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Revision 1.205 by root, Mon Nov 15 17:11:00 2010 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict;
5
6	use AnyEvent ();
7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();
9	use Carp ();
10	use Fcntl ();
11	use Errno qw(EAGAIN EINTR);
12
13	=head1 NAME	1	=head1 NAME
14		2
15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17	=cut
18
19	our $VERSION = '0.04';
20		4
21	=head1 SYNOPSIS	5	=head1 SYNOPSIS
22		6
23	use AnyEvent;	7	use AnyEvent;
24	use AnyEvent::Handle;	8	use AnyEvent::Handle;
25		9
26	my $cv = AnyEvent->condvar;	10	my $cv = AnyEvent->condvar;
27		11
28	my $handle =	12	my $hdl; $hdl = new AnyEvent::Handle
29	AnyEvent::Handle->new (
30	fh => \*STDIN,	13	fh => \*STDIN,
31	on_eof => sub {	14	on_error => sub {
32	$cv->broadcast;	15	my ($hdl, $fatal, $msg) = @_;
33	},	16	warn "got error $msg\n";
		17	$hdl->destroy;
		18	$cv->send;
34	);	19	};
35		20
36	# send some request line	21	# send some request line
37	$handle->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
38		23
39	# read the response line	24	# read the response line
40	$handle->push_read (line => sub {	25	$hdl->push_read (line => sub {
41	my ($handle, $line) = @_;	26	my ($hdl, $line) = @_;
42	warn "read line <$line>\n";	27	warn "got line <$line>\n";
43	$cv->send;	28	$cv->send;
44	});	29	});
45		30
46	$cv->recv;	31	$cv->recv;
47		32
48	=head1 DESCRIPTION	33	=head1 DESCRIPTION
49		34
50	This module is a helper module to make it easier to do event-based I/O on	35	This is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	36	stream-based filehandles (sockets, pipes, and other stream things).
52	on sockets see L<AnyEvent::Util>.
53		37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
		40
54	In the following, when the documentation refers to of "bytes" then this	41	In the following, where the documentation refers to "bytes", it means
55	means characters. As sysread and syswrite are used for all I/O, their	42	characters. As sysread and syswrite are used for all I/O, their
56	treatment of characters applies to this module as well.	43	treatment of characters applies to this module as well.
		44
		45	At the very minimum, you should specify C<fh> or C<connect>, and the
		46	C<on_error> callback.
57		47
58	All callbacks will be invoked with the handle object as their first	48	All callbacks will be invoked with the handle object as their first
59	argument.	49	argument.
60		50
		51	=cut
		52
		53	package AnyEvent::Handle;
		54
		55	use Scalar::Util ();
		56	use List::Util ();
		57	use Carp ();
		58	use Errno qw(EAGAIN EINTR);
		59
		60	use AnyEvent (); BEGIN { AnyEvent::common_sense }
		61	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		62
		63	our $VERSION = $AnyEvent::VERSION;
		64
		65	sub _load_func($) {
		66	my $func = $_[0];
		67
		68	unless (defined &$func) {
		69	my $pkg = $func;
		70	do {
		71	$pkg =~ s/::[^:]+$//
		72	or return;
		73	eval "require $pkg";
		74	} until defined &$func;
		75	}
		76
		77	\&$func
		78	}
		79
		80	sub MAX_READ_SIZE() { 131072 }
		81
61	=head1 METHODS	82	=head1 METHODS
62		83
63	=over 4	84	=over 4
64		85
65	=item B<new (%args)>	86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
66		87
67	The constructor supports these arguments (all as key => value pairs).	88	The constructor supports these arguments (all as C<< key => value >> pairs).
68		89
69	=over 4	90	=over 4
70		91
71	=item fh => $filehandle [MANDATORY]	92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
72		93
73	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
74
75	NOTE: The filehandle will be set to non-blocking (using	95	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		97	that mode.
77		98
78	=item on_eof => $cb->($handle)	99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
79		100
80	Set the callback to be called on EOF.	101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
81		104
82	While not mandatory, it is highly recommended to set an eof callback,	105	You have to specify either this parameter, or C<fh>, above.
83	otherwise you might end up with a closed socket while you are still
84	waiting for data.
85		106
		107	It is possible to push requests on the read and write queues, and modify
		108	properties of the stream, even while AnyEvent::Handle is connecting.
		109
		110	When this parameter is specified, then the C<on_prepare>,
		111	C<on_connect_error> and C<on_connect> callbacks will be called under the
		112	appropriate circumstances:
		113
		114	=over 4
		115
86	=item on_error => $cb->($handle)	116	=item on_prepare => $cb->($handle)
87		117
		118	This (rarely used) callback is called before a new connection is
		119	attempted, but after the file handle has been created. It could be used to
		120	prepare the file handle with parameters required for the actual connect
		121	(as opposed to settings that can be changed when the connection is already
		122	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, $message)
		155
88	This is the fatal error callback, that is called when, well, a fatal error	156	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	157	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	158	connect, or a read error.
91		159
92	The object will not be in a usable state when this callback has been	160	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	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.
94		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
95	On callback entrance, the value of C<$!> contains the operating system	178	On entry to the callback, the value of C<$!> contains the operating
96	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).	179	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
97		180	C<EPROTO>).
98	The callback should throw an exception. If it returns, then
99	AnyEvent::Handle will C<croak> for you.
100		181
101	While not mandatory, it is I<highly> recommended to set this callback, as	182	While not mandatory, it is I<highly> recommended to set this callback, as
102	you will not be notified of errors otherwise. The default simply calls	183	you will not be notified of errors otherwise. The default just calls
103	die.	184	C<croak>.
104		185
105	=item on_read => $cb->($handle)	186	=item on_read => $cb->($handle)
106		187
107	This sets the default read callback, which is called when data arrives	188	This sets the default read callback, which is called when data arrives
108	and no read request is in the queue.	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).
109		192
110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	193	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111	method or access the C<$handle->{rbuf}> member directly.	194	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		195	must not enlarge or modify the read buffer, you can only remove data at
		196	the beginning from it.
112		197
		198	You can also call C<< ->push_read (...) >> or any other function that
		199	modifies the read queue. Or do both. Or ...
		200
113	When an EOF condition is detected then AnyEvent::Handle will first try to	201	When an EOF condition is detected, AnyEvent::Handle will first try to
114	feed all the remaining data to the queued callbacks and C<on_read> before	202	feed all the remaining data to the queued callbacks and C<on_read> before
115	calling the C<on_eof> callback. If no progress can be made, then a fatal	203	calling the C<on_eof> callback. If no progress can be made, then a fatal
116	error will be raised (with C<$!> set to C<EPIPE>).	204	error will be raised (with C<$!> set to C<EPIPE>).
117		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.
		210
		211	=item on_eof => $cb->($handle)
		212
		213	Set the callback to be called when an end-of-file condition is detected,
		214	i.e. in the case of a socket, when the other side has closed the
		215	connection cleanly, and there are no outstanding read requests in the
		216	queue (if there are read requests, then an EOF counts as an unexpected
		217	connection close and will be flagged as an error).
		218
		219	For sockets, this just means that the other side has stopped sending data,
		220	you can still try to write data, and, in fact, one can return from the EOF
		221	callback and continue writing data, as only the read part has been shut
		222	down.
		223
		224	If an EOF condition has been detected but no C<on_eof> callback has been
		225	set, then a fatal error will be raised with C<$!> set to <0>.
		226
118	=item on_drain => $cb->($handle)	227	=item on_drain => $cb->($handle)
119		228
120	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
121	(or when the callback is set and the buffer is empty already).	230	(or immediately if the buffer is empty already).
122		231
123	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.
124		233
		234	This callback is useful when you don't want to put all of your write data
		235	into the queue at once, for example, when you want to write the contents
		236	of some file to the socket you might not want to read the whole file into
		237	memory and push it into the queue, but instead only read more data from
		238	the file when the write queue becomes empty.
		239
125	=item timeout => $fractional_seconds	240	=item timeout => $fractional_seconds
126		241
		242	=item rtimeout => $fractional_seconds
		243
		244	=item wtimeout => $fractional_seconds
		245
127	If non-zero, then this enables an "inactivity" timeout: whenever this many	246	If non-zero, then these enables an "inactivity" timeout: whenever this
128	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
129	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
130	missing, an 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).
131		251
		252	There are three variants of the timeouts that work independently
		253	of each other, for both read and write, just read, and just write:
		254	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		255	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		256	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		257
132	Note that timeout processing is also active when you currently do not have	258	Note that timeout processing is active even when you do not have
133	any outstanding read or write requests: If you plan to keep the connection	259	any outstanding read or write requests: If you plan to keep the connection
134	idle then you should disable the timout temporarily or ignore the timeout	260	idle then you should disable the timeout temporarily or ignore the timeout
135	in the C<on_timeout> callback.	261	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		262	restart the timeout.
136		263
137	Zero (the default) disables this timeout.	264	Zero (the default) disables this timeout.
138		265
139	=item on_timeout => $cb->($handle)	266	=item on_timeout => $cb->($handle)
140		267
…		…
144		271
145	=item rbuf_max => <bytes>	272	=item rbuf_max => <bytes>
146		273
147	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	274	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
148	when the read buffer ever (strictly) exceeds this size. This is useful to	275	when the read buffer ever (strictly) exceeds this size. This is useful to
149	avoid denial-of-service attacks.	276	avoid some forms of denial-of-service attacks.
150		277
151	For example, a server accepting connections from untrusted sources should	278	For example, a server accepting connections from untrusted sources should
152	be configured to accept only so-and-so much data that it cannot act on	279	be configured to accept only so-and-so much data that it cannot act on
153	(for example, when expecting a line, an attacker could send an unlimited	280	(for example, when expecting a line, an attacker could send an unlimited
154	amount of data without a callback ever being called as long as the line	281	amount of data without a callback ever being called as long as the line
155	isn't finished).	282	isn't finished).
156		283
		284	=item autocork => <boolean>
		285
		286	When disabled (the default), C<push_write> will try to immediately
		287	write the data to the handle if possible. This avoids having to register
		288	a write watcher and wait for the next event loop iteration, but can
		289	be inefficient if you write multiple small chunks (on the wire, this
		290	disadvantage is usually avoided by your kernel's nagle algorithm, see
		291	C<no_delay>, but this option can save costly syscalls).
		292
		293	When enabled, writes will always be queued till the next event loop
		294	iteration. This is efficient when you do many small writes per iteration,
		295	but less efficient when you do a single write only per iteration (or when
		296	the write buffer often is full). It also increases write latency.
		297
		298	=item no_delay => <boolean>
		299
		300	When doing small writes on sockets, your operating system kernel might
		301	wait a bit for more data before actually sending it out. This is called
		302	the Nagle algorithm, and usually it is beneficial.
		303
		304	In some situations you want as low a delay as possible, which can be
		305	accomplishd by setting this option to a true value.
		306
		307	The default is your operating system's default behaviour (most likely
		308	enabled). This option explicitly enables or disables it, if possible.
