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Revision 1.245 by root, Tue Jun 16 03:22:20 2015 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 EWOULDBLOCK 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::fh_unblock>) 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, $retry->())
		129
		130	This callback is called when a connection has been successfully established.
		131
		132	The peer's numeric host and port (the socket peername) are passed as
		133	parameters, together with a retry callback. At the time it is called the
		134	read and write queues, EOF status, TLS status and similar properties of
		135	the handle will have been reset.
		136
		137	If, for some reason, the handle is not acceptable, calling C<$retry> will
		138	continue with the next connection target (in case of multi-homed hosts or
		139	SRV records there can be multiple connection endpoints). The C<$retry>
		140	callback can be invoked after the connect callback returns, i.e. one can
		141	start a handshake and then decide to retry with the next host if the
		142	handshake fails.
		143
		144	In most cases, you should ignore the C<$retry> parameter.
		145
		146	=item on_connect_error => $cb->($handle, $message)
		147
		148	This callback is called when the connection could not be
		149	established. C<$!> will contain the relevant error code, and C<$message> a
		150	message describing it (usually the same as C<"$!">).
		151
		152	If this callback isn't specified, then C<on_error> will be called with a
		153	fatal error instead.
		154
		155	=back
		156
		157	=item on_error => $cb->($handle, $fatal, $message)
		158
88	This is the fatal error callback, that is called when, well, a fatal error	159	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	160	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	161	connect, or a read error.
91		162
92	The object will not be in a usable state when this callback has been	163	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	164	fatal errors the handle object will be destroyed (by a call to C<< ->
		165	destroy >>) after invoking the error callback (which means you are free to
		166	examine the handle object). Examples of fatal errors are an EOF condition
		167	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		168	cases where the other side can close the connection at will, it is
		169	often easiest to not report C<EPIPE> errors in this callback.
94		170
		171	AnyEvent::Handle tries to find an appropriate error code for you to check
		172	against, but in some cases (TLS errors), this does not work well.
		173
		174	If you report the error to the user, it is recommended to always output
		175	the C<$message> argument in human-readable error messages (you don't need
		176	to report C<"$!"> if you report C<$message>).
		177
		178	If you want to react programmatically to the error, then looking at C<$!>
		179	and comparing it against some of the documented C<Errno> values is usually
		180	better than looking at the C<$message>.
		181
		182	Non-fatal errors can be retried by returning, but it is recommended
		183	to simply ignore this parameter and instead abondon the handle object
		184	when this callback is invoked. Examples of non-fatal errors are timeouts
		185	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		186
95	On callback entrance, the value of C<$!> contains the operating system	187	On entry to the callback, the value of C<$!> contains the operating
96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).	188	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		189	C<EPROTO>).
97		190
98	While not mandatory, it is I<highly> recommended to set this callback, as	191	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	192	you will not be notified of errors otherwise. The default just calls
100	die.	193	C<croak>.
101		194
102	=item on_read => $cb->($self)	195	=item on_read => $cb->($handle)
103		196
104	This sets the default read callback, which is called when data arrives	197	This sets the default read callback, which is called when data arrives
105	and no read request is in the queue.	198	and no read request is in the queue (unlike read queue callbacks, this
		199	callback will only be called when at least one octet of data is in the
		200	read buffer).
106		201
107	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	202	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
108	method or access the C<$self->{rbuf}> member directly.	203	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		204	must not enlarge or modify the read buffer, you can only remove data at
		205	the beginning from it.
109		206
		207	You can also call C<< ->push_read (...) >> or any other function that
		208	modifies the read queue. Or do both. Or ...
		209
110	When an EOF condition is detected then AnyEvent::Handle will first try to	210	When an EOF condition is detected, AnyEvent::Handle will first try to
111	feed all the remaining data to the queued callbacks and C<on_read> before	211	feed all the remaining data to the queued callbacks and C<on_read> before
112	calling the C<on_eof> callback. If no progress can be made, then a fatal	212	calling the C<on_eof> callback. If no progress can be made, then a fatal
113	error will be raised (with C<$!> set to C<EPIPE>).	213	error will be raised (with C<$!> set to C<EPIPE>).
114		214
		215	Note that, unlike requests in the read queue, an C<on_read> callback
		216	doesn't mean you I<require> some data: if there is an EOF and there
		217	are outstanding read requests then an error will be flagged. With an
		218	C<on_read> callback, the C<on_eof> callback will be invoked.
		219
		220	=item on_eof => $cb->($handle)
		221
		222	Set the callback to be called when an end-of-file condition is detected,
		223	i.e. in the case of a socket, when the other side has closed the
		224	connection cleanly, and there are no outstanding read requests in the
		225	queue (if there are read requests, then an EOF counts as an unexpected
		226	connection close and will be flagged as an error).
		227
		228	For sockets, this just means that the other side has stopped sending data,
		229	you can still try to write data, and, in fact, one can return from the EOF
		230	callback and continue writing data, as only the read part has been shut
		231	down.
		232
		233	If an EOF condition has been detected but no C<on_eof> callback has been
		234	set, then a fatal error will be raised with C<$!> set to <0>.
		235
115	=item on_drain => $cb->()	236	=item on_drain => $cb->($handle)
116		237
117	This sets the callback that is called when the write buffer becomes empty	238	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).	239	empty (and immediately when the handle object is created).
119		240
120	To append to the write buffer, use the C<< ->push_write >> method.	241	To append to the write buffer, use the C<< ->push_write >> method.
		242
		243	This callback is useful when you don't want to put all of your write data
		244	into the queue at once, for example, when you want to write the contents
		245	of some file to the socket you might not want to read the whole file into
		246	memory and push it into the queue, but instead only read more data from
		247	the file when the write queue becomes empty.
		248
		249	=item timeout => $fractional_seconds
		250
		251	=item rtimeout => $fractional_seconds
		252
		253	=item wtimeout => $fractional_seconds
		254
		255	If non-zero, then these enables an "inactivity" timeout: whenever this
		256	many seconds pass without a successful read or write on the underlying
		257	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
		258	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		259	error will be raised).
		260
		261	There are three variants of the timeouts that work independently of each
		262	other, for both read and write (triggered when nothing was read I<OR>
		263	written), just read (triggered when nothing was read), and just write:
		264	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		265	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		266	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		267
		268	Note that timeout processing is active even when you do not have any
		269	outstanding read or write requests: If you plan to keep the connection
		270	idle then you should disable the timeout temporarily or ignore the
		271	timeout in the corresponding C<on_timeout> callback, in which case
		272	AnyEvent::Handle will simply restart the timeout.
		273
		274	Zero (the default) disables the corresponding timeout.
		275
		276	=item on_timeout => $cb->($handle)
		277
		278	=item on_rtimeout => $cb->($handle)
		279
		280	=item on_wtimeout => $cb->($handle)
		281
		282	Called whenever the inactivity timeout passes. If you return from this
		283	callback, then the timeout will be reset as if some activity had happened,
		284	so this condition is not fatal in any way.
121		285
122	=item rbuf_max => <bytes>	286	=item rbuf_max => <bytes>
123		287
124	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	288	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
125	when the read buffer ever (strictly) exceeds this size. This is useful to	289	when the read buffer ever (strictly) exceeds this size. This is useful to
126	avoid denial-of-service attacks.	290	avoid some forms of denial-of-service attacks.
127		291
128	For example, a server accepting connections from untrusted sources should	292	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	293	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	294	(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	295	amount of data without a callback ever being called as long as the line
132	isn't finished).	296	isn't finished).
133		297
		298	=item wbuf_max => <bytes>
		299
		300	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		301	when the write buffer ever (strictly) exceeds this size. This is useful to
		302	avoid some forms of denial-of-service attacks.
		303
		304	Although the units of this parameter is bytes, this is the I<raw> number
		305	of bytes not yet accepted by the kernel. This can make a difference when
		306	you e.g. use TLS, as TLS typically makes your write data larger (but it
		307	can also make it smaller due to compression).
		308
		309	As an example of when this limit is useful, take a chat server that sends
		310	chat messages to a client. If the client does not read those in a timely
		311	manner then the send buffer in the server would grow unbounded.
		312
		313	=item autocork => <boolean>
		314
		315	When disabled (the default), C<push_write> will try to immediately
		316	write the data to the handle if possible. This avoids having to register
		317	a write watcher and wait for the next event loop iteration, but can
		318	be inefficient if you write multiple small chunks (on the wire, this
		319	disadvantage is usually avoided by your kernel's nagle algorithm, see
		320	C<no_delay>, but this option can save costly syscalls).
		321
		322	When enabled, writes will always be queued till the next event loop
		323	iteration. This is efficient when you do many small writes per iteration,
		324	but less efficient when you do a single write only per iteration (or when
		325	the write buffer often is full). It also increases write latency.
		326
		327	=item no_delay => <boolean>
		328
		329	When doing small writes on sockets, your operating system kernel might
		330	wait a bit for more data before actually sending it out. This is called
		331	the Nagle algorithm, and usually it is beneficial.
		332
		333	In some situations you want as low a delay as possible, which can be
		334	accomplishd by setting this option to a true value.
		335
		336	The default is your operating system's default behaviour (most likely
		337	enabled). This option explicitly enables or disables it, if possible.
		338
		339	=item keepalive => <boolean>
		340
		341	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		342	normally, TCP connections have no time-out once established, so TCP
		343	connections, once established, can stay alive forever even when the other
		344	side has long gone. TCP keepalives are a cheap way to take down long-lived
		345	TCP connections when the other side becomes unreachable. While the default
		346	is OS-dependent, TCP keepalives usually kick in after around two hours,
		347	and, if the other side doesn't reply, take down the TCP connection some 10
		348	to 15 minutes later.
		349
		350	It is harmless to specify this option for file handles that do not support
		351	keepalives, and enabling it on connections that are potentially long-lived
		352	is usually a good idea.
		353
		354	=item oobinline => <boolean>
		355
		356	BSD majorly fucked up the implementation of TCP urgent data. The result
		357	is that almost no OS implements TCP according to the specs, and every OS
		358	implements it slightly differently.
		359
		360	If you want to handle TCP urgent data, then setting this flag (the default
		361	is enabled) gives you the most portable way of getting urgent data, by
		362	putting it into the stream.
		363
		364	Since BSD emulation of OOB data on top of TCP's urgent data can have
		365	security implications, AnyEvent::Handle sets this flag automatically
		366	unless explicitly specified. Note that setting this flag after
		367	establishing a connection I<may> be a bit too late (data loss could
		368	already have occured on BSD systems), but at least it will protect you
		369	from most attacks.
		370
134	=item read_size => <bytes>	371	=item read_size => <bytes>
135		372
136	The default read block size (the amount of bytes this module will try to read	373	The initial read block size, the number of bytes this module will try
137	on each [loop iteration). Default: C<4096>.	374	to read during each loop iteration. Each handle object will consume
		375	at least this amount of memory for the read buffer as well, so when
		376	handling many connections watch out for memory requirements). See also
		377	C<max_read_size>. Default: C<2048>.
		378
		379	=item max_read_size => <bytes>
		380
		381	The maximum read buffer size used by the dynamic adjustment
		382	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		383	one go it will double C<read_size> up to the maximum given by this
		384	option. Default: C<131072> or C<read_size>, whichever is higher.
138		385
139	=item low_water_mark => <bytes>	386	=item low_water_mark => <bytes>
140		387
141	Sets the amount of bytes (default: C<0>) that make up an "empty" write	388	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	389	buffer: If the buffer reaches this size or gets even samller it is
143	considered empty.	390	considered empty.
144		391
		392	Sometimes it can be beneficial (for performance reasons) to add data to
		393	the write buffer before it is fully drained, but this is a rare case, as
		394	the operating system kernel usually buffers data as well, so the default
		395	is good in almost all cases.
