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Revision 1.229 by root, Mon Feb 27 17:14:02 2012 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict qw(subs vars);
5
6	use AnyEvent ();
7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();
9	use Carp ();
10	use Fcntl ();
11	use Errno qw(EAGAIN EINTR);
12
13	=head1 NAME	1	=head1 NAME
14		2
15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17	=cut
18
19	our $VERSION = 4.3;
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 => "got error $msg\n";
		17	$hdl->destroy;
		18	$cv->send;
34	);	19	};
35		20
36	# send some request line	21	# send some request line
37	$handle->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
38		23
39	# read the response line	24	# read the response line
40	$handle->push_read (line => sub {	25	$hdl->push_read (line => sub {
41	my ($handle, $line) = @_;	26	my ($hdl, $line) = @_;
42	warn "read line <$line>\n";	27	say "got line <$line>";
43	$cv->send;	28	$cv->send;
44	});	29	});
45		30
46	$cv->recv;	31	$cv->recv;
47		32
48	=head1 DESCRIPTION	33	=head1 DESCRIPTION
49		34
50	This module is a helper module to make it easier to do event-based I/O on	35	This is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	36	stream-based filehandles (sockets, pipes, and other stream things).
52	on sockets see L<AnyEvent::Util>.
53		37
54	The L<AnyEvent::Intro> tutorial contains some well-documented	38	The L<AnyEvent::Intro> tutorial contains some well-documented
55	AnyEvent::Handle examples.	39	AnyEvent::Handle examples.
56		40
57	In the following, when the documentation refers to of "bytes" then this	41	In the following, where the documentation refers to "bytes", it means
58	means characters. As sysread and syswrite are used for all I/O, their	42	characters. As sysread and syswrite are used for all I/O, their
59	treatment of characters applies to this module as well.	43	treatment of characters applies to this module as well.
		44
		45	At the very minimum, you should specify C<fh> or C<connect>, and the
		46	C<on_error> callback.
60		47
61	All callbacks will be invoked with the handle object as their first	48	All callbacks will be invoked with the handle object as their first
62	argument.	49	argument.
63		50
64	=head2 SIGPIPE is not handled by this module	51	=cut
65		52
66	SIGPIPE is not handled by this module, so one of the practical	53	package AnyEvent::Handle;
67	requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} =	54
68	'IGNORE'>). At least, this is highly recommend in a networked program: If	55	use Scalar::Util ();
69	you use AnyEvent::Handle in a filter program (like sort), exiting on	56	use List::Util ();
70	SIGPIPE is probably the right thing to do.	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 }
71		81
72	=head1 METHODS	82	=head1 METHODS
73		83
74	=over 4	84	=over 4
75		85
76	=item B<new (%args)>	86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
77		87
78	The constructor supports these arguments (all as key => value pairs).	88	The constructor supports these arguments (all as C<< key => value >> pairs).
79		89
80	=over 4	90	=over 4
81		91
82	=item fh => $filehandle [MANDATORY]	92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
83		93
84	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
85
86	NOTE: The filehandle will be set to non-blocking mode (using	95	NOTE: The filehandle will be set to non-blocking mode (using
87	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
88	that mode.	97	that mode.
89		98
		99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
		100
		101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
		104
		105	You have to specify either this parameter, or C<fh>, above.
		106
		107	It is possible to push requests on the read and write queues, and modify
		108	properties of the stream, even while AnyEvent::Handle is connecting.
		109
		110	When this parameter is specified, then the C<on_prepare>,
		111	C<on_connect_error> and C<on_connect> callbacks will be called under the
		112	appropriate circumstances:
		113
		114	=over 4
		115
90	=item on_eof => $cb->($handle)	116	=item on_prepare => $cb->($handle)
91		117
92	Set the callback to be called when an end-of-file condition is detected,	118	This (rarely used) callback is called before a new connection is
93	i.e. in the case of a socket, when the other side has closed the	119	attempted, but after the file handle has been created (you can access that
94	connection cleanly.	120	file handle via C<< $handle->{fh} >>). It could be used to prepare the
		121	file handle with parameters required for the actual connect (as opposed to
		122	settings that can be changed when the connection is already established).
95		123
96	For sockets, this just means that the other side has stopped sending data,	124	The return value of this callback should be the connect timeout value in
97	you can still try to write data, and, in fact, one can return from the eof	125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
98	callback and continue writing data, as only the read part has been shut	126	default timeout is to be used).
99	down.
100		127
101	While not mandatory, it is I<highly> recommended to set an eof callback,	128	=item on_connect => $cb->($handle, $host, $port, $retry->())
102	otherwise you might end up with a closed socket while you are still
103	waiting for data.
104		129
105	If an EOF condition has been detected but no C<on_eof> callback has been	130	This callback is called when a connection has been successfully established.
106	set, then a fatal error will be raised with C<$!> set to <0>.
107		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
108	=item on_error => $cb->($handle, $fatal)	160	=item on_error => $cb->($handle, $fatal, $message)
109		161
110	This is the error callback, which is called when, well, some error	162	This is the error callback, which is called when, well, some error
111	occured, such as not being able to resolve the hostname, failure to	163	occured, such as not being able to resolve the hostname, failure to
112	connect or a read error.	164	connect, or a read error.
113		165
114	Some errors are fatal (which is indicated by C<$fatal> being true). On	166	Some errors are fatal (which is indicated by C<$fatal> being true). On
115	fatal errors the handle object will be shut down and will not be usable	167	fatal errors the handle object will be destroyed (by a call to C<< ->
116	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal	168	destroy >>) after invoking the error callback (which means you are free to
117	errors are an EOF condition with active (but unsatisifable) read watchers	169	examine the handle object). Examples of fatal errors are an EOF condition
118	(C<EPIPE>) or I/O errors.	170	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		171	cases where the other side can close the connection at will, it is
		172	often easiest to not report C<EPIPE> errors in this callback.
119		173
		174	AnyEvent::Handle tries to find an appropriate error code for you to check
		175	against, but in some cases (TLS errors), this does not work well. It is
		176	recommended to always output the C<$message> argument in human-readable
		177	error messages (it's usually the same as C<"$!">).
		178
120	Non-fatal errors can be retried by simply returning, but it is recommended	179	Non-fatal errors can be retried by returning, but it is recommended
121	to simply ignore this parameter and instead abondon the handle object	180	to simply ignore this parameter and instead abondon the handle object
122	when this callback is invoked. Examples of non-fatal errors are timeouts	181	when this callback is invoked. Examples of non-fatal errors are timeouts
123	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).	182	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
124		183
125	On callback entrance, the value of C<$!> contains the operating system	184	On entry to the callback, the value of C<$!> contains the operating
126	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).	185	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		186	C<EPROTO>).
127		187
128	While not mandatory, it is I<highly> recommended to set this callback, as	188	While not mandatory, it is I<highly> recommended to set this callback, as
129	you will not be notified of errors otherwise. The default simply calls	189	you will not be notified of errors otherwise. The default just calls
130	C<croak>.	190	C<croak>.
131		191
132	=item on_read => $cb->($handle)	192	=item on_read => $cb->($handle)
133		193
134	This sets the default read callback, which is called when data arrives	194	This sets the default read callback, which is called when data arrives
135	and no read request is in the queue (unlike read queue callbacks, this	195	and no read request is in the queue (unlike read queue callbacks, this
136	callback will only be called when at least one octet of data is in the	196	callback will only be called when at least one octet of data is in the
137	read buffer).	197	read buffer).
138		198
139	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	199	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
140	method or access the C<$handle->{rbuf}> member directly.	200	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		201	must not enlarge or modify the read buffer, you can only remove data at
		202	the beginning from it.
141		203
		204	You can also call C<< ->push_read (...) >> or any other function that
		205	modifies the read queue. Or do both. Or ...
		206
142	When an EOF condition is detected then AnyEvent::Handle will first try to	207	When an EOF condition is detected, AnyEvent::Handle will first try to
143	feed all the remaining data to the queued callbacks and C<on_read> before	208	feed all the remaining data to the queued callbacks and C<on_read> before
144	calling the C<on_eof> callback. If no progress can be made, then a fatal	209	calling the C<on_eof> callback. If no progress can be made, then a fatal
145	error will be raised (with C<$!> set to C<EPIPE>).	210	error will be raised (with C<$!> set to C<EPIPE>).
146		211
		212	Note that, unlike requests in the read queue, an C<on_read> callback
		213	doesn't mean you I<require> some data: if there is an EOF and there
		214	are outstanding read requests then an error will be flagged. With an
		215	C<on_read> callback, the C<on_eof> callback will be invoked.
		216
		217	=item on_eof => $cb->($handle)
		218
		219	Set the callback to be called when an end-of-file condition is detected,
		220	i.e. in the case of a socket, when the other side has closed the
		221	connection cleanly, and there are no outstanding read requests in the
		222	queue (if there are read requests, then an EOF counts as an unexpected
		223	connection close and will be flagged as an error).
		224
		225	For sockets, this just means that the other side has stopped sending data,
		226	you can still try to write data, and, in fact, one can return from the EOF
		227	callback and continue writing data, as only the read part has been shut
		228	down.
		229
		230	If an EOF condition has been detected but no C<on_eof> callback has been
		231	set, then a fatal error will be raised with C<$!> set to <0>.
		232
147	=item on_drain => $cb->($handle)	233	=item on_drain => $cb->($handle)
148		234
149	This sets the callback that is called when the write buffer becomes empty	235	This sets the callback that is called once when the write buffer becomes
150	(or when the callback is set and the buffer is empty already).	236	empty (and immediately when the handle object is created).
151		237
152	To append to the write buffer, use the C<< ->push_write >> method.	238	To append to the write buffer, use the C<< ->push_write >> method.
153		239
154	This callback is useful when you don't want to put all of your write data	240	This callback is useful when you don't want to put all of your write data
155	into the queue at once, for example, when you want to write the contents	241	into the queue at once, for example, when you want to write the contents
…		…
157	memory and push it into the queue, but instead only read more data from	243	memory and push it into the queue, but instead only read more data from
158	the file when the write queue becomes empty.	244	the file when the write queue becomes empty.
159		245
160	=item timeout => $fractional_seconds	246	=item timeout => $fractional_seconds
161		247
		248	=item rtimeout => $fractional_seconds
		249
		250	=item wtimeout => $fractional_seconds
		251
162	If non-zero, then this enables an "inactivity" timeout: whenever this many	252	If non-zero, then these enables an "inactivity" timeout: whenever this
163	seconds pass without a successful read or write on the underlying file	253	many seconds pass without a successful read or write on the underlying
164	handle, the C<on_timeout> callback will be invoked (and if that one is	254	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
165	missing, a non-fatal C<ETIMEDOUT> error will be raised).	255	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		256	error will be raised).
166		257
		258	There are three variants of the timeouts that work independently of each
		259	other, for both read and write (triggered when nothing was read I<OR>
		260	written), just read (triggered when nothing was read), and just write:
		261	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		262	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		263	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		264
167	Note that timeout processing is also active when you currently do not have	265	Note that timeout processing is active even when you do not have any
168	any outstanding read or write requests: If you plan to keep the connection	266	outstanding read or write requests: If you plan to keep the connection
169	idle then you should disable the timout temporarily or ignore the timeout	267	idle then you should disable the timeout temporarily or ignore the
170	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply	268	timeout in the corresponding C<on_timeout> callback, in which case
171	restart the timeout.	269	AnyEvent::Handle will simply restart the timeout.
