept> nor C<$reject> match,
		1574	and everything preceding and including the match will be accepted
		1575	unconditionally. This is useful to skip large amounts of data that you
		1576	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1577	have to start matching from the beginning. This is purely an optimisation
		1578	and is usually worth it only when you expect more than a few kilobytes.
		1579
		1580	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1581	expect the header to be very large (it isn't in practice, but...), we use
		1582	a skip regex to skip initial portions. The skip regex is tricky in that
		1583	it only accepts something not ending in either \015 or \012, as these are
		1584	required for the accept regex.
		1585
		1586	$handle->push_read (regex =>
		1587	qr<\015\012\015\012>,
		1588	undef, # no reject
		1589	qr<^.*[^\015\012]>,
		1590	sub { ... });
		1591
		1592	=cut
		1593
		1594	register_read_type regex => sub {
		1595	my ($self, $cb, $accept, $reject, $skip) = @_;
		1596
		1597	my $data;
		1598	my $rbuf = \$self->{rbuf};
675		1599
676	sub {	1600	sub {
677	$_[0]{rbuf} =~ s/$eol// or return;	1601	# accept
678		1602	if ($$rbuf =~ $accept) {
		1603	$data .= substr $$rbuf, 0, $+[0], "";
679	$cb->($_[0], $1, $2);	1604	$cb->($_[0], $data);
		1605	return 1;
		1606	}
680	1	1607
		1608	# reject
		1609	if ($reject && $$rbuf =~ $reject) {
		1610	$_[0]->_error (Errno::EBADMSG);
		1611	}
		1612
		1613	# skip
		1614	if ($skip && $$rbuf =~ $skip) {
		1615	$data .= substr $$rbuf, 0, $+[0], "";
		1616	}
		1617
		1618	()
681	}	1619	}
682	};	1620	};
683		1621
684	# compatibility with older API
685	sub push_read_line {
686	my $self = shift;
687	$self->push_read (line => @_);
688	}
689
690	sub unshift_read_line {
691	my $self = shift;
692	$self->unshift_read (line => @_);
693	}
694
695	=item netstring => $cb->($string)	1622	=item netstring => $cb->($handle, $string)
696		1623
697	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).	1624	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
698		1625
699	Throws an error with C<$!> set to EBADMSG on format violations.	1626	Throws an error with C<$!> set to EBADMSG on format violations.
700		1627
…		…
704	my ($self, $cb) = @_;	1631	my ($self, $cb) = @_;
705		1632
706	sub {	1633	sub {
707	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1634	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
708	if ($_[0]{rbuf} =~ /[^0-9]/) {	1635	if ($_[0]{rbuf} =~ /[^0-9]/) {
709	$! = &Errno::EBADMSG;	1636	$_[0]->_error (Errno::EBADMSG);
710	$self->error;
711	}	1637	}
712	return;	1638	return;
713	}	1639	}
714		1640
715	my $len = $1;	1641	my $len = $1;
716		1642
717	$self->unshift_read (chunk => $len, sub {	1643	$_[0]->unshift_read (chunk => $len, sub {
718	my $string = $_[1];	1644	my $string = $_[1];
719	$_[0]->unshift_read (chunk => 1, sub {	1645	$_[0]->unshift_read (chunk => 1, sub {
720	if ($_[1] eq ",") {	1646	if ($_[1] eq ",") {
721	$cb->($_[0], $string);	1647	$cb->($_[0], $string);
722	} else {	1648	} else {
723	$! = &Errno::EBADMSG;	1649	$_[0]->_error (Errno::EBADMSG);
724	$self->error;
725	}	1650	}
726	});	1651	});
727	});	1652	});
728		1653
729	1	1654	1
730	}	1655	}
731	};	1656	};
732		1657
		1658	=item packstring => $format, $cb->($handle, $string)
		1659
		1660	An octet string prefixed with an encoded length. The encoding C<$format>
		1661	uses the same format as a Perl C<pack> format, but must specify a single
		1662	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1663	optional C<!>, C<< < >> or C<< > >> modifier).
		1664
		1665	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1666	EPP uses a prefix of C<N> (4 octtes).
		1667
		1668	Example: read a block of data prefixed by its length in BER-encoded
		1669	format (very efficient).
		1670
		1671	$handle->push_read (packstring => "w", sub {
		1672	my ($handle, $data) = @_;
		1673	});
		1674
		1675	=cut
		1676
		1677	register_read_type packstring => sub {
		1678	my ($self, $cb, $format) = @_;
		1679
		1680	sub {
		1681	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1682	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1683	or return;
		1684
		1685	$format = length pack $format, $len;
		1686
		1687	# bypass unshift if we already have the remaining chunk
		1688	if ($format + $len <= length $_[0]{rbuf}) {
		1689	my $data = substr $_[0]{rbuf}, $format, $len;
		1690	substr $_[0]{rbuf}, 0, $format + $len, "";
		1691	$cb->($_[0], $data);
		1692	} else {
		1693	# remove prefix
		1694	substr $_[0]{rbuf}, 0, $format, "";
		1695
		1696	# read remaining chunk
		1697	$_[0]->unshift_read (chunk => $len, $cb);
		1698	}
		1699
		1700	1
		1701	}
		1702	};
		1703
		1704	=item json => $cb->($handle, $hash_or_arrayref)
		1705
		1706	Reads a JSON object or array, decodes it and passes it to the
		1707	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1708
		1709	If a C<json> object was passed to the constructor, then that will be
		1710	used for the final decode, otherwise it will create a L<JSON::XS> or
		1711	L<JSON::PP> coder object expecting UTF-8.
		1712
		1713	This read type uses the incremental parser available with JSON version
		1714	2.09 (and JSON::XS version 2.2) and above.
