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Revision 1.239 by root, Tue Dec 10 20:39:12 2013 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict;
5
6	use AnyEvent ();
7	use AnyEvent::Util qw(WSAWOULDBLOCK);
8	use Scalar::Util ();
9	use Carp ();
10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;
12
13	=head1 NAME	1	=head1 NAME
14		2
15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17	=cut
18
19	our $VERSION = '0.04';
20		4
21	=head1 SYNOPSIS	5	=head1 SYNOPSIS
22		6
23	use AnyEvent;	7	use AnyEvent;
24	use AnyEvent::Handle;	8	use AnyEvent::Handle;
25		9
26	my $cv = AnyEvent->condvar;	10	my $cv = AnyEvent->condvar;
27		11
28	my $handle =	12	my $hdl; $hdl = new AnyEvent::Handle
29	AnyEvent::Handle->new (
30	fh => \*STDIN,	13	fh => \*STDIN,
31	on_eof => sub {	14	on_error => sub {
32	$cv->broadcast;	15	my ($hdl, $fatal, $msg) = @_;
33	},	16	AE::log error => $msg;
		17	$hdl->destroy;
		18	$cv->send;
34	);	19	};
35		20
36	# send some request line	21	# send some request line
37	$handle->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
38		23
39	# read the response line	24	# read the response line
40	$handle->push_read (line => sub {	25	$hdl->push_read (line => sub {
41	my ($handle, $line) = @_;	26	my ($hdl, $line) = @_;
42	warn "read line <$line>\n";	27	say "got line <$line>";
43	$cv->send;	28	$cv->send;
44	});	29	});
45		30
46	$cv->recv;	31	$cv->recv;
47		32
48	=head1 DESCRIPTION	33	=head1 DESCRIPTION
49		34
50	This module is a helper module to make it easier to do event-based I/O on	35	This is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	36	stream-based filehandles (sockets, pipes, and other stream things).
52	on sockets see L<AnyEvent::Util>.
53		37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
		40
54	In the following, when the documentation refers to of "bytes" then this	41	In the following, where the documentation refers to "bytes", it means
55	means characters. As sysread and syswrite are used for all I/O, their	42	characters. As sysread and syswrite are used for all I/O, their
56	treatment of characters applies to this module as well.	43	treatment of characters applies to this module as well.
		44
		45	At the very minimum, you should specify C<fh> or C<connect>, and the
		46	C<on_error> callback.
57		47
58	All callbacks will be invoked with the handle object as their first	48	All callbacks will be invoked with the handle object as their first
59	argument.	49	argument.
60		50
		51	=cut
		52
		53	package AnyEvent::Handle;
		54
		55	use Scalar::Util ();
		56	use List::Util ();
		57	use Carp ();
		58	use Errno qw(EAGAIN EINTR);
		59
		60	use AnyEvent (); BEGIN { AnyEvent::common_sense }
		61	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		62
		63	our $VERSION = $AnyEvent::VERSION;
		64
		65	sub _load_func($) {
		66	my $func = $_[0];
		67
		68	unless (defined &$func) {
		69	my $pkg = $func;
		70	do {
		71	$pkg =~ s/::[^:]+$//
		72	or return;
		73	eval "require $pkg";
		74	} until defined &$func;
		75	}
		76
		77	\&$func
		78	}
		79
		80	sub MAX_READ_SIZE() { 131072 }
		81
61	=head1 METHODS	82	=head1 METHODS
62		83
63	=over 4	84	=over 4
64		85
65	=item B<new (%args)>	86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
66		87
67	The constructor supports these arguments (all as key => value pairs).	88	The constructor supports these arguments (all as C<< key => value >> pairs).
68		89
69	=over 4	90	=over 4
70		91
71	=item fh => $filehandle [MANDATORY]	92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
72		93
73	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
74
75	NOTE: The filehandle will be set to non-blocking (using	95	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		97	that mode.
77		98
78	=item on_eof => $cb->($self)	99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
79		100
80	Set the callback to be called on EOF.	101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
81		104
82	While not mandatory, it is highly recommended to set an eof callback,	105	You have to specify either this parameter, or C<fh>, above.
83	otherwise you might end up with a closed socket while you are still
84	waiting for data.
85		106
		107	It is possible to push requests on the read and write queues, and modify
		108	properties of the stream, even while AnyEvent::Handle is connecting.
		109
		110	When this parameter is specified, then the C<on_prepare>,
		111	C<on_connect_error> and C<on_connect> callbacks will be called under the
		112	appropriate circumstances:
		113
		114	=over 4
		115
86	=item on_error => $cb->($self)	116	=item on_prepare => $cb->($handle)
87		117
		118	This (rarely used) callback is called before a new connection is
		119	attempted, but after the file handle has been created (you can access that
		120	file handle via C<< $handle->{fh} >>). It could be used to prepare the
		121	file handle with parameters required for the actual connect (as opposed to
		122	settings that can be changed when the connection is already established).
		123
		124	The return value of this callback should be the connect timeout value in
		125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
		126	default timeout is to be used).
		127
		128	=item on_connect => $cb->($handle, $host, $port, $retry->())
		129
		130	This callback is called when a connection has been successfully established.
		131
		132	The peer's numeric host and port (the socket peername) are passed as
		133	parameters, together with a retry callback. At the time it is called the
		134	read and write queues, EOF status, TLS status and similar properties of
		135	the handle will have been reset.
		136
		137	It is not allowed to use the read or write queues while the handle object
		138	is connecting.
		139
		140	If, for some reason, the handle is not acceptable, calling C<$retry> will
		141	continue with the next connection target (in case of multi-homed hosts or
		142	SRV records there can be multiple connection endpoints). The C<$retry>
		143	callback can be invoked after the connect callback returns, i.e. one can
		144	start a handshake and then decide to retry with the next host if the
		145	handshake fails.
		146
		147	In most cases, you should ignore the C<$retry> parameter.
		148
		149	=item on_connect_error => $cb->($handle, $message)
		150
		151	This callback is called when the connection could not be
		152	established. C<$!> will contain the relevant error code, and C<$message> a
		153	message describing it (usually the same as C<"$!">).
		154
		155	If this callback isn't specified, then C<on_error> will be called with a
		156	fatal error instead.
		157
		158	=back
		159
		160	=item on_error => $cb->($handle, $fatal, $message)
		161
88	This is the fatal error callback, that is called when, well, a fatal error	162	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	163	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	164	connect, or a read error.
91		165
92	The object will not be in a usable state when this callback has been	166	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	167	fatal errors the handle object will be destroyed (by a call to C<< ->
		168	destroy >>) after invoking the error callback (which means you are free to
		169	examine the handle object). Examples of fatal errors are an EOF condition
		170	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		171	cases where the other side can close the connection at will, it is
		172	often easiest to not report C<EPIPE> errors in this callback.
94		173
		174	AnyEvent::Handle tries to find an appropriate error code for you to check
		175	against, but in some cases (TLS errors), this does not work well.
		176
		177	If you report the error to the user, it is recommended to always output
		178	the C<$message> argument in human-readable error messages (you don't need
		179	to report C<"$!"> if you report C<$message>).
		180
		181	If you want to react programmatically to the error, then looking at C<$!>
		182	and comparing it against some of the documented C<Errno> values is usually
		183	better than looking at the C<$message>.
		184
		185	Non-fatal errors can be retried by returning, but it is recommended
		186	to simply ignore this parameter and instead abondon the handle object
		187	when this callback is invoked. Examples of non-fatal errors are timeouts
		188	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		189
95	On callback entrance, the value of C<$!> contains the operating system	190	On entry to the callback, the value of C<$!> contains the operating
96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).	191	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
97		192	C<EPROTO>).
98	The callback should throw an exception. If it returns, then
99	AnyEvent::Handle will C<croak> for you.
100		193
101	While not mandatory, it is I<highly> recommended to set this callback, as	194	While not mandatory, it is I<highly> recommended to set this callback, as
102	you will not be notified of errors otherwise. The default simply calls	195	you will not be notified of errors otherwise. The default just calls
103	die.	196	C<croak>.
104		197
105	=item on_read => $cb->($self)	198	=item on_read => $cb->($handle)
106		199
107	This sets the default read callback, which is called when data arrives	200	This sets the default read callback, which is called when data arrives
108	and no read request is in the queue.	201	and no read request is in the queue (unlike read queue callbacks, this
		202	callback will only be called when at least one octet of data is in the
		203	read buffer).
109		204
110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	205	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111	method or access the C<$self->{rbuf}> member directly.	206	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		207	must not enlarge or modify the read buffer, you can only remove data at
		208	the beginning from it.
112		209
		210	You can also call C<< ->push_read (...) >> or any other function that
		211	modifies the read queue. Or do both. Or ...
		212
113	When an EOF condition is detected then AnyEvent::Handle will first try to	213	When an EOF condition is detected, AnyEvent::Handle will first try to
114	feed all the remaining data to the queued callbacks and C<on_read> before	214	feed all the remaining data to the queued callbacks and C<on_read> before
115	calling the C<on_eof> callback. If no progress can be made, then a fatal	215	calling the C<on_eof> callback. If no progress can be made, then a fatal
116	error will be raised (with C<$!> set to C<EPIPE>).	216	error will be raised (with C<$!> set to C<EPIPE>).
117		217
		218	Note that, unlike requests in the read queue, an C<on_read> callback
		219	doesn't mean you I<require> some data: if there is an EOF and there
		220	are outstanding read requests then an error will be flagged. With an
		221	C<on_read> callback, the C<on_eof> callback will be invoked.
		222
		223	=item on_eof => $cb->($handle)
		224
		225	Set the callback to be called when an end-of-file condition is detected,
		226	i.e. in the case of a socket, when the other side has closed the
		227	connection cleanly, and there are no outstanding read requests in the
		228	queue (if there are read requests, then an EOF counts as an unexpected
		229	connection close and will be flagged as an error).
		230
		231	For sockets, this just means that the other side has stopped sending data,
		232	you can still try to write data, and, in fact, one can return from the EOF
		233	callback and continue writing data, as only the read part has been shut
		234	down.
		235
		236	If an EOF condition has been detected but no C<on_eof> callback has been
		237	set, then a fatal error will be raised with C<$!> set to <0>.
		238
118	=item on_drain => $cb->()	239	=item on_drain => $cb->($handle)
119		240
120	This sets the callback that is called when the write buffer becomes empty	241	This sets the callback that is called once when the write buffer becomes
121	(or when the callback is set and the buffer is empty already).	242	empty (and immediately when the handle object is created).
122		243
123	To append to the write buffer, use the C<< ->push_write >> method.	244	To append to the write buffer, use the C<< ->push_write >> method.
		245
		246	This callback is useful when you don't want to put all of your write data
		247	into the queue at once, for example, when you want to write the contents
		248	of some file to the socket you might not want to read the whole file into
		249	memory and push it into the queue, but instead only read more data from
		250	the file when the write queue becomes empty.
		251
		252	=item timeout => $fractional_seconds
		253
		254	=item rtimeout => $fractional_seconds
		255
		256	=item wtimeout => $fractional_seconds
		257
		258	If non-zero, then these enables an "inactivity" timeout: whenever this
		259	many seconds pass without a successful read or write on the underlying
		260	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
		261	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		262	error will be raised).
		263
		264	There are three variants of the timeouts that work independently of each
		265	other, for both read and write (triggered when nothing was read I<OR>
		266	written), just read (triggered when nothing was read), and just write:
		267	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		268	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		269	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		270
		271	Note that timeout processing is active even when you do not have any
		272	outstanding read or write requests: If you plan to keep the connection
		273	idle then you should disable the timeout temporarily or ignore the
		274	timeout in the corresponding C<on_timeout> callback, in which case
		275	AnyEvent::Handle will simply restart the timeout.
		276
		277	Zero (the default) disables the corresponding timeout.
		278
		279	=item on_timeout => $cb->($handle)
		280
		281	=item on_rtimeout => $cb->($handle)
		282
		283	=item on_wtimeout => $cb->($handle)
		284
		285	Called whenever the inactivity timeout passes. If you return from this
		286	callback, then the timeout will be reset as if some activity had happened,
		287	so this condition is not fatal in any way.
124		288
125	=item rbuf_max => <bytes>	289	=item rbuf_max => <bytes>
126		290
127	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	291	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128	when the read buffer ever (strictly) exceeds this size. This is useful to	292	when the read buffer ever (strictly) exceeds this size. This is useful to
129	avoid denial-of-service attacks.	293	avoid some forms of denial-of-service attacks.
130		294
131	For example, a server accepting connections from untrusted sources should	295	For example, a server accepting connections from untrusted sources should
132	be configured to accept only so-and-so much data that it cannot act on	296	be configured to accept only so-and-so much data that it cannot act on
133	(for example, when expecting a line, an attacker could send an unlimited	297	(for example, when expecting a line, an attacker could send an unlimited
134	amount of data without a callback ever being called as long as the line	298	amount of data without a callback ever being called as long as the line
135	isn't finished).	299	isn't finished).