		396
		397	=item linger => <seconds>
		398
		399	If this is non-zero (default: C<3600>), the destructor of the
		400	AnyEvent::Handle object will check whether there is still outstanding
		401	write data and will install a watcher that will write this data to the
		402	socket. No errors will be reported (this mostly matches how the operating
		403	system treats outstanding data at socket close time).
		404
		405	This will not work for partial TLS data that could not be encoded
		406	yet. This data will be lost. Calling the C<stoptls> method in time might
		407	help.
		408
		409	=item peername => $string
		410
		411	A string used to identify the remote site - usually the DNS hostname
		412	(I<not> IDN!) used to create the connection, rarely the IP address.
		413
		414	Apart from being useful in error messages, this string is also used in TLS
		415	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		416	verification will be skipped when C<peername> is not specified or is
		417	C<undef>.
		418
145	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	419	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
146		420
147	When this parameter is given, it enables TLS (SSL) mode, that means it	421	When this parameter is given, it enables TLS (SSL) mode, that means
148	will start making tls handshake and will transparently encrypt/decrypt	422	AnyEvent will start a TLS handshake as soon as the connection has been
149	data.	423	established and will transparently encrypt/decrypt data afterwards.
		424
		425	All TLS protocol errors will be signalled as C<EPROTO>, with an
		426	appropriate error message.
150		427
151	TLS mode requires Net::SSLeay to be installed (it will be loaded	428	TLS mode requires Net::SSLeay to be installed (it will be loaded
152	automatically when you try to create a TLS handle).	429	automatically when you try to create a TLS handle): this module doesn't
		430	have a dependency on that module, so if your module requires it, you have
		431	to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
		432	old, you get an C<EPROTO> error.
153		433
154	For the TLS server side, use C<accept>, and for the TLS client side of a	434	Unlike TCP, TLS has a server and client side: for the TLS server side, use
155	connection, use C<connect> mode.	435	C<accept>, and for the TLS client side of a connection, use C<connect>
		436	mode.
156		437
157	You can also provide your own TLS connection object, but you have	438	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>	439	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	440	or C<Net::SSLeay::set_accept_state> on it before you pass it to
160	AnyEvent::Handle.	441	AnyEvent::Handle. Also, this module will take ownership of this connection
		442	object.
161		443
		444	At some future point, AnyEvent::Handle might switch to another TLS
		445	implementation, then the option to use your own session object will go
		446	away.
		447
		448	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		449	passing in the wrong integer will lead to certain crash. This most often
		450	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		451	segmentation fault.
		452
162	See the C<starttls> method if you need to start TLs negotiation later.	453	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
163		454
164	=item tls_ctx => $ssl_ctx	455	=item tls_ctx => $anyevent_tls
165		456
166	Use the given Net::SSLeay::CTX object to create the new TLS connection	457	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	458	(unless a connection object was specified directly). If this
168	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	459	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		460	C<AnyEvent::Handle::TLS_CTX>.
		461
		462	Instead of an object, you can also specify a hash reference with C<< key
		463	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		464	new TLS context object.
		465
		466	=item on_starttls => $cb->($handle, $success[, $error_message])
		467
		468	This callback will be invoked when the TLS/SSL handshake has finished. If
		469	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		470	(C<on_stoptls> will not be called in this case).
		471
		472	The session in C<< $handle->{tls} >> can still be examined in this
		473	callback, even when the handshake was not successful.
		474
		475	TLS handshake failures will not cause C<on_error> to be invoked when this
		476	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		477
		478	Without this callback, handshake failures lead to C<on_error> being
		479	called as usual.
		480
		481	Note that you cannot just call C<starttls> again in this callback. If you
		482	need to do that, start an zero-second timer instead whose callback can
		483	then call C<< ->starttls >> again.
		484
		485	=item on_stoptls => $cb->($handle)
		486
		487	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		488	set, then it will be invoked after freeing the TLS session. If it is not,
		489	then a TLS shutdown condition will be treated like a normal EOF condition
		490	on the handle.
		491
		492	The session in C<< $handle->{tls} >> can still be examined in this
		493	callback.
		494
		495	This callback will only be called on TLS shutdowns, not when the
		496	underlying handle signals EOF.
		497
		498	=item json => L<JSON>, L<JSON::PP> or L<JSON::XS> object
		499
		500	This is the json coder object used by the C<json> read and write types.
		501
		502	If you don't supply it, then AnyEvent::Handle will create and use a
		503	suitable one (on demand), which will write and expect UTF-8 encoded
		504	JSON texts (either using L<JSON::XS> or L<JSON>). The written texts are
		505	guaranteed not to contain any newline character.
		506
		507	For security reasons, this encoder will likely I<not> handle numbers and
		508	strings, only arrays and objects/hashes. The reason is that originally
		509	JSON was self-delimited, but Dougles Crockford thought it was a splendid
		510	idea to redefine JSON incompatibly, so this is no longer true.
		511
		512	For protocols that used back-to-back JSON texts, this might lead to
		513	run-ins, where two or more JSON texts will be interpreted as one JSON
		514	text.
		515
		516	For this reason, if the default encoder uses L<JSON::XS>, it will default
		517	to not allowing anything but arrays and objects/hashes, at least for the
		518	forseeable future (it will change at some point). This might or might not
		519	be true for the L<JSON> module, so this might cause a security issue.
		520
		521	If you depend on either behaviour, you should create your own json object
		522	and pass it in explicitly.
		523
		524	=item cbor => L<CBOR::XS> object
		525
		526	This is the cbor coder object used by the C<cbor> read and write types.
		527
		528	If you don't supply it, then AnyEvent::Handle will create and use a
		529	suitable one (on demand), which will write CBOR without using extensions,
		530	if possible.
		531
		532	Note that you are responsible to depend on the L<CBOR::XS> module if you
		533	want to use this functionality, as AnyEvent does not have a dependency on
		534	it itself.
169		535
170	=back	536	=back
171		537
172	=cut	538	=cut
173		539
174	sub new {	540	sub new {
175	my $class = shift;	541	my $class = shift;
176
177	my $self = bless { @_ }, $class;	542	my $self = bless { @_ }, $class;
178		543
179	$self->{fh} or Carp::croak "mandatory argument fh is missing";
180
181	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
182
183	if ($self->{tls}) {	544	if ($self->{fh}) {
184	require Net::SSLeay;
185	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
186	}
187
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};
191	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
192
193	$self->start_read;	545	$self->_start;
		546	return unless $self->{fh}; # could be gone by now
		547
		548	} elsif ($self->{connect}) {
		549	require AnyEvent::Socket;
		550
		551	$self->{peername} = $self->{connect}[0]
		552	unless exists $self->{peername};
		553
		554	$self->{_skip_drain_rbuf} = 1;
		555
		556	{
		557	Scalar::Util::weaken (my $self = $self);
		558
		559	$self->{_connect} =
		560	AnyEvent::Socket::tcp_connect (
		561	$self->{connect}[0],
		562	$self->{connect}[1],
		563	sub {
		564	my ($fh, $host, $port, $retry) = @_;
		565
		566	delete $self->{_connect}; # no longer needed
		567
		568	if ($fh) {
		569	$self->{fh} = $fh;
		570
		571	delete $self->{_skip_drain_rbuf};
		572	$self->_start;
		573
		574	$self->{on_connect}
		575	and $self->{on_connect}($self, $host, $port, sub {
		576	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		577	$self->{_skip_drain_rbuf} = 1;
		578	&$retry;
		579	});
		580
		581	} else {
		582	if ($self->{on_connect_error}) {
		583	$self->{on_connect_error}($self, "$!");
		584	$self->destroy if $self;
		585	} else {
		586	$self->_error ($!, 1);
		587	}
		588	}
		589	},
		590	sub {
		591	local $self->{fh} = $_[0];
		592
		593	$self->{on_prepare}
		594	? $self->{on_prepare}->($self)
		595	: ()
		596	}
		597	);
		598	}
		599
		600	} else {
		601	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		602	}
194		603
195	$self	604	$self
196	}	605	}
197		606
198	sub _shutdown {	607	sub _start {
199	my ($self) = @_;	608	my ($self) = @_;
200		609
201	delete $self->{rw};	610	# too many clueless people try to use udp and similar sockets
202	delete $self->{ww};	611	# with AnyEvent::Handle, do them a favour.
203	delete $self->{fh};	612	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
204	}	613	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		614	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
205		615
		616	AnyEvent::fh_unblock $self->{fh};
		617
		618	$self->{_activity} =
		619	$self->{_ractivity} =
		620	$self->{_wactivity} = AE::now;
		621
		622	$self->{read_size} ||= 2048;
		623	$self->{max_read_size} = $self->{read_size}
		624	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		625
		626	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		627	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		628	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		629
		630	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		631	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		632
		633	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		634
		635	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
		636	if $self->{tls};
		637
		638	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
		639
		640	$self->start_read
		641	if $self->{on_read} || @{ $self->{_queue} };
		642
		643	$self->_drain_wbuf;
		644	}
		645
206	sub error {	646	sub _error {
207	my ($self) = @_;	647	my ($self, $errno, $fatal, $message) = @_;
208		648
209	{	649	$! = $errno;
210	local $!;	650	$message ||= "$!";
211	$self->_shutdown;
212	}
213		651
214	if ($self->{on_error}) {	652	if ($self->{on_error}) {
215	$self->{on_error}($self);	653	$self->{on_error}($self, $fatal, $message);
216	} else {	654	$self->destroy if $fatal;
		655	} elsif ($self->{fh} || $self->{connect}) {
		656	$self->destroy;
217	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	657	Carp::croak "AnyEvent::Handle uncaught error: $message";
218	}	658	}
219	}	659	}
220		660
221	=item $fh = $handle->fh	661	=item $fh = $handle->fh
222		662
223	This method returns the file handle of the L<AnyEvent::Handle> object.	663	This method returns the file handle used to create the L<AnyEvent::Handle> object.
224		664
225	=cut	665	=cut
226		666
227	sub fh { $_[0]->{fh} }	667	sub fh { $_[0]{fh} }
228		668
229	=item $handle->on_error ($cb)	669	=item $handle->on_error ($cb)
230		670
231	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	671	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
232		672
…		…
244		684
245	sub on_eof {	685	sub on_eof {
246	$_[0]{on_eof} = $_[1];	686	$_[0]{on_eof} = $_[1];
247	}	687	}
248		688
		689	=item $handle->on_timeout ($cb)
		690
		691	=item $handle->on_rtimeout ($cb)
		692
		693	=item $handle->on_wtimeout ($cb)
		694
		695	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		696	callback, or disables the callback (but not the timeout) if C<$cb> =
		697	C<undef>. See the C<timeout> constructor argument and method.
		698
		699	=cut
		700
		701	# see below
		702
		703	=item $handle->autocork ($boolean)
		704
		705	Enables or disables the current autocork behaviour (see C<autocork>
		706	constructor argument). Changes will only take effect on the next write.
		707
		708	=cut
		709
		710	sub autocork {
		711	$_[0]{autocork} = $_[1];
		712	}
		713
		714	=item $handle->no_delay ($boolean)
		715
		716	Enables or disables the C<no_delay> setting (see constructor argument of
		717	the same name for details).
		718
		719	=cut
		720
		721	sub no_delay {
		722	$_[0]{no_delay} = $_[1];
		723
		724	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		725	if $_[0]{fh};
		726	}
		727
		728	=item $handle->keepalive ($boolean)
		729
		730	Enables or disables the C<keepalive> setting (see constructor argument of
		731	the same name for details).
		732
		733	=cut
		734
		735	sub keepalive {
		736	$_[0]{keepalive} = $_[1];
		737
		738	eval {
		739	local $SIG{__DIE__};
		740	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		741	if $_[0]{fh};
		742	};
		743	}
		744
		745	=item $handle->oobinline ($boolean)
		746
		747	Enables or disables the C<oobinline> setting (see constructor argument of
		748	the same name for details).