		309
		310	=item keepalive => <boolean>
		311
		312	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		313	normally, TCP connections have no time-out once established, so TCP
		314	connections, once established, can stay alive forever even when the other
		315	side has long gone. TCP keepalives are a cheap way to take down long-lived
		316	TCP connections when the other side becomes unreachable. While the default
		317	is OS-dependent, TCP keepalives usually kick in after around two hours,
		318	and, if the other side doesn't reply, take down the TCP connection some 10
		319	to 15 minutes later.
		320
		321	It is harmless to specify this option for file handles that do not support
		322	keepalives, and enabling it on connections that are potentially long-lived
		323	is usually a good idea.
		324
		325	=item oobinline => <boolean>
		326
		327	BSD majorly fucked up the implementation of TCP urgent data. The result
		328	is that almost no OS implements TCP according to the specs, and every OS
		329	implements it slightly differently.
		330
		331	If you want to handle TCP urgent data, then setting this flag (the default
		332	is enabled) gives you the most portable way of getting urgent data, by
		333	putting it into the stream.
		334
		335	Since BSD emulation of OOB data on top of TCP's urgent data can have
		336	security implications, AnyEvent::Handle sets this flag automatically
		337	unless explicitly specified. Note that setting this flag after
		338	establishing a connection I<may> be a bit too late (data loss could
		339	already have occured on BSD systems), but at least it will protect you
		340	from most attacks.
		341
157	=item read_size => <bytes>	342	=item read_size => <bytes>
158		343
159	The default read block size (the amount of bytes this module will try to read	344	The initial read block size, the number of bytes this module will try to
160	on each [loop iteration). Default: C<4096>.	345	read during each loop iteration. Each handle object will consume at least
		346	this amount of memory for the read buffer as well, so when handling many
		347	connections requirements). See also C<max_read_size>. Default: C<2048>.
		348
		349	=item max_read_size => <bytes>
		350
		351	The maximum read buffer size used by the dynamic adjustment
		352	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
		353	one go it will double C<read_size> up to the maximum given by this
		354	option. Default: C<131072> or C<read_size>, whichever is higher.
161		355
162	=item low_water_mark => <bytes>	356	=item low_water_mark => <bytes>
163		357
164	Sets the amount of bytes (default: C<0>) that make up an "empty" write	358	Sets the number of bytes (default: C<0>) that make up an "empty" write
165	buffer: If the write reaches this size or gets even samller it is	359	buffer: If the buffer reaches this size or gets even samller it is
166	considered empty.	360	considered empty.
167		361
		362	Sometimes it can be beneficial (for performance reasons) to add data to
		363	the write buffer before it is fully drained, but this is a rare case, as
		364	the operating system kernel usually buffers data as well, so the default
		365	is good in almost all cases.
		366
		367	=item linger => <seconds>
		368
		369	If this is non-zero (default: C<3600>), the destructor of the
		370	AnyEvent::Handle object will check whether there is still outstanding
		371	write data and will install a watcher that will write this data to the
		372	socket. No errors will be reported (this mostly matches how the operating
		373	system treats outstanding data at socket close time).
		374
		375	This will not work for partial TLS data that could not be encoded
		376	yet. This data will be lost. Calling the C<stoptls> method in time might
		377	help.
		378
		379	=item peername => $string
		380
		381	A string used to identify the remote site - usually the DNS hostname
		382	(I<not> IDN!) used to create the connection, rarely the IP address.
		383
		384	Apart from being useful in error messages, this string is also used in TLS
		385	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		386	verification will be skipped when C<peername> is not specified or is
		387	C<undef>.
		388
168	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	389	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
169		390
170	When this parameter is given, it enables TLS (SSL) mode, that means it	391	When this parameter is given, it enables TLS (SSL) mode, that means
171	will start making tls handshake and will transparently encrypt/decrypt	392	AnyEvent will start a TLS handshake as soon as the connection has been
172	data.	393	established and will transparently encrypt/decrypt data afterwards.
		394
		395	All TLS protocol errors will be signalled as C<EPROTO>, with an
		396	appropriate error message.
173		397
174	TLS mode requires Net::SSLeay to be installed (it will be loaded	398	TLS mode requires Net::SSLeay to be installed (it will be loaded
175	automatically when you try to create a TLS handle).	399	automatically when you try to create a TLS handle): this module doesn't
		400	have a dependency on that module, so if your module requires it, you have
		401	to add the dependency yourself.
176		402
177	For the TLS server side, use C<accept>, and for the TLS client side of a	403	Unlike TCP, TLS has a server and client side: for the TLS server side, use
178	connection, use C<connect> mode.	404	C<accept>, and for the TLS client side of a connection, use C<connect>
		405	mode.
179		406
180	You can also provide your own TLS connection object, but you have	407	You can also provide your own TLS connection object, but you have
181	to make sure that you call either C<Net::SSLeay::set_connect_state>	408	to make sure that you call either C<Net::SSLeay::set_connect_state>
182	or C<Net::SSLeay::set_accept_state> on it before you pass it to	409	or C<Net::SSLeay::set_accept_state> on it before you pass it to
183	AnyEvent::Handle.	410	AnyEvent::Handle. Also, this module will take ownership of this connection
		411	object.
184		412
		413	At some future point, AnyEvent::Handle might switch to another TLS
		414	implementation, then the option to use your own session object will go
		415	away.
		416
		417	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		418	passing in the wrong integer will lead to certain crash. This most often
		419	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		420	segmentation fault.
		421
185	See the C<starttls> method if you need to start TLs negotiation later.	422	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
186		423
187	=item tls_ctx => $ssl_ctx	424	=item tls_ctx => $anyevent_tls
188		425
189	Use the given Net::SSLeay::CTX object to create the new TLS connection	426	Use the given C<AnyEvent::TLS> object to create the new TLS connection
190	(unless a connection object was specified directly). If this parameter is	427	(unless a connection object was specified directly). If this parameter is
191	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	428	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
192		429
		430	Instead of an object, you can also specify a hash reference with C<< key
		431	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		432	new TLS context object.
		433
		434	=item on_starttls => $cb->($handle, $success[, $error_message])
		435
		436	This callback will be invoked when the TLS/SSL handshake has finished. If
		437	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		438	(C<on_stoptls> will not be called in this case).
		439
		440	The session in C<< $handle->{tls} >> can still be examined in this
		441	callback, even when the handshake was not successful.
		442
		443	TLS handshake failures will not cause C<on_error> to be invoked when this
		444	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		445
		446	Without this callback, handshake failures lead to C<on_error> being
		447	called as usual.
		448
		449	Note that you cannot just call C<starttls> again in this callback. If you
		450	need to do that, start an zero-second timer instead whose callback can
		451	then call C<< ->starttls >> again.
		452
		453	=item on_stoptls => $cb->($handle)
		454
		455	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		456	set, then it will be invoked after freeing the TLS session. If it is not,
		457	then a TLS shutdown condition will be treated like a normal EOF condition
		458	on the handle.
		459
		460	The session in C<< $handle->{tls} >> can still be examined in this
		461	callback.
		462
		463	This callback will only be called on TLS shutdowns, not when the
		464	underlying handle signals EOF.
		465
193	=item json => JSON or JSON::XS object	466	=item json => JSON or JSON::XS object
194		467
195	This is the json coder object used by the C<json> read and write types.	468	This is the json coder object used by the C<json> read and write types.
196		469
197	If you don't supply it, then AnyEvent::Handle will create and use a	470	If you don't supply it, then AnyEvent::Handle will create and use a
198	suitable one, which will write and expect UTF-8 encoded JSON texts.	471	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		472	texts.
199		473
200	Note that you are responsible to depend on the JSON module if you want to	474	Note that you are responsible to depend on the JSON module if you want to
201	use this functionality, as AnyEvent does not have a dependency itself.	475	use this functionality, as AnyEvent does not have a dependency itself.
202		476
203	=item filter_r => $cb
204
205	=item filter_w => $cb
206
207	These exist, but are undocumented at this time.
208
209	=back	477	=back
210		478
211	=cut	479	=cut
212		480
213	sub new {	481	sub new {
214	my $class = shift;	482	my $class = shift;
215
216	my $self = bless { @_ }, $class;	483	my $self = bless { @_ }, $class;
217		484
218	$self->{fh} or Carp::croak "mandatory argument fh is missing";	485	if ($self->{fh}) {
		486	$self->_start;
		487	return unless $self->{fh}; # could be gone by now
		488
		489	} elsif ($self->{connect}) {
		490	require AnyEvent::Socket;
		491
		492	$self->{peername} = $self->{connect}[0]
		493	unless exists $self->{peername};
		494
		495	$self->{_skip_drain_rbuf} = 1;
		496
		497	{
		498	Scalar::Util::weaken (my $self = $self);
		499
		500	$self->{_connect} =
		501	AnyEvent::Socket::tcp_connect (
		502	$self->{connect}[0],
		503	$self->{connect}[1],
		504	sub {
		505	my ($fh, $host, $port, $retry) = @_;
		506
		507	delete $self->{_connect};
		508
		509	if ($fh) {
		510	$self->{fh} = $fh;
		511
		512	delete $self->{_skip_drain_rbuf};
		513	$self->_start;
		514
		515	$self->{on_connect}
		516	and $self->{on_connect}($self, $host, $port, sub {
		517	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		518	$self->{_skip_drain_rbuf} = 1;
		519	&$retry;
		520	});
		521
		522	} else {
		523	if ($self->{on_connect_error}) {
		524	$self->{on_connect_error}($self, "$!");
		525	$self->destroy;
		526	} else {
		527	$self->_error ($!, 1);
		528	}
		529	}
		530	},
		531	sub {
		532	local $self->{fh} = $_[0];
		533
		534	$self->{on_prepare}
		535	? $self->{on_prepare}->($self)
		536	: ()
		537	}
		538	);
		539	}
		540
		541	} else {
		542	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		543	}
		544
		545	$self
		546	}
		547
		548	sub _start {
		549	my ($self) = @_;
		550
		551	# too many clueless people try to use udp and similar sockets
		552	# with AnyEvent::Handle, do them a favour.
		553	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		554	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		555	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
219		556
220	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	557	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
221		558
222	if ($self->{tls}) {	559	$self->{_activity} =
223	require Net::SSLeay;	560	$self->{_ractivity} =
		561	$self->{_wactivity} = AE::now;
		562
		563	$self->{read_size} ||= 2048;
		564	$self->{max_read_size} = $self->{read_size}
		565	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		566
		567	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		568	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		569	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		570
		571	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		572	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		573
		574	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		575
224	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	576	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
225	}	577	if $self->{tls};
226		578
227	# $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; # nop
228	# $self->on_error (delete $self->{on_error}) if $self->{on_error}; # nop
229	# $self->on_read (delete $self->{on_read} ) if $self->{on_read}; # nop
230	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	579	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
231		580
232	$self->{_activity} = AnyEvent->now;
233	$self->_timeout;
234
235	$self->start_read;	581	$self->start_read
		582	if $self->{on_read} || @{ $self->{_queue} };
236		583
237	$self	584	$self->_drain_wbuf;
238	}	585	}
239		586
240	sub _shutdown {
241	my ($self) = @_;
242
243	delete $self->{_rw};
244	delete $self->{_ww};
245	delete $self->{fh};
246	}
247
248	sub error {	587	sub _error {
249	my ($self) = @_;	588	my ($self, $errno, $fatal, $message) = @_;
250		589
251	{	590	$! = $errno;
252	local $!;	591	$message ||= "$!";
253	$self->_shutdown;
254	}
255		592
256	$self->{on_error}($self)
257	if $self->{on_error};	593	if ($self->{on_error}) {
258		594	$self->{on_error}($self, $fatal, $message);
		595	$self->destroy if $fatal;
		596	} elsif ($self->{fh} || $self->{connect}) {
		597	$self->destroy;
259	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	598	Carp::croak "AnyEvent::Handle uncaught error: $message";
		599	}
260	}	600	}
261		601
262	=item $fh = $handle->fh	602	=item $fh = $handle->fh
263		603
264	This method returns the file handle of the L<AnyEvent::Handle> object.	604	This method returns the file handle used to create the L<AnyEvent::Handle> object.