136		300
		301	=item wbuf_max => <bytes>
		302
		303	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		304	when the write buffer ever (strictly) exceeds this size. This is useful to
		305	avoid some forms of denial-of-service attacks.
		306
		307	Although the units of this parameter is bytes, this is the I<raw> number
		308	of bytes not yet accepted by the kernel. This can make a difference when
		309	you e.g. use TLS, as TLS typically makes your write data larger (but it
		310	can also make it smaller due to compression).
		311
		312	As an example of when this limit is useful, take a chat server that sends
		313	chat messages to a client. If the client does not read those in a timely
		314	manner then the send buffer in the server would grow unbounded.
		315
		316	=item autocork => <boolean>
		317
		318	When disabled (the default), C<push_write> will try to immediately
		319	write the data to the handle if possible. This avoids having to register
		320	a write watcher and wait for the next event loop iteration, but can
		321	be inefficient if you write multiple small chunks (on the wire, this
		322	disadvantage is usually avoided by your kernel's nagle algorithm, see
		323	C<no_delay>, but this option can save costly syscalls).
		324
		325	When enabled, writes will always be queued till the next event loop
		326	iteration. This is efficient when you do many small writes per iteration,
		327	but less efficient when you do a single write only per iteration (or when
		328	the write buffer often is full). It also increases write latency.
		329
		330	=item no_delay => <boolean>
		331
		332	When doing small writes on sockets, your operating system kernel might
		333	wait a bit for more data before actually sending it out. This is called
		334	the Nagle algorithm, and usually it is beneficial.
		335
		336	In some situations you want as low a delay as possible, which can be
		337	accomplishd by setting this option to a true value.
		338
		339	The default is your operating system's default behaviour (most likely
		340	enabled). This option explicitly enables or disables it, if possible.
		341
		342	=item keepalive => <boolean>
		343
		344	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		345	normally, TCP connections have no time-out once established, so TCP
		346	connections, once established, can stay alive forever even when the other
		347	side has long gone. TCP keepalives are a cheap way to take down long-lived
		348	TCP connections when the other side becomes unreachable. While the default
		349	is OS-dependent, TCP keepalives usually kick in after around two hours,
		350	and, if the other side doesn't reply, take down the TCP connection some 10
		351	to 15 minutes later.
		352
		353	It is harmless to specify this option for file handles that do not support
		354	keepalives, and enabling it on connections that are potentially long-lived
		355	is usually a good idea.
		356
		357	=item oobinline => <boolean>
		358
		359	BSD majorly fucked up the implementation of TCP urgent data. The result
		360	is that almost no OS implements TCP according to the specs, and every OS
		361	implements it slightly differently.
		362
		363	If you want to handle TCP urgent data, then setting this flag (the default
		364	is enabled) gives you the most portable way of getting urgent data, by
		365	putting it into the stream.
		366
		367	Since BSD emulation of OOB data on top of TCP's urgent data can have
		368	security implications, AnyEvent::Handle sets this flag automatically
		369	unless explicitly specified. Note that setting this flag after
		370	establishing a connection I<may> be a bit too late (data loss could
		371	already have occured on BSD systems), but at least it will protect you
		372	from most attacks.
		373
137	=item read_size => <bytes>	374	=item read_size => <bytes>
138		375
139	The default read block size (the amount of bytes this module will try to read	376	The initial read block size, the number of bytes this module will try
140	on each [loop iteration). Default: C<4096>.	377	to read during each loop iteration. Each handle object will consume
		378	at least this amount of memory for the read buffer as well, so when
		379	handling many connections watch out for memory requirements). See also
		380	C<max_read_size>. Default: C<2048>.
		381
		382	=item max_read_size => <bytes>
		383
		384	The maximum read buffer size used by the dynamic adjustment
		385	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		386	one go it will double C<read_size> up to the maximum given by this
		387	option. Default: C<131072> or C<read_size>, whichever is higher.
141		388
142	=item low_water_mark => <bytes>	389	=item low_water_mark => <bytes>
143		390
144	Sets the amount of bytes (default: C<0>) that make up an "empty" write	391	Sets the number of bytes (default: C<0>) that make up an "empty" write
145	buffer: If the write reaches this size or gets even samller it is	392	buffer: If the buffer reaches this size or gets even samller it is
146	considered empty.	393	considered empty.
147		394
		395	Sometimes it can be beneficial (for performance reasons) to add data to
		396	the write buffer before it is fully drained, but this is a rare case, as
		397	the operating system kernel usually buffers data as well, so the default
		398	is good in almost all cases.
		399
		400	=item linger => <seconds>
		401
		402	If this is non-zero (default: C<3600>), the destructor of the
		403	AnyEvent::Handle object will check whether there is still outstanding
		404	write data and will install a watcher that will write this data to the
		405	socket. No errors will be reported (this mostly matches how the operating
		406	system treats outstanding data at socket close time).
		407
		408	This will not work for partial TLS data that could not be encoded
		409	yet. This data will be lost. Calling the C<stoptls> method in time might
		410	help.
		411
		412	=item peername => $string
		413
		414	A string used to identify the remote site - usually the DNS hostname
		415	(I<not> IDN!) used to create the connection, rarely the IP address.
		416
		417	Apart from being useful in error messages, this string is also used in TLS
		418	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		419	verification will be skipped when C<peername> is not specified or is
		420	C<undef>.
		421
148	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	422	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149		423
150	When this parameter is given, it enables TLS (SSL) mode, that means it	424	When this parameter is given, it enables TLS (SSL) mode, that means
151	will start making tls handshake and will transparently encrypt/decrypt	425	AnyEvent will start a TLS handshake as soon as the connection has been
152	data.	426	established and will transparently encrypt/decrypt data afterwards.
		427
		428	All TLS protocol errors will be signalled as C<EPROTO>, with an
		429	appropriate error message.
153		430
154	TLS mode requires Net::SSLeay to be installed (it will be loaded	431	TLS mode requires Net::SSLeay to be installed (it will be loaded
155	automatically when you try to create a TLS handle).	432	automatically when you try to create a TLS handle): this module doesn't
		433	have a dependency on that module, so if your module requires it, you have
		434	to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
		435	old, you get an C<EPROTO> error.
156		436
157	For the TLS server side, use C<accept>, and for the TLS client side of a	437	Unlike TCP, TLS has a server and client side: for the TLS server side, use
158	connection, use C<connect> mode.	438	C<accept>, and for the TLS client side of a connection, use C<connect>
		439	mode.
159		440
160	You can also provide your own TLS connection object, but you have	441	You can also provide your own TLS connection object, but you have
161	to make sure that you call either C<Net::SSLeay::set_connect_state>	442	to make sure that you call either C<Net::SSLeay::set_connect_state>
162	or C<Net::SSLeay::set_accept_state> on it before you pass it to	443	or C<Net::SSLeay::set_accept_state> on it before you pass it to
163	AnyEvent::Handle.	444	AnyEvent::Handle. Also, this module will take ownership of this connection
		445	object.
164		446
		447	At some future point, AnyEvent::Handle might switch to another TLS
		448	implementation, then the option to use your own session object will go
		449	away.
		450
		451	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		452	passing in the wrong integer will lead to certain crash. This most often
		453	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		454	segmentation fault.
		455
165	See the C<starttls> method if you need to start TLs negotiation later.	456	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
166		457
167	=item tls_ctx => $ssl_ctx	458	=item tls_ctx => $anyevent_tls
168		459
169	Use the given Net::SSLeay::CTX object to create the new TLS connection	460	Use the given C<AnyEvent::TLS> object to create the new TLS connection
170	(unless a connection object was specified directly). If this parameter is	461	(unless a connection object was specified directly). If this
171	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	462	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		463	C<AnyEvent::Handle::TLS_CTX>.
172		464
173	=item filter_r => $cb	465	Instead of an object, you can also specify a hash reference with C<< key
		466	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		467	new TLS context object.
174		468
175	=item filter_w => $cb	469	=item on_starttls => $cb->($handle, $success[, $error_message])
176		470
177	These exist, but are undocumented at this time.	471	This callback will be invoked when the TLS/SSL handshake has finished. If
		472	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		473	(C<on_stoptls> will not be called in this case).
		474
		475	The session in C<< $handle->{tls} >> can still be examined in this
		476	callback, even when the handshake was not successful.
		477
		478	TLS handshake failures will not cause C<on_error> to be invoked when this
		479	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		480
		481	Without this callback, handshake failures lead to C<on_error> being
		482	called as usual.
		483
		484	Note that you cannot just call C<starttls> again in this callback. If you
		485	need to do that, start an zero-second timer instead whose callback can
		486	then call C<< ->starttls >> again.
		487
		488	=item on_stoptls => $cb->($handle)
		489
		490	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		491	set, then it will be invoked after freeing the TLS session. If it is not,
		492	then a TLS shutdown condition will be treated like a normal EOF condition
		493	on the handle.
		494
		495	The session in C<< $handle->{tls} >> can still be examined in this
		496	callback.
		497
		498	This callback will only be called on TLS shutdowns, not when the
		499	underlying handle signals EOF.
		500
		501	=item json => L<JSON> or L<JSON::XS> object
		502
		503	This is the json coder object used by the C<json> read and write types.
		504
		505	If you don't supply it, then AnyEvent::Handle will create and use a
		506	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		507	texts.
		508
		509	Note that you are responsible to depend on the L<JSON> module if you want
		510	to use this functionality, as AnyEvent does not have a dependency on it
		511	itself.
		512
		513	=item cbor => L<CBOR::XS> object
		514
		515	This is the cbor coder object used by the C<cbor> read and write types.
		516
		517	If you don't supply it, then AnyEvent::Handle will create and use a
		518	suitable one (on demand), which will write CBOR without using extensions,
		519	if possible. texts.
		520
		521	Note that you are responsible to depend on the L<CBOR::XS> module if you
		522	want to use this functionality, as AnyEvent does not have a dependency on
		523	it itself.
178		524
179	=back	525	=back
180		526
181	=cut	527	=cut
182		528
183	sub new {	529	sub new {
184	my $class = shift;	530	my $class = shift;
185
186	my $self = bless { @_ }, $class;	531	my $self = bless { @_ }, $class;
187		532
188	$self->{fh} or Carp::croak "mandatory argument fh is missing";	533	if ($self->{fh}) {
		534	$self->_start;
		535	return unless $self->{fh}; # could be gone by now
		536
		537	} elsif ($self->{connect}) {
		538	require AnyEvent::Socket;
		539
		540	$self->{peername} = $self->{connect}[0]
		541	unless exists $self->{peername};
		542
		543	$self->{_skip_drain_rbuf} = 1;
		544
		545	{
		546	Scalar::Util::weaken (my $self = $self);
		547
		548	$self->{_connect} =
		549	AnyEvent::Socket::tcp_connect (
		550	$self->{connect}[0],
		551	$self->{connect}[1],
		552	sub {
		553	my ($fh, $host, $port, $retry) = @_;
		554
		555	delete $self->{_connect}; # no longer needed
		556
		557	if ($fh) {
		558	$self->{fh} = $fh;
		559
		560	delete $self->{_skip_drain_rbuf};
		561	$self->_start;
		562
		563	$self->{on_connect}
		564	and $self->{on_connect}($self, $host, $port, sub {
		565	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		566	$self->{_skip_drain_rbuf} = 1;
		567	&$retry;
		568	});
		569
		570	} else {
		571	if ($self->{on_connect_error}) {
		572	$self->{on_connect_error}($self, "$!");
		573	$self->destroy if $self;
		574	} else {
		575	$self->_error ($!, 1);
		576	}
		577	}
		578	},
		579	sub {
		580	local $self->{fh} = $_[0];
		581
		582	$self->{on_prepare}
		583	? $self->{on_prepare}->($self)
		584	: ()
		585	}
		586	);
		587	}
		588
		589	} else {
		590	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		591	}
		592
		593	$self
		594	}
		595
		596	sub _start {
		597	my ($self) = @_;
		598
		599	# too many clueless people try to use udp and similar sockets
		600	# with AnyEvent::Handle, do them a favour.
		601	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		602	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		603	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
189		604
190	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	605	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
191		606
192	if ($self->{tls}) {	607	$self->{_activity} =
193	require Net::SSLeay;	608	$self->{_ractivity} =
		609	$self->{_wactivity} = AE::now;
		610
		611	$self->{read_size} ||= 2048;
		612	$self->{max_read_size} = $self->{read_size}
		613	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		614
		615	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		616	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		617	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		618
		619	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		620	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		621
		622	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		623
194	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	624	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
195	}	625	if $self->{tls};
196		626
197	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
198	$self->on_error (delete $self->{on_error}) if $self->{on_error};
199	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	627	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
200	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
201		628
202	$self->start_read;	629	$self->start_read
		630	if $self->{on_read} || @{ $self->{_queue} };
203		631
204	$self	632	$self->_drain_wbuf;
205	}	633	}
206		634
207	sub _shutdown {
208	my ($self) = @_;
209
210	delete $self->{_rw};
211	delete $self->{_ww};
212	delete $self->{fh};
213	}
214
215	sub error {	635	sub _error {
216	my ($self) = @_;	636	my ($self, $errno, $fatal, $message) = @_;
217		637
218	{	638	$! = $errno;
219	local $!;	639	$message ||= "$!";
220	$self->_shutdown;
221	}
222		640
223	$self->{on_error}($self)
224	if $self->{on_error};	641	if ($self->{on_error}) {
225		642	$self->{on_error}($self, $fatal, $message);
		643	$self->destroy if $fatal;
		644	} elsif ($self->{fh} || $self->{connect}) {
		645	$self->destroy;
226	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	646	Carp::croak "AnyEvent::Handle uncaught error: $message";
		647	}
227	}	648	}
228		649
229	=item $fh = $handle->fh	650	=item $fh = $handle->fh
230		651
231	This method returns the file handle of the L<AnyEvent::Handle> object.	652	This method returns the file handle used to create the L<AnyEvent::Handle> object.