		749
		750	=cut
		751
		752	sub oobinline {
		753	$_[0]{oobinline} = $_[1];
		754
		755	eval {
		756	local $SIG{__DIE__};
		757	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		758	if $_[0]{fh};
		759	};
		760	}
		761
		762	=item $handle->keepalive ($boolean)
		763
		764	Enables or disables the C<keepalive> setting (see constructor argument of
		765	the same name for details).
		766
		767	=cut
		768
		769	sub keepalive {
		770	$_[0]{keepalive} = $_[1];
		771
		772	eval {
		773	local $SIG{__DIE__};
		774	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		775	if $_[0]{fh};
		776	};
		777	}
		778
		779	=item $handle->on_starttls ($cb)
		780
		781	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		782
		783	=cut
		784
		785	sub on_starttls {
		786	$_[0]{on_starttls} = $_[1];
		787	}
		788
		789	=item $handle->on_stoptls ($cb)
		790
		791	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		792
		793	=cut
		794
		795	sub on_stoptls {
		796	$_[0]{on_stoptls} = $_[1];
		797	}
		798
		799	=item $handle->rbuf_max ($max_octets)
		800
		801	Configures the C<rbuf_max> setting (C<undef> disables it).
		802
		803	=item $handle->wbuf_max ($max_octets)
		804
		805	Configures the C<wbuf_max> setting (C<undef> disables it).
		806
		807	=cut
		808
		809	sub rbuf_max {
		810	$_[0]{rbuf_max} = $_[1];
		811	}
		812
		813	sub wbuf_max {
		814	$_[0]{wbuf_max} = $_[1];
		815	}
		816
		817	#############################################################################
		818
		819	=item $handle->timeout ($seconds)
		820
		821	=item $handle->rtimeout ($seconds)
		822
		823	=item $handle->wtimeout ($seconds)
		824
		825	Configures (or disables) the inactivity timeout.
		826
		827	The timeout will be checked instantly, so this method might destroy the
		828	handle before it returns.
		829
		830	=item $handle->timeout_reset
		831
		832	=item $handle->rtimeout_reset
		833
		834	=item $handle->wtimeout_reset
		835
		836	Reset the activity timeout, as if data was received or sent.
		837
		838	These methods are cheap to call.
		839
		840	=cut
		841
		842	for my $dir ("", "r", "w") {
		843	my $timeout = "${dir}timeout";
		844	my $tw = "_${dir}tw";
		845	my $on_timeout = "on_${dir}timeout";
		846	my $activity = "_${dir}activity";
		847	my $cb;
		848
		849	*$on_timeout = sub {
		850	$_[0]{$on_timeout} = $_[1];
		851	};
		852
		853	*$timeout = sub {
		854	my ($self, $new_value) = @_;
		855
		856	$new_value >= 0
		857	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		858
		859	$self->{$timeout} = $new_value;
		860	delete $self->{$tw}; &$cb;
		861	};
		862
		863	*{"${dir}timeout_reset"} = sub {
		864	$_[0]{$activity} = AE::now;
		865	};
		866
		867	# main workhorse:
		868	# reset the timeout watcher, as neccessary
		869	# also check for time-outs
		870	$cb = sub {
		871	my ($self) = @_;
		872
		873	if ($self->{$timeout} && $self->{fh}) {
		874	my $NOW = AE::now;
		875
		876	# when would the timeout trigger?
		877	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		878
		879	# now or in the past already?
		880	if ($after <= 0) {
		881	$self->{$activity} = $NOW;
		882
		883	if ($self->{$on_timeout}) {
		884	$self->{$on_timeout}($self);
		885	} else {
		886	$self->_error (Errno::ETIMEDOUT);
		887	}
		888
		889	# callback could have changed timeout value, optimise
		890	return unless $self->{$timeout};
		891
		892	# calculate new after
		893	$after = $self->{$timeout};
		894	}
		895
		896	Scalar::Util::weaken $self;
		897	return unless $self; # ->error could have destroyed $self
		898
		899	$self->{$tw} ||= AE::timer $after, 0, sub {
		900	delete $self->{$tw};
		901	$cb->($self);
		902	};
		903	} else {
		904	delete $self->{$tw};
		905	}
		906	}
		907	}
		908
249	#############################################################################	909	#############################################################################
250		910
251	=back	911	=back
252		912
253	=head2 WRITE QUEUE	913	=head2 WRITE QUEUE
…		…
257		917
258	The write queue is very simple: you can add data to its end, and	918	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.	919	AnyEvent::Handle will automatically try to get rid of it for you.
260		920
261	When data could be written and the write buffer is shorter then the low	921	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.	922	water mark, the C<on_drain> callback will be invoked once.
263		923
264	=over 4	924	=over 4
265		925
266	=item $handle->on_drain ($cb)	926	=item $handle->on_drain ($cb)
267		927
268	Sets the C<on_drain> callback or clears it (see the description of	928	Sets the C<on_drain> callback or clears it (see the description of
269	C<on_drain> in the constructor).	929	C<on_drain> in the constructor).
270		930
		931	This method may invoke callbacks (and therefore the handle might be
		932	destroyed after it returns).
		933
271	=cut	934	=cut
272		935
273	sub on_drain {	936	sub on_drain {
274	my ($self, $cb) = @_;	937	my ($self, $cb) = @_;
275		938
276	$self->{on_drain} = $cb;	939	$self->{on_drain} = $cb;
277		940
278	$cb->($self)	941	$cb->($self)
279	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	942	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
280	}	943	}
281		944
282	=item $handle->push_write ($data)	945	=item $handle->push_write ($data)
283		946
284	Queues the given scalar to be written. You can push as much data as you	947	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>	948	you want (only limited by the available memory and C<wbuf_max>), as
286	buffers it independently of the kernel.	949	C<AnyEvent::Handle> buffers it independently of the kernel.
		950
		951	This method may invoke callbacks (and therefore the handle might be
		952	destroyed after it returns).
287		953
288	=cut	954	=cut
289		955
290	sub _drain_wbuf {	956	sub _drain_wbuf {
291	my ($self) = @_;	957	my ($self) = @_;
292		958
293	if (!$self->{ww} && length $self->{wbuf}) {	959	if (!$self->{_ww} && length $self->{wbuf}) {
		960
294	Scalar::Util::weaken $self;	961	Scalar::Util::weaken $self;
		962
295	my $cb = sub {	963	my $cb = sub {
296	my $len = syswrite $self->{fh}, $self->{wbuf};	964	my $len = syswrite $self->{fh}, $self->{wbuf};
297		965
298	if ($len >= 0) {	966	if (defined $len) {
299	substr $self->{wbuf}, 0, $len, "";	967	substr $self->{wbuf}, 0, $len, "";
300		968
		969	$self->{_activity} = $self->{_wactivity} = AE::now;
		970
301	$self->{on_drain}($self)	971	$self->{on_drain}($self)
302	if $self->{low_water_mark} >= length $self->{wbuf}	972	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
303	&& $self->{on_drain};	973	&& $self->{on_drain};
304		974
305	delete $self->{ww} unless length $self->{wbuf};	975	delete $self->{_ww} unless length $self->{wbuf};
306	} elsif ($! != EAGAIN && $! != EINTR) {	976	} elsif ($! != EAGAIN && $! != EINTR && $! != EWOULDBLOCK && $! != WSAEWOULDBLOCK) {
307	$self->error;	977	$self->_error ($!, 1);
308	}	978	}
309	};	979	};
310		980
311	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	981	# try to write data immediately
		982	$cb->() unless $self->{autocork};
312		983
313	$cb->($self);	984	# if still data left in wbuf, we need to poll
		985	$self->{_ww} = AE::io $self->{fh}, 1, $cb
		986	if length $self->{wbuf};
		987
		988	if (
		989	defined $self->{wbuf_max}
		990	&& $self->{wbuf_max} < length $self->{wbuf}
		991	) {
		992	$self->_error (Errno::ENOSPC, 1), return;
		993	}
314	};	994	};
315	}	995	}
316		996
317	our %WH;	997	our %WH;
318		998
		999	# deprecated
319	sub register_write_type($$) {	1000	sub register_write_type($$) {
320	$WH{$_[0]} = $_[1];	1001	$WH{$_[0]} = $_[1];
321	}	1002	}
322		1003
323	sub push_write {	1004	sub push_write {
324	my $self = shift;	1005	my $self = shift;
325		1006
326	if (@_ > 1) {	1007	if (@_ > 1) {
327	my $type = shift;	1008	my $type = shift;
328		1009
		1010	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
329	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	1011	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
330	->($self, @_);	1012	->($self, @_);
331	}	1013	}
332		1014
		1015	# we downgrade here to avoid hard-to-track-down bugs,
		1016	# and diagnose the problem earlier and better.
		1017
333	if ($self->{filter_w}) {	1018	if ($self->{tls}) {
334	$self->{filter_w}->($self, \$_[0]);	1019	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		1020	&_dotls ($self) if $self->{fh};
335	} else {	1021	} else {
336	$self->{wbuf} .= $_[0];	1022	utf8::downgrade $self->{wbuf} .= $_[0];
337	$self->_drain_wbuf;	1023	$self->_drain_wbuf if $self->{fh};
338	}	1024	}
339	}	1025	}
340		1026
341	=item $handle->push_write (type => @args)	1027	=item $handle->push_write (type => @args)
342		1028
343	=item $handle->unshift_write (type => @args)
344
345	Instead of formatting your data yourself, you can also let this module do	1029	Instead of formatting your data yourself, you can also let this module
346	the job by specifying a type and type-specific arguments.	1030	do the job by specifying a type and type-specific arguments. You
		1031	can also specify the (fully qualified) name of a package, in which
		1032	case AnyEvent tries to load the package and then expects to find the
		1033	C<anyevent_write_type> function inside (see "custom write types", below).
347		1034
348	Predefined types are (if you have ideas for additional types, feel free to	1035	Predefined types are (if you have ideas for additional types, feel free to
349	drop by and tell us):	1036	drop by and tell us):
350		1037
351	=over 4	1038	=over 4
…		…
353	=item netstring => $string	1040	=item netstring => $string
354		1041
355	Formats the given value as netstring	1042	Formats the given value as netstring
356	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	1043	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
357		1044
358	=back
359
360	=cut	1045	=cut
361		1046
362	register_write_type netstring => sub {	1047	register_write_type netstring => sub {
363	my ($self, $string) = @_;	1048	my ($self, $string) = @_;
364		1049
365	sprintf "%d:%s,", (length $string), $string	1050	(length $string) . ":$string,"
366	};	1051	};
367		1052
368	=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args)	1053	=item packstring => $format, $data
369		1054
370	This function (not method) lets you add your own types to C<push_write>.	1055	An octet string prefixed with an encoded length. The encoding C<$format>
		1056	uses the same format as a Perl C<pack> format, but must specify a single
		1057	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1058	optional C<!>, C<< < >> or C<< > >> modifier).
		1059
		1060	=cut
		1061
		1062	register_write_type packstring => sub {
		1063	my ($self, $format, $string) = @_;
		1064
		1065	pack "$format/a*", $string
		1066	};
		1067
		1068	=item json => $array_or_hashref
		1069
		1070	Encodes the given hash or array reference into a JSON object. Unless you
		1071	provide your own JSON object, this means it will be encoded to JSON text
		1072	in UTF-8.
		1073
		1074	The default encoder might or might not handle every type of JSON value -
		1075	it might be limited to arrays and objects for security reasons. See the
		1076	C<json> constructor attribute for more details.
		1077
		1078	JSON objects (and arrays) are self-delimiting, so if you only use arrays
		1079	and hashes, you can write JSON at one end of a handle and read them at the
		1080	other end without using any additional framing.
		1081
		1082	The JSON text generated by the default encoder is guaranteed not to
		1083	contain any newlines: While this module doesn't need delimiters after or
		1084	between JSON texts to be able to read them, many other languages depend on
		1085	them.
