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Revision 1.208 by root, Sun Dec 5 11:41:45 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 = 4.14;
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 => $filehandle [C<fh> or C<connect> MANDATORY]
72		93
73	The filehandle this L<AnyEvent::Handle> object will operate on.	94	The filehandle this L<AnyEvent::Handle> object will operate on.
74
75	NOTE: The filehandle will be set to non-blocking (using	95	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		97	that mode.
77		98
		99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
		100
		101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
		104
		105	You have to specify either this parameter, or C<fh>, above.
		106
		107	It is possible to push requests on the read and write queues, and modify
		108	properties of the stream, even while AnyEvent::Handle is connecting.
		109
		110	When this parameter is specified, then the C<on_prepare>,
		111	C<on_connect_error> and C<on_connect> callbacks will be called under the
		112	appropriate circumstances:
		113
		114	=over 4
		115
78	=item on_eof => $cb->($handle)	116	=item on_prepare => $cb->($handle)
79		117
80	Set the callback to be called when an end-of-file condition is detcted,	118	This (rarely used) callback is called before a new connection is
81	i.e. in the case of a socket, when the other side has closed the	119	attempted, but after the file handle has been created. It could be used to
82	connection cleanly.	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).
83		123
84	While not mandatory, it is highly recommended to set an eof callback,	124	The return value of this callback should be the connect timeout value in
85	otherwise you might end up with a closed socket while you are still	125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
86	waiting for data.	126	default timeout is to be used).
87		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
88	=item on_error => $cb->($handle, $fatal)	154	=item on_error => $cb->($handle, $fatal, $message)
89		155
90	This is the error callback, which is called when, well, some error	156	This is the error callback, which is called when, well, some error
91	occured, such as not being able to resolve the hostname, failure to	157	occured, such as not being able to resolve the hostname, failure to
92	connect or a read error.	158	connect, or a read error.
93		159
94	Some errors are fatal (which is indicated by C<$fatal> being true). On	160	Some errors are fatal (which is indicated by C<$fatal> being true). On
95	fatal errors the handle object will be shut down and will not be	161	fatal errors the handle object will be destroyed (by a call to C<< ->
		162	destroy >>) after invoking the error callback (which means you are free to
		163	examine the handle object). Examples of fatal errors are an EOF condition
		164	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		165	cases where the other side can close the connection at will, it is
		166	often easiest to not report C<EPIPE> errors in this callback.
		167
		168	AnyEvent::Handle tries to find an appropriate error code for you to check
		169	against, but in some cases (TLS errors), this does not work well. It is
		170	recommended to always output the C<$message> argument in human-readable
		171	error messages (it's usually the same as C<"$!">).
		172
96	usable. Non-fatal errors can be retried by simply returning, but it is	173	Non-fatal errors can be retried by returning, but it is recommended
97	recommended to simply ignore this parameter and instead abondon the handle	174	to simply ignore this parameter and instead abondon the handle object
98	object when this callback is invoked.	175	when this callback is invoked. Examples of non-fatal errors are timeouts
		176	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99		177
100	On callback entrance, the value of C<$!> contains the operating system	178	On entry to the callback, the value of C<$!> contains the operating
101	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
		180	C<EPROTO>).
102		181
103	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
104	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
105	C<croak>.	184	C<croak>.
106		185
107	=item on_read => $cb->($handle)	186	=item on_read => $cb->($handle)
108		187
109	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
110	and no read request is in the queue (unlike read queue callbacks, this	189	and no read request is in the queue (unlike read queue callbacks, this
111	callback will only be called when at least one octet of data is in the	190	callback will only be called when at least one octet of data is in the
112	read buffer).	191	read buffer).
113		192
114	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 >>
115	method or access the C<$handle->{rbuf}> member directly.	194	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		195	must not enlarge or modify the read buffer, you can only remove data at
		196	the beginning from it.
116		197
		198	You can also call C<< ->push_read (...) >> or any other function that
		199	modifies the read queue. Or do both. Or ...
		200
117	When an EOF condition is detected then AnyEvent::Handle will first try to	201	When an EOF condition is detected, AnyEvent::Handle will first try to
118	feed all the remaining data to the queued callbacks and C<on_read> before	202	feed all the remaining data to the queued callbacks and C<on_read> before
119	calling the C<on_eof> callback. If no progress can be made, then a fatal	203	calling the C<on_eof> callback. If no progress can be made, then a fatal
120	error will be raised (with C<$!> set to C<EPIPE>).	204	error will be raised (with C<$!> set to C<EPIPE>).
121		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
122	=item on_drain => $cb->($handle)	227	=item on_drain => $cb->($handle)
123		228
124	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
125	(or when the callback is set and the buffer is empty already).	230	(or immediately if the buffer is empty already).
126		231
127	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.
128		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
129	=item timeout => $fractional_seconds	240	=item timeout => $fractional_seconds
130		241
		242	=item rtimeout => $fractional_seconds
		243
		244	=item wtimeout => $fractional_seconds
		245
131	If non-zero, then this enables an "inactivity" timeout: whenever this many	246	If non-zero, then these enables an "inactivity" timeout: whenever this
132	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
133	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
134	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).
135		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
136	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
137	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
138	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
139	in the C<on_timeout> callback.	261	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		262	restart the timeout.
140		263
141	Zero (the default) disables this timeout.	264	Zero (the default) disables this timeout.
142		265
143	=item on_timeout => $cb->($handle)	266	=item on_timeout => $cb->($handle)
144		267
…		…
148		271
149	=item rbuf_max => <bytes>	272	=item rbuf_max => <bytes>
150		273
151	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>)
152	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
153	avoid denial-of-service attacks.	276	avoid some forms of denial-of-service attacks.
154		277
155	For example, a server accepting connections from untrusted sources should	278	For example, a server accepting connections from untrusted sources should
156	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
157	(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
158	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
159	isn't finished).	282	isn't finished).
160		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
161	=item read_size => <bytes>	342	=item read_size => <bytes>
162		343
163	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
164	during each (loop iteration). Default: C<8192>.	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.
165		355
166	=item low_water_mark => <bytes>	356	=item low_water_mark => <bytes>
167		357
168	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
169	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
170	considered empty.	360	considered empty.
171		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
172	=item linger => <seconds>	367	=item linger => <seconds>
173		368
174	If non-zero (default: C<3600>), then the destructor of the	369	If this is non-zero (default: C<3600>), the destructor of the
175	AnyEvent::Handle object will check wether there is still outstanding write	370	AnyEvent::Handle object will check whether there is still outstanding
176	data and will install a watcher that will write out this data. No errors	371	write data and will install a watcher that will write this data to the
177	will be reported (this mostly matches how the operating system treats	372	socket. No errors will be reported (this mostly matches how the operating
178	outstanding data at socket close time).	373	system treats outstanding data at socket close time).
179		374
180	This will not work for partial TLS data that could not yet been	375	This will not work for partial TLS data that could not be encoded
181	encoded. This data will be lost.	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>.
182		388
183	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	389	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
184		390
185	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
186	will start making tls handshake and will transparently encrypt/decrypt	392	AnyEvent will start a TLS handshake as soon as the connection has been
187	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.
188		397
189	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
190	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.
191		402
192	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
193	connection, use C<connect> mode.	404	C<accept>, and for the TLS client side of a connection, use C<connect>
		405	mode.
194		406
195	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
196	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>
197	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
198	AnyEvent::Handle.	410	AnyEvent::Handle. Also, this module will take ownership of this connection
		411	object.
199		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
200	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.
201		423
202	=item tls_ctx => $ssl_ctx	424	=item tls_ctx => $anyevent_tls
203		425
204	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
205	(unless a connection object was specified directly). If this parameter is	427	(unless a connection object was specified directly). If this
206	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	428	parameter is missing (or C<undef>), then AnyEvent::Handle will use
		429	C<AnyEvent::Handle::TLS_CTX>.
		430
		431	Instead of an object, you can also specify a hash reference with C<< key
		432	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		433	new TLS context object.
		434
		435	=item on_starttls => $cb->($handle, $success[, $error_message])
		436
		437	This callback will be invoked when the TLS/SSL handshake has finished. If
		438	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		439	(C<on_stoptls> will not be called in this case).
		440
		441	The session in C<< $handle->{tls} >> can still be examined in this
		442	callback, even when the handshake was not successful.
		443
		444	TLS handshake failures will not cause C<on_error> to be invoked when this
		445	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		446
		447	Without this callback, handshake failures lead to C<on_error> being
		448	called as usual.
		449
		450	Note that you cannot just call C<starttls> again in this callback. If you
		451	need to do that, start an zero-second timer instead whose callback can
		452	then call C<< ->starttls >> again.
		453
		454	=item on_stoptls => $cb->($handle)
		455
		456	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		457	set, then it will be invoked after freeing the TLS session. If it is not,
		458	then a TLS shutdown condition will be treated like a normal EOF condition
		459	on the handle.
		460
		461	The session in C<< $handle->{tls} >> can still be examined in this
		462	callback.
		463
		464	This callback will only be called on TLS shutdowns, not when the
		465	underlying handle signals EOF.
207		466
208	=item json => JSON or JSON::XS object	467	=item json => JSON or JSON::XS object
209		468
210	This is the json coder object used by the C<json> read and write types.	469	This is the json coder object used by the C<json> read and write types.
211		470
212	If you don't supply it, then AnyEvent::Handle will create and use a	471	If you don't supply it, then AnyEvent::Handle will create and use a
213	suitable one, which will write and expect UTF-8 encoded JSON texts.	472	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		473	texts.
214		474
215	Note that you are responsible to depend on the JSON module if you want to	475	Note that you are responsible to depend on the JSON module if you want to
216	use this functionality, as AnyEvent does not have a dependency itself.	476	use this functionality, as AnyEvent does not have a dependency itself.
