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Revision 1.222 by root, Thu Aug 25 03:08:48 2011 UTC

1	package AnyEvent::Handle;
2
3	use Scalar::Util ();
4	use Carp ();
5	use Errno qw(EAGAIN EINTR);
6
7	use AnyEvent (); BEGIN { AnyEvent::common_sense }
8	use AnyEvent::Util qw(WSAEWOULDBLOCK);
9
10	=head1 NAME	1	=head1 NAME
11		2
12	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
13
14	=cut
15
16	our $VERSION = 4.86;
17		4
18	=head1 SYNOPSIS	5	=head1 SYNOPSIS
19		6
20	use AnyEvent;	7	use AnyEvent;
21	use AnyEvent::Handle;	8	use AnyEvent::Handle;
…		…
24		11
25	my $hdl; $hdl = new AnyEvent::Handle	12	my $hdl; $hdl = new AnyEvent::Handle
26	fh => \*STDIN,	13	fh => \*STDIN,
27	on_error => sub {	14	on_error => sub {
28	my ($hdl, $fatal, $msg) = @_;	15	my ($hdl, $fatal, $msg) = @_;
29	warn "got error $msg\n";	16	AE::log warn => "got error $msg\n";
30	$hdl->destroy;	17	$hdl->destroy;
31	$cv->send;	18	$cv->send;
32	);	19	};
33		20
34	# send some request line	21	# send some request line
35	$hdl->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
36		23
37	# read the response line	24	# read the response line
38	$hdl->push_read (line => sub {	25	$hdl->push_read (line => sub {
39	my ($hdl, $line) = @_;	26	my ($hdl, $line) = @_;
40	warn "got line <$line>\n";	27	AE::log warn => "got line <$line>\n";
41	$cv->send;	28	$cv->send;
42	});	29	});
43		30
44	$cv->recv;	31	$cv->recv;
45		32
46	=head1 DESCRIPTION	33	=head1 DESCRIPTION
47		34
48	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
49	filehandles. For utility functions for doing non-blocking connects and accepts	36	stream-based filehandles (sockets, pipes, and other stream things).
50	on sockets see L<AnyEvent::Util>.
51		37
52	The L<AnyEvent::Intro> tutorial contains some well-documented	38	The L<AnyEvent::Intro> tutorial contains some well-documented
53	AnyEvent::Handle examples.	39	AnyEvent::Handle examples.
54		40
55	In the following, when the documentation refers to of "bytes" then this	41	In the following, where the documentation refers to "bytes", it means
56	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
57	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.
58		47
59	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
60	argument.	49	argument.
61		50
		51	=cut
		52
		53	package AnyEvent::Handle;
		54
		55	use Scalar::Util ();
		56	use List::Util ();
		57	use Carp ();
		58	use Errno qw(EAGAIN EINTR);
		59
		60	use AnyEvent (); BEGIN { AnyEvent::common_sense }
		61	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		62
		63	our $VERSION = $AnyEvent::VERSION;
		64
		65	sub _load_func($) {
		66	my $func = $_[0];
		67
		68	unless (defined &$func) {
		69	my $pkg = $func;
		70	do {
		71	$pkg =~ s/::[^:]+$//
		72	or return;
		73	eval "require $pkg";
		74	} until defined &$func;
		75	}
		76
		77	\&$func
		78	}
		79
		80	sub MAX_READ_SIZE() { 131072 }
		81
62	=head1 METHODS	82	=head1 METHODS
63		83
64	=over 4	84	=over 4
65		85
66	=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...	86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
67		87
68	The constructor supports these arguments (all as C<< key => value >> pairs).	88	The constructor supports these arguments (all as C<< key => value >> pairs).
69		89
70	=over 4	90	=over 4
71		91
72	=item fh => $filehandle [MANDATORY]	92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
73		93
74	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
75
76	NOTE: The filehandle will be set to non-blocking mode (using	95	NOTE: The filehandle will be set to non-blocking mode (using
77	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
78	that mode.	97	that mode.
		98
		99	=item connect => [$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
		116	=item on_prepare => $cb->($handle)
		117
		118	This (rarely used) callback is called before a new connection is
		119	attempted, but after the file handle has been created (you can access that
		120	file handle via C<< $handle->{fh} >>). It could be used to prepare the
		121	file handle with parameters required for the actual connect (as opposed to
		122	settings that can be changed when the connection is already established).
		123
		124	The return value of this callback should be the connect timeout value in
		125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
		126	default timeout is to be used).
		127
		128	=item on_connect => $cb->($handle, $host, $port, $retry->())
		129
		130	This callback is called when a connection has been successfully established.
		131
		132	The peer's numeric host and port (the socket peername) are passed as
		133	parameters, together with a retry callback.
		134
		135	If, for some reason, the handle is not acceptable, calling C<$retry>
		136	will continue with the next connection target (in case of multi-homed
		137	hosts or SRV records there can be multiple connection endpoints). At the
		138	time it is called the read and write queues, eof status, tls status and
		139	similar properties of the handle will have been reset.
		140
		141	In most cases, you should ignore the C<$retry> parameter.
		142
		143	=item on_connect_error => $cb->($handle, $message)
		144
		145	This callback is called when the connection could not be
		146	established. C<$!> will contain the relevant error code, and C<$message> a
		147	message describing it (usually the same as C<"$!">).
		148
		149	If this callback isn't specified, then C<on_error> will be called with a
		150	fatal error instead.
		151
		152	=back
		153
		154	=item on_error => $cb->($handle, $fatal, $message)
		155
		156	This is the error callback, which is called when, well, some error
		157	occured, such as not being able to resolve the hostname, failure to
		158	connect, or a read error.
		159
		160	Some errors are fatal (which is indicated by C<$fatal> being true). On
		161	fatal errors the handle object will be destroyed (by a call to C<< ->
		162	destroy >>) after invoking the error callback (which means you are free to
		163	examine the handle object). Examples of fatal errors are an EOF condition
		164	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		165	cases where the other side can close the connection at will, it is
		166	often easiest to not report C<EPIPE> errors in this callback.
		167
		168	AnyEvent::Handle tries to find an appropriate error code for you to check
		169	against, but in some cases (TLS errors), this does not work well. It is
		170	recommended to always output the C<$message> argument in human-readable
		171	error messages (it's usually the same as C<"$!">).
		172
		173	Non-fatal errors can be retried by returning, but it is recommended
		174	to simply ignore this parameter and instead abondon the handle object
		175	when this callback is invoked. Examples of non-fatal errors are timeouts
		176	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		177
		178	On entry to the callback, the value of C<$!> contains the operating
		179	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		180	C<EPROTO>).
		181
		182	While not mandatory, it is I<highly> recommended to set this callback, as
		183	you will not be notified of errors otherwise. The default just calls
		184	C<croak>.
		185
		186	=item on_read => $cb->($handle)
		187
		188	This sets the default read callback, which is called when data arrives
		189	and no read request is in the queue (unlike read queue callbacks, this
		190	callback will only be called when at least one octet of data is in the
		191	read buffer).
		192
		193	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		194	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		195	must not enlarge or modify the read buffer, you can only remove data at
		196	the beginning from it.
		197
		198	You can also call C<< ->push_read (...) >> or any other function that
		199	modifies the read queue. Or do both. Or ...
		200
		201	When an EOF condition is detected, AnyEvent::Handle will first try to
		202	feed all the remaining data to the queued callbacks and C<on_read> before
		203	calling the C<on_eof> callback. If no progress can be made, then a fatal
		204	error will be raised (with C<$!> set to C<EPIPE>).
		205
		206	Note that, unlike requests in the read queue, an C<on_read> callback
		207	doesn't mean you I<require> some data: if there is an EOF and there
		208	are outstanding read requests then an error will be flagged. With an
		209	C<on_read> callback, the C<on_eof> callback will be invoked.
79		210
80	=item on_eof => $cb->($handle)	211	=item on_eof => $cb->($handle)
81		212
82	Set the callback to be called when an end-of-file condition is detected,	213	Set the callback to be called when an end-of-file condition is detected,
83	i.e. in the case of a socket, when the other side has closed the	214	i.e. in the case of a socket, when the other side has closed the
…		…
91	down.	222	down.
92		223
93	If an EOF condition has been detected but no C<on_eof> callback has been	224	If an EOF condition has been detected but no C<on_eof> callback has been
94	set, then a fatal error will be raised with C<$!> set to <0>.	225	set, then a fatal error will be raised with C<$!> set to <0>.
95		226
96	=item on_error => $cb->($handle, $fatal, $message)
97
98	This is the error callback, which is called when, well, some error
99	occured, such as not being able to resolve the hostname, failure to
100	connect or a read error.
101
102	Some errors are fatal (which is indicated by C<$fatal> being true). On
103	fatal errors the handle object will be destroyed (by a call to C<< ->
104	destroy >>) after invoking the error callback (which means you are free to
105	examine the handle object). Examples of fatal errors are an EOF condition
106	with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors.
107
108	AnyEvent::Handle tries to find an appropriate error code for you to check
109	against, but in some cases (TLS errors), this does not work well. It is
110	recommended to always output the C<$message> argument in human-readable
111	error messages (it's usually the same as C<"$!">).
112
113	Non-fatal errors can be retried by simply returning, but it is recommended
114	to simply ignore this parameter and instead abondon the handle object
115	when this callback is invoked. Examples of non-fatal errors are timeouts
116	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
117
118	On callback entrance, the value of C<$!> contains the operating system
119	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
120	C<EPROTO>).
121
122	While not mandatory, it is I<highly> recommended to set this callback, as
123	you will not be notified of errors otherwise. The default simply calls
124	C<croak>.
125
126	=item on_read => $cb->($handle)
127
128	This sets the default read callback, which is called when data arrives
129	and no read request is in the queue (unlike read queue callbacks, this
130	callback will only be called when at least one octet of data is in the
131	read buffer).
132
133	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
134	method or access the C<< $handle->{rbuf} >> member directly. Note that you
135	must not enlarge or modify the read buffer, you can only remove data at
136	the beginning from it.
137
138	When an EOF condition is detected then AnyEvent::Handle will first try to
139	feed all the remaining data to the queued callbacks and C<on_read> before
140	calling the C<on_eof> callback. If no progress can be made, then a fatal
141	error will be raised (with C<$!> set to C<EPIPE>).