		1715
		1716	Since JSON texts are fully self-delimiting, the C<json> read and write
		1717	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1718	the C<json> write type description, above, for an actual example.
		1719
		1720	=cut
		1721
		1722	register_read_type json => sub {
		1723	my ($self, $cb) = @_;
		1724
		1725	my $json = $self->{json} ||= json_coder;
		1726
		1727	my $data;
		1728
		1729	sub {
		1730	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
		1731
		1732	if ($ref) {
		1733	$_[0]{rbuf} = $json->incr_text;
		1734	$json->incr_text = "";
		1735	$cb->($_[0], $ref);
		1736
		1737	1
		1738	} elsif ($@) {
		1739	# error case
		1740	$json->incr_skip;
		1741
		1742	$_[0]{rbuf} = $json->incr_text;
		1743	$json->incr_text = "";
		1744
		1745	$_[0]->_error (Errno::EBADMSG);
		1746
		1747	()
		1748	} else {
		1749	$_[0]{rbuf} = "";
		1750
		1751	()
		1752	}
		1753	}
		1754	};
		1755
		1756	=item cbor => $cb->($handle, $scalar)
		1757
		1758	Reads a CBOR value, decodes it and passes it to the callback. When a parse
		1759	error occurs, an C<EBADMSG> error will be raised.
		1760
		1761	If a L<CBOR::XS> object was passed to the constructor, then that will be
		1762	used for the final decode, otherwise it will create a CBOR coder without
		1763	enabling any options.
		1764
		1765	You have to provide a dependency to L<CBOR::XS> on your own: this module
		1766	will load the L<CBOR::XS> module, but AnyEvent does not depend on it
		1767	itself.
		1768
		1769	Since CBOR values are fully self-delimiting, the C<cbor> read and write
		1770	types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
		1771	the C<cbor> write type description, above, for an actual example.
		1772
		1773	=cut
		1774
		1775	register_read_type cbor => sub {
		1776	my ($self, $cb) = @_;
		1777
		1778	my $cbor = $self->{cbor} ||= cbor_coder;
		1779
		1780	my $data;
		1781
		1782	sub {
		1783	my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
		1784
		1785	if (@value) {
		1786	$cb->($_[0], @value);
		1787
		1788	1
		1789	} elsif ($@) {
		1790	# error case
		1791	$cbor->incr_reset;
		1792
		1793	$_[0]->_error (Errno::EBADMSG);
		1794
		1795	()
		1796	} else {
		1797	()
		1798	}
		1799	}
		1800	};
		1801
		1802	=item storable => $cb->($handle, $ref)
		1803
		1804	Deserialises a L<Storable> frozen representation as written by the
		1805	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1806	data).
		1807
		1808	Raises C<EBADMSG> error if the data could not be decoded.
		1809
		1810	=cut
		1811
		1812	register_read_type storable => sub {
		1813	my ($self, $cb) = @_;
		1814
		1815	require Storable unless $Storable::VERSION;
		1816
		1817	sub {
		1818	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1819	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1820	or return;
		1821
		1822	my $format = length pack "w", $len;
		1823
		1824	# bypass unshift if we already have the remaining chunk
		1825	if ($format + $len <= length $_[0]{rbuf}) {
		1826	my $data = substr $_[0]{rbuf}, $format, $len;
		1827	substr $_[0]{rbuf}, 0, $format + $len, "";
		1828
		1829	eval { $cb->($_[0], Storable::thaw ($data)); 1 }
		1830	or return $_[0]->_error (Errno::EBADMSG);
		1831	} else {
		1832	# remove prefix
		1833	substr $_[0]{rbuf}, 0, $format, "";
		1834
		1835	# read remaining chunk
		1836	$_[0]->unshift_read (chunk => $len, sub {
		1837	eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
		1838	or $_[0]->_error (Errno::EBADMSG);
		1839	});
		1840	}
		1841
		1842	1
		1843	}
		1844	};
		1845
		1846	=item tls_detect => $cb->($handle, $detect, $major, $minor)
		1847
		1848	Checks the input stream for a valid SSL or TLS handshake TLSPaintext
		1849	record without consuming anything. Only SSL version 3 or higher
		1850	is handled, up to the fictituous protocol 4.x (but both SSL3+ and
		1851	SSL2-compatible framing is supported).
		1852
		1853	If it detects that the input data is likely TLS, it calls the callback
		1854	with a true value for C<$detect> and the (on-wire) TLS version as second
		1855	and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
		1856	3.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
		1857	be definitely not TLS, it calls the callback with a false value for
		1858	C<$detect>.
		1859
		1860	The callback could use this information to decide whether or not to start
		1861	TLS negotiation.
		1862
		1863	In all cases the data read so far is passed to the following read
		1864	handlers.