265		605
266	=cut	606	=cut
267		607
268	sub fh { $_[0]{fh} }	608	sub fh { $_[0]{fh} }
269		609
…		…
287	$_[0]{on_eof} = $_[1];	627	$_[0]{on_eof} = $_[1];
288	}	628	}
289		629
290	=item $handle->on_timeout ($cb)	630	=item $handle->on_timeout ($cb)
291		631
292	Replace the current C<on_timeout> callback, or disables the callback	632	=item $handle->on_rtimeout ($cb)
293	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
294	argument.
295		633
296	=cut	634	=item $handle->on_wtimeout ($cb)
297		635
		636	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		637	callback, or disables the callback (but not the timeout) if C<$cb> =
		638	C<undef>. See the C<timeout> constructor argument and method.
		639
		640	=cut
		641
		642	# see below
		643
		644	=item $handle->autocork ($boolean)
		645
		646	Enables or disables the current autocork behaviour (see C<autocork>
		647	constructor argument). Changes will only take effect on the next write.
		648
		649	=cut
		650
		651	sub autocork {
		652	$_[0]{autocork} = $_[1];
		653	}
		654
		655	=item $handle->no_delay ($boolean)
		656
		657	Enables or disables the C<no_delay> setting (see constructor argument of
		658	the same name for details).
		659
		660	=cut
		661
		662	sub no_delay {
		663	$_[0]{no_delay} = $_[1];
		664
		665	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		666	if $_[0]{fh};
		667	}
		668
		669	=item $handle->keepalive ($boolean)
		670
		671	Enables or disables the C<keepalive> setting (see constructor argument of
		672	the same name for details).
		673
		674	=cut
		675
		676	sub keepalive {
		677	$_[0]{keepalive} = $_[1];
		678
		679	eval {
		680	local $SIG{__DIE__};
		681	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		682	if $_[0]{fh};
		683	};
		684	}
		685
		686	=item $handle->oobinline ($boolean)
		687
		688	Enables or disables the C<oobinline> setting (see constructor argument of
		689	the same name for details).
		690
		691	=cut
		692
		693	sub oobinline {
		694	$_[0]{oobinline} = $_[1];
		695
		696	eval {
		697	local $SIG{__DIE__};
		698	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		699	if $_[0]{fh};
		700	};
		701	}
		702
		703	=item $handle->keepalive ($boolean)
		704
		705	Enables or disables the C<keepalive> setting (see constructor argument of
		706	the same name for details).
		707
		708	=cut
		709
		710	sub keepalive {
		711	$_[0]{keepalive} = $_[1];
		712
		713	eval {
		714	local $SIG{__DIE__};
		715	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		716	if $_[0]{fh};
		717	};
		718	}
		719
		720	=item $handle->on_starttls ($cb)
		721
		722	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		723
		724	=cut
		725
		726	sub on_starttls {
		727	$_[0]{on_starttls} = $_[1];
		728	}
		729
		730	=item $handle->on_stoptls ($cb)
		731
		732	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		733
		734	=cut
		735
298	sub on_timeout {	736	sub on_stoptls {
299	$_[0]{on_timeout} = $_[1];	737	$_[0]{on_stoptls} = $_[1];
		738	}
		739
		740	=item $handle->rbuf_max ($max_octets)
		741
		742	Configures the C<rbuf_max> setting (C<undef> disables it).
		743
		744	=cut
		745
		746	sub rbuf_max {
		747	$_[0]{rbuf_max} = $_[1];
300	}	748	}
301		749
302	#############################################################################	750	#############################################################################
303		751
304	=item $handle->timeout ($seconds)	752	=item $handle->timeout ($seconds)
305		753
		754	=item $handle->rtimeout ($seconds)
		755
		756	=item $handle->wtimeout ($seconds)
		757
306	Configures (or disables) the inactivity timeout.	758	Configures (or disables) the inactivity timeout.
307		759
308	=cut	760	=item $handle->timeout_reset
309		761
310	sub timeout {	762	=item $handle->rtimeout_reset
		763
		764	=item $handle->wtimeout_reset
		765
		766	Reset the activity timeout, as if data was received or sent.
		767
		768	These methods are cheap to call.
		769
		770	=cut
		771
		772	for my $dir ("", "r", "w") {
		773	my $timeout = "${dir}timeout";
		774	my $tw = "_${dir}tw";
		775	my $on_timeout = "on_${dir}timeout";
		776	my $activity = "_${dir}activity";
		777	my $cb;
		778
		779	*$on_timeout = sub {
		780	$_[0]{$on_timeout} = $_[1];
		781	};
		782
		783	*$timeout = sub {
311	my ($self, $timeout) = @_;	784	my ($self, $new_value) = @_;
312		785
		786	$new_value >= 0
		787	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		788
313	$self->{timeout} = $timeout;	789	$self->{$timeout} = $new_value;
314	$self->_timeout;	790	delete $self->{$tw}; &$cb;
315	}	791	};
316		792
		793	*{"${dir}timeout_reset"} = sub {
		794	$_[0]{$activity} = AE::now;
		795	};
		796
		797	# main workhorse:
317	# reset the timeout watcher, as neccessary	798	# reset the timeout watcher, as neccessary
318	# also check for time-outs	799	# also check for time-outs
319	sub _timeout {	800	$cb = sub {
320	my ($self) = @_;	801	my ($self) = @_;
321		802
322	if ($self->{timeout}) {	803	if ($self->{$timeout} && $self->{fh}) {
323	my $NOW = AnyEvent->now;	804	my $NOW = AE::now;
324		805
325	# when would the timeout trigger?	806	# when would the timeout trigger?
326	my $after = $self->{_activity} + $self->{timeout} - $NOW;	807	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
327		808
328	# now or in the past already?	809	# now or in the past already?
329	if ($after <= 0) {	810	if ($after <= 0) {
330	$self->{_activity} = $NOW;	811	$self->{$activity} = $NOW;
331		812
332	if ($self->{on_timeout}) {	813	if ($self->{$on_timeout}) {
333	$self->{on_timeout}->($self);	814	$self->{$on_timeout}($self);
334	} else {	815	} else {
335	$! = Errno::ETIMEDOUT;	816	$self->_error (Errno::ETIMEDOUT);
336	$self->error;	817	}
		818
		819	# callback could have changed timeout value, optimise
		820	return unless $self->{$timeout};
		821
		822	# calculate new after
		823	$after = $self->{$timeout};
337	}	824	}
338		825
339	# callbakx could have changed timeout value, optimise	826	Scalar::Util::weaken $self;
340	return unless $self->{timeout};	827	return unless $self; # ->error could have destroyed $self
341		828
342	# calculate new after	829	$self->{$tw} ||= AE::timer $after, 0, sub {
343	$after = $self->{timeout};	830	delete $self->{$tw};
		831	$cb->($self);
		832	};
		833	} else {
		834	delete $self->{$tw};
344	}	835	}
345
346	Scalar::Util::weaken $self;
347
348	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
349	delete $self->{_tw};
350	$self->_timeout;
351	});
352	} else {
353	delete $self->{_tw};
354	}	836	}
355	}	837	}
356		838
357	#############################################################################	839	#############################################################################
358		840
…		…
374	=item $handle->on_drain ($cb)	856	=item $handle->on_drain ($cb)
375		857
376	Sets the C<on_drain> callback or clears it (see the description of	858	Sets the C<on_drain> callback or clears it (see the description of
377	C<on_drain> in the constructor).	859	C<on_drain> in the constructor).
378		860
		861	This method may invoke callbacks (and therefore the handle might be
		862	destroyed after it returns).
		863
379	=cut	864	=cut
380		865
381	sub on_drain {	866	sub on_drain {
382	my ($self, $cb) = @_;	867	my ($self, $cb) = @_;
383		868
384	$self->{on_drain} = $cb;	869	$self->{on_drain} = $cb;
385		870
386	$cb->($self)	871	$cb->($self)
387	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	872	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
388	}	873	}
389		874
390	=item $handle->push_write ($data)	875	=item $handle->push_write ($data)
391		876
392	Queues the given scalar to be written. You can push as much data as you	877	Queues the given scalar to be written. You can push as much data as you
393	want (only limited by the available memory), as C<AnyEvent::Handle>	878	want (only limited by the available memory), as C<AnyEvent::Handle>
394	buffers it independently of the kernel.	879	buffers it independently of the kernel.
395		880
		881	This method may invoke callbacks (and therefore the handle might be
		882	destroyed after it returns).
		883
396	=cut	884	=cut
397		885
398	sub _drain_wbuf {	886	sub _drain_wbuf {
399	my ($self) = @_;	887	my ($self) = @_;
400		888
…		…
403	Scalar::Util::weaken $self;	891	Scalar::Util::weaken $self;
404		892
405	my $cb = sub {	893	my $cb = sub {
406	my $len = syswrite $self->{fh}, $self->{wbuf};	894	my $len = syswrite $self->{fh}, $self->{wbuf};
407		895
408	if ($len >= 0) {	896	if (defined $len) {
409	substr $self->{wbuf}, 0, $len, "";	897	substr $self->{wbuf}, 0, $len, "";
410		898
411	$self->{_activity} = AnyEvent->now;	899	$self->{_activity} = $self->{_wactivity} = AE::now;
412		900
413	$self->{on_drain}($self)	901	$self->{on_drain}($self)
414	if $self->{low_water_mark} >= length $self->{wbuf}	902	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
415	&& $self->{on_drain};	903	&& $self->{on_drain};
416		904
417	delete $self->{_ww} unless length $self->{wbuf};	905	delete $self->{_ww} unless length $self->{wbuf};
418	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	906	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
419	$self->error;	907	$self->_error ($!, 1);
420	}	908	}
421	};	909	};
422		910
423	# try to write data immediately	911	# try to write data immediately
424	$cb->();	912	$cb->() unless $self->{autocork};
425		913
426	# if still data left in wbuf, we need to poll	914	# if still data left in wbuf, we need to poll
427	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	915	$self->{_ww} = AE::io $self->{fh}, 1, $cb
428	if length $self->{wbuf};	916	if length $self->{wbuf};
429	};	917	};
430	}	918	}
431		919
432	our %WH;	920	our %WH;
433		921
		922	# deprecated
434	sub register_write_type($$) {	923	sub register_write_type($$) {
435	$WH{$_[0]} = $_[1];	924	$WH{$_[0]} = $_[1];
436	}	925	}
437		926
438	sub push_write {	927	sub push_write {
439	my $self = shift;	928	my $self = shift;
440		929
441	if (@_ > 1) {	930	if (@_ > 1) {
442	my $type = shift;	931	my $type = shift;
443		932
		933	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
444	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	934	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
445	->($self, @_);	935	->($self, @_);
446	}	936	}
447		937
		938	# we downgrade here to avoid hard-to-track-down bugs,
		939	# and diagnose the problem earlier and better.