142
143	Note that, unlike requests in the read queue, an C<on_read> callback
144	doesn't mean you I<require> some data: if there is an EOF and there
145	are outstanding read requests then an error will be flagged. With an
146	C<on_read> callback, the C<on_eof> callback will be invoked.
147
148	=item on_drain => $cb->($handle)	227	=item on_drain => $cb->($handle)
149		228
150	This sets the callback that is called when the write buffer becomes empty	229	This sets the callback that is called when the write buffer becomes empty
151	(or when the callback is set and the buffer is empty already).	230	(or immediately if the buffer is empty already).
152		231
153	To append to the write buffer, use the C<< ->push_write >> method.	232	To append to the write buffer, use the C<< ->push_write >> method.
154		233
155	This callback is useful when you don't want to put all of your write data	234	This callback is useful when you don't want to put all of your write data
156	into the queue at once, for example, when you want to write the contents	235	into the queue at once, for example, when you want to write the contents
…		…
158	memory and push it into the queue, but instead only read more data from	237	memory and push it into the queue, but instead only read more data from
159	the file when the write queue becomes empty.	238	the file when the write queue becomes empty.
160		239
161	=item timeout => $fractional_seconds	240	=item timeout => $fractional_seconds
162		241
		242	=item rtimeout => $fractional_seconds
		243
		244	=item wtimeout => $fractional_seconds
		245
163	If non-zero, then this enables an "inactivity" timeout: whenever this many	246	If non-zero, then these enables an "inactivity" timeout: whenever this
164	seconds pass without a successful read or write on the underlying file	247	many seconds pass without a successful read or write on the underlying
165	handle, the C<on_timeout> callback will be invoked (and if that one is	248	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
166	missing, a non-fatal C<ETIMEDOUT> error will be raised).	249	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		250	error will be raised).
167		251
		252	There are three variants of the timeouts that work independently of each
		253	other, for both read and write (triggered when nothing was read I<OR>
		254	written), just read (triggered when nothing was read), and just write:
		255	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		256	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		257	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		258
168	Note that timeout processing is also active when you currently do not have	259	Note that timeout processing is active even when you do not have any
169	any outstanding read or write requests: If you plan to keep the connection	260	outstanding read or write requests: If you plan to keep the connection
170	idle then you should disable the timout temporarily or ignore the timeout	261	idle then you should disable the timeout temporarily or ignore the
171	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply	262	timeout in the corresponding C<on_timeout> callback, in which case
172	restart the timeout.	263	AnyEvent::Handle will simply restart the timeout.
173		264
174	Zero (the default) disables this timeout.	265	Zero (the default) disables the corresponding timeout.
175		266
176	=item on_timeout => $cb->($handle)	267	=item on_timeout => $cb->($handle)
		268
		269	=item on_rtimeout => $cb->($handle)
		270
		271	=item on_wtimeout => $cb->($handle)
177		272
178	Called whenever the inactivity timeout passes. If you return from this	273	Called whenever the inactivity timeout passes. If you return from this
179	callback, then the timeout will be reset as if some activity had happened,	274	callback, then the timeout will be reset as if some activity had happened,
180	so this condition is not fatal in any way.	275	so this condition is not fatal in any way.
181		276
…		…
189	be configured to accept only so-and-so much data that it cannot act on	284	be configured to accept only so-and-so much data that it cannot act on
190	(for example, when expecting a line, an attacker could send an unlimited	285	(for example, when expecting a line, an attacker could send an unlimited
191	amount of data without a callback ever being called as long as the line	286	amount of data without a callback ever being called as long as the line
192	isn't finished).	287	isn't finished).
193		288
		289	=item wbuf_max => <bytes>
		290
		291	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		292	when the write buffer ever (strictly) exceeds this size. This is useful to
		293	avoid some forms of denial-of-service attacks.
		294
		295	Although the units of this parameter is bytes, this is the I<raw> number
		296	of bytes not yet accepted by the kernel. This can make a difference when
		297	you e.g. use TLS, as TLS typically makes your write data larger (but it
		298	can also make it smaller due to compression).
		299
		300	As an example of when this limit is useful, take a chat server that sends
		301	chat messages to a client. If the client does not read those in a timely
		302	manner then the send buffer in the server would grow unbounded.
		303
194	=item autocork => <boolean>	304	=item autocork => <boolean>
195		305
196	When disabled (the default), then C<push_write> will try to immediately	306	When disabled (the default), C<push_write> will try to immediately
197	write the data to the handle, if possible. This avoids having to register	307	write the data to the handle if possible. This avoids having to register
198	a write watcher and wait for the next event loop iteration, but can	308	a write watcher and wait for the next event loop iteration, but can
199	be inefficient if you write multiple small chunks (on the wire, this	309	be inefficient if you write multiple small chunks (on the wire, this
200	disadvantage is usually avoided by your kernel's nagle algorithm, see	310	disadvantage is usually avoided by your kernel's nagle algorithm, see
201	C<no_delay>, but this option can save costly syscalls).	311	C<no_delay>, but this option can save costly syscalls).
202		312
203	When enabled, then writes will always be queued till the next event loop	313	When enabled, writes will always be queued till the next event loop
204	iteration. This is efficient when you do many small writes per iteration,	314	iteration. This is efficient when you do many small writes per iteration,
205	but less efficient when you do a single write only per iteration (or when	315	but less efficient when you do a single write only per iteration (or when
206	the write buffer often is full). It also increases write latency.	316	the write buffer often is full). It also increases write latency.
207		317
208	=item no_delay => <boolean>	318	=item no_delay => <boolean>
…		…
212	the Nagle algorithm, and usually it is beneficial.	322	the Nagle algorithm, and usually it is beneficial.
213		323
214	In some situations you want as low a delay as possible, which can be	324	In some situations you want as low a delay as possible, which can be
215	accomplishd by setting this option to a true value.	325	accomplishd by setting this option to a true value.
216		326
217	The default is your opertaing system's default behaviour (most likely	327	The default is your operating system's default behaviour (most likely
218	enabled), this option explicitly enables or disables it, if possible.	328	enabled). This option explicitly enables or disables it, if possible.
		329
		330	=item keepalive => <boolean>
		331
		332	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		333	normally, TCP connections have no time-out once established, so TCP
		334	connections, once established, can stay alive forever even when the other
		335	side has long gone. TCP keepalives are a cheap way to take down long-lived
		336	TCP connections when the other side becomes unreachable. While the default
		337	is OS-dependent, TCP keepalives usually kick in after around two hours,
		338	and, if the other side doesn't reply, take down the TCP connection some 10
		339	to 15 minutes later.
		340
		341	It is harmless to specify this option for file handles that do not support
		342	keepalives, and enabling it on connections that are potentially long-lived
		343	is usually a good idea.
		344
		345	=item oobinline => <boolean>
		346
		347	BSD majorly fucked up the implementation of TCP urgent data. The result
		348	is that almost no OS implements TCP according to the specs, and every OS
		349	implements it slightly differently.
		350
		351	If you want to handle TCP urgent data, then setting this flag (the default
		352	is enabled) gives you the most portable way of getting urgent data, by
		353	putting it into the stream.
		354
		355	Since BSD emulation of OOB data on top of TCP's urgent data can have
		356	security implications, AnyEvent::Handle sets this flag automatically
		357	unless explicitly specified. Note that setting this flag after
		358	establishing a connection I<may> be a bit too late (data loss could
		359	already have occured on BSD systems), but at least it will protect you
		360	from most attacks.
219		361
220	=item read_size => <bytes>	362	=item read_size => <bytes>
221		363
222	The default read block size (the amount of bytes this module will	364	The initial read block size, the number of bytes this module will try
223	try to read during each loop iteration, which affects memory	365	to read during each loop iteration. Each handle object will consume
224	requirements). Default: C<8192>.	366	at least this amount of memory for the read buffer as well, so when
		367	handling many connections watch out for memory requirements). See also
		368	C<max_read_size>. Default: C<2048>.
		369
		370	=item max_read_size => <bytes>
		371
		372	The maximum read buffer size used by the dynamic adjustment
		373	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		374	one go it will double C<read_size> up to the maximum given by this
		375	option. Default: C<131072> or C<read_size>, whichever is higher.
225		376
226	=item low_water_mark => <bytes>	377	=item low_water_mark => <bytes>
227		378
228	Sets the amount of bytes (default: C<0>) that make up an "empty" write	379	Sets the number of bytes (default: C<0>) that make up an "empty" write
229	buffer: If the write reaches this size or gets even samller it is	380	buffer: If the buffer reaches this size or gets even samller it is
230	considered empty.	381	considered empty.
231		382
232	Sometimes it can be beneficial (for performance reasons) to add data to	383	Sometimes it can be beneficial (for performance reasons) to add data to
233	the write buffer before it is fully drained, but this is a rare case, as	384	the write buffer before it is fully drained, but this is a rare case, as
234	the operating system kernel usually buffers data as well, so the default	385	the operating system kernel usually buffers data as well, so the default
235	is good in almost all cases.	386	is good in almost all cases.
236		387
237	=item linger => <seconds>	388	=item linger => <seconds>
238		389
239	If non-zero (default: C<3600>), then the destructor of the	390	If this is non-zero (default: C<3600>), the destructor of the
240	AnyEvent::Handle object will check whether there is still outstanding	391	AnyEvent::Handle object will check whether there is still outstanding
241	write data and will install a watcher that will write this data to the	392	write data and will install a watcher that will write this data to the
242	socket. No errors will be reported (this mostly matches how the operating	393	socket. No errors will be reported (this mostly matches how the operating
243	system treats outstanding data at socket close time).	394	system treats outstanding data at socket close time).
244		395
…		…
251	A string used to identify the remote site - usually the DNS hostname	402	A string used to identify the remote site - usually the DNS hostname
252	(I<not> IDN!) used to create the connection, rarely the IP address.	403	(I<not> IDN!) used to create the connection, rarely the IP address.
253		404
254	Apart from being useful in error messages, this string is also used in TLS	405	Apart from being useful in error messages, this string is also used in TLS
255	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This	406	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
256	verification will be skipped when C<peername> is not specified or	407	verification will be skipped when C<peername> is not specified or is
257	C<undef>.	408	C<undef>.
258		409
259	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	410	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
260		411
261	When this parameter is given, it enables TLS (SSL) mode, that means	412	When this parameter is given, it enables TLS (SSL) mode, that means
262	AnyEvent will start a TLS handshake as soon as the conenction has been	413	AnyEvent will start a TLS handshake as soon as the connection has been
263	established and will transparently encrypt/decrypt data afterwards.	414	established and will transparently encrypt/decrypt data afterwards.
264		415
265	All TLS protocol errors will be signalled as C<EPROTO>, with an	416	All TLS protocol errors will be signalled as C<EPROTO>, with an
266	appropriate error message.	417	appropriate error message.