		1865
		1866	Usually you want to use the C<tls_autostart> read type instead.
		1867
		1868	If you want to design a protocol that works in the presence of TLS
		1869	dtection, make sure that any non-TLS data doesn't start with the octet 22
		1870	(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
		1871	read type does are a bit more strict, but might losen in the future to
		1872	accomodate protocol changes.
		1873
		1874	This read type does not rely on L<AnyEvent::TLS> (and thus, not on
		1875	L<Net::SSLeay>).
		1876
		1877	=item tls_autostart => $tls[, $tls_ctx]
		1878
		1879	Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
		1880	to start tls by calling C<starttls> with the given arguments.
		1881
		1882	In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
		1883	been configured to accept, as servers do not normally send a handshake on
		1884	their own and ths cannot be detected in this way.
		1885
		1886	See C<tls_detect> above for more details.
		1887
		1888	Example: give the client a chance to start TLS before accepting a text
		1889	line.
		1890
		1891	$hdl->push_read (tls_detect => "accept");
		1892	$hdl->push_read (line => sub {
		1893	print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
		1894	});
		1895
		1896	=cut
		1897
		1898	register_read_type tls_detect => sub {
		1899	my ($self, $cb) = @_;
		1900
		1901	sub {
		1902	# this regex matches a full or partial tls record
		1903	if (
		1904	# ssl3+: type(22=handshake) major(=3) minor(any) length_hi
		1905	$self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
		1906	# ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
		1907	or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
		1908	) {
		1909	return if 3 != length $1; # partial match, can't decide yet
		1910
		1911	# full match, valid TLS record
		1912	my ($major, $minor) = unpack "CC", $1;
		1913	$cb->($self, "accept", $major + $minor * 0.1);
		1914	} else {
		1915	# mismatch == guaranteed not TLS
		1916	$cb->($self, undef);
		1917	}
		1918
		1919	1
		1920	}
		1921	};
		1922
		1923	register_read_type tls_autostart => sub {
		1924	my ($self, @tls) = @_;
		1925
		1926	$RH{tls_detect}($self, sub {
		1927	return unless $_[1];
		1928	$_[0]->starttls (@tls);
		1929	})
		1930	};
		1931
733	=back	1932	=back
734		1933
735	=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args)	1934	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
736		1935
737	This function (not method) lets you add your own types to C<push_read>.	1936	Instead of one of the predefined types, you can also specify the name
		1937	of a package. AnyEvent will try to load the package and then expects to
		1938	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1939	progressively tries to load the parent package until it either finds the
		1940	function (good) or runs out of packages (bad).
738		1941
739	Whenever the given C<type> is used, C<push_read> will invoke the code	1942	Whenever this type is used, C<push_read> will invoke the function with the
740	reference with the handle object, the callback and the remaining	1943	handle object, the original callback and the remaining arguments.
741	arguments.
742		1944
743	The code reference is supposed to return a callback (usually a closure)	1945	The function is supposed to return a callback (usually a closure) that
744	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1946	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1947	mentally treat the function as a "configurable read type to read callback"
		1948	converter.
745		1949
746	It should invoke the passed callback when it is done reading (remember to	1950	It should invoke the original callback when it is done reading (remember
747	pass C<$self> as first argument as all other callbacks do that).	1951	to pass C<$handle> as first argument as all other callbacks do that,
		1952	although there is no strict requirement on this).
748		1953
749	Note that this is a function, and all types registered this way will be
750	global, so try to use unique names.
751
752	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1954	For examples, see the source of this module (F<perldoc -m
753	search for C<register_read_type>)).	1955	AnyEvent::Handle>, search for C<register_read_type>)).
754		1956
755	=item $handle->stop_read	1957	=item $handle->stop_read
756		1958
757	=item $handle->start_read	1959	=item $handle->start_read
758		1960
759	In rare cases you actually do not want to read anything from the	1961	In rare cases you actually do not want to read anything from the
760	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1962	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
761	any queued callbacks will be executed then. To start reading again, call	1963	any queued callbacks will be executed then. To start reading again, call
762	C<start_read>.	1964	C<start_read>.
763		1965
		1966	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1967	you change the C<on_read> callback or push/unshift a read callback, and it
		1968	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1969	there are any read requests in the queue.
		1970
		1971	In older versions of this module (<= 5.3), these methods had no effect,
		1972	as TLS does not support half-duplex connections. In current versions they
		1973	work as expected, as this behaviour is required to avoid certain resource
		1974	attacks, where the program would be forced to read (and buffer) arbitrary
		1975	amounts of data before being able to send some data. The drawback is that
		1976	some readings of the the SSL/TLS specifications basically require this
		1977	attack to be working, as SSL/TLS implementations might stall sending data
		1978	during a rehandshake.
		1979
		1980	As a guideline, during the initial handshake, you should not stop reading,
		1981	and as a client, it might cause problems, depending on your application.