		940
448	if ($self->{filter_w}) {	941	if ($self->{tls}) {
449	$self->{filter_w}->($self, \$_[0]);	942	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		943	&_dotls ($self) if $self->{fh};
450	} else {	944	} else {
451	$self->{wbuf} .= $_[0];	945	utf8::downgrade $self->{wbuf} .= $_[0];
452	$self->_drain_wbuf;	946	$self->_drain_wbuf if $self->{fh};
453	}	947	}
454	}	948	}
455		949
456	=item $handle->push_write (type => @args)	950	=item $handle->push_write (type => @args)
457		951
458	=item $handle->unshift_write (type => @args)
459
460	Instead of formatting your data yourself, you can also let this module do	952	Instead of formatting your data yourself, you can also let this module
461	the job by specifying a type and type-specific arguments.	953	do the job by specifying a type and type-specific arguments. You
		954	can also specify the (fully qualified) name of a package, in which
		955	case AnyEvent tries to load the package and then expects to find the
		956	C<anyevent_write_type> function inside (see "custom write types", below).
462		957
463	Predefined types are (if you have ideas for additional types, feel free to	958	Predefined types are (if you have ideas for additional types, feel free to
464	drop by and tell us):	959	drop by and tell us):
465		960
466	=over 4	961	=over 4
…		…
468	=item netstring => $string	963	=item netstring => $string
469		964
470	Formats the given value as netstring	965	Formats the given value as netstring
471	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	966	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
472		967
473	=back
474
475	=cut	968	=cut
476		969
477	register_write_type netstring => sub {	970	register_write_type netstring => sub {
478	my ($self, $string) = @_;	971	my ($self, $string) = @_;
479		972
480	sprintf "%d:%s,", (length $string), $string	973	(length $string) . ":$string,"
		974	};
		975
		976	=item packstring => $format, $data
		977
		978	An octet string prefixed with an encoded length. The encoding C<$format>
		979	uses the same format as a Perl C<pack> format, but must specify a single
		980	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		981	optional C<!>, C<< < >> or C<< > >> modifier).
		982
		983	=cut
		984
		985	register_write_type packstring => sub {
		986	my ($self, $format, $string) = @_;
		987
		988	pack "$format/a*", $string
481	};	989	};
482		990
483	=item json => $array_or_hashref	991	=item json => $array_or_hashref
484		992
485	Encodes the given hash or array reference into a JSON object. Unless you	993	Encodes the given hash or array reference into a JSON object. Unless you
…		…
510	Other languages could read single lines terminated by a newline and pass	1018	Other languages could read single lines terminated by a newline and pass
511	this line into their JSON decoder of choice.	1019	this line into their JSON decoder of choice.
512		1020
513	=cut	1021	=cut
514		1022
		1023	sub json_coder() {
		1024	eval { require JSON::XS; JSON::XS->new->utf8 }
		1025	|| do { require JSON; JSON->new->utf8 }
		1026	}
		1027
515	register_write_type json => sub {	1028	register_write_type json => sub {
516	my ($self, $ref) = @_;	1029	my ($self, $ref) = @_;
517		1030
518	require JSON;	1031	my $json = $self->{json} ||= json_coder;
519		1032
520	$self->{json} ? $self->{json}->encode ($ref)	1033	$json->encode ($ref)
521	: JSON::encode_json ($ref)
522	};	1034	};
523		1035
524	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	1036	=item storable => $reference
525		1037
526	This function (not method) lets you add your own types to C<push_write>.	1038	Freezes the given reference using L<Storable> and writes it to the
		1039	handle. Uses the C<nfreeze> format.
		1040
		1041	=cut
		1042
		1043	register_write_type storable => sub {
		1044	my ($self, $ref) = @_;
		1045
		1046	require Storable;
		1047
		1048	pack "w/a*", Storable::nfreeze ($ref)
		1049	};
		1050
		1051	=back
		1052
		1053	=item $handle->push_shutdown
		1054
		1055	Sometimes you know you want to close the socket after writing your data
		1056	before it was actually written. One way to do that is to replace your
		1057	C<on_drain> handler by a callback that shuts down the socket (and set
		1058	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1059	replaces the C<on_drain> callback with:
		1060
		1061	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		1062
		1063	This simply shuts down the write side and signals an EOF condition to the
		1064	the peer.
		1065
		1066	You can rely on the normal read queue and C<on_eof> handling
		1067	afterwards. This is the cleanest way to close a connection.
		1068
		1069	This method may invoke callbacks (and therefore the handle might be
		1070	destroyed after it returns).
		1071
		1072	=cut
		1073
		1074	sub push_shutdown {
		1075	my ($self) = @_;
		1076
		1077	delete $self->{low_water_mark};
		1078	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1079	}
		1080
		1081	=item custom write types - Package::anyevent_write_type $handle, @args
		1082
		1083	Instead of one of the predefined types, you can also specify the name of
		1084	a package. AnyEvent will try to load the package and then expects to find
		1085	a function named C<anyevent_write_type> inside. If it isn't found, it
		1086	progressively tries to load the parent package until it either finds the
		1087	function (good) or runs out of packages (bad).
		1088
527	Whenever the given C<type> is used, C<push_write> will invoke the code	1089	Whenever the given C<type> is used, C<push_write> will the function with
528	reference with the handle object and the remaining arguments.	1090	the handle object and the remaining arguments.
529		1091
530	The code reference is supposed to return a single octet string that will	1092	The function is supposed to return a single octet string that will be
531	be appended to the write buffer.	1093	appended to the write buffer, so you cna mentally treat this function as a
		1094	"arguments to on-the-wire-format" converter.
532		1095
533	Note that this is a function, and all types registered this way will be	1096	Example: implement a custom write type C<join> that joins the remaining
534	global, so try to use unique names.	1097	arguments using the first one.
		1098
		1099	$handle->push_write (My::Type => " ", 1,2,3);
		1100
		1101	# uses the following package, which can be defined in the "My::Type" or in
		1102	# the "My" modules to be auto-loaded, or just about anywhere when the
		1103	# My::Type::anyevent_write_type is defined before invoking it.
		1104
		1105	package My::Type;
		1106
		1107	sub anyevent_write_type {
		1108	my ($handle, $delim, @args) = @_;
		1109
		1110	join $delim, @args
		1111	}
535		1112
536	=cut	1113	=cut
537		1114
538	#############################################################################	1115	#############################################################################
539		1116
…		…
548	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1125	ways, the "simple" way, using only C<on_read> and the "complex" way, using
549	a queue.	1126	a queue.
550		1127
551	In the simple case, you just install an C<on_read> callback and whenever	1128	In the simple case, you just install an C<on_read> callback and whenever
552	new data arrives, it will be called. You can then remove some data (if	1129	new data arrives, it will be called. You can then remove some data (if
553	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	1130	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
554	or not.	1131	leave the data there if you want to accumulate more (e.g. when only a
		1132	partial message has been received so far), or change the read queue with
		1133	e.g. C<push_read>.
555		1134
556	In the more complex case, you want to queue multiple callbacks. In this	1135	In the more complex case, you want to queue multiple callbacks. In this
557	case, AnyEvent::Handle will call the first queued callback each time new	1136	case, AnyEvent::Handle will call the first queued callback each time new
558	data arrives and removes it when it has done its job (see C<push_read>,	1137	data arrives (also the first time it is queued) and remove it when it has
559	below).	1138	done its job (see C<push_read>, below).
560		1139
561	This way you can, for example, push three line-reads, followed by reading	1140	This way you can, for example, push three line-reads, followed by reading
562	a chunk of data, and AnyEvent::Handle will execute them in order.	1141	a chunk of data, and AnyEvent::Handle will execute them in order.
563		1142
564	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	1143	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
565	the specified number of bytes which give an XML datagram.	1144	the specified number of bytes which give an XML datagram.
566		1145
567	# in the default state, expect some header bytes	1146	# in the default state, expect some header bytes
568	$handle->on_read (sub {	1147	$handle->on_read (sub {
569	# some data is here, now queue the length-header-read (4 octets)	1148	# some data is here, now queue the length-header-read (4 octets)
570	shift->unshift_read_chunk (4, sub {	1149	shift->unshift_read (chunk => 4, sub {
571	# header arrived, decode	1150	# header arrived, decode
572	my $len = unpack "N", $_[1];	1151	my $len = unpack "N", $_[1];
573		1152
574	# now read the payload	1153	# now read the payload
575	shift->unshift_read_chunk ($len, sub {	1154	shift->unshift_read (chunk => $len, sub {
576	my $xml = $_[1];	1155	my $xml = $_[1];
577	# handle xml	1156	# handle xml
578	});	1157	});
579	});	1158	});
580	});	1159	});
581		1160
582	Example 2: Implement a client for a protocol that replies either with	1161	Example 2: Implement a client for a protocol that replies either with "OK"
583	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1162	and another line or "ERROR" for the first request that is sent, and 64
584	second request. Due tot he availability of a full queue, we can just	1163	bytes for the second request. Due to the availability of a queue, we can
585	pipeline sending both requests and manipulate the queue as necessary in	1164	just pipeline sending both requests and manipulate the queue as necessary
586	the callbacks:	1165	in the callbacks.
587		1166
588	# request one	1167	When the first callback is called and sees an "OK" response, it will
		1168	C<unshift> another line-read. This line-read will be queued I<before> the
		1169	64-byte chunk callback.
		1170
		1171	# request one, returns either "OK + extra line" or "ERROR"
589	$handle->push_write ("request 1\015\012");	1172	$handle->push_write ("request 1\015\012");
590		1173
591	# we expect "ERROR" or "OK" as response, so push a line read	1174	# we expect "ERROR" or "OK" as response, so push a line read
592	$handle->push_read_line (sub {	1175	$handle->push_read (line => sub {
593	# if we got an "OK", we have to _prepend_ another line,	1176	# if we got an "OK", we have to _prepend_ another line,
594	# so it will be read before the second request reads its 64 bytes	1177	# so it will be read before the second request reads its 64 bytes
595	# which are already in the queue when this callback is called	1178	# which are already in the queue when this callback is called
596	# we don't do this in case we got an error	1179	# we don't do this in case we got an error
597	if ($_[1] eq "OK") {	1180	if ($_[1] eq "OK") {
598	$_[0]->unshift_read_line (sub {	1181	$_[0]->unshift_read (line => sub {
599	my $response = $_[1];	1182	my $response = $_[1];
600	...	1183	...