267		418
…		…
287	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,	438	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
288	passing in the wrong integer will lead to certain crash. This most often	439	passing in the wrong integer will lead to certain crash. This most often
289	happens when one uses a stylish C<< tls => 1 >> and is surprised about the	440	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
290	segmentation fault.	441	segmentation fault.
291		442
292	See the C<< ->starttls >> method for when need to start TLS negotiation later.	443	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
293		444
294	=item tls_ctx => $anyevent_tls	445	=item tls_ctx => $anyevent_tls
295		446
296	Use the given C<AnyEvent::TLS> object to create the new TLS connection	447	Use the given C<AnyEvent::TLS> object to create the new TLS connection
297	(unless a connection object was specified directly). If this parameter is	448	(unless a connection object was specified directly). If this
298	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	449	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		450	C<AnyEvent::Handle::TLS_CTX>.
299		451
300	Instead of an object, you can also specify a hash reference with C<< key	452	Instead of an object, you can also specify a hash reference with C<< key
301	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a	453	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
302	new TLS context object.	454	new TLS context object.
303		455
…		…
312		464
313	TLS handshake failures will not cause C<on_error> to be invoked when this	465	TLS handshake failures will not cause C<on_error> to be invoked when this
314	callback is in effect, instead, the error message will be passed to C<on_starttls>.	466	callback is in effect, instead, the error message will be passed to C<on_starttls>.
315		467
316	Without this callback, handshake failures lead to C<on_error> being	468	Without this callback, handshake failures lead to C<on_error> being
317	called, as normal.	469	called as usual.
318		470
319	Note that you cannot call C<starttls> right again in this callback. If you	471	Note that you cannot just call C<starttls> again in this callback. If you
320	need to do that, start an zero-second timer instead whose callback can	472	need to do that, start an zero-second timer instead whose callback can
321	then call C<< ->starttls >> again.	473	then call C<< ->starttls >> again.
322		474
323	=item on_stoptls => $cb->($handle)	475	=item on_stoptls => $cb->($handle)
324		476
…		…
350		502
351	sub new {	503	sub new {
352	my $class = shift;	504	my $class = shift;
353	my $self = bless { @_ }, $class;	505	my $self = bless { @_ }, $class;
354		506
355	$self->{fh} or Carp::croak "mandatory argument fh is missing";	507	if ($self->{fh}) {
		508	$self->_start;
		509	return unless $self->{fh}; # could be gone by now
		510
		511	} elsif ($self->{connect}) {
		512	require AnyEvent::Socket;
		513
		514	$self->{peername} = $self->{connect}[0]
		515	unless exists $self->{peername};
		516
		517	$self->{_skip_drain_rbuf} = 1;
		518
		519	{
		520	Scalar::Util::weaken (my $self = $self);
		521
		522	$self->{_connect} =
		523	AnyEvent::Socket::tcp_connect (
		524	$self->{connect}[0],
		525	$self->{connect}[1],
		526	sub {
		527	my ($fh, $host, $port, $retry) = @_;
		528
		529	delete $self->{_connect}; # no longer needed
		530
		531	if ($fh) {
		532	$self->{fh} = $fh;
		533
		534	delete $self->{_skip_drain_rbuf};
		535	$self->_start;
		536
		537	$self->{on_connect}
		538	and $self->{on_connect}($self, $host, $port, sub {
		539	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		540	$self->{_skip_drain_rbuf} = 1;
		541	&$retry;
		542	});
		543
		544	} else {
		545	if ($self->{on_connect_error}) {
		546	$self->{on_connect_error}($self, "$!");
		547	$self->destroy if $self;
		548	} else {
		549	$self->_error ($!, 1);
		550	}
		551	}
		552	},
		553	sub {
		554	local $self->{fh} = $_[0];
		555
		556	$self->{on_prepare}
		557	? $self->{on_prepare}->($self)
		558	: ()
		559	}
		560	);
		561	}
		562
		563	} else {
		564	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		565	}
		566
		567	$self
		568	}
		569
		570	sub _start {
		571	my ($self) = @_;
		572
		573	# too many clueless people try to use udp and similar sockets
		574	# with AnyEvent::Handle, do them a favour.
		575	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		576	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		577	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
356		578
357	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	579	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
358		580
		581	$self->{_activity} =
		582	$self->{_ractivity} =
359	$self->{_activity} = AnyEvent->now;	583	$self->{_wactivity} = AE::now;
360	$self->_timeout;
361		584
		585	$self->{read_size} ||= 2048;
		586	$self->{max_read_size} = $self->{read_size}
		587	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		588
		589	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		590	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		591	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		592
362	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};	593	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		594	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
363		595
		596	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		597
364	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})	598	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
365	if $self->{tls};	599	if $self->{tls};
366		600
367	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	601	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
368		602
369	$self->start_read	603	$self->start_read
370	if $self->{on_read};	604	if $self->{on_read} || @{ $self->{_queue} };
371		605
372	$self->{fh} && $self	606	$self->_drain_wbuf;
373	}	607	}
374
375	#sub _shutdown {
376	# my ($self) = @_;
377	#
378	# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
379	# $self->{_eof} = 1; # tell starttls et. al to stop trying
380	#
381	# &_freetls;
382	#}
383		608
384	sub _error {	609	sub _error {
385	my ($self, $errno, $fatal, $message) = @_;	610	my ($self, $errno, $fatal, $message) = @_;
386		611
387	$! = $errno;	612	$! = $errno;
388	$message ||= "$!";	613	$message ||= "$!";
389		614
390	if ($self->{on_error}) {	615	if ($self->{on_error}) {
391	$self->{on_error}($self, $fatal, $message);	616	$self->{on_error}($self, $fatal, $message);
392	$self->destroy if $fatal;	617	$self->destroy if $fatal;
393	} elsif ($self->{fh}) {	618	} elsif ($self->{fh} || $self->{connect}) {
394	$self->destroy;	619	$self->destroy;
395	Carp::croak "AnyEvent::Handle uncaught error: $message";	620	Carp::croak "AnyEvent::Handle uncaught error: $message";
396	}	621	}
397	}	622	}
398		623
…		…
424	$_[0]{on_eof} = $_[1];	649	$_[0]{on_eof} = $_[1];
425	}	650	}
426		651
427	=item $handle->on_timeout ($cb)	652	=item $handle->on_timeout ($cb)
428		653
429	Replace the current C<on_timeout> callback, or disables the callback (but	654	=item $handle->on_rtimeout ($cb)
430	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
431	argument and method.
432		655
433	=cut	656	=item $handle->on_wtimeout ($cb)
434		657
435	sub on_timeout {	658	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
436	$_[0]{on_timeout} = $_[1];	659	callback, or disables the callback (but not the timeout) if C<$cb> =
437	}	660	C<undef>. See the C<timeout> constructor argument and method.
		661
		662	=cut
		663
		664	# see below
438		665
439	=item $handle->autocork ($boolean)	666	=item $handle->autocork ($boolean)
440		667
441	Enables or disables the current autocork behaviour (see C<autocork>	668	Enables or disables the current autocork behaviour (see C<autocork>
442	constructor argument). Changes will only take effect on the next write.	669	constructor argument). Changes will only take effect on the next write.
…		…
455	=cut	682	=cut
456		683
457	sub no_delay {	684	sub no_delay {
458	$_[0]{no_delay} = $_[1];	685	$_[0]{no_delay} = $_[1];
459		686
		687	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		688	if $_[0]{fh};
		689	}
		690
		691	=item $handle->keepalive ($boolean)
		692
		693	Enables or disables the C<keepalive> setting (see constructor argument of
		694	the same name for details).
		695
		696	=cut
		697
		698	sub keepalive {
		699	$_[0]{keepalive} = $_[1];
		700
460	eval {	701	eval {
461	local $SIG{__DIE__};	702	local $SIG{__DIE__};
462	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];	703	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		704	if $_[0]{fh};
		705	};
		706	}
		707
		708	=item $handle->oobinline ($boolean)
		709
		710	Enables or disables the C<oobinline> setting (see constructor argument of
		711	the same name for details).
		712
		713	=cut
		714
		715	sub oobinline {
		716	$_[0]{oobinline} = $_[1];
		717
		718	eval {
		719	local $SIG{__DIE__};
		720	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		721	if $_[0]{fh};
		722	};
		723	}
		724
		725	=item $handle->keepalive ($boolean)
		726
		727	Enables or disables the C<keepalive> setting (see constructor argument of
		728	the same name for details).
		729
		730	=cut
		731
		732	sub keepalive {
		733	$_[0]{keepalive} = $_[1];
		734
		735	eval {
		736	local $SIG{__DIE__};
		737	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		738	if $_[0]{fh};
463	};	739	};
464	}	740	}
465		741
466	=item $handle->on_starttls ($cb)	742	=item $handle->on_starttls ($cb)
467		743
…		…
477		753
478	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).	754	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
479		755
480	=cut	756	=cut
481		757
482	sub on_starttls {	758	sub on_stoptls {
483	$_[0]{on_stoptls} = $_[1];	759	$_[0]{on_stoptls} = $_[1];
484	}	760	}
485		761
		762	=item $handle->rbuf_max ($max_octets)
		763
		764	Configures the C<rbuf_max> setting (C<undef> disables it).
		765
		766	=item $handle->wbuf_max ($max_octets)
		767
		768	Configures the C<wbuf_max> setting (C<undef> disables it).
		769
		770	=cut
		771
		772	sub rbuf_max {
		773	$_[0]{rbuf_max} = $_[1];
		774	}
		775
		776	sub wbuf_max {
		777	$_[0]{wbuf_max} = $_[1];
		778	}
		779
486	#############################################################################	780	#############################################################################
487		781
488	=item $handle->timeout ($seconds)	782	=item $handle->timeout ($seconds)
489		783
		784	=item $handle->rtimeout ($seconds)
		785
		786	=item $handle->wtimeout ($seconds)
		787
490	Configures (or disables) the inactivity timeout.	788	Configures (or disables) the inactivity timeout.
491		789
492	=cut	790	The timeout will be checked instantly, so this method might destroy the
		791	handle before it returns.
