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Revision 1.14 by root, Sat May 17 19:05:51 2008 UTC vs.
Revision 1.177 by root, Sun Aug 9 00:24:35 2009 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict;
5
6	use AnyEvent ();
7	use AnyEvent::Util ();
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 filehandles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16
17	=cut
18
19	our $VERSION = '0.02';
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 $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	12	my $hdl; $hdl = new AnyEvent::Handle
29
30	#TODO
31
32	# or use the constructor to pass the callback:
33
34	my $ae_fh2 =
35	AnyEvent::Handle->new (
36	fh => \*STDIN,	13	fh => \*STDIN,
37	on_eof => sub {	14	on_error => sub {
38	$cv->broadcast;	15	my ($hdl, $fatal, $msg) = @_;
39	},	16	warn "got error $msg\n";
40	#TODO	17	$hdl->destroy;
		18	$cv->send;
41	);	19	);
42		20
43	$cv->wait;	21	# send some request line
		22	$hdl->push_write ("getinfo\015\012");
		23
		24	# read the response line
		25	$hdl->push_read (line => sub {
		26	my ($hdl, $line) = @_;
		27	warn "got line <$line>\n";
		28	$cv->send;
		29	});
		30
		31	$cv->recv;
44		32
45	=head1 DESCRIPTION	33	=head1 DESCRIPTION
46		34
47	This module is a helper module to make it easier to do event-based I/O on	35	This module is a helper module to make it easier to do event-based I/O on
48	filehandles. For utility functions for doing non-blocking connects and accepts	36	filehandles.
49	on sockets see L<AnyEvent::Util>.	37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
50		40
51	In the following, when the documentation refers to of "bytes" then this	41	In the following, when the documentation refers to of "bytes" then this
52	means characters. As sysread and syswrite are used for all I/O, their	42	means characters. As sysread and syswrite are used for all I/O, their
53	treatment of characters applies to this module as well.	43	treatment of characters applies to this module as well.
54		44
		45	At the very minimum, you should specify C<fh> or C<connect>, and the
		46	C<on_error> callback.
		47
55	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
56	argument.	49	argument.
57		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
58	=head1 METHODS	65	=head1 METHODS
59		66
60	=over 4	67	=over 4
61		68
62	=item B<new (%args)>	69	=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
63		70
64	The constructor supports these arguments (all as key => value pairs).	71	The constructor supports these arguments (all as C<< key => value >> pairs).
65		72
66	=over 4	73	=over 4
67		74
68	=item fh => $filehandle [MANDATORY]	75	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
69		76
70	The filehandle this L<AnyEvent::Handle> object will operate on.	77	The filehandle this L<AnyEvent::Handle> object will operate on.
71
72	NOTE: The filehandle will be set to non-blocking (using	78	NOTE: The filehandle will be set to non-blocking mode (using
73	AnyEvent::Util::fh_nonblocking).	79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
74		81
75	=item on_eof => $cb->($self) [MANDATORY]	82	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
76		83
77	Set the callback to be called on EOF.	84	Try to connect to the specified host and service (port), using
		85	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		86	default C<peername>.
78		87
		88	You have to specify either this parameter, or C<fh>, above.
		89
		90	It is possible to push requests on the read and write queues, and modify
		91	properties of the stream, even while AnyEvent::Handle is connecting.
		92
		93	When this parameter is specified, then the C<on_prepare>,
		94	C<on_connect_error> and C<on_connect> callbacks will be called under the
		95	appropriate circumstances:
		96
		97	=over 4
		98
79	=item on_error => $cb->($self)	99	=item on_prepare => $cb->($handle)
80		100
		101	This (rarely used) callback is called before a new connection is
		102	attempted, but after the file handle has been created. It could be used to
		103	prepare the file handle with parameters required for the actual connect
		104	(as opposed to settings that can be changed when the connection is already
		105	established).
		106
		107	The return value of this callback should be the connect timeout value in
		108	seconds (or C<0>, or C<undef>, or the empty list, to indicate the default
		109	timeout is to be used).
		110
		111	=item on_connect => $cb->($handle, $host, $port, $retry->())
		112
		113	This callback is called when a connection has been successfully established.
		114
		115	The actual numeric host and port (the socket peername) are passed as
		116	parameters, together with a retry callback.
		117
		118	When, for some reason, the handle is not acceptable, then calling
		119	C<$retry> will continue with the next conenction target (in case of
		120	multi-homed hosts or SRV records there can be multiple connection
		121	endpoints). When it is called then the read and write queues, eof status,
		122	tls status and similar properties of the handle are being reset.
		123
		124	In most cases, ignoring the C<$retry> parameter is the way to go.
		125
		126	=item on_connect_error => $cb->($handle, $message)
		127
		128	This callback is called when the conenction could not be
		129	established. C<$!> will contain the relevant error code, and C<$message> a
		130	message describing it (usually the same as C<"$!">).
		131
		132	If this callback isn't specified, then C<on_error> will be called with a
		133	fatal error instead.
		134
		135	=back
		136
		137	=item on_error => $cb->($handle, $fatal, $message)
		138
81	This is the fatal error callback, that is called when, well, a fatal error	139	This is the error callback, which is called when, well, some error
82	ocurs, such as not being able to resolve the hostname, failure to connect	140	occured, such as not being able to resolve the hostname, failure to
83	or a read error.	141	connect or a read error.
84		142
85	The object will not be in a usable state when this callback has been	143	Some errors are fatal (which is indicated by C<$fatal> being true). On
86	called.	144	fatal errors the handle object will be destroyed (by a call to C<< ->
		145	destroy >>) after invoking the error callback (which means you are free to
		146	examine the handle object). Examples of fatal errors are an EOF condition
		147	with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In
		148	cases where the other side can close the connection at their will it is
		149	often easiest to not report C<EPIPE> errors in this callback.
		150
		151	AnyEvent::Handle tries to find an appropriate error code for you to check
		152	against, but in some cases (TLS errors), this does not work well. It is
		153	recommended to always output the C<$message> argument in human-readable
		154	error messages (it's usually the same as C<"$!">).
		155
		156	Non-fatal errors can be retried by simply returning, but it is recommended
		157	to simply ignore this parameter and instead abondon the handle object
		158	when this callback is invoked. Examples of non-fatal errors are timeouts
		159	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
87		160
88	On callback entrance, the value of C<$!> contains the operating system	161	On callback entrance, the value of C<$!> contains the operating system
89	error (or C<ENOSPC> or C<EPIPE>).	162	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		163	C<EPROTO>).
90		164
91	While not mandatory, it is I<highly> recommended to set this callback, as	165	While not mandatory, it is I<highly> recommended to set this callback, as
92	you will not be notified of errors otherwise. The default simply calls	166	you will not be notified of errors otherwise. The default simply calls
93	die.	167	C<croak>.