232		653
233	=cut	654	=cut
234		655
235	sub fh { $_[0]{fh} }	656	sub fh { $_[0]{fh} }
236		657
…		…
252		673
253	sub on_eof {	674	sub on_eof {
254	$_[0]{on_eof} = $_[1];	675	$_[0]{on_eof} = $_[1];
255	}	676	}
256		677
		678	=item $handle->on_timeout ($cb)
		679
		680	=item $handle->on_rtimeout ($cb)
		681
		682	=item $handle->on_wtimeout ($cb)
		683
		684	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		685	callback, or disables the callback (but not the timeout) if C<$cb> =
		686	C<undef>. See the C<timeout> constructor argument and method.
		687
		688	=cut
		689
		690	# see below
		691
		692	=item $handle->autocork ($boolean)
		693
		694	Enables or disables the current autocork behaviour (see C<autocork>
		695	constructor argument). Changes will only take effect on the next write.
		696
		697	=cut
		698
		699	sub autocork {
		700	$_[0]{autocork} = $_[1];
		701	}
		702
		703	=item $handle->no_delay ($boolean)
		704
		705	Enables or disables the C<no_delay> setting (see constructor argument of
		706	the same name for details).
		707
		708	=cut
		709
		710	sub no_delay {
		711	$_[0]{no_delay} = $_[1];
		712
		713	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		714	if $_[0]{fh};
		715	}
		716
		717	=item $handle->keepalive ($boolean)
		718
		719	Enables or disables the C<keepalive> setting (see constructor argument of
		720	the same name for details).
		721
		722	=cut
		723
		724	sub keepalive {
		725	$_[0]{keepalive} = $_[1];
		726
		727	eval {
		728	local $SIG{__DIE__};
		729	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		730	if $_[0]{fh};
		731	};
		732	}
		733
		734	=item $handle->oobinline ($boolean)
		735
		736	Enables or disables the C<oobinline> setting (see constructor argument of
		737	the same name for details).
		738
		739	=cut
		740
		741	sub oobinline {
		742	$_[0]{oobinline} = $_[1];
		743
		744	eval {
		745	local $SIG{__DIE__};
		746	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		747	if $_[0]{fh};
		748	};
		749	}
		750
		751	=item $handle->keepalive ($boolean)
		752
		753	Enables or disables the C<keepalive> setting (see constructor argument of
		754	the same name for details).
		755
		756	=cut
		757
		758	sub keepalive {
		759	$_[0]{keepalive} = $_[1];
		760
		761	eval {
		762	local $SIG{__DIE__};
		763	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		764	if $_[0]{fh};
		765	};
		766	}
		767
		768	=item $handle->on_starttls ($cb)
		769
		770	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		771
		772	=cut
		773
		774	sub on_starttls {
		775	$_[0]{on_starttls} = $_[1];
		776	}
		777
		778	=item $handle->on_stoptls ($cb)
		779
		780	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		781
		782	=cut
		783
		784	sub on_stoptls {
		785	$_[0]{on_stoptls} = $_[1];
		786	}
		787
		788	=item $handle->rbuf_max ($max_octets)
		789
		790	Configures the C<rbuf_max> setting (C<undef> disables it).
		791
		792	=item $handle->wbuf_max ($max_octets)
		793
		794	Configures the C<wbuf_max> setting (C<undef> disables it).
		795
		796	=cut
		797
		798	sub rbuf_max {
		799	$_[0]{rbuf_max} = $_[1];
		800	}
		801
		802	sub wbuf_max {
		803	$_[0]{wbuf_max} = $_[1];
		804	}
		805
		806	#############################################################################
		807
		808	=item $handle->timeout ($seconds)
		809
		810	=item $handle->rtimeout ($seconds)
		811
		812	=item $handle->wtimeout ($seconds)
		813
		814	Configures (or disables) the inactivity timeout.
		815
		816	The timeout will be checked instantly, so this method might destroy the
		817	handle before it returns.
		818
		819	=item $handle->timeout_reset
		820
		821	=item $handle->rtimeout_reset
		822
		823	=item $handle->wtimeout_reset
		824
		825	Reset the activity timeout, as if data was received or sent.
		826
		827	These methods are cheap to call.
		828
		829	=cut
		830
		831	for my $dir ("", "r", "w") {
		832	my $timeout = "${dir}timeout";
		833	my $tw = "_${dir}tw";
		834	my $on_timeout = "on_${dir}timeout";
		835	my $activity = "_${dir}activity";
		836	my $cb;
		837
		838	*$on_timeout = sub {
		839	$_[0]{$on_timeout} = $_[1];
		840	};
		841
		842	*$timeout = sub {
		843	my ($self, $new_value) = @_;
		844
		845	$new_value >= 0
		846	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		847
		848	$self->{$timeout} = $new_value;
		849	delete $self->{$tw}; &$cb;
		850	};
		851
		852	*{"${dir}timeout_reset"} = sub {
		853	$_[0]{$activity} = AE::now;
		854	};
		855
		856	# main workhorse:
		857	# reset the timeout watcher, as neccessary
		858	# also check for time-outs
		859	$cb = sub {
		860	my ($self) = @_;
		861
		862	if ($self->{$timeout} && $self->{fh}) {
		863	my $NOW = AE::now;
		864
		865	# when would the timeout trigger?
		866	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		867
		868	# now or in the past already?
		869	if ($after <= 0) {
		870	$self->{$activity} = $NOW;
		871
		872	if ($self->{$on_timeout}) {
		873	$self->{$on_timeout}($self);
		874	} else {
		875	$self->_error (Errno::ETIMEDOUT);
		876	}
		877
		878	# callback could have changed timeout value, optimise
		879	return unless $self->{$timeout};
		880
		881	# calculate new after
		882	$after = $self->{$timeout};
		883	}
		884
		885	Scalar::Util::weaken $self;
		886	return unless $self; # ->error could have destroyed $self
		887
		888	$self->{$tw} ||= AE::timer $after, 0, sub {
		889	delete $self->{$tw};
		890	$cb->($self);
		891	};
		892	} else {
		893	delete $self->{$tw};
		894	}
		895	}
		896	}
		897
257	#############################################################################	898	#############################################################################
258		899
259	=back	900	=back
260		901
261	=head2 WRITE QUEUE	902	=head2 WRITE QUEUE
…		…
265		906
266	The write queue is very simple: you can add data to its end, and	907	The write queue is very simple: you can add data to its end, and
267	AnyEvent::Handle will automatically try to get rid of it for you.	908	AnyEvent::Handle will automatically try to get rid of it for you.
268		909
269	When data could be written and the write buffer is shorter then the low	910	When data could be written and the write buffer is shorter then the low
270	water mark, the C<on_drain> callback will be invoked.	911	water mark, the C<on_drain> callback will be invoked once.
271		912
272	=over 4	913	=over 4
273		914
274	=item $handle->on_drain ($cb)	915	=item $handle->on_drain ($cb)
275		916
276	Sets the C<on_drain> callback or clears it (see the description of	917	Sets the C<on_drain> callback or clears it (see the description of
277	C<on_drain> in the constructor).	918	C<on_drain> in the constructor).
278		919
		920	This method may invoke callbacks (and therefore the handle might be
		921	destroyed after it returns).
		922
279	=cut	923	=cut
280		924
281	sub on_drain {	925	sub on_drain {
282	my ($self, $cb) = @_;	926	my ($self, $cb) = @_;
283		927
284	$self->{on_drain} = $cb;	928	$self->{on_drain} = $cb;
285		929
286	$cb->($self)	930	$cb->($self)
287	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	931	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
288	}	932	}
289		933
290	=item $handle->push_write ($data)	934	=item $handle->push_write ($data)
291		935
292	Queues the given scalar to be written. You can push as much data as you	936	Queues the given scalar to be written. You can push as much data as
293	want (only limited by the available memory), as C<AnyEvent::Handle>	937	you want (only limited by the available memory and C<wbuf_max>), as
294	buffers it independently of the kernel.	938	C<AnyEvent::Handle> buffers it independently of the kernel.
		939
		940	This method may invoke callbacks (and therefore the handle might be
		941	destroyed after it returns).
295		942
296	=cut	943	=cut
297		944
298	sub _drain_wbuf {	945	sub _drain_wbuf {
299	my ($self) = @_;	946	my ($self) = @_;
…		…
303	Scalar::Util::weaken $self;	950	Scalar::Util::weaken $self;
304		951
305	my $cb = sub {	952	my $cb = sub {
306	my $len = syswrite $self->{fh}, $self->{wbuf};	953	my $len = syswrite $self->{fh}, $self->{wbuf};
307		954
308	if ($len >= 0) {	955	if (defined $len) {
309	substr $self->{wbuf}, 0, $len, "";	956	substr $self->{wbuf}, 0, $len, "";
310		957
		958	$self->{_activity} = $self->{_wactivity} = AE::now;
		959
311	$self->{on_drain}($self)	960	$self->{on_drain}($self)
312	if $self->{low_water_mark} >= length $self->{wbuf}	961	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
313	&& $self->{on_drain};	962	&& $self->{on_drain};
314		963
315	delete $self->{_ww} unless length $self->{wbuf};	964	delete $self->{_ww} unless length $self->{wbuf};
316	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) {	965	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
317	$self->error;	966	$self->_error ($!, 1);
318	}	967	}
319	};	968	};
320		969
321	# try to write data immediately	970	# try to write data immediately
322	$cb->();	971	$cb->() unless $self->{autocork};
323		972
324	# if still data left in wbuf, we need to poll	973	# if still data left in wbuf, we need to poll
325	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	974	$self->{_ww} = AE::io $self->{fh}, 1, $cb
326	if length $self->{wbuf};	975	if length $self->{wbuf};
		976
		977	if (
		978	defined $self->{wbuf_max}
		979	&& $self->{wbuf_max} < length $self->{wbuf}
		980	) {
		981	$self->_error (Errno::ENOSPC, 1), return;
		982	}
327	};	983	};
328	}	984	}
329		985
330	our %WH;	986	our %WH;
331		987
		988	# deprecated
332	sub register_write_type($$) {	989	sub register_write_type($$) {
333	$WH{$_[0]} = $_[1];	990	$WH{$_[0]} = $_[1];
334	}	991	}
335		992
336	sub push_write {	993	sub push_write {
337	my $self = shift;	994	my $self = shift;
338		995
339	if (@_ > 1) {	996	if (@_ > 1) {
340	my $type = shift;	997	my $type = shift;
341		998
		999	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
342	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	1000	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
343	->($self, @_);	1001	->($self, @_);
344	}	1002	}
345		1003
		1004	# we downgrade here to avoid hard-to-track-down bugs,
		1005	# and diagnose the problem earlier and better.
		1006
346	if ($self->{filter_w}) {	1007	if ($self->{tls}) {
347	$self->{filter_w}->($self, \$_[0]);	1008	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		1009	&_dotls ($self) if $self->{fh};
348	} else {	1010	} else {
349	$self->{wbuf} .= $_[0];	1011	utf8::downgrade $self->{wbuf} .= $_[0];
350	$self->_drain_wbuf;	1012	$self->_drain_wbuf if $self->{fh};
351	}	1013	}
352	}	1014	}
353		1015
354	=item $handle->push_write (type => @args)	1016	=item $handle->push_write (type => @args)
355		1017
356	=item $handle->unshift_write (type => @args)
357
358	Instead of formatting your data yourself, you can also let this module do	1018	Instead of formatting your data yourself, you can also let this module
359	the job by specifying a type and type-specific arguments.	1019	do the job by specifying a type and type-specific arguments. You
		1020	can also specify the (fully qualified) name of a package, in which
		1021	case AnyEvent tries to load the package and then expects to find the
		1022	C<anyevent_write_type> function inside (see "custom write types", below).
360		1023
361	Predefined types are (if you have ideas for additional types, feel free to	1024	Predefined types are (if you have ideas for additional types, feel free to
362	drop by and tell us):	1025	drop by and tell us):
363		1026
364	=over 4	1027	=over 4
…		…
366	=item netstring => $string	1029	=item netstring => $string
367		1030
368	Formats the given value as netstring	1031	Formats the given value as netstring
369	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	1032	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
370		1033
371	=back
372
373	=cut	1034	=cut
374		1035
375	register_write_type netstring => sub {	1036	register_write_type netstring => sub {
376	my ($self, $string) = @_;	1037	my ($self, $string) = @_;
377		1038
378	sprintf "%d:%s,", (length $string), $string	1039	(length $string) . ":$string,"
379	};	1040	};
380		1041
		1042	=item packstring => $format, $data
		1043
		1044	An octet string prefixed with an encoded length. The encoding C<$format>
		1045	uses the same format as a Perl C<pack> format, but must specify a single
		1046	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1047	optional C<!>, C<< < >> or C<< > >> modifier).