493		792
494	sub timeout {	793	=item $handle->timeout_reset
		794
		795	=item $handle->rtimeout_reset
		796
		797	=item $handle->wtimeout_reset
		798
		799	Reset the activity timeout, as if data was received or sent.
		800
		801	These methods are cheap to call.
		802
		803	=cut
		804
		805	for my $dir ("", "r", "w") {
		806	my $timeout = "${dir}timeout";
		807	my $tw = "_${dir}tw";
		808	my $on_timeout = "on_${dir}timeout";
		809	my $activity = "_${dir}activity";
		810	my $cb;
		811
		812	*$on_timeout = sub {
		813	$_[0]{$on_timeout} = $_[1];
		814	};
		815
		816	*$timeout = sub {
495	my ($self, $timeout) = @_;	817	my ($self, $new_value) = @_;
496		818
		819	$new_value >= 0
		820	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		821
497	$self->{timeout} = $timeout;	822	$self->{$timeout} = $new_value;
498	$self->_timeout;	823	delete $self->{$tw}; &$cb;
499	}	824	};
500		825
		826	*{"${dir}timeout_reset"} = sub {
		827	$_[0]{$activity} = AE::now;
		828	};
		829
		830	# main workhorse:
501	# reset the timeout watcher, as neccessary	831	# reset the timeout watcher, as neccessary
502	# also check for time-outs	832	# also check for time-outs
503	sub _timeout {	833	$cb = sub {
504	my ($self) = @_;	834	my ($self) = @_;
505		835
506	if ($self->{timeout}) {	836	if ($self->{$timeout} && $self->{fh}) {
507	my $NOW = AnyEvent->now;	837	my $NOW = AE::now;
508		838
509	# when would the timeout trigger?	839	# when would the timeout trigger?
510	my $after = $self->{_activity} + $self->{timeout} - $NOW;	840	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
511		841
512	# now or in the past already?	842	# now or in the past already?
513	if ($after <= 0) {	843	if ($after <= 0) {
514	$self->{_activity} = $NOW;	844	$self->{$activity} = $NOW;
515		845
516	if ($self->{on_timeout}) {	846	if ($self->{$on_timeout}) {
517	$self->{on_timeout}($self);	847	$self->{$on_timeout}($self);
518	} else {	848	} else {
519	$self->_error (Errno::ETIMEDOUT);	849	$self->_error (Errno::ETIMEDOUT);
		850	}
		851
		852	# callback could have changed timeout value, optimise
		853	return unless $self->{$timeout};
		854
		855	# calculate new after
		856	$after = $self->{$timeout};
520	}	857	}
521		858
522	# callback could have changed timeout value, optimise	859	Scalar::Util::weaken $self;
523	return unless $self->{timeout};	860	return unless $self; # ->error could have destroyed $self
524		861
525	# calculate new after	862	$self->{$tw} ||= AE::timer $after, 0, sub {
526	$after = $self->{timeout};	863	delete $self->{$tw};
		864	$cb->($self);
		865	};
		866	} else {
		867	delete $self->{$tw};
527	}	868	}
528
529	Scalar::Util::weaken $self;
530	return unless $self; # ->error could have destroyed $self
531
532	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
533	delete $self->{_tw};
534	$self->_timeout;
535	});
536	} else {
537	delete $self->{_tw};
538	}	869	}
539	}	870	}
540		871
541	#############################################################################	872	#############################################################################
542		873
…		…
558	=item $handle->on_drain ($cb)	889	=item $handle->on_drain ($cb)
559		890
560	Sets the C<on_drain> callback or clears it (see the description of	891	Sets the C<on_drain> callback or clears it (see the description of
561	C<on_drain> in the constructor).	892	C<on_drain> in the constructor).
562		893
		894	This method may invoke callbacks (and therefore the handle might be
		895	destroyed after it returns).
		896
563	=cut	897	=cut
564		898
565	sub on_drain {	899	sub on_drain {
566	my ($self, $cb) = @_;	900	my ($self, $cb) = @_;
567		901
…		…
571	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});	905	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
572	}	906	}
573		907
574	=item $handle->push_write ($data)	908	=item $handle->push_write ($data)
575		909
576	Queues the given scalar to be written. You can push as much data as you	910	Queues the given scalar to be written. You can push as much data as
577	want (only limited by the available memory), as C<AnyEvent::Handle>	911	you want (only limited by the available memory and C<wbuf_max>), as
578	buffers it independently of the kernel.	912	C<AnyEvent::Handle> buffers it independently of the kernel.
		913
		914	This method may invoke callbacks (and therefore the handle might be
		915	destroyed after it returns).
579		916
580	=cut	917	=cut
581		918
582	sub _drain_wbuf {	919	sub _drain_wbuf {
583	my ($self) = @_;	920	my ($self) = @_;
…		…
590	my $len = syswrite $self->{fh}, $self->{wbuf};	927	my $len = syswrite $self->{fh}, $self->{wbuf};
591		928
592	if (defined $len) {	929	if (defined $len) {
593	substr $self->{wbuf}, 0, $len, "";	930	substr $self->{wbuf}, 0, $len, "";
594		931
595	$self->{_activity} = AnyEvent->now;	932	$self->{_activity} = $self->{_wactivity} = AE::now;
596		933
597	$self->{on_drain}($self)	934	$self->{on_drain}($self)
598	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})	935	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
599	&& $self->{on_drain};	936	&& $self->{on_drain};
600		937
…		…
606		943
607	# try to write data immediately	944	# try to write data immediately
608	$cb->() unless $self->{autocork};	945	$cb->() unless $self->{autocork};
609		946
610	# if still data left in wbuf, we need to poll	947	# if still data left in wbuf, we need to poll
611	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	948	$self->{_ww} = AE::io $self->{fh}, 1, $cb
612	if length $self->{wbuf};	949	if length $self->{wbuf};
		950
		951	if (
		952	defined $self->{wbuf_max}
		953	&& $self->{wbuf_max} < length $self->{wbuf}
		954	) {
		955	$self->_error (Errno::ENOSPC, 1), return;
		956	}
613	};	957	};
614	}	958	}
615		959
616	our %WH;	960	our %WH;
617		961
		962	# deprecated
618	sub register_write_type($$) {	963	sub register_write_type($$) {
619	$WH{$_[0]} = $_[1];	964	$WH{$_[0]} = $_[1];
620	}	965	}
621		966
622	sub push_write {	967	sub push_write {
623	my $self = shift;	968	my $self = shift;
624		969
625	if (@_ > 1) {	970	if (@_ > 1) {
626	my $type = shift;	971	my $type = shift;
627		972
		973	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
628	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	974	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
629	->($self, @_);	975	->($self, @_);
630	}	976	}
631		977
		978	# we downgrade here to avoid hard-to-track-down bugs,
		979	# and diagnose the problem earlier and better.
		980
632	if ($self->{tls}) {	981	if ($self->{tls}) {
633	$self->{_tls_wbuf} .= $_[0];	982	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
634		983	&_dotls ($self) if $self->{fh};
635	&_dotls ($self);
636	} else {	984	} else {
637	$self->{wbuf} .= $_[0];	985	utf8::downgrade $self->{wbuf} .= $_[0];
638	$self->_drain_wbuf;	986	$self->_drain_wbuf if $self->{fh};
639	}	987	}
640	}	988	}
641		989
642	=item $handle->push_write (type => @args)	990	=item $handle->push_write (type => @args)
643		991
644	Instead of formatting your data yourself, you can also let this module do	992	Instead of formatting your data yourself, you can also let this module
645	the job by specifying a type and type-specific arguments.	993	do the job by specifying a type and type-specific arguments. You
		994	can also specify the (fully qualified) name of a package, in which
		995	case AnyEvent tries to load the package and then expects to find the
		996	C<anyevent_write_type> function inside (see "custom write types", below).
646		997
647	Predefined types are (if you have ideas for additional types, feel free to	998	Predefined types are (if you have ideas for additional types, feel free to
648	drop by and tell us):	999	drop by and tell us):
649		1000
650	=over 4	1001	=over 4
…		…
707	Other languages could read single lines terminated by a newline and pass	1058	Other languages could read single lines terminated by a newline and pass
708	this line into their JSON decoder of choice.	1059	this line into their JSON decoder of choice.
709		1060
710	=cut	1061	=cut
711		1062
		1063	sub json_coder() {
		1064	eval { require JSON::XS; JSON::XS->new->utf8 }
		1065	|| do { require JSON; JSON->new->utf8 }
		1066	}
		1067
712	register_write_type json => sub {	1068	register_write_type json => sub {
713	my ($self, $ref) = @_;	1069	my ($self, $ref) = @_;
714		1070
715	require JSON;	1071	my $json = $self->{json} ||= json_coder;
716		1072
717	$self->{json} ? $self->{json}->encode ($ref)	1073	$json->encode ($ref)
718	: JSON::encode_json ($ref)
719	};	1074	};
720		1075
721	=item storable => $reference	1076	=item storable => $reference
722		1077
723	Freezes the given reference using L<Storable> and writes it to the	1078	Freezes the given reference using L<Storable> and writes it to the
…		…
741	before it was actually written. One way to do that is to replace your	1096	before it was actually written. One way to do that is to replace your
742	C<on_drain> handler by a callback that shuts down the socket (and set	1097	C<on_drain> handler by a callback that shuts down the socket (and set
743	C<low_water_mark> to C<0>). This method is a shorthand for just that, and	1098	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
744	replaces the C<on_drain> callback with:	1099	replaces the C<on_drain> callback with:
745		1100
746	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown	1101	sub { shutdown $_[0]{fh}, 1 }
747		1102
748	This simply shuts down the write side and signals an EOF condition to the	1103	This simply shuts down the write side and signals an EOF condition to the
749	the peer.	1104	the peer.
750		1105
751	You can rely on the normal read queue and C<on_eof> handling	1106	You can rely on the normal read queue and C<on_eof> handling
752	afterwards. This is the cleanest way to close a connection.	1107	afterwards. This is the cleanest way to close a connection.
753		1108
		1109	This method may invoke callbacks (and therefore the handle might be
		1110	destroyed after it returns).
		1111
754	=cut	1112	=cut
755		1113
756	sub push_shutdown {	1114	sub push_shutdown {
757	my ($self) = @_;	1115	my ($self) = @_;
758		1116
759	delete $self->{low_water_mark};	1117	delete $self->{low_water_mark};
760	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });	1118	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
761	}	1119	}
762		1120
763	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	1121	=item custom write types - Package::anyevent_write_type $handle, @args
764		1122
765	This function (not method) lets you add your own types to C<push_write>.	1123	Instead of one of the predefined types, you can also specify the name of
		1124	a package. AnyEvent will try to load the package and then expects to find
		1125	a function named C<anyevent_write_type> inside. If it isn't found, it
		1126	progressively tries to load the parent package until it either finds the
		1127	function (good) or runs out of packages (bad).