		1982
764	=cut	1983	=cut
765		1984
766	sub stop_read {	1985	sub stop_read {
767	my ($self) = @_;	1986	my ($self) = @_;
768		1987
769	delete $self->{rw};	1988	delete $self->{_rw};
770	}	1989	}
771		1990
772	sub start_read {	1991	sub start_read {
773	my ($self) = @_;	1992	my ($self) = @_;
774		1993
775	unless ($self->{rw} || $self->{eof}) {	1994	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
776	Scalar::Util::weaken $self;	1995	Scalar::Util::weaken $self;
777		1996
778	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1997	$self->{_rw} = AE::io $self->{fh}, 0, sub {
779	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1998	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
780	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1999	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
781		2000
782	if ($len > 0) {	2001	if ($len > 0) {
783	$self->{filter_r}	2002	$self->{_activity} = $self->{_ractivity} = AE::now;
784	? $self->{filter_r}->($self, $rbuf)	2003
		2004	if ($self->{tls}) {
		2005	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		2006
		2007	&_dotls ($self);
		2008	} else {
785	: $self->_drain_rbuf;	2009	$self->_drain_rbuf;
		2010	}
		2011
		2012	if ($len == $self->{read_size}) {
		2013	$self->{read_size} *= 2;
		2014	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		2015	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		2016	}
786		2017
787	} elsif (defined $len) {	2018	} elsif (defined $len) {
788	delete $self->{rw};	2019	delete $self->{_rw};
789	$self->{eof} = 1;	2020	$self->{_eof} = 1;
790	$self->_drain_rbuf;	2021	$self->_drain_rbuf;
791		2022
792	} elsif ($! != EAGAIN && $! != EINTR) {	2023	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
793	return $self->error;	2024	return $self->_error ($!, 1);
794	}	2025	}
795	});	2026	};
796	}	2027	}
797	}	2028	}
798		2029
		2030	our $ERROR_SYSCALL;
		2031	our $ERROR_WANT_READ;
		2032
		2033	sub _tls_error {
		2034	my ($self, $err) = @_;
		2035
		2036	return $self->_error ($!, 1)
		2037	if $err == Net::SSLeay::ERROR_SYSCALL ();
		2038
		2039	my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		2040
		2041	# reduce error string to look less scary
		2042	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		2043
		2044	if ($self->{_on_starttls}) {
		2045	(delete $self->{_on_starttls})->($self, undef, $err);
		2046	&_freetls;
		2047	} else {
		2048	&_freetls;
		2049	$self->_error (Errno::EPROTO, 1, $err);
		2050	}
		2051	}
		2052
		2053	# poll the write BIO and send the data if applicable
		2054	# also decode read data if possible
		2055	# this is basiclaly our TLS state machine
		2056	# more efficient implementations are possible with openssl,
		2057	# but not with the buggy and incomplete Net::SSLeay.
799	sub _dotls {	2058	sub _dotls {
800	my ($self) = @_;	2059	my ($self) = @_;
801		2060
		2061	my $tmp;
		2062
802	if (length $self->{tls_wbuf}) {	2063	while (length $self->{_tls_wbuf}) {
803	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf})) > 0) {	2064	if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
804	substr $self->{tls_wbuf}, 0, $len, "";	2065	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		2066
		2067	return $self->_tls_error ($tmp)
		2068	if $tmp != $ERROR_WANT_READ
		2069	&& ($tmp != $ERROR_SYSCALL || $!);
		2070
		2071	last;
805	}	2072	}
806	}
807		2073
		2074	substr $self->{_tls_wbuf}, 0, $tmp, "";
		2075	}
		2076
808	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) {	2077	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		2078	unless (length $tmp) {
		2079	$self->{_on_starttls}
		2080	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		2081	&_freetls;
		2082
		2083	if ($self->{on_stoptls}) {
		2084	$self->{on_stoptls}($self);
		2085	return;
		2086	} else {
		2087	# let's treat SSL-eof as we treat normal EOF
		2088	delete $self->{_rw};
		2089	$self->{_eof} = 1;
		2090	}
		2091	}
		2092
		2093	$self->{_tls_rbuf} .= $tmp;
		2094	$self->_drain_rbuf;
		2095	$self->{tls} or return; # tls session might have gone away in callback
		2096	}
		2097
		2098	$tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
		2099	return $self->_tls_error ($tmp)
		2100	if $tmp != $ERROR_WANT_READ
		2101	&& ($tmp != $ERROR_SYSCALL || $!);
		2102
		2103	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
809	$self->{wbuf} .= $buf;	2104	$self->{wbuf} .= $tmp;
810	$self->_drain_wbuf;	2105	$self->_drain_wbuf;
		2106	$self->{tls} or return; # tls session might have gone away in callback
811	}	2107	}
812		2108
813	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {	2109	$self->{_on_starttls}
814	$self->{rbuf} .= $buf;	2110	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
815	$self->_drain_rbuf;	2111	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
816	}
817
818	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
819
820	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
821	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
822	$self->error;
823	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
824	$! = &Errno::EIO;
825	$self->error;
826	}
827
828	# all others are fine for our purposes
829	}
830	}	2112	}
831		2113
832	=item $handle->starttls ($tls[, $tls_ctx])	2114	=item $handle->starttls ($tls[, $tls_ctx])
833		2115
834	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	2116	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
835	object is created, you can also do that at a later time by calling	2117	object is created, you can also do that at a later time by calling
836	C<starttls>.	2118	C<starttls>. See the C<tls> constructor argument for general info.
		2119
		2120	Starting TLS is currently an asynchronous operation - when you push some
		2121	write data and then call C<< ->starttls >> then TLS negotiation will start
		2122	immediately, after which the queued write data is then sent. This might
		2123	change in future versions, so best make sure you have no outstanding write
		2124	data when calling this method.