217		477
218	=item filter_r => $cb
219
220	=item filter_w => $cb
221
222	These exist, but are undocumented at this time.
223
224	=back	478	=back
225		479
226	=cut	480	=cut
227		481
228	sub new {	482	sub new {
229	my $class = shift;	483	my $class = shift;
230
231	my $self = bless { @_ }, $class;	484	my $self = bless { @_ }, $class;
232		485
233	$self->{fh} or Carp::croak "mandatory argument fh is missing";	486	if ($self->{fh}) {
		487	$self->_start;
		488	return unless $self->{fh}; # could be gone by now
		489
		490	} elsif ($self->{connect}) {
		491	require AnyEvent::Socket;
		492
		493	$self->{peername} = $self->{connect}[0]
		494	unless exists $self->{peername};
		495
		496	$self->{_skip_drain_rbuf} = 1;
		497
		498	{
		499	Scalar::Util::weaken (my $self = $self);
		500
		501	$self->{_connect} =
		502	AnyEvent::Socket::tcp_connect (
		503	$self->{connect}[0],
		504	$self->{connect}[1],
		505	sub {
		506	my ($fh, $host, $port, $retry) = @_;
		507
		508	delete $self->{_connect}; # no longer needed
		509
		510	if ($fh) {
		511	$self->{fh} = $fh;
		512
		513	delete $self->{_skip_drain_rbuf};
		514	$self->_start;
		515
		516	$self->{on_connect}
		517	and $self->{on_connect}($self, $host, $port, sub {
		518	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		519	$self->{_skip_drain_rbuf} = 1;
		520	&$retry;
		521	});
		522
		523	} else {
		524	if ($self->{on_connect_error}) {
		525	$self->{on_connect_error}($self, "$!");
		526	$self->destroy;
		527	} else {
		528	$self->_error ($!, 1);
		529	}
		530	}
		531	},
		532	sub {
		533	local $self->{fh} = $_[0];
		534
		535	$self->{on_prepare}
		536	? $self->{on_prepare}->($self)
		537	: ()
		538	}
		539	);
		540	}
		541
		542	} else {
		543	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		544	}
		545
		546	$self
		547	}
		548
		549	sub _start {
		550	my ($self) = @_;
		551
		552	# too many clueless people try to use udp and similar sockets
		553	# with AnyEvent::Handle, do them a favour.
		554	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		555	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		556	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
234		557
235	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	558	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
236		559
237	if ($self->{tls}) {	560	$self->{_activity} =
238	require Net::SSLeay;	561	$self->{_ractivity} =
		562	$self->{_wactivity} = AE::now;
		563
		564	$self->{read_size} ||= 2048;
		565	$self->{max_read_size} = $self->{read_size}
		566	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		567
		568	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		569	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		570	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		571
		572	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		573	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		574
		575	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		576
239	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	577	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
240	}	578	if $self->{tls};
241		579
242	$self->{_activity} = AnyEvent->now;
243	$self->_timeout;
244
245	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	580	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
246		581
247	$self	582	$self->start_read
248	}	583	if $self->{on_read} || @{ $self->{_queue} };
249		584
250	sub _shutdown {	585	$self->_drain_wbuf;
251	my ($self) = @_;
252
253	delete $self->{_tw};
254	delete $self->{_rw};
255	delete $self->{_ww};
256	delete $self->{fh};
257
258	$self->stoptls;
259	}	586	}
260		587
261	sub _error {	588	sub _error {
262	my ($self, $errno, $fatal) = @_;	589	my ($self, $errno, $fatal, $message) = @_;
263
264	$self->_shutdown
265	if $fatal;
266		590
267	$! = $errno;	591	$! = $errno;
		592	$message ||= "$!";
268		593
269	if ($self->{on_error}) {	594	if ($self->{on_error}) {
270	$self->{on_error}($self, $fatal);	595	$self->{on_error}($self, $fatal, $message);
271	} else {	596	$self->destroy if $fatal;
		597	} elsif ($self->{fh} || $self->{connect}) {
		598	$self->destroy;
272	Carp::croak "AnyEvent::Handle uncaught error: $!";	599	Carp::croak "AnyEvent::Handle uncaught error: $message";
273	}	600	}
274	}	601	}
275		602
276	=item $fh = $handle->fh	603	=item $fh = $handle->fh
277		604
278	This method returns the file handle of the L<AnyEvent::Handle> object.	605	This method returns the file handle used to create the L<AnyEvent::Handle> object.
279		606
280	=cut	607	=cut
281		608
282	sub fh { $_[0]{fh} }	609	sub fh { $_[0]{fh} }
283		610
…		…
301	$_[0]{on_eof} = $_[1];	628	$_[0]{on_eof} = $_[1];
302	}	629	}
303		630
304	=item $handle->on_timeout ($cb)	631	=item $handle->on_timeout ($cb)
305		632
306	Replace the current C<on_timeout> callback, or disables the callback	633	=item $handle->on_rtimeout ($cb)
307	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
308	argument.
309		634
310	=cut	635	=item $handle->on_wtimeout ($cb)
311		636
		637	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		638	callback, or disables the callback (but not the timeout) if C<$cb> =
		639	C<undef>. See the C<timeout> constructor argument and method.
		640
		641	=cut
		642
		643	# see below
		644
		645	=item $handle->autocork ($boolean)
		646
		647	Enables or disables the current autocork behaviour (see C<autocork>
		648	constructor argument). Changes will only take effect on the next write.
		649
		650	=cut
		651
		652	sub autocork {
		653	$_[0]{autocork} = $_[1];
		654	}
		655
		656	=item $handle->no_delay ($boolean)
		657
		658	Enables or disables the C<no_delay> setting (see constructor argument of
		659	the same name for details).
		660
		661	=cut
		662
		663	sub no_delay {
		664	$_[0]{no_delay} = $_[1];
		665
		666	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		667	if $_[0]{fh};
		668	}
		669
		670	=item $handle->keepalive ($boolean)
		671
		672	Enables or disables the C<keepalive> setting (see constructor argument of
		673	the same name for details).
		674
		675	=cut
		676
		677	sub keepalive {
		678	$_[0]{keepalive} = $_[1];
		679
		680	eval {
		681	local $SIG{__DIE__};
		682	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		683	if $_[0]{fh};
		684	};
		685	}
		686
		687	=item $handle->oobinline ($boolean)
		688
		689	Enables or disables the C<oobinline> setting (see constructor argument of
		690	the same name for details).
		691
		692	=cut
		693
		694	sub oobinline {
		695	$_[0]{oobinline} = $_[1];
		696
		697	eval {
		698	local $SIG{__DIE__};
		699	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		700	if $_[0]{fh};
		701	};
		702	}
		703
		704	=item $handle->keepalive ($boolean)
		705
		706	Enables or disables the C<keepalive> setting (see constructor argument of
		707	the same name for details).
		708
		709	=cut
		710
		711	sub keepalive {
		712	$_[0]{keepalive} = $_[1];
		713
		714	eval {
		715	local $SIG{__DIE__};
		716	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		717	if $_[0]{fh};
		718	};
		719	}
		720
		721	=item $handle->on_starttls ($cb)
		722
		723	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		724
		725	=cut
		726
		727	sub on_starttls {
		728	$_[0]{on_starttls} = $_[1];
		729	}
		730
		731	=item $handle->on_stoptls ($cb)
		732
		733	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		734
		735	=cut
		736
312	sub on_timeout {	737	sub on_stoptls {
313	$_[0]{on_timeout} = $_[1];	738	$_[0]{on_stoptls} = $_[1];
		739	}
		740
		741	=item $handle->rbuf_max ($max_octets)
		742
		743	Configures the C<rbuf_max> setting (C<undef> disables it).
		744
		745	=cut
		746
		747	sub rbuf_max {
		748	$_[0]{rbuf_max} = $_[1];
314	}	749	}
315		750
316	#############################################################################	751	#############################################################################
317		752
318	=item $handle->timeout ($seconds)	753	=item $handle->timeout ($seconds)
319		754
		755	=item $handle->rtimeout ($seconds)
		756
		757	=item $handle->wtimeout ($seconds)
		758
320	Configures (or disables) the inactivity timeout.	759	Configures (or disables) the inactivity timeout.
321		760
322	=cut	761	=item $handle->timeout_reset
323		762
324	sub timeout {	763	=item $handle->rtimeout_reset
		764
		765	=item $handle->wtimeout_reset
		766
		767	Reset the activity timeout, as if data was received or sent.
		768
		769	These methods are cheap to call.
		770
		771	=cut
		772
		773	for my $dir ("", "r", "w") {
		774	my $timeout = "${dir}timeout";
		775	my $tw = "_${dir}tw";
		776	my $on_timeout = "on_${dir}timeout";
		777	my $activity = "_${dir}activity";
		778	my $cb;
		779
		780	*$on_timeout = sub {
		781	$_[0]{$on_timeout} = $_[1];
		782	};
		783
		784	*$timeout = sub {
325	my ($self, $timeout) = @_;	785	my ($self, $new_value) = @_;
326		786
		787	$new_value >= 0
		788	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		789
327	$self->{timeout} = $timeout;	790	$self->{$timeout} = $new_value;
328	$self->_timeout;	791	delete $self->{$tw}; &$cb;
329	}	792	};
330		793
		794	*{"${dir}timeout_reset"} = sub {
		795	$_[0]{$activity} = AE::now;
		796	};
		797
		798	# main workhorse:
331	# reset the timeout watcher, as neccessary	799	# reset the timeout watcher, as neccessary
332	# also check for time-outs	800	# also check for time-outs
333	sub _timeout {	801	$cb = sub {
334	my ($self) = @_;	802	my ($self) = @_;
335		803
336	if ($self->{timeout}) {	804	if ($self->{$timeout} && $self->{fh}) {
337	my $NOW = AnyEvent->now;	805	my $NOW = AE::now;
338		806
339	# when would the timeout trigger?	807	# when would the timeout trigger?
340	my $after = $self->{_activity} + $self->{timeout} - $NOW;	808	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
341		809
342	# now or in the past already?	810	# now or in the past already?