		1128
766	Whenever the given C<type> is used, C<push_write> will invoke the code	1129	Whenever the given C<type> is used, C<push_write> will the function with
767	reference with the handle object and the remaining arguments.	1130	the handle object and the remaining arguments.
768		1131
769	The code reference is supposed to return a single octet string that will	1132	The function is supposed to return a single octet string that will be
770	be appended to the write buffer.	1133	appended to the write buffer, so you cna mentally treat this function as a
		1134	"arguments to on-the-wire-format" converter.
771		1135
772	Note that this is a function, and all types registered this way will be	1136	Example: implement a custom write type C<join> that joins the remaining
773	global, so try to use unique names.	1137	arguments using the first one.
		1138
		1139	$handle->push_write (My::Type => " ", 1,2,3);
		1140
		1141	# uses the following package, which can be defined in the "My::Type" or in
		1142	# the "My" modules to be auto-loaded, or just about anywhere when the
		1143	# My::Type::anyevent_write_type is defined before invoking it.
		1144
		1145	package My::Type;
		1146
		1147	sub anyevent_write_type {
		1148	my ($handle, $delim, @args) = @_;
		1149
		1150	join $delim, @args
		1151	}
774		1152
775	=cut	1153	=cut
776		1154
777	#############################################################################	1155	#############################################################################
778		1156
…		…
787	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1165	ways, the "simple" way, using only C<on_read> and the "complex" way, using
788	a queue.	1166	a queue.
789		1167
790	In the simple case, you just install an C<on_read> callback and whenever	1168	In the simple case, you just install an C<on_read> callback and whenever
791	new data arrives, it will be called. You can then remove some data (if	1169	new data arrives, it will be called. You can then remove some data (if
792	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna	1170	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
793	leave the data there if you want to accumulate more (e.g. when only a	1171	leave the data there if you want to accumulate more (e.g. when only a
794	partial message has been received so far).	1172	partial message has been received so far), or change the read queue with
		1173	e.g. C<push_read>.
795		1174
796	In the more complex case, you want to queue multiple callbacks. In this	1175	In the more complex case, you want to queue multiple callbacks. In this
797	case, AnyEvent::Handle will call the first queued callback each time new	1176	case, AnyEvent::Handle will call the first queued callback each time new
798	data arrives (also the first time it is queued) and removes it when it has	1177	data arrives (also the first time it is queued) and remove it when it has
799	done its job (see C<push_read>, below).	1178	done its job (see C<push_read>, below).
800		1179
801	This way you can, for example, push three line-reads, followed by reading	1180	This way you can, for example, push three line-reads, followed by reading
802	a chunk of data, and AnyEvent::Handle will execute them in order.	1181	a chunk of data, and AnyEvent::Handle will execute them in order.
803		1182
…		…
860	=cut	1239	=cut
861		1240
862	sub _drain_rbuf {	1241	sub _drain_rbuf {
863	my ($self) = @_;	1242	my ($self) = @_;
864		1243
		1244	# avoid recursion
		1245	return if $self->{_skip_drain_rbuf};
865	local $self->{_in_drain} = 1;	1246	local $self->{_skip_drain_rbuf} = 1;
866
867	if (
868	defined $self->{rbuf_max}
869	&& $self->{rbuf_max} < length $self->{rbuf}
870	) {
871	$self->_error (Errno::ENOSPC, 1), return;
872	}
873		1247
874	while () {	1248	while () {
875	# we need to use a separate tls read buffer, as we must not receive data while	1249	# we need to use a separate tls read buffer, as we must not receive data while
876	# we are draining the buffer, and this can only happen with TLS.	1250	# we are draining the buffer, and this can only happen with TLS.
877	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};	1251	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1252	if exists $self->{_tls_rbuf};
878		1253
879	my $len = length $self->{rbuf};	1254	my $len = length $self->{rbuf};
880		1255
881	if (my $cb = shift @{ $self->{_queue} }) {	1256	if (my $cb = shift @{ $self->{_queue} }) {
882	unless ($cb->($self)) {	1257	unless ($cb->($self)) {
883	if ($self->{_eof}) {	1258	# no progress can be made
884	# no progress can be made (not enough data and no data forthcoming)	1259	# (not enough data and no data forthcoming)
885	$self->_error (Errno::EPIPE, 1), return;	1260	$self->_error (Errno::EPIPE, 1), return
886	}	1261	if $self->{_eof};
887		1262
888	unshift @{ $self->{_queue} }, $cb;	1263	unshift @{ $self->{_queue} }, $cb;
889	last;	1264	last;
890	}	1265	}
891	} elsif ($self->{on_read}) {	1266	} elsif ($self->{on_read}) {
…		…
911	last;	1286	last;
912	}	1287	}
913	}	1288	}
914		1289
915	if ($self->{_eof}) {	1290	if ($self->{_eof}) {
916	if ($self->{on_eof}) {	1291	$self->{on_eof}
917	$self->{on_eof}($self)	1292	? $self->{on_eof}($self)
918	} else {
919	$self->_error (0, 1, "Unexpected end-of-file");	1293	: $self->_error (0, 1, "Unexpected end-of-file");
920	}	1294
		1295	return;
		1296	}
		1297
		1298	if (
		1299	defined $self->{rbuf_max}
		1300	&& $self->{rbuf_max} < length $self->{rbuf}
		1301	) {
		1302	$self->_error (Errno::ENOSPC, 1), return;
921	}	1303	}
922		1304
923	# may need to restart read watcher	1305	# may need to restart read watcher
924	unless ($self->{_rw}) {	1306	unless ($self->{_rw}) {
925	$self->start_read	1307	$self->start_read
…		…
931		1313
932	This replaces the currently set C<on_read> callback, or clears it (when	1314	This replaces the currently set C<on_read> callback, or clears it (when
933	the new callback is C<undef>). See the description of C<on_read> in the	1315	the new callback is C<undef>). See the description of C<on_read> in the
934	constructor.	1316	constructor.
935		1317
		1318	This method may invoke callbacks (and therefore the handle might be
		1319	destroyed after it returns).
		1320
936	=cut	1321	=cut
937		1322
938	sub on_read {	1323	sub on_read {
939	my ($self, $cb) = @_;	1324	my ($self, $cb) = @_;
940		1325
941	$self->{on_read} = $cb;	1326	$self->{on_read} = $cb;
942	$self->_drain_rbuf if $cb && !$self->{_in_drain};	1327	$self->_drain_rbuf if $cb;
943	}	1328	}
944		1329
945	=item $handle->rbuf	1330	=item $handle->rbuf
946		1331
947	Returns the read buffer (as a modifiable lvalue).	1332	Returns the read buffer (as a modifiable lvalue). You can also access the
		1333	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1334	much faster, and no less clean).
948		1335
949	You can access the read buffer directly as the C<< ->{rbuf} >>	1336	The only operation allowed on the read buffer (apart from looking at it)
950	member, if you want. However, the only operation allowed on the	1337	is removing data from its beginning. Otherwise modifying or appending to
951	read buffer (apart from looking at it) is removing data from its	1338	it is not allowed and will lead to hard-to-track-down bugs.
952	beginning. Otherwise modifying or appending to it is not allowed and will
953	lead to hard-to-track-down bugs.
954		1339
955	NOTE: The read buffer should only be used or modified if the C<on_read>,	1340	NOTE: The read buffer should only be used or modified in the C<on_read>
956	C<push_read> or C<unshift_read> methods are used. The other read methods	1341	callback or when C<push_read> or C<unshift_read> are used with a single
957	automatically manage the read buffer.	1342	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1343	will manage the read buffer on their own.
958		1344
959	=cut	1345	=cut
960		1346
961	sub rbuf : lvalue {	1347	sub rbuf : lvalue {
962	$_[0]{rbuf}	1348	$_[0]{rbuf}
…		…
979		1365
980	If enough data was available, then the callback must remove all data it is	1366	If enough data was available, then the callback must remove all data it is
981	interested in (which can be none at all) and return a true value. After returning	1367	interested in (which can be none at all) and return a true value. After returning
982	true, it will be removed from the queue.	1368	true, it will be removed from the queue.
983		1369
		1370	These methods may invoke callbacks (and therefore the handle might be
		1371	destroyed after it returns).
		1372
984	=cut	1373	=cut
985		1374
986	our %RH;	1375	our %RH;
987		1376
988	sub register_read_type($$) {	1377	sub register_read_type($$) {
…		…
994	my $cb = pop;	1383	my $cb = pop;
995		1384
996	if (@_) {	1385	if (@_) {
997	my $type = shift;	1386	my $type = shift;
998		1387
		1388	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
999	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1389	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1000	->($self, $cb, @_);	1390	->($self, $cb, @_);
1001	}	1391	}
1002		1392
1003	push @{ $self->{_queue} }, $cb;	1393	push @{ $self->{_queue} }, $cb;
1004	$self->_drain_rbuf unless $self->{_in_drain};	1394	$self->_drain_rbuf;
1005	}	1395	}
1006		1396
1007	sub unshift_read {	1397	sub unshift_read {
1008	my $self = shift;	1398	my $self = shift;
1009	my $cb = pop;	1399	my $cb = pop;
1010		1400
1011	if (@_) {	1401	if (@_) {
1012	my $type = shift;	1402	my $type = shift;
1013		1403
		1404	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1014	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1405	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1015	->($self, $cb, @_);	1406	->($self, $cb, @_);
1016	}	1407	}
1017		1408
1018
1019	unshift @{ $self->{_queue} }, $cb;	1409	unshift @{ $self->{_queue} }, $cb;
1020	$self->_drain_rbuf unless $self->{_in_drain};	1410	$self->_drain_rbuf;
1021	}	1411	}
1022		1412
1023	=item $handle->push_read (type => @args, $cb)	1413	=item $handle->push_read (type => @args, $cb)
1024		1414
1025	=item $handle->unshift_read (type => @args, $cb)	1415	=item $handle->unshift_read (type => @args, $cb)
1026		1416
1027	Instead of providing a callback that parses the data itself you can chose	1417	Instead of providing a callback that parses the data itself you can chose
1028	between a number of predefined parsing formats, for chunks of data, lines	1418	between a number of predefined parsing formats, for chunks of data, lines
1029	etc.	1419	etc. You can also specify the (fully qualified) name of a package, in
		1420	which case AnyEvent tries to load the package and then expects to find the
		1421	C<anyevent_read_type> function inside (see "custom read types", below).
1030		1422
1031	Predefined types are (if you have ideas for additional types, feel free to	1423	Predefined types are (if you have ideas for additional types, feel free to
1032	drop by and tell us):	1424	drop by and tell us):
1033		1425
1034	=over 4	1426	=over 4
…		…
1040	data.	1432	data.