601	});	1184	});
602	}	1185	}
603	});	1186	});
604		1187
605	# request two	1188	# request two, simply returns 64 octets
606	$handle->push_write ("request 2\015\012");	1189	$handle->push_write ("request 2\015\012");
607		1190
608	# simply read 64 bytes, always	1191	# simply read 64 bytes, always
609	$handle->push_read_chunk (64, sub {	1192	$handle->push_read (chunk => 64, sub {
610	my $response = $_[1];	1193	my $response = $_[1];
611	...	1194	...
612	});	1195	});
613		1196
614	=over 4	1197	=over 4
615		1198
616	=cut	1199	=cut
617		1200
618	sub _drain_rbuf {	1201	sub _drain_rbuf {
619	my ($self) = @_;	1202	my ($self) = @_;
		1203
		1204	# avoid recursion
		1205	return if $self->{_skip_drain_rbuf};
		1206	local $self->{_skip_drain_rbuf} = 1;
		1207
		1208	while () {
		1209	# we need to use a separate tls read buffer, as we must not receive data while
		1210	# we are draining the buffer, and this can only happen with TLS.
		1211	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1212	if exists $self->{_tls_rbuf};
		1213
		1214	my $len = length $self->{rbuf};
		1215
		1216	if (my $cb = shift @{ $self->{_queue} }) {
		1217	unless ($cb->($self)) {
		1218	# no progress can be made
		1219	# (not enough data and no data forthcoming)
		1220	$self->_error (Errno::EPIPE, 1), return
		1221	if $self->{_eof};
		1222
		1223	unshift @{ $self->{_queue} }, $cb;
		1224	last;
		1225	}
		1226	} elsif ($self->{on_read}) {
		1227	last unless $len;
		1228
		1229	$self->{on_read}($self);
		1230
		1231	if (
		1232	$len == length $self->{rbuf} # if no data has been consumed
		1233	&& !@{ $self->{_queue} } # and the queue is still empty
		1234	&& $self->{on_read} # but we still have on_read
		1235	) {
		1236	# no further data will arrive
		1237	# so no progress can be made
		1238	$self->_error (Errno::EPIPE, 1), return
		1239	if $self->{_eof};
		1240
		1241	last; # more data might arrive
		1242	}
		1243	} else {
		1244	# read side becomes idle
		1245	delete $self->{_rw} unless $self->{tls};
		1246	last;
		1247	}
		1248	}
		1249
		1250	if ($self->{_eof}) {
		1251	$self->{on_eof}
		1252	? $self->{on_eof}($self)
		1253	: $self->_error (0, 1, "Unexpected end-of-file");
		1254
		1255	return;
		1256	}
620		1257
621	if (	1258	if (
622	defined $self->{rbuf_max}	1259	defined $self->{rbuf_max}
623	&& $self->{rbuf_max} < length $self->{rbuf}	1260	&& $self->{rbuf_max} < length $self->{rbuf}
624	) {	1261	) {
625	$! = &Errno::ENOSPC;	1262	$self->_error (Errno::ENOSPC, 1), return;
626	$self->error;
627	}	1263	}
628		1264
629	return if $self->{in_drain};	1265	# may need to restart read watcher
630	local $self->{in_drain} = 1;	1266	unless ($self->{_rw}) {
631		1267	$self->start_read
632	while (my $len = length $self->{rbuf}) {	1268	if $self->{on_read} || @{ $self->{_queue} };
633	no strict 'refs';
634	if (my $cb = shift @{ $self->{_queue} }) {
635	unless ($cb->($self)) {
636	if ($self->{_eof}) {
637	# no progress can be made (not enough data and no data forthcoming)
638	$! = &Errno::EPIPE;
639	$self->error;
640	}
641
642	unshift @{ $self->{_queue} }, $cb;
643	return;
644	}
645	} elsif ($self->{on_read}) {
646	$self->{on_read}($self);
647
648	if (
649	$self->{_eof} # if no further data will arrive
650	&& $len == length $self->{rbuf} # and no data has been consumed
651	&& !@{ $self->{_queue} } # and the queue is still empty
652	&& $self->{on_read} # and we still want to read data
653	) {
654	# then no progress can be made
655	$! = &Errno::EPIPE;
656	$self->error;
657	}
658	} else {
659	# read side becomes idle
660	delete $self->{_rw};
661	return;
662	}
663	}
664
665	if ($self->{_eof}) {
666	$self->_shutdown;
667	$self->{on_eof}($self)
668	if $self->{on_eof};
669	}	1269	}
670	}	1270	}
671		1271
672	=item $handle->on_read ($cb)	1272	=item $handle->on_read ($cb)
673		1273
674	This replaces the currently set C<on_read> callback, or clears it (when	1274	This replaces the currently set C<on_read> callback, or clears it (when
675	the new callback is C<undef>). See the description of C<on_read> in the	1275	the new callback is C<undef>). See the description of C<on_read> in the
676	constructor.	1276	constructor.
677		1277
		1278	This method may invoke callbacks (and therefore the handle might be
		1279	destroyed after it returns).
		1280
678	=cut	1281	=cut
679		1282
680	sub on_read {	1283	sub on_read {
681	my ($self, $cb) = @_;	1284	my ($self, $cb) = @_;
682		1285
683	$self->{on_read} = $cb;	1286	$self->{on_read} = $cb;
		1287	$self->_drain_rbuf if $cb;
684	}	1288	}
685		1289
686	=item $handle->rbuf	1290	=item $handle->rbuf
687		1291
688	Returns the read buffer (as a modifiable lvalue).	1292	Returns the read buffer (as a modifiable lvalue). You can also access the
		1293	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1294	much faster, and no less clean).
689		1295
690	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1296	The only operation allowed on the read buffer (apart from looking at it)
691	you want.	1297	is removing data from its beginning. Otherwise modifying or appending to
		1298	it is not allowed and will lead to hard-to-track-down bugs.
692		1299
693	NOTE: The read buffer should only be used or modified if the C<on_read>,	1300	NOTE: The read buffer should only be used or modified in the C<on_read>
694	C<push_read> or C<unshift_read> methods are used. The other read methods	1301	callback or when C<push_read> or C<unshift_read> are used with a single
695	automatically manage the read buffer.	1302	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1303	will manage the read buffer on their own.
696		1304
697	=cut	1305	=cut
698		1306
699	sub rbuf : lvalue {	1307	sub rbuf : lvalue {
700	$_[0]{rbuf}	1308	$_[0]{rbuf}
…		…
717		1325
718	If enough data was available, then the callback must remove all data it is	1326	If enough data was available, then the callback must remove all data it is
719	interested in (which can be none at all) and return a true value. After returning	1327	interested in (which can be none at all) and return a true value. After returning
720	true, it will be removed from the queue.	1328	true, it will be removed from the queue.
721		1329
		1330	These methods may invoke callbacks (and therefore the handle might be
		1331	destroyed after it returns).
		1332
722	=cut	1333	=cut
723		1334
724	our %RH;	1335	our %RH;
725		1336
726	sub register_read_type($$) {	1337	sub register_read_type($$) {
…		…
732	my $cb = pop;	1343	my $cb = pop;
733		1344
734	if (@_) {	1345	if (@_) {
735	my $type = shift;	1346	my $type = shift;
736		1347
		1348	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
737	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1349	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
738	->($self, $cb, @_);	1350	->($self, $cb, @_);
739	}	1351	}
740		1352
741	push @{ $self->{_queue} }, $cb;	1353	push @{ $self->{_queue} }, $cb;
742	$self->_drain_rbuf;	1354	$self->_drain_rbuf;
…		…
747	my $cb = pop;	1359	my $cb = pop;
748		1360
749	if (@_) {	1361	if (@_) {
750	my $type = shift;	1362	my $type = shift;
751		1363
		1364	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
752	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1365	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
753	->($self, $cb, @_);	1366	->($self, $cb, @_);
754	}	1367	}
755
756		1368
757	unshift @{ $self->{_queue} }, $cb;	1369	unshift @{ $self->{_queue} }, $cb;
758	$self->_drain_rbuf;	1370	$self->_drain_rbuf;
759	}	1371	}
760		1372
…		…
762		1374
763	=item $handle->unshift_read (type => @args, $cb)	1375	=item $handle->unshift_read (type => @args, $cb)
764		1376
765	Instead of providing a callback that parses the data itself you can chose	1377	Instead of providing a callback that parses the data itself you can chose
766	between a number of predefined parsing formats, for chunks of data, lines	1378	between a number of predefined parsing formats, for chunks of data, lines
767	etc.	1379	etc. You can also specify the (fully qualified) name of a package, in
		1380	which case AnyEvent tries to load the package and then expects to find the
		1381	C<anyevent_read_type> function inside (see "custom read types", below).
768		1382
769	Predefined types are (if you have ideas for additional types, feel free to	1383	Predefined types are (if you have ideas for additional types, feel free to
770	drop by and tell us):	1384	drop by and tell us):
771		1385
772	=over 4	1386	=over 4
…		…
793	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1407	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
794	1	1408	1
795	}	1409	}
796	};	1410	};
797		1411
798	# compatibility with older API
799	sub push_read_chunk {
800	$_[0]->push_read (chunk => $_[1], $_[2]);
801	}
802
803	sub unshift_read_chunk {
804	$_[0]->unshift_read (chunk => $_[1], $_[2]);
805	}
806
807	=item line => [$eol, ]$cb->($handle, $line, $eol)	1412	=item line => [$eol, ]$cb->($handle, $line, $eol)
808		1413
809	The callback will be called only once a full line (including the end of	1414	The callback will be called only once a full line (including the end of
810	line marker, C<$eol>) has been read. This line (excluding the end of line	1415	line marker, C<$eol>) has been read. This line (excluding the end of line
811	marker) will be passed to the callback as second argument (C<$line>), and	1416	marker) will be passed to the callback as second argument (C<$line>), and
…		…
826	=cut	1431	=cut
827		1432
828	register_read_type line => sub {	1433	register_read_type line => sub {
829	my ($self, $cb, $eol) = @_;	1434	my ($self, $cb, $eol) = @_;
830		1435
831	$eol = qr|(\015?\012)| if @_ < 3;	1436	if (@_ < 3) {
832	$eol = quotemeta $eol unless ref $eol;	1437	# this is more than twice as fast as the generic code below
833	$eol = qr|^(.*?)($eol)|s;
834
835	sub {	1438	sub {
836	$_[0]{rbuf} =~ s/$eol// or return;	1439	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
837		1440
838	$cb->($_[0], $1, $2);	1441	$cb->($_[0], $1, $2);
839	1
840	}
841	};
842
843	# compatibility with older API
844	sub push_read_line {
845	my $self = shift;
846	$self->push_read (line => @_);
847	}
848
849	sub unshift_read_line {
850	my $self = shift;
851	$self->unshift_read (line => @_);
852	}
853
854	=item netstring => $cb->($handle, $string)
855
856	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
857
858	Throws an error with C<$!> set to EBADMSG on format violations.
859
860	=cut
861
862	register_read_type netstring => sub {
863	my ($self, $cb) = @_;
864
865	sub {
866	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
867	if ($_[0]{rbuf} =~ /[^0-9]/) {
868	$! = &Errno::EBADMSG;
869	$self->error;
870	}	1442	1
871	return;
872	}	1443	}
		1444	} else {
		1445	$eol = quotemeta $eol unless ref $eol;
		1446	$eol = qr|^(.*?)($eol)|s;
873		1447
874	my $len = $1;	1448	sub {
		1449	$_[0]{rbuf} =~ s/$eol// or return;
875		1450
876	$self->unshift_read (chunk => $len, sub {	1451	$cb->($_[0], $1, $2);
877	my $string = $_[1];
878	$_[0]->unshift_read (chunk => 1, sub {
879	if ($_[1] eq ",") {
880	$cb->($_[0], $string);
881	} else {
882	$! = &Errno::EBADMSG;
883	$self->error;
884	}
885	});	1452	1
886	});	1453	}
887
888	1
889	}	1454	}
890	};	1455	};
891		1456
892	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)	1457	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
893		1458
…		…
913	the receive buffer when neither C<$accept> nor C<$reject> match,	1478	the receive buffer when neither C<$accept> nor C<$reject> match,
914	and everything preceding and including the match will be accepted	1479	and everything preceding and including the match will be accepted
915	unconditionally. This is useful to skip large amounts of data that you	1480	unconditionally. This is useful to skip large amounts of data that you
916	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1481	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
917	have to start matching from the beginning. This is purely an optimisation	1482	have to start matching from the beginning. This is purely an optimisation
918	and is usually worth only when you expect more than a few kilobytes.	1483	and is usually worth it only when you expect more than a few kilobytes.