343	if ($after <= 0) {	811	if ($after <= 0) {
344	$self->{_activity} = $NOW;	812	$self->{$activity} = $NOW;
345		813
346	if ($self->{on_timeout}) {	814	if ($self->{$on_timeout}) {
347	$self->{on_timeout}($self);	815	$self->{$on_timeout}($self);
348	} else {	816	} else {
349	$self->_error (&Errno::ETIMEDOUT);	817	$self->_error (Errno::ETIMEDOUT);
		818	}
		819
		820	# callback could have changed timeout value, optimise
		821	return unless $self->{$timeout};
		822
		823	# calculate new after
		824	$after = $self->{$timeout};
350	}	825	}
351		826
352	# callback could have changed timeout value, optimise	827	Scalar::Util::weaken $self;
353	return unless $self->{timeout};	828	return unless $self; # ->error could have destroyed $self
354		829
355	# calculate new after	830	$self->{$tw} ||= AE::timer $after, 0, sub {
356	$after = $self->{timeout};	831	delete $self->{$tw};
		832	$cb->($self);
		833	};
		834	} else {
		835	delete $self->{$tw};
357	}	836	}
358
359	Scalar::Util::weaken $self;
360	return unless $self; # ->error could have destroyed $self
361
362	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
363	delete $self->{_tw};
364	$self->_timeout;
365	});
366	} else {
367	delete $self->{_tw};
368	}	837	}
369	}	838	}
370		839
371	#############################################################################	840	#############################################################################
372		841
…		…
388	=item $handle->on_drain ($cb)	857	=item $handle->on_drain ($cb)
389		858
390	Sets the C<on_drain> callback or clears it (see the description of	859	Sets the C<on_drain> callback or clears it (see the description of
391	C<on_drain> in the constructor).	860	C<on_drain> in the constructor).
392		861
		862	This method may invoke callbacks (and therefore the handle might be
		863	destroyed after it returns).
		864
393	=cut	865	=cut
394		866
395	sub on_drain {	867	sub on_drain {
396	my ($self, $cb) = @_;	868	my ($self, $cb) = @_;
397		869
398	$self->{on_drain} = $cb;	870	$self->{on_drain} = $cb;
399		871
400	$cb->($self)	872	$cb->($self)
401	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	873	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
402	}	874	}
403		875
404	=item $handle->push_write ($data)	876	=item $handle->push_write ($data)
405		877
406	Queues the given scalar to be written. You can push as much data as you	878	Queues the given scalar to be written. You can push as much data as you
407	want (only limited by the available memory), as C<AnyEvent::Handle>	879	want (only limited by the available memory), as C<AnyEvent::Handle>
408	buffers it independently of the kernel.	880	buffers it independently of the kernel.
409		881
		882	This method may invoke callbacks (and therefore the handle might be
		883	destroyed after it returns).
		884
410	=cut	885	=cut
411		886
412	sub _drain_wbuf {	887	sub _drain_wbuf {
413	my ($self) = @_;	888	my ($self) = @_;
414		889
…		…
417	Scalar::Util::weaken $self;	892	Scalar::Util::weaken $self;
418		893
419	my $cb = sub {	894	my $cb = sub {
420	my $len = syswrite $self->{fh}, $self->{wbuf};	895	my $len = syswrite $self->{fh}, $self->{wbuf};
421		896
422	if ($len >= 0) {	897	if (defined $len) {
423	substr $self->{wbuf}, 0, $len, "";	898	substr $self->{wbuf}, 0, $len, "";
424		899
425	$self->{_activity} = AnyEvent->now;	900	$self->{_activity} = $self->{_wactivity} = AE::now;
426		901
427	$self->{on_drain}($self)	902	$self->{on_drain}($self)
428	if $self->{low_water_mark} >= length $self->{wbuf}	903	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
429	&& $self->{on_drain};	904	&& $self->{on_drain};
430		905
431	delete $self->{_ww} unless length $self->{wbuf};	906	delete $self->{_ww} unless length $self->{wbuf};
432	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	907	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
433	$self->_error ($!, 1);	908	$self->_error ($!, 1);
434	}	909	}
435	};	910	};
436		911
437	# try to write data immediately	912	# try to write data immediately
438	$cb->();	913	$cb->() unless $self->{autocork};
439		914
440	# if still data left in wbuf, we need to poll	915	# if still data left in wbuf, we need to poll
441	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	916	$self->{_ww} = AE::io $self->{fh}, 1, $cb
442	if length $self->{wbuf};	917	if length $self->{wbuf};
443	};	918	};
444	}	919	}
445		920
446	our %WH;	921	our %WH;
447		922
		923	# deprecated
448	sub register_write_type($$) {	924	sub register_write_type($$) {
449	$WH{$_[0]} = $_[1];	925	$WH{$_[0]} = $_[1];
450	}	926	}
451		927
452	sub push_write {	928	sub push_write {
453	my $self = shift;	929	my $self = shift;
454		930
455	if (@_ > 1) {	931	if (@_ > 1) {
456	my $type = shift;	932	my $type = shift;
457		933
		934	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
458	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	935	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
459	->($self, @_);	936	->($self, @_);
460	}	937	}
461		938
		939	# we downgrade here to avoid hard-to-track-down bugs,
		940	# and diagnose the problem earlier and better.
		941
462	if ($self->{filter_w}) {	942	if ($self->{tls}) {
463	$self->{filter_w}($self, \$_[0]);	943	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		944	&_dotls ($self) if $self->{fh};
464	} else {	945	} else {
465	$self->{wbuf} .= $_[0];	946	utf8::downgrade $self->{wbuf} .= $_[0];
466	$self->_drain_wbuf;	947	$self->_drain_wbuf if $self->{fh};
467	}	948	}
468	}	949	}
469		950
470	=item $handle->push_write (type => @args)	951	=item $handle->push_write (type => @args)
471		952
472	Instead of formatting your data yourself, you can also let this module do	953	Instead of formatting your data yourself, you can also let this module
473	the job by specifying a type and type-specific arguments.	954	do the job by specifying a type and type-specific arguments. You
		955	can also specify the (fully qualified) name of a package, in which
		956	case AnyEvent tries to load the package and then expects to find the
		957	C<anyevent_write_type> function inside (see "custom write types", below).
474		958
475	Predefined types are (if you have ideas for additional types, feel free to	959	Predefined types are (if you have ideas for additional types, feel free to
476	drop by and tell us):	960	drop by and tell us):
477		961
478	=over 4	962	=over 4
…		…
485	=cut	969	=cut
486		970
487	register_write_type netstring => sub {	971	register_write_type netstring => sub {
488	my ($self, $string) = @_;	972	my ($self, $string) = @_;
489		973
490	sprintf "%d:%s,", (length $string), $string	974	(length $string) . ":$string,"
491	};	975	};
492		976
493	=item packstring => $format, $data	977	=item packstring => $format, $data
494		978
495	An octet string prefixed with an encoded length. The encoding C<$format>	979	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
500	=cut	984	=cut
501		985
502	register_write_type packstring => sub {	986	register_write_type packstring => sub {
503	my ($self, $format, $string) = @_;	987	my ($self, $format, $string) = @_;
504		988
505	pack "$format/a", $string	989	pack "$format/a*", $string
506	};	990	};
507		991
508	=item json => $array_or_hashref	992	=item json => $array_or_hashref
509		993
510	Encodes the given hash or array reference into a JSON object. Unless you	994	Encodes the given hash or array reference into a JSON object. Unless you
…		…
535	Other languages could read single lines terminated by a newline and pass	1019	Other languages could read single lines terminated by a newline and pass
536	this line into their JSON decoder of choice.	1020	this line into their JSON decoder of choice.
537		1021
538	=cut	1022	=cut
539		1023
		1024	sub json_coder() {
		1025	eval { require JSON::XS; JSON::XS->new->utf8 }
		1026	|| do { require JSON; JSON->new->utf8 }
		1027	}
		1028
540	register_write_type json => sub {	1029	register_write_type json => sub {
541	my ($self, $ref) = @_;	1030	my ($self, $ref) = @_;
542		1031
543	require JSON;	1032	my $json = $self->{json} ||= json_coder;
544		1033
545	$self->{json} ? $self->{json}->encode ($ref)	1034	$json->encode ($ref)
546	: JSON::encode_json ($ref)
547	};	1035	};
548		1036
		1037	=item storable => $reference
		1038
		1039	Freezes the given reference using L<Storable> and writes it to the
		1040	handle. Uses the C<nfreeze> format.
		1041
		1042	=cut
		1043
		1044	register_write_type storable => sub {
		1045	my ($self, $ref) = @_;
		1046
		1047	require Storable;
		1048
		1049	pack "w/a*", Storable::nfreeze ($ref)
		1050	};
		1051
549	=back	1052	=back
550		1053
551	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)	1054	=item $handle->push_shutdown
552		1055
553	This function (not method) lets you add your own types to C<push_write>.	1056	Sometimes you know you want to close the socket after writing your data
		1057	before it was actually written. One way to do that is to replace your
		1058	C<on_drain> handler by a callback that shuts down the socket (and set
		1059	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1060	replaces the C<on_drain> callback with:
		1061
		1062	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		1063
		1064	This simply shuts down the write side and signals an EOF condition to the
		1065	the peer.
		1066
		1067	You can rely on the normal read queue and C<on_eof> handling
		1068	afterwards. This is the cleanest way to close a connection.
		1069
		1070	This method may invoke callbacks (and therefore the handle might be
		1071	destroyed after it returns).
		1072
		1073	=cut
		1074
		1075	sub push_shutdown {
		1076	my ($self) = @_;
		1077
		1078	delete $self->{low_water_mark};
		1079	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1080	}
		1081
		1082	=item custom write types - Package::anyevent_write_type $handle, @args
		1083
		1084	Instead of one of the predefined types, you can also specify the name of
		1085	a package. AnyEvent will try to load the package and then expects to find
		1086	a function named C<anyevent_write_type> inside. If it isn't found, it
		1087	progressively tries to load the parent package until it either finds the
		1088	function (good) or runs out of packages (bad).
		1089
554	Whenever the given C<type> is used, C<push_write> will invoke the code	1090	Whenever the given C<type> is used, C<push_write> will the function with
555	reference with the handle object and the remaining arguments.	1091	the handle object and the remaining arguments.
556		1092
557	The code reference is supposed to return a single octet string that will	1093	The function is supposed to return a single octet string that will be
558	be appended to the write buffer.	1094	appended to the write buffer, so you cna mentally treat this function as a
		1095	"arguments to on-the-wire-format" converter.
559		1096
560	Note that this is a function, and all types registered this way will be	1097	Example: implement a custom write type C<join> that joins the remaining
561	global, so try to use unique names.	1098	arguments using the first one.
		1099
		1100	$handle->push_write (My::Type => " ", 1,2,3);
		1101
		1102	# uses the following package, which can be defined in the "My::Type" or in
		1103	# the "My" modules to be auto-loaded, or just about anywhere when the
		1104	# My::Type::anyevent_write_type is defined before invoking it.
		1105
		1106	package My::Type;
		1107
		1108	sub anyevent_write_type {
		1109	my ($handle, $delim, @args) = @_;
		1110
		1111	join $delim, @args
		1112	}
562		1113
563	=cut	1114	=cut
564		1115
565	#############################################################################	1116	#############################################################################
566		1117
…		…
575	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1126	ways, the "simple" way, using only C<on_read> and the "complex" way, using
576	a queue.	1127	a queue.