1041		1433
1042	Example: read 2 bytes.	1434	Example: read 2 bytes.
1043		1435
1044	$handle->push_read (chunk => 2, sub {	1436	$handle->push_read (chunk => 2, sub {
1045	warn "yay ", unpack "H*", $_[1];	1437	AE::log debug => "yay " . unpack "H*", $_[1];
1046	});	1438	});
1047		1439
1048	=cut	1440	=cut
1049		1441
1050	register_read_type chunk => sub {	1442	register_read_type chunk => sub {
…		…
1126	the receive buffer when neither C<$accept> nor C<$reject> match,	1518	the receive buffer when neither C<$accept> nor C<$reject> match,
1127	and everything preceding and including the match will be accepted	1519	and everything preceding and including the match will be accepted
1128	unconditionally. This is useful to skip large amounts of data that you	1520	unconditionally. This is useful to skip large amounts of data that you
1129	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1521	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1130	have to start matching from the beginning. This is purely an optimisation	1522	have to start matching from the beginning. This is purely an optimisation
1131	and is usually worth only when you expect more than a few kilobytes.	1523	and is usually worth it only when you expect more than a few kilobytes.
1132		1524
1133	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1525	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1134	expect the header to be very large (it isn't in practise, but...), we use	1526	expect the header to be very large (it isn't in practice, but...), we use
1135	a skip regex to skip initial portions. The skip regex is tricky in that	1527	a skip regex to skip initial portions. The skip regex is tricky in that
1136	it only accepts something not ending in either \015 or \012, as these are	1528	it only accepts something not ending in either \015 or \012, as these are
1137	required for the accept regex.	1529	required for the accept regex.
1138		1530
1139	$handle->push_read (regex =>	1531	$handle->push_read (regex =>
…		…
1152		1544
1153	sub {	1545	sub {
1154	# accept	1546	# accept
1155	if ($$rbuf =~ $accept) {	1547	if ($$rbuf =~ $accept) {
1156	$data .= substr $$rbuf, 0, $+[0], "";	1548	$data .= substr $$rbuf, 0, $+[0], "";
1157	$cb->($self, $data);	1549	$cb->($_[0], $data);
1158	return 1;	1550	return 1;
1159	}	1551	}
1160		1552
1161	# reject	1553	# reject
1162	if ($reject && $$rbuf =~ $reject) {	1554	if ($reject && $$rbuf =~ $reject) {
1163	$self->_error (Errno::EBADMSG);	1555	$_[0]->_error (Errno::EBADMSG);
1164	}	1556	}
1165		1557
1166	# skip	1558	# skip
1167	if ($skip && $$rbuf =~ $skip) {	1559	if ($skip && $$rbuf =~ $skip) {
1168	$data .= substr $$rbuf, 0, $+[0], "";	1560	$data .= substr $$rbuf, 0, $+[0], "";
…		…
1184	my ($self, $cb) = @_;	1576	my ($self, $cb) = @_;
1185		1577
1186	sub {	1578	sub {
1187	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1579	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1188	if ($_[0]{rbuf} =~ /[^0-9]/) {	1580	if ($_[0]{rbuf} =~ /[^0-9]/) {
1189	$self->_error (Errno::EBADMSG);	1581	$_[0]->_error (Errno::EBADMSG);
1190	}	1582	}
1191	return;	1583	return;
1192	}	1584	}
1193		1585
1194	my $len = $1;	1586	my $len = $1;
1195		1587
1196	$self->unshift_read (chunk => $len, sub {	1588	$_[0]->unshift_read (chunk => $len, sub {
1197	my $string = $_[1];	1589	my $string = $_[1];
1198	$_[0]->unshift_read (chunk => 1, sub {	1590	$_[0]->unshift_read (chunk => 1, sub {
1199	if ($_[1] eq ",") {	1591	if ($_[1] eq ",") {
1200	$cb->($_[0], $string);	1592	$cb->($_[0], $string);
1201	} else {	1593	} else {
1202	$self->_error (Errno::EBADMSG);	1594	$_[0]->_error (Errno::EBADMSG);
1203	}	1595	}
1204	});	1596	});
1205	});	1597	});
1206		1598
1207	1	1599	1
…		…
1274	=cut	1666	=cut
1275		1667
1276	register_read_type json => sub {	1668	register_read_type json => sub {
1277	my ($self, $cb) = @_;	1669	my ($self, $cb) = @_;
1278		1670
1279	my $json = $self->{json} ||=	1671	my $json = $self->{json} ||= json_coder;
1280	eval { require JSON::XS; JSON::XS->new->utf8 }
1281	|| do { require JSON; JSON->new->utf8 };
1282		1672
1283	my $data;	1673	my $data;
1284	my $rbuf = \$self->{rbuf};	1674	my $rbuf = \$self->{rbuf};
1285		1675
1286	sub {	1676	sub {
1287	my $ref = eval { $json->incr_parse ($self->{rbuf}) };	1677	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1288		1678
1289	if ($ref) {	1679	if ($ref) {
1290	$self->{rbuf} = $json->incr_text;	1680	$_[0]{rbuf} = $json->incr_text;
1291	$json->incr_text = "";	1681	$json->incr_text = "";
1292	$cb->($self, $ref);	1682	$cb->($_[0], $ref);
1293		1683
1294	1	1684	1
1295	} elsif ($@) {	1685	} elsif ($@) {
1296	# error case	1686	# error case
1297	$json->incr_skip;	1687	$json->incr_skip;
1298		1688
1299	$self->{rbuf} = $json->incr_text;	1689	$_[0]{rbuf} = $json->incr_text;
1300	$json->incr_text = "";	1690	$json->incr_text = "";
1301		1691
1302	$self->_error (Errno::EBADMSG);	1692	$_[0]->_error (Errno::EBADMSG);
1303		1693
1304	()	1694	()
1305	} else {	1695	} else {
1306	$self->{rbuf} = "";	1696	$_[0]{rbuf} = "";
1307		1697
1308	()	1698	()
1309	}	1699	}
1310	}	1700	}
1311	};	1701	};
…		…
1344	# read remaining chunk	1734	# read remaining chunk
1345	$_[0]->unshift_read (chunk => $len, sub {	1735	$_[0]->unshift_read (chunk => $len, sub {
1346	if (my $ref = eval { Storable::thaw ($_[1]) }) {	1736	if (my $ref = eval { Storable::thaw ($_[1]) }) {
1347	$cb->($_[0], $ref);	1737	$cb->($_[0], $ref);
1348	} else {	1738	} else {
1349	$self->_error (Errno::EBADMSG);	1739	$_[0]->_error (Errno::EBADMSG);
1350	}	1740	}
1351	});	1741	});
1352	}	1742	}
1353		1743
1354	1	1744	1
1355	}	1745	}
1356	};	1746	};
1357		1747
1358	=back	1748	=back
1359		1749
1360	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)	1750	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1361		1751
1362	This function (not method) lets you add your own types to C<push_read>.	1752	Instead of one of the predefined types, you can also specify the name
		1753	of a package. AnyEvent will try to load the package and then expects to
		1754	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1755	progressively tries to load the parent package until it either finds the
		1756	function (good) or runs out of packages (bad).
1363		1757
1364	Whenever the given C<type> is used, C<push_read> will invoke the code	1758	Whenever this type is used, C<push_read> will invoke the function with the
1365	reference with the handle object, the callback and the remaining	1759	handle object, the original callback and the remaining arguments.
1366	arguments.
1367		1760
1368	The code reference is supposed to return a callback (usually a closure)	1761	The function is supposed to return a callback (usually a closure) that
1369	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1762	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1763	mentally treat the function as a "configurable read type to read callback"
		1764	converter.
1370		1765
1371	It should invoke the passed callback when it is done reading (remember to	1766	It should invoke the original callback when it is done reading (remember
1372	pass C<$handle> as first argument as all other callbacks do that).	1767	to pass C<$handle> as first argument as all other callbacks do that,
		1768	although there is no strict requirement on this).
1373		1769
1374	Note that this is a function, and all types registered this way will be
1375	global, so try to use unique names.
1376
1377	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1770	For examples, see the source of this module (F<perldoc -m
1378	search for C<register_read_type>)).	1771	AnyEvent::Handle>, search for C<register_read_type>)).
1379		1772
1380	=item $handle->stop_read	1773	=item $handle->stop_read
1381		1774
1382	=item $handle->start_read	1775	=item $handle->start_read
1383		1776
…		…
1389	Note that AnyEvent::Handle will automatically C<start_read> for you when	1782	Note that AnyEvent::Handle will automatically C<start_read> for you when
1390	you change the C<on_read> callback or push/unshift a read callback, and it	1783	you change the C<on_read> callback or push/unshift a read callback, and it
1391	will automatically C<stop_read> for you when neither C<on_read> is set nor	1784	will automatically C<stop_read> for you when neither C<on_read> is set nor
1392	there are any read requests in the queue.	1785	there are any read requests in the queue.
1393		1786
1394	These methods will have no effect when in TLS mode (as TLS doesn't support	1787	In older versions of this module (<= 5.3), these methods had no effect,
1395	half-duplex connections).	1788	as TLS does not support half-duplex connections. In current versions they
		1789	work as expected, as this behaviour is required to avoid certain resource
		1790	attacks, where the program would be forced to read (and buffer) arbitrary
		1791	amounts of data before being able to send some data. The drawback is that
		1792	some readings of the the SSL/TLS specifications basically require this
		1793	attack to be working, as SSL/TLS implementations might stall sending data
		1794	during a rehandshake.
		1795
		1796	As a guideline, during the initial handshake, you should not stop reading,
		1797	and as a client, it might cause problems, depending on your applciation.