		1048
		1049	=cut
		1050
		1051	register_write_type packstring => sub {
		1052	my ($self, $format, $string) = @_;
		1053
		1054	pack "$format/a*", $string
		1055	};
		1056
381	=item json => $array_or_hashref	1057	=item json => $array_or_hashref
382		1058
383	=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args)	1059	Encodes the given hash or array reference into a JSON object. Unless you
		1060	provide your own JSON object, this means it will be encoded to JSON text
		1061	in UTF-8.
384		1062
385	This function (not method) lets you add your own types to C<push_write>.	1063	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		1064	one end of a handle and read them at the other end without using any
		1065	additional framing.
		1066
		1067	The generated JSON text is guaranteed not to contain any newlines: While
		1068	this module doesn't need delimiters after or between JSON texts to be
		1069	able to read them, many other languages depend on that.
		1070
		1071	A simple RPC protocol that interoperates easily with other languages is
		1072	to send JSON arrays (or objects, although arrays are usually the better
		1073	choice as they mimic how function argument passing works) and a newline
		1074	after each JSON text:
		1075
		1076	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		1077	$handle->push_write ("\012");
		1078
		1079	An AnyEvent::Handle receiver would simply use the C<json> read type and
		1080	rely on the fact that the newline will be skipped as leading whitespace:
		1081
		1082	$handle->push_read (json => sub { my $array = $_[1]; ... });
		1083
		1084	Other languages could read single lines terminated by a newline and pass
		1085	this line into their JSON decoder of choice.
		1086
		1087	=item cbor => $perl_scalar
		1088
		1089	Encodes the given scalar into a CBOR value. Unless you provide your own
		1090	L<CBOR::XS> object, this means it will be encoded to a CBOR string not
		1091	using any extensions, if possible.
		1092
		1093	CBOR values are self-delimiting, so you can write CBOR at one end of
		1094	a handle and read them at the other end without using any additional
		1095	framing.
		1096
		1097	A simple nd very very fast RPC protocol that interoperates with
		1098	other languages is to send CBOR and receive CBOR values (arrays are
		1099	recommended):
		1100
		1101	$handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
		1102
		1103	An AnyEvent::Handle receiver would simply use the C<cbor> read type:
		1104
		1105	$handle->push_read (cbor => sub { my $array = $_[1]; ... });
		1106
		1107	=cut
		1108
		1109	sub json_coder() {
		1110	eval { require JSON::XS; JSON::XS->new->utf8 }
		1111	|| do { require JSON; JSON->new->utf8 }
		1112	}
		1113
		1114	register_write_type json => sub {
		1115	my ($self, $ref) = @_;
		1116
		1117	($self->{json} ||= json_coder)
		1118	->encode ($ref)
		1119	};
		1120
		1121	sub cbor_coder() {
		1122	require CBOR::XS;
		1123	CBOR::XS->new
		1124	}
		1125
		1126	register_write_type cbor => sub {
		1127	my ($self, $scalar) = @_;
		1128
		1129	($self->{cbor} ||= cbor_coder)
		1130	->encode ($scalar)
		1131	};
		1132
		1133	=item storable => $reference
		1134
		1135	Freezes the given reference using L<Storable> and writes it to the
		1136	handle. Uses the C<nfreeze> format.
		1137
		1138	=cut
		1139
		1140	register_write_type storable => sub {
		1141	my ($self, $ref) = @_;
		1142
		1143	require Storable unless $Storable::VERSION;
		1144
		1145	pack "w/a*", Storable::nfreeze ($ref)
		1146	};
		1147
		1148	=back
		1149
		1150	=item $handle->push_shutdown
		1151
		1152	Sometimes you know you want to close the socket after writing your data
		1153	before it was actually written. One way to do that is to replace your
		1154	C<on_drain> handler by a callback that shuts down the socket (and set
		1155	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1156	replaces the C<on_drain> callback with:
		1157
		1158	sub { shutdown $_[0]{fh}, 1 }
		1159
		1160	This simply shuts down the write side and signals an EOF condition to the
		1161	the peer.
		1162
		1163	You can rely on the normal read queue and C<on_eof> handling
		1164	afterwards. This is the cleanest way to close a connection.
		1165
		1166	This method may invoke callbacks (and therefore the handle might be
		1167	destroyed after it returns).
		1168
		1169	=cut
		1170
		1171	sub push_shutdown {
		1172	my ($self) = @_;
		1173
		1174	delete $self->{low_water_mark};
		1175	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1176	}
		1177
		1178	=item custom write types - Package::anyevent_write_type $handle, @args
		1179
		1180	Instead of one of the predefined types, you can also specify the name of
		1181	a package. AnyEvent will try to load the package and then expects to find
		1182	a function named C<anyevent_write_type> inside. If it isn't found, it
		1183	progressively tries to load the parent package until it either finds the
		1184	function (good) or runs out of packages (bad).
		1185
386	Whenever the given C<type> is used, C<push_write> will invoke the code	1186	Whenever the given C<type> is used, C<push_write> will the function with
387	reference with the handle object and the remaining arguments.	1187	the handle object and the remaining arguments.
388		1188
389	The code reference is supposed to return a single octet string that will	1189	The function is supposed to return a single octet string that will be
390	be appended to the write buffer.	1190	appended to the write buffer, so you can mentally treat this function as a
		1191	"arguments to on-the-wire-format" converter.
391		1192
392	Note that this is a function, and all types registered this way will be	1193	Example: implement a custom write type C<join> that joins the remaining
393	global, so try to use unique names.	1194	arguments using the first one.
		1195
		1196	$handle->push_write (My::Type => " ", 1,2,3);
		1197
		1198	# uses the following package, which can be defined in the "My::Type" or in
		1199	# the "My" modules to be auto-loaded, or just about anywhere when the
		1200	# My::Type::anyevent_write_type is defined before invoking it.
		1201
		1202	package My::Type;
		1203
		1204	sub anyevent_write_type {
		1205	my ($handle, $delim, @args) = @_;
		1206
		1207	join $delim, @args
		1208	}
394		1209
395	=cut	1210	=cut
396		1211
397	#############################################################################	1212	#############################################################################
398		1213
…		…
407	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1222	ways, the "simple" way, using only C<on_read> and the "complex" way, using
408	a queue.	1223	a queue.
409		1224
410	In the simple case, you just install an C<on_read> callback and whenever	1225	In the simple case, you just install an C<on_read> callback and whenever
411	new data arrives, it will be called. You can then remove some data (if	1226	new data arrives, it will be called. You can then remove some data (if
412	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	1227	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
413	or not.	1228	leave the data there if you want to accumulate more (e.g. when only a
		1229	partial message has been received so far), or change the read queue with
		1230	e.g. C<push_read>.
414		1231
415	In the more complex case, you want to queue multiple callbacks. In this	1232	In the more complex case, you want to queue multiple callbacks. In this
416	case, AnyEvent::Handle will call the first queued callback each time new	1233	case, AnyEvent::Handle will call the first queued callback each time new
417	data arrives and removes it when it has done its job (see C<push_read>,	1234	data arrives (also the first time it is queued) and remove it when it has
418	below).	1235	done its job (see C<push_read>, below).
419		1236
420	This way you can, for example, push three line-reads, followed by reading	1237	This way you can, for example, push three line-reads, followed by reading
421	a chunk of data, and AnyEvent::Handle will execute them in order.	1238	a chunk of data, and AnyEvent::Handle will execute them in order.
422		1239
423	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	1240	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
424	the specified number of bytes which give an XML datagram.	1241	the specified number of bytes which give an XML datagram.
425		1242
426	# in the default state, expect some header bytes	1243	# in the default state, expect some header bytes
427	$handle->on_read (sub {	1244	$handle->on_read (sub {
428	# some data is here, now queue the length-header-read (4 octets)	1245	# some data is here, now queue the length-header-read (4 octets)
429	shift->unshift_read_chunk (4, sub {	1246	shift->unshift_read (chunk => 4, sub {
430	# header arrived, decode	1247	# header arrived, decode
431	my $len = unpack "N", $_[1];	1248	my $len = unpack "N", $_[1];
432		1249
433	# now read the payload	1250	# now read the payload
434	shift->unshift_read_chunk ($len, sub {	1251	shift->unshift_read (chunk => $len, sub {
435	my $xml = $_[1];	1252	my $xml = $_[1];
436	# handle xml	1253	# handle xml
437	});	1254	});
438	});	1255	});
439	});	1256	});
440		1257
441	Example 2: Implement a client for a protocol that replies either with	1258	Example 2: Implement a client for a protocol that replies either with "OK"
442	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1259	and another line or "ERROR" for the first request that is sent, and 64
443	second request. Due tot he availability of a full queue, we can just	1260	bytes for the second request. Due to the availability of a queue, we can
444	pipeline sending both requests and manipulate the queue as necessary in	1261	just pipeline sending both requests and manipulate the queue as necessary
445	the callbacks:	1262	in the callbacks.
446		1263
447	# request one	1264	When the first callback is called and sees an "OK" response, it will
		1265	C<unshift> another line-read. This line-read will be queued I<before> the
		1266	64-byte chunk callback.
		1267
		1268	# request one, returns either "OK + extra line" or "ERROR"
448	$handle->push_write ("request 1\015\012");	1269	$handle->push_write ("request 1\015\012");
449		1270
450	# we expect "ERROR" or "OK" as response, so push a line read	1271	# we expect "ERROR" or "OK" as response, so push a line read
451	$handle->push_read_line (sub {	1272	$handle->push_read (line => sub {
452	# if we got an "OK", we have to _prepend_ another line,	1273	# if we got an "OK", we have to _prepend_ another line,
453	# so it will be read before the second request reads its 64 bytes	1274	# so it will be read before the second request reads its 64 bytes
454	# which are already in the queue when this callback is called	1275	# which are already in the queue when this callback is called
455	# we don't do this in case we got an error	1276	# we don't do this in case we got an error
456	if ($_[1] eq "OK") {	1277	if ($_[1] eq "OK") {
457	$_[0]->unshift_read_line (sub {	1278	$_[0]->unshift_read (line => sub {
458	my $response = $_[1];	1279	my $response = $_[1];
459	...	1280	...
460	});	1281	});
461	}	1282	}
462	});	1283	});
463		1284
464	# request two	1285	# request two, simply returns 64 octets
465	$handle->push_write ("request 2\015\012");	1286	$handle->push_write ("request 2\015\012");
466		1287
467	# simply read 64 bytes, always	1288	# simply read 64 bytes, always
468	$handle->push_read_chunk (64, sub {	1289	$handle->push_read (chunk => 64, sub {
469	my $response = $_[1];	1290	my $response = $_[1];
470	...	1291	...
471	});	1292	});
472		1293
473	=over 4	1294	=over 4
474		1295
475	=cut	1296	=cut
476		1297
477	sub _drain_rbuf {	1298	sub _drain_rbuf {
478	my ($self) = @_;	1299	my ($self) = @_;
		1300
		1301	# avoid recursion
		1302	return if $self->{_skip_drain_rbuf};
		1303	local $self->{_skip_drain_rbuf} = 1;
		1304
		1305	while () {
		1306	# we need to use a separate tls read buffer, as we must not receive data while
		1307	# we are draining the buffer, and this can only happen with TLS.