577		1128
578	In the simple case, you just install an C<on_read> callback and whenever	1129	In the simple case, you just install an C<on_read> callback and whenever
579	new data arrives, it will be called. You can then remove some data (if	1130	new data arrives, it will be called. You can then remove some data (if
580	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	1131	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
581	or not.	1132	leave the data there if you want to accumulate more (e.g. when only a
		1133	partial message has been received so far), or change the read queue with
		1134	e.g. C<push_read>.
582		1135
583	In the more complex case, you want to queue multiple callbacks. In this	1136	In the more complex case, you want to queue multiple callbacks. In this
584	case, AnyEvent::Handle will call the first queued callback each time new	1137	case, AnyEvent::Handle will call the first queued callback each time new
585	data arrives (also the first time it is queued) and removes it when it has	1138	data arrives (also the first time it is queued) and remove it when it has
586	done its job (see C<push_read>, below).	1139	done its job (see C<push_read>, below).
587		1140
588	This way you can, for example, push three line-reads, followed by reading	1141	This way you can, for example, push three line-reads, followed by reading
589	a chunk of data, and AnyEvent::Handle will execute them in order.	1142	a chunk of data, and AnyEvent::Handle will execute them in order.
590		1143
…		…
604	# handle xml	1157	# handle xml
605	});	1158	});
606	});	1159	});
607	});	1160	});
608		1161
609	Example 2: Implement a client for a protocol that replies either with	1162	Example 2: Implement a client for a protocol that replies either with "OK"
610	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1163	and another line or "ERROR" for the first request that is sent, and 64
611	second request. Due tot he availability of a full queue, we can just	1164	bytes for the second request. Due to the availability of a queue, we can
612	pipeline sending both requests and manipulate the queue as necessary in	1165	just pipeline sending both requests and manipulate the queue as necessary
613	the callbacks:	1166	in the callbacks.
614		1167
615	# request one	1168	When the first callback is called and sees an "OK" response, it will
		1169	C<unshift> another line-read. This line-read will be queued I<before> the
		1170	64-byte chunk callback.
		1171
		1172	# request one, returns either "OK + extra line" or "ERROR"
616	$handle->push_write ("request 1\015\012");	1173	$handle->push_write ("request 1\015\012");
617		1174
618	# we expect "ERROR" or "OK" as response, so push a line read	1175	# we expect "ERROR" or "OK" as response, so push a line read
619	$handle->push_read (line => sub {	1176	$handle->push_read (line => sub {
620	# if we got an "OK", we have to _prepend_ another line,	1177	# if we got an "OK", we have to _prepend_ another line,
…		…
627	...	1184	...
628	});	1185	});
629	}	1186	}
630	});	1187	});
631		1188
632	# request two	1189	# request two, simply returns 64 octets
633	$handle->push_write ("request 2\015\012");	1190	$handle->push_write ("request 2\015\012");
634		1191
635	# simply read 64 bytes, always	1192	# simply read 64 bytes, always
636	$handle->push_read (chunk => 64, sub {	1193	$handle->push_read (chunk => 64, sub {
637	my $response = $_[1];	1194	my $response = $_[1];
…		…
643	=cut	1200	=cut
644		1201
645	sub _drain_rbuf {	1202	sub _drain_rbuf {
646	my ($self) = @_;	1203	my ($self) = @_;
647		1204
		1205	# avoid recursion
		1206	return if $self->{_skip_drain_rbuf};
648	local $self->{_in_drain} = 1;	1207	local $self->{_skip_drain_rbuf} = 1;
649
650	if (
651	defined $self->{rbuf_max}
652	&& $self->{rbuf_max} < length $self->{rbuf}
653	) {
654	return $self->_error (&Errno::ENOSPC, 1);
655	}
656		1208
657	while () {	1209	while () {
658	no strict 'refs';	1210	# we need to use a separate tls read buffer, as we must not receive data while
		1211	# we are draining the buffer, and this can only happen with TLS.
		1212	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1213	if exists $self->{_tls_rbuf};
659		1214
660	my $len = length $self->{rbuf};	1215	my $len = length $self->{rbuf};
661		1216
662	if (my $cb = shift @{ $self->{_queue} }) {	1217	if (my $cb = shift @{ $self->{_queue} }) {
663	unless ($cb->($self)) {	1218	unless ($cb->($self)) {
664	if ($self->{_eof}) {	1219	# no progress can be made
665	# no progress can be made (not enough data and no data forthcoming)	1220	# (not enough data and no data forthcoming)
666	$self->_error (&Errno::EPIPE, 1), last;	1221	$self->_error (Errno::EPIPE, 1), return
667	}	1222	if $self->{_eof};
668		1223
669	unshift @{ $self->{_queue} }, $cb;	1224	unshift @{ $self->{_queue} }, $cb;
670	last;	1225	last;
671	}	1226	}
672	} elsif ($self->{on_read}) {	1227	} elsif ($self->{on_read}) {
…		…
679	&& !@{ $self->{_queue} } # and the queue is still empty	1234	&& !@{ $self->{_queue} } # and the queue is still empty
680	&& $self->{on_read} # but we still have on_read	1235	&& $self->{on_read} # but we still have on_read
681	) {	1236	) {
682	# no further data will arrive	1237	# no further data will arrive
683	# so no progress can be made	1238	# so no progress can be made
684	$self->_error (&Errno::EPIPE, 1), last	1239	$self->_error (Errno::EPIPE, 1), return
685	if $self->{_eof};	1240	if $self->{_eof};
686		1241
687	last; # more data might arrive	1242	last; # more data might arrive
688	}	1243	}
689	} else {	1244	} else {
690	# read side becomes idle	1245	# read side becomes idle
691	delete $self->{_rw};	1246	delete $self->{_rw} unless $self->{tls};
692	last;	1247	last;
693	}	1248	}
694	}	1249	}
695		1250
		1251	if ($self->{_eof}) {
		1252	$self->{on_eof}
696	$self->{on_eof}($self)	1253	? $self->{on_eof}($self)
697	if $self->{_eof} && $self->{on_eof};	1254	: $self->_error (0, 1, "Unexpected end-of-file");
		1255
		1256	return;
		1257	}
		1258
		1259	if (
		1260	defined $self->{rbuf_max}
		1261	&& $self->{rbuf_max} < length $self->{rbuf}
		1262	) {
		1263	$self->_error (Errno::ENOSPC, 1), return;
		1264	}
698		1265
699	# may need to restart read watcher	1266	# may need to restart read watcher
700	unless ($self->{_rw}) {	1267	unless ($self->{_rw}) {
701	$self->start_read	1268	$self->start_read
702	if $self->{on_read} || @{ $self->{_queue} };	1269	if $self->{on_read} || @{ $self->{_queue} };
…		…
707		1274
708	This replaces the currently set C<on_read> callback, or clears it (when	1275	This replaces the currently set C<on_read> callback, or clears it (when
709	the new callback is C<undef>). See the description of C<on_read> in the	1276	the new callback is C<undef>). See the description of C<on_read> in the
710	constructor.	1277	constructor.
711		1278
		1279	This method may invoke callbacks (and therefore the handle might be
		1280	destroyed after it returns).
		1281
712	=cut	1282	=cut
713		1283
714	sub on_read {	1284	sub on_read {
715	my ($self, $cb) = @_;	1285	my ($self, $cb) = @_;
716		1286
717	$self->{on_read} = $cb;	1287	$self->{on_read} = $cb;
718	$self->_drain_rbuf if $cb && !$self->{_in_drain};	1288	$self->_drain_rbuf if $cb;
719	}	1289	}
720		1290
721	=item $handle->rbuf	1291	=item $handle->rbuf
722		1292
723	Returns the read buffer (as a modifiable lvalue).	1293	Returns the read buffer (as a modifiable lvalue). You can also access the
		1294	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1295	much faster, and no less clean).
724		1296
725	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1297	The only operation allowed on the read buffer (apart from looking at it)
726	you want.	1298	is removing data from its beginning. Otherwise modifying or appending to
		1299	it is not allowed and will lead to hard-to-track-down bugs.
727		1300
728	NOTE: The read buffer should only be used or modified if the C<on_read>,	1301	NOTE: The read buffer should only be used or modified in the C<on_read>
729	C<push_read> or C<unshift_read> methods are used. The other read methods	1302	callback or when C<push_read> or C<unshift_read> are used with a single
730	automatically manage the read buffer.	1303	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1304	will manage the read buffer on their own.
731		1305
732	=cut	1306	=cut
733		1307
734	sub rbuf : lvalue {	1308	sub rbuf : lvalue {
735	$_[0]{rbuf}	1309	$_[0]{rbuf}
…		…
752		1326
753	If enough data was available, then the callback must remove all data it is	1327	If enough data was available, then the callback must remove all data it is
754	interested in (which can be none at all) and return a true value. After returning	1328	interested in (which can be none at all) and return a true value. After returning
755	true, it will be removed from the queue.	1329	true, it will be removed from the queue.
756		1330
		1331	These methods may invoke callbacks (and therefore the handle might be
		1332	destroyed after it returns).