172		270
173	Zero (the default) disables this timeout.	271	Zero (the default) disables the corresponding timeout.
174		272
175	=item on_timeout => $cb->($handle)	273	=item on_timeout => $cb->($handle)
		274
		275	=item on_rtimeout => $cb->($handle)
		276
		277	=item on_wtimeout => $cb->($handle)
176		278
177	Called whenever the inactivity timeout passes. If you return from this	279	Called whenever the inactivity timeout passes. If you return from this
178	callback, then the timeout will be reset as if some activity had happened,	280	callback, then the timeout will be reset as if some activity had happened,
179	so this condition is not fatal in any way.	281	so this condition is not fatal in any way.
180		282
…		…
188	be configured to accept only so-and-so much data that it cannot act on	290	be configured to accept only so-and-so much data that it cannot act on
189	(for example, when expecting a line, an attacker could send an unlimited	291	(for example, when expecting a line, an attacker could send an unlimited
190	amount of data without a callback ever being called as long as the line	292	amount of data without a callback ever being called as long as the line
191	isn't finished).	293	isn't finished).
192		294
		295	=item wbuf_max => <bytes>
		296
		297	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		298	when the write buffer ever (strictly) exceeds this size. This is useful to
		299	avoid some forms of denial-of-service attacks.
		300
		301	Although the units of this parameter is bytes, this is the I<raw> number
		302	of bytes not yet accepted by the kernel. This can make a difference when
		303	you e.g. use TLS, as TLS typically makes your write data larger (but it
		304	can also make it smaller due to compression).
		305
		306	As an example of when this limit is useful, take a chat server that sends
		307	chat messages to a client. If the client does not read those in a timely
		308	manner then the send buffer in the server would grow unbounded.
		309
193	=item autocork => <boolean>	310	=item autocork => <boolean>
194		311
195	When disabled (the default), then C<push_write> will try to immediately	312	When disabled (the default), C<push_write> will try to immediately
196	write the data to the handle, if possible. This avoids having to register	313	write the data to the handle if possible. This avoids having to register
197	a write watcher and wait for the next event loop iteration, but can	314	a write watcher and wait for the next event loop iteration, but can
198	be inefficient if you write multiple small chunks (on the wire, this	315	be inefficient if you write multiple small chunks (on the wire, this
199	disadvantage is usually avoided by your kernel's nagle algorithm, see	316	disadvantage is usually avoided by your kernel's nagle algorithm, see
200	C<no_delay>, but this option can save costly syscalls).	317	C<no_delay>, but this option can save costly syscalls).
201		318
202	When enabled, then writes will always be queued till the next event loop	319	When enabled, writes will always be queued till the next event loop
203	iteration. This is efficient when you do many small writes per iteration,	320	iteration. This is efficient when you do many small writes per iteration,
204	but less efficient when you do a single write only per iteration (or when	321	but less efficient when you do a single write only per iteration (or when
205	the write buffer often is full). It also increases write latency.	322	the write buffer often is full). It also increases write latency.
206		323
207	=item no_delay => <boolean>	324	=item no_delay => <boolean>
…		…
211	the Nagle algorithm, and usually it is beneficial.	328	the Nagle algorithm, and usually it is beneficial.
212		329
213	In some situations you want as low a delay as possible, which can be	330	In some situations you want as low a delay as possible, which can be
214	accomplishd by setting this option to a true value.	331	accomplishd by setting this option to a true value.
215		332
216	The default is your opertaing system's default behaviour (most likely	333	The default is your operating system's default behaviour (most likely
217	enabled), this option explicitly enables or disables it, if possible.	334	enabled). This option explicitly enables or disables it, if possible.
		335
		336	=item keepalive => <boolean>
		337
		338	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		339	normally, TCP connections have no time-out once established, so TCP
		340	connections, once established, can stay alive forever even when the other
		341	side has long gone. TCP keepalives are a cheap way to take down long-lived
		342	TCP connections when the other side becomes unreachable. While the default
		343	is OS-dependent, TCP keepalives usually kick in after around two hours,
		344	and, if the other side doesn't reply, take down the TCP connection some 10
		345	to 15 minutes later.
		346
		347	It is harmless to specify this option for file handles that do not support
		348	keepalives, and enabling it on connections that are potentially long-lived
		349	is usually a good idea.
		350
		351	=item oobinline => <boolean>
		352
		353	BSD majorly fucked up the implementation of TCP urgent data. The result
		354	is that almost no OS implements TCP according to the specs, and every OS
		355	implements it slightly differently.
		356
		357	If you want to handle TCP urgent data, then setting this flag (the default
		358	is enabled) gives you the most portable way of getting urgent data, by
		359	putting it into the stream.
		360
		361	Since BSD emulation of OOB data on top of TCP's urgent data can have
		362	security implications, AnyEvent::Handle sets this flag automatically
		363	unless explicitly specified. Note that setting this flag after
		364	establishing a connection I<may> be a bit too late (data loss could
		365	already have occured on BSD systems), but at least it will protect you
		366	from most attacks.
218		367
219	=item read_size => <bytes>	368	=item read_size => <bytes>
220		369
221	The default read block size (the amount of bytes this module will	370	The initial read block size, the number of bytes this module will try
222	try to read during each loop iteration, which affects memory	371	to read during each loop iteration. Each handle object will consume
223	requirements). Default: C<8192>.	372	at least this amount of memory for the read buffer as well, so when
		373	handling many connections watch out for memory requirements). See also
		374	C<max_read_size>. Default: C<2048>.
		375
		376	=item max_read_size => <bytes>
		377
		378	The maximum read buffer size used by the dynamic adjustment
		379	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		380	one go it will double C<read_size> up to the maximum given by this
		381	option. Default: C<131072> or C<read_size>, whichever is higher.
224		382
225	=item low_water_mark => <bytes>	383	=item low_water_mark => <bytes>
226		384
227	Sets the amount of bytes (default: C<0>) that make up an "empty" write	385	Sets the number of bytes (default: C<0>) that make up an "empty" write
228	buffer: If the write reaches this size or gets even samller it is	386	buffer: If the buffer reaches this size or gets even samller it is
229	considered empty.	387	considered empty.
230		388
231	Sometimes it can be beneficial (for performance reasons) to add data to	389	Sometimes it can be beneficial (for performance reasons) to add data to
232	the write buffer before it is fully drained, but this is a rare case, as	390	the write buffer before it is fully drained, but this is a rare case, as
233	the operating system kernel usually buffers data as well, so the default	391	the operating system kernel usually buffers data as well, so the default
234	is good in almost all cases.	392	is good in almost all cases.
235		393
236	=item linger => <seconds>	394	=item linger => <seconds>
237		395
238	If non-zero (default: C<3600>), then the destructor of the	396	If this is non-zero (default: C<3600>), the destructor of the
239	AnyEvent::Handle object will check whether there is still outstanding	397	AnyEvent::Handle object will check whether there is still outstanding
240	write data and will install a watcher that will write this data to the	398	write data and will install a watcher that will write this data to the
241	socket. No errors will be reported (this mostly matches how the operating	399	socket. No errors will be reported (this mostly matches how the operating
242	system treats outstanding data at socket close time).	400	system treats outstanding data at socket close time).
243		401
244	This will not work for partial TLS data that could not be encoded	402	This will not work for partial TLS data that could not be encoded
245	yet. This data will be lost. Calling the C<stoptls> method in time might	403	yet. This data will be lost. Calling the C<stoptls> method in time might
246	help.	404	help.
247		405
		406	=item peername => $string
		407
		408	A string used to identify the remote site - usually the DNS hostname
		409	(I<not> IDN!) used to create the connection, rarely the IP address.
		410
		411	Apart from being useful in error messages, this string is also used in TLS
		412	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		413	verification will be skipped when C<peername> is not specified or is
		414	C<undef>.
		415
248	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	416	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
249		417
250	When this parameter is given, it enables TLS (SSL) mode, that means	418	When this parameter is given, it enables TLS (SSL) mode, that means
251	AnyEvent will start a TLS handshake as soon as the conenction has been	419	AnyEvent will start a TLS handshake as soon as the connection has been
252	established and will transparently encrypt/decrypt data afterwards.	420	established and will transparently encrypt/decrypt data afterwards.
		421
		422	All TLS protocol errors will be signalled as C<EPROTO>, with an
		423	appropriate error message.
253		424
254	TLS mode requires Net::SSLeay to be installed (it will be loaded	425	TLS mode requires Net::SSLeay to be installed (it will be loaded
255	automatically when you try to create a TLS handle): this module doesn't	426	automatically when you try to create a TLS handle): this module doesn't
256	have a dependency on that module, so if your module requires it, you have	427	have a dependency on that module, so if your module requires it, you have
257	to add the dependency yourself.	428	to add the dependency yourself.
…		…
261	mode.	432	mode.
262		433
263	You can also provide your own TLS connection object, but you have	434	You can also provide your own TLS connection object, but you have
264	to make sure that you call either C<Net::SSLeay::set_connect_state>	435	to make sure that you call either C<Net::SSLeay::set_connect_state>
265	or C<Net::SSLeay::set_accept_state> on it before you pass it to	436	or C<Net::SSLeay::set_accept_state> on it before you pass it to
266	AnyEvent::Handle.	437	AnyEvent::Handle. Also, this module will take ownership of this connection
		438	object.
267		439
		440	At some future point, AnyEvent::Handle might switch to another TLS
		441	implementation, then the option to use your own session object will go
		442	away.
		443
		444	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		445	passing in the wrong integer will lead to certain crash. This most often
		446	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		447	segmentation fault.
		448
268	See the C<< ->starttls >> method for when need to start TLS negotiation later.	449	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
269		450
270	=item tls_ctx => $ssl_ctx	451	=item tls_ctx => $anyevent_tls
271		452
272	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection	453	Use the given C<AnyEvent::TLS> object to create the new TLS connection
273	(unless a connection object was specified directly). If this parameter is	454	(unless a connection object was specified directly). If this
274	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	455	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		456	C<AnyEvent::Handle::TLS_CTX>.
		457
		458	Instead of an object, you can also specify a hash reference with C<< key
		459	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		460	new TLS context object.
		461
		462	=item on_starttls => $cb->($handle, $success[, $error_message])
		463
		464	This callback will be invoked when the TLS/SSL handshake has finished. If
		465	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		466	(C<on_stoptls> will not be called in this case).
		467
		468	The session in C<< $handle->{tls} >> can still be examined in this
		469	callback, even when the handshake was not successful.
		470
		471	TLS handshake failures will not cause C<on_error> to be invoked when this
		472	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		473
		474	Without this callback, handshake failures lead to C<on_error> being
		475	called as usual.
		476
		477	Note that you cannot just call C<starttls> again in this callback. If you
		478	need to do that, start an zero-second timer instead whose callback can
		479	then call C<< ->starttls >> again.
		480
		481	=item on_stoptls => $cb->($handle)
		482
		483	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		484	set, then it will be invoked after freeing the TLS session. If it is not,
		485	then a TLS shutdown condition will be treated like a normal EOF condition
		486	on the handle.
		487
		488	The session in C<< $handle->{tls} >> can still be examined in this
		489	callback.
		490
		491	This callback will only be called on TLS shutdowns, not when the
		492	underlying handle signals EOF.
275		493
276	=item json => JSON or JSON::XS object	494	=item json => JSON or JSON::XS object
277		495
278	This is the json coder object used by the C<json> read and write types.	496	This is the json coder object used by the C<json> read and write types.