837		2125
838	The first argument is the same as the C<tls> constructor argument (either	2126	The first argument is the same as the C<tls> constructor argument (either
839	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	2127	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
840		2128
841	The second argument is the optional C<Net::SSLeay::CTX> object that is	2129	The second argument is the optional C<AnyEvent::TLS> object that is used
842	used when AnyEvent::Handle has to create its own TLS connection object.	2130	when AnyEvent::Handle has to create its own TLS connection object, or
		2131	a hash reference with C<< key => value >> pairs that will be used to
		2132	construct a new context.
843		2133
844	=cut	2134	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
		2135	context in C<< $handle->{tls_ctx} >> after this call and can be used or
		2136	changed to your liking. Note that the handshake might have already started
		2137	when this function returns.
845		2138
846	# TODO: maybe document...	2139	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		2140	handshakes on the same stream. It is best to not attempt to use the
		2141	stream after stopping TLS.
		2142
		2143	This method may invoke callbacks (and therefore the handle might be
		2144	destroyed after it returns).
		2145
		2146	=cut
		2147
		2148	our %TLS_CACHE; #TODO not yet documented, should we?
		2149
847	sub starttls {	2150	sub starttls {
848	my ($self, $ssl, $ctx) = @_;	2151	my ($self, $tls, $ctx) = @_;
849		2152
850	$self->stoptls;	2153	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		2154	if $self->{tls};
851		2155
852	if ($ssl eq "accept") {	2156	unless (defined $AnyEvent::TLS::VERSION) {
853	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2157	eval {
854	Net::SSLeay::set_accept_state ($ssl);	2158	require Net::SSLeay;
855	} elsif ($ssl eq "connect") {	2159	require AnyEvent::TLS;
856	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2160	1
857	Net::SSLeay::set_connect_state ($ssl);	2161	} or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
		2162	}
		2163
		2164	$self->{tls} = $tls;
		2165	$self->{tls_ctx} = $ctx if @_ > 2;
		2166
		2167	return unless $self->{fh};
		2168
		2169	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		2170	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		2171
		2172	$tls = delete $self->{tls};
		2173	$ctx = $self->{tls_ctx};
		2174
		2175	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		2176
		2177	if ("HASH" eq ref $ctx) {
		2178	if ($ctx->{cache}) {
		2179	my $key = $ctx+0;
		2180	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		2181	} else {
		2182	$ctx = new AnyEvent::TLS %$ctx;
		2183	}
		2184	}
858	}	2185
859		2186	$self->{tls_ctx} = $ctx || TLS_CTX ();
860	$self->{tls} = $ssl;	2187	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
861		2188
862	# basically, this is deep magic (because SSL_read should have the same issues)	2189	# basically, this is deep magic (because SSL_read should have the same issues)
863	# but the openssl maintainers basically said: "trust us, it just works".	2190	# but the openssl maintainers basically said: "trust us, it just works".
864	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	2191	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
865	# and mismaintained ssleay-module doesn't even offer them).	2192	# and mismaintained ssleay-module doesn't even offer them).
866	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	2193	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		2194	#
		2195	# in short: this is a mess.
		2196	#
		2197	# note that we do not try to keep the length constant between writes as we are required to do.
		2198	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		2199	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		2200	# have identity issues in that area.
867	Net::SSLeay::CTX_set_mode ($self->{tls},	2201	# Net::SSLeay::CTX_set_mode ($ssl,
868	(eval { Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2202	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
869	| (eval { Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2203	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		2204	Net::SSLeay::CTX_set_mode ($tls, 1|2);
870		2205
871	$self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2206	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
872	$self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2207	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
873		2208
		2209	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2210	$self->{rbuf} = "";
		2211
874	Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio});	2212	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
875		2213
876	$self->{filter_w} = sub {	2214	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
877	$_[0]{tls_wbuf} .= ${$_[1]};	2215	if $self->{on_starttls};
878	&_dotls;	2216
879	};	2217	&_dotls; # need to trigger the initial handshake
880	$self->{filter_r} = sub {	2218	$self->start_read; # make sure we actually do read
881	Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
882	&_dotls;
883	};
884	}	2219	}
885		2220
886	=item $handle->stoptls	2221	=item $handle->stoptls
887		2222
888	Destroys the SSL connection, if any. Partial read or write data will be	2223	Shuts down the SSL connection - this makes a proper EOF handshake by
889	lost.	2224	sending a close notify to the other side, but since OpenSSL doesn't
		2225	support non-blocking shut downs, it is not guaranteed that you can re-use
		2226	the stream afterwards.
		2227
		2228	This method may invoke callbacks (and therefore the handle might be
		2229	destroyed after it returns).