94		168
95	=item on_read => $cb->($self)	169	=item on_read => $cb->($handle)
96		170
97	This sets the default read callback, which is called when data arrives	171	This sets the default read callback, which is called when data arrives
98	and no read request is in the queue.	172	and no read request is in the queue (unlike read queue callbacks, this
		173	callback will only be called when at least one octet of data is in the
		174	read buffer).
99		175
100	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	176	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
101	method or acces sthe C<$self->{rbuf}> member directly.	177	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		178	must not enlarge or modify the read buffer, you can only remove data at
		179	the beginning from it.
102		180
103	When an EOF condition is detected then AnyEvent::Handle will first try to	181	When an EOF condition is detected then AnyEvent::Handle will first try to
104	feed all the remaining data to the queued callbacks and C<on_read> before	182	feed all the remaining data to the queued callbacks and C<on_read> before
105	calling the C<on_eof> callback. If no progress can be made, then a fatal	183	calling the C<on_eof> callback. If no progress can be made, then a fatal
106	error will be raised (with C<$!> set to C<EPIPE>).	184	error will be raised (with C<$!> set to C<EPIPE>).
107		185
		186	Note that, unlike requests in the read queue, an C<on_read> callback
		187	doesn't mean you I<require> some data: if there is an EOF and there
		188	are outstanding read requests then an error will be flagged. With an
		189	C<on_read> callback, the C<on_eof> callback will be invoked.
		190
		191	=item on_eof => $cb->($handle)
		192
		193	Set the callback to be called when an end-of-file condition is detected,
		194	i.e. in the case of a socket, when the other side has closed the
		195	connection cleanly, and there are no outstanding read requests in the
		196	queue (if there are read requests, then an EOF counts as an unexpected
		197	connection close and will be flagged as an error).
		198
		199	For sockets, this just means that the other side has stopped sending data,
		200	you can still try to write data, and, in fact, one can return from the EOF
		201	callback and continue writing data, as only the read part has been shut
		202	down.
		203
		204	If an EOF condition has been detected but no C<on_eof> callback has been
		205	set, then a fatal error will be raised with C<$!> set to <0>.
		206
108	=item on_drain => $cb->()	207	=item on_drain => $cb->($handle)
109		208
110	This sets the callback that is called when the write buffer becomes empty	209	This sets the callback that is called when the write buffer becomes empty
111	(or when the callback is set and the buffer is empty already).	210	(or when the callback is set and the buffer is empty already).
112		211
113	To append to the write buffer, use the C<< ->push_write >> method.	212	To append to the write buffer, use the C<< ->push_write >> method.
114		213
		214	This callback is useful when you don't want to put all of your write data
		215	into the queue at once, for example, when you want to write the contents
		216	of some file to the socket you might not want to read the whole file into
		217	memory and push it into the queue, but instead only read more data from
		218	the file when the write queue becomes empty.
		219
		220	=item timeout => $fractional_seconds
		221
		222	=item rtimeout => $fractional_seconds
		223
		224	=item wtimeout => $fractional_seconds
		225
		226	If non-zero, then these enables an "inactivity" timeout: whenever this
		227	many seconds pass without a successful read or write on the underlying
		228	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
		229	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		230	error will be raised).
		231
		232	There are three variants of the timeouts that work fully independent
		233	of each other, for both read and write, just read, and just write:
		234	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		235	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		236	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		237
		238	Note that timeout processing is also active when you currently do not have
		239	any outstanding read or write requests: If you plan to keep the connection
		240	idle then you should disable the timout temporarily or ignore the timeout
		241	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		242	restart the timeout.
		243
		244	Zero (the default) disables this timeout.
		245
		246	=item on_timeout => $cb->($handle)
		247
		248	Called whenever the inactivity timeout passes. If you return from this
		249	callback, then the timeout will be reset as if some activity had happened,
		250	so this condition is not fatal in any way.
		251
115	=item rbuf_max => <bytes>	252	=item rbuf_max => <bytes>
116		253
117	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	254	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
118	when the read buffer ever (strictly) exceeds this size. This is useful to	255	when the read buffer ever (strictly) exceeds this size. This is useful to
119	avoid denial-of-service attacks.	256	avoid some forms of denial-of-service attacks.
120		257
121	For example, a server accepting connections from untrusted sources should	258	For example, a server accepting connections from untrusted sources should
122	be configured to accept only so-and-so much data that it cannot act on	259	be configured to accept only so-and-so much data that it cannot act on
123	(for example, when expecting a line, an attacker could send an unlimited	260	(for example, when expecting a line, an attacker could send an unlimited
124	amount of data without a callback ever being called as long as the line	261	amount of data without a callback ever being called as long as the line
125	isn't finished).	262	isn't finished).
126		263
		264	=item autocork => <boolean>
		265
		266	When disabled (the default), then C<push_write> will try to immediately
		267	write the data to the handle, if possible. This avoids having to register
		268	a write watcher and wait for the next event loop iteration, but can
		269	be inefficient if you write multiple small chunks (on the wire, this
		270	disadvantage is usually avoided by your kernel's nagle algorithm, see
		271	C<no_delay>, but this option can save costly syscalls).
		272
		273	When enabled, then writes will always be queued till the next event loop
		274	iteration. This is efficient when you do many small writes per iteration,
		275	but less efficient when you do a single write only per iteration (or when
		276	the write buffer often is full). It also increases write latency.
		277
		278	=item no_delay => <boolean>
		279
		280	When doing small writes on sockets, your operating system kernel might
		281	wait a bit for more data before actually sending it out. This is called
		282	the Nagle algorithm, and usually it is beneficial.
		283
		284	In some situations you want as low a delay as possible, which can be
		285	accomplishd by setting this option to a true value.
		286
		287	The default is your opertaing system's default behaviour (most likely
		288	enabled), this option explicitly enables or disables it, if possible.
		289
127	=item read_size => <bytes>	290	=item read_size => <bytes>
128		291
129	The default read block size (the amount of bytes this module will try to read	292	The default read block size (the amount of bytes this module will
130	on each [loop iteration). Default: C<4096>.	293	try to read during each loop iteration, which affects memory
		294	requirements). Default: C<8192>.
131		295
132	=item low_water_mark => <bytes>	296	=item low_water_mark => <bytes>
133		297
134	Sets the amount of bytes (default: C<0>) that make up an "empty" write	298	Sets the amount of bytes (default: C<0>) that make up an "empty" write
135	buffer: If the write reaches this size or gets even samller it is	299	buffer: If the write reaches this size or gets even samller it is
136	considered empty.	300	considered empty.
137		301
		302	Sometimes it can be beneficial (for performance reasons) to add data to
		303	the write buffer before it is fully drained, but this is a rare case, as
		304	the operating system kernel usually buffers data as well, so the default
		305	is good in almost all cases.
		306
		307	=item linger => <seconds>
		308
		309	If non-zero (default: C<3600>), then the destructor of the
		310	AnyEvent::Handle object will check whether there is still outstanding
		311	write data and will install a watcher that will write this data to the
		312	socket. No errors will be reported (this mostly matches how the operating
		313	system treats outstanding data at socket close time).