919		1484
920	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1485	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
921	expect the header to be very large (it isn't in practise, but...), we use	1486	expect the header to be very large (it isn't in practice, but...), we use
922	a skip regex to skip initial portions. The skip regex is tricky in that	1487	a skip regex to skip initial portions. The skip regex is tricky in that
923	it only accepts something not ending in either \015 or \012, as these are	1488	it only accepts something not ending in either \015 or \012, as these are
924	required for the accept regex.	1489	required for the accept regex.
925		1490
926	$handle->push_read (regex =>	1491	$handle->push_read (regex =>
…		…
945	return 1;	1510	return 1;
946	}	1511	}
947		1512
948	# reject	1513	# reject
949	if ($reject && $$rbuf =~ $reject) {	1514	if ($reject && $$rbuf =~ $reject) {
950	$! = &Errno::EBADMSG;	1515	$self->_error (Errno::EBADMSG);
951	$self->error;
952	}	1516	}
953		1517
954	# skip	1518	# skip
955	if ($skip && $$rbuf =~ $skip) {	1519	if ($skip && $$rbuf =~ $skip) {
956	$data .= substr $$rbuf, 0, $+[0], "";	1520	$data .= substr $$rbuf, 0, $+[0], "";
…		…
958		1522
959	()	1523	()
960	}	1524	}
961	};	1525	};
962		1526
		1527	=item netstring => $cb->($handle, $string)
		1528
		1529	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1530
		1531	Throws an error with C<$!> set to EBADMSG on format violations.
		1532
		1533	=cut
		1534
		1535	register_read_type netstring => sub {
		1536	my ($self, $cb) = @_;
		1537
		1538	sub {
		1539	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1540	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1541	$self->_error (Errno::EBADMSG);
		1542	}
		1543	return;
		1544	}
		1545
		1546	my $len = $1;
		1547
		1548	$self->unshift_read (chunk => $len, sub {
		1549	my $string = $_[1];
		1550	$_[0]->unshift_read (chunk => 1, sub {
		1551	if ($_[1] eq ",") {
		1552	$cb->($_[0], $string);
		1553	} else {
		1554	$self->_error (Errno::EBADMSG);
		1555	}
		1556	});
		1557	});
		1558
		1559	1
		1560	}
		1561	};
		1562
		1563	=item packstring => $format, $cb->($handle, $string)
		1564
		1565	An octet string prefixed with an encoded length. The encoding C<$format>
		1566	uses the same format as a Perl C<pack> format, but must specify a single
		1567	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1568	optional C<!>, C<< < >> or C<< > >> modifier).
		1569
		1570	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1571	EPP uses a prefix of C<N> (4 octtes).
		1572
		1573	Example: read a block of data prefixed by its length in BER-encoded
		1574	format (very efficient).
		1575
		1576	$handle->push_read (packstring => "w", sub {
		1577	my ($handle, $data) = @_;
		1578	});
		1579
		1580	=cut
		1581
		1582	register_read_type packstring => sub {
		1583	my ($self, $cb, $format) = @_;
		1584
		1585	sub {
		1586	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1587	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1588	or return;
		1589
		1590	$format = length pack $format, $len;
		1591
		1592	# bypass unshift if we already have the remaining chunk
		1593	if ($format + $len <= length $_[0]{rbuf}) {
		1594	my $data = substr $_[0]{rbuf}, $format, $len;
		1595	substr $_[0]{rbuf}, 0, $format + $len, "";
		1596	$cb->($_[0], $data);
		1597	} else {
		1598	# remove prefix
		1599	substr $_[0]{rbuf}, 0, $format, "";
		1600
		1601	# read remaining chunk
		1602	$_[0]->unshift_read (chunk => $len, $cb);
		1603	}
		1604
		1605	1
		1606	}
		1607	};
		1608
963	=item json => $cb->($handle, $hash_or_arrayref)	1609	=item json => $cb->($handle, $hash_or_arrayref)
964		1610
965	Reads a JSON object or array, decodes it and passes it to the callback.	1611	Reads a JSON object or array, decodes it and passes it to the
		1612	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
966		1613
967	If a C<json> object was passed to the constructor, then that will be used	1614	If a C<json> object was passed to the constructor, then that will be used
968	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1615	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
969		1616
970	This read type uses the incremental parser available with JSON version	1617	This read type uses the incremental parser available with JSON version
…		…
977	the C<json> write type description, above, for an actual example.	1624	the C<json> write type description, above, for an actual example.
978		1625
979	=cut	1626	=cut
980		1627
981	register_read_type json => sub {	1628	register_read_type json => sub {
982	my ($self, $cb, $accept, $reject, $skip) = @_;	1629	my ($self, $cb) = @_;
983		1630
984	require JSON;	1631	my $json = $self->{json} ||= json_coder;
985		1632
986	my $data;	1633	my $data;
987	my $rbuf = \$self->{rbuf};	1634	my $rbuf = \$self->{rbuf};
988		1635
989	my $json = $self->{json} ||= JSON->new->utf8;
990
991	sub {	1636	sub {
992	my $ref = $json->incr_parse ($self->{rbuf});	1637	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
993		1638
994	if ($ref) {	1639	if ($ref) {
995	$self->{rbuf} = $json->incr_text;	1640	$self->{rbuf} = $json->incr_text;
996	$json->incr_text = "";	1641	$json->incr_text = "";
997	$cb->($self, $ref);	1642	$cb->($self, $ref);
998		1643
999	1	1644	1
		1645	} elsif ($@) {
		1646	# error case
		1647	$json->incr_skip;
		1648
		1649	$self->{rbuf} = $json->incr_text;
		1650	$json->incr_text = "";
		1651
		1652	$self->_error (Errno::EBADMSG);
		1653
		1654	()
1000	} else {	1655	} else {
1001	$self->{rbuf} = "";	1656	$self->{rbuf} = "";
		1657
1002	()	1658	()
1003	}	1659	}
1004	}	1660	}
1005	};	1661	};
1006		1662
		1663	=item storable => $cb->($handle, $ref)
		1664
		1665	Deserialises a L<Storable> frozen representation as written by the
		1666	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1667	data).
		1668
		1669	Raises C<EBADMSG> error if the data could not be decoded.
		1670
		1671	=cut
		1672
		1673	register_read_type storable => sub {
		1674	my ($self, $cb) = @_;
		1675
		1676	require Storable;
		1677
		1678	sub {
		1679	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1680	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1681	or return;
		1682
		1683	my $format = length pack "w", $len;
		1684
		1685	# bypass unshift if we already have the remaining chunk
		1686	if ($format + $len <= length $_[0]{rbuf}) {
		1687	my $data = substr $_[0]{rbuf}, $format, $len;
		1688	substr $_[0]{rbuf}, 0, $format + $len, "";
		1689	$cb->($_[0], Storable::thaw ($data));
		1690	} else {
		1691	# remove prefix
		1692	substr $_[0]{rbuf}, 0, $format, "";
		1693
		1694	# read remaining chunk
		1695	$_[0]->unshift_read (chunk => $len, sub {
		1696	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1697	$cb->($_[0], $ref);
		1698	} else {
		1699	$self->_error (Errno::EBADMSG);
		1700	}
		1701	});
		1702	}
		1703
		1704	1
		1705	}
		1706	};
		1707
1007	=back	1708	=back
1008		1709
1009	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)	1710	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1010		1711
1011	This function (not method) lets you add your own types to C<push_read>.	1712	Instead of one of the predefined types, you can also specify the name
		1713	of a package. AnyEvent will try to load the package and then expects to
		1714	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1715	progressively tries to load the parent package until it either finds the
		1716	function (good) or runs out of packages (bad).
1012		1717
1013	Whenever the given C<type> is used, C<push_read> will invoke the code	1718	Whenever this type is used, C<push_read> will invoke the function with the
1014	reference with the handle object, the callback and the remaining	1719	handle object, the original callback and the remaining arguments.
1015	arguments.
1016		1720
1017	The code reference is supposed to return a callback (usually a closure)	1721	The function is supposed to return a callback (usually a closure) that
1018	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1722	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1723	mentally treat the function as a "configurable read type to read callback"
		1724	converter.
1019		1725
1020	It should invoke the passed callback when it is done reading (remember to	1726	It should invoke the original callback when it is done reading (remember
1021	pass C<$handle> as first argument as all other callbacks do that).	1727	to pass C<$handle> as first argument as all other callbacks do that,
		1728	although there is no strict requirement on this).
1022		1729
1023	Note that this is a function, and all types registered this way will be
1024	global, so try to use unique names.
1025
1026	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1730	For examples, see the source of this module (F<perldoc -m
1027	search for C<register_read_type>)).	1731	AnyEvent::Handle>, search for C<register_read_type>)).
1028		1732
1029	=item $handle->stop_read	1733	=item $handle->stop_read
1030		1734
1031	=item $handle->start_read	1735	=item $handle->start_read
1032		1736
1033	In rare cases you actually do not want to read anything from the	1737	In rare cases you actually do not want to read anything from the
1034	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1738	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
1035	any queued callbacks will be executed then. To start reading again, call	1739	any queued callbacks will be executed then. To start reading again, call
1036	C<start_read>.	1740	C<start_read>.
1037		1741
		1742	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1743	you change the C<on_read> callback or push/unshift a read callback, and it
		1744	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1745	there are any read requests in the queue.
		1746
		1747	These methods will have no effect when in TLS mode (as TLS doesn't support
		1748	half-duplex connections).