890		2230
891	=cut	2231	=cut
892		2232
893	sub stoptls {	2233	sub stoptls {
894	my ($self) = @_;	2234	my ($self) = @_;
895		2235
896	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	2236	if ($self->{tls} && $self->{fh}) {
897	delete $self->{tls_rbio};	2237	Net::SSLeay::shutdown ($self->{tls});
898	delete $self->{tls_wbio};	2238
899	delete $self->{tls_wbuf};	2239	&_dotls;
900	delete $self->{filter_r};	2240
901	delete $self->{filter_w};	2241	# # we don't give a shit. no, we do, but we can't. no...#d#
		2242	# # we, we... have to use openssl :/#d#
		2243	# &_freetls;#d#
		2244	}
902	}	2245	}
		2246
		2247	sub _freetls {
		2248	my ($self) = @_;
		2249
		2250	return unless $self->{tls};
		2251
		2252	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2253	if $self->{tls} > 0;
		2254
		2255	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		2256	}
		2257
		2258	=item $handle->resettls
		2259
		2260	This rarely-used method simply resets and TLS state on the handle, usually
		2261	causing data loss.
		2262
		2263	One case where it may be useful is when you want to skip over the data in
		2264	the stream but you are not interested in interpreting it, so data loss is
		2265	no concern.
		2266
		2267	=cut
		2268
		2269	*resettls = \&_freetls;
903		2270
904	sub DESTROY {	2271	sub DESTROY {
905	my $self = shift;	2272	my ($self) = @_;
906		2273
907	$self->stoptls;	2274	&_freetls;
		2275
		2276	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		2277
		2278	if ($linger && length $self->{wbuf} && $self->{fh}) {
		2279	my $fh = delete $self->{fh};
		2280	my $wbuf = delete $self->{wbuf};
		2281
		2282	my @linger;
		2283
		2284	push @linger, AE::io $fh, 1, sub {
		2285	my $len = syswrite $fh, $wbuf, length $wbuf;
		2286
		2287	if ($len > 0) {
		2288	substr $wbuf, 0, $len, "";
		2289	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
		2290	@linger = (); # end
		2291	}
		2292	};
		2293	push @linger, AE::timer $linger, 0, sub {
		2294	@linger = ();
		2295	};
		2296	}
908	}	2297	}
		2298
		2299	=item $handle->destroy
		2300
		2301	Shuts down the handle object as much as possible - this call ensures that
		2302	no further callbacks will be invoked and as many resources as possible
		2303	will be freed. Any method you will call on the handle object after
		2304	destroying it in this way will be silently ignored (and it will return the
		2305	empty list).
		2306
		2307	Normally, you can just "forget" any references to an AnyEvent::Handle
		2308	object and it will simply shut down. This works in fatal error and EOF
		2309	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2310	callback, so when you want to destroy the AnyEvent::Handle object from
		2311	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2312	that case.
		2313
		2314	Destroying the handle object in this way has the advantage that callbacks
		2315	will be removed as well, so if those are the only reference holders (as
		2316	is common), then one doesn't need to do anything special to break any
		2317	reference cycles.
		2318
		2319	The handle might still linger in the background and write out remaining
		2320	data, as specified by the C<linger> option, however.
		2321
		2322	=cut
		2323
		2324	sub destroy {
		2325	my ($self) = @_;
		2326
		2327	$self->DESTROY;
		2328	%$self = ();
		2329	bless $self, "AnyEvent::Handle::destroyed";
		2330	}
		2331
		2332	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2333	#nop
		2334	}
		2335
		2336	=item $handle->destroyed
		2337
		2338	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2339	->destroy >>, true otherwise.
		2340
		2341	Can be useful to decide whether the handle is still valid after some
		2342	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2343	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2344	can destroy the handle, so work can be avoided by checking sometimes:
		2345
		2346	$hdl->starttls ("accept");
		2347	return if $hdl->destroyed;
		2348	$hdl->push_write (...
		2349
		2350	Note that the call to C<push_write> will silently be ignored if the handle
		2351	has been destroyed, so often you can just ignore the possibility of the
		2352	handle being destroyed.
		2353
		2354	=cut
		2355
		2356	sub destroyed { 0 }
		2357	sub AnyEvent::Handle::destroyed::destroyed { 1 }
909		2358
910	=item AnyEvent::Handle::TLS_CTX	2359	=item AnyEvent::Handle::TLS_CTX
911		2360
912	This function creates and returns the Net::SSLeay::CTX object used by	2361	This function creates and returns the AnyEvent::TLS object used by default
913	default for TLS mode.	2362	for TLS mode.
914		2363
915	The context is created like this:	2364	The context is created by calling L<AnyEvent::TLS> without any arguments.
916
917	Net::SSLeay::load_error_strings;
918	Net::SSLeay::SSLeay_add_ssl_algorithms;
919	Net::SSLeay::randomize;
920
921	my $CTX = Net::SSLeay::CTX_new;
922
923	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
924		2365
925	=cut	2366	=cut
926		2367
927	our $TLS_CTX;	2368	our $TLS_CTX;
928		2369
929	sub TLS_CTX() {	2370	sub TLS_CTX() {
930	$TLS_CTX || do {	2371	$TLS_CTX ||= do {
931	require Net::SSLeay;	2372	require AnyEvent::TLS;
932		2373
933	Net::SSLeay::load_error_strings ();	2374	new AnyEvent::TLS
934	Net::SSLeay::SSLeay_add_ssl_algorithms ();
935	Net::SSLeay::randomize ();
936
937	$TLS_CTX = Net::SSLeay::CTX_new ();
938
939	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
940
941	$TLS_CTX
942	}	2375	}
943	}	2376	}
944		2377
945	=back	2378	=back
946		2379
		2380
		2381	=head1 NONFREQUENTLY ASKED QUESTIONS
		2382
		2383	=over 4
		2384
		2385	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2386	still get further invocations!