		1308	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1309	if exists $self->{_tls_rbuf};
		1310
		1311	my $len = length $self->{rbuf};
		1312
		1313	if (my $cb = shift @{ $self->{_queue} }) {
		1314	unless ($cb->($self)) {
		1315	# no progress can be made
		1316	# (not enough data and no data forthcoming)
		1317	$self->_error (Errno::EPIPE, 1), return
		1318	if $self->{_eof};
		1319
		1320	unshift @{ $self->{_queue} }, $cb;
		1321	last;
		1322	}
		1323	} elsif ($self->{on_read}) {
		1324	last unless $len;
		1325
		1326	$self->{on_read}($self);
		1327
		1328	if (
		1329	$len == length $self->{rbuf} # if no data has been consumed
		1330	&& !@{ $self->{_queue} } # and the queue is still empty
		1331	&& $self->{on_read} # but we still have on_read
		1332	) {
		1333	# no further data will arrive
		1334	# so no progress can be made
		1335	$self->_error (Errno::EPIPE, 1), return
		1336	if $self->{_eof};
		1337
		1338	last; # more data might arrive
		1339	}
		1340	} else {
		1341	# read side becomes idle
		1342	delete $self->{_rw} unless $self->{tls};
		1343	last;
		1344	}
		1345	}
		1346
		1347	if ($self->{_eof}) {
		1348	$self->{on_eof}
		1349	? $self->{on_eof}($self)
		1350	: $self->_error (0, 1, "Unexpected end-of-file");
		1351
		1352	return;
		1353	}
479		1354
480	if (	1355	if (
481	defined $self->{rbuf_max}	1356	defined $self->{rbuf_max}
482	&& $self->{rbuf_max} < length $self->{rbuf}	1357	&& $self->{rbuf_max} < length $self->{rbuf}
483	) {	1358	) {
484	$! = &Errno::ENOSPC;	1359	$self->_error (Errno::ENOSPC, 1), return;
485	$self->error;
486	}	1360	}
487		1361
488	return if $self->{in_drain};	1362	# may need to restart read watcher
489	local $self->{in_drain} = 1;	1363	unless ($self->{_rw}) {
490		1364	$self->start_read
491	while (my $len = length $self->{rbuf}) {	1365	if $self->{on_read} || @{ $self->{_queue} };
492	no strict 'refs';
493	if (my $cb = shift @{ $self->{_queue} }) {
494	unless ($cb->($self)) {
495	if ($self->{_eof}) {
496	# no progress can be made (not enough data and no data forthcoming)
497	$! = &Errno::EPIPE;
498	$self->error;
499	}
500
501	unshift @{ $self->{_queue} }, $cb;
502	return;
503	}
504	} elsif ($self->{on_read}) {
505	$self->{on_read}($self);
506
507	if (
508	$self->{_eof} # if no further data will arrive
509	&& $len == length $self->{rbuf} # and no data has been consumed
510	&& !@{ $self->{_queue} } # and the queue is still empty
511	&& $self->{on_read} # and we still want to read data
512	) {
513	# then no progress can be made
514	$! = &Errno::EPIPE;
515	$self->error;
516	}
517	} else {
518	# read side becomes idle
519	delete $self->{_rw};
520	return;
521	}
522	}
523
524	if ($self->{_eof}) {
525	$self->_shutdown;
526	$self->{on_eof}($self)
527	if $self->{on_eof};
528	}	1366	}
529	}	1367	}
530		1368
531	=item $handle->on_read ($cb)	1369	=item $handle->on_read ($cb)
532		1370
533	This replaces the currently set C<on_read> callback, or clears it (when	1371	This replaces the currently set C<on_read> callback, or clears it (when
534	the new callback is C<undef>). See the description of C<on_read> in the	1372	the new callback is C<undef>). See the description of C<on_read> in the
535	constructor.	1373	constructor.
536		1374
		1375	This method may invoke callbacks (and therefore the handle might be
		1376	destroyed after it returns).
		1377
537	=cut	1378	=cut
538		1379
539	sub on_read {	1380	sub on_read {
540	my ($self, $cb) = @_;	1381	my ($self, $cb) = @_;
541		1382
542	$self->{on_read} = $cb;	1383	$self->{on_read} = $cb;
		1384	$self->_drain_rbuf if $cb;
543	}	1385	}
544		1386
545	=item $handle->rbuf	1387	=item $handle->rbuf
546		1388
547	Returns the read buffer (as a modifiable lvalue).	1389	Returns the read buffer (as a modifiable lvalue). You can also access the
		1390	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1391	much faster, and no less clean).
548		1392
549	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1393	The only operation allowed on the read buffer (apart from looking at it)
550	you want.	1394	is removing data from its beginning. Otherwise modifying or appending to
		1395	it is not allowed and will lead to hard-to-track-down bugs.
551		1396
552	NOTE: The read buffer should only be used or modified if the C<on_read>,	1397	NOTE: The read buffer should only be used or modified in the C<on_read>
553	C<push_read> or C<unshift_read> methods are used. The other read methods	1398	callback or when C<push_read> or C<unshift_read> are used with a single
554	automatically manage the read buffer.	1399	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1400	will manage the read buffer on their own.
555		1401
556	=cut	1402	=cut
557		1403
558	sub rbuf : lvalue {	1404	sub rbuf : lvalue {
559	$_[0]{rbuf}	1405	$_[0]{rbuf}
…		…
576		1422
577	If enough data was available, then the callback must remove all data it is	1423	If enough data was available, then the callback must remove all data it is
578	interested in (which can be none at all) and return a true value. After returning	1424	interested in (which can be none at all) and return a true value. After returning
579	true, it will be removed from the queue.	1425	true, it will be removed from the queue.
580		1426
		1427	These methods may invoke callbacks (and therefore the handle might be
		1428	destroyed after it returns).
		1429
581	=cut	1430	=cut
582		1431
583	our %RH;	1432	our %RH;
584		1433
585	sub register_read_type($$) {	1434	sub register_read_type($$) {
…		…
591	my $cb = pop;	1440	my $cb = pop;
592		1441
593	if (@_) {	1442	if (@_) {
594	my $type = shift;	1443	my $type = shift;
595		1444
		1445	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
596	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1446	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
597	->($self, $cb, @_);	1447	->($self, $cb, @_);
598	}	1448	}
599		1449
600	push @{ $self->{_queue} }, $cb;	1450	push @{ $self->{_queue} }, $cb;
601	$self->_drain_rbuf;	1451	$self->_drain_rbuf;
…		…
606	my $cb = pop;	1456	my $cb = pop;
607		1457
608	if (@_) {	1458	if (@_) {
609	my $type = shift;	1459	my $type = shift;
610		1460
		1461	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
611	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1462	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
612	->($self, $cb, @_);	1463	->($self, $cb, @_);
613	}	1464	}
614
615		1465
616	unshift @{ $self->{_queue} }, $cb;	1466	unshift @{ $self->{_queue} }, $cb;
617	$self->_drain_rbuf;	1467	$self->_drain_rbuf;
618	}	1468	}
619		1469
…		…
621		1471
622	=item $handle->unshift_read (type => @args, $cb)	1472	=item $handle->unshift_read (type => @args, $cb)
623		1473
624	Instead of providing a callback that parses the data itself you can chose	1474	Instead of providing a callback that parses the data itself you can chose
625	between a number of predefined parsing formats, for chunks of data, lines	1475	between a number of predefined parsing formats, for chunks of data, lines
626	etc.	1476	etc. You can also specify the (fully qualified) name of a package, in
		1477	which case AnyEvent tries to load the package and then expects to find the
		1478	C<anyevent_read_type> function inside (see "custom read types", below).
627		1479
628	Predefined types are (if you have ideas for additional types, feel free to	1480	Predefined types are (if you have ideas for additional types, feel free to
629	drop by and tell us):	1481	drop by and tell us):
630		1482
631	=over 4	1483	=over 4
632		1484
633	=item chunk => $octets, $cb->($self, $data)	1485	=item chunk => $octets, $cb->($handle, $data)
634		1486
635	Invoke the callback only once C<$octets> bytes have been read. Pass the	1487	Invoke the callback only once C<$octets> bytes have been read. Pass the
636	data read to the callback. The callback will never be called with less	1488	data read to the callback. The callback will never be called with less
637	data.	1489	data.
638		1490
639	Example: read 2 bytes.	1491	Example: read 2 bytes.
640		1492
641	$handle->push_read (chunk => 2, sub {	1493	$handle->push_read (chunk => 2, sub {
642	warn "yay ", unpack "H*", $_[1];	1494	say "yay " . unpack "H*", $_[1];
643	});	1495	});
644		1496
645	=cut	1497	=cut
646		1498
647	register_read_type chunk => sub {	1499	register_read_type chunk => sub {
…		…
652	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1504	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
653	1	1505	1
654	}	1506	}
655	};	1507	};
656		1508
657	# compatibility with older API
658	sub push_read_chunk {
659	$_[0]->push_read (chunk => $_[1], $_[2]);
660	}
661
662	sub unshift_read_chunk {
663	$_[0]->unshift_read (chunk => $_[1], $_[2]);
664	}
665
666	=item line => [$eol, ]$cb->($self, $line, $eol)	1509	=item line => [$eol, ]$cb->($handle, $line, $eol)
667		1510
668	The callback will be called only once a full line (including the end of	1511	The callback will be called only once a full line (including the end of
669	line marker, C<$eol>) has been read. This line (excluding the end of line	1512	line marker, C<$eol>) has been read. This line (excluding the end of line
670	marker) will be passed to the callback as second argument (C<$line>), and	1513	marker) will be passed to the callback as second argument (C<$line>), and
671	the end of line marker as the third argument (C<$eol>).	1514	the end of line marker as the third argument (C<$eol>).
…		…
685	=cut	1528	=cut
686		1529
687	register_read_type line => sub {	1530	register_read_type line => sub {
688	my ($self, $cb, $eol) = @_;	1531	my ($self, $cb, $eol) = @_;
689		1532
690	$eol = qr|(\015?\012)| if @_ < 3;	1533	if (@_ < 3) {
		1534	# this is faster then the generic code below
		1535	sub {
		1536	(my $pos = index $_[0]{rbuf}, "\012") >= 0
		1537	or return;
		1538
		1539	(my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
		1540	$cb->($_[0], $str, "$1");
		1541	1
		1542	}
		1543	} else {
691	$eol = quotemeta $eol unless ref $eol;	1544	$eol = quotemeta $eol unless ref $eol;
692	$eol = qr|^(.*?)($eol)|s;	1545	$eol = qr|^(.*?)($eol)|s;
693		1546
694	sub {	1547	sub {
695	$_[0]{rbuf} =~ s/$eol// or return;	1548	$_[0]{rbuf} =~ s/$eol// or return;
696		1549
697	$cb->($_[0], $1, $2);	1550	$cb->($_[0], "$1", "$2");
		1551	1
698	1	1552	}
699	}	1553	}
700	};	1554	};
701		1555
702	# compatibility with older API
703	sub push_read_line {
704	my $self = shift;
705	$self->push_read (line => @_);
706	}
707
708	sub unshift_read_line {
709	my $self = shift;
710	$self->unshift_read (line => @_);
711	}
712
713	=item netstring => $cb->($string)
714
715	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
716
717	Throws an error with C<$!> set to EBADMSG on format violations.
718
719	=cut
720
721	register_read_type netstring => sub {
722	my ($self, $cb) = @_;
723
724	sub {
725	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
726	if ($_[0]{rbuf} =~ /[^0-9]/) {
727	$! = &Errno::EBADMSG;
728	$self->error;
729	}
730	return;
731	}
732
733	my $len = $1;
734
735	$self->unshift_read (chunk => $len, sub {
736	my $string = $_[1];
737	$_[0]->unshift_read (chunk => 1, sub {
738	if ($_[1] eq ",") {
739	$cb->($_[0], $string);
740	} else {
741	$! = &Errno::EBADMSG;
742	$self->error;
743	}
744	});
745	});
746
747	1
748	}
749	};
750
751	=item regex => $accept[, $reject[, $skip], $cb->($data)	1556	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
752		1557
753	Makes a regex match against the regex object C<$accept> and returns	1558	Makes a regex match against the regex object C<$accept> and returns
754	everything up to and including the match.	1559	everything up to and including the match.
755		1560
756	Example: read a single line terminated by '\n'.	1561	Example: read a single line terminated by '\n'.
…		…
772	the receive buffer when neither C<$accept> nor C<$reject> match,	1577	the receive buffer when neither C<$accept> nor C<$reject> match,
773	and everything preceding and including the match will be accepted	1578	and everything preceding and including the match will be accepted
774	unconditionally. This is useful to skip large amounts of data that you	1579	unconditionally. This is useful to skip large amounts of data that you
775	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1580	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
776	have to start matching from the beginning. This is purely an optimisation	1581	have to start matching from the beginning. This is purely an optimisation
777	and is usually worth only when you expect more than a few kilobytes.	1582	and is usually worth it only when you expect more than a few kilobytes.
778		1583
779	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1584	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
780	expect the header to be very large (it isn't in practise, but...), we use	1585	expect the header to be very large (it isn't in practice, but...), we use
781	a skip regex to skip initial portions. The skip regex is tricky in that	1586	a skip regex to skip initial portions. The skip regex is tricky in that
782	it only accepts something not ending in either \015 or \012, as these are	1587	it only accepts something not ending in either \015 or \012, as these are
783	required for the accept regex.	1588	required for the accept regex.