		1086
		1087	A simple RPC protocol that interoperates easily with other languages is
		1088	to send JSON arrays (or objects, although arrays are usually the better
		1089	choice as they mimic how function argument passing works) and a newline
		1090	after each JSON text:
		1091
		1092	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		1093	$handle->push_write ("\012");
		1094
		1095	An AnyEvent::Handle receiver would simply use the C<json> read type and
		1096	rely on the fact that the newline will be skipped as leading whitespace:
		1097
		1098	$handle->push_read (json => sub { my $array = $_[1]; ... });
		1099
		1100	Other languages could read single lines terminated by a newline and pass
		1101	this line into their JSON decoder of choice.
		1102
		1103	=item cbor => $perl_scalar
		1104
		1105	Encodes the given scalar into a CBOR value. Unless you provide your own
		1106	L<CBOR::XS> object, this means it will be encoded to a CBOR string not
		1107	using any extensions, if possible.
		1108
		1109	CBOR values are self-delimiting, so you can write CBOR at one end of
		1110	a handle and read them at the other end without using any additional
		1111	framing.
		1112
		1113	A simple nd very very fast RPC protocol that interoperates with
		1114	other languages is to send CBOR and receive CBOR values (arrays are
		1115	recommended):
		1116
		1117	$handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
		1118
		1119	An AnyEvent::Handle receiver would simply use the C<cbor> read type:
		1120
		1121	$handle->push_read (cbor => sub { my $array = $_[1]; ... });
		1122
		1123	=cut
		1124
		1125	sub json_coder() {
		1126	eval { require JSON::XS; JSON::XS->new->utf8 }
		1127	|| do { require JSON::PP; JSON::PP->new->utf8 }
		1128	}
		1129
		1130	register_write_type json => sub {
		1131	my ($self, $ref) = @_;
		1132
		1133	($self->{json} ||= json_coder)
		1134	->encode ($ref)
		1135	};
		1136
		1137	sub cbor_coder() {
		1138	require CBOR::XS;
		1139	CBOR::XS->new
		1140	}
		1141
		1142	register_write_type cbor => sub {
		1143	my ($self, $scalar) = @_;
		1144
		1145	($self->{cbor} ||= cbor_coder)
		1146	->encode ($scalar)
		1147	};
		1148
		1149	=item storable => $reference
		1150
		1151	Freezes the given reference using L<Storable> and writes it to the
		1152	handle. Uses the C<nfreeze> format.
		1153
		1154	=cut
		1155
		1156	register_write_type storable => sub {
		1157	my ($self, $ref) = @_;
		1158
		1159	require Storable unless $Storable::VERSION;
		1160
		1161	pack "w/a*", Storable::nfreeze ($ref)
		1162	};
		1163
		1164	=back
		1165
		1166	=item $handle->push_shutdown
		1167
		1168	Sometimes you know you want to close the socket after writing your data
		1169	before it was actually written. One way to do that is to replace your
		1170	C<on_drain> handler by a callback that shuts down the socket (and set
		1171	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1172	replaces the C<on_drain> callback with:
		1173
		1174	sub { shutdown $_[0]{fh}, 1 }
		1175
		1176	This simply shuts down the write side and signals an EOF condition to the
		1177	the peer.
		1178
		1179	You can rely on the normal read queue and C<on_eof> handling
		1180	afterwards. This is the cleanest way to close a connection.
		1181
		1182	This method may invoke callbacks (and therefore the handle might be
		1183	destroyed after it returns).
		1184
		1185	=cut
		1186
		1187	sub push_shutdown {
		1188	my ($self) = @_;
		1189
		1190	delete $self->{low_water_mark};
		1191	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1192	}
		1193
		1194	=item custom write types - Package::anyevent_write_type $handle, @args
		1195
		1196	Instead of one of the predefined types, you can also specify the name of
		1197	a package. AnyEvent will try to load the package and then expects to find
		1198	a function named C<anyevent_write_type> inside. If it isn't found, it
		1199	progressively tries to load the parent package until it either finds the
		1200	function (good) or runs out of packages (bad).
		1201
371	Whenever the given C<type> is used, C<push_write> will invoke the code	1202	Whenever the given C<type> is used, C<push_write> will the function with
372	reference with the handle object and the remaining arguments.	1203	the handle object and the remaining arguments.
373		1204
374	The code reference is supposed to return a single octet string that will	1205	The function is supposed to return a single octet string that will be
375	be appended to the write buffer.	1206	appended to the write buffer, so you can mentally treat this function as a
		1207	"arguments to on-the-wire-format" converter.
376		1208
377	Note that this is a function, and all types registered this way will be	1209	Example: implement a custom write type C<join> that joins the remaining
378	global, so try to use unique names.	1210	arguments using the first one.
		1211
		1212	$handle->push_write (My::Type => " ", 1,2,3);
		1213
		1214	# uses the following package, which can be defined in the "My::Type" or in
		1215	# the "My" modules to be auto-loaded, or just about anywhere when the
		1216	# My::Type::anyevent_write_type is defined before invoking it.
		1217
		1218	package My::Type;
		1219
		1220	sub anyevent_write_type {
		1221	my ($handle, $delim, @args) = @_;
		1222
		1223	join $delim, @args
		1224	}
379		1225
380	=cut	1226	=cut
381		1227
382	#############################################################################	1228	#############################################################################
383		1229
…		…
392	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1238	ways, the "simple" way, using only C<on_read> and the "complex" way, using
393	a queue.	1239	a queue.
394		1240
395	In the simple case, you just install an C<on_read> callback and whenever	1241	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	1242	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	1243	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
398	or not.	1244	leave the data there if you want to accumulate more (e.g. when only a
		1245	partial message has been received so far), or change the read queue with
		1246	e.g. C<push_read>.
399		1247
400	In the more complex case, you want to queue multiple callbacks. In this	1248	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	1249	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>,	1250	data arrives (also the first time it is queued) and remove it when it has
403	below).	1251	done its job (see C<push_read>, below).
404		1252
405	This way you can, for example, push three line-reads, followed by reading	1253	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.	1254	a chunk of data, and AnyEvent::Handle will execute them in order.
407		1255
408	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	1256	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
409	the specified number of bytes which give an XML datagram.	1257	the specified number of bytes which give an XML datagram.
410		1258
411	# in the default state, expect some header bytes	1259	# in the default state, expect some header bytes
412	$handle->on_read (sub {	1260	$handle->on_read (sub {
413	# some data is here, now queue the length-header-read (4 octets)	1261	# some data is here, now queue the length-header-read (4 octets)
414	shift->unshift_read_chunk (4, sub {	1262	shift->unshift_read (chunk => 4, sub {
415	# header arrived, decode	1263	# header arrived, decode
416	my $len = unpack "N", $_[1];	1264	my $len = unpack "N", $_[1];
417		1265
418	# now read the payload	1266	# now read the payload
419	shift->unshift_read_chunk ($len, sub {	1267	shift->unshift_read (chunk => $len, sub {
420	my $xml = $_[1];	1268	my $xml = $_[1];
421	# handle xml	1269	# handle xml
422	});	1270	});
423	});	1271	});
424	});	1272	});
425		1273
426	Example 2: Implement a client for a protocol that replies either with	1274	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	1275	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	1276	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	1277	just pipeline sending both requests and manipulate the queue as necessary
430	the callbacks:	1278	in the callbacks.
431		1279
432	# request one	1280	When the first callback is called and sees an "OK" response, it will
		1281	C<unshift> another line-read. This line-read will be queued I<before> the
		1282	64-byte chunk callback.
		1283
		1284	# request one, returns either "OK + extra line" or "ERROR"
433	$handle->push_write ("request 1\015\012");	1285	$handle->push_write ("request 1\015\012");
434		1286
435	# we expect "ERROR" or "OK" as response, so push a line read	1287	# we expect "ERROR" or "OK" as response, so push a line read
436	$handle->push_read_line (sub {	1288	$handle->push_read (line => sub {
437	# if we got an "OK", we have to _prepend_ another line,	1289	# if we got an "OK", we have to _prepend_ another line,
438	# so it will be read before the second request reads its 64 bytes	1290	# so it will be read before the second request reads its 64 bytes
439	# which are already in the queue when this callback is called	1291	# which are already in the queue when this callback is called
440	# we don't do this in case we got an error	1292	# we don't do this in case we got an error
441	if ($_[1] eq "OK") {	1293	if ($_[1] eq "OK") {
442	$_[0]->unshift_read_line (sub {	1294	$_[0]->unshift_read (line => sub {
443	my $response = $_[1];	1295	my $response = $_[1];
444	...	1296	...
445	});	1297	});
446	}	1298	}
447	});	1299	});
448		1300
449	# request two	1301	# request two, simply returns 64 octets
450	$handle->push_write ("request 2\015\012");	1302	$handle->push_write ("request 2\015\012");
451		1303
452	# simply read 64 bytes, always	1304	# simply read 64 bytes, always
453	$handle->push_read_chunk (64, sub {	1305	$handle->push_read (chunk => 64, sub {
454	my $response = $_[1];	1306	my $response = $_[1];
455	...	1307	...
456	});	1308	});
457		1309
458	=over 4	1310	=over 4
459		1311
460	=cut	1312	=cut
461		1313
462	sub _drain_rbuf {	1314	sub _drain_rbuf {
463	my ($self) = @_;	1315	my ($self) = @_;
		1316
		1317	# avoid recursion
		1318	return if $self->{_skip_drain_rbuf};
		1319	local $self->{_skip_drain_rbuf} = 1;
		1320
		1321	while () {
		1322	# we need to use a separate tls read buffer, as we must not receive data while
		1323	# we are draining the buffer, and this can only happen with TLS.
		1324	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1325	if exists $self->{_tls_rbuf};
		1326
		1327	my $len = length $self->{rbuf};
		1328
		1329	if (my $cb = shift @{ $self->{_queue} }) {
		1330	unless ($cb->($self)) {
		1331	# no progress can be made
		1332	# (not enough data and no data forthcoming)
		1333	$self->_error (Errno::EPIPE, 1), return
		1334	if $self->{_eof};
		1335
		1336	unshift @{ $self->{_queue} }, $cb;
		1337	last;
		1338	}
		1339	} elsif ($self->{on_read}) {
		1340	last unless $len;
		1341
		1342	$self->{on_read}($self);
		1343
		1344	if (
		1345	$len == length $self->{rbuf} # if no data has been consumed
		1346	&& !@{ $self->{_queue} } # and the queue is still empty
		1347	&& $self->{on_read} # but we still have on_read
		1348	) {
		1349	# no further data will arrive
		1350	# so no progress can be made
		1351	$self->_error (Errno::EPIPE, 1), return
		1352	if $self->{_eof};
		1353
		1354	last; # more data might arrive
		1355	}
		1356	} else {
		1357	# read side becomes idle
		1358	delete $self->{_rw} unless $self->{tls};
		1359	last;
		1360	}
		1361	}
		1362
		1363	if ($self->{_eof}) {
		1364	$self->{on_eof}
		1365	? $self->{on_eof}($self)
		1366	: $self->_error (0, 1, "Unexpected end-of-file");
		1367
		1368	return;
		1369	}
464		1370
465	if (	1371	if (
466	defined $self->{rbuf_max}	1372	defined $self->{rbuf_max}
467	&& $self->{rbuf_max} < length $self->{rbuf}	1373	&& $self->{rbuf_max} < length $self->{rbuf}
468	) {	1374	) {
469	$! = &Errno::ENOSPC; return $self->error;	1375	$self->_error (Errno::ENOSPC, 1), return;
470	}	1376	}
471		1377
472	return if $self->{in_drain};	1378	# may need to restart read watcher
473	local $self->{in_drain} = 1;	1379	unless ($self->{_rw}) {
474		1380	$self->start_read
475	while (my $len = length $self->{rbuf}) {	1381	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	}	1382	}
511	}	1383	}
512		1384
513	=item $handle->on_read ($cb)	1385	=item $handle->on_read ($cb)
514		1386
515	This replaces the currently set C<on_read> callback, or clears it (when	1387	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	1388	the new callback is C<undef>). See the description of C<on_read> in the
517	constructor.	1389	constructor.