279		497
…		…
288		506
289	=cut	507	=cut
290		508
291	sub new {	509	sub new {
292	my $class = shift;	510	my $class = shift;
293
294	my $self = bless { @_ }, $class;	511	my $self = bless { @_ }, $class;
295		512
296	$self->{fh} or Carp::croak "mandatory argument fh is missing";	513	if ($self->{fh}) {
		514	$self->_start;
		515	return unless $self->{fh}; # could be gone by now
		516
		517	} elsif ($self->{connect}) {
		518	require AnyEvent::Socket;
		519
		520	$self->{peername} = $self->{connect}[0]
		521	unless exists $self->{peername};
		522
		523	$self->{_skip_drain_rbuf} = 1;
		524
		525	{
		526	Scalar::Util::weaken (my $self = $self);
		527
		528	$self->{_connect} =
		529	AnyEvent::Socket::tcp_connect (
		530	$self->{connect}[0],
		531	$self->{connect}[1],
		532	sub {
		533	my ($fh, $host, $port, $retry) = @_;
		534
		535	delete $self->{_connect}; # no longer needed
		536
		537	if ($fh) {
		538	$self->{fh} = $fh;
		539
		540	delete $self->{_skip_drain_rbuf};
		541	$self->_start;
		542
		543	$self->{on_connect}
		544	and $self->{on_connect}($self, $host, $port, sub {
		545	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		546	$self->{_skip_drain_rbuf} = 1;
		547	&$retry;
		548	});
		549
		550	} else {
		551	if ($self->{on_connect_error}) {
		552	$self->{on_connect_error}($self, "$!");
		553	$self->destroy if $self;
		554	} else {
		555	$self->_error ($!, 1);
		556	}
		557	}
		558	},
		559	sub {
		560	local $self->{fh} = $_[0];
		561
		562	$self->{on_prepare}
		563	? $self->{on_prepare}->($self)
		564	: ()
		565	}
		566	);
		567	}
		568
		569	} else {
		570	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		571	}
		572
		573	$self
		574	}
		575
		576	sub _start {
		577	my ($self) = @_;
		578
		579	# too many clueless people try to use udp and similar sockets
		580	# with AnyEvent::Handle, do them a favour.
		581	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		582	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		583	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
297		584
298	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	585	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
299		586
		587	$self->{_activity} =
		588	$self->{_ractivity} =
		589	$self->{_wactivity} = AE::now;
		590
		591	$self->{read_size} ||= 2048;
		592	$self->{max_read_size} = $self->{read_size}
		593	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		594
		595	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		596	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		597	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		598
		599	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		600	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		601
		602	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		603
300	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})	604	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
301	if $self->{tls};	605	if $self->{tls};
302		606
303	$self->{_activity} = AnyEvent->now;
304	$self->_timeout;
305
306	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};	607	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
307	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
308		608
309	$self->start_read	609	$self->start_read
310	if $self->{on_read};	610	if $self->{on_read} || @{ $self->{_queue} };
311		611
312	$self	612	$self->_drain_wbuf;
313	}
314
315	sub _shutdown {
316	my ($self) = @_;
317
318	delete $self->{_tw};
319	delete $self->{_rw};
320	delete $self->{_ww};
321	delete $self->{fh};
322
323	&_freetls;
324
325	delete $self->{on_read};
326	delete $self->{_queue};
327	}	613	}
328		614
329	sub _error {	615	sub _error {
330	my ($self, $errno, $fatal) = @_;	616	my ($self, $errno, $fatal, $message) = @_;
331
332	$self->_shutdown
333	if $fatal;
334		617
335	$! = $errno;	618	$! = $errno;
		619	$message ||= "$!";
336		620
337	if ($self->{on_error}) {	621	if ($self->{on_error}) {
338	$self->{on_error}($self, $fatal);	622	$self->{on_error}($self, $fatal, $message);
339	} else {	623	$self->destroy if $fatal;
		624	} elsif ($self->{fh} || $self->{connect}) {
		625	$self->destroy;
340	Carp::croak "AnyEvent::Handle uncaught error: $!";	626	Carp::croak "AnyEvent::Handle uncaught error: $message";
341	}	627	}
342	}	628	}
343		629
344	=item $fh = $handle->fh	630	=item $fh = $handle->fh
345		631
…		…
369	$_[0]{on_eof} = $_[1];	655	$_[0]{on_eof} = $_[1];
370	}	656	}
371		657
372	=item $handle->on_timeout ($cb)	658	=item $handle->on_timeout ($cb)
373		659
374	Replace the current C<on_timeout> callback, or disables the callback (but	660	=item $handle->on_rtimeout ($cb)
375	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
376	argument and method.
377		661
378	=cut	662	=item $handle->on_wtimeout ($cb)
379		663
380	sub on_timeout {	664	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
381	$_[0]{on_timeout} = $_[1];	665	callback, or disables the callback (but not the timeout) if C<$cb> =
382	}	666	C<undef>. See the C<timeout> constructor argument and method.
		667
		668	=cut
		669
		670	# see below
383		671
384	=item $handle->autocork ($boolean)	672	=item $handle->autocork ($boolean)
385		673
386	Enables or disables the current autocork behaviour (see C<autocork>	674	Enables or disables the current autocork behaviour (see C<autocork>
387	constructor argument).	675	constructor argument). Changes will only take effect on the next write.
388		676
389	=cut	677	=cut
		678
		679	sub autocork {
		680	$_[0]{autocork} = $_[1];
		681	}
390		682
391	=item $handle->no_delay ($boolean)	683	=item $handle->no_delay ($boolean)
392		684
393	Enables or disables the C<no_delay> setting (see constructor argument of	685	Enables or disables the C<no_delay> setting (see constructor argument of
394	the same name for details).	686	the same name for details).
…		…
396	=cut	688	=cut
397		689
398	sub no_delay {	690	sub no_delay {
399	$_[0]{no_delay} = $_[1];	691	$_[0]{no_delay} = $_[1];
400		692
		693	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		694	if $_[0]{fh};
		695	}
		696
		697	=item $handle->keepalive ($boolean)
		698
		699	Enables or disables the C<keepalive> setting (see constructor argument of
		700	the same name for details).
		701
		702	=cut
		703
		704	sub keepalive {
		705	$_[0]{keepalive} = $_[1];
		706
401	eval {	707	eval {
402	local $SIG{__DIE__};	708	local $SIG{__DIE__};
403	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];	709	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		710	if $_[0]{fh};
404	};	711	};
405	}	712	}
406		713
		714	=item $handle->oobinline ($boolean)
		715
		716	Enables or disables the C<oobinline> setting (see constructor argument of
		717	the same name for details).
		718
		719	=cut
		720
		721	sub oobinline {
		722	$_[0]{oobinline} = $_[1];
		723
		724	eval {
		725	local $SIG{__DIE__};
		726	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		727	if $_[0]{fh};
		728	};
		729	}
		730
		731	=item $handle->keepalive ($boolean)
		732
		733	Enables or disables the C<keepalive> setting (see constructor argument of
		734	the same name for details).
		735
		736	=cut
		737
		738	sub keepalive {
		739	$_[0]{keepalive} = $_[1];
		740
		741	eval {
		742	local $SIG{__DIE__};
		743	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		744	if $_[0]{fh};
		745	};
		746	}
		747
		748	=item $handle->on_starttls ($cb)
		749
		750	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		751
		752	=cut
		753
		754	sub on_starttls {
		755	$_[0]{on_starttls} = $_[1];
		756	}
		757
		758	=item $handle->on_stoptls ($cb)
		759
		760	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		761
		762	=cut
		763
		764	sub on_stoptls {
		765	$_[0]{on_stoptls} = $_[1];
		766	}
		767
		768	=item $handle->rbuf_max ($max_octets)
		769
		770	Configures the C<rbuf_max> setting (C<undef> disables it).
		771
		772	=item $handle->wbuf_max ($max_octets)
		773
		774	Configures the C<wbuf_max> setting (C<undef> disables it).
		775
		776	=cut
		777
		778	sub rbuf_max {
		779	$_[0]{rbuf_max} = $_[1];
		780	}
		781
		782	sub wbuf_max {
		783	$_[0]{wbuf_max} = $_[1];
		784	}
		785
407	#############################################################################	786	#############################################################################
408		787
409	=item $handle->timeout ($seconds)	788	=item $handle->timeout ($seconds)
410		789
		790	=item $handle->rtimeout ($seconds)
		791
		792	=item $handle->wtimeout ($seconds)
		793
411	Configures (or disables) the inactivity timeout.	794	Configures (or disables) the inactivity timeout.
412		795
413	=cut	796	The timeout will be checked instantly, so this method might destroy the
		797	handle before it returns.
414		798
415	sub timeout {	799	=item $handle->timeout_reset
		800
		801	=item $handle->rtimeout_reset
		802
		803	=item $handle->wtimeout_reset
		804
		805	Reset the activity timeout, as if data was received or sent.
		806
		807	These methods are cheap to call.
		808
		809	=cut
		810
		811	for my $dir ("", "r", "w") {
		812	my $timeout = "${dir}timeout";
		813	my $tw = "_${dir}tw";
		814	my $on_timeout = "on_${dir}timeout";
		815	my $activity = "_${dir}activity";
		816	my $cb;
		817
		818	*$on_timeout = sub {
		819	$_[0]{$on_timeout} = $_[1];
		820	};
		821
		822	*$timeout = sub {
416	my ($self, $timeout) = @_;	823	my ($self, $new_value) = @_;
417		824
		825	$new_value >= 0
		826	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		827
418	$self->{timeout} = $timeout;	828	$self->{$timeout} = $new_value;
419	$self->_timeout;	829	delete $self->{$tw}; &$cb;
420	}	830	};
421		831
		832	*{"${dir}timeout_reset"} = sub {
		833	$_[0]{$activity} = AE::now;
		834	};
		835
		836	# main workhorse:
422	# reset the timeout watcher, as neccessary	837	# reset the timeout watcher, as neccessary
423	# also check for time-outs	838	# also check for time-outs
424	sub _timeout {	839	$cb = sub {
425	my ($self) = @_;	840	my ($self) = @_;
426		841
427	if ($self->{timeout}) {	842	if ($self->{$timeout} && $self->{fh}) {
428	my $NOW = AnyEvent->now;	843	my $NOW = AE::now;
429		844
430	# when would the timeout trigger?	845	# when would the timeout trigger?
431	my $after = $self->{_activity} + $self->{timeout} - $NOW;	846	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
432		847
433	# now or in the past already?	848	# now or in the past already?
434	if ($after <= 0) {	849	if ($after <= 0) {
435	$self->{_activity} = $NOW;	850	$self->{$activity} = $NOW;
436		851
437	if ($self->{on_timeout}) {	852	if ($self->{$on_timeout}) {
438	$self->{on_timeout}($self);	853	$self->{$on_timeout}($self);
439	} else {	854	} else {
440	$self->_error (&Errno::ETIMEDOUT);	855	$self->_error (Errno::ETIMEDOUT);
		856	}
		857
		858	# callback could have changed timeout value, optimise
		859	return unless $self->{$timeout};
		860
		861	# calculate new after
		862	$after = $self->{$timeout};
441	}	863	}
442		864
443	# callback could have changed timeout value, optimise	865	Scalar::Util::weaken $self;
444	return unless $self->{timeout};	866	return unless $self; # ->error could have destroyed $self
445		867
446	# calculate new after	868	$self->{$tw} ||= AE::timer $after, 0, sub {
447	$after = $self->{timeout};	869	delete $self->{$tw};
		870	$cb->($self);
		871	};
		872	} else {
		873	delete $self->{$tw};
448	}	874	}
449
450	Scalar::Util::weaken $self;
451	return unless $self; # ->error could have destroyed $self
452
453	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
454	delete $self->{_tw};
455	$self->_timeout;
456	});
457	} else {
458	delete $self->{_tw};
459	}	875	}
460	}	876	}
461		877
462	#############################################################################	878	#############################################################################
463		879
…		…
470		886
471	The write queue is very simple: you can add data to its end, and	887	The write queue is very simple: you can add data to its end, and
472	AnyEvent::Handle will automatically try to get rid of it for you.	888	AnyEvent::Handle will automatically try to get rid of it for you.