		1333
757	=cut	1334	=cut
758		1335
759	our %RH;	1336	our %RH;
760		1337
761	sub register_read_type($$) {	1338	sub register_read_type($$) {
…		…
767	my $cb = pop;	1344	my $cb = pop;
768		1345
769	if (@_) {	1346	if (@_) {
770	my $type = shift;	1347	my $type = shift;
771		1348
		1349	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
772	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	1350	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
773	->($self, $cb, @_);	1351	->($self, $cb, @_);
774	}	1352	}
775		1353
776	push @{ $self->{_queue} }, $cb;	1354	push @{ $self->{_queue} }, $cb;
777	$self->_drain_rbuf unless $self->{_in_drain};	1355	$self->_drain_rbuf;
778	}	1356	}
779		1357
780	sub unshift_read {	1358	sub unshift_read {
781	my $self = shift;	1359	my $self = shift;
782	my $cb = pop;	1360	my $cb = pop;
783		1361
784	if (@_) {	1362	if (@_) {
785	my $type = shift;	1363	my $type = shift;
786		1364
		1365	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
787	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")	1366	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
788	->($self, $cb, @_);	1367	->($self, $cb, @_);
789	}	1368	}
790		1369
791
792	unshift @{ $self->{_queue} }, $cb;	1370	unshift @{ $self->{_queue} }, $cb;
793	$self->_drain_rbuf unless $self->{_in_drain};	1371	$self->_drain_rbuf;
794	}	1372	}
795		1373
796	=item $handle->push_read (type => @args, $cb)	1374	=item $handle->push_read (type => @args, $cb)
797		1375
798	=item $handle->unshift_read (type => @args, $cb)	1376	=item $handle->unshift_read (type => @args, $cb)
799		1377
800	Instead of providing a callback that parses the data itself you can chose	1378	Instead of providing a callback that parses the data itself you can chose
801	between a number of predefined parsing formats, for chunks of data, lines	1379	between a number of predefined parsing formats, for chunks of data, lines
802	etc.	1380	etc. You can also specify the (fully qualified) name of a package, in
		1381	which case AnyEvent tries to load the package and then expects to find the
		1382	C<anyevent_read_type> function inside (see "custom read types", below).
803		1383
804	Predefined types are (if you have ideas for additional types, feel free to	1384	Predefined types are (if you have ideas for additional types, feel free to
805	drop by and tell us):	1385	drop by and tell us):
806		1386
807	=over 4	1387	=over 4
…		…
828	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1408	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
829	1	1409	1
830	}	1410	}
831	};	1411	};
832		1412
833	# compatibility with older API
834	sub push_read_chunk {
835	$_[0]->push_read (chunk => $_[1], $_[2]);
836	}
837
838	sub unshift_read_chunk {
839	$_[0]->unshift_read (chunk => $_[1], $_[2]);
840	}
841
842	=item line => [$eol, ]$cb->($handle, $line, $eol)	1413	=item line => [$eol, ]$cb->($handle, $line, $eol)
843		1414
844	The callback will be called only once a full line (including the end of	1415	The callback will be called only once a full line (including the end of
845	line marker, C<$eol>) has been read. This line (excluding the end of line	1416	line marker, C<$eol>) has been read. This line (excluding the end of line
846	marker) will be passed to the callback as second argument (C<$line>), and	1417	marker) will be passed to the callback as second argument (C<$line>), and
…		…
861	=cut	1432	=cut
862		1433
863	register_read_type line => sub {	1434	register_read_type line => sub {
864	my ($self, $cb, $eol) = @_;	1435	my ($self, $cb, $eol) = @_;
865		1436
866	$eol = qr|(\015?\012)| if @_ < 3;	1437	if (@_ < 3) {
		1438	# this is more than twice as fast as the generic code below
		1439	sub {
		1440	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		1441
		1442	$cb->($_[0], $1, $2);
		1443	1
		1444	}
		1445	} else {
867	$eol = quotemeta $eol unless ref $eol;	1446	$eol = quotemeta $eol unless ref $eol;
868	$eol = qr|^(.*?)($eol)|s;	1447	$eol = qr|^(.*?)($eol)|s;
869		1448
870	sub {	1449	sub {
871	$_[0]{rbuf} =~ s/$eol// or return;	1450	$_[0]{rbuf} =~ s/$eol// or return;
872		1451
873	$cb->($_[0], $1, $2);	1452	$cb->($_[0], $1, $2);
		1453	1
874	1	1454	}
875	}	1455	}
876	};	1456	};
877
878	# compatibility with older API
879	sub push_read_line {
880	my $self = shift;
881	$self->push_read (line => @_);
882	}
883
884	sub unshift_read_line {
885	my $self = shift;
886	$self->unshift_read (line => @_);
887	}
888		1457
889	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)	1458	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
890		1459
891	Makes a regex match against the regex object C<$accept> and returns	1460	Makes a regex match against the regex object C<$accept> and returns
892	everything up to and including the match.	1461	everything up to and including the match.
…		…
910	the receive buffer when neither C<$accept> nor C<$reject> match,	1479	the receive buffer when neither C<$accept> nor C<$reject> match,
911	and everything preceding and including the match will be accepted	1480	and everything preceding and including the match will be accepted
912	unconditionally. This is useful to skip large amounts of data that you	1481	unconditionally. This is useful to skip large amounts of data that you
913	know cannot be matched, so that the C<$accept> or C<$reject> regex do not	1482	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
914	have to start matching from the beginning. This is purely an optimisation	1483	have to start matching from the beginning. This is purely an optimisation
915	and is usually worth only when you expect more than a few kilobytes.	1484	and is usually worth it only when you expect more than a few kilobytes.
916		1485
917	Example: expect a http header, which ends at C<\015\012\015\012>. Since we	1486	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
918	expect the header to be very large (it isn't in practise, but...), we use	1487	expect the header to be very large (it isn't in practice, but...), we use
919	a skip regex to skip initial portions. The skip regex is tricky in that	1488	a skip regex to skip initial portions. The skip regex is tricky in that
920	it only accepts something not ending in either \015 or \012, as these are	1489	it only accepts something not ending in either \015 or \012, as these are
921	required for the accept regex.	1490	required for the accept regex.
922		1491
923	$handle->push_read (regex =>	1492	$handle->push_read (regex =>
…		…
942	return 1;	1511	return 1;
943	}	1512	}
944		1513
945	# reject	1514	# reject
946	if ($reject && $$rbuf =~ $reject) {	1515	if ($reject && $$rbuf =~ $reject) {
947	$self->_error (&Errno::EBADMSG);	1516	$self->_error (Errno::EBADMSG);
948	}	1517	}
949		1518
950	# skip	1519	# skip
951	if ($skip && $$rbuf =~ $skip) {	1520	if ($skip && $$rbuf =~ $skip) {
952	$data .= substr $$rbuf, 0, $+[0], "";	1521	$data .= substr $$rbuf, 0, $+[0], "";
…		…
968	my ($self, $cb) = @_;	1537	my ($self, $cb) = @_;
969		1538
970	sub {	1539	sub {
971	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {	1540	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
972	if ($_[0]{rbuf} =~ /[^0-9]/) {	1541	if ($_[0]{rbuf} =~ /[^0-9]/) {
973	$self->_error (&Errno::EBADMSG);	1542	$self->_error (Errno::EBADMSG);
974	}	1543	}
975	return;	1544	return;
976	}	1545	}
977		1546
978	my $len = $1;	1547	my $len = $1;
…		…
981	my $string = $_[1];	1550	my $string = $_[1];
982	$_[0]->unshift_read (chunk => 1, sub {	1551	$_[0]->unshift_read (chunk => 1, sub {
983	if ($_[1] eq ",") {	1552	if ($_[1] eq ",") {
984	$cb->($_[0], $string);	1553	$cb->($_[0], $string);
985	} else {	1554	} else {
986	$self->_error (&Errno::EBADMSG);	1555	$self->_error (Errno::EBADMSG);
987	}	1556	}
988	});	1557	});
989	});	1558	});
990		1559
991	1	1560	1
…		…
997	An octet string prefixed with an encoded length. The encoding C<$format>	1566	An octet string prefixed with an encoded length. The encoding C<$format>
998	uses the same format as a Perl C<pack> format, but must specify a single	1567	uses the same format as a Perl C<pack> format, but must specify a single
999	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an	1568	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1000	optional C<!>, C<< < >> or C<< > >> modifier).	1569	optional C<!>, C<< < >> or C<< > >> modifier).
1001		1570
1002	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.	1571	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1572	EPP uses a prefix of C<N> (4 octtes).
1003		1573
1004	Example: read a block of data prefixed by its length in BER-encoded	1574	Example: read a block of data prefixed by its length in BER-encoded
1005	format (very efficient).	1575	format (very efficient).
1006		1576
1007	$handle->push_read (packstring => "w", sub {	1577	$handle->push_read (packstring => "w", sub {
…		…
1013	register_read_type packstring => sub {	1583	register_read_type packstring => sub {
1014	my ($self, $cb, $format) = @_;	1584	my ($self, $cb, $format) = @_;
1015		1585
1016	sub {	1586	sub {
1017	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method	1587	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1018	defined (my $len = eval { unpack $format, $_[0]->{rbuf} })	1588	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1019	or return;	1589	or return;
1020		1590
		1591	$format = length pack $format, $len;
		1592
		1593	# bypass unshift if we already have the remaining chunk
		1594	if ($format + $len <= length $_[0]{rbuf}) {
		1595	my $data = substr $_[0]{rbuf}, $format, $len;
		1596	substr $_[0]{rbuf}, 0, $format + $len, "";
		1597	$cb->($_[0], $data);
		1598	} else {
1021	# remove prefix	1599	# remove prefix
1022	substr $_[0]->{rbuf}, 0, (length pack $format, $len), "";	1600	substr $_[0]{rbuf}, 0, $format, "";
1023		1601
1024	# read rest	1602	# read remaining chunk
1025	$_[0]->unshift_read (chunk => $len, $cb);	1603	$_[0]->unshift_read (chunk => $len, $cb);
		1604	}
1026		1605
1027	1	1606	1
1028	}	1607	}
1029	};	1608	};
1030		1609
1031	=item json => $cb->($handle, $hash_or_arrayref)	1610	=item json => $cb->($handle, $hash_or_arrayref)
1032		1611
1033	Reads a JSON object or array, decodes it and passes it to the callback.	1612	Reads a JSON object or array, decodes it and passes it to the
		1613	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1034		1614
1035	If a C<json> object was passed to the constructor, then that will be used	1615	If a C<json> object was passed to the constructor, then that will be used
1036	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1616	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1037		1617
1038	This read type uses the incremental parser available with JSON version	1618	This read type uses the incremental parser available with JSON version
…		…
1045	the C<json> write type description, above, for an actual example.	1625	the C<json> write type description, above, for an actual example.