		1749
1038	=cut	1750	=cut
1039		1751
1040	sub stop_read {	1752	sub stop_read {
1041	my ($self) = @_;	1753	my ($self) = @_;
1042		1754
1043	delete $self->{_rw};	1755	delete $self->{_rw} unless $self->{tls};
1044	}	1756	}
1045		1757
1046	sub start_read {	1758	sub start_read {
1047	my ($self) = @_;	1759	my ($self) = @_;
1048		1760
1049	unless ($self->{_rw} || $self->{_eof}) {	1761	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1050	Scalar::Util::weaken $self;	1762	Scalar::Util::weaken $self;
1051		1763
1052	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1764	$self->{_rw} = AE::io $self->{fh}, 0, sub {
1053	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1765	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1054	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1766	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1055		1767
1056	if ($len > 0) {	1768	if ($len > 0) {
1057	$self->{_activity} = AnyEvent->now;	1769	$self->{_activity} = $self->{_ractivity} = AE::now;
1058		1770
1059	$self->{filter_r}	1771	if ($self->{tls}) {
1060	? $self->{filter_r}->($self, $rbuf)	1772	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1773
		1774	&_dotls ($self);
		1775	} else {
1061	: $self->_drain_rbuf;	1776	$self->_drain_rbuf;
		1777	}
		1778
		1779	if ($len == $self->{read_size}) {
		1780	$self->{read_size} *= 2;
		1781	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1782	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		1783	}
1062		1784
1063	} elsif (defined $len) {	1785	} elsif (defined $len) {
1064	delete $self->{_rw};	1786	delete $self->{_rw};
1065	delete $self->{_ww};
1066	delete $self->{_tw};
1067	$self->{_eof} = 1;	1787	$self->{_eof} = 1;
1068	$self->_drain_rbuf;	1788	$self->_drain_rbuf;
1069		1789
1070	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1790	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1071	return $self->error;	1791	return $self->_error ($!, 1);
1072	}	1792	}
1073	});	1793	};
1074	}	1794	}
1075	}	1795	}
1076		1796
		1797	our $ERROR_SYSCALL;
		1798	our $ERROR_WANT_READ;
		1799
		1800	sub _tls_error {
		1801	my ($self, $err) = @_;
		1802
		1803	return $self->_error ($!, 1)
		1804	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1805
		1806	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1807
		1808	# reduce error string to look less scary
		1809	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1810
		1811	if ($self->{_on_starttls}) {
		1812	(delete $self->{_on_starttls})->($self, undef, $err);
		1813	&_freetls;
		1814	} else {
		1815	&_freetls;
		1816	$self->_error (Errno::EPROTO, 1, $err);
		1817	}
		1818	}
		1819
		1820	# poll the write BIO and send the data if applicable
		1821	# also decode read data if possible
		1822	# this is basiclaly our TLS state machine
		1823	# more efficient implementations are possible with openssl,
		1824	# but not with the buggy and incomplete Net::SSLeay.
1077	sub _dotls {	1825	sub _dotls {
1078	my ($self) = @_;	1826	my ($self) = @_;
1079		1827
		1828	my $tmp;
		1829
1080	if (length $self->{_tls_wbuf}) {	1830	if (length $self->{_tls_wbuf}) {
1081	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1831	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1082	substr $self->{_tls_wbuf}, 0, $len, "";	1832	substr $self->{_tls_wbuf}, 0, $tmp, "";
1083	}	1833	}
1084	}
1085		1834
		1835	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1836	return $self->_tls_error ($tmp)
		1837	if $tmp != $ERROR_WANT_READ
		1838	&& ($tmp != $ERROR_SYSCALL || $!);
		1839	}
		1840
		1841	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1842	unless (length $tmp) {
		1843	$self->{_on_starttls}
		1844	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1845	&_freetls;
		1846
		1847	if ($self->{on_stoptls}) {
		1848	$self->{on_stoptls}($self);
		1849	return;
		1850	} else {
		1851	# let's treat SSL-eof as we treat normal EOF
		1852	delete $self->{_rw};
		1853	$self->{_eof} = 1;
		1854	}
		1855	}
		1856
		1857	$self->{_tls_rbuf} .= $tmp;
		1858	$self->_drain_rbuf;
		1859	$self->{tls} or return; # tls session might have gone away in callback
		1860	}
		1861
		1862	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1863	return $self->_tls_error ($tmp)
		1864	if $tmp != $ERROR_WANT_READ
		1865	&& ($tmp != $ERROR_SYSCALL || $!);
		1866
1086	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1867	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1087	$self->{wbuf} .= $buf;	1868	$self->{wbuf} .= $tmp;
1088	$self->_drain_wbuf;	1869	$self->_drain_wbuf;
		1870	$self->{tls} or return; # tls session might have gone away in callback
1089	}	1871	}
1090		1872
1091	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {	1873	$self->{_on_starttls}
1092	$self->{rbuf} .= $buf;	1874	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1093	$self->_drain_rbuf;	1875	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1094	}
1095
1096	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1097
1098	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1099	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1100	$self->error;
1101	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1102	$! = &Errno::EIO;
1103	$self->error;
1104	}
1105
1106	# all others are fine for our purposes
1107	}
1108	}	1876	}
1109		1877
1110	=item $handle->starttls ($tls[, $tls_ctx])	1878	=item $handle->starttls ($tls[, $tls_ctx])
1111		1879
1112	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1880	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1113	object is created, you can also do that at a later time by calling	1881	object is created, you can also do that at a later time by calling
1114	C<starttls>.	1882	C<starttls>.
1115		1883
		1884	Starting TLS is currently an asynchronous operation - when you push some
		1885	write data and then call C<< ->starttls >> then TLS negotiation will start
		1886	immediately, after which the queued write data is then sent.
		1887
1116	The first argument is the same as the C<tls> constructor argument (either	1888	The first argument is the same as the C<tls> constructor argument (either
1117	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1889	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1118		1890
1119	The second argument is the optional C<Net::SSLeay::CTX> object that is	1891	The second argument is the optional C<AnyEvent::TLS> object that is used
1120	used when AnyEvent::Handle has to create its own TLS connection object.	1892	when AnyEvent::Handle has to create its own TLS connection object, or
		1893	a hash reference with C<< key => value >> pairs that will be used to
		1894	construct a new context.
1121		1895
1122	The TLS connection object will end up in C<< $handle->{tls} >> after this	1896	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1123	call and can be used or changed to your liking. Note that the handshake	1897	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1124	might have already started when this function returns.	1898	changed to your liking. Note that the handshake might have already started
		1899	when this function returns.
1125		1900
1126	=cut	1901	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1902	handshakes on the same stream. It is best to not attempt to use the
		1903	stream after stopping TLS.
1127		1904
1128	# TODO: maybe document...	1905	This method may invoke callbacks (and therefore the handle might be
		1906	destroyed after it returns).
		1907
		1908	=cut
		1909
		1910	our %TLS_CACHE; #TODO not yet documented, should we?
		1911
1129	sub starttls {	1912	sub starttls {
1130	my ($self, $ssl, $ctx) = @_;	1913	my ($self, $tls, $ctx) = @_;
1131		1914
1132	$self->stoptls;	1915	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1916	if $self->{tls};
1133		1917
1134	if ($ssl eq "accept") {	1918	$self->{tls} = $tls;
1135	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1919	$self->{tls_ctx} = $ctx if @_ > 2;
1136	Net::SSLeay::set_accept_state ($ssl);	1920
1137	} elsif ($ssl eq "connect") {	1921	return unless $self->{fh};
1138	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1922
1139	Net::SSLeay::set_connect_state ($ssl);	1923	require Net::SSLeay;
		1924
		1925	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		1926	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1927
		1928	$tls = delete $self->{tls};
		1929	$ctx = $self->{tls_ctx};
		1930
		1931	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1932
		1933	if ("HASH" eq ref $ctx) {
		1934	require AnyEvent::TLS;
		1935
		1936	if ($ctx->{cache}) {
		1937	my $key = $ctx+0;
		1938	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1939	} else {
		1940	$ctx = new AnyEvent::TLS %$ctx;
		1941	}
		1942	}
1140	}	1943
1141		1944	$self->{tls_ctx} = $ctx || TLS_CTX ();
1142	$self->{tls} = $ssl;	1945	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1143		1946
1144	# basically, this is deep magic (because SSL_read should have the same issues)	1947	# basically, this is deep magic (because SSL_read should have the same issues)
1145	# but the openssl maintainers basically said: "trust us, it just works".	1948	# but the openssl maintainers basically said: "trust us, it just works".
1146	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1949	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1147	# and mismaintained ssleay-module doesn't even offer them).	1950	# and mismaintained ssleay-module doesn't even offer them).
1148	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1951	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1952	#
		1953	# in short: this is a mess.
		1954	#
		1955	# note that we do not try to keep the length constant between writes as we are required to do.
		1956	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1957	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1958	# have identity issues in that area.
1149	Net::SSLeay::CTX_set_mode ($self->{tls},	1959	# Net::SSLeay::CTX_set_mode ($ssl,
1150	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1960	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1151	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1961	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1962	Net::SSLeay::CTX_set_mode ($tls, 1|2);
1152		1963
1153	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1964	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1154	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1965	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1155		1966
		1967	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		1968
1156	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1969	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1157		1970
1158	$self->{filter_w} = sub {	1971	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1159	$_[0]{_tls_wbuf} .= ${$_[1]};	1972	if $self->{on_starttls};
1160	&_dotls;	1973
1161	};	1974	&_dotls; # need to trigger the initial handshake
1162	$self->{filter_r} = sub {	1975	$self->start_read; # make sure we actually do read
1163	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1164	&_dotls;
1165	};
1166	}	1976	}
1167		1977
1168	=item $handle->stoptls	1978	=item $handle->stoptls
1169		1979
1170	Destroys the SSL connection, if any. Partial read or write data will be	1980	Shuts down the SSL connection - this makes a proper EOF handshake by
1171	lost.	1981	sending a close notify to the other side, but since OpenSSL doesn't
		1982	support non-blocking shut downs, it is not guaranteed that you can re-use
		1983	the stream afterwards.
		1984
		1985	This method may invoke callbacks (and therefore the handle might be
		1986	destroyed after it returns).
1172		1987
1173	=cut	1988	=cut
1174		1989
1175	sub stoptls {	1990	sub stoptls {
1176	my ($self) = @_;	1991	my ($self) = @_;
1177		1992
1178	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1993	if ($self->{tls} && $self->{fh}) {
		1994	Net::SSLeay::shutdown ($self->{tls});
1179		1995
1180	delete $self->{_rbio};	1996	&_dotls;
1181	delete $self->{_wbio};	1997
1182	delete $self->{_tls_wbuf};	1998	# # we don't give a shit. no, we do, but we can't. no...#d#
1183	delete $self->{filter_r};	1999	# # we, we... have to use openssl :/#d#
1184	delete $self->{filter_w};	2000	# &_freetls;#d#
		2001	}
		2002	}
		2003
		2004	sub _freetls {
		2005	my ($self) = @_;
		2006
		2007	return unless $self->{tls};
		2008
		2009	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2010	if $self->{tls} > 0;
		2011
		2012	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1185	}	2013	}
1186		2014
1187	sub DESTROY {	2015	sub DESTROY {
1188	my $self = shift;	2016	my ($self) = @_;
1189		2017
1190	$self->stoptls;	2018	&_freetls;
		2019
		2020	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		2021
		2022	if ($linger && length $self->{wbuf} && $self->{fh}) {
		2023	my $fh = delete $self->{fh};
		2024	my $wbuf = delete $self->{wbuf};
		2025
		2026	my @linger;
		2027
		2028	push @linger, AE::io $fh, 1, sub {
		2029	my $len = syswrite $fh, $wbuf, length $wbuf;
		2030
		2031	if ($len > 0) {
		2032	substr $wbuf, 0, $len, "";
		2033	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
		2034	@linger = (); # end
		2035	}
		2036	};
		2037	push @linger, AE::timer $linger, 0, sub {
		2038	@linger = ();
		2039	};
		2040	}
1191	}	2041	}
		2042
		2043	=item $handle->destroy
		2044
		2045	Shuts down the handle object as much as possible - this call ensures that
		2046	no further callbacks will be invoked and as many resources as possible
		2047	will be freed. Any method you will call on the handle object after
		2048	destroying it in this way will be silently ignored (and it will return the
		2049	empty list).