518		1390
		1391	This method may invoke callbacks (and therefore the handle might be
		1392	destroyed after it returns).
		1393
519	=cut	1394	=cut
520		1395
521	sub on_read {	1396	sub on_read {
522	my ($self, $cb) = @_;	1397	my ($self, $cb) = @_;
523		1398
524	$self->{on_read} = $cb;	1399	$self->{on_read} = $cb;
		1400	$self->_drain_rbuf if $cb;
525	}	1401	}
526		1402
527	=item $handle->rbuf	1403	=item $handle->rbuf
528		1404
529	Returns the read buffer (as a modifiable lvalue).	1405	Returns the read buffer (as a modifiable lvalue). You can also access the
		1406	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1407	much faster, and no less clean).
530		1408
531	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1409	The only operation allowed on the read buffer (apart from looking at it)
532	you want.	1410	is removing data from its beginning. Otherwise modifying or appending to
		1411	it is not allowed and will lead to hard-to-track-down bugs.
533		1412
534	NOTE: The read buffer should only be used or modified if the C<on_read>,	1413	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	1414	callback or when C<push_read> or C<unshift_read> are used with a single
536	automatically manage the read buffer.	1415	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1416	will manage the read buffer on their own.
537		1417
538	=cut	1418	=cut
539		1419
540	sub rbuf : lvalue {	1420	sub rbuf : lvalue {
541	$_[0]{rbuf}	1421	$_[0]{rbuf}
…		…
558		1438
559	If enough data was available, then the callback must remove all data it is	1439	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	1440	interested in (which can be none at all) and return a true value. After returning
561	true, it will be removed from the queue.	1441	true, it will be removed from the queue.
562		1442
		1443	These methods may invoke callbacks (and therefore the handle might be
		1444	destroyed after it returns).
		1445
563	=cut	1446	=cut
564		1447
565	our %RH;	1448	our %RH;
566		1449
567	sub register_read_type($$) {	1450	sub register_read_type($$) {
…		…
573	my $cb = pop;	1456	my $cb = pop;
574		1457
575	if (@_) {	1458	if (@_) {
576	my $type = shift;	1459	my $type = shift;
577		1460
		1461	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
578	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1462	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
579	->($self, $cb, @_);	1463	->($self, $cb, @_);
580	}	1464	}
581		1465
582	push @{ $self->{queue} }, $cb;	1466	push @{ $self->{_queue} }, $cb;
583	$self->_drain_rbuf;	1467	$self->_drain_rbuf;
584	}	1468	}
585		1469
586	sub unshift_read {	1470	sub unshift_read {
587	my $self = shift;	1471	my $self = shift;
588	my $cb = pop;	1472	my $cb = pop;
589		1473
590	if (@_) {	1474	if (@_) {
591	my $type = shift;	1475	my $type = shift;
592		1476
		1477	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
593	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1478	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
594	->($self, $cb, @_);	1479	->($self, $cb, @_);
595	}	1480	}
596		1481
597
598	unshift @{ $self->{queue} }, $cb;	1482	unshift @{ $self->{_queue} }, $cb;
599	$self->_drain_rbuf;	1483	$self->_drain_rbuf;
600	}	1484	}
601		1485
602	=item $handle->push_read (type => @args, $cb)	1486	=item $handle->push_read (type => @args, $cb)
603		1487
604	=item $handle->unshift_read (type => @args, $cb)	1488	=item $handle->unshift_read (type => @args, $cb)
605		1489
606	Instead of providing a callback that parses the data itself you can chose	1490	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	1491	between a number of predefined parsing formats, for chunks of data, lines
608	etc.	1492	etc. You can also specify the (fully qualified) name of a package, in
		1493	which case AnyEvent tries to load the package and then expects to find the
		1494	C<anyevent_read_type> function inside (see "custom read types", below).
609		1495
610	Predefined types are (if you have ideas for additional types, feel free to	1496	Predefined types are (if you have ideas for additional types, feel free to
611	drop by and tell us):	1497	drop by and tell us):
612		1498
613	=over 4	1499	=over 4
614		1500
615	=item chunk => $octets, $cb->($self, $data)	1501	=item chunk => $octets, $cb->($handle, $data)
616		1502
617	Invoke the callback only once C<$octets> bytes have been read. Pass the	1503	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	1504	data read to the callback. The callback will never be called with less
619	data.	1505	data.
620		1506
621	Example: read 2 bytes.	1507	Example: read 2 bytes.
622		1508
623	$handle->push_read (chunk => 2, sub {	1509	$handle->push_read (chunk => 2, sub {
624	warn "yay ", unpack "H*", $_[1];	1510	say "yay " . unpack "H*", $_[1];
625	});	1511	});
626		1512
627	=cut	1513	=cut
628		1514
629	register_read_type chunk => sub {	1515	register_read_type chunk => sub {
…		…
634	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1520	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
635	1	1521	1
636	}	1522	}
637	};	1523	};
638		1524
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, $eol)	1525	=item line => [$eol, ]$cb->($handle, $line, $eol)
649		1526
650	The callback will be called only once a full line (including the end of	1527	The callback will be called only once a full line (including the end of
651	line marker, C<$eol>) has been read. This line (excluding the end of line	1528	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	1529	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>).	1530	the end of line marker as the third argument (C<$eol>).
…		…
667	=cut	1544	=cut
668		1545
669	register_read_type line => sub {	1546	register_read_type line => sub {
670	my ($self, $cb, $eol) = @_;	1547	my ($self, $cb, $eol) = @_;
671		1548
672	$eol = qr|(\015?\012)| if @_ < 3;	1549	if (@_ < 3) {
		1550	# this is faster then the generic code below
		1551	sub {
		1552	(my $pos = index $_[0]{rbuf}, "\012") >= 0
		1553	or return;
		1554
		1555	(my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
		1556	$cb->($_[0], $str, "$1");
		1557	1
		1558	}
		1559	} else {
673	$eol = quotemeta $eol unless ref $eol;	1560	$eol = quotemeta $eol unless ref $eol;
674	$eol = qr|^(.*?)($eol)|s;	1561	$eol = qr|^(.*?)($eol)|s;
		1562
		1563	sub {
		1564	$_[0]{rbuf} =~ s/$eol// or return;
		1565
		1566	$cb->($_[0], "$1", "$2");
		1567	1
		1568	}
		1569	}
		1570	};
		1571
		1572	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1573
		1574	Makes a regex match against the regex object C<$accept> and returns
		1575	everything up to and including the match. All the usual regex variables
		1576	($1, %+ etc.) from the regex match are available in the callback.
		1577
		1578	Example: read a single line terminated by '\n'.
		1579
		1580	$handle->push_read (regex => qr<\n>, sub { ... });
		1581
		1582	If C<$reject> is given and not undef, then it determines when the data is
		1583	to be rejected: it is matched against the data when the C<$accept> regex
		1584	does not match and generates an C<EBADMSG> error when it matches. This is
		1585	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1586	receive buffer overflow).
		1587
		1588	Example: expect a single decimal number followed by whitespace, reject
		1589	anything else (not the use of an anchor).
		1590
		1591	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1592
		1593	If C<$skip> is given and not C<undef>, then it will be matched against
		1594	the receive buffer when neither C<$accept> nor C<$reject> match,
		1595	and everything preceding and including the match will be accepted
		1596	unconditionally. This is useful to skip large amounts of data that you
		1597	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1598	have to start matching from the beginning. This is purely an optimisation
		1599	and is usually worth it only when you expect more than a few kilobytes.
		1600
		1601	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1602	expect the header to be very large (it isn't in practice, but...), we use
		1603	a skip regex to skip initial portions. The skip regex is tricky in that
		1604	it only accepts something not ending in either \015 or \012, as these are
		1605	required for the accept regex.
		1606
		1607	$handle->push_read (regex =>
		1608	qr<\015\012\015\012>,
		1609	undef, # no reject
		1610	qr<^.*[^\015\012]>,
		1611	sub { ... });
		1612
		1613	=cut
		1614
		1615	register_read_type regex => sub {
		1616	my ($self, $cb, $accept, $reject, $skip) = @_;
		1617
		1618	my $data;
		1619	my $rbuf = \$self->{rbuf};
675		1620
676	sub {	1621	sub {
677	$_[0]{rbuf} =~ s/$eol// or return;	1622	# accept
678		1623	if ($$rbuf =~ $accept) {
		1624	$data .= substr $$rbuf, 0, $+[0], "";
679	$cb->($_[0], $1, $2);	1625	$cb->($_[0], $data);
		1626	return 1;
		1627	}
680	1	1628
		1629	# reject
		1630	if ($reject && $$rbuf =~ $reject) {
		1631	$_[0]->_error (Errno::EBADMSG);
		1632	}
		1633
		1634	# skip
		1635	if ($skip && $$rbuf =~ $skip) {
		1636	$data .= substr $$rbuf, 0, $+[0], "";
		1637	}
		1638
		1639	()
681	}	1640	}
682	};	1641	};
683		1642
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)	1643	=item netstring => $cb->($handle, $string)
696		1644
697	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).	1645	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
698		1646
699	Throws an error with C<$!> set to EBADMSG on format violations.	1647	Throws an error with C<$!> set to EBADMSG on format violations.
700		1648
…		…
704	my ($self, $cb) = @_;	1652	my ($self, $cb) = @_;
705		1653
706	sub {	1654	sub {
707	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1655	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
708	if ($_[0]{rbuf} =~ /[^0-9]/) {	1656	if ($_[0]{rbuf} =~ /[^0-9]/) {
709	$! = &Errno::EBADMSG;	1657	$_[0]->_error (Errno::EBADMSG);
710	$self->error;
711	}	1658	}
712	return;	1659	return;
713	}	1660	}
714		1661
715	my $len = $1;	1662	my $len = $1;
716		1663
717	$self->unshift_read (chunk => $len, sub {	1664	$_[0]->unshift_read (chunk => $len, sub {
718	my $string = $_[1];	1665	my $string = $_[1];
719	$_[0]->unshift_read (chunk => 1, sub {	1666	$_[0]->unshift_read (chunk => 1, sub {
720	if ($_[1] eq ",") {	1667	if ($_[1] eq ",") {
721	$cb->($_[0], $string);	1668	$cb->($_[0], $string);
722	} else {	1669	} else {
723	$! = &Errno::EBADMSG;	1670	$_[0]->_error (Errno::EBADMSG);
724	$self->error;
725	}	1671	}
726	});	1672	});
727	});	1673	});
728		1674
729	1	1675	1
730	}	1676	}
731	};	1677	};
732		1678
		1679	=item packstring => $format, $cb->($handle, $string)
		1680
		1681	An octet string prefixed with an encoded length. The encoding C<$format>
		1682	uses the same format as a Perl C<pack> format, but must specify a single
		1683	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1684	optional C<!>, C<< < >> or C<< > >> modifier).
		1685
		1686	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1687	EPP uses a prefix of C<N> (4 octtes).
		1688
		1689	Example: read a block of data prefixed by its length in BER-encoded
		1690	format (very efficient).