1396		1798
1397	=cut	1799	=cut
1398		1800
1399	sub stop_read {	1801	sub stop_read {
1400	my ($self) = @_;	1802	my ($self) = @_;
1401		1803
1402	delete $self->{_rw} unless $self->{tls};	1804	delete $self->{_rw};
1403	}	1805	}
1404		1806
1405	sub start_read {	1807	sub start_read {
1406	my ($self) = @_;	1808	my ($self) = @_;
1407		1809
1408	unless ($self->{_rw} || $self->{_eof}) {	1810	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1409	Scalar::Util::weaken $self;	1811	Scalar::Util::weaken $self;
1410		1812
1411	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1813	$self->{_rw} = AE::io $self->{fh}, 0, sub {
1412	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});	1814	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1413	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1815	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1414		1816
1415	if ($len > 0) {	1817	if ($len > 0) {
1416	$self->{_activity} = AnyEvent->now;	1818	$self->{_activity} = $self->{_ractivity} = AE::now;
1417		1819
1418	if ($self->{tls}) {	1820	if ($self->{tls}) {
1419	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);	1821	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1420		1822
1421	&_dotls ($self);	1823	&_dotls ($self);
1422	} else {	1824	} else {
1423	$self->_drain_rbuf unless $self->{_in_drain};	1825	$self->_drain_rbuf;
		1826	}
		1827
		1828	if ($len == $self->{read_size}) {
		1829	$self->{read_size} *= 2;
		1830	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1831	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1424	}	1832	}
1425		1833
1426	} elsif (defined $len) {	1834	} elsif (defined $len) {
1427	delete $self->{_rw};	1835	delete $self->{_rw};
1428	$self->{_eof} = 1;	1836	$self->{_eof} = 1;
1429	$self->_drain_rbuf unless $self->{_in_drain};	1837	$self->_drain_rbuf;
1430		1838
1431	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1839	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1432	return $self->_error ($!, 1);	1840	return $self->_error ($!, 1);
1433	}	1841	}
1434	});	1842	};
1435	}	1843	}
1436	}	1844	}
1437		1845
1438	our $ERROR_SYSCALL;	1846	our $ERROR_SYSCALL;
1439	our $ERROR_WANT_READ;	1847	our $ERROR_WANT_READ;
…		…
1494	$self->{_eof} = 1;	1902	$self->{_eof} = 1;
1495	}	1903	}
1496	}	1904	}
1497		1905
1498	$self->{_tls_rbuf} .= $tmp;	1906	$self->{_tls_rbuf} .= $tmp;
1499	$self->_drain_rbuf unless $self->{_in_drain};	1907	$self->_drain_rbuf;
1500	$self->{tls} or return; # tls session might have gone away in callback	1908	$self->{tls} or return; # tls session might have gone away in callback
1501	}	1909	}
1502		1910
1503	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);	1911	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1504	return $self->_tls_error ($tmp)	1912	return $self->_tls_error ($tmp)
…		…
1506	&& ($tmp != $ERROR_SYSCALL || $!);	1914	&& ($tmp != $ERROR_SYSCALL || $!);
1507		1915
1508	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1916	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1509	$self->{wbuf} .= $tmp;	1917	$self->{wbuf} .= $tmp;
1510	$self->_drain_wbuf;	1918	$self->_drain_wbuf;
		1919	$self->{tls} or return; # tls session might have gone away in callback
1511	}	1920	}
1512		1921
1513	$self->{_on_starttls}	1922	$self->{_on_starttls}
1514	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()	1923	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1515	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");	1924	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
…		…
1518	=item $handle->starttls ($tls[, $tls_ctx])	1927	=item $handle->starttls ($tls[, $tls_ctx])
1519		1928
1520	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1929	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1521	object is created, you can also do that at a later time by calling	1930	object is created, you can also do that at a later time by calling
1522	C<starttls>.	1931	C<starttls>.
		1932
		1933	Starting TLS is currently an asynchronous operation - when you push some
		1934	write data and then call C<< ->starttls >> then TLS negotiation will start
		1935	immediately, after which the queued write data is then sent.
1523		1936
1524	The first argument is the same as the C<tls> constructor argument (either	1937	The first argument is the same as the C<tls> constructor argument (either
1525	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1938	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1526		1939
1527	The second argument is the optional C<AnyEvent::TLS> object that is used	1940	The second argument is the optional C<AnyEvent::TLS> object that is used
…		…
1532	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS	1945	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1533	context in C<< $handle->{tls_ctx} >> after this call and can be used or	1946	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1534	changed to your liking. Note that the handshake might have already started	1947	changed to your liking. Note that the handshake might have already started
1535	when this function returns.	1948	when this function returns.
1536		1949
1537	If it an error to start a TLS handshake more than once per	1950	Due to bugs in OpenSSL, it might or might not be possible to do multiple
1538	AnyEvent::Handle object (this is due to bugs in OpenSSL).	1951	handshakes on the same stream. It is best to not attempt to use the
		1952	stream after stopping TLS.
		1953
		1954	This method may invoke callbacks (and therefore the handle might be
		1955	destroyed after it returns).
1539		1956
1540	=cut	1957	=cut
1541		1958
1542	our %TLS_CACHE; #TODO not yet documented, should we?	1959	our %TLS_CACHE; #TODO not yet documented, should we?
1543		1960
1544	sub starttls {	1961	sub starttls {
1545	my ($self, $ssl, $ctx) = @_;	1962	my ($self, $tls, $ctx) = @_;
		1963
		1964	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1965	if $self->{tls};
		1966
		1967	$self->{tls} = $tls;
		1968	$self->{tls_ctx} = $ctx if @_ > 2;
		1969
		1970	return unless $self->{fh};
1546		1971
1547	require Net::SSLeay;	1972	require Net::SSLeay;
1548
1549	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1550	if $self->{tls};
1551		1973
1552	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();	1974	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1553	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();	1975	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1554		1976
		1977	$tls = delete $self->{tls};
1555	$ctx ||= $self->{tls_ctx};	1978	$ctx = $self->{tls_ctx};
		1979
		1980	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1556		1981
1557	if ("HASH" eq ref $ctx) {	1982	if ("HASH" eq ref $ctx) {
1558	require AnyEvent::TLS;	1983	require AnyEvent::TLS;
1559
1560	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
1561		1984
1562	if ($ctx->{cache}) {	1985	if ($ctx->{cache}) {
1563	my $key = $ctx+0;	1986	my $key = $ctx+0;
1564	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;	1987	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1565	} else {	1988	} else {
1566	$ctx = new AnyEvent::TLS %$ctx;	1989	$ctx = new AnyEvent::TLS %$ctx;
1567	}	1990	}
1568	}	1991	}
1569		1992
1570	$self->{tls_ctx} = $ctx || TLS_CTX ();	1993	$self->{tls_ctx} = $ctx || TLS_CTX ();
1571	$self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});	1994	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1572		1995
1573	# basically, this is deep magic (because SSL_read should have the same issues)	1996	# basically, this is deep magic (because SSL_read should have the same issues)
1574	# but the openssl maintainers basically said: "trust us, it just works".	1997	# but the openssl maintainers basically said: "trust us, it just works".
1575	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1998	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1576	# and mismaintained ssleay-module doesn't even offer them).	1999	# and mismaintained ssleay-module doesn't even offer them).
…		…
1583	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to	2006	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1584	# have identity issues in that area.	2007	# have identity issues in that area.
1585	# Net::SSLeay::CTX_set_mode ($ssl,	2008	# Net::SSLeay::CTX_set_mode ($ssl,
1586	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	2009	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1587	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	2010	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1588	Net::SSLeay::CTX_set_mode ($ssl, 1|2);	2011	Net::SSLeay::CTX_set_mode ($tls, 1|2);
1589		2012
1590	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2013	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1591	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2014	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1592		2015
		2016	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2017	$self->{rbuf} = "";
		2018
1593	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	2019	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1594		2020
1595	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }	2021	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1596	if $self->{on_starttls};	2022	if $self->{on_starttls};
1597		2023
1598	&_dotls; # need to trigger the initial handshake	2024	&_dotls; # need to trigger the initial handshake
…		…
1601		2027
1602	=item $handle->stoptls	2028	=item $handle->stoptls
1603		2029
1604	Shuts down the SSL connection - this makes a proper EOF handshake by	2030	Shuts down the SSL connection - this makes a proper EOF handshake by
1605	sending a close notify to the other side, but since OpenSSL doesn't	2031	sending a close notify to the other side, but since OpenSSL doesn't
1606	support non-blocking shut downs, it is not possible to re-use the stream	2032	support non-blocking shut downs, it is not guaranteed that you can re-use
1607	afterwards.	2033	the stream afterwards.
		2034
		2035	This method may invoke callbacks (and therefore the handle might be
		2036	destroyed after it returns).
1608		2037
1609	=cut	2038	=cut
1610		2039
1611	sub stoptls {	2040	sub stoptls {
1612	my ($self) = @_;	2041	my ($self) = @_;
1613		2042
1614	if ($self->{tls}) {	2043	if ($self->{tls} && $self->{fh}) {
1615	Net::SSLeay::shutdown ($self->{tls});	2044	Net::SSLeay::shutdown ($self->{tls});
1616		2045
1617	&_dotls;	2046	&_dotls;
1618		2047
1619	# # we don't give a shit. no, we do, but we can't. no...#d#	2048	# # we don't give a shit. no, we do, but we can't. no...#d#
…		…
1625	sub _freetls {	2054	sub _freetls {
1626	my ($self) = @_;	2055	my ($self) = @_;
1627		2056
1628	return unless $self->{tls};	2057	return unless $self->{tls};
1629		2058
1630	$self->{tls_ctx}->_put_session (delete $self->{tls});	2059	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2060	if $self->{tls} > 0;
1631		2061
1632	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};	2062	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1633	}	2063	}
		2064
		2065	=item $handle->resettls
		2066
		2067	This rarely-used method simply resets and TLS state on the handle, usually
		2068	causing data loss.
		2069
		2070	One case where it may be useful is when you want to skip over the data in
		2071	the stream but you are not interested in interpreting it, so data loss is
		2072	no concern.
		2073
		2074	=cut
		2075
		2076	*resettls = \&_freetls;
1634		2077
1635	sub DESTROY {	2078	sub DESTROY {
1636	my ($self) = @_;	2079	my ($self) = @_;
1637		2080
1638	&_freetls;	2081	&_freetls;
…		…
1643	my $fh = delete $self->{fh};	2086	my $fh = delete $self->{fh};
1644	my $wbuf = delete $self->{wbuf};	2087	my $wbuf = delete $self->{wbuf};
1645		2088
1646	my @linger;	2089	my @linger;
1647		2090
1648	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {	2091	push @linger, AE::io $fh, 1, sub {
1649	my $len = syswrite $fh, $wbuf, length $wbuf;	2092	my $len = syswrite $fh, $wbuf, length $wbuf;
1650		2093
1651	if ($len > 0) {	2094	if ($len > 0) {
1652	substr $wbuf, 0, $len, "";	2095	substr $wbuf, 0, $len, "";
1653	} else {	2096	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1654	@linger = (); # end	2097	@linger = (); # end
1655	}	2098	}
1656	});	2099	};
1657	push @linger, AnyEvent->timer (after => $linger, cb => sub {	2100	push @linger, AE::timer $linger, 0, sub {
1658	@linger = ();	2101	@linger = ();
1659	});	2102	};
1660	}	2103	}
1661	}	2104	}
1662		2105
1663	=item $handle->destroy	2106	=item $handle->destroy
1664		2107
1665	Shuts down the handle object as much as possible - this call ensures that	2108	Shuts down the handle object as much as possible - this call ensures that
1666	no further callbacks will be invoked and as many resources as possible	2109	no further callbacks will be invoked and as many resources as possible
1667	will be freed. You must not call any methods on the object afterwards.	2110	will be freed. Any method you will call on the handle object after
		2111	destroying it in this way will be silently ignored (and it will return the
		2112	empty list).