473		889
474	When data could be written and the write buffer is shorter then the low	890	When data could be written and the write buffer is shorter then the low
475	water mark, the C<on_drain> callback will be invoked.	891	water mark, the C<on_drain> callback will be invoked once.
476		892
477	=over 4	893	=over 4
478		894
479	=item $handle->on_drain ($cb)	895	=item $handle->on_drain ($cb)
480		896
481	Sets the C<on_drain> callback or clears it (see the description of	897	Sets the C<on_drain> callback or clears it (see the description of
482	C<on_drain> in the constructor).	898	C<on_drain> in the constructor).
483		899
		900	This method may invoke callbacks (and therefore the handle might be
		901	destroyed after it returns).
		902
484	=cut	903	=cut
485		904
486	sub on_drain {	905	sub on_drain {
487	my ($self, $cb) = @_;	906	my ($self, $cb) = @_;
488		907
…		…
492	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});	911	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
493	}	912	}
494		913
495	=item $handle->push_write ($data)	914	=item $handle->push_write ($data)
496		915
497	Queues the given scalar to be written. You can push as much data as you	916	Queues the given scalar to be written. You can push as much data as
498	want (only limited by the available memory), as C<AnyEvent::Handle>	917	you want (only limited by the available memory and C<wbuf_max>), as
499	buffers it independently of the kernel.	918	C<AnyEvent::Handle> buffers it independently of the kernel.
		919
		920	This method may invoke callbacks (and therefore the handle might be
		921	destroyed after it returns).
500		922
501	=cut	923	=cut
502		924
503	sub _drain_wbuf {	925	sub _drain_wbuf {
504	my ($self) = @_;	926	my ($self) = @_;
…		…
508	Scalar::Util::weaken $self;	930	Scalar::Util::weaken $self;
509		931
510	my $cb = sub {	932	my $cb = sub {
511	my $len = syswrite $self->{fh}, $self->{wbuf};	933	my $len = syswrite $self->{fh}, $self->{wbuf};
512		934
513	if ($len >= 0) {	935	if (defined $len) {
514	substr $self->{wbuf}, 0, $len, "";	936	substr $self->{wbuf}, 0, $len, "";
515		937
516	$self->{_activity} = AnyEvent->now;	938	$self->{_activity} = $self->{_wactivity} = AE::now;
517		939
518	$self->{on_drain}($self)	940	$self->{on_drain}($self)
519	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})	941	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
520	&& $self->{on_drain};	942	&& $self->{on_drain};
521		943
…		…
527		949
528	# try to write data immediately	950	# try to write data immediately
529	$cb->() unless $self->{autocork};	951	$cb->() unless $self->{autocork};
530		952
531	# if still data left in wbuf, we need to poll	953	# if still data left in wbuf, we need to poll
532	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	954	$self->{_ww} = AE::io $self->{fh}, 1, $cb
533	if length $self->{wbuf};	955	if length $self->{wbuf};
		956
		957	if (
		958	defined $self->{wbuf_max}
		959	&& $self->{wbuf_max} < length $self->{wbuf}
		960	) {
		961	$self->_error (Errno::ENOSPC, 1), return;
		962	}
534	};	963	};
535	}	964	}
536		965
537	our %WH;	966	our %WH;
538		967
		968	# deprecated
539	sub register_write_type($$) {	969	sub register_write_type($$) {
540	$WH{$_[0]} = $_[1];	970	$WH{$_[0]} = $_[1];
541	}	971	}
542		972
543	sub push_write {	973	sub push_write {
544	my $self = shift;	974	my $self = shift;
545		975
546	if (@_ > 1) {	976	if (@_ > 1) {
547	my $type = shift;	977	my $type = shift;
548		978
		979	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
549	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	980	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
550	->($self, @_);	981	->($self, @_);
551	}	982	}
552		983
		984	# we downgrade here to avoid hard-to-track-down bugs,
		985	# and diagnose the problem earlier and better.
		986
553	if ($self->{tls}) {	987	if ($self->{tls}) {
554	$self->{_tls_wbuf} .= $_[0];	988	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
555	&_dotls ($self);	989	&_dotls ($self) if $self->{fh};
556	} else {	990	} else {
557	$self->{wbuf} .= $_[0];	991	utf8::downgrade $self->{wbuf} .= $_[0];
558	$self->_drain_wbuf;	992	$self->_drain_wbuf if $self->{fh};
559	}	993	}
560	}	994	}
561		995
562	=item $handle->push_write (type => @args)	996	=item $handle->push_write (type => @args)
563		997
564	Instead of formatting your data yourself, you can also let this module do	998	Instead of formatting your data yourself, you can also let this module
565	the job by specifying a type and type-specific arguments.	999	do the job by specifying a type and type-specific arguments. You
		1000	can also specify the (fully qualified) name of a package, in which
		1001	case AnyEvent tries to load the package and then expects to find the
		1002	C<anyevent_write_type> function inside (see "custom write types", below).
566		1003
567	Predefined types are (if you have ideas for additional types, feel free to	1004	Predefined types are (if you have ideas for additional types, feel free to
568	drop by and tell us):	1005	drop by and tell us):
569		1006
570	=over 4	1007	=over 4
…		…
627	Other languages could read single lines terminated by a newline and pass	1064	Other languages could read single lines terminated by a newline and pass
628	this line into their JSON decoder of choice.	1065	this line into their JSON decoder of choice.
629		1066
630	=cut	1067	=cut
631		1068
		1069	sub json_coder() {
		1070	eval { require JSON::XS; JSON::XS->new->utf8 }
		1071	|| do { require JSON; JSON->new->utf8 }
		1072	}
		1073
632	register_write_type json => sub {	1074	register_write_type json => sub {
633	my ($self, $ref) = @_;	1075	my ($self, $ref) = @_;
634		1076
635	require JSON;	1077	my $json = $self->{json} ||= json_coder;
636		1078
637	$self->{json} ? $self->{json}->encode ($ref)	1079	$json->encode ($ref)
638	: JSON::encode_json ($ref)
639	};	1080	};
640		1081
641	=item storable => $reference	1082	=item storable => $reference
642		1083
643	Freezes the given reference using L<Storable> and writes it to the	1084	Freezes the given reference using L<Storable> and writes it to the
…		…
646	=cut	1087	=cut
647		1088
648	register_write_type storable => sub {	1089	register_write_type storable => sub {
649	my ($self, $ref) = @_;	1090	my ($self, $ref) = @_;
650		1091
651	require Storable;	1092	require Storable unless $Storable::VERSION;
652		1093
653	pack "w/a*", Storable::nfreeze ($ref)	1094	pack "w/a*", Storable::nfreeze ($ref)
654	};	1095	};
655		1096
656	=back	1097	=back
657		1098
658	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	1099	=item $handle->push_shutdown
659		1100
660	This function (not method) lets you add your own types to C<push_write>.	1101	Sometimes you know you want to close the socket after writing your data
		1102	before it was actually written. One way to do that is to replace your
		1103	C<on_drain> handler by a callback that shuts down the socket (and set
		1104	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1105	replaces the C<on_drain> callback with:
		1106
		1107	sub { shutdown $_[0]{fh}, 1 }
		1108
		1109	This simply shuts down the write side and signals an EOF condition to the
		1110	the peer.
		1111
		1112	You can rely on the normal read queue and C<on_eof> handling
		1113	afterwards. This is the cleanest way to close a connection.
		1114
		1115	This method may invoke callbacks (and therefore the handle might be
		1116	destroyed after it returns).
		1117
		1118	=cut
		1119
		1120	sub push_shutdown {
		1121	my ($self) = @_;
		1122
		1123	delete $self->{low_water_mark};
		1124	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1125	}
		1126
		1127	=item custom write types - Package::anyevent_write_type $handle, @args
		1128
		1129	Instead of one of the predefined types, you can also specify the name of
		1130	a package. AnyEvent will try to load the package and then expects to find
		1131	a function named C<anyevent_write_type> inside. If it isn't found, it
		1132	progressively tries to load the parent package until it either finds the
		1133	function (good) or runs out of packages (bad).
		1134
661	Whenever the given C<type> is used, C<push_write> will invoke the code	1135	Whenever the given C<type> is used, C<push_write> will the function with
662	reference with the handle object and the remaining arguments.	1136	the handle object and the remaining arguments.
663		1137
664	The code reference is supposed to return a single octet string that will	1138	The function is supposed to return a single octet string that will be
665	be appended to the write buffer.	1139	appended to the write buffer, so you can mentally treat this function as a
		1140	"arguments to on-the-wire-format" converter.
666		1141
667	Note that this is a function, and all types registered this way will be	1142	Example: implement a custom write type C<join> that joins the remaining
668	global, so try to use unique names.	1143	arguments using the first one.
		1144
		1145	$handle->push_write (My::Type => " ", 1,2,3);
		1146
		1147	# uses the following package, which can be defined in the "My::Type" or in
		1148	# the "My" modules to be auto-loaded, or just about anywhere when the
		1149	# My::Type::anyevent_write_type is defined before invoking it.
		1150
		1151	package My::Type;
		1152
		1153	sub anyevent_write_type {
		1154	my ($handle, $delim, @args) = @_;
		1155
		1156	join $delim, @args
		1157	}
669		1158
670	=cut	1159	=cut
671		1160
672	#############################################################################	1161	#############################################################################
673		1162
…		…
682	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1171	ways, the "simple" way, using only C<on_read> and the "complex" way, using
683	a queue.	1172	a queue.
684		1173
685	In the simple case, you just install an C<on_read> callback and whenever	1174	In the simple case, you just install an C<on_read> callback and whenever
686	new data arrives, it will be called. You can then remove some data (if	1175	new data arrives, it will be called. You can then remove some data (if
687	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna	1176	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
688	leave the data there if you want to accumulate more (e.g. when only a	1177	leave the data there if you want to accumulate more (e.g. when only a
689	partial message has been received so far).	1178	partial message has been received so far), or change the read queue with
		1179	e.g. C<push_read>.
690		1180
691	In the more complex case, you want to queue multiple callbacks. In this	1181	In the more complex case, you want to queue multiple callbacks. In this
692	case, AnyEvent::Handle will call the first queued callback each time new	1182	case, AnyEvent::Handle will call the first queued callback each time new
693	data arrives (also the first time it is queued) and removes it when it has	1183	data arrives (also the first time it is queued) and remove it when it has
694	done its job (see C<push_read>, below).	1184	done its job (see C<push_read>, below).
695		1185
696	This way you can, for example, push three line-reads, followed by reading	1186	This way you can, for example, push three line-reads, followed by reading
697	a chunk of data, and AnyEvent::Handle will execute them in order.	1187	a chunk of data, and AnyEvent::Handle will execute them in order.
698		1188
…		…
755	=cut	1245	=cut
756		1246
757	sub _drain_rbuf {	1247	sub _drain_rbuf {
758	my ($self) = @_;	1248	my ($self) = @_;
759		1249
		1250	# avoid recursion
		1251	return if $self->{_skip_drain_rbuf};
760	local $self->{_in_drain} = 1;	1252	local $self->{_skip_drain_rbuf} = 1;
761
762	if (
763	defined $self->{rbuf_max}
764	&& $self->{rbuf_max} < length $self->{rbuf}
765	) {
766	$self->_error (&Errno::ENOSPC, 1), return;
767	}
768		1253
769	while () {	1254	while () {
		1255	# we need to use a separate tls read buffer, as we must not receive data while
		1256	# we are draining the buffer, and this can only happen with TLS.