1046		1626
1047	=cut	1627	=cut
1048		1628
1049	register_read_type json => sub {	1629	register_read_type json => sub {
1050	my ($self, $cb, $accept, $reject, $skip) = @_;	1630	my ($self, $cb) = @_;
1051		1631
1052	require JSON;	1632	my $json = $self->{json} ||= json_coder;
1053		1633
1054	my $data;	1634	my $data;
1055	my $rbuf = \$self->{rbuf};	1635	my $rbuf = \$self->{rbuf};
1056		1636
1057	my $json = $self->{json} ||= JSON->new->utf8;
1058
1059	sub {	1637	sub {
1060	my $ref = $json->incr_parse ($self->{rbuf});	1638	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1061		1639
1062	if ($ref) {	1640	if ($ref) {
1063	$self->{rbuf} = $json->incr_text;	1641	$self->{rbuf} = $json->incr_text;
1064	$json->incr_text = "";	1642	$json->incr_text = "";
1065	$cb->($self, $ref);	1643	$cb->($self, $ref);
1066		1644
1067	1	1645	1
		1646	} elsif ($@) {
		1647	# error case
		1648	$json->incr_skip;
		1649
		1650	$self->{rbuf} = $json->incr_text;
		1651	$json->incr_text = "";
		1652
		1653	$self->_error (Errno::EBADMSG);
		1654
		1655	()
1068	} else {	1656	} else {
1069	$self->{rbuf} = "";	1657	$self->{rbuf} = "";
		1658
1070	()	1659	()
1071	}	1660	}
1072	}	1661	}
1073	};	1662	};
1074		1663
		1664	=item storable => $cb->($handle, $ref)
		1665
		1666	Deserialises a L<Storable> frozen representation as written by the
		1667	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1668	data).
		1669
		1670	Raises C<EBADMSG> error if the data could not be decoded.
		1671
		1672	=cut
		1673
		1674	register_read_type storable => sub {
		1675	my ($self, $cb) = @_;
		1676
		1677	require Storable;
		1678
		1679	sub {
		1680	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1681	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1682	or return;
		1683
		1684	my $format = length pack "w", $len;
		1685
		1686	# bypass unshift if we already have the remaining chunk
		1687	if ($format + $len <= length $_[0]{rbuf}) {
		1688	my $data = substr $_[0]{rbuf}, $format, $len;
		1689	substr $_[0]{rbuf}, 0, $format + $len, "";
		1690	$cb->($_[0], Storable::thaw ($data));
		1691	} else {
		1692	# remove prefix
		1693	substr $_[0]{rbuf}, 0, $format, "";
		1694
		1695	# read remaining chunk
		1696	$_[0]->unshift_read (chunk => $len, sub {
		1697	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1698	$cb->($_[0], $ref);
		1699	} else {
		1700	$self->_error (Errno::EBADMSG);
		1701	}
		1702	});
		1703	}
		1704
		1705	1
		1706	}
		1707	};
		1708
1075	=back	1709	=back
1076		1710
1077	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)	1711	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1078		1712
1079	This function (not method) lets you add your own types to C<push_read>.	1713	Instead of one of the predefined types, you can also specify the name
		1714	of a package. AnyEvent will try to load the package and then expects to
		1715	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1716	progressively tries to load the parent package until it either finds the
		1717	function (good) or runs out of packages (bad).
1080		1718
1081	Whenever the given C<type> is used, C<push_read> will invoke the code	1719	Whenever this type is used, C<push_read> will invoke the function with the
1082	reference with the handle object, the callback and the remaining	1720	handle object, the original callback and the remaining arguments.
1083	arguments.
1084		1721
1085	The code reference is supposed to return a callback (usually a closure)	1722	The function is supposed to return a callback (usually a closure) that
1086	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1723	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1724	mentally treat the function as a "configurable read type to read callback"
		1725	converter.
1087		1726
1088	It should invoke the passed callback when it is done reading (remember to	1727	It should invoke the original callback when it is done reading (remember
1089	pass C<$handle> as first argument as all other callbacks do that).	1728	to pass C<$handle> as first argument as all other callbacks do that,
		1729	although there is no strict requirement on this).
1090		1730
1091	Note that this is a function, and all types registered this way will be
1092	global, so try to use unique names.
1093
1094	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1731	For examples, see the source of this module (F<perldoc -m
1095	search for C<register_read_type>)).	1732	AnyEvent::Handle>, search for C<register_read_type>)).
1096		1733
1097	=item $handle->stop_read	1734	=item $handle->stop_read
1098		1735
1099	=item $handle->start_read	1736	=item $handle->start_read
1100		1737
…		…
1106	Note that AnyEvent::Handle will automatically C<start_read> for you when	1743	Note that AnyEvent::Handle will automatically C<start_read> for you when
1107	you change the C<on_read> callback or push/unshift a read callback, and it	1744	you change the C<on_read> callback or push/unshift a read callback, and it
1108	will automatically C<stop_read> for you when neither C<on_read> is set nor	1745	will automatically C<stop_read> for you when neither C<on_read> is set nor
1109	there are any read requests in the queue.	1746	there are any read requests in the queue.
1110		1747
		1748	These methods will have no effect when in TLS mode (as TLS doesn't support
		1749	half-duplex connections).
		1750
1111	=cut	1751	=cut
1112		1752
1113	sub stop_read {	1753	sub stop_read {
1114	my ($self) = @_;	1754	my ($self) = @_;
1115		1755
1116	delete $self->{_rw};	1756	delete $self->{_rw} unless $self->{tls};
1117	}	1757	}
1118		1758
1119	sub start_read {	1759	sub start_read {
1120	my ($self) = @_;	1760	my ($self) = @_;
1121		1761
1122	unless ($self->{_rw} || $self->{_eof}) {	1762	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1123	Scalar::Util::weaken $self;	1763	Scalar::Util::weaken $self;
1124		1764
1125	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1765	$self->{_rw} = AE::io $self->{fh}, 0, sub {
1126	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1766	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1127	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1767	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1128		1768
1129	if ($len > 0) {	1769	if ($len > 0) {
1130	$self->{_activity} = AnyEvent->now;	1770	$self->{_activity} = $self->{_ractivity} = AE::now;
1131		1771
1132	$self->{filter_r}	1772	if ($self->{tls}) {
1133	? $self->{filter_r}($self, $rbuf)	1773	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1134	: $self->{_in_drain} || $self->_drain_rbuf;	1774
		1775	&_dotls ($self);
		1776	} else {
		1777	$self->_drain_rbuf;
		1778	}
		1779
		1780	if ($len == $self->{read_size}) {
		1781	$self->{read_size} *= 2;
		1782	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1783	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		1784	}
1135		1785
1136	} elsif (defined $len) {	1786	} elsif (defined $len) {
1137	delete $self->{_rw};	1787	delete $self->{_rw};
1138	$self->{_eof} = 1;	1788	$self->{_eof} = 1;
1139	$self->_drain_rbuf unless $self->{_in_drain};	1789	$self->_drain_rbuf;
1140		1790
1141	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	1791	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1142	return $self->_error ($!, 1);	1792	return $self->_error ($!, 1);
1143	}	1793	}
1144	});	1794	};
1145	}	1795	}
1146	}	1796	}
1147		1797
		1798	our $ERROR_SYSCALL;
		1799	our $ERROR_WANT_READ;
		1800
		1801	sub _tls_error {
		1802	my ($self, $err) = @_;
		1803
		1804	return $self->_error ($!, 1)
		1805	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1806
		1807	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1808
		1809	# reduce error string to look less scary
		1810	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1811
		1812	if ($self->{_on_starttls}) {
		1813	(delete $self->{_on_starttls})->($self, undef, $err);
		1814	&_freetls;
		1815	} else {
		1816	&_freetls;
		1817	$self->_error (Errno::EPROTO, 1, $err);
		1818	}
		1819	}
		1820
		1821	# poll the write BIO and send the data if applicable
		1822	# also decode read data if possible
		1823	# this is basiclaly our TLS state machine
		1824	# more efficient implementations are possible with openssl,
		1825	# but not with the buggy and incomplete Net::SSLeay.
1148	sub _dotls {	1826	sub _dotls {
1149	my ($self) = @_;	1827	my ($self) = @_;
1150		1828
1151	my $buf;	1829	my $tmp;
1152		1830
1153	if (length $self->{_tls_wbuf}) {	1831	if (length $self->{_tls_wbuf}) {
1154	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1832	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1155	substr $self->{_tls_wbuf}, 0, $len, "";	1833	substr $self->{_tls_wbuf}, 0, $tmp, "";
1156	}	1834	}
1157	}
1158		1835
		1836	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1837	return $self->_tls_error ($tmp)
		1838	if $tmp != $ERROR_WANT_READ
		1839	&& ($tmp != $ERROR_SYSCALL || $!);
		1840	}
		1841
		1842	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1843	unless (length $tmp) {
		1844	$self->{_on_starttls}
		1845	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1846	&_freetls;
		1847
		1848	if ($self->{on_stoptls}) {
		1849	$self->{on_stoptls}($self);
		1850	return;
		1851	} else {
		1852	# let's treat SSL-eof as we treat normal EOF
		1853	delete $self->{_rw};
		1854	$self->{_eof} = 1;
		1855	}
		1856	}
		1857
		1858	$self->{_tls_rbuf} .= $tmp;
		1859	$self->_drain_rbuf;
		1860	$self->{tls} or return; # tls session might have gone away in callback
		1861	}
		1862
		1863	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1864	return $self->_tls_error ($tmp)
		1865	if $tmp != $ERROR_WANT_READ
		1866	&& ($tmp != $ERROR_SYSCALL || $!);
		1867
1159	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1868	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1160	$self->{wbuf} .= $buf;	1869	$self->{wbuf} .= $tmp;
1161	$self->_drain_wbuf;	1870	$self->_drain_wbuf;
		1871	$self->{tls} or return; # tls session might have gone away in callback
1162	}	1872	}
1163		1873
1164	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1874	$self->{_on_starttls}
1165	if (length $buf) {	1875	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1166	$self->{rbuf} .= $buf;	1876	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1167	$self->_drain_rbuf unless $self->{_in_drain};
1168	} else {
1169	# let's treat SSL-eof as we treat normal EOF
1170	$self->{_eof} = 1;
1171	$self->_shutdown;
1172	return;
1173	}
1174	}
1175
1176	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1177
1178	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1179	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1180	return $self->_error ($!, 1);
1181	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1182	return $self->_error (&Errno::EIO, 1);
1183	}
1184
1185	# all others are fine for our purposes
1186	}
1187	}	1877	}
1188		1878
1189	=item $handle->starttls ($tls[, $tls_ctx])	1879	=item $handle->starttls ($tls[, $tls_ctx])
1190		1880
1191	Instead of starting TLS negotiation immediately when the AnyEvent::Handle	1881	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1192	object is created, you can also do that at a later time by calling	1882	object is created, you can also do that at a later time by calling
1193	C<starttls>.	1883	C<starttls>.
1194		1884
		1885	Starting TLS is currently an asynchronous operation - when you push some
		1886	write data and then call C<< ->starttls >> then TLS negotiation will start
		1887	immediately, after which the queued write data is then sent.