		314
		315	This will not work for partial TLS data that could not be encoded
		316	yet. This data will be lost. Calling the C<stoptls> method in time might
		317	help.
		318
		319	=item peername => $string
		320
		321	A string used to identify the remote site - usually the DNS hostname
		322	(I<not> IDN!) used to create the connection, rarely the IP address.
		323
		324	Apart from being useful in error messages, this string is also used in TLS
		325	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		326	verification will be skipped when C<peername> is not specified or
		327	C<undef>.
		328
		329	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
		330
		331	When this parameter is given, it enables TLS (SSL) mode, that means
		332	AnyEvent will start a TLS handshake as soon as the conenction has been
		333	established and will transparently encrypt/decrypt data afterwards.
		334
		335	All TLS protocol errors will be signalled as C<EPROTO>, with an
		336	appropriate error message.
		337
		338	TLS mode requires Net::SSLeay to be installed (it will be loaded
		339	automatically when you try to create a TLS handle): this module doesn't
		340	have a dependency on that module, so if your module requires it, you have
		341	to add the dependency yourself.
		342
		343	Unlike TCP, TLS has a server and client side: for the TLS server side, use
		344	C<accept>, and for the TLS client side of a connection, use C<connect>
		345	mode.
		346
		347	You can also provide your own TLS connection object, but you have
		348	to make sure that you call either C<Net::SSLeay::set_connect_state>
		349	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		350	AnyEvent::Handle. Also, this module will take ownership of this connection
		351	object.
		352
		353	At some future point, AnyEvent::Handle might switch to another TLS
		354	implementation, then the option to use your own session object will go
		355	away.
		356
		357	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		358	passing in the wrong integer will lead to certain crash. This most often
		359	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		360	segmentation fault.
		361
		362	See the C<< ->starttls >> method for when need to start TLS negotiation later.
		363
		364	=item tls_ctx => $anyevent_tls
		365
		366	Use the given C<AnyEvent::TLS> object to create the new TLS connection
		367	(unless a connection object was specified directly). If this parameter is
		368	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		369
		370	Instead of an object, you can also specify a hash reference with C<< key
		371	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		372	new TLS context object.
		373
		374	=item on_starttls => $cb->($handle, $success[, $error_message])
		375
		376	This callback will be invoked when the TLS/SSL handshake has finished. If
		377	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		378	(C<on_stoptls> will not be called in this case).
		379
		380	The session in C<< $handle->{tls} >> can still be examined in this
		381	callback, even when the handshake was not successful.
		382
		383	TLS handshake failures will not cause C<on_error> to be invoked when this
		384	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		385
		386	Without this callback, handshake failures lead to C<on_error> being
		387	called, as normal.
		388
		389	Note that you cannot call C<starttls> right again in this callback. If you
		390	need to do that, start an zero-second timer instead whose callback can
		391	then call C<< ->starttls >> again.
		392
		393	=item on_stoptls => $cb->($handle)
		394
		395	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		396	set, then it will be invoked after freeing the TLS session. If it is not,
		397	then a TLS shutdown condition will be treated like a normal EOF condition
		398	on the handle.
		399
		400	The session in C<< $handle->{tls} >> can still be examined in this
		401	callback.
		402
		403	This callback will only be called on TLS shutdowns, not when the
		404	underlying handle signals EOF.
		405
		406	=item json => JSON or JSON::XS object
		407
		408	This is the json coder object used by the C<json> read and write types.
		409
		410	If you don't supply it, then AnyEvent::Handle will create and use a
		411	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		412	texts.
		413
		414	Note that you are responsible to depend on the JSON module if you want to
		415	use this functionality, as AnyEvent does not have a dependency itself.
		416
138	=back	417	=back
139		418
140	=cut	419	=cut
141		420
142	sub new {	421	sub new {
143	my $class = shift;	422	my $class = shift;
144
145	my $self = bless { @_ }, $class;	423	my $self = bless { @_ }, $class;
146		424
147	$self->{fh} or Carp::croak "mandatory argument fh is missing";	425	if ($self->{fh}) {
		426	$self->_start;
		427	return unless $self->{fh}; # could be gone by now
		428
		429	} elsif ($self->{connect}) {
		430	require AnyEvent::Socket;
		431
		432	$self->{peername} = $self->{connect}[0]
		433	unless exists $self->{peername};
		434
		435	$self->{_skip_drain_rbuf} = 1;
		436
		437	{
		438	Scalar::Util::weaken (my $self = $self);
		439
		440	$self->{_connect} =
		441	AnyEvent::Socket::tcp_connect (
		442	$self->{connect}[0],
		443	$self->{connect}[1],
		444	sub {
		445	my ($fh, $host, $port, $retry) = @_;
		446
		447	if ($fh) {
		448	$self->{fh} = $fh;
		449
		450	delete $self->{_skip_drain_rbuf};
		451	$self->_start;
		452
		453	$self->{on_connect}
		454	and $self->{on_connect}($self, $host, $port, sub {
		455	delete @$self{qw(fh _tw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		456	$self->{_skip_drain_rbuf} = 1;
		457	&$retry;
		458	});
		459
		460	} else {
		461	if ($self->{on_connect_error}) {
		462	$self->{on_connect_error}($self, "$!");
		463	$self->destroy;
		464	} else {
		465	$self->_error ($!, 1);
		466	}
		467	}
		468	},
		469	sub {
		470	local $self->{fh} = $_[0];
		471
		472	$self->{on_prepare}
		473	? $self->{on_prepare}->($self)
		474	: ()
		475	}
		476	);
		477	}
		478
		479	} else {
		480	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		481	}
		482
		483	$self
		484	}
		485
		486	sub _start {
		487	my ($self) = @_;
148		488
149	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	489	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
150		490
151	$self->on_eof ((delete $self->{on_eof} ) or Carp::croak "mandatory argument on_eof is missing");	491	$self->{_activity} =
		492	$self->{_ractivity} =
		493	$self->{_wactivity} = AE::now;
152		494
153	$self->on_error (delete $self->{on_error}) if $self->{on_error};	495	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		496	$self->rtimeout (delete $self->{rtimeout}) if $self->{rtimeout};
		497	$self->wtimeout (delete $self->{wtimeout}) if $self->{wtimeout};
		498
		499	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
		500
		501	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
		502	if $self->{tls};
		503
154	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	504	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
155	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
156		505
157	$self->start_read;	506	$self->start_read
		507	if $self->{on_read} || @{ $self->{_queue} };
158		508
159	$self	509	$self->_drain_wbuf;
160	}	510	}
161		511
162	sub _shutdown {	512	#sub _shutdown {
163	my ($self) = @_;	513	# my ($self) = @_;
		514	#
		515	# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
		516	# $self->{_eof} = 1; # tell starttls et. al to stop trying
		517	#
		518	# &_freetls;
		519	#}
164		520
165	delete $self->{rw};
166	delete $self->{ww};
167	delete $self->{fh};
168	}
169
170	sub error {	521	sub _error {
171	my ($self) = @_;	522	my ($self, $errno, $fatal, $message) = @_;
172		523
173	{	524	$! = $errno;
174	local $!;	525	$message ||= "$!";
175	$self->_shutdown;
176	}
177		526
178	if ($self->{on_error}) {	527	if ($self->{on_error}) {
179	$self->{on_error}($self);	528	$self->{on_error}($self, $fatal, $message);
180	} else {	529	$self->destroy if $fatal;
		530	} elsif ($self->{fh}) {
		531	$self->destroy;
181	die "AnyEvent::Handle uncaught fatal error: $!";	532	Carp::croak "AnyEvent::Handle uncaught error: $message";
182	}	533	}
183	}	534	}
184		535
185	=item $fh = $handle->fh	536	=item $fh = $handle->fh
186		537
187	This method returns the filehandle of the L<AnyEvent::Handle> object.	538	This method returns the file handle used to create the L<AnyEvent::Handle> object.