1668		2113
1669	Normally, you can just "forget" any references to an AnyEvent::Handle	2114	Normally, you can just "forget" any references to an AnyEvent::Handle
1670	object and it will simply shut down. This works in fatal error and EOF	2115	object and it will simply shut down. This works in fatal error and EOF
1671	callbacks, as well as code outside. It does I<NOT> work in a read or write	2116	callbacks, as well as code outside. It does I<NOT> work in a read or write
1672	callback, so when you want to destroy the AnyEvent::Handle object from	2117	callback, so when you want to destroy the AnyEvent::Handle object from
…		…
1686	sub destroy {	2131	sub destroy {
1687	my ($self) = @_;	2132	my ($self) = @_;
1688		2133
1689	$self->DESTROY;	2134	$self->DESTROY;
1690	%$self = ();	2135	%$self = ();
		2136	bless $self, "AnyEvent::Handle::destroyed";
1691	}	2137	}
		2138
		2139	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2140	#nop
		2141	}
		2142
		2143	=item $handle->destroyed
		2144
		2145	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2146	->destroy >>, true otherwise.
		2147
		2148	Can be useful to decide whether the handle is still valid after some
		2149	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2150	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2151	can destroy the handle, so work can be avoided by checking sometimes:
		2152
		2153	$hdl->starttls ("accept");
		2154	return if $hdl->destroyed;
		2155	$hdl->push_write (...
		2156
		2157	Note that the call to C<push_write> will silently be ignored if the handle
		2158	has been destroyed, so often you can just ignore the possibility of the
		2159	handle being destroyed.
		2160
		2161	=cut
		2162
		2163	sub destroyed { 0 }
		2164	sub AnyEvent::Handle::destroyed::destroyed { 1 }
1692		2165
1693	=item AnyEvent::Handle::TLS_CTX	2166	=item AnyEvent::Handle::TLS_CTX
1694		2167
1695	This function creates and returns the AnyEvent::TLS object used by default	2168	This function creates and returns the AnyEvent::TLS object used by default
1696	for TLS mode.	2169	for TLS mode.
…		…
1724		2197
1725	It is only safe to "forget" the reference inside EOF or error callbacks,	2198	It is only safe to "forget" the reference inside EOF or error callbacks,
1726	from within all other callbacks, you need to explicitly call the C<<	2199	from within all other callbacks, you need to explicitly call the C<<
1727	->destroy >> method.	2200	->destroy >> method.
1728		2201
		2202	=item Why is my C<on_eof> callback never called?
		2203
		2204	Probably because your C<on_error> callback is being called instead: When
		2205	you have outstanding requests in your read queue, then an EOF is
		2206	considered an error as you clearly expected some data.
		2207
		2208	To avoid this, make sure you have an empty read queue whenever your handle
		2209	is supposed to be "idle" (i.e. connection closes are O.K.). You cna set
		2210	an C<on_read> handler that simply pushes the first read requests in the
		2211	queue.
		2212
		2213	See also the next question, which explains this in a bit more detail.
		2214
		2215	=item How can I serve requests in a loop?
		2216
		2217	Most protocols consist of some setup phase (authentication for example)
		2218	followed by a request handling phase, where the server waits for requests
		2219	and handles them, in a loop.
		2220
		2221	There are two important variants: The first (traditional, better) variant
		2222	handles requests until the server gets some QUIT command, causing it to
		2223	close the connection first (highly desirable for a busy TCP server). A
		2224	client dropping the connection is an error, which means this variant can
		2225	detect an unexpected detection close.
		2226
		2227	To handle this case, always make sure you have a on-empty read queue, by
		2228	pushing the "read request start" handler on it:
		2229
		2230	# we assume a request starts with a single line
		2231	my @start_request; @start_request = (line => sub {
		2232	my ($hdl, $line) = @_;
		2233
		2234	... handle request
		2235
		2236	# push next request read, possibly from a nested callback
		2237	$hdl->push_read (@start_request);
		2238	});
		2239
		2240	# auth done, now go into request handling loop
		2241	# now push the first @start_request
		2242	$hdl->push_read (@start_request);
		2243
		2244	By always having an outstanding C<push_read>, the handle always expects
		2245	some data and raises the C<EPIPE> error when the connction is dropped
		2246	unexpectedly.
		2247
		2248	The second variant is a protocol where the client can drop the connection
		2249	at any time. For TCP, this means that the server machine may run out of
		2250	sockets easier, and in general, it means you cnanot distinguish a protocl
		2251	failure/client crash from a normal connection close. Nevertheless, these
		2252	kinds of protocols are common (and sometimes even the best solution to the
		2253	problem).
		2254
		2255	Having an outstanding read request at all times is possible if you ignore
		2256	C<EPIPE> errors, but this doesn't help with when the client drops the
		2257	connection during a request, which would still be an error.
		2258
		2259	A better solution is to push the initial request read in an C<on_read>
		2260	callback. This avoids an error, as when the server doesn't expect data
		2261	(i.e. is idly waiting for the next request, an EOF will not raise an
		2262	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2263	and simpler:
		2264
		2265	# auth done, now go into request handling loop
		2266	$hdl->on_read (sub {
		2267	my ($hdl) = @_;
		2268
		2269	# called each time we receive data but the read queue is empty
		2270	# simply start read the request
		2271
		2272	$hdl->push_read (line => sub {
		2273	my ($hdl, $line) = @_;
		2274
		2275	... handle request
		2276
		2277	# do nothing special when the request has been handled, just
		2278	# let the request queue go empty.
		2279	});
		2280	});
		2281
1729	=item I get different callback invocations in TLS mode/Why can't I pause	2282	=item I get different callback invocations in TLS mode/Why can't I pause
1730	reading?	2283	reading?
1731		2284
1732	Unlike, say, TCP, TLS connections do not consist of two independent	2285	Unlike, say, TCP, TLS connections do not consist of two independent
1733	communication channels, one for each direction. Or put differently. The	2286	communication channels, one for each direction. Or put differently, the
1734	read and write directions are not independent of each other: you cannot	2287	read and write directions are not independent of each other: you cannot
1735	write data unless you are also prepared to read, and vice versa.	2288	write data unless you are also prepared to read, and vice versa.
1736		2289
1737	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>	2290	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1738	callback invocations when you are not expecting any read data - the reason	2291	callback invocations when you are not expecting any read data - the reason
1739	is that AnyEvent::Handle always reads in TLS mode.	2292	is that AnyEvent::Handle always reads in TLS mode.
1740		2293
1741	During the connection, you have to make sure that you always have a	2294	During the connection, you have to make sure that you always have a
1742	non-empty read-queue, or an C<on_read> watcher. At the end of the	2295	non-empty read-queue, or an C<on_read> watcher. At the end of the
…		…
1754	$handle->on_eof (undef);	2307	$handle->on_eof (undef);
1755	$handle->on_error (sub {	2308	$handle->on_error (sub {
1756	my $data = delete $_[0]{rbuf};	2309	my $data = delete $_[0]{rbuf};
1757	});	2310	});
1758		2311
		2312	Note that this example removes the C<rbuf> member from the handle object,
		2313	which is not normally allowed by the API. It is expressly permitted in
		2314	this case only, as the handle object needs to be destroyed afterwards.
		2315
1759	The reason to use C<on_error> is that TCP connections, due to latencies	2316	The reason to use C<on_error> is that TCP connections, due to latencies
1760	and packets loss, might get closed quite violently with an error, when in	2317	and packets loss, might get closed quite violently with an error, when in
1761	fact, all data has been received.	2318	fact all data has been received.
1762		2319
1763	It is usually better to use acknowledgements when transferring data,	2320	It is usually better to use acknowledgements when transferring data,
1764	to make sure the other side hasn't just died and you got the data	2321	to make sure the other side hasn't just died and you got the data
1765	intact. This is also one reason why so many internet protocols have an	2322	intact. This is also one reason why so many internet protocols have an
1766	explicit QUIT command.	2323	explicit QUIT command.
…		…
1773	C<low_water_mark> this will be called precisely when all data has been	2330	C<low_water_mark> this will be called precisely when all data has been
1774	written to the socket:	2331	written to the socket:
1775		2332
1776	$handle->push_write (...);	2333	$handle->push_write (...);
1777	$handle->on_drain (sub {	2334	$handle->on_drain (sub {
1778	warn "all data submitted to the kernel\n";	2335	AE::log debug => "all data submitted to the kernel\n";
1779	undef $handle;	2336	undef $handle;
1780	});	2337	});
1781		2338
1782	If you just want to queue some data and then signal EOF to the other side,	2339	If you just want to queue some data and then signal EOF to the other side,
1783	consider using C<< ->push_shutdown >> instead.	2340	consider using C<< ->push_shutdown >> instead.
1784		2341
1785	=item I want to contact a TLS/SSL server, I don't care about security.	2342	=item I want to contact a TLS/SSL server, I don't care about security.
1786		2343
1787	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,	2344	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1788	simply connect to it and then create the AnyEvent::Handle with the C<tls>	2345	connect to it and then create the AnyEvent::Handle with the C<tls>
1789	parameter:	2346	parameter:
1790		2347
1791	tcp_connect $host, $port, sub {	2348	tcp_connect $host, $port, sub {
1792	my ($fh) = @_;	2349	my ($fh) = @_;
1793		2350
…		…
1893		2450
1894	=item * all members not documented here and not prefixed with an underscore	2451	=item * all members not documented here and not prefixed with an underscore
1895	are free to use in subclasses.	2452	are free to use in subclasses.
1896		2453
1897	Of course, new versions of AnyEvent::Handle may introduce more "public"	2454	Of course, new versions of AnyEvent::Handle may introduce more "public"
1898	member variables, but thats just life, at least it is documented.	2455	member variables, but that's just life. At least it is documented.
1899		2456
1900	=back	2457	=back
1901		2458
1902	=head1 AUTHOR	2459	=head1 AUTHOR
1903		2460

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