		1257	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1258	if exists $self->{_tls_rbuf};
		1259
770	my $len = length $self->{rbuf};	1260	my $len = length $self->{rbuf};
771		1261
772	if (my $cb = shift @{ $self->{_queue} }) {	1262	if (my $cb = shift @{ $self->{_queue} }) {
773	unless ($cb->($self)) {	1263	unless ($cb->($self)) {
774	if ($self->{_eof}) {	1264	# no progress can be made
775	# no progress can be made (not enough data and no data forthcoming)	1265	# (not enough data and no data forthcoming)
776	$self->_error (&Errno::EPIPE, 1), return;	1266	$self->_error (Errno::EPIPE, 1), return
777	}	1267	if $self->{_eof};
778		1268
779	unshift @{ $self->{_queue} }, $cb;	1269	unshift @{ $self->{_queue} }, $cb;
780	last;	1270	last;
781	}	1271	}
782	} elsif ($self->{on_read}) {	1272	} elsif ($self->{on_read}) {
…		…
789	&& !@{ $self->{_queue} } # and the queue is still empty	1279	&& !@{ $self->{_queue} } # and the queue is still empty
790	&& $self->{on_read} # but we still have on_read	1280	&& $self->{on_read} # but we still have on_read
791	) {	1281	) {
792	# no further data will arrive	1282	# no further data will arrive
793	# so no progress can be made	1283	# so no progress can be made
794	$self->_error (&Errno::EPIPE, 1), return	1284	$self->_error (Errno::EPIPE, 1), return
795	if $self->{_eof};	1285	if $self->{_eof};
796		1286
797	last; # more data might arrive	1287	last; # more data might arrive
798	}	1288	}
799	} else {	1289	} else {
…		…
802	last;	1292	last;
803	}	1293	}
804	}	1294	}
805		1295
806	if ($self->{_eof}) {	1296	if ($self->{_eof}) {
807	if ($self->{on_eof}) {	1297	$self->{on_eof}
808	$self->{on_eof}($self)	1298	? $self->{on_eof}($self)
809	} else {	1299	: $self->_error (0, 1, "Unexpected end-of-file");
810	$self->_error (0, 1);	1300
811	}	1301	return;
		1302	}
		1303
		1304	if (
		1305	defined $self->{rbuf_max}
		1306	&& $self->{rbuf_max} < length $self->{rbuf}
		1307	) {
		1308	$self->_error (Errno::ENOSPC, 1), return;
812	}	1309	}
813		1310
814	# may need to restart read watcher	1311	# may need to restart read watcher
815	unless ($self->{_rw}) {	1312	unless ($self->{_rw}) {
816	$self->start_read	1313	$self->start_read
…		…
822		1319
823	This replaces the currently set C<on_read> callback, or clears it (when	1320	This replaces the currently set C<on_read> callback, or clears it (when
824	the new callback is C<undef>). See the description of C<on_read> in the	1321	the new callback is C<undef>). See the description of C<on_read> in the
825	constructor.	1322	constructor.
826		1323
		1324	This method may invoke callbacks (and therefore the handle might be
		1325	destroyed after it returns).
		1326
827	=cut	1327	=cut
828		1328
829	sub on_read {	1329	sub on_read {
830	my ($self, $cb) = @_;	1330	my ($self, $cb) = @_;
831		1331
832	$self->{on_read} = $cb;	1332	$self->{on_read} = $cb;
833	$self->_drain_rbuf if $cb && !$self->{_in_drain};	1333	$self->_drain_rbuf if $cb;
834	}	1334	}
835		1335
836	=item $handle->rbuf	1336	=item $handle->rbuf
837		1337
838	Returns the read buffer (as a modifiable lvalue).	1338	Returns the read buffer (as a modifiable lvalue). You can also access the
		1339	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1340	much faster, and no less clean).
839		1341
840	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1342	The only operation allowed on the read buffer (apart from looking at it)
841	you want.	1343	is removing data from its beginning. Otherwise modifying or appending to
		1344	it is not allowed and will lead to hard-to-track-down bugs.
842		1345
843	NOTE: The read buffer should only be used or modified if the C<on_read>,	1346	NOTE: The read buffer should only be used or modified in the C<on_read>
844	C<push_read> or C<unshift_read> methods are used. The other read methods	1347	callback or when C<push_read> or C<unshift_read> are used with a single
845	automatically manage the read buffer.	1348	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1349	will manage the read buffer on their own.
846		1350
847	=cut	1351	=cut
848		1352
849	sub rbuf : lvalue {	1353	sub rbuf : lvalue {
850	$_[0]{rbuf}	1354	$_[0]{rbuf}
…		…
867		1371
868	If enough data was available, then the callback must remove all data it is	1372	If enough data was available, then the callback must remove all data it is
869	interested in (which can be none at all) and return a true value. After returning	1373	interested in (which can be none at all) and return a true value. After returning
870	true, it will be removed from the queue.	1374	true, it will be removed from the queue.
871		1375
		1376	These methods may invoke callbacks (and therefore the handle might be
		1377	destroyed after it returns).
		1378
872	=cut	1379	=cut
873		1380
874	our %RH;	1381	our %RH;
875		1382
876	sub register_read_type($$) {	1383	sub register_read_type($$) {
…		…
882	my $cb = pop;	1389	my $cb = pop;
883		1390
884	if (@_) {	1391	if (@_) {
885	my $type = shift;	1392	my $type = shift;
886		1393
		1394	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
887	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1395	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
888	->($self, $cb, @_);	1396	->($self, $cb, @_);
889	}	1397	}
890		1398
891	push @{ $self->{_queue} }, $cb;	1399	push @{ $self->{_queue} }, $cb;
892	$self->_drain_rbuf unless $self->{_in_drain};	1400	$self->_drain_rbuf;
893	}	1401	}
894		1402
895	sub unshift_read {	1403	sub unshift_read {
896	my $self = shift;	1404	my $self = shift;
897	my $cb = pop;	1405	my $cb = pop;
898		1406
899	if (@_) {	1407	if (@_) {
900	my $type = shift;	1408	my $type = shift;
901		1409
		1410	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
902	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1411	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
903	->($self, $cb, @_);	1412	->($self, $cb, @_);
904	}	1413	}
905		1414
906
907	unshift @{ $self->{_queue} }, $cb;	1415	unshift @{ $self->{_queue} }, $cb;
908	$self->_drain_rbuf unless $self->{_in_drain};	1416	$self->_drain_rbuf;
909	}	1417	}
910		1418
911	=item $handle->push_read (type => @args, $cb)	1419	=item $handle->push_read (type => @args, $cb)
912		1420
913	=item $handle->unshift_read (type => @args, $cb)	1421	=item $handle->unshift_read (type => @args, $cb)
914		1422
915	Instead of providing a callback that parses the data itself you can chose	1423	Instead of providing a callback that parses the data itself you can chose
916	between a number of predefined parsing formats, for chunks of data, lines	1424	between a number of predefined parsing formats, for chunks of data, lines
917	etc.	1425	etc. You can also specify the (fully qualified) name of a package, in
		1426	which case AnyEvent tries to load the package and then expects to find the
		1427	C<anyevent_read_type> function inside (see "custom read types", below).
918		1428
919	Predefined types are (if you have ideas for additional types, feel free to	1429	Predefined types are (if you have ideas for additional types, feel free to
920	drop by and tell us):	1430	drop by and tell us):
921		1431
922	=over 4	1432	=over 4
…		…
928	data.	1438	data.
929		1439
930	Example: read 2 bytes.	1440	Example: read 2 bytes.
931		1441
932	$handle->push_read (chunk => 2, sub {	1442	$handle->push_read (chunk => 2, sub {
933	warn "yay ", unpack "H*", $_[1];	1443	say "yay " . unpack "H*", $_[1];
934	});	1444	});
935		1445
936	=cut	1446	=cut
937		1447
938	register_read_type chunk => sub {	1448	register_read_type chunk => sub {
…		…
972	if (@_ < 3) {	1482	if (@_ < 3) {
973	# this is more than twice as fast as the generic code below	1483	# this is more than twice as fast as the generic code below
974	sub {	1484	sub {
975	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;	1485	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
976		1486
977	$cb->($_[0], $1, $2);	1487	$cb->($_[0], "$1", "$2");
978	1	1488	1
979	}	1489	}
980	} else {	1490	} else {
981	$eol = quotemeta $eol unless ref $eol;	1491	$eol = quotemeta $eol unless ref $eol;
982	$eol = qr|^(.*?)($eol)|s;	1492	$eol = qr|^(.*?)($eol)|s;
983		1493
984	sub {	1494	sub {
985	$_[0]{rbuf} =~ s/$eol// or return;	1495	$_[0]{rbuf} =~ s/$eol// or return;
986		1496
987	$cb->($_[0], $1, $2);	1497	$cb->($_[0], "$1", "$2");
988	1	1498	1
989	}	1499	}
990	}	1500	}
991	};	1501	};
992		1502
…		…
1014	the receive buffer when neither C<$accept> nor C<$reject> match,	1524	the receive buffer when neither C<$accept> nor C<$reject> match,
1015	and everything preceding and including the match will be accepted	1525	and everything preceding and including the match will be accepted
1016	unconditionally. This is useful to skip large amounts of data that you	1526	unconditionally. This is useful to skip large amounts of data that you
1017	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1527	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1018	have to start matching from the beginning. This is purely an optimisation	1528	have to start matching from the beginning. This is purely an optimisation
1019	and is usually worth only when you expect more than a few kilobytes.	1529	and is usually worth it only when you expect more than a few kilobytes.
1020		1530
1021	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1531	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1022	expect the header to be very large (it isn't in practise, but...), we use	1532	expect the header to be very large (it isn't in practice, but...), we use
1023	a skip regex to skip initial portions. The skip regex is tricky in that	1533	a skip regex to skip initial portions. The skip regex is tricky in that
1024	it only accepts something not ending in either \015 or \012, as these are	1534	it only accepts something not ending in either \015 or \012, as these are
1025	required for the accept regex.	1535	required for the accept regex.