188		539
189	=cut	540	=cut
190		541
191	sub fh { $_[0]->{fh} }	542	sub fh { $_[0]{fh} }
192		543
193	=item $handle->on_error ($cb)	544	=item $handle->on_error ($cb)
194		545
195	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	546	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
196		547
…		…
208		559
209	sub on_eof {	560	sub on_eof {
210	$_[0]{on_eof} = $_[1];	561	$_[0]{on_eof} = $_[1];
211	}	562	}
212		563
		564	=item $handle->on_timeout ($cb)
		565
		566	=item $handle->on_rtimeout ($cb)
		567
		568	=item $handle->on_wtimeout ($cb)
		569
		570	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		571	callback, or disables the callback (but not the timeout) if C<$cb> =
		572	C<undef>. See the C<timeout> constructor argument and method.
		573
		574	=cut
		575
		576	# see below
		577
		578	=item $handle->autocork ($boolean)
		579
		580	Enables or disables the current autocork behaviour (see C<autocork>
		581	constructor argument). Changes will only take effect on the next write.
		582
		583	=cut
		584
		585	sub autocork {
		586	$_[0]{autocork} = $_[1];
		587	}
		588
		589	=item $handle->no_delay ($boolean)
		590
		591	Enables or disables the C<no_delay> setting (see constructor argument of
		592	the same name for details).
		593
		594	=cut
		595
		596	sub no_delay {
		597	$_[0]{no_delay} = $_[1];
		598
		599	eval {
		600	local $SIG{__DIE__};
		601	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]
		602	if $_[0]{fh};
		603	};
		604	}
		605
		606	=item $handle->on_starttls ($cb)
		607
		608	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		609
		610	=cut
		611
		612	sub on_starttls {
		613	$_[0]{on_starttls} = $_[1];
		614	}
		615
		616	=item $handle->on_stoptls ($cb)
		617
		618	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		619
		620	=cut
		621
		622	sub on_starttls {
		623	$_[0]{on_stoptls} = $_[1];
		624	}
		625
		626	=item $handle->rbuf_max ($max_octets)
		627
		628	Configures the C<rbuf_max> setting (C<undef> disables it).
		629
		630	=cut
		631
		632	sub rbuf_max {
		633	$_[0]{rbuf_max} = $_[1];
		634	}
		635
		636	#############################################################################
		637
		638	=item $handle->timeout ($seconds)
		639
		640	=item $handle->rtimeout ($seconds)
		641
		642	=item $handle->wtimeout ($seconds)
		643
		644	Configures (or disables) the inactivity timeout.
		645
		646	=item $handle->timeout_reset
		647
		648	=item $handle->rtimeout_reset
		649
		650	=item $handle->wtimeout_reset
		651
		652	Reset the activity timeout, as if data was received or sent.
		653
		654	These methods are cheap to call.
		655
		656	=cut
		657
		658	for my $dir ("", "r", "w") {
		659	my $timeout = "${dir}timeout";
		660	my $tw = "_${dir}tw";
		661	my $on_timeout = "on_${dir}timeout";
		662	my $activity = "_${dir}activity";
		663	my $cb;
		664
		665	*$on_timeout = sub {
		666	$_[0]{$on_timeout} = $_[1];
		667	};
		668
		669	*$timeout = sub {
		670	my ($self, $new_value) = @_;
		671
		672	$self->{$timeout} = $new_value;
		673	delete $self->{$tw}; &$cb;
		674	};
		675
		676	*{"${dir}timeout_reset"} = sub {
		677	$_[0]{$activity} = AE::now;
		678	};
		679
		680	# main workhorse:
		681	# reset the timeout watcher, as neccessary
		682	# also check for time-outs
		683	$cb = sub {
		684	my ($self) = @_;
		685
		686	if ($self->{$timeout} && $self->{fh}) {
		687	my $NOW = AE::now;
		688
		689	# when would the timeout trigger?
		690	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		691
		692	# now or in the past already?
		693	if ($after <= 0) {
		694	$self->{$activity} = $NOW;
		695
		696	if ($self->{$on_timeout}) {
		697	$self->{$on_timeout}($self);
		698	} else {
		699	$self->_error (Errno::ETIMEDOUT);
		700	}
		701
		702	# callback could have changed timeout value, optimise
		703	return unless $self->{$timeout};
		704
		705	# calculate new after
		706	$after = $self->{$timeout};
		707	}
		708
		709	Scalar::Util::weaken $self;
		710	return unless $self; # ->error could have destroyed $self
		711
		712	$self->{$tw} ||= AE::timer $after, 0, sub {
		713	delete $self->{$tw};
		714	$cb->($self);
		715	};
		716	} else {
		717	delete $self->{$tw};
		718	}
		719	}
		720	}
		721
213	#############################################################################	722	#############################################################################
214		723
215	=back	724	=back
216		725
217	=head2 WRITE QUEUE	726	=head2 WRITE QUEUE
…		…
220	for reading.	729	for reading.
221		730
222	The write queue is very simple: you can add data to its end, and	731	The write queue is very simple: you can add data to its end, and
223	AnyEvent::Handle will automatically try to get rid of it for you.	732	AnyEvent::Handle will automatically try to get rid of it for you.
224		733
225	When data could be writtena nd the write buffer is shorter then the low	734	When data could be written and the write buffer is shorter then the low
226	water mark, the C<on_drain> callback will be invoked.	735	water mark, the C<on_drain> callback will be invoked.
227		736
228	=over 4	737	=over 4
229		738
230	=item $handle->on_drain ($cb)	739	=item $handle->on_drain ($cb)
…		…
238	my ($self, $cb) = @_;	747	my ($self, $cb) = @_;
239		748
240	$self->{on_drain} = $cb;	749	$self->{on_drain} = $cb;
241		750
242	$cb->($self)	751	$cb->($self)
243	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	752	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
244	}	753	}
245		754
246	=item $handle->push_write ($data)	755	=item $handle->push_write ($data)
247		756
248	Queues the given scalar to be written. You can push as much data as you	757	Queues the given scalar to be written. You can push as much data as you
249	want (only limited by the available memory), as C<AnyEvent::Handle>	758	want (only limited by the available memory), as C<AnyEvent::Handle>
250	buffers it independently of the kernel.	759	buffers it independently of the kernel.