784		1589
785	$handle->push_read (regex =>	1590	$handle->push_read (regex =>
…		…
798		1603
799	sub {	1604	sub {
800	# accept	1605	# accept
801	if ($$rbuf =~ $accept) {	1606	if ($$rbuf =~ $accept) {
802	$data .= substr $$rbuf, 0, $+[0], "";	1607	$data .= substr $$rbuf, 0, $+[0], "";
803	$cb->($self, $data);	1608	$cb->($_[0], $data);
804	return 1;	1609	return 1;
805	}	1610	}
806		1611
807	# reject	1612	# reject
808	if ($reject && $$rbuf =~ $reject) {	1613	if ($reject && $$rbuf =~ $reject) {
809	$! = &Errno::EBADMSG;	1614	$_[0]->_error (Errno::EBADMSG);
810	$self->error;
811	}	1615	}
812		1616
813	# skip	1617	# skip
814	if ($skip && $$rbuf =~ $skip) {	1618	if ($skip && $$rbuf =~ $skip) {
815	$data .= substr $$rbuf, 0, $+[0], "";	1619	$data .= substr $$rbuf, 0, $+[0], "";
…		…
817		1621
818	()	1622	()
819	}	1623	}
820	};	1624	};
821		1625
		1626	=item netstring => $cb->($handle, $string)
		1627
		1628	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1629
		1630	Throws an error with C<$!> set to EBADMSG on format violations.
		1631
		1632	=cut
		1633
		1634	register_read_type netstring => sub {
		1635	my ($self, $cb) = @_;
		1636
		1637	sub {
		1638	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1639	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1640	$_[0]->_error (Errno::EBADMSG);
		1641	}
		1642	return;
		1643	}
		1644
		1645	my $len = $1;
		1646
		1647	$_[0]->unshift_read (chunk => $len, sub {
		1648	my $string = $_[1];
		1649	$_[0]->unshift_read (chunk => 1, sub {
		1650	if ($_[1] eq ",") {
		1651	$cb->($_[0], $string);
		1652	} else {
		1653	$_[0]->_error (Errno::EBADMSG);
		1654	}
		1655	});
		1656	});
		1657
		1658	1
		1659	}
		1660	};
		1661
		1662	=item packstring => $format, $cb->($handle, $string)
		1663
		1664	An octet string prefixed with an encoded length. The encoding C<$format>
		1665	uses the same format as a Perl C<pack> format, but must specify a single
		1666	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1667	optional C<!>, C<< < >> or C<< > >> modifier).
		1668
		1669	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1670	EPP uses a prefix of C<N> (4 octtes).
		1671
		1672	Example: read a block of data prefixed by its length in BER-encoded
		1673	format (very efficient).
		1674
		1675	$handle->push_read (packstring => "w", sub {
		1676	my ($handle, $data) = @_;
		1677	});
		1678
		1679	=cut
		1680
		1681	register_read_type packstring => sub {
		1682	my ($self, $cb, $format) = @_;
		1683
		1684	sub {
		1685	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1686	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1687	or return;
		1688
		1689	$format = length pack $format, $len;
		1690
		1691	# bypass unshift if we already have the remaining chunk
		1692	if ($format + $len <= length $_[0]{rbuf}) {
		1693	my $data = substr $_[0]{rbuf}, $format, $len;
		1694	substr $_[0]{rbuf}, 0, $format + $len, "";
		1695	$cb->($_[0], $data);
		1696	} else {
		1697	# remove prefix
		1698	substr $_[0]{rbuf}, 0, $format, "";
		1699
		1700	# read remaining chunk
		1701	$_[0]->unshift_read (chunk => $len, $cb);
		1702	}
		1703
		1704	1
		1705	}
		1706	};
		1707
		1708	=item json => $cb->($handle, $hash_or_arrayref)
		1709
		1710	Reads a JSON object or array, decodes it and passes it to the
		1711	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1712
		1713	If a C<json> object was passed to the constructor, then that will be used
		1714	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1715
		1716	This read type uses the incremental parser available with JSON version
		1717	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1718	dependency on your own: this module will load the JSON module, but
		1719	AnyEvent does not depend on it itself.
		1720
		1721	Since JSON texts are fully self-delimiting, the C<json> read and write
		1722	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1723	the C<json> write type description, above, for an actual example.
		1724
		1725	=cut
		1726
		1727	register_read_type json => sub {
		1728	my ($self, $cb) = @_;
		1729
		1730	my $json = $self->{json} ||= json_coder;
		1731
		1732	my $data;
		1733
		1734	sub {
		1735	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
		1736
		1737	if ($ref) {
		1738	$_[0]{rbuf} = $json->incr_text;
		1739	$json->incr_text = "";
		1740	$cb->($_[0], $ref);
		1741
		1742	1
		1743	} elsif ($@) {
		1744	# error case
		1745	$json->incr_skip;
		1746
		1747	$_[0]{rbuf} = $json->incr_text;
		1748	$json->incr_text = "";
		1749
		1750	$_[0]->_error (Errno::EBADMSG);
		1751
		1752	()
		1753	} else {
		1754	$_[0]{rbuf} = "";
		1755
		1756	()
		1757	}
		1758	}
		1759	};
		1760
		1761	=item cbor => $cb->($handle, $scalar)
		1762
		1763	Reads a CBOR value, decodes it and passes it to the callback. When a parse
		1764	error occurs, an C<EBADMSG> error will be raised.
		1765
		1766	If a L<CBOR::XS> object was passed to the constructor, then that will be
		1767	used for the final decode, otherwise it will create a CBOR coder without
		1768	enabling any options.
		1769
		1770	You have to provide a dependency to L<CBOR::XS> on your own: this module
		1771	will load the L<CBOR::XS> module, but AnyEvent does not depend on it
		1772	itself.
		1773
		1774	Since CBOR values are fully self-delimiting, the C<cbor> read and write
		1775	types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
		1776	the C<cbor> write type description, above, for an actual example.
		1777
		1778	=cut
		1779
		1780	register_read_type cbor => sub {
		1781	my ($self, $cb) = @_;
		1782
		1783	my $cbor = $self->{cbor} ||= cbor_coder;
		1784
		1785	my $data;
		1786
		1787	sub {
		1788	my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
		1789
		1790	if (@value) {
		1791	$cb->($_[0], @value);
		1792
		1793	1
		1794	} elsif ($@) {
		1795	# error case
		1796	$cbor->incr_reset;
		1797
		1798	$_[0]->_error (Errno::EBADMSG);
		1799
		1800	()
		1801	} else {
		1802	()
		1803	}
		1804	}
		1805	};
		1806
		1807	=item storable => $cb->($handle, $ref)
		1808
		1809	Deserialises a L<Storable> frozen representation as written by the
		1810	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1811	data).
		1812
		1813	Raises C<EBADMSG> error if the data could not be decoded.
		1814
		1815	=cut
		1816
		1817	register_read_type storable => sub {
		1818	my ($self, $cb) = @_;
		1819
		1820	require Storable unless $Storable::VERSION;
		1821
		1822	sub {
		1823	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1824	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1825	or return;
		1826
		1827	my $format = length pack "w", $len;
		1828
		1829	# bypass unshift if we already have the remaining chunk
		1830	if ($format + $len <= length $_[0]{rbuf}) {
		1831	my $data = substr $_[0]{rbuf}, $format, $len;
		1832	substr $_[0]{rbuf}, 0, $format + $len, "";
		1833
		1834	eval { $cb->($_[0], Storable::thaw ($data)); 1 }
		1835	or return $_[0]->_error (Errno::EBADMSG);
		1836	} else {
		1837	# remove prefix
		1838	substr $_[0]{rbuf}, 0, $format, "";
		1839
		1840	# read remaining chunk
		1841	$_[0]->unshift_read (chunk => $len, sub {
		1842	eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
		1843	or $_[0]->_error (Errno::EBADMSG);
		1844	});
		1845	}
		1846
		1847	1
		1848	}
		1849	};
		1850
		1851	=item tls_detect => $cb->($handle, $detect, $major, $minor)
		1852
		1853	Checks the input stream for a valid SSL or TLS handshake TLSPaintext
		1854	record without consuming anything. Only SSL version 3 or higher
		1855	is handled, up to the fictituous protocol 4.x (but both SSL3+ and
		1856	SSL2-compatible framing is supported).
		1857
		1858	If it detects that the input data is likely TLS, it calls the callback
		1859	with a true value for C<$detect> and the (on-wire) TLS version as second
		1860	and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
		1861	3.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
		1862	be definitely not TLS, it calls the callback with a false value for
		1863	C<$detect>.
		1864
		1865	The callback could use this information to decide whether or not to start
		1866	TLS negotiation.
		1867
		1868	In all cases the data read so far is passed to the following read
		1869	handlers.
		1870
		1871	Usually you want to use the C<tls_autostart> read type instead.
		1872
		1873	If you want to design a protocol that works in the presence of TLS
		1874	dtection, make sure that any non-TLS data doesn't start with the octet 22
		1875	(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
		1876	read type does are a bit more strict, but might losen in the future to
		1877	accomodate protocol changes.
		1878
		1879	This read type does not rely on L<AnyEvent::TLS> (and thus, not on
		1880	L<Net::SSLeay>).
		1881
		1882	=item tls_autostart => $tls[, $tls_ctx]
		1883
		1884	Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
		1885	to start tls by calling C<starttls> with the given arguments.
		1886
		1887	In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
		1888	been configured to accept, as servers do not normally send a handshake on
		1889	their own and ths cannot be detected in this way.
		1890
		1891	See C<tls_detect> above for more details.
		1892
		1893	Example: give the client a chance to start TLS before accepting a text
		1894	line.
		1895
		1896	$hdl->push_read (tls_detect => "accept");
		1897	$hdl->push_read (line => sub {
		1898	print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
		1899	});
		1900
		1901	=cut
		1902
		1903	register_read_type tls_detect => sub {
		1904	my ($self, $cb) = @_;
		1905
		1906	sub {
		1907	# this regex matches a full or partial tls record
		1908	if (
		1909	# ssl3+: type(22=handshake) major(=3) minor(any) length_hi
		1910	$self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
		1911	# ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
		1912	or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
		1913	) {
		1914	return if 3 != length $1; # partial match, can't decide yet
		1915
		1916	# full match, valid TLS record
		1917	my ($major, $minor) = unpack "CC", $1;
		1918	$cb->($self, "accept", $major + $minor * 0.1);
		1919	} else {
		1920	# mismatch == guaranteed not TLS
		1921	$cb->($self, undef);
		1922	}
		1923
		1924	1
		1925	}
		1926	};
		1927
		1928	register_read_type tls_autostart => sub {
		1929	my ($self, @tls) = @_;
		1930
		1931	$RH{tls_detect}($self, sub {
		1932	return unless $_[1];
		1933	$_[0]->starttls (@tls);
		1934	})
		1935	};
		1936
822	=back	1937	=back
823		1938
824	=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args)	1939	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
825		1940
826	This function (not method) lets you add your own types to C<push_read>.	1941	Instead of one of the predefined types, you can also specify the name
		1942	of a package. AnyEvent will try to load the package and then expects to
		1943	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1944	progressively tries to load the parent package until it either finds the
		1945	function (good) or runs out of packages (bad).
827		1946
828	Whenever the given C<type> is used, C<push_read> will invoke the code	1947	Whenever this type is used, C<push_read> will invoke the function with the
829	reference with the handle object, the callback and the remaining	1948	handle object, the original callback and the remaining arguments.
830	arguments.
831		1949
832	The code reference is supposed to return a callback (usually a closure)	1950	The function is supposed to return a callback (usually a closure) that
833	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1951	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1952	mentally treat the function as a "configurable read type to read callback"
		1953	converter.
834		1954
835	It should invoke the passed callback when it is done reading (remember to	1955	It should invoke the original callback when it is done reading (remember
836	pass C<$self> as first argument as all other callbacks do that).	1956	to pass C<$handle> as first argument as all other callbacks do that,
		1957	although there is no strict requirement on this).
837		1958
838	Note that this is a function, and all types registered this way will be
839	global, so try to use unique names.
840
841	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1959	For examples, see the source of this module (F<perldoc -m
842	search for C<register_read_type>)).	1960	AnyEvent::Handle>, search for C<register_read_type>)).
843		1961
844	=item $handle->stop_read	1962	=item $handle->stop_read
845		1963
846	=item $handle->start_read	1964	=item $handle->start_read
847		1965
848	In rare cases you actually do not want to read anything from the	1966	In rare cases you actually do not want to read anything from the
849	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1967	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
850	any queued callbacks will be executed then. To start reading again, call	1968	any queued callbacks will be executed then. To start reading again, call
851	C<start_read>.	1969	C<start_read>.
852		1970
		1971	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1972	you change the C<on_read> callback or push/unshift a read callback, and it
		1973	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1974	there are any read requests in the queue.
		1975
		1976	In older versions of this module (<= 5.3), these methods had no effect,
		1977	as TLS does not support half-duplex connections. In current versions they
		1978	work as expected, as this behaviour is required to avoid certain resource
		1979	attacks, where the program would be forced to read (and buffer) arbitrary
		1980	amounts of data before being able to send some data. The drawback is that
		1981	some readings of the the SSL/TLS specifications basically require this
		1982	attack to be working, as SSL/TLS implementations might stall sending data
		1983	during a rehandshake.
		1984
		1985	As a guideline, during the initial handshake, you should not stop reading,
		1986	and as a client, it might cause problems, depending on your application.