		2387
		2388	That's because AnyEvent::Handle keeps a reference to itself when handling
		2389	read or write callbacks.
		2390
		2391	It is only safe to "forget" the reference inside EOF or error callbacks,
		2392	from within all other callbacks, you need to explicitly call the C<<
		2393	->destroy >> method.
		2394
		2395	=item Why is my C<on_eof> callback never called?
		2396
		2397	Probably because your C<on_error> callback is being called instead: When
		2398	you have outstanding requests in your read queue, then an EOF is
		2399	considered an error as you clearly expected some data.
		2400
		2401	To avoid this, make sure you have an empty read queue whenever your handle
		2402	is supposed to be "idle" (i.e. connection closes are O.K.). You can set
		2403	an C<on_read> handler that simply pushes the first read requests in the
		2404	queue.
		2405
		2406	See also the next question, which explains this in a bit more detail.
		2407
		2408	=item How can I serve requests in a loop?
		2409
		2410	Most protocols consist of some setup phase (authentication for example)
		2411	followed by a request handling phase, where the server waits for requests
		2412	and handles them, in a loop.
		2413
		2414	There are two important variants: The first (traditional, better) variant
		2415	handles requests until the server gets some QUIT command, causing it to
		2416	close the connection first (highly desirable for a busy TCP server). A
		2417	client dropping the connection is an error, which means this variant can
		2418	detect an unexpected detection close.
		2419
		2420	To handle this case, always make sure you have a non-empty read queue, by
		2421	pushing the "read request start" handler on it:
		2422
		2423	# we assume a request starts with a single line
		2424	my @start_request; @start_request = (line => sub {
		2425	my ($hdl, $line) = @_;
		2426
		2427	... handle request
		2428
		2429	# push next request read, possibly from a nested callback
		2430	$hdl->push_read (@start_request);
		2431	});
		2432
		2433	# auth done, now go into request handling loop
		2434	# now push the first @start_request
		2435	$hdl->push_read (@start_request);
		2436
		2437	By always having an outstanding C<push_read>, the handle always expects
		2438	some data and raises the C<EPIPE> error when the connction is dropped
		2439	unexpectedly.
		2440
		2441	The second variant is a protocol where the client can drop the connection
		2442	at any time. For TCP, this means that the server machine may run out of
		2443	sockets easier, and in general, it means you cannot distinguish a protocl
		2444	failure/client crash from a normal connection close. Nevertheless, these
		2445	kinds of protocols are common (and sometimes even the best solution to the
		2446	problem).
		2447
		2448	Having an outstanding read request at all times is possible if you ignore
		2449	C<EPIPE> errors, but this doesn't help with when the client drops the
		2450	connection during a request, which would still be an error.
		2451
		2452	A better solution is to push the initial request read in an C<on_read>
		2453	callback. This avoids an error, as when the server doesn't expect data
		2454	(i.e. is idly waiting for the next request, an EOF will not raise an
		2455	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2456	and simpler:
		2457
		2458	# auth done, now go into request handling loop
		2459	$hdl->on_read (sub {
		2460	my ($hdl) = @_;
		2461
		2462	# called each time we receive data but the read queue is empty
		2463	# simply start read the request
		2464
		2465	$hdl->push_read (line => sub {
		2466	my ($hdl, $line) = @_;
		2467
		2468	... handle request
		2469
		2470	# do nothing special when the request has been handled, just
		2471	# let the request queue go empty.
		2472	});
		2473	});
		2474
		2475	=item I get different callback invocations in TLS mode/Why can't I pause
		2476	reading?
		2477
		2478	Unlike, say, TCP, TLS connections do not consist of two independent
		2479	communication channels, one for each direction. Or put differently, the
		2480	read and write directions are not independent of each other: you cannot
		2481	write data unless you are also prepared to read, and vice versa.
		2482
		2483	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2484	callback invocations when you are not expecting any read data - the reason
		2485	is that AnyEvent::Handle always reads in TLS mode.
		2486
		2487	During the connection, you have to make sure that you always have a
		2488	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2489	connection (or when you no longer want to use it) you can call the
		2490	C<destroy> method.
		2491
		2492	=item How do I read data until the other side closes the connection?
		2493
		2494	If you just want to read your data into a perl scalar, the easiest way
		2495	to achieve this is by setting an C<on_read> callback that does nothing,
		2496	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2497	will be in C<$_[0]{rbuf}>:
		2498
		2499	$handle->on_read (sub { });
		2500	$handle->on_eof (undef);
		2501	$handle->on_error (sub {
		2502	my $data = delete $_[0]{rbuf};
		2503	});
		2504
		2505	Note that this example removes the C<rbuf> member from the handle object,
		2506	which is not normally allowed by the API. It is expressly permitted in
		2507	this case only, as the handle object needs to be destroyed afterwards.