251		760
252	=cut	761	=cut
253		762
254	sub push_write {	763	sub _drain_wbuf {
255	my ($self, $data) = @_;	764	my ($self) = @_;
256		765
257	$self->{wbuf} .= $data;	766	if (!$self->{_ww} && length $self->{wbuf}) {
258		767
259	unless ($self->{ww}) {
260	Scalar::Util::weaken $self;	768	Scalar::Util::weaken $self;
		769
261	my $cb = sub {	770	my $cb = sub {
262	my $len = syswrite $self->{fh}, $self->{wbuf};	771	my $len = syswrite $self->{fh}, $self->{wbuf};
263		772
264	if ($len > 0) {	773	if (defined $len) {
265	substr $self->{wbuf}, 0, $len, "";	774	substr $self->{wbuf}, 0, $len, "";
266		775
		776	$self->{_activity} = $self->{_wactivity} = AE::now;
267		777
268	$self->{on_drain}($self)	778	$self->{on_drain}($self)
269	if $self->{low_water_mark} >= length $self->{wbuf}	779	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
270	&& $self->{on_drain};	780	&& $self->{on_drain};
271		781
272	delete $self->{ww} unless length $self->{wbuf};	782	delete $self->{_ww} unless length $self->{wbuf};
273	} elsif ($! != EAGAIN && $! != EINTR) {	783	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
274	$self->error;	784	$self->_error ($!, 1);
275	}	785	}
276	};	786	};
277		787
278	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	788	# try to write data immediately
		789	$cb->() unless $self->{autocork};
279		790
280	$cb->($self);	791	# if still data left in wbuf, we need to poll
		792	$self->{_ww} = AE::io $self->{fh}, 1, $cb
		793	if length $self->{wbuf};
281	};	794	};
282	}	795	}
		796
		797	our %WH;
		798
		799	sub register_write_type($$) {
		800	$WH{$_[0]} = $_[1];
		801	}
		802
		803	sub push_write {
		804	my $self = shift;
		805
		806	if (@_ > 1) {
		807	my $type = shift;
		808
		809	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		810	->($self, @_);
		811	}
		812
		813	if ($self->{tls}) {
		814	$self->{_tls_wbuf} .= $_[0];
		815	&_dotls ($self) if $self->{fh};
		816	} else {
		817	$self->{wbuf} .= $_[0];
		818	$self->_drain_wbuf if $self->{fh};
		819	}
		820	}
		821
		822	=item $handle->push_write (type => @args)
		823
		824	Instead of formatting your data yourself, you can also let this module do
		825	the job by specifying a type and type-specific arguments.
		826
		827	Predefined types are (if you have ideas for additional types, feel free to
		828	drop by and tell us):
		829
		830	=over 4
		831
		832	=item netstring => $string
		833
		834	Formats the given value as netstring
		835	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		836
		837	=cut
		838
		839	register_write_type netstring => sub {
		840	my ($self, $string) = @_;
		841
		842	(length $string) . ":$string,"
		843	};
		844
		845	=item packstring => $format, $data
		846
		847	An octet string prefixed with an encoded length. The encoding C<$format>
		848	uses the same format as a Perl C<pack> format, but must specify a single
		849	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		850	optional C<!>, C<< < >> or C<< > >> modifier).
		851
		852	=cut
		853
		854	register_write_type packstring => sub {
		855	my ($self, $format, $string) = @_;
		856
		857	pack "$format/a*", $string
		858	};
		859
		860	=item json => $array_or_hashref
		861
		862	Encodes the given hash or array reference into a JSON object. Unless you
		863	provide your own JSON object, this means it will be encoded to JSON text
		864	in UTF-8.
		865
		866	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		867	one end of a handle and read them at the other end without using any
		868	additional framing.
		869
		870	The generated JSON text is guaranteed not to contain any newlines: While
		871	this module doesn't need delimiters after or between JSON texts to be
		872	able to read them, many other languages depend on that.
		873
		874	A simple RPC protocol that interoperates easily with others is to send
		875	JSON arrays (or objects, although arrays are usually the better choice as
		876	they mimic how function argument passing works) and a newline after each
		877	JSON text:
		878
		879	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		880	$handle->push_write ("\012");
		881
		882	An AnyEvent::Handle receiver would simply use the C<json> read type and
		883	rely on the fact that the newline will be skipped as leading whitespace:
		884
		885	$handle->push_read (json => sub { my $array = $_[1]; ... });
		886
		887	Other languages could read single lines terminated by a newline and pass
		888	this line into their JSON decoder of choice.
		889
		890	=cut
		891
		892	register_write_type json => sub {
		893	my ($self, $ref) = @_;
		894
		895	require JSON;
		896
		897	$self->{json} ? $self->{json}->encode ($ref)
		898	: JSON::encode_json ($ref)
		899	};
		900
		901	=item storable => $reference
		902
		903	Freezes the given reference using L<Storable> and writes it to the
		904	handle. Uses the C<nfreeze> format.
		905
		906	=cut
		907
		908	register_write_type storable => sub {
		909	my ($self, $ref) = @_;
		910
		911	require Storable;
		912
		913	pack "w/a*", Storable::nfreeze ($ref)
		914	};
		915
		916	=back
		917
		918	=item $handle->push_shutdown
		919
		920	Sometimes you know you want to close the socket after writing your data
		921	before it was actually written. One way to do that is to replace your
		922	C<on_drain> handler by a callback that shuts down the socket (and set
		923	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		924	replaces the C<on_drain> callback with:
		925
		926	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		927
		928	This simply shuts down the write side and signals an EOF condition to the
		929	the peer.
		930
		931	You can rely on the normal read queue and C<on_eof> handling
		932	afterwards. This is the cleanest way to close a connection.
		933
		934	=cut
		935
		936	sub push_shutdown {
		937	my ($self) = @_;
		938
		939	delete $self->{low_water_mark};
		940	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		941	}
		942
		943	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		944
		945	This function (not method) lets you add your own types to C<push_write>.
		946	Whenever the given C<type> is used, C<push_write> will invoke the code
		947	reference with the handle object and the remaining arguments.
		948
		949	The code reference is supposed to return a single octet string that will
		950	be appended to the write buffer.
		951
		952	Note that this is a function, and all types registered this way will be
		953	global, so try to use unique names.
		954
		955	=cut
283		956
284	#############################################################################	957	#############################################################################
285		958
286	=back	959	=back
287		960
…		…
294	ways, the "simple" way, using only C<on_read> and the "complex" way, using	967	ways, the "simple" way, using only C<on_read> and the "complex" way, using
295	a queue.	968	a queue.