1026		1536
1027	$handle->push_read (regex =>	1537	$handle->push_read (regex =>
…		…
1040		1550
1041	sub {	1551	sub {
1042	# accept	1552	# accept
1043	if ($$rbuf =~ $accept) {	1553	if ($$rbuf =~ $accept) {
1044	$data .= substr $$rbuf, 0, $+[0], "";	1554	$data .= substr $$rbuf, 0, $+[0], "";
1045	$cb->($self, $data);	1555	$cb->($_[0], $data);
1046	return 1;	1556	return 1;
1047	}	1557	}
1048		1558
1049	# reject	1559	# reject
1050	if ($reject && $$rbuf =~ $reject) {	1560	if ($reject && $$rbuf =~ $reject) {
1051	$self->_error (&Errno::EBADMSG);	1561	$_[0]->_error (Errno::EBADMSG);
1052	}	1562	}
1053		1563
1054	# skip	1564	# skip
1055	if ($skip && $$rbuf =~ $skip) {	1565	if ($skip && $$rbuf =~ $skip) {
1056	$data .= substr $$rbuf, 0, $+[0], "";	1566	$data .= substr $$rbuf, 0, $+[0], "";
…		…
1072	my ($self, $cb) = @_;	1582	my ($self, $cb) = @_;
1073		1583
1074	sub {	1584	sub {
1075	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1585	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1076	if ($_[0]{rbuf} =~ /[^0-9]/) {	1586	if ($_[0]{rbuf} =~ /[^0-9]/) {
1077	$self->_error (&Errno::EBADMSG);	1587	$_[0]->_error (Errno::EBADMSG);
1078	}	1588	}
1079	return;	1589	return;
1080	}	1590	}
1081		1591
1082	my $len = $1;	1592	my $len = $1;
1083		1593
1084	$self->unshift_read (chunk => $len, sub {	1594	$_[0]->unshift_read (chunk => $len, sub {
1085	my $string = $_[1];	1595	my $string = $_[1];
1086	$_[0]->unshift_read (chunk => 1, sub {	1596	$_[0]->unshift_read (chunk => 1, sub {
1087	if ($_[1] eq ",") {	1597	if ($_[1] eq ",") {
1088	$cb->($_[0], $string);	1598	$cb->($_[0], $string);
1089	} else {	1599	} else {
1090	$self->_error (&Errno::EBADMSG);	1600	$_[0]->_error (Errno::EBADMSG);
1091	}	1601	}
1092	});	1602	});
1093	});	1603	});
1094		1604
1095	1	1605	1
…		…
1142	}	1652	}
1143	};	1653	};
1144		1654
1145	=item json => $cb->($handle, $hash_or_arrayref)	1655	=item json => $cb->($handle, $hash_or_arrayref)
1146		1656
1147	Reads a JSON object or array, decodes it and passes it to the callback.	1657	Reads a JSON object or array, decodes it and passes it to the
		1658	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1148		1659
1149	If a C<json> object was passed to the constructor, then that will be used	1660	If a C<json> object was passed to the constructor, then that will be used
1150	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1661	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1151		1662
1152	This read type uses the incremental parser available with JSON version	1663	This read type uses the incremental parser available with JSON version
…		…
1161	=cut	1672	=cut
1162		1673
1163	register_read_type json => sub {	1674	register_read_type json => sub {
1164	my ($self, $cb) = @_;	1675	my ($self, $cb) = @_;
1165		1676
1166	require JSON;	1677	my $json = $self->{json} ||= json_coder;
1167		1678
1168	my $data;	1679	my $data;
1169	my $rbuf = \$self->{rbuf};	1680	my $rbuf = \$self->{rbuf};
1170		1681
1171	my $json = $self->{json} ||= JSON->new->utf8;
1172
1173	sub {	1682	sub {
1174	my $ref = $json->incr_parse ($self->{rbuf});	1683	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1175		1684
1176	if ($ref) {	1685	if ($ref) {
1177	$self->{rbuf} = $json->incr_text;	1686	$_[0]{rbuf} = $json->incr_text;
1178	$json->incr_text = "";	1687	$json->incr_text = "";
1179	$cb->($self, $ref);	1688	$cb->($_[0], $ref);
1180		1689
1181	1	1690	1
		1691	} elsif ($@) {
		1692	# error case
		1693	$json->incr_skip;
		1694
		1695	$_[0]{rbuf} = $json->incr_text;
		1696	$json->incr_text = "";
		1697
		1698	$_[0]->_error (Errno::EBADMSG);
		1699
		1700	()
1182	} else {	1701	} else {
1183	$self->{rbuf} = "";	1702	$_[0]{rbuf} = "";
		1703
1184	()	1704	()
1185	}	1705	}
1186	}	1706	}
1187	};	1707	};
1188		1708
…		…
1197	=cut	1717	=cut
1198		1718
1199	register_read_type storable => sub {	1719	register_read_type storable => sub {
1200	my ($self, $cb) = @_;	1720	my ($self, $cb) = @_;
1201		1721
1202	require Storable;	1722	require Storable unless $Storable::VERSION;
1203		1723
1204	sub {	1724	sub {
1205	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method	1725	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1206	defined (my $len = eval { unpack "w", $_[0]{rbuf} })	1726	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1207	or return;	1727	or return;
…		…
1220	# read remaining chunk	1740	# read remaining chunk
1221	$_[0]->unshift_read (chunk => $len, sub {	1741	$_[0]->unshift_read (chunk => $len, sub {
1222	if (my $ref = eval { Storable::thaw ($_[1]) }) {	1742	if (my $ref = eval { Storable::thaw ($_[1]) }) {
1223	$cb->($_[0], $ref);	1743	$cb->($_[0], $ref);
1224	} else {	1744	} else {
1225	$self->_error (&Errno::EBADMSG);	1745	$_[0]->_error (Errno::EBADMSG);
1226	}	1746	}
1227	});	1747	});
1228	}	1748	}
1229		1749
1230	1	1750	1
1231	}	1751	}
1232	};	1752	};
1233		1753
1234	=back	1754	=back
1235		1755
1236	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)	1756	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1237		1757
1238	This function (not method) lets you add your own types to C<push_read>.	1758	Instead of one of the predefined types, you can also specify the name
		1759	of a package. AnyEvent will try to load the package and then expects to
		1760	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1761	progressively tries to load the parent package until it either finds the
		1762	function (good) or runs out of packages (bad).
1239		1763
1240	Whenever the given C<type> is used, C<push_read> will invoke the code	1764	Whenever this type is used, C<push_read> will invoke the function with the
1241	reference with the handle object, the callback and the remaining	1765	handle object, the original callback and the remaining arguments.
1242	arguments.
1243		1766
1244	The code reference is supposed to return a callback (usually a closure)	1767	The function is supposed to return a callback (usually a closure) that
1245	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1768	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1769	mentally treat the function as a "configurable read type to read callback"
		1770	converter.
1246		1771
1247	It should invoke the passed callback when it is done reading (remember to	1772	It should invoke the original callback when it is done reading (remember
1248	pass C<$handle> as first argument as all other callbacks do that).	1773	to pass C<$handle> as first argument as all other callbacks do that,
		1774	although there is no strict requirement on this).
1249		1775
1250	Note that this is a function, and all types registered this way will be
1251	global, so try to use unique names.
1252
1253	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1776	For examples, see the source of this module (F<perldoc -m
1254	search for C<register_read_type>)).	1777	AnyEvent::Handle>, search for C<register_read_type>)).
1255		1778
1256	=item $handle->stop_read	1779	=item $handle->stop_read
1257		1780
1258	=item $handle->start_read	1781	=item $handle->start_read
1259		1782
…		…
1265	Note that AnyEvent::Handle will automatically C<start_read> for you when	1788	Note that AnyEvent::Handle will automatically C<start_read> for you when
1266	you change the C<on_read> callback or push/unshift a read callback, and it	1789	you change the C<on_read> callback or push/unshift a read callback, and it
1267	will automatically C<stop_read> for you when neither C<on_read> is set nor	1790	will automatically C<stop_read> for you when neither C<on_read> is set nor
1268	there are any read requests in the queue.	1791	there are any read requests in the queue.
1269		1792
1270	These methods will have no effect when in TLS mode (as TLS doesn't support	1793	In older versions of this module (<= 5.3), these methods had no effect,
1271	half-duplex connections).	1794	as TLS does not support half-duplex connections. In current versions they
		1795	work as expected, as this behaviour is required to avoid certain resource
		1796	attacks, where the program would be forced to read (and buffer) arbitrary
		1797	amounts of data before being able to send some data. The drawback is that
		1798	some readings of the the SSL/TLS specifications basically require this
		1799	attack to be working, as SSL/TLS implementations might stall sending data
		1800	during a rehandshake.
		1801
		1802	As a guideline, during the initial handshake, you should not stop reading,
		1803	and as a client, it might cause problems, depending on your application.
1272		1804
1273	=cut	1805	=cut
1274		1806
1275	sub stop_read {	1807	sub stop_read {
1276	my ($self) = @_;	1808	my ($self) = @_;
1277		1809
1278	delete $self->{_rw} unless $self->{tls};	1810	delete $self->{_rw};
1279	}	1811	}
1280		1812
1281	sub start_read {	1813	sub start_read {
1282	my ($self) = @_;	1814	my ($self) = @_;
1283		1815
1284	unless ($self->{_rw} || $self->{_eof}) {	1816	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1285	Scalar::Util::weaken $self;	1817	Scalar::Util::weaken $self;
1286		1818
1287	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1819	$self->{_rw} = AE::io $self->{fh}, 0, sub {
1288	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});	1820	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1289	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1821	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1290		1822
1291	if ($len > 0) {	1823	if ($len > 0) {
1292	$self->{_activity} = AnyEvent->now;	1824	$self->{_activity} = $self->{_ractivity} = AE::now;
1293		1825
1294	if ($self->{tls}) {	1826	if ($self->{tls}) {
1295	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);	1827	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1828
1296	&_dotls ($self);	1829	&_dotls ($self);
1297	} else {	1830	} else {
1298	$self->_drain_rbuf unless $self->{_in_drain};	1831	$self->_drain_rbuf;
		1832	}
		1833
		1834	if ($len == $self->{read_size}) {
		1835	$self->{read_size} *= 2;
		1836	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1837	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1299	}	1838	}
1300		1839
1301	} elsif (defined $len) {	1840	} elsif (defined $len) {
1302	delete $self->{_rw};	1841	delete $self->{_rw};
1303	$self->{_eof} = 1;	1842	$self->{_eof} = 1;
1304	$self->_drain_rbuf unless $self->{_in_drain};	1843	$self->_drain_rbuf;
1305		1844
1306	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1845	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1307	return $self->_error ($!, 1);	1846	return $self->_error ($!, 1);
1308	}	1847	}
1309	});	1848	};
1310	}	1849	}
1311	}	1850	}
1312		1851
		1852	our $ERROR_SYSCALL;
		1853	our $ERROR_WANT_READ;
		1854
		1855	sub _tls_error {
		1856	my ($self, $err) = @_;
		1857
		1858	return $self->_error ($!, 1)
		1859	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1860
		1861	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1862
		1863	# reduce error string to look less scary
		1864	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1865
		1866	if ($self->{_on_starttls}) {
		1867	(delete $self->{_on_starttls})->($self, undef, $err);
		1868	&_freetls;
		1869	} else {
		1870	&_freetls;
		1871	$self->_error (Errno::EPROTO, 1, $err);
		1872	}
		1873	}
		1874
		1875	# poll the write BIO and send the data if applicable
		1876	# also decode read data if possible
		1877	# this is basiclaly our TLS state machine
		1878	# more efficient implementations are possible with openssl,
		1879	# but not with the buggy and incomplete Net::SSLeay.
1313	sub _dotls {	1880	sub _dotls {
1314	my ($self) = @_;	1881	my ($self) = @_;
1315		1882
1316	my $buf;	1883	my $tmp;
1317		1884
1318	if (length $self->{_tls_wbuf}) {	1885	if (length $self->{_tls_wbuf}) {
1319	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1886	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1320	substr $self->{_tls_wbuf}, 0, $len, "";	1887	substr $self->{_tls_wbuf}, 0, $tmp, "";
1321	}	1888	}
1322	}
1323		1889
		1890	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1891	return $self->_tls_error ($tmp)
		1892	if $tmp != $ERROR_WANT_READ
		1893	&& ($tmp != $ERROR_SYSCALL || $!);
		1894	}
		1895
1324	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1896	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1325	unless (length $buf) {	1897	unless (length $tmp) {
1326	# let's treat SSL-eof as we treat normal EOF	1898	$self->{_on_starttls}
1327	delete $self->{_rw};	1899	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1328	$self->{_eof} = 1;
1329	&_freetls;	1900	&_freetls;
		1901
		1902	if ($self->{on_stoptls}) {
		1903	$self->{on_stoptls}($self);
		1904	return;
		1905	} else {
		1906	# let's treat SSL-eof as we treat normal EOF
		1907	delete $self->{_rw};
		1908	$self->{_eof} = 1;
		1909	}
1330	}	1910	}
1331		1911
1332	$self->{rbuf} .= $buf;	1912	$self->{_tls_rbuf} .= $tmp;
1333	$self->_drain_rbuf unless $self->{_in_drain};	1913	$self->_drain_rbuf;
1334	$self->{tls} or return; # tls session might have gone away in callback	1914	$self->{tls} or return; # tls session might have gone away in callback
1335	}	1915	}
1336		1916
1337	my $err = Net::SSLeay::get_error ($self->{tls}, -1);	1917	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1338
1339	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1340	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1341	return $self->_error ($!, 1);	1918	return $self->_tls_error ($tmp)
1342	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1919	if $tmp != $ERROR_WANT_READ
1343	return $self->_error (&Errno::EIO, 1);	1920	&& ($tmp != $ERROR_SYSCALL || $!);
1344	}
1345		1921
1346	# all others are fine for our purposes
1347	}
1348
1349	while (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1922	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1350	$self->{wbuf} .= $buf;	1923	$self->{wbuf} .= $tmp;
1351	$self->_drain_wbuf;	1924	$self->_drain_wbuf;
		1925	$self->{tls} or return; # tls session might have gone away in callback
1352	}	1926	}
		1927
		1928	$self->{_on_starttls}
		1929	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
		1930	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1353	}	1931	}
1354		1932
1355	=item $handle->starttls ($tls[, $tls_ctx])	1933	=item $handle->starttls ($tls[, $tls_ctx])
1356		1934
1357	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1935	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1358	object is created, you can also do that at a later time by calling	1936	object is created, you can also do that at a later time by calling
1359	C<starttls>.	1937	C<starttls>.
1360		1938
		1939	Starting TLS is currently an asynchronous operation - when you push some
		1940	write data and then call C<< ->starttls >> then TLS negotiation will start
		1941	immediately, after which the queued write data is then sent.