		2508
		2509	The reason to use C<on_error> is that TCP connections, due to latencies
		2510	and packets loss, might get closed quite violently with an error, when in
		2511	fact all data has been received.
		2512
		2513	It is usually better to use acknowledgements when transferring data,
		2514	to make sure the other side hasn't just died and you got the data
		2515	intact. This is also one reason why so many internet protocols have an
		2516	explicit QUIT command.
		2517
		2518	=item I don't want to destroy the handle too early - how do I wait until
		2519	all data has been written?
		2520
		2521	After writing your last bits of data, set the C<on_drain> callback
		2522	and destroy the handle in there - with the default setting of
		2523	C<low_water_mark> this will be called precisely when all data has been
		2524	written to the socket:
		2525
		2526	$handle->push_write (...);
		2527	$handle->on_drain (sub {
		2528	AE::log debug => "All data submitted to the kernel.";
		2529	undef $handle;
		2530	});
		2531
		2532	If you just want to queue some data and then signal EOF to the other side,
		2533	consider using C<< ->push_shutdown >> instead.
		2534
		2535	=item I want to contact a TLS/SSL server, I don't care about security.
		2536
		2537	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2538	connect to it and then create the AnyEvent::Handle with the C<tls>
		2539	parameter:
		2540
		2541	tcp_connect $host, $port, sub {
		2542	my ($fh) = @_;
		2543
		2544	my $handle = new AnyEvent::Handle
		2545	fh => $fh,
		2546	tls => "connect",
		2547	on_error => sub { ... };
		2548
		2549	$handle->push_write (...);
		2550	};
		2551
		2552	=item I want to contact a TLS/SSL server, I do care about security.
		2553
		2554	Then you should additionally enable certificate verification, including
		2555	peername verification, if the protocol you use supports it (see
		2556	L<AnyEvent::TLS>, C<verify_peername>).
		2557
		2558	E.g. for HTTPS:
		2559
		2560	tcp_connect $host, $port, sub {
		2561	my ($fh) = @_;
		2562
		2563	my $handle = new AnyEvent::Handle
		2564	fh => $fh,
		2565	peername => $host,
		2566	tls => "connect",
		2567	tls_ctx => { verify => 1, verify_peername => "https" },
		2568	...
		2569
		2570	Note that you must specify the hostname you connected to (or whatever
		2571	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2572	peername verification will be done.
		2573
		2574	The above will use the system-dependent default set of trusted CA
		2575	certificates. If you want to check against a specific CA, add the
		2576	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2577
		2578	tls_ctx => {
		2579	verify => 1,
		2580	verify_peername => "https",
		2581	ca_file => "my-ca-cert.pem",
		2582	},
		2583
		2584	=item I want to create a TLS/SSL server, how do I do that?
		2585
		2586	Well, you first need to get a server certificate and key. You have
		2587	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2588	self-signed certificate (cheap. check the search engine of your choice,
		2589	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2590	nice program for that purpose).
		2591
		2592	Then create a file with your private key (in PEM format, see
		2593	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2594	file should then look like this:
		2595
		2596	-----BEGIN RSA PRIVATE KEY-----
		2597	...header data
		2598	... lots of base64'y-stuff
		2599	-----END RSA PRIVATE KEY-----
		2600
		2601	-----BEGIN CERTIFICATE-----
		2602	... lots of base64'y-stuff
		2603	-----END CERTIFICATE-----
		2604
		2605	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2606	specify this file as C<cert_file>:
		2607
		2608	tcp_server undef, $port, sub {
		2609	my ($fh) = @_;
		2610
		2611	my $handle = new AnyEvent::Handle
		2612	fh => $fh,
		2613	tls => "accept",
		2614	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2615	...
		2616
		2617	When you have intermediate CA certificates that your clients might not
		2618	know about, just append them to the C<cert_file>.
		2619
		2620	=back
		2621
		2622	=head1 SUBCLASSING AnyEvent::Handle
		2623
		2624	In many cases, you might want to subclass AnyEvent::Handle.
		2625
		2626	To make this easier, a given version of AnyEvent::Handle uses these
		2627	conventions:
		2628
		2629	=over 4
		2630
		2631	=item * all constructor arguments become object members.
		2632
		2633	At least initially, when you pass a C<tls>-argument to the constructor it
		2634	will end up in C<< $handle->{tls} >>. Those members might be changed or
		2635	mutated later on (for example C<tls> will hold the TLS connection object).
		2636
		2637	=item * other object member names are prefixed with an C<_>.
		2638
		2639	All object members not explicitly documented (internal use) are prefixed
		2640	with an underscore character, so the remaining non-C<_>-namespace is free
		2641	for use for subclasses.
		2642
		2643	=item * all members not documented here and not prefixed with an underscore
		2644	are free to use in subclasses.
		2645
		2646	Of course, new versions of AnyEvent::Handle may introduce more "public"
		2647	member variables, but that's just life. At least it is documented.
		2648
		2649	=back
		2650
947	=head1 AUTHOR	2651	=head1 AUTHOR
948		2652
949	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	2653	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
950		2654
951	=cut	2655	=cut
952		2656
953	1; # End of AnyEvent::Handle	2657	1
		2658

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