296		969
297	In the simple case, you just install an C<on_read> callback and whenever	970	In the simple case, you just install an C<on_read> callback and whenever
298	new data arrives, it will be called. You can then remove some data (if	971	new data arrives, it will be called. You can then remove some data (if
299	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	972	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
300	or not.	973	leave the data there if you want to accumulate more (e.g. when only a
		974	partial message has been received so far).
301		975
302	In the more complex case, you want to queue multiple callbacks. In this	976	In the more complex case, you want to queue multiple callbacks. In this
303	case, AnyEvent::Handle will call the first queued callback each time new	977	case, AnyEvent::Handle will call the first queued callback each time new
304	data arrives and removes it when it has done its job (see C<push_read>,	978	data arrives (also the first time it is queued) and removes it when it has
305	below).	979	done its job (see C<push_read>, below).
306		980
307	This way you can, for example, push three line-reads, followed by reading	981	This way you can, for example, push three line-reads, followed by reading
308	a chunk of data, and AnyEvent::Handle will execute them in order.	982	a chunk of data, and AnyEvent::Handle will execute them in order.
309		983
310	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	984	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
311	the specified number of bytes which give an XML datagram.	985	the specified number of bytes which give an XML datagram.
312		986
313	# in the default state, expect some header bytes	987	# in the default state, expect some header bytes
314	$handle->on_read (sub {	988	$handle->on_read (sub {
315	# some data is here, now queue the length-header-read (4 octets)	989	# some data is here, now queue the length-header-read (4 octets)
316	shift->unshift_read_chunk (4, sub {	990	shift->unshift_read (chunk => 4, sub {
317	# header arrived, decode	991	# header arrived, decode
318	my $len = unpack "N", $_[1];	992	my $len = unpack "N", $_[1];
319		993
320	# now read the payload	994	# now read the payload
321	shift->unshift_read_chunk ($len, sub {	995	shift->unshift_read (chunk => $len, sub {
322	my $xml = $_[1];	996	my $xml = $_[1];
323	# handle xml	997	# handle xml
324	});	998	});
325	});	999	});
326	});	1000	});
327		1001
328	Example 2: Implement a client for a protocol that replies either with	1002	Example 2: Implement a client for a protocol that replies either with "OK"
329	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1003	and another line or "ERROR" for the first request that is sent, and 64
330	second request. Due tot he availability of a full queue, we can just	1004	bytes for the second request. Due to the availability of a queue, we can
331	pipeline sending both requests and manipulate the queue as necessary in	1005	just pipeline sending both requests and manipulate the queue as necessary
332	the callbacks:	1006	in the callbacks.
333		1007
334	# request one	1008	When the first callback is called and sees an "OK" response, it will
		1009	C<unshift> another line-read. This line-read will be queued I<before> the
		1010	64-byte chunk callback.
		1011
		1012	# request one, returns either "OK + extra line" or "ERROR"
335	$handle->push_write ("request 1\015\012");	1013	$handle->push_write ("request 1\015\012");
336		1014
337	# we expect "ERROR" or "OK" as response, so push a line read	1015	# we expect "ERROR" or "OK" as response, so push a line read
338	$handle->push_read_line (sub {	1016	$handle->push_read (line => sub {
339	# if we got an "OK", we have to _prepend_ another line,	1017	# if we got an "OK", we have to _prepend_ another line,
340	# so it will be read before the second request reads its 64 bytes	1018	# so it will be read before the second request reads its 64 bytes
341	# which are already in the queue when this callback is called	1019	# which are already in the queue when this callback is called
342	# we don't do this in case we got an error	1020	# we don't do this in case we got an error
343	if ($_[1] eq "OK") {	1021	if ($_[1] eq "OK") {
344	$_[0]->unshift_read_line (sub {	1022	$_[0]->unshift_read (line => sub {
345	my $response = $_[1];	1023	my $response = $_[1];
346	...	1024	...
347	});	1025	});
348	}	1026	}
349	});	1027	});
350		1028
351	# request two	1029	# request two, simply returns 64 octets
352	$handle->push_write ("request 2\015\012");	1030	$handle->push_write ("request 2\015\012");
353		1031
354	# simply read 64 bytes, always	1032	# simply read 64 bytes, always
355	$handle->push_read_chunk (64, sub {	1033	$handle->push_read (chunk => 64, sub {
356	my $response = $_[1];	1034	my $response = $_[1];
357	...	1035	...
358	});	1036	});
359		1037
360	=over 4	1038	=over 4
…		…
362	=cut	1040	=cut
363		1041
364	sub _drain_rbuf {	1042	sub _drain_rbuf {
365	my ($self) = @_;	1043	my ($self) = @_;
366		1044
		1045	# avoid recursion
367	return if $self->{in_drain};	1046	return if $self->{_skip_drain_rbuf};
368	local $self->{in_drain} = 1;	1047	local $self->{_skip_drain_rbuf} = 1;
369		1048
		1049	while () {
		1050	# we need to use a separate tls read buffer, as we must not receive data while
		1051	# we are draining the buffer, and this can only happen with TLS.
		1052	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1053	if exists $self->{_tls_rbuf};
		1054
370	while (my $len = length $self->{rbuf}) {	1055	my $len = length $self->{rbuf};
371	no strict 'refs';	1056
372	if (my $cb = shift @{ $self->{queue} }) {	1057	if (my $cb = shift @{ $self->{_queue} }) {
373	if (!$cb->($self)) {	1058	unless ($cb->($self)) {
		1059	# no progress can be made
		1060	# (not enough data and no data forthcoming)
		1061	$self->_error (Errno::EPIPE, 1), return
374	if ($self->{eof}) {	1062	if $self->{_eof};
375	# no progress can be made (not enough data and no data forthcoming)
376	$! = &Errno::EPIPE; return $self->error;
377	}
378		1063
379	unshift @{ $self->{queue} }, $cb;	1064	unshift @{ $self->{_queue} }, $cb;
380	return;	1065	last;
381	}	1066	}
382	} elsif ($self->{on_read}) {	1067	} elsif ($self->{on_read}) {
		1068	last unless $len;
		1069
383	$self->{on_read}($self);	1070	$self->{on_read}($self);
384		1071
385	if (	1072	if (
386	$self->{eof} # if no further data will arrive
387	&& $len == length $self->{rbuf} # and no data has been consumed	1073	$len == length $self->{rbuf} # if no data has been consumed
388	&& !@{ $self->{queue} } # and the queue is still empty	1074	&& !@{ $self->{_queue} } # and the queue is still empty
389	&& $self->{on_read} # and we still want to read data	1075	&& $self->{on_read} # but we still have on_read
390	) {	1076	) {
		1077	# no further data will arrive
391	# then no progress can be made	1078	# so no progress can be made
392	$! = &Errno::EPIPE; return $self->error;	1079	$self->_error (Errno::EPIPE, 1), return
		1080	if $self->{_eof};
		1081
		1082	last; # more data might arrive
393	}	1083	}
394	} else {	1084	} else {
395	# read side becomes idle	1085	# read side becomes idle
396	delete $self->{rw};	1086	delete $self->{_rw} unless $self->{tls};
397	return;	1087	last;
398	}	1088	}
399	}	1089	}
400		1090
401	if ($self->{eof}) {	1091	if ($self->{_eof}) {
402	$self->_shutdown;	1092	$self->{on_eof}
403	$self->{on_eof}($self);	1093	? $self->{on_eof}($self)
		1094	: $self->_error (0, 1, "Unexpected end-of-file");
		1095
		1096	return;
		1097	}
		1098
		1099	if (
		1100	defined $self->{rbuf_max}
		1101	&& $self->{rbuf_max} < length $self->{rbuf}
		1102	) {
		1103	$self->_error (Errno::ENOSPC, 1), return;
		1104	}
		1105
		1106	# may need to restart read watcher
		1107	unless ($self->{_rw}) {
		1108	$self->start_read
		1109	if $self->{on_read} || @{ $self->{_queue} };
404	}	1110	}
405	}	1111	}
406		1112
407	=item $handle->on_read ($cb)	1113	=item $handle->on_read ($cb)
408		1114
…		…
414		1120
415	sub on_read {	1121	sub on_read {
416	my ($self, $cb) = @_;	1122	my ($self, $cb) = @_;
417		1123
418	$self->{on_read} = $cb;	1124	$self->{on_read} = $cb;
		1125	$self->_drain_rbuf if $cb;