		1691
		1692	$handle->push_read (packstring => "w", sub {
		1693	my ($handle, $data) = @_;
		1694	});
		1695
		1696	=cut
		1697
		1698	register_read_type packstring => sub {
		1699	my ($self, $cb, $format) = @_;
		1700
		1701	sub {
		1702	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1703	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1704	or return;
		1705
		1706	$format = length pack $format, $len;
		1707
		1708	# bypass unshift if we already have the remaining chunk
		1709	if ($format + $len <= length $_[0]{rbuf}) {
		1710	my $data = substr $_[0]{rbuf}, $format, $len;
		1711	substr $_[0]{rbuf}, 0, $format + $len, "";
		1712	$cb->($_[0], $data);
		1713	} else {
		1714	# remove prefix
		1715	substr $_[0]{rbuf}, 0, $format, "";
		1716
		1717	# read remaining chunk
		1718	$_[0]->unshift_read (chunk => $len, $cb);
		1719	}
		1720
		1721	1
		1722	}
		1723	};
		1724
		1725	=item json => $cb->($handle, $hash_or_arrayref)
		1726
		1727	Reads a JSON object or array, decodes it and passes it to the
		1728	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1729
		1730	If a C<json> object was passed to the constructor, then that will be
		1731	used for the final decode, otherwise it will create a L<JSON::XS> or
		1732	L<JSON::PP> coder object expecting UTF-8.
		1733
		1734	This read type uses the incremental parser available with JSON version
		1735	2.09 (and JSON::XS version 2.2) and above.
		1736
		1737	Since JSON texts are fully self-delimiting, the C<json> read and write
		1738	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1739	the C<json> write type description, above, for an actual example.
		1740
		1741	=cut
		1742
		1743	register_read_type json => sub {
		1744	my ($self, $cb) = @_;
		1745
		1746	my $json = $self->{json} ||= json_coder;
		1747
		1748	my $data;
		1749
		1750	sub {
		1751	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
		1752
		1753	if ($ref) {
		1754	$_[0]{rbuf} = $json->incr_text;
		1755	$json->incr_text = "";
		1756	$cb->($_[0], $ref);
		1757
		1758	1
		1759	} elsif ($@) {
		1760	# error case
		1761	$json->incr_skip;
		1762
		1763	$_[0]{rbuf} = $json->incr_text;
		1764	$json->incr_text = "";
		1765
		1766	$_[0]->_error (Errno::EBADMSG);
		1767
		1768	()
		1769	} else {
		1770	$_[0]{rbuf} = "";
		1771
		1772	()
		1773	}
		1774	}
		1775	};
		1776
		1777	=item cbor => $cb->($handle, $scalar)
		1778
		1779	Reads a CBOR value, decodes it and passes it to the callback. When a parse
		1780	error occurs, an C<EBADMSG> error will be raised.
		1781
		1782	If a L<CBOR::XS> object was passed to the constructor, then that will be
		1783	used for the final decode, otherwise it will create a CBOR coder without
		1784	enabling any options.
		1785
		1786	You have to provide a dependency to L<CBOR::XS> on your own: this module
		1787	will load the L<CBOR::XS> module, but AnyEvent does not depend on it
		1788	itself.
		1789
		1790	Since CBOR values are fully self-delimiting, the C<cbor> read and write
		1791	types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
		1792	the C<cbor> write type description, above, for an actual example.
		1793
		1794	=cut
		1795
		1796	register_read_type cbor => sub {
		1797	my ($self, $cb) = @_;
		1798
		1799	my $cbor = $self->{cbor} ||= cbor_coder;
		1800
		1801	my $data;
		1802
		1803	sub {
		1804	my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
		1805
		1806	if (@value) {
		1807	$cb->($_[0], @value);
		1808
		1809	1
		1810	} elsif ($@) {
		1811	# error case
		1812	$cbor->incr_reset;
		1813
		1814	$_[0]->_error (Errno::EBADMSG);
		1815
		1816	()
		1817	} else {
		1818	()
		1819	}
		1820	}
		1821	};
		1822
		1823	=item storable => $cb->($handle, $ref)
		1824
		1825	Deserialises a L<Storable> frozen representation as written by the
		1826	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1827	data).
		1828
		1829	Raises C<EBADMSG> error if the data could not be decoded.
		1830
		1831	=cut
		1832
		1833	register_read_type storable => sub {
		1834	my ($self, $cb) = @_;
		1835
		1836	require Storable unless $Storable::VERSION;
		1837
		1838	sub {
		1839	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1840	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1841	or return;
		1842
		1843	my $format = length pack "w", $len;
		1844
		1845	# bypass unshift if we already have the remaining chunk
		1846	if ($format + $len <= length $_[0]{rbuf}) {
		1847	my $data = substr $_[0]{rbuf}, $format, $len;
		1848	substr $_[0]{rbuf}, 0, $format + $len, "";
		1849
		1850	eval { $cb->($_[0], Storable::thaw ($data)); 1 }
		1851	or return $_[0]->_error (Errno::EBADMSG);
		1852	} else {
		1853	# remove prefix
		1854	substr $_[0]{rbuf}, 0, $format, "";
		1855
		1856	# read remaining chunk
		1857	$_[0]->unshift_read (chunk => $len, sub {
		1858	eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
		1859	or $_[0]->_error (Errno::EBADMSG);
		1860	});
		1861	}
		1862
		1863	1
		1864	}
		1865	};
		1866
		1867	=item tls_detect => $cb->($handle, $detect, $major, $minor)
		1868
		1869	Checks the input stream for a valid SSL or TLS handshake TLSPaintext
		1870	record without consuming anything. Only SSL version 3 or higher
		1871	is handled, up to the fictituous protocol 4.x (but both SSL3+ and
		1872	SSL2-compatible framing is supported).
		1873
		1874	If it detects that the input data is likely TLS, it calls the callback
		1875	with a true value for C<$detect> and the (on-wire) TLS version as second
		1876	and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
		1877	3.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
		1878	be definitely not TLS, it calls the callback with a false value for
		1879	C<$detect>.
		1880
		1881	The callback could use this information to decide whether or not to start
		1882	TLS negotiation.
		1883
		1884	In all cases the data read so far is passed to the following read
		1885	handlers.
		1886
		1887	Usually you want to use the C<tls_autostart> read type instead.
		1888
		1889	If you want to design a protocol that works in the presence of TLS
		1890	dtection, make sure that any non-TLS data doesn't start with the octet 22
		1891	(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
		1892	read type does are a bit more strict, but might losen in the future to
		1893	accomodate protocol changes.
		1894
		1895	This read type does not rely on L<AnyEvent::TLS> (and thus, not on
		1896	L<Net::SSLeay>).
		1897
		1898	=item tls_autostart => $tls[, $tls_ctx]
		1899
		1900	Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
		1901	to start tls by calling C<starttls> with the given arguments.
		1902
		1903	In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
		1904	been configured to accept, as servers do not normally send a handshake on
		1905	their own and ths cannot be detected in this way.
		1906
		1907	See C<tls_detect> above for more details.
		1908
		1909	Example: give the client a chance to start TLS before accepting a text
		1910	line.
		1911
		1912	$hdl->push_read (tls_detect => "accept");
		1913	$hdl->push_read (line => sub {
		1914	print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
		1915	});
		1916
		1917	=cut
		1918
		1919	register_read_type tls_detect => sub {
		1920	my ($self, $cb) = @_;
		1921
		1922	sub {
		1923	# this regex matches a full or partial tls record
		1924	if (
		1925	# ssl3+: type(22=handshake) major(=3) minor(any) length_hi
		1926	$self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
		1927	# ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
		1928	or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
		1929	) {
		1930	return if 3 != length $1; # partial match, can't decide yet
		1931
		1932	# full match, valid TLS record
		1933	my ($major, $minor) = unpack "CC", $1;
		1934	$cb->($self, "accept", $major + $minor * 0.1);
		1935	} else {
		1936	# mismatch == guaranteed not TLS
		1937	$cb->($self, undef);
		1938	}
		1939
		1940	1
		1941	}
		1942	};
		1943
		1944	register_read_type tls_autostart => sub {
		1945	my ($self, @tls) = @_;
		1946
		1947	$RH{tls_detect}($self, sub {
		1948	return unless $_[1];
		1949	$_[0]->starttls (@tls);
		1950	})
		1951	};
		1952
733	=back	1953	=back
734		1954
735	=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args)	1955	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
736		1956
737	This function (not method) lets you add your own types to C<push_read>.	1957	Instead of one of the predefined types, you can also specify the name
		1958	of a package. AnyEvent will try to load the package and then expects to
		1959	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1960	progressively tries to load the parent package until it either finds the
		1961	function (good) or runs out of packages (bad).
738		1962
739	Whenever the given C<type> is used, C<push_read> will invoke the code	1963	Whenever this type is used, C<push_read> will invoke the function with the
740	reference with the handle object, the callback and the remaining	1964	handle object, the original callback and the remaining arguments.
741	arguments.
742		1965
743	The code reference is supposed to return a callback (usually a closure)	1966	The function is supposed to return a callback (usually a closure) that
744	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1967	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1968	mentally treat the function as a "configurable read type to read callback"
		1969	converter.
745		1970
746	It should invoke the passed callback when it is done reading (remember to	1971	It should invoke the original callback when it is done reading (remember
747	pass C<$self> as first argument as all other callbacks do that).	1972	to pass C<$handle> as first argument as all other callbacks do that,
		1973	although there is no strict requirement on this).
748		1974
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>,	1975	For examples, see the source of this module (F<perldoc -m
753	search for C<register_read_type>)).	1976	AnyEvent::Handle>, search for C<register_read_type>)).
754		1977
755	=item $handle->stop_read	1978	=item $handle->stop_read
756		1979
757	=item $handle->start_read	1980	=item $handle->start_read
758		1981
759	In rare cases you actually do not want to read anything from the	1982	In rare cases you actually do not want to read anything from the
760	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1983	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
761	any queued callbacks will be executed then. To start reading again, call	1984	any queued callbacks will be executed then. To start reading again, call
762	C<start_read>.	1985	C<start_read>.
763		1986
		1987	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1988	you change the C<on_read> callback or push/unshift a read callback, and it
		1989	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1990	there are any read requests in the queue.
		1991
		1992	In older versions of this module (<= 5.3), these methods had no effect,
		1993	as TLS does not support half-duplex connections. In current versions they
		1994	work as expected, as this behaviour is required to avoid certain resource
		1995	attacks, where the program would be forced to read (and buffer) arbitrary
		1996	amounts of data before being able to send some data. The drawback is that
		1997	some readings of the the SSL/TLS specifications basically require this
		1998	attack to be working, as SSL/TLS implementations might stall sending data
		1999	during a rehandshake.
		2000
		2001	As a guideline, during the initial handshake, you should not stop reading,
		2002	and as a client, it might cause problems, depending on your application.
		2003
764	=cut	2004	=cut
765		2005
766	sub stop_read {	2006	sub stop_read {
767	my ($self) = @_;	2007	my ($self) = @_;
768		2008
769	delete $self->{rw};	2009	delete $self->{_rw};
770	}	2010	}
771		2011
772	sub start_read {	2012	sub start_read {
773	my ($self) = @_;	2013	my ($self) = @_;
774		2014
775	unless ($self->{rw} || $self->{eof}) {	2015	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
776	Scalar::Util::weaken $self;	2016	Scalar::Util::weaken $self;
777		2017
778	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	2018	$self->{_rw} = AE::io $self->{fh}, 0, sub {
779	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	2019	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
780	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	2020	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
781		2021
782	if ($len > 0) {	2022	if ($len > 0) {
783	$self->{filter_r}	2023	$self->{_activity} = $self->{_ractivity} = AE::now;
784	? $self->{filter_r}->($self, $rbuf)	2024
		2025	if ($self->{tls}) {
		2026	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		2027
		2028	&_dotls ($self);
		2029	} else {
785	: $self->_drain_rbuf;	2030	$self->_drain_rbuf;
		2031	}
		2032
		2033	if ($len == $self->{read_size}) {
		2034	$self->{read_size} *= 2;
		2035	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		2036	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		2037	}
786		2038
787	} elsif (defined $len) {	2039	} elsif (defined $len) {
788	delete $self->{rw};	2040	delete $self->{_rw};
789	$self->{eof} = 1;	2041	$self->{_eof} = 1;
790	$self->_drain_rbuf;	2042	$self->_drain_rbuf;
791		2043
792	} elsif ($! != EAGAIN && $! != EINTR) {	2044	} elsif ($! != EAGAIN && $! != EINTR && $! != EWOULDBLOCK && $! != WSAEWOULDBLOCK) {
793	return $self->error;	2045	return $self->_error ($!, 1);
794	}	2046	}
795	});	2047	};
796	}	2048	}
797	}	2049	}
798		2050
		2051	our $ERROR_SYSCALL;
		2052	our $ERROR_WANT_READ;
		2053
		2054	sub _tls_error {
		2055	my ($self, $err) = @_;
		2056
		2057	return $self->_error ($!, 1)
		2058	if $err == Net::SSLeay::ERROR_SYSCALL ();
		2059
		2060	my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		2061
		2062	# reduce error string to look less scary
		2063	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		2064
		2065	if ($self->{_on_starttls}) {
		2066	(delete $self->{_on_starttls})->($self, undef, $err);
		2067	&_freetls;
		2068	} else {
		2069	&_freetls;
		2070	$self->_error (Errno::EPROTO, 1, $err);
		2071	}
		2072	}
		2073
		2074	# poll the write BIO and send the data if applicable
		2075	# also decode read data if possible
		2076	# this is basiclaly our TLS state machine
		2077	# more efficient implementations are possible with openssl,
		2078	# but not with the buggy and incomplete Net::SSLeay.