		2050
		2051	Normally, you can just "forget" any references to an AnyEvent::Handle
		2052	object and it will simply shut down. This works in fatal error and EOF
		2053	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2054	callback, so when you want to destroy the AnyEvent::Handle object from
		2055	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2056	that case.
		2057
		2058	Destroying the handle object in this way has the advantage that callbacks
		2059	will be removed as well, so if those are the only reference holders (as
		2060	is common), then one doesn't need to do anything special to break any
		2061	reference cycles.
		2062
		2063	The handle might still linger in the background and write out remaining
		2064	data, as specified by the C<linger> option, however.
		2065
		2066	=cut
		2067
		2068	sub destroy {
		2069	my ($self) = @_;
		2070
		2071	$self->DESTROY;
		2072	%$self = ();
		2073	bless $self, "AnyEvent::Handle::destroyed";
		2074	}
		2075
		2076	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2077	#nop
		2078	}
		2079
		2080	=item $handle->destroyed
		2081
		2082	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2083	->destroy >>, true otherwise.
		2084
		2085	Can be useful to decide whether the handle is still valid after some
		2086	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2087	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2088	can destroy the handle, so work can be avoided by checking sometimes:
		2089
		2090	$hdl->starttls ("accept");
		2091	return if $hdl->destroyed;
		2092	$hdl->push_write (...
		2093
		2094	Note that the call to C<push_write> will silently be ignored if the handle
		2095	has been destroyed, so often you can just ignore the possibility of the
		2096	handle being destroyed.
		2097
		2098	=cut
		2099
		2100	sub destroyed { 0 }
		2101	sub AnyEvent::Handle::destroyed::destroyed { 1 }
1192		2102
1193	=item AnyEvent::Handle::TLS_CTX	2103	=item AnyEvent::Handle::TLS_CTX
1194		2104
1195	This function creates and returns the Net::SSLeay::CTX object used by	2105	This function creates and returns the AnyEvent::TLS object used by default
1196	default for TLS mode.	2106	for TLS mode.
1197		2107
1198	The context is created like this:	2108	The context is created by calling L<AnyEvent::TLS> without any arguments.
1199
1200	Net::SSLeay::load_error_strings;
1201	Net::SSLeay::SSLeay_add_ssl_algorithms;
1202	Net::SSLeay::randomize;
1203
1204	my $CTX = Net::SSLeay::CTX_new;
1205
1206	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1207		2109
1208	=cut	2110	=cut
1209		2111
1210	our $TLS_CTX;	2112	our $TLS_CTX;
1211		2113
1212	sub TLS_CTX() {	2114	sub TLS_CTX() {
1213	$TLS_CTX || do {	2115	$TLS_CTX ||= do {
1214	require Net::SSLeay;	2116	require AnyEvent::TLS;
1215		2117
1216	Net::SSLeay::load_error_strings ();	2118	new AnyEvent::TLS
1217	Net::SSLeay::SSLeay_add_ssl_algorithms ();
1218	Net::SSLeay::randomize ();
1219
1220	$TLS_CTX = Net::SSLeay::CTX_new ();
1221
1222	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1223
1224	$TLS_CTX
1225	}	2119	}
1226	}	2120	}
1227		2121
1228	=back	2122	=back
		2123
		2124
		2125	=head1 NONFREQUENTLY ASKED QUESTIONS
		2126
		2127	=over 4
		2128
		2129	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2130	still get further invocations!
		2131
		2132	That's because AnyEvent::Handle keeps a reference to itself when handling
		2133	read or write callbacks.
		2134
		2135	It is only safe to "forget" the reference inside EOF or error callbacks,
		2136	from within all other callbacks, you need to explicitly call the C<<
		2137	->destroy >> method.
		2138
		2139	=item I get different callback invocations in TLS mode/Why can't I pause
		2140	reading?
		2141
		2142	Unlike, say, TCP, TLS connections do not consist of two independent
		2143	communication channels, one for each direction. Or put differently, the
		2144	read and write directions are not independent of each other: you cannot
		2145	write data unless you are also prepared to read, and vice versa.
		2146
		2147	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2148	callback invocations when you are not expecting any read data - the reason
		2149	is that AnyEvent::Handle always reads in TLS mode.
		2150
		2151	During the connection, you have to make sure that you always have a
		2152	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2153	connection (or when you no longer want to use it) you can call the
		2154	C<destroy> method.
		2155
		2156	=item How do I read data until the other side closes the connection?
		2157
		2158	If you just want to read your data into a perl scalar, the easiest way
		2159	to achieve this is by setting an C<on_read> callback that does nothing,
		2160	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2161	will be in C<$_[0]{rbuf}>:
		2162
		2163	$handle->on_read (sub { });
		2164	$handle->on_eof (undef);
		2165	$handle->on_error (sub {
		2166	my $data = delete $_[0]{rbuf};
		2167	});
		2168
		2169	The reason to use C<on_error> is that TCP connections, due to latencies
		2170	and packets loss, might get closed quite violently with an error, when in
		2171	fact all data has been received.
		2172
		2173	It is usually better to use acknowledgements when transferring data,
		2174	to make sure the other side hasn't just died and you got the data
		2175	intact. This is also one reason why so many internet protocols have an
		2176	explicit QUIT command.
		2177
		2178	=item I don't want to destroy the handle too early - how do I wait until
		2179	all data has been written?
		2180
		2181	After writing your last bits of data, set the C<on_drain> callback
		2182	and destroy the handle in there - with the default setting of
		2183	C<low_water_mark> this will be called precisely when all data has been
		2184	written to the socket:
		2185
		2186	$handle->push_write (...);
		2187	$handle->on_drain (sub {
		2188	warn "all data submitted to the kernel\n";
		2189	undef $handle;
		2190	});
		2191
		2192	If you just want to queue some data and then signal EOF to the other side,
		2193	consider using C<< ->push_shutdown >> instead.
		2194
		2195	=item I want to contact a TLS/SSL server, I don't care about security.
		2196
		2197	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2198	connect to it and then create the AnyEvent::Handle with the C<tls>
		2199	parameter:
		2200
		2201	tcp_connect $host, $port, sub {
		2202	my ($fh) = @_;
		2203
		2204	my $handle = new AnyEvent::Handle
		2205	fh => $fh,
		2206	tls => "connect",
		2207	on_error => sub { ... };
		2208
		2209	$handle->push_write (...);
		2210	};
		2211
		2212	=item I want to contact a TLS/SSL server, I do care about security.
		2213
		2214	Then you should additionally enable certificate verification, including
		2215	peername verification, if the protocol you use supports it (see
		2216	L<AnyEvent::TLS>, C<verify_peername>).
		2217
		2218	E.g. for HTTPS:
		2219
		2220	tcp_connect $host, $port, sub {
		2221	my ($fh) = @_;
		2222
		2223	my $handle = new AnyEvent::Handle
		2224	fh => $fh,
		2225	peername => $host,
		2226	tls => "connect",
		2227	tls_ctx => { verify => 1, verify_peername => "https" },
		2228	...
		2229
		2230	Note that you must specify the hostname you connected to (or whatever
		2231	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2232	peername verification will be done.
		2233
		2234	The above will use the system-dependent default set of trusted CA
		2235	certificates. If you want to check against a specific CA, add the
		2236	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2237
		2238	tls_ctx => {
		2239	verify => 1,
		2240	verify_peername => "https",
		2241	ca_file => "my-ca-cert.pem",
		2242	},
		2243
		2244	=item I want to create a TLS/SSL server, how do I do that?
		2245
		2246	Well, you first need to get a server certificate and key. You have
		2247	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2248	self-signed certificate (cheap. check the search engine of your choice,
		2249	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2250	nice program for that purpose).
		2251
		2252	Then create a file with your private key (in PEM format, see
		2253	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2254	file should then look like this:
		2255
		2256	-----BEGIN RSA PRIVATE KEY-----
		2257	...header data
		2258	... lots of base64'y-stuff
		2259	-----END RSA PRIVATE KEY-----
		2260
		2261	-----BEGIN CERTIFICATE-----
		2262	... lots of base64'y-stuff
		2263	-----END CERTIFICATE-----
		2264
		2265	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2266	specify this file as C<cert_file>:
		2267
		2268	tcp_server undef, $port, sub {
		2269	my ($fh) = @_;
		2270
		2271	my $handle = new AnyEvent::Handle
		2272	fh => $fh,
		2273	tls => "accept",
		2274	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2275	...
		2276
		2277	When you have intermediate CA certificates that your clients might not
		2278	know about, just append them to the C<cert_file>.
		2279
		2280	=back
		2281
1229		2282
1230	=head1 SUBCLASSING AnyEvent::Handle	2283	=head1 SUBCLASSING AnyEvent::Handle
1231		2284
1232	In many cases, you might want to subclass AnyEvent::Handle.	2285	In many cases, you might want to subclass AnyEvent::Handle.
1233		2286
…		…
1237	=over 4	2290	=over 4
1238		2291
1239	=item * all constructor arguments become object members.	2292	=item * all constructor arguments become object members.
1240		2293
1241	At least initially, when you pass a C<tls>-argument to the constructor it	2294	At least initially, when you pass a C<tls>-argument to the constructor it
1242	will end up in C<< $handle->{tls} >>. Those members might be changes or	2295	will end up in C<< $handle->{tls} >>. Those members might be changed or
1243	mutated later on (for example C<tls> will hold the TLS connection object).	2296	mutated later on (for example C<tls> will hold the TLS connection object).
1244		2297
1245	=item * other object member names are prefixed with an C<_>.	2298	=item * other object member names are prefixed with an C<_>.
1246		2299
1247	All object members not explicitly documented (internal use) are prefixed	2300	All object members not explicitly documented (internal use) are prefixed
…		…
1250		2303
1251	=item * all members not documented here and not prefixed with an underscore	2304	=item * all members not documented here and not prefixed with an underscore
1252	are free to use in subclasses.	2305	are free to use in subclasses.
1253		2306
1254	Of course, new versions of AnyEvent::Handle may introduce more "public"	2307	Of course, new versions of AnyEvent::Handle may introduce more "public"
1255	member variables, but thats just life, at least it is documented.	2308	member variables, but that's just life. At least it is documented.
1256		2309
1257	=back	2310	=back
1258		2311
1259	=head1 AUTHOR	2312	=head1 AUTHOR
1260		2313

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