		1888
1195	The first argument is the same as the C<tls> constructor argument (either	1889	The first argument is the same as the C<tls> constructor argument (either
1196	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1890	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1197		1891
1198	The second argument is the optional C<Net::SSLeay::CTX> object that is	1892	The second argument is the optional C<AnyEvent::TLS> object that is used
1199	used when AnyEvent::Handle has to create its own TLS connection object.	1893	when AnyEvent::Handle has to create its own TLS connection object, or
		1894	a hash reference with C<< key => value >> pairs that will be used to
		1895	construct a new context.
1200		1896
1201	The TLS connection object will end up in C<< $handle->{tls} >> after this	1897	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1202	call and can be used or changed to your liking. Note that the handshake	1898	context in C<< $handle->{tls_ctx} >> after this call and can be used or
1203	might have already started when this function returns.	1899	changed to your liking. Note that the handshake might have already started
		1900	when this function returns.
1204		1901
		1902	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1903	handshakes on the same stream. It is best to not attempt to use the
		1904	stream after stopping TLS.
		1905
		1906	This method may invoke callbacks (and therefore the handle might be
		1907	destroyed after it returns).
		1908
1205	=cut	1909	=cut
		1910
		1911	our %TLS_CACHE; #TODO not yet documented, should we?
1206		1912
1207	sub starttls {	1913	sub starttls {
1208	my ($self, $ssl, $ctx) = @_;	1914	my ($self, $tls, $ctx) = @_;
1209		1915
1210	$self->stoptls;	1916	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1917	if $self->{tls};
1211		1918
1212	if ($ssl eq "accept") {	1919	$self->{tls} = $tls;
1213	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1920	$self->{tls_ctx} = $ctx if @_ > 2;
1214	Net::SSLeay::set_accept_state ($ssl);	1921
1215	} elsif ($ssl eq "connect") {	1922	return unless $self->{fh};
1216	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1923
1217	Net::SSLeay::set_connect_state ($ssl);	1924	require Net::SSLeay;
		1925
		1926	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		1927	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1928
		1929	$tls = delete $self->{tls};
		1930	$ctx = $self->{tls_ctx};
		1931
		1932	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1933
		1934	if ("HASH" eq ref $ctx) {
		1935	require AnyEvent::TLS;
		1936
		1937	if ($ctx->{cache}) {
		1938	my $key = $ctx+0;
		1939	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1940	} else {
		1941	$ctx = new AnyEvent::TLS %$ctx;
		1942	}
		1943	}
1218	}	1944
1219		1945	$self->{tls_ctx} = $ctx || TLS_CTX ();
1220	$self->{tls} = $ssl;	1946	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1221		1947
1222	# basically, this is deep magic (because SSL_read should have the same issues)	1948	# basically, this is deep magic (because SSL_read should have the same issues)
1223	# but the openssl maintainers basically said: "trust us, it just works".	1949	# but the openssl maintainers basically said: "trust us, it just works".
1224	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1950	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1225	# and mismaintained ssleay-module doesn't even offer them).	1951	# and mismaintained ssleay-module doesn't even offer them).
1226	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1952	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1953	#
		1954	# in short: this is a mess.
		1955	#
		1956	# note that we do not try to keep the length constant between writes as we are required to do.
		1957	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1958	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1959	# have identity issues in that area.
1227	Net::SSLeay::CTX_set_mode ($self->{tls},	1960	# Net::SSLeay::CTX_set_mode ($ssl,
1228	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1961	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1229	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1962	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1963	Net::SSLeay::CTX_set_mode ($tls, 1|2);
1230		1964
1231	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1965	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1232	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1966	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1233		1967
		1968	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		1969
1234	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1970	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1235		1971
1236	$self->{filter_w} = sub {	1972	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1237	$_[0]{_tls_wbuf} .= ${$_[1]};	1973	if $self->{on_starttls};
1238	&_dotls;	1974
1239	};	1975	&_dotls; # need to trigger the initial handshake
1240	$self->{filter_r} = sub {	1976	$self->start_read; # make sure we actually do read
1241	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1242	&_dotls;
1243	};
1244	}	1977	}
1245		1978
1246	=item $handle->stoptls	1979	=item $handle->stoptls
1247		1980
1248	Destroys the SSL connection, if any. Partial read or write data will be	1981	Shuts down the SSL connection - this makes a proper EOF handshake by
1249	lost.	1982	sending a close notify to the other side, but since OpenSSL doesn't
		1983	support non-blocking shut downs, it is not guaranteed that you can re-use
		1984	the stream afterwards.
		1985
		1986	This method may invoke callbacks (and therefore the handle might be
		1987	destroyed after it returns).
1250		1988
1251	=cut	1989	=cut
1252		1990
1253	sub stoptls {	1991	sub stoptls {
1254	my ($self) = @_;	1992	my ($self) = @_;
1255		1993
1256	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1994	if ($self->{tls} && $self->{fh}) {
		1995	Net::SSLeay::shutdown ($self->{tls});
1257		1996
1258	delete $self->{_rbio};	1997	&_dotls;
1259	delete $self->{_wbio};	1998
1260	delete $self->{_tls_wbuf};	1999	# # we don't give a shit. no, we do, but we can't. no...#d#
1261	delete $self->{filter_r};	2000	# # we, we... have to use openssl :/#d#
1262	delete $self->{filter_w};	2001	# &_freetls;#d#
		2002	}
		2003	}
		2004
		2005	sub _freetls {
		2006	my ($self) = @_;
		2007
		2008	return unless $self->{tls};
		2009
		2010	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2011	if $self->{tls} > 0;
		2012
		2013	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1263	}	2014	}
1264		2015
1265	sub DESTROY {	2016	sub DESTROY {
1266	my $self = shift;	2017	my ($self) = @_;
1267		2018
1268	$self->stoptls;	2019	&_freetls;
1269		2020
1270	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	2021	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1271		2022
1272	if ($linger && length $self->{wbuf}) {	2023	if ($linger && length $self->{wbuf} && $self->{fh}) {
1273	my $fh = delete $self->{fh};	2024	my $fh = delete $self->{fh};
1274	my $wbuf = delete $self->{wbuf};	2025	my $wbuf = delete $self->{wbuf};
1275		2026
1276	my @linger;	2027	my @linger;
1277		2028
1278	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {	2029	push @linger, AE::io $fh, 1, sub {
1279	my $len = syswrite $fh, $wbuf, length $wbuf;	2030	my $len = syswrite $fh, $wbuf, length $wbuf;
1280		2031
1281	if ($len > 0) {	2032	if ($len > 0) {
1282	substr $wbuf, 0, $len, "";	2033	substr $wbuf, 0, $len, "";
1283	} else {	2034	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1284	@linger = (); # end	2035	@linger = (); # end
1285	}	2036	}
		2037	};
		2038	push @linger, AE::timer $linger, 0, sub {
		2039	@linger = ();
		2040	};
		2041	}
		2042	}
		2043
		2044	=item $handle->destroy
		2045
		2046	Shuts down the handle object as much as possible - this call ensures that
		2047	no further callbacks will be invoked and as many resources as possible
		2048	will be freed. Any method you will call on the handle object after
		2049	destroying it in this way will be silently ignored (and it will return the
		2050	empty list).
		2051
		2052	Normally, you can just "forget" any references to an AnyEvent::Handle
		2053	object and it will simply shut down. This works in fatal error and EOF
		2054	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2055	callback, so when you want to destroy the AnyEvent::Handle object from
		2056	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2057	that case.
		2058
		2059	Destroying the handle object in this way has the advantage that callbacks
		2060	will be removed as well, so if those are the only reference holders (as
		2061	is common), then one doesn't need to do anything special to break any
		2062	reference cycles.
		2063
		2064	The handle might still linger in the background and write out remaining
		2065	data, as specified by the C<linger> option, however.
		2066
		2067	=cut
		2068
		2069	sub destroy {
		2070	my ($self) = @_;
		2071
		2072	$self->DESTROY;
		2073	%$self = ();
		2074	bless $self, "AnyEvent::Handle::destroyed";
		2075	}
		2076
		2077	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2078	#nop
		2079	}
		2080
		2081	=item $handle->destroyed
		2082
		2083	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2084	->destroy >>, true otherwise.
		2085
		2086	Can be useful to decide whether the handle is still valid after some
		2087	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2088	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2089	can destroy the handle, so work can be avoided by checking sometimes:
		2090
		2091	$hdl->starttls ("accept");
		2092	return if $hdl->destroyed;
		2093	$hdl->push_write (...
		2094
		2095	Note that the call to C<push_write> will silently be ignored if the handle
		2096	has been destroyed, so often you can just ignore the possibility of the
		2097	handle being destroyed.
		2098
		2099	=cut
		2100
		2101	sub destroyed { 0 }
		2102	sub AnyEvent::Handle::destroyed::destroyed { 1 }
		2103
		2104	=item AnyEvent::Handle::TLS_CTX
		2105
		2106	This function creates and returns the AnyEvent::TLS object used by default
		2107	for TLS mode.
		2108
		2109	The context is created by calling L<AnyEvent::TLS> without any arguments.
		2110
		2111	=cut
		2112
		2113	our $TLS_CTX;
		2114
		2115	sub TLS_CTX() {
		2116	$TLS_CTX ||= do {
		2117	require AnyEvent::TLS;
		2118
		2119	new AnyEvent::TLS
		2120	}
		2121	}
		2122
		2123	=back
		2124
		2125
		2126	=head1 NONFREQUENTLY ASKED QUESTIONS
		2127
		2128	=over 4
		2129
		2130	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2131	still get further invocations!
		2132
		2133	That's because AnyEvent::Handle keeps a reference to itself when handling
		2134	read or write callbacks.
		2135
		2136	It is only safe to "forget" the reference inside EOF or error callbacks,
		2137	from within all other callbacks, you need to explicitly call the C<<
		2138	->destroy >> method.
		2139
		2140	=item Why is my C<on_eof> callback never called?
		2141
		2142	Probably because your C<on_error> callback is being called instead: When
		2143	you have outstanding requests in your read queue, then an EOF is
		2144	considered an error as you clearly expected some data.
		2145
		2146	To avoid this, make sure you have an empty read queue whenever your handle
		2147	is supposed to be "idle" (i.e. connection closes are O.K.). You cna set
		2148	an C<on_read> handler that simply pushes the first read requests in the
		2149	queue.