		1942
1361	The first argument is the same as the C<tls> constructor argument (either	1943	The first argument is the same as the C<tls> constructor argument (either
1362	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1944	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1363		1945
1364	The second argument is the optional C<Net::SSLeay::CTX> object that is	1946	The second argument is the optional C<AnyEvent::TLS> object that is used
1365	used when AnyEvent::Handle has to create its own TLS connection object.	1947	when AnyEvent::Handle has to create its own TLS connection object, or
		1948	a hash reference with C<< key => value >> pairs that will be used to
		1949	construct a new context.
1366		1950
1367	The TLS connection object will end up in C<< $handle->{tls} >> after this	1951	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1368	call and can be used or changed to your liking. Note that the handshake	1952	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1369	might have already started when this function returns.	1953	changed to your liking. Note that the handshake might have already started
		1954	when this function returns.
1370		1955
1371	If it an error to start a TLS handshake more than once per	1956	Due to bugs in OpenSSL, it might or might not be possible to do multiple
1372	AnyEvent::Handle object (this is due to bugs in OpenSSL).	1957	handshakes on the same stream. It is best to not attempt to use the
		1958	stream after stopping TLS.
1373		1959
		1960	This method may invoke callbacks (and therefore the handle might be
		1961	destroyed after it returns).
		1962
1374	=cut	1963	=cut
		1964
		1965	our %TLS_CACHE; #TODO not yet documented, should we?
1375		1966
1376	sub starttls {	1967	sub starttls {
1377	my ($self, $ssl, $ctx) = @_;	1968	my ($self, $tls, $ctx) = @_;
		1969
		1970	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1971	if $self->{tls};
		1972
		1973	$self->{tls} = $tls;
		1974	$self->{tls_ctx} = $ctx if @_ > 2;
		1975
		1976	return unless $self->{fh};
1378		1977
1379	require Net::SSLeay;	1978	require Net::SSLeay;
1380		1979
1381	Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object"	1980	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1382	if $self->{tls};	1981	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1982
		1983	$tls = delete $self->{tls};
		1984	$ctx = $self->{tls_ctx};
		1985
		1986	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1987
		1988	if ("HASH" eq ref $ctx) {
		1989	require AnyEvent::TLS;
		1990
		1991	if ($ctx->{cache}) {
		1992	my $key = $ctx+0;
		1993	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1994	} else {
		1995	$ctx = new AnyEvent::TLS %$ctx;
		1996	}
		1997	}
1383		1998
1384	if ($ssl eq "accept") {	1999	$self->{tls_ctx} = $ctx || TLS_CTX ();
1385	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	2000	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1386	Net::SSLeay::set_accept_state ($ssl);
1387	} elsif ($ssl eq "connect") {
1388	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1389	Net::SSLeay::set_connect_state ($ssl);
1390	}
1391
1392	$self->{tls} = $ssl;
1393		2001
1394	# basically, this is deep magic (because SSL_read should have the same issues)	2002	# basically, this is deep magic (because SSL_read should have the same issues)
1395	# but the openssl maintainers basically said: "trust us, it just works".	2003	# but the openssl maintainers basically said: "trust us, it just works".
1396	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	2004	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1397	# and mismaintained ssleay-module doesn't even offer them).	2005	# and mismaintained ssleay-module doesn't even offer them).
…		…
1401	#	2009	#
1402	# note that we do not try to keep the length constant between writes as we are required to do.	2010	# note that we do not try to keep the length constant between writes as we are required to do.
1403	# we assume that most (but not all) of this insanity only applies to non-blocking cases,	2011	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
1404	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to	2012	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1405	# have identity issues in that area.	2013	# have identity issues in that area.
1406	Net::SSLeay::CTX_set_mode ($self->{tls},	2014	# Net::SSLeay::CTX_set_mode ($ssl,
1407	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2015	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1408	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2016	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		2017	Net::SSLeay::CTX_set_mode ($tls, 1|2);
1409		2018
1410	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2019	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1411	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2020	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1412		2021
		2022	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2023	$self->{rbuf} = "";
		2024
1413	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	2025	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
		2026
		2027	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
		2028	if $self->{on_starttls};
1414		2029
1415	&_dotls; # need to trigger the initial handshake	2030	&_dotls; # need to trigger the initial handshake
1416	$self->start_read; # make sure we actually do read	2031	$self->start_read; # make sure we actually do read
1417	}	2032	}
1418		2033
1419	=item $handle->stoptls	2034	=item $handle->stoptls
1420		2035
1421	Shuts down the SSL connection - this makes a proper EOF handshake by	2036	Shuts down the SSL connection - this makes a proper EOF handshake by
1422	sending a close notify to the other side, but since OpenSSL doesn't	2037	sending a close notify to the other side, but since OpenSSL doesn't
1423	support non-blocking shut downs, it is not possible to re-use the stream	2038	support non-blocking shut downs, it is not guaranteed that you can re-use
1424	afterwards.	2039	the stream afterwards.
		2040
		2041	This method may invoke callbacks (and therefore the handle might be
		2042	destroyed after it returns).
1425		2043
1426	=cut	2044	=cut
1427		2045
1428	sub stoptls {	2046	sub stoptls {
1429	my ($self) = @_;	2047	my ($self) = @_;
1430		2048
1431	if ($self->{tls}) {	2049	if ($self->{tls} && $self->{fh}) {
1432	Net::SSLeay::shutdown ($self->{tls});	2050	Net::SSLeay::shutdown ($self->{tls});
1433		2051
1434	&_dotls;	2052	&_dotls;
1435		2053
1436	# we don't give a shit. no, we do, but we can't. no...	2054	# # we don't give a shit. no, we do, but we can't. no...#d#
1437	# we, we... have to use openssl :/	2055	# # we, we... have to use openssl :/#d#
1438	&_freetls;	2056	# &_freetls;#d#
1439	}	2057	}
1440	}	2058	}
1441		2059
1442	sub _freetls {	2060	sub _freetls {
1443	my ($self) = @_;	2061	my ($self) = @_;
1444		2062
1445	return unless $self->{tls};	2063	return unless $self->{tls};
1446		2064
1447	Net::SSLeay::free (delete $self->{tls});	2065	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2066	if $self->{tls} > 0;
1448		2067
1449	delete @$self{qw(_rbio _wbio _tls_wbuf)};	2068	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1450	}	2069	}
		2070
		2071	=item $handle->resettls
		2072
		2073	This rarely-used method simply resets and TLS state on the handle, usually
		2074	causing data loss.
		2075
		2076	One case where it may be useful is when you want to skip over the data in
		2077	the stream but you are not interested in interpreting it, so data loss is
		2078	no concern.
		2079
		2080	=cut
		2081
		2082	*resettls = \&_freetls;
1451		2083
1452	sub DESTROY {	2084	sub DESTROY {
1453	my $self = shift;	2085	my ($self) = @_;
1454		2086
1455	&_freetls;	2087	&_freetls;
1456		2088
1457	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	2089	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1458		2090
1459	if ($linger && length $self->{wbuf}) {	2091	if ($linger && length $self->{wbuf} && $self->{fh}) {
1460	my $fh = delete $self->{fh};	2092	my $fh = delete $self->{fh};
1461	my $wbuf = delete $self->{wbuf};	2093	my $wbuf = delete $self->{wbuf};
1462		2094
1463	my @linger;	2095	my @linger;
1464		2096
1465	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {	2097	push @linger, AE::io $fh, 1, sub {
1466	my $len = syswrite $fh, $wbuf, length $wbuf;	2098	my $len = syswrite $fh, $wbuf, length $wbuf;
1467		2099
1468	if ($len > 0) {	2100	if ($len > 0) {
1469	substr $wbuf, 0, $len, "";	2101	substr $wbuf, 0, $len, "";
1470	} else {	2102	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1471	@linger = (); # end	2103	@linger = (); # end
1472	}	2104	}
		2105	};
		2106	push @linger, AE::timer $linger, 0, sub {
		2107	@linger = ();
		2108	};
		2109	}
		2110	}
		2111
		2112	=item $handle->destroy
		2113
		2114	Shuts down the handle object as much as possible - this call ensures that
		2115	no further callbacks will be invoked and as many resources as possible
		2116	will be freed. Any method you will call on the handle object after
		2117	destroying it in this way will be silently ignored (and it will return the
		2118	empty list).
		2119
		2120	Normally, you can just "forget" any references to an AnyEvent::Handle
		2121	object and it will simply shut down. This works in fatal error and EOF
		2122	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2123	callback, so when you want to destroy the AnyEvent::Handle object from
		2124	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2125	that case.
		2126
		2127	Destroying the handle object in this way has the advantage that callbacks
		2128	will be removed as well, so if those are the only reference holders (as
		2129	is common), then one doesn't need to do anything special to break any
		2130	reference cycles.
		2131
		2132	The handle might still linger in the background and write out remaining
		2133	data, as specified by the C<linger> option, however.
		2134
		2135	=cut
		2136
		2137	sub destroy {
		2138	my ($self) = @_;
		2139
		2140	$self->DESTROY;
		2141	%$self = ();
		2142	bless $self, "AnyEvent::Handle::destroyed";
		2143	}
		2144
		2145	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2146	#nop
		2147	}
		2148
		2149	=item $handle->destroyed
		2150
		2151	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2152	->destroy >>, true otherwise.
		2153
		2154	Can be useful to decide whether the handle is still valid after some
		2155	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2156	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2157	can destroy the handle, so work can be avoided by checking sometimes:
		2158
		2159	$hdl->starttls ("accept");
		2160	return if $hdl->destroyed;
		2161	$hdl->push_write (...
		2162
		2163	Note that the call to C<push_write> will silently be ignored if the handle
		2164	has been destroyed, so often you can just ignore the possibility of the
		2165	handle being destroyed.
		2166
		2167	=cut
		2168
		2169	sub destroyed { 0 }
		2170	sub AnyEvent::Handle::destroyed::destroyed { 1 }
		2171
		2172	=item AnyEvent::Handle::TLS_CTX
		2173
		2174	This function creates and returns the AnyEvent::TLS object used by default
		2175	for TLS mode.
		2176
		2177	The context is created by calling L<AnyEvent::TLS> without any arguments.
		2178
		2179	=cut
		2180
		2181	our $TLS_CTX;
		2182
		2183	sub TLS_CTX() {
		2184	$TLS_CTX ||= do {
		2185	require AnyEvent::TLS;
		2186
		2187	new AnyEvent::TLS
		2188	}
		2189	}
		2190
		2191	=back
		2192
		2193
		2194	=head1 NONFREQUENTLY ASKED QUESTIONS
		2195
		2196	=over 4
		2197
		2198	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2199	still get further invocations!