419	}	1126	}
420		1127
421	=item $handle->rbuf	1128	=item $handle->rbuf
422		1129
423	Returns the read buffer (as a modifiable lvalue).	1130	Returns the read buffer (as a modifiable lvalue).
424		1131
425	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1132	You can access the read buffer directly as the C<< ->{rbuf} >>
426	you want.	1133	member, if you want. However, the only operation allowed on the
		1134	read buffer (apart from looking at it) is removing data from its
		1135	beginning. Otherwise modifying or appending to it is not allowed and will
		1136	lead to hard-to-track-down bugs.
427		1137
428	NOTE: The read buffer should only be used or modified if the C<on_read>,	1138	NOTE: The read buffer should only be used or modified if the C<on_read>,
429	C<push_read> or C<unshift_read> methods are used. The other read methods	1139	C<push_read> or C<unshift_read> methods are used. The other read methods
430	automatically manage the read buffer.	1140	automatically manage the read buffer.
431		1141
…		…
442	Append the given callback to the end of the queue (C<push_read>) or	1152	Append the given callback to the end of the queue (C<push_read>) or
443	prepend it (C<unshift_read>).	1153	prepend it (C<unshift_read>).
444		1154
445	The callback is called each time some additional read data arrives.	1155	The callback is called each time some additional read data arrives.
446		1156
447	It must check wether enough data is in the read buffer already.	1157	It must check whether enough data is in the read buffer already.
448		1158
449	If not enough data is available, it must return the empty list or a false	1159	If not enough data is available, it must return the empty list or a false
450	value, in which case it will be called repeatedly until enough data is	1160	value, in which case it will be called repeatedly until enough data is
451	available (or an error condition is detected).	1161	available (or an error condition is detected).
452		1162
…		…
454	interested in (which can be none at all) and return a true value. After returning	1164	interested in (which can be none at all) and return a true value. After returning
455	true, it will be removed from the queue.	1165	true, it will be removed from the queue.
456		1166
457	=cut	1167	=cut
458		1168
		1169	our %RH;
		1170
		1171	sub register_read_type($$) {
		1172	$RH{$_[0]} = $_[1];
		1173	}
		1174
459	sub push_read {	1175	sub push_read {
460	my ($self, $cb) = @_;	1176	my $self = shift;
		1177	my $cb = pop;
461		1178
		1179	if (@_) {
		1180	my $type = shift;
		1181
		1182	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		1183	->($self, $cb, @_);
		1184	}
		1185
462	push @{ $self->{queue} }, $cb;	1186	push @{ $self->{_queue} }, $cb;
463	$self->_drain_rbuf;	1187	$self->_drain_rbuf;
464	}	1188	}
465		1189
466	sub unshift_read {	1190	sub unshift_read {
467	my ($self, $cb) = @_;	1191	my $self = shift;
		1192	my $cb = pop;
468		1193
		1194	if (@_) {
		1195	my $type = shift;
		1196
		1197	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		1198	->($self, $cb, @_);
		1199	}
		1200
		1201
469	push @{ $self->{queue} }, $cb;	1202	unshift @{ $self->{_queue} }, $cb;
470	$self->_drain_rbuf;	1203	$self->_drain_rbuf;
471	}	1204	}
472		1205
473	=item $handle->push_read_chunk ($len, $cb->($self, $data))	1206	=item $handle->push_read (type => @args, $cb)
474		1207
475	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	1208	=item $handle->unshift_read (type => @args, $cb)
476		1209
477	Append the given callback to the end of the queue (C<push_read_chunk>) or	1210	Instead of providing a callback that parses the data itself you can chose
478	prepend it (C<unshift_read_chunk>).	1211	between a number of predefined parsing formats, for chunks of data, lines
		1212	etc.
479		1213
480	The callback will be called only once C<$len> bytes have been read, and	1214	Predefined types are (if you have ideas for additional types, feel free to
481	these C<$len> bytes will be passed to the callback.	1215	drop by and tell us):
482		1216
483	=cut	1217	=over 4
484		1218
485	sub _read_chunk($$) {	1219	=item chunk => $octets, $cb->($handle, $data)
		1220
		1221	Invoke the callback only once C<$octets> bytes have been read. Pass the
		1222	data read to the callback. The callback will never be called with less
		1223	data.
		1224
		1225	Example: read 2 bytes.
		1226
		1227	$handle->push_read (chunk => 2, sub {
		1228	warn "yay ", unpack "H*", $_[1];
		1229	});
		1230
		1231	=cut
		1232
		1233	register_read_type chunk => sub {
486	my ($self, $len, $cb) = @_;	1234	my ($self, $cb, $len) = @_;
487		1235
488	sub {	1236	sub {
489	$len <= length $_[0]{rbuf} or return;	1237	$len <= length $_[0]{rbuf} or return;
490	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1238	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
491	1	1239	1
492	}	1240	}
493	}	1241	};
494		1242
495	sub push_read_chunk {	1243	=item line => [$eol, ]$cb->($handle, $line, $eol)
496	$_[0]->push_read (&_read_chunk);
497	}
498
499
500	sub unshift_read_chunk {
501	$_[0]->unshift_read (&_read_chunk);
502	}
503
504	=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
505
506	=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
507
508	Append the given callback to the end of the queue (C<push_read_line>) or
509	prepend it (C<unshift_read_line>).