		2150
		2151	See also the next question, which explains this in a bit more detail.
		2152
		2153	=item How can I serve requests in a loop?
		2154
		2155	Most protocols consist of some setup phase (authentication for example)
		2156	followed by a request handling phase, where the server waits for requests
		2157	and handles them, in a loop.
		2158
		2159	There are two important variants: The first (traditional, better) variant
		2160	handles requests until the server gets some QUIT command, causing it to
		2161	close the connection first (highly desirable for a busy TCP server). A
		2162	client dropping the connection is an error, which means this variant can
		2163	detect an unexpected detection close.
		2164
		2165	To handle this case, always make sure you have a on-empty read queue, by
		2166	pushing the "read request start" handler on it:
		2167
		2168	# we assume a request starts with a single line
		2169	my @start_request; @start_request = (line => sub {
		2170	my ($hdl, $line) = @_;
		2171
		2172	... handle request
		2173
		2174	# push next request read, possibly from a nested callback
		2175	$hdl->push_read (@start_request);
		2176	});
		2177
		2178	# auth done, now go into request handling loop
		2179	# now push the first @start_request
		2180	$hdl->push_read (@start_request);
		2181
		2182	By always having an outstanding C<push_read>, the handle always expects
		2183	some data and raises the C<EPIPE> error when the connction is dropped
		2184	unexpectedly.
		2185
		2186	The second variant is a protocol where the client can drop the connection
		2187	at any time. For TCP, this means that the server machine may run out of
		2188	sockets easier, and in general, it means you cnanot distinguish a protocl
		2189	failure/client crash from a normal connection close. Nevertheless, these
		2190	kinds of protocols are common (and sometimes even the best solution to the
		2191	problem).
		2192
		2193	Having an outstanding read request at all times is possible if you ignore
		2194	C<EPIPE> errors, but this doesn't help with when the client drops the
		2195	connection during a request, which would still be an error.
		2196
		2197	A better solution is to push the initial request read in an C<on_read>
		2198	callback. This avoids an error, as when the server doesn't expect data
		2199	(i.e. is idly waiting for the next request, an EOF will not raise an
		2200	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2201	and simpler:
		2202
		2203	# auth done, now go into request handling loop
		2204	$hdl->on_read (sub {
		2205	my ($hdl) = @_;
		2206
		2207	# called each time we receive data but the read queue is empty
		2208	# simply start read the request
		2209
		2210	$hdl->push_read (line => sub {
		2211	my ($hdl, $line) = @_;
		2212
		2213	... handle request
		2214
		2215	# do nothing special when the request has been handled, just
		2216	# let the request queue go empty.
1286	});	2217	});
1287	push @linger, AnyEvent->timer (after => $linger, cb => sub {
1288	@linger = ();
1289	});	2218	});
		2219
		2220	=item I get different callback invocations in TLS mode/Why can't I pause
		2221	reading?
		2222
		2223	Unlike, say, TCP, TLS connections do not consist of two independent
		2224	communication channels, one for each direction. Or put differently, the
		2225	read and write directions are not independent of each other: you cannot
		2226	write data unless you are also prepared to read, and vice versa.
		2227
		2228	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2229	callback invocations when you are not expecting any read data - the reason
		2230	is that AnyEvent::Handle always reads in TLS mode.
		2231
		2232	During the connection, you have to make sure that you always have a
		2233	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2234	connection (or when you no longer want to use it) you can call the
		2235	C<destroy> method.
		2236
		2237	=item How do I read data until the other side closes the connection?
		2238
		2239	If you just want to read your data into a perl scalar, the easiest way
		2240	to achieve this is by setting an C<on_read> callback that does nothing,
		2241	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2242	will be in C<$_[0]{rbuf}>:
		2243
		2244	$handle->on_read (sub { });
		2245	$handle->on_eof (undef);
		2246	$handle->on_error (sub {
		2247	my $data = delete $_[0]{rbuf};
		2248	});
		2249
		2250	The reason to use C<on_error> is that TCP connections, due to latencies
		2251	and packets loss, might get closed quite violently with an error, when in
		2252	fact all data has been received.
		2253
		2254	It is usually better to use acknowledgements when transferring data,
		2255	to make sure the other side hasn't just died and you got the data
		2256	intact. This is also one reason why so many internet protocols have an
		2257	explicit QUIT command.
		2258
		2259	=item I don't want to destroy the handle too early - how do I wait until
		2260	all data has been written?
		2261
		2262	After writing your last bits of data, set the C<on_drain> callback
		2263	and destroy the handle in there - with the default setting of
		2264	C<low_water_mark> this will be called precisely when all data has been
		2265	written to the socket:
		2266
		2267	$handle->push_write (...);
		2268	$handle->on_drain (sub {
		2269	warn "all data submitted to the kernel\n";
		2270	undef $handle;
		2271	});
		2272
		2273	If you just want to queue some data and then signal EOF to the other side,
		2274	consider using C<< ->push_shutdown >> instead.
		2275
		2276	=item I want to contact a TLS/SSL server, I don't care about security.
		2277
		2278	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2279	connect to it and then create the AnyEvent::Handle with the C<tls>
		2280	parameter:
		2281
		2282	tcp_connect $host, $port, sub {
		2283	my ($fh) = @_;
		2284
		2285	my $handle = new AnyEvent::Handle
		2286	fh => $fh,
		2287	tls => "connect",
		2288	on_error => sub { ... };
		2289
		2290	$handle->push_write (...);
1290	}	2291	};
1291	}
1292		2292
1293	=item AnyEvent::Handle::TLS_CTX	2293	=item I want to contact a TLS/SSL server, I do care about security.
1294		2294
1295	This function creates and returns the Net::SSLeay::CTX object used by	2295	Then you should additionally enable certificate verification, including
1296	default for TLS mode.	2296	peername verification, if the protocol you use supports it (see
		2297	L<AnyEvent::TLS>, C<verify_peername>).
1297		2298
1298	The context is created like this:	2299	E.g. for HTTPS:
1299		2300
1300	Net::SSLeay::load_error_strings;	2301	tcp_connect $host, $port, sub {
1301	Net::SSLeay::SSLeay_add_ssl_algorithms;	2302	my ($fh) = @_;
1302	Net::SSLeay::randomize;
1303		2303
1304	my $CTX = Net::SSLeay::CTX_new;	2304	my $handle = new AnyEvent::Handle
		2305	fh => $fh,
		2306	peername => $host,
		2307	tls => "connect",
		2308	tls_ctx => { verify => 1, verify_peername => "https" },
		2309	...
1305		2310
1306	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL	2311	Note that you must specify the hostname you connected to (or whatever
		2312	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2313	peername verification will be done.
1307		2314
1308	=cut	2315	The above will use the system-dependent default set of trusted CA
		2316	certificates. If you want to check against a specific CA, add the
		2317	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
1309		2318
1310	our $TLS_CTX;	2319	tls_ctx => {
		2320	verify => 1,
		2321	verify_peername => "https",
		2322	ca_file => "my-ca-cert.pem",
		2323	},
1311		2324
1312	sub TLS_CTX() {	2325	=item I want to create a TLS/SSL server, how do I do that?
1313	$TLS_CTX || do {
1314	require Net::SSLeay;
1315		2326
1316	Net::SSLeay::load_error_strings ();	2327	Well, you first need to get a server certificate and key. You have
1317	Net::SSLeay::SSLeay_add_ssl_algorithms ();	2328	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
1318	Net::SSLeay::randomize ();	2329	self-signed certificate (cheap. check the search engine of your choice,
		2330	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2331	nice program for that purpose).
1319		2332
1320	$TLS_CTX = Net::SSLeay::CTX_new ();	2333	Then create a file with your private key (in PEM format, see
		2334	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2335	file should then look like this:
1321		2336
1322	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());	2337	-----BEGIN RSA PRIVATE KEY-----
		2338	...header data
		2339	... lots of base64'y-stuff
		2340	-----END RSA PRIVATE KEY-----
1323		2341
1324	$TLS_CTX	2342	-----BEGIN CERTIFICATE-----
1325	}	2343	... lots of base64'y-stuff
1326	}	2344	-----END CERTIFICATE-----
		2345
		2346	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2347	specify this file as C<cert_file>:
		2348
		2349	tcp_server undef, $port, sub {
		2350	my ($fh) = @_;
		2351
		2352	my $handle = new AnyEvent::Handle
		2353	fh => $fh,
		2354	tls => "accept",
		2355	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2356	...
		2357
		2358	When you have intermediate CA certificates that your clients might not
		2359	know about, just append them to the C<cert_file>.
1327		2360
1328	=back	2361	=back
		2362
1329		2363
1330	=head1 SUBCLASSING AnyEvent::Handle	2364	=head1 SUBCLASSING AnyEvent::Handle
1331		2365
1332	In many cases, you might want to subclass AnyEvent::Handle.	2366	In many cases, you might want to subclass AnyEvent::Handle.
1333		2367
…		…
1337	=over 4	2371	=over 4
1338		2372
1339	=item * all constructor arguments become object members.	2373	=item * all constructor arguments become object members.
1340		2374
1341	At least initially, when you pass a C<tls>-argument to the constructor it	2375	At least initially, when you pass a C<tls>-argument to the constructor it
1342	will end up in C<< $handle->{tls} >>. Those members might be changes or	2376	will end up in C<< $handle->{tls} >>. Those members might be changed or
1343	mutated later on (for example C<tls> will hold the TLS connection object).	2377	mutated later on (for example C<tls> will hold the TLS connection object).
1344		2378
1345	=item * other object member names are prefixed with an C<_>.	2379	=item * other object member names are prefixed with an C<_>.
1346		2380
1347	All object members not explicitly documented (internal use) are prefixed	2381	All object members not explicitly documented (internal use) are prefixed
…		…
1350		2384
1351	=item * all members not documented here and not prefixed with an underscore	2385	=item * all members not documented here and not prefixed with an underscore
1352	are free to use in subclasses.	2386	are free to use in subclasses.
1353		2387
1354	Of course, new versions of AnyEvent::Handle may introduce more "public"	2388	Of course, new versions of AnyEvent::Handle may introduce more "public"
1355	member variables, but thats just life, at least it is documented.	2389	member variables, but that's just life. At least it is documented.
1356		2390
1357	=back	2391	=back
1358		2392
1359	=head1 AUTHOR	2393	=head1 AUTHOR
1360		2394

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