		2200
		2201	That's because AnyEvent::Handle keeps a reference to itself when handling
		2202	read or write callbacks.
		2203
		2204	It is only safe to "forget" the reference inside EOF or error callbacks,
		2205	from within all other callbacks, you need to explicitly call the C<<
		2206	->destroy >> method.
		2207
		2208	=item Why is my C<on_eof> callback never called?
		2209
		2210	Probably because your C<on_error> callback is being called instead: When
		2211	you have outstanding requests in your read queue, then an EOF is
		2212	considered an error as you clearly expected some data.
		2213
		2214	To avoid this, make sure you have an empty read queue whenever your handle
		2215	is supposed to be "idle" (i.e. connection closes are O.K.). You can set
		2216	an C<on_read> handler that simply pushes the first read requests in the
		2217	queue.
		2218
		2219	See also the next question, which explains this in a bit more detail.
		2220
		2221	=item How can I serve requests in a loop?
		2222
		2223	Most protocols consist of some setup phase (authentication for example)
		2224	followed by a request handling phase, where the server waits for requests
		2225	and handles them, in a loop.
		2226
		2227	There are two important variants: The first (traditional, better) variant
		2228	handles requests until the server gets some QUIT command, causing it to
		2229	close the connection first (highly desirable for a busy TCP server). A
		2230	client dropping the connection is an error, which means this variant can
		2231	detect an unexpected detection close.
		2232
		2233	To handle this case, always make sure you have a on-empty read queue, by
		2234	pushing the "read request start" handler on it:
		2235
		2236	# we assume a request starts with a single line
		2237	my @start_request; @start_request = (line => sub {
		2238	my ($hdl, $line) = @_;
		2239
		2240	... handle request
		2241
		2242	# push next request read, possibly from a nested callback
		2243	$hdl->push_read (@start_request);
		2244	});
		2245
		2246	# auth done, now go into request handling loop
		2247	# now push the first @start_request
		2248	$hdl->push_read (@start_request);
		2249
		2250	By always having an outstanding C<push_read>, the handle always expects
		2251	some data and raises the C<EPIPE> error when the connction is dropped
		2252	unexpectedly.
		2253
		2254	The second variant is a protocol where the client can drop the connection
		2255	at any time. For TCP, this means that the server machine may run out of
		2256	sockets easier, and in general, it means you cannot distinguish a protocl
		2257	failure/client crash from a normal connection close. Nevertheless, these
		2258	kinds of protocols are common (and sometimes even the best solution to the
		2259	problem).
		2260
		2261	Having an outstanding read request at all times is possible if you ignore
		2262	C<EPIPE> errors, but this doesn't help with when the client drops the
		2263	connection during a request, which would still be an error.
		2264
		2265	A better solution is to push the initial request read in an C<on_read>
		2266	callback. This avoids an error, as when the server doesn't expect data
		2267	(i.e. is idly waiting for the next request, an EOF will not raise an
		2268	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2269	and simpler:
		2270
		2271	# auth done, now go into request handling loop
		2272	$hdl->on_read (sub {
		2273	my ($hdl) = @_;
		2274
		2275	# called each time we receive data but the read queue is empty
		2276	# simply start read the request
		2277
		2278	$hdl->push_read (line => sub {
		2279	my ($hdl, $line) = @_;
		2280
		2281	... handle request
		2282
		2283	# do nothing special when the request has been handled, just
		2284	# let the request queue go empty.
1473	});	2285	});
1474	push @linger, AnyEvent->timer (after => $linger, cb => sub {
1475	@linger = ();
1476	});	2286	});
1477	}
1478	}
1479		2287
1480	=item AnyEvent::Handle::TLS_CTX	2288	=item I get different callback invocations in TLS mode/Why can't I pause
		2289	reading?
1481		2290
1482	This function creates and returns the Net::SSLeay::CTX object used by	2291	Unlike, say, TCP, TLS connections do not consist of two independent
1483	default for TLS mode.	2292	communication channels, one for each direction. Or put differently, the
		2293	read and write directions are not independent of each other: you cannot
		2294	write data unless you are also prepared to read, and vice versa.
1484		2295
1485	The context is created like this:	2296	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2297	callback invocations when you are not expecting any read data - the reason
		2298	is that AnyEvent::Handle always reads in TLS mode.
1486		2299
1487	Net::SSLeay::load_error_strings;	2300	During the connection, you have to make sure that you always have a
1488	Net::SSLeay::SSLeay_add_ssl_algorithms;	2301	non-empty read-queue, or an C<on_read> watcher. At the end of the
1489	Net::SSLeay::randomize;	2302	connection (or when you no longer want to use it) you can call the
1490		2303	C<destroy> method.
1491	my $CTX = Net::SSLeay::CTX_new;
1492
1493	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1494
1495	=cut
1496
1497	our $TLS_CTX;
1498
1499	sub TLS_CTX() {
1500	$TLS_CTX || do {
1501	require Net::SSLeay;
1502
1503	Net::SSLeay::load_error_strings ();
1504	Net::SSLeay::SSLeay_add_ssl_algorithms ();
1505	Net::SSLeay::randomize ();
1506
1507	$TLS_CTX = Net::SSLeay::CTX_new ();
1508
1509	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1510
1511	$TLS_CTX
1512	}
1513	}
1514
1515	=back
1516
1517
1518	=head1 NONFREQUENTLY ASKED QUESTIONS
1519
1520	=over 4
1521		2304
1522	=item How do I read data until the other side closes the connection?	2305	=item How do I read data until the other side closes the connection?
1523		2306
1524	If you just want to read your data into a perl scalar, the easiest way	2307	If you just want to read your data into a perl scalar, the easiest way
1525	to achieve this is by setting an C<on_read> callback that does nothing,	2308	to achieve this is by setting an C<on_read> callback that does nothing,
…		…
1528		2311
1529	$handle->on_read (sub { });	2312	$handle->on_read (sub { });
1530	$handle->on_eof (undef);	2313	$handle->on_eof (undef);
1531	$handle->on_error (sub {	2314	$handle->on_error (sub {
1532	my $data = delete $_[0]{rbuf};	2315	my $data = delete $_[0]{rbuf};
1533	undef $handle;
1534	});	2316	});
		2317
		2318	Note that this example removes the C<rbuf> member from the handle object,
		2319	which is not normally allowed by the API. It is expressly permitted in
		2320	this case only, as the handle object needs to be destroyed afterwards.
1535		2321
1536	The reason to use C<on_error> is that TCP connections, due to latencies	2322	The reason to use C<on_error> is that TCP connections, due to latencies
1537	and packets loss, might get closed quite violently with an error, when in	2323	and packets loss, might get closed quite violently with an error, when in
1538	fact, all data has been received.	2324	fact all data has been received.
1539		2325
1540	It is usually better to use acknowledgements when transfering data,	2326	It is usually better to use acknowledgements when transferring data,
1541	to make sure the other side hasn't just died and you got the data	2327	to make sure the other side hasn't just died and you got the data
1542	intact. This is also one reason why so many internet protocols have an	2328	intact. This is also one reason why so many internet protocols have an
1543	explicit QUIT command.	2329	explicit QUIT command.
1544
1545		2330
1546	=item I don't want to destroy the handle too early - how do I wait until	2331	=item I don't want to destroy the handle too early - how do I wait until
1547	all data has been written?	2332	all data has been written?
1548		2333
1549	After writing your last bits of data, set the C<on_drain> callback	2334	After writing your last bits of data, set the C<on_drain> callback
…		…
1551	C<low_water_mark> this will be called precisely when all data has been	2336	C<low_water_mark> this will be called precisely when all data has been
1552	written to the socket:	2337	written to the socket:
1553		2338
1554	$handle->push_write (...);	2339	$handle->push_write (...);
1555	$handle->on_drain (sub {	2340	$handle->on_drain (sub {
1556	warn "all data submitted to the kernel\n";	2341	AE::log debug => "all data submitted to the kernel\n";
1557	undef $handle;	2342	undef $handle;
1558	});	2343	});
		2344
		2345	If you just want to queue some data and then signal EOF to the other side,
		2346	consider using C<< ->push_shutdown >> instead.
		2347
		2348	=item I want to contact a TLS/SSL server, I don't care about security.
		2349
		2350	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2351	connect to it and then create the AnyEvent::Handle with the C<tls>
		2352	parameter:
		2353
		2354	tcp_connect $host, $port, sub {
		2355	my ($fh) = @_;
		2356
		2357	my $handle = new AnyEvent::Handle
		2358	fh => $fh,
		2359	tls => "connect",
		2360	on_error => sub { ... };
		2361
		2362	$handle->push_write (...);
		2363	};
		2364
		2365	=item I want to contact a TLS/SSL server, I do care about security.
		2366
		2367	Then you should additionally enable certificate verification, including
		2368	peername verification, if the protocol you use supports it (see
		2369	L<AnyEvent::TLS>, C<verify_peername>).
		2370
		2371	E.g. for HTTPS:
		2372
		2373	tcp_connect $host, $port, sub {
		2374	my ($fh) = @_;
		2375
		2376	my $handle = new AnyEvent::Handle
		2377	fh => $fh,
		2378	peername => $host,
		2379	tls => "connect",
		2380	tls_ctx => { verify => 1, verify_peername => "https" },
		2381	...
		2382
		2383	Note that you must specify the hostname you connected to (or whatever
		2384	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2385	peername verification will be done.
		2386
		2387	The above will use the system-dependent default set of trusted CA
		2388	certificates. If you want to check against a specific CA, add the
		2389	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2390
		2391	tls_ctx => {
		2392	verify => 1,
		2393	verify_peername => "https",
		2394	ca_file => "my-ca-cert.pem",
		2395	},
		2396
		2397	=item I want to create a TLS/SSL server, how do I do that?
		2398
		2399	Well, you first need to get a server certificate and key. You have
		2400	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2401	self-signed certificate (cheap. check the search engine of your choice,
		2402	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2403	nice program for that purpose).
		2404
		2405	Then create a file with your private key (in PEM format, see
		2406	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2407	file should then look like this:
		2408
		2409	-----BEGIN RSA PRIVATE KEY-----
		2410	...header data
		2411	... lots of base64'y-stuff
		2412	-----END RSA PRIVATE KEY-----
		2413
		2414	-----BEGIN CERTIFICATE-----
		2415	... lots of base64'y-stuff
		2416	-----END CERTIFICATE-----
		2417
		2418	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2419	specify this file as C<cert_file>:
		2420
		2421	tcp_server undef, $port, sub {
		2422	my ($fh) = @_;
		2423
		2424	my $handle = new AnyEvent::Handle
		2425	fh => $fh,
		2426	tls => "accept",
		2427	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2428	...
		2429
		2430	When you have intermediate CA certificates that your clients might not
		2431	know about, just append them to the C<cert_file>.
1559		2432
1560	=back	2433	=back
1561		2434
1562		2435
1563	=head1 SUBCLASSING AnyEvent::Handle	2436	=head1 SUBCLASSING AnyEvent::Handle
…		…
1583		2456
1584	=item * all members not documented here and not prefixed with an underscore	2457	=item * all members not documented here and not prefixed with an underscore
1585	are free to use in subclasses.	2458	are free to use in subclasses.
1586		2459
1587	Of course, new versions of AnyEvent::Handle may introduce more "public"	2460	Of course, new versions of AnyEvent::Handle may introduce more "public"
1588	member variables, but thats just life, at least it is documented.	2461	member variables, but that's just life. At least it is documented.
1589		2462
1590	=back	2463	=back
1591		2464
1592	=head1 AUTHOR	2465	=head1 AUTHOR
1593		2466

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