		1987
853	=cut	1988	=cut
854		1989
855	sub stop_read {	1990	sub stop_read {
856	my ($self) = @_;	1991	my ($self) = @_;
857		1992
…		…
859	}	1994	}
860		1995
861	sub start_read {	1996	sub start_read {
862	my ($self) = @_;	1997	my ($self) = @_;
863		1998
864	unless ($self->{_rw} || $self->{_eof}) {	1999	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
865	Scalar::Util::weaken $self;	2000	Scalar::Util::weaken $self;
866		2001
867	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	2002	$self->{_rw} = AE::io $self->{fh}, 0, sub {
868	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	2003	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
869	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	2004	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
870		2005
871	if ($len > 0) {	2006	if ($len > 0) {
872	$self->{filter_r}	2007	$self->{_activity} = $self->{_ractivity} = AE::now;
873	? $self->{filter_r}->($self, $rbuf)	2008
		2009	if ($self->{tls}) {
		2010	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		2011
		2012	&_dotls ($self);
		2013	} else {
874	: $self->_drain_rbuf;	2014	$self->_drain_rbuf;
		2015	}
		2016
		2017	if ($len == $self->{read_size}) {
		2018	$self->{read_size} *= 2;
		2019	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		2020	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		2021	}
875		2022
876	} elsif (defined $len) {	2023	} elsif (defined $len) {
877	delete $self->{_rw};	2024	delete $self->{_rw};
878	$self->{_eof} = 1;	2025	$self->{_eof} = 1;
879	$self->_drain_rbuf;	2026	$self->_drain_rbuf;
880		2027
881	} elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) {	2028	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
882	return $self->error;	2029	return $self->_error ($!, 1);
883	}	2030	}
884	});	2031	};
885	}	2032	}
886	}	2033	}
887		2034
		2035	our $ERROR_SYSCALL;
		2036	our $ERROR_WANT_READ;
		2037
		2038	sub _tls_error {
		2039	my ($self, $err) = @_;
		2040
		2041	return $self->_error ($!, 1)
		2042	if $err == Net::SSLeay::ERROR_SYSCALL ();
		2043
		2044	my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		2045
		2046	# reduce error string to look less scary
		2047	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		2048
		2049	if ($self->{_on_starttls}) {
		2050	(delete $self->{_on_starttls})->($self, undef, $err);
		2051	&_freetls;
		2052	} else {
		2053	&_freetls;
		2054	$self->_error (Errno::EPROTO, 1, $err);
		2055	}
		2056	}
		2057
		2058	# poll the write BIO and send the data if applicable
		2059	# also decode read data if possible
		2060	# this is basiclaly our TLS state machine
		2061	# more efficient implementations are possible with openssl,
		2062	# but not with the buggy and incomplete Net::SSLeay.
888	sub _dotls {	2063	sub _dotls {
889	my ($self) = @_;	2064	my ($self) = @_;
890		2065
		2066	my $tmp;
		2067
891	if (length $self->{_tls_wbuf}) {	2068	while (length $self->{_tls_wbuf}) {
892	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	2069	if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
893	substr $self->{_tls_wbuf}, 0, $len, "";	2070	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		2071
		2072	return $self->_tls_error ($tmp)
		2073	if $tmp != $ERROR_WANT_READ
		2074	&& ($tmp != $ERROR_SYSCALL || $!);
		2075
		2076	last;
894	}	2077	}
895	}
896		2078
		2079	substr $self->{_tls_wbuf}, 0, $tmp, "";
		2080	}
		2081
		2082	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		2083	unless (length $tmp) {
		2084	$self->{_on_starttls}
		2085	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		2086	&_freetls;
		2087
		2088	if ($self->{on_stoptls}) {
		2089	$self->{on_stoptls}($self);
		2090	return;
		2091	} else {
		2092	# let's treat SSL-eof as we treat normal EOF
		2093	delete $self->{_rw};
		2094	$self->{_eof} = 1;
		2095	}
		2096	}
		2097
		2098	$self->{_tls_rbuf} .= $tmp;
		2099	$self->_drain_rbuf;
		2100	$self->{tls} or return; # tls session might have gone away in callback
		2101	}
		2102
		2103	$tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
		2104	return $self->_tls_error ($tmp)
		2105	if $tmp != $ERROR_WANT_READ
		2106	&& ($tmp != $ERROR_SYSCALL || $!);
		2107
897	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	2108	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
898	$self->{wbuf} .= $buf;	2109	$self->{wbuf} .= $tmp;
899	$self->_drain_wbuf;	2110	$self->_drain_wbuf;
		2111	$self->{tls} or return; # tls session might have gone away in callback
900	}	2112	}
901		2113
902	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {	2114	$self->{_on_starttls}
903	$self->{rbuf} .= $buf;	2115	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
904	$self->_drain_rbuf;	2116	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
905	}
906
907	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
908
909	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
910	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
911	$self->error;
912	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
913	$! = &Errno::EIO;
914	$self->error;
915	}
916
917	# all others are fine for our purposes
918	}
919	}	2117	}
920		2118
921	=item $handle->starttls ($tls[, $tls_ctx])	2119	=item $handle->starttls ($tls[, $tls_ctx])
922		2120
923	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	2121	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
924	object is created, you can also do that at a later time by calling	2122	object is created, you can also do that at a later time by calling
925	C<starttls>.	2123	C<starttls>. See the C<tls> constructor argument for general info.
		2124
		2125	Starting TLS is currently an asynchronous operation - when you push some
		2126	write data and then call C<< ->starttls >> then TLS negotiation will start
		2127	immediately, after which the queued write data is then sent. This might
		2128	change in future versions, so best make sure you have no outstanding write
		2129	data when calling this method.
926		2130
927	The first argument is the same as the C<tls> constructor argument (either	2131	The first argument is the same as the C<tls> constructor argument (either
928	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	2132	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
929		2133
930	The second argument is the optional C<Net::SSLeay::CTX> object that is	2134	The second argument is the optional C<AnyEvent::TLS> object that is used
931	used when AnyEvent::Handle has to create its own TLS connection object.	2135	when AnyEvent::Handle has to create its own TLS connection object, or
		2136	a hash reference with C<< key => value >> pairs that will be used to
		2137	construct a new context.
932		2138
933	The TLS connection object will end up in C<< $handle->{tls} >> after this	2139	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
934	call and can be used or changed to your liking. Note that the handshake	2140	context in C<< $handle->{tls_ctx} >> after this call and can be used or
935	might have already started when this function returns.	2141	changed to your liking. Note that the handshake might have already started
		2142	when this function returns.
936		2143
937	=cut	2144	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		2145	handshakes on the same stream. It is best to not attempt to use the
		2146	stream after stopping TLS.
938		2147
939	# TODO: maybe document...	2148	This method may invoke callbacks (and therefore the handle might be
		2149	destroyed after it returns).
		2150
		2151	=cut
		2152
		2153	our %TLS_CACHE; #TODO not yet documented, should we?
		2154
940	sub starttls {	2155	sub starttls {
941	my ($self, $ssl, $ctx) = @_;	2156	my ($self, $tls, $ctx) = @_;
942		2157
943	$self->stoptls;	2158	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		2159	if $self->{tls};
944		2160
945	if ($ssl eq "accept") {	2161	unless (defined $AnyEvent::TLS::VERSION) {
946	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2162	eval {
947	Net::SSLeay::set_accept_state ($ssl);	2163	require Net::SSLeay;
948	} elsif ($ssl eq "connect") {	2164	require AnyEvent::TLS;
949	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2165	1
950	Net::SSLeay::set_connect_state ($ssl);	2166	} or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
		2167	}
		2168
		2169	$self->{tls} = $tls;
		2170	$self->{tls_ctx} = $ctx if @_ > 2;
		2171
		2172	return unless $self->{fh};
		2173
		2174	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		2175	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		2176
		2177	$tls = delete $self->{tls};
		2178	$ctx = $self->{tls_ctx};
		2179
		2180	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		2181
		2182	if ("HASH" eq ref $ctx) {
		2183	if ($ctx->{cache}) {
		2184	my $key = $ctx+0;
		2185	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		2186	} else {
		2187	$ctx = new AnyEvent::TLS %$ctx;
		2188	}
		2189	}
951	}	2190
952		2191	$self->{tls_ctx} = $ctx || TLS_CTX ();
953	$self->{tls} = $ssl;	2192	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
954		2193
955	# basically, this is deep magic (because SSL_read should have the same issues)	2194	# basically, this is deep magic (because SSL_read should have the same issues)
956	# but the openssl maintainers basically said: "trust us, it just works".	2195	# but the openssl maintainers basically said: "trust us, it just works".
957	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	2196	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
958	# and mismaintained ssleay-module doesn't even offer them).	2197	# and mismaintained ssleay-module doesn't even offer them).
959	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	2198	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		2199	#
		2200	# in short: this is a mess.
		2201	#
		2202	# note that we do not try to keep the length constant between writes as we are required to do.
		2203	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		2204	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		2205	# have identity issues in that area.
960	Net::SSLeay::CTX_set_mode ($self->{tls},	2206	# Net::SSLeay::CTX_set_mode ($ssl,
961	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2207	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
962	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2208	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		2209	Net::SSLeay::CTX_set_mode ($tls, 1|2);
963		2210
964	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2211	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
965	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2212	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
966		2213
		2214	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2215	$self->{rbuf} = "";
		2216
967	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	2217	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
968		2218
969	$self->{filter_w} = sub {	2219	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
970	$_[0]{_tls_wbuf} .= ${$_[1]};	2220	if $self->{on_starttls};
971	&_dotls;	2221
972	};	2222	&_dotls; # need to trigger the initial handshake
973	$self->{filter_r} = sub {	2223	$self->start_read; # make sure we actually do read
974	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
975	&_dotls;
976	};
977	}	2224	}
978		2225
979	=item $handle->stoptls	2226	=item $handle->stoptls
980		2227
981	Destroys the SSL connection, if any. Partial read or write data will be	2228	Shuts down the SSL connection - this makes a proper EOF handshake by
982	lost.	2229	sending a close notify to the other side, but since OpenSSL doesn't
		2230	support non-blocking shut downs, it is not guaranteed that you can re-use
		2231	the stream afterwards.
		2232
		2233	This method may invoke callbacks (and therefore the handle might be
		2234	destroyed after it returns).
983		2235
984	=cut	2236	=cut
985		2237
986	sub stoptls {	2238	sub stoptls {
987	my ($self) = @_;	2239	my ($self) = @_;
988		2240
989	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	2241	if ($self->{tls} && $self->{fh}) {
		2242	Net::SSLeay::shutdown ($self->{tls});
990		2243
991	delete $self->{_rbio};	2244	&_dotls;
992	delete $self->{_wbio};	2245
993	delete $self->{_tls_wbuf};	2246	# # we don't give a shit. no, we do, but we can't. no...#d#
994	delete $self->{filter_r};	2247	# # we, we... have to use openssl :/#d#
995	delete $self->{filter_w};	2248	# &_freetls;#d#
		2249	}
996	}	2250	}
		2251
		2252	sub _freetls {
		2253	my ($self) = @_;
		2254
		2255	return unless $self->{tls};
		2256
		2257	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2258	if $self->{tls} > 0;
		2259
		2260	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		2261	}
		2262
		2263	=item $handle->resettls
		2264
		2265	This rarely-used method simply resets and TLS state on the handle, usually
		2266	causing data loss.
		2267
		2268	One case where it may be useful is when you want to skip over the data in
		2269	the stream but you are not interested in interpreting it, so data loss is
		2270	no concern.
		2271
		2272	=cut
		2273
		2274	*resettls = \&_freetls;
997		2275
998	sub DESTROY {	2276	sub DESTROY {
999	my $self = shift;	2277	my ($self) = @_;
1000		2278
1001	$self->stoptls;	2279	&_freetls;
		2280
		2281	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		2282
		2283	if ($linger && length $self->{wbuf} && $self->{fh}) {
		2284	my $fh = delete $self->{fh};
		2285	my $wbuf = delete $self->{wbuf};
		2286
		2287	my @linger;
		2288
		2289	push @linger, AE::io $fh, 1, sub {
		2290	my $len = syswrite $fh, $wbuf, length $wbuf;
		2291
		2292	if ($len > 0) {
		2293	substr $wbuf, 0, $len, "";
		2294	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
		2295	@linger = (); # end
		2296	}
		2297	};
		2298	push @linger, AE::timer $linger, 0, sub {
		2299	@linger = ();
		2300	};
		2301	}
1002	}	2302	}
		2303
		2304	=item $handle->destroy
		2305
		2306	Shuts down the handle object as much as possible - this call ensures that
		2307	no further callbacks will be invoked and as many resources as possible
		2308	will be freed. Any method you will call on the handle object after
		2309	destroying it in this way will be silently ignored (and it will return the
		2310	empty list).
		2311
		2312	Normally, you can just "forget" any references to an AnyEvent::Handle
		2313	object and it will simply shut down. This works in fatal error and EOF
		2314	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2315	callback, so when you want to destroy the AnyEvent::Handle object from
		2316	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2317	that case.
		2318
		2319	Destroying the handle object in this way has the advantage that callbacks
		2320	will be removed as well, so if those are the only reference holders (as
		2321	is common), then one doesn't need to do anything special to break any
		2322	reference cycles.