799	sub _dotls {	2079	sub _dotls {
800	my ($self) = @_;	2080	my ($self) = @_;
801		2081
		2082	my $tmp;
		2083
802	if (length $self->{tls_wbuf}) {	2084	while (length $self->{_tls_wbuf}) {
803	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf})) > 0) {	2085	if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
804	substr $self->{tls_wbuf}, 0, $len, "";	2086	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		2087
		2088	return $self->_tls_error ($tmp)
		2089	if $tmp != $ERROR_WANT_READ
		2090	&& ($tmp != $ERROR_SYSCALL || $!);
		2091
		2092	last;
805	}	2093	}
806	}
807		2094
		2095	substr $self->{_tls_wbuf}, 0, $tmp, "";
		2096	}
		2097
808	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) {	2098	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		2099	unless (length $tmp) {
		2100	$self->{_on_starttls}
		2101	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		2102	&_freetls;
		2103
		2104	if ($self->{on_stoptls}) {
		2105	$self->{on_stoptls}($self);
		2106	return;
		2107	} else {
		2108	# let's treat SSL-eof as we treat normal EOF
		2109	delete $self->{_rw};
		2110	$self->{_eof} = 1;
		2111	}
		2112	}
		2113
		2114	$self->{_tls_rbuf} .= $tmp;
		2115	$self->_drain_rbuf;
		2116	$self->{tls} or return; # tls session might have gone away in callback
		2117	}
		2118
		2119	$tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
		2120	return $self->_tls_error ($tmp)
		2121	if $tmp != $ERROR_WANT_READ
		2122	&& ($tmp != $ERROR_SYSCALL || $!);
		2123
		2124	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
809	$self->{wbuf} .= $buf;	2125	$self->{wbuf} .= $tmp;
810	$self->_drain_wbuf;	2126	$self->_drain_wbuf;
		2127	$self->{tls} or return; # tls session might have gone away in callback
811	}	2128	}
812		2129
813	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {	2130	$self->{_on_starttls}
814	$self->{rbuf} .= $buf;	2131	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
815	$self->_drain_rbuf;	2132	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	}	2133	}
831		2134
832	=item $handle->starttls ($tls[, $tls_ctx])	2135	=item $handle->starttls ($tls[, $tls_ctx])
833		2136
834	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	2137	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	2138	object is created, you can also do that at a later time by calling
836	C<starttls>.	2139	C<starttls>. See the C<tls> constructor argument for general info.
		2140
		2141	Starting TLS is currently an asynchronous operation - when you push some
		2142	write data and then call C<< ->starttls >> then TLS negotiation will start
		2143	immediately, after which the queued write data is then sent. This might
		2144	change in future versions, so best make sure you have no outstanding write
		2145	data when calling this method.
837		2146
838	The first argument is the same as the C<tls> constructor argument (either	2147	The first argument is the same as the C<tls> constructor argument (either
839	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	2148	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
840		2149
841	The second argument is the optional C<Net::SSLeay::CTX> object that is	2150	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.	2151	when AnyEvent::Handle has to create its own TLS connection object, or
		2152	a hash reference with C<< key => value >> pairs that will be used to
		2153	construct a new context.
843		2154
844	=cut	2155	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
		2156	context in C<< $handle->{tls_ctx} >> after this call and can be used or
		2157	changed to your liking. Note that the handshake might have already started
		2158	when this function returns.
845		2159
846	# TODO: maybe document...	2160	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		2161	handshakes on the same stream. It is best to not attempt to use the
		2162	stream after stopping TLS.
		2163
		2164	This method may invoke callbacks (and therefore the handle might be
		2165	destroyed after it returns).
		2166
		2167	=cut
		2168
		2169	our %TLS_CACHE; #TODO not yet documented, should we?
		2170
847	sub starttls {	2171	sub starttls {
848	my ($self, $ssl, $ctx) = @_;	2172	my ($self, $tls, $ctx) = @_;
849		2173
850	$self->stoptls;	2174	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		2175	if $self->{tls};
851		2176
852	if ($ssl eq "accept") {	2177	unless (defined $AnyEvent::TLS::VERSION) {
853	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2178	eval {
854	Net::SSLeay::set_accept_state ($ssl);	2179	require Net::SSLeay;
855	} elsif ($ssl eq "connect") {	2180	require AnyEvent::TLS;
856	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2181	1
857	Net::SSLeay::set_connect_state ($ssl);	2182	} or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
		2183	}
		2184
		2185	$self->{tls} = $tls;
		2186	$self->{tls_ctx} = $ctx if @_ > 2;
		2187
		2188	return unless $self->{fh};
		2189
		2190	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		2191	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		2192
		2193	$tls = delete $self->{tls};
		2194	$ctx = $self->{tls_ctx};
		2195
		2196	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		2197
		2198	if ("HASH" eq ref $ctx) {
		2199	if ($ctx->{cache}) {
		2200	my $key = $ctx+0;
		2201	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		2202	} else {
		2203	$ctx = new AnyEvent::TLS %$ctx;
		2204	}
		2205	}
858	}	2206
859		2207	$self->{tls_ctx} = $ctx || TLS_CTX ();
860	$self->{tls} = $ssl;	2208	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
861		2209
862	# basically, this is deep magic (because SSL_read should have the same issues)	2210	# basically, this is deep magic (because SSL_read should have the same issues)
863	# but the openssl maintainers basically said: "trust us, it just works".	2211	# but the openssl maintainers basically said: "trust us, it just works".
864	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	2212	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
865	# and mismaintained ssleay-module doesn't even offer them).	2213	# and mismaintained ssleay-module doesn't even offer them).
866	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	2214	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		2215	#
		2216	# in short: this is a mess.
		2217	#
		2218	# note that we do not try to keep the length constant between writes as we are required to do.
		2219	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		2220	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		2221	# have identity issues in that area.
867	Net::SSLeay::CTX_set_mode ($self->{tls},	2222	# Net::SSLeay::CTX_set_mode ($ssl,
868	(eval { Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2223	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
869	| (eval { Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2224	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		2225	Net::SSLeay::CTX_set_mode ($tls, 1|2);
870		2226
871	$self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2227	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
872	$self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2228	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
873		2229
		2230	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2231	$self->{rbuf} = "";
		2232
874	Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio});	2233	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
875		2234
876	$self->{filter_w} = sub {	2235	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
877	$_[0]{tls_wbuf} .= ${$_[1]};	2236	if $self->{on_starttls};
878	&_dotls;	2237
879	};	2238	&_dotls; # need to trigger the initial handshake
880	$self->{filter_r} = sub {	2239	$self->start_read; # make sure we actually do read
881	Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
882	&_dotls;
883	};
884	}	2240	}
885		2241
886	=item $handle->stoptls	2242	=item $handle->stoptls
887		2243
888	Destroys the SSL connection, if any. Partial read or write data will be	2244	Shuts down the SSL connection - this makes a proper EOF handshake by
889	lost.	2245	sending a close notify to the other side, but since OpenSSL doesn't
		2246	support non-blocking shut downs, it is not guaranteed that you can re-use
		2247	the stream afterwards.
		2248
		2249	This method may invoke callbacks (and therefore the handle might be
		2250	destroyed after it returns).
890		2251
891	=cut	2252	=cut
892		2253
893	sub stoptls {	2254	sub stoptls {
894	my ($self) = @_;	2255	my ($self) = @_;
895		2256
896	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	2257	if ($self->{tls} && $self->{fh}) {
897	delete $self->{tls_rbio};	2258	Net::SSLeay::shutdown ($self->{tls});
898	delete $self->{tls_wbio};	2259
899	delete $self->{tls_wbuf};	2260	&_dotls;
900	delete $self->{filter_r};	2261
901	delete $self->{filter_w};	2262	# # we don't give a shit. no, we do, but we can't. no...#d#
		2263	# # we, we... have to use openssl :/#d#
		2264	# &_freetls;#d#
		2265	}
902	}	2266	}
		2267
		2268	sub _freetls {
		2269	my ($self) = @_;
		2270
		2271	return unless $self->{tls};
		2272
		2273	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2274	if $self->{tls} > 0;
		2275
		2276	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		2277	}
		2278
		2279	=item $handle->resettls
		2280
		2281	This rarely-used method simply resets and TLS state on the handle, usually
		2282	causing data loss.
		2283
		2284	One case where it may be useful is when you want to skip over the data in
		2285	the stream but you are not interested in interpreting it, so data loss is
		2286	no concern.
		2287
		2288	=cut
		2289
		2290	*resettls = \&_freetls;
903		2291
904	sub DESTROY {	2292	sub DESTROY {
905	my $self = shift;	2293	my ($self) = @_;
906		2294
907	$self->stoptls;	2295	&_freetls;
		2296
		2297	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		2298
		2299	if ($linger && length $self->{wbuf} && $self->{fh}) {
		2300	my $fh = delete $self->{fh};
		2301	my $wbuf = delete $self->{wbuf};
		2302
		2303	my @linger;
		2304
		2305	push @linger, AE::io $fh, 1, sub {
		2306	my $len = syswrite $fh, $wbuf, length $wbuf;
		2307
		2308	if ($len > 0) {
		2309	substr $wbuf, 0, $len, "";
		2310	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != EWOULDBLOCK && $! != WSAEWOULDBLOCK)) {
		2311	@linger = (); # end
		2312	}
		2313	};
		2314	push @linger, AE::timer $linger, 0, sub {
		2315	@linger = ();
		2316	};
		2317	}
908	}	2318	}
		2319
		2320	=item $handle->destroy
		2321
		2322	Shuts down the handle object as much as possible - this call ensures that
		2323	no further callbacks will be invoked and as many resources as possible
		2324	will be freed. Any method you will call on the handle object after
		2325	destroying it in this way will be silently ignored (and it will return the
		2326	empty list).
		2327
		2328	Normally, you can just "forget" any references to an AnyEvent::Handle
		2329	object and it will simply shut down. This works in fatal error and EOF
		2330	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2331	callback, so when you want to destroy the AnyEvent::Handle object from
		2332	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2333	that case.
		2334
		2335	Destroying the handle object in this way has the advantage that callbacks
		2336	will be removed as well, so if those are the only reference holders (as
		2337	is common), then one doesn't need to do anything special to break any
		2338	reference cycles.
		2339
		2340	The handle might still linger in the background and write out remaining
		2341	data, as specified by the C<linger> option, however.