510		1244
511	The callback will be called only once a full line (including the end of	1245	The callback will be called only once a full line (including the end of
512	line marker, C<$eol>) has been read. This line (excluding the end of line	1246	line marker, C<$eol>) has been read. This line (excluding the end of line
513	marker) will be passed to the callback as second argument (C<$line>), and	1247	marker) will be passed to the callback as second argument (C<$line>), and
514	the end of line marker as the third argument (C<$eol>).	1248	the end of line marker as the third argument (C<$eol>).
…		…
525	Partial lines at the end of the stream will never be returned, as they are	1259	Partial lines at the end of the stream will never be returned, as they are
526	not marked by the end of line marker.	1260	not marked by the end of line marker.
527		1261
528	=cut	1262	=cut
529		1263
530	sub _read_line($$) {	1264	register_read_type line => sub {
531	my $self = shift;	1265	my ($self, $cb, $eol) = @_;
532	my $cb = pop;
533	my $eol = @_ ? shift : qr|(\015?\012)|;
534	my $pos;
535		1266
		1267	if (@_ < 3) {
		1268	# this is more than twice as fast as the generic code below
		1269	sub {
		1270	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		1271
		1272	$cb->($_[0], $1, $2);
		1273	1
		1274	}
		1275	} else {
536	$eol = quotemeta $eol unless ref $eol;	1276	$eol = quotemeta $eol unless ref $eol;
537	$eol = qr|^(.*?)($eol)|s;	1277	$eol = qr|^(.*?)($eol)|s;
		1278
		1279	sub {
		1280	$_[0]{rbuf} =~ s/$eol// or return;
		1281
		1282	$cb->($_[0], $1, $2);
		1283	1
		1284	}
		1285	}
		1286	};
		1287
		1288	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1289
		1290	Makes a regex match against the regex object C<$accept> and returns
		1291	everything up to and including the match.
		1292
		1293	Example: read a single line terminated by '\n'.
		1294
		1295	$handle->push_read (regex => qr<\n>, sub { ... });
		1296
		1297	If C<$reject> is given and not undef, then it determines when the data is
		1298	to be rejected: it is matched against the data when the C<$accept> regex
		1299	does not match and generates an C<EBADMSG> error when it matches. This is
		1300	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1301	receive buffer overflow).
		1302
		1303	Example: expect a single decimal number followed by whitespace, reject
		1304	anything else (not the use of an anchor).
		1305
		1306	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1307
		1308	If C<$skip> is given and not C<undef>, then it will be matched against
		1309	the receive buffer when neither C<$accept> nor C<$reject> match,
		1310	and everything preceding and including the match will be accepted
		1311	unconditionally. This is useful to skip large amounts of data that you
		1312	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1313	have to start matching from the beginning. This is purely an optimisation
		1314	and is usually worth only when you expect more than a few kilobytes.
		1315
		1316	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1317	expect the header to be very large (it isn't in practise, but...), we use
		1318	a skip regex to skip initial portions. The skip regex is tricky in that
		1319	it only accepts something not ending in either \015 or \012, as these are
		1320	required for the accept regex.
		1321
		1322	$handle->push_read (regex =>
		1323	qr<\015\012\015\012>,
		1324	undef, # no reject
		1325	qr<^.*[^\015\012]>,
		1326	sub { ... });
		1327
		1328	=cut
		1329
		1330	register_read_type regex => sub {
		1331	my ($self, $cb, $accept, $reject, $skip) = @_;
		1332
		1333	my $data;
		1334	my $rbuf = \$self->{rbuf};
538		1335
539	sub {	1336	sub {
540	$_[0]{rbuf} =~ s/$eol// or return;	1337	# accept
		1338	if ($$rbuf =~ $accept) {
		1339	$data .= substr $$rbuf, 0, $+[0], "";
		1340	$cb->($self, $data);
		1341	return 1;
		1342	}
		1343
		1344	# reject
		1345	if ($reject && $$rbuf =~ $reject) {
		1346	$self->_error (Errno::EBADMSG);
		1347	}
541		1348
542	$cb->($_[0], $1, $2);	1349	# skip
		1350	if ($skip && $$rbuf =~ $skip) {
		1351	$data .= substr $$rbuf, 0, $+[0], "";
		1352	}
		1353
		1354	()
		1355	}
		1356	};
		1357
		1358	=item netstring => $cb->($handle, $string)
		1359
		1360	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1361
		1362	Throws an error with C<$!> set to EBADMSG on format violations.
		1363
		1364	=cut
		1365
		1366	register_read_type netstring => sub {
		1367	my ($self, $cb) = @_;
		1368
		1369	sub {
		1370	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1371	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1372	$self->_error (Errno::EBADMSG);
		1373	}
		1374	return;
		1375	}
		1376
		1377	my $len = $1;
		1378
		1379	$self->unshift_read (chunk => $len, sub {
		1380	my $string = $_[1];
		1381	$_[0]->unshift_read (chunk => 1, sub {
		1382	if ($_[1] eq ",") {
		1383	$cb->($_[0], $string);
		1384	} else {
		1385	$self->_error (Errno::EBADMSG);
		1386	}
		1387	});
		1388	});
		1389
543	1	1390	1
544	}	1391	}
545	}	1392	};
546		1393
547	sub push_read_line {	1394	=item packstring => $format, $cb->($handle, $string)
548	$_[0]->push_read (&_read_line);
549	}
550		1395
551	sub unshift_read_line {	1396	An octet string prefixed with an encoded length. The encoding C<$format>
552	$_[0]->unshift_read (&_read_line);	1397	uses the same format as a Perl C<pack> format, but must specify a single
553	}	1398	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1399	optional C<!>, C<< < >> or C<< > >> modifier).
		1400
		1401	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1402	EPP uses a prefix of C<N> (4 octtes).
		1403
		1404	Example: read a block of data prefixed by its length in BER-encoded
		1405	format (very efficient).
		1406
		1407	$handle->push_read (packstring => "w", sub {
		1408	my ($handle, $data) = @_;
		1409	});
		1410
		1411	=cut
		1412
		1413	register_read_type packstring => sub {
		1414	my ($self, $cb, $format) = @_;
		1415
		1416	sub {
		1417	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1418	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1419	or return;
		1420
		1421	$format = length pack $format, $len;
		1422
		1423	# bypass unshift if we already have the remaining chunk
		1424	if ($format + $len <= length $_[0]{rbuf}) {
		1425	my $data = substr $_[0]{rbuf}, $format, $len;
		1426	substr $_[0]{rbuf}, 0, $format + $len, "";
		1427	$cb->($_[0], $data);
		1428	} else {
		1429	# remove prefix
		1430	substr $_[0]{rbuf}, 0, $format, "";
		1431
		1432	# read remaining chunk
		1433	$_[0]->unshift_read (chunk => $len, $cb);
		1434	}
		1435
		1436	1
		1437	}
		1438	};
		1439
		1440	=item json => $cb->($handle, $hash_or_arrayref)
		1441
		1442	Reads a JSON object or