		2323
		2324	The handle might still linger in the background and write out remaining
		2325	data, as specified by the C<linger> option, however.
		2326
		2327	=cut
		2328
		2329	sub destroy {
		2330	my ($self) = @_;
		2331
		2332	$self->DESTROY;
		2333	%$self = ();
		2334	bless $self, "AnyEvent::Handle::destroyed";
		2335	}
		2336
		2337	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2338	#nop
		2339	}
		2340
		2341	=item $handle->destroyed
		2342
		2343	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2344	->destroy >>, true otherwise.
		2345
		2346	Can be useful to decide whether the handle is still valid after some
		2347	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2348	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2349	can destroy the handle, so work can be avoided by checking sometimes:
		2350
		2351	$hdl->starttls ("accept");
		2352	return if $hdl->destroyed;
		2353	$hdl->push_write (...
		2354
		2355	Note that the call to C<push_write> will silently be ignored if the handle
		2356	has been destroyed, so often you can just ignore the possibility of the
		2357	handle being destroyed.
		2358
		2359	=cut
		2360
		2361	sub destroyed { 0 }
		2362	sub AnyEvent::Handle::destroyed::destroyed { 1 }
1003		2363
1004	=item AnyEvent::Handle::TLS_CTX	2364	=item AnyEvent::Handle::TLS_CTX
1005		2365
1006	This function creates and returns the Net::SSLeay::CTX object used by	2366	This function creates and returns the AnyEvent::TLS object used by default
1007	default for TLS mode.	2367	for TLS mode.
1008		2368
1009	The context is created like this:	2369	The context is created by calling L<AnyEvent::TLS> without any arguments.
1010
1011	Net::SSLeay::load_error_strings;
1012	Net::SSLeay::SSLeay_add_ssl_algorithms;
1013	Net::SSLeay::randomize;
1014
1015	my $CTX = Net::SSLeay::CTX_new;
1016
1017	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1018		2370
1019	=cut	2371	=cut
1020		2372
1021	our $TLS_CTX;	2373	our $TLS_CTX;
1022		2374
1023	sub TLS_CTX() {	2375	sub TLS_CTX() {
1024	$TLS_CTX || do {	2376	$TLS_CTX ||= do {
1025	require Net::SSLeay;	2377	require AnyEvent::TLS;
1026		2378
1027	Net::SSLeay::load_error_strings ();	2379	new AnyEvent::TLS
1028	Net::SSLeay::SSLeay_add_ssl_algorithms ();	2380	}
1029	Net::SSLeay::randomize ();	2381	}
1030		2382
1031	$TLS_CTX = Net::SSLeay::CTX_new ();	2383	=back
1032		2384
1033	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1034		2385
1035	$TLS_CTX	2386	=head1 NONFREQUENTLY ASKED QUESTIONS
		2387
		2388	=over 4
		2389
		2390	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2391	still get further invocations!
		2392
		2393	That's because AnyEvent::Handle keeps a reference to itself when handling
		2394	read or write callbacks.
		2395
		2396	It is only safe to "forget" the reference inside EOF or error callbacks,
		2397	from within all other callbacks, you need to explicitly call the C<<
		2398	->destroy >> method.
		2399
		2400	=item Why is my C<on_eof> callback never called?
		2401
		2402	Probably because your C<on_error> callback is being called instead: When
		2403	you have outstanding requests in your read queue, then an EOF is
		2404	considered an error as you clearly expected some data.
		2405
		2406	To avoid this, make sure you have an empty read queue whenever your handle
		2407	is supposed to be "idle" (i.e. connection closes are O.K.). You can set
		2408	an C<on_read> handler that simply pushes the first read requests in the
		2409	queue.
		2410
		2411	See also the next question, which explains this in a bit more detail.
		2412
		2413	=item How can I serve requests in a loop?
		2414
		2415	Most protocols consist of some setup phase (authentication for example)
		2416	followed by a request handling phase, where the server waits for requests
		2417	and handles them, in a loop.
		2418
		2419	There are two important variants: The first (traditional, better) variant
		2420	handles requests until the server gets some QUIT command, causing it to
		2421	close the connection first (highly desirable for a busy TCP server). A
		2422	client dropping the connection is an error, which means this variant can
		2423	detect an unexpected detection close.
		2424
		2425	To handle this case, always make sure you have a non-empty read queue, by
		2426	pushing the "read request start" handler on it:
		2427
		2428	# we assume a request starts with a single line
		2429	my @start_request; @start_request = (line => sub {
		2430	my ($hdl, $line) = @_;
		2431
		2432	... handle request
		2433
		2434	# push next request read, possibly from a nested callback
		2435	$hdl->push_read (@start_request);
		2436	});
		2437
		2438	# auth done, now go into request handling loop
		2439	# now push the first @start_request
		2440	$hdl->push_read (@start_request);
		2441
		2442	By always having an outstanding C<push_read>, the handle always expects
		2443	some data and raises the C<EPIPE> error when the connction is dropped
		2444	unexpectedly.
		2445
		2446	The second variant is a protocol where the client can drop the connection
		2447	at any time. For TCP, this means that the server machine may run out of
		2448	sockets easier, and in general, it means you cannot distinguish a protocl
		2449	failure/client crash from a normal connection close. Nevertheless, these
		2450	kinds of protocols are common (and sometimes even the best solution to the
		2451	problem).
		2452
		2453	Having an outstanding read request at all times is possible if you ignore
		2454	C<EPIPE> errors, but this doesn't help with when the client drops the
		2455	connection during a request, which would still be an error.
		2456
		2457	A better solution is to push the initial request read in an C<on_read>
		2458	callback. This avoids an error, as when the server doesn't expect data
		2459	(i.e. is idly waiting for the next request, an EOF will not raise an
		2460	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2461	and simpler:
		2462
		2463	# auth done, now go into request handling loop
		2464	$hdl->on_read (sub {
		2465	my ($hdl) = @_;
		2466
		2467	# called each time we receive data but the read queue is empty
		2468	# simply start read the request
		2469
		2470	$hdl->push_read (line => sub {
		2471	my ($hdl, $line) = @_;
		2472
		2473	... handle request
		2474
		2475	# do nothing special when the request has been handled, just
		2476	# let the request queue go empty.
		2477	});
		2478	});
		2479
		2480	=item I get different callback invocations in TLS mode/Why can't I pause
		2481	reading?
		2482
		2483	Unlike, say, TCP, TLS connections do not consist of two independent
		2484	communication channels, one for each direction. Or put differently, the
		2485	read and write directions are not independent of each other: you cannot
		2486	write data unless you are also prepared to read, and vice versa.
		2487
		2488	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2489	callback invocations when you are not expecting any read data - the reason
		2490	is that AnyEvent::Handle always reads in TLS mode.
		2491
		2492	During the connection, you have to make sure that you always have a
		2493	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2494	connection (or when you no longer want to use it) you can call the
		2495	C<destroy> method.
		2496
		2497	=item How do I read data until the other side closes the connection?
		2498
		2499	If you just want to read your data into a perl scalar, the easiest way
		2500	to achieve this is by setting an C<on_read> callback that does nothing,
		2501	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2502	will be in C<$_[0]{rbuf}>:
		2503
		2504	$handle->on_read (sub { });
		2505	$handle->on_eof (undef);
		2506	$handle->on_error (sub {
		2507	my $data = delete $_[0]{rbuf};
		2508	});
		2509
		2510	Note that this example removes the C<rbuf> member from the handle object,
		2511	which is not normally allowed by the API. It is expressly permitted in
		2512	this case only, as the handle object needs to be destroyed afterwards.
		2513
		2514	The reason to use C<on_error> is that TCP connections, due to latencies
		2515	and packets loss, might get closed quite violently with an error, when in
		2516	fact all data has been received.
		2517
		2518	It is usually better to use acknowledgements when transferring data,
		2519	to make sure the other side hasn't just died and you got the data
		2520	intact. This is also one reason why so many internet protocols have an
		2521	explicit QUIT command.
		2522
		2523	=item I don't want to destroy the handle too early - how do I wait until
		2524	all data has been written?
		2525
		2526	After writing your last bits of data, set the C<on_drain> callback
		2527	and destroy the handle in there - with the default setting of
		2528	C<low_water_mark> this will be called precisely when all data has been
		2529	written to the socket:
		2530
		2531	$handle->push_write (...);
		2532	$handle->on_drain (sub {
		2533	AE::log debug => "All data submitted to the kernel.";
		2534	undef $handle;
		2535	});
		2536
		2537	If you just want to queue some data and then signal EOF to the other side,
		2538	consider using C<< ->push_shutdown >> instead.
		2539
		2540	=item I want to contact a TLS/SSL server, I don't care about security.
		2541
		2542	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2543	connect to it and then create the AnyEvent::Handle with the C<tls>
		2544	parameter:
		2545
		2546	tcp_connect $host, $port, sub {
		2547	my ($fh) = @_;
		2548
		2549	my $handle = new AnyEvent::Handle
		2550	fh => $fh,
		2551	tls => "connect",
		2552	on_error => sub { ... };
		2553
		2554	$handle->push_write (...);
1036	}	2555	};
1037	}	2556
		2557	=item I want to contact a TLS/SSL server, I do care about security.
		2558
		2559	Then you should additionally enable certificate verification, including
		2560	peername verification, if the protocol you use supports it (see
		2561	L<AnyEvent::TLS>, C<verify_peername>).
		2562
		2563	E.g. for HTTPS:
		2564
		2565	tcp_connect $host, $port, sub {
		2566	my ($fh) = @_;
		2567
		2568	my $handle = new AnyEvent::Handle
		2569	fh => $fh,
		2570	peername => $host,
		2571	tls => "connect",
		2572	tls_ctx => { verify => 1, verify_peername => "https" },
		2573	...
		2574
		2575	Note that you must specify the hostname you connected to (or whatever
		2576	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2577	peername verification will be done.
		2578
		2579	The above will use the system-dependent default set of trusted CA
		2580	certificates. If you want to check against a specific CA, add the
		2581	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2582
		2583	tls_ctx => {
		2584	verify => 1,
		2585	verify_peername => "https",
		2586	ca_file => "my-ca-cert.pem",
		2587	},
		2588
		2589	=item I want to create a TLS/SSL server, how do I do that?
		2590
		2591	Well, you first need to get a server certificate and key. You have
		2592	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2593	self-signed certificate (cheap. check the search engine of your choice,
		2594	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2595	nice program for that purpose).
		2596
		2597	Then create a file with your private key (in PEM format, see
		2598	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2599	file should then look like this:
		2600
		2601	-----BEGIN RSA PRIVATE KEY-----
		2602	...header data
		2603	... lots of base64'y-stuff
		2604	-----END RSA PRIVATE KEY-----
		2605
		2606	-----BEGIN CERTIFICATE-----
		2607	... lots of base64'y-stuff
		2608	-----END CERTIFICATE-----
		2609
		2610	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2611	specify this file as C<cert_file>:
		2612
		2613	tcp_server undef, $port, sub {
		2614	my ($fh) = @_;
		2615
		2616	my $handle = new AnyEvent::Handle
		2617	fh => $fh,
		2618	tls => "accept",
		2619	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2620	...
		2621
		2622	When you have intermediate CA certificates that your clients might not
		2623	know about, just append them to the C<cert_file>.
1038		2624
1039	=back	2625	=back
1040		2626
1041	=head1 SUBCLASSING AnyEvent::Handle	2627	=head1 SUBCLASSING AnyEvent::Handle
1042		2628
…		…
1048	=over 4	2634	=over 4
1049		2635
1050	=item * all constructor arguments become object members.	2636	=item * all constructor arguments become object members.
1051		2637
1052	At least initially, when you pass a C<tls>-argument to the constructor it	2638	At least initially, when you pass a C<tls>-argument to the constructor it
1053	will end up in C<< $handle->{tls} >>. Those members might be changes or	2639	will end up in C<< $handle->{tls} >>. Those members might be changed or
1054	mutated later on (for example C<tls> will hold the TLS connection object).	2640	mutated later on (for example C<tls> will hold the TLS connection object).
1055		2641
1056	=item * other object member names are prefixed with an C<_>.	2642	=item * other object member names are prefixed with an C<_>.
1057		2643
1058	All object members not explicitly documented (internal use) are prefixed	2644	All object members not explicitly documented (internal use) are prefixed
…		…
1061		2647
1062	=item * all members not documented here and not prefixed with an underscore	2648	=item * all members not documented here and not prefixed with an underscore
1063	are free to use in subclasses.	2649	are free to use in subclasses.
1064		2650
1065	Of course, new versions of AnyEvent::Handle may introduce more "public"	2651	Of course, new versions of AnyEvent::Handle may introduce more "public"
1066	member variables, but thats just life, at least it is documented.	2652	member variables, but that's just life. At least it is documented.
1067		2653
1068	=back	2654	=back
1069		2655
1070	=head1 AUTHOR	2656	=head1 AUTHOR
1071		2657
1072	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	2658	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1073		2659
1074	=cut	2660	=cut
1075		2661
1076	1; # End of AnyEvent::Handle	2662	1
		2663

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