		2342
		2343	=cut
		2344
		2345	sub destroy {
		2346	my ($self) = @_;
		2347
		2348	$self->DESTROY;
		2349	%$self = ();
		2350	bless $self, "AnyEvent::Handle::destroyed";
		2351	}
		2352
		2353	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2354	#nop
		2355	}
		2356
		2357	=item $handle->destroyed
		2358
		2359	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2360	->destroy >>, true otherwise.
		2361
		2362	Can be useful to decide whether the handle is still valid after some
		2363	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2364	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2365	can destroy the handle, so work can be avoided by checking sometimes:
		2366
		2367	$hdl->starttls ("accept");
		2368	return if $hdl->destroyed;
		2369	$hdl->push_write (...
		2370
		2371	Note that the call to C<push_write> will silently be ignored if the handle
		2372	has been destroyed, so often you can just ignore the possibility of the
		2373	handle being destroyed.
		2374
		2375	=cut
		2376
		2377	sub destroyed { 0 }
		2378	sub AnyEvent::Handle::destroyed::destroyed { 1 }
909		2379
910	=item AnyEvent::Handle::TLS_CTX	2380	=item AnyEvent::Handle::TLS_CTX
911		2381
912	This function creates and returns the Net::SSLeay::CTX object used by	2382	This function creates and returns the AnyEvent::TLS object used by default
913	default for TLS mode.	2383	for TLS mode.
914		2384
915	The context is created like this:	2385	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		2386
925	=cut	2387	=cut
926		2388
927	our $TLS_CTX;	2389	our $TLS_CTX;
928		2390
929	sub TLS_CTX() {	2391	sub TLS_CTX() {
930	$TLS_CTX || do {	2392	$TLS_CTX ||= do {
931	require Net::SSLeay;	2393	require AnyEvent::TLS;
932		2394
933	Net::SSLeay::load_error_strings ();	2395	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	}	2396	}
943	}	2397	}
944		2398
945	=back	2399	=back
946		2400
		2401
		2402	=head1 NONFREQUENTLY ASKED QUESTIONS
		2403
		2404	=over 4
		2405
		2406	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2407	still get further invocations!
		2408
		2409	That's because AnyEvent::Handle keeps a reference to itself when handling
		2410	read or write callbacks.
		2411
		2412	It is only safe to "forget" the reference inside EOF or error callbacks,
		2413	from within all other callbacks, you need to explicitly call the C<<
		2414	->destroy >> method.
		2415
		2416	=item Why is my C<on_eof> callback never called?
		2417
		2418	Probably because your C<on_error> callback is being called instead: When
		2419	you have outstanding requests in your read queue, then an EOF is
		2420	considered an error as you clearly expected some data.
		2421
		2422	To avoid this, make sure you have an empty read queue whenever your handle
		2423	is supposed to be "idle" (i.e. connection closes are O.K.). You can set
		2424	an C<on_read> handler that simply pushes the first read requests in the
		2425	queue.
		2426
		2427	See also the next question, which explains this in a bit more detail.
		2428
		2429	=item How can I serve requests in a loop?
		2430
		2431	Most protocols consist of some setup phase (authentication for example)
		2432	followed by a request handling phase, where the server waits for requests
		2433	and handles them, in a loop.
		2434
		2435	There are two important variants: The first (traditional, better) variant
		2436	handles requests until the server gets some QUIT command, causing it to
		2437	close the connection first (highly desirable for a busy TCP server). A
		2438	client dropping the connection is an error, which means this variant can
		2439	detect an unexpected detection close.
		2440
		2441	To handle this case, always make sure you have a non-empty read queue, by
		2442	pushing the "read request start" handler on it:
		2443
		2444	# we assume a request starts with a single line
		2445	my @start_request; @start_request = (line => sub {
		2446	my ($hdl, $line) = @_;
		2447
		2448	... handle request
		2449
		2450	# push next request read, possibly from a nested callback
		2451	$hdl->push_read (@start_request);
		2452	});
		2453
		2454	# auth done, now go into request handling loop
		2455	# now push the first @start_request
		2456	$hdl->push_read (@start_request);
		2457
		2458	By always having an outstanding C<push_read>, the handle always expects
		2459	some data and raises the C<EPIPE> error when the connction is dropped
		2460	unexpectedly.
		2461
		2462	The second variant is a protocol where the client can drop the connection
		2463	at any time. For TCP, this means that the server machine may run out of
		2464	sockets easier, and in general, it means you cannot distinguish a protocl
		2465	failure/client crash from a normal connection close. Nevertheless, these
		2466	kinds of protocols are common (and sometimes even the best solution to the
		2467	problem).
		2468
		2469	Having an outstanding read request at all times is possible if you ignore
		2470	C<EPIPE> errors, but this doesn't help with when the client drops the
		2471	connection during a request, which would still be an error.
		2472
		2473	A better solution is to push the initial request read in an C<on_read>
		2474	callback. This avoids an error, as when the server doesn't expect data
		2475	(i.e. is idly waiting for the next request, an EOF will not raise an
		2476	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2477	and simpler:
		2478
		2479	# auth done, now go into request handling loop
		2480	$hdl->on_read (sub {
		2481	my ($hdl) = @_;
		2482
		2483	# called each time we receive data but the read queue is empty
		2484	# simply start read the request
		2485
		2486	$hdl->push_read (line => sub {
		2487	my ($hdl, $line) = @_;
		2488
		2489	... handle request
		2490
		2491	# do nothing special when the request has been handled, just
		2492	# let the request queue go empty.
		2493	});
		2494	});
		2495
		2496	=item I get different callback invocations in TLS mode/Why can't I pause
		2497	reading?
		2498
		2499	Unlike, say, TCP, TLS connections do not consist of two independent
		2500	communication channels, one for each direction. Or put differently, the
		2501	read and write directions are not independent of each other: you cannot
		2502	write data unless you are also prepared to read, and vice versa.
		2503
		2504	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2505	callback invocations when you are not expecting any read data - the reason
		2506	is that AnyEvent::Handle always reads in TLS mode.
		2507
		2508	During the connection, you have to make sure that you always have a
		2509	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2510	connection (or when you no longer want to use it) you can call the
		2511	C<destroy> method.
		2512
		2513	=item How do I read data until the other side closes the connection?
		2514
		2515	If you just want to read your data into a perl scalar, the easiest way
		2516	to achieve this is by setting an C<on_read> callback that does nothing,
		2517	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2518	will be in C<$_[0]{rbuf}>:
		2519
		2520	$handle->on_read (sub { });
		2521	$handle->on_eof (undef);
		2522	$handle->on_error (sub {
		2523	my $data = delete $_[0]{rbuf};
		2524	});
		2525
		2526	Note that this example removes the C<rbuf> member from the handle object,
		2527	which is not normally allowed by the API. It is expressly permitted in
		2528	this case only, as the handle object needs to be destroyed afterwards.
		2529
		2530	The reason to use C<on_error> is that TCP connections, due to latencies
		2531	and packets loss, might get closed quite violently with an error, when in
		2532	fact all data has been received.
		2533
		2534	It is usually better to use acknowledgements when transferring data,
		2535	to make sure the other side hasn't just died and you got the data
		2536	intact. This is also one reason why so many internet protocols have an
		2537	explicit QUIT command.
		2538
		2539	=item I don't want to destroy the handle too early - how do I wait until
		2540	all data has been written?
		2541
		2542	After writing your last bits of data, set the C<on_drain> callback
		2543	and destroy the handle in there - with the default setting of
		2544	C<low_water_mark> this will be called precisely when all data has been
		2545	written to the socket:
		2546
		2547	$handle->push_write (...);
		2548	$handle->on_drain (sub {
		2549	AE::log debug => "All data submitted to the kernel.";
		2550	undef $handle;
		2551	});
		2552
		2553	If you just want to queue some data and then signal EOF to the other side,
		2554	consider using C<< ->push_shutdown >> instead.
		2555
		2556	=item I want to contact a TLS/SSL server, I don't care about security.
		2557
		2558	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2559	connect to it and then create the AnyEvent::Handle with the C<tls>
		2560	parameter:
		2561
		2562	tcp_connect $host, $port, sub {
		2563	my ($fh) = @_;
		2564
		2565	my $handle = new AnyEvent::Handle
		2566	fh => $fh,
		2567	tls => "connect",
		2568	on_error => sub { ... };
		2569
		2570	$handle->push_write (...);
		2571	};
		2572
		2573	=item I want to contact a TLS/SSL server, I do care about security.
		2574
		2575	Then you should additionally enable certificate verification, including
		2576	peername verification, if the protocol you use supports it (see
		2577	L<AnyEvent::TLS>, C<verify_peername>).
		2578
		2579	E.g. for HTTPS:
		2580
		2581	tcp_connect $host, $port, sub {
		2582	my ($fh) = @_;
		2583
		2584	my $handle = new AnyEvent::Handle
		2585	fh => $fh,
		2586	peername => $host,
		2587	tls => "connect",
		2588	tls_ctx => { verify => 1, verify_peername => "https" },
		2589	...
		2590
		2591	Note that you must specify the hostname you connected to (or whatever
		2592	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2593	peername verification will be done.
		2594
		2595	The above will use the system-dependent default set of trusted CA
		2596	certificates. If you want to check against a specific CA, add the
		2597	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2598
		2599	tls_ctx => {
		2600	verify => 1,
		2601	verify_peername => "https",
		2602	ca_file => "my-ca-cert.pem",
		2603	},
		2604
		2605	=item I want to create a TLS/SSL server, how do I do that?
		2606
		2607	Well, you first need to get a server certificate and key. You have
		2608	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2609	self-signed certificate (cheap. check the search engine of your choice,
		2610	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2611	nice program for that purpose).
		2612
		2613	Then create a file with your private key (in PEM format, see
		2614	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2615	file should then look like this:
		2616
		2617	-----BEGIN RSA PRIVATE KEY-----
		2618	...header data
		2619	... lots of base64'y-stuff
		2620	-----END RSA PRIVATE KEY-----
		2621
		2622	-----BEGIN CERTIFICATE-----
		2623	... lots of base64'y-stuff
		2624	-----END CERTIFICATE-----
		2625
		2626	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2627	specify this file as C<cert_file>:
		2628
		2629	tcp_server undef, $port, sub {
		2630	my ($fh) = @_;
		2631
		2632	my $handle = new AnyEvent::Handle
		2633	fh => $fh,
		2634	tls => "accept",
		2635	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2636	...
		2637
		2638	When you have intermediate CA certificates that your clients might not
		2639	know about, just append them to the C<cert_file>.
		2640
		2641	=back
		2642
		2643	=head1 SUBCLASSING AnyEvent::Handle
		2644
		2645	In many cases, you might want to subclass AnyEvent::Handle.
		2646
		2647	To make this easier, a given version of AnyEvent::Handle uses these
		2648	conventions:
		2649
		2650	=over 4
		2651
		2652	=item * all constructor arguments become object members.
		2653
		2654	At least initially, when you pass a C<tls>-argument to the constructor it
		2655	will end up in C<< $handle->{tls} >>. Those members might be changed or
		2656	mutated later on (for example C<tls> will hold the TLS connection object).
		2657
		2658	=item * other object member names are prefixed with an C<_>.
		2659
		2660	All object members not explicitly documented (internal use) are prefixed
		2661	with an underscore character, so the remaining non-C<_>-namespace is free
		2662	for use for subclasses.
		2663
		2664	=item * all members not documented here and not prefixed with an underscore
		2665	are free to use in subclasses.
		2666
		2667	Of course, new versions of AnyEvent::Handle may introduce more "public"
		2668	member variables, but that's just life. At least it is documented.
		2669
		2670	=back
		2671
947	=head1 AUTHOR	2672	=head1 AUTHOR
948		2673
949	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	2674	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
950		2675
951	=cut	2676	=cut
952		2677
953	1; # End of AnyEvent::Handle	2678	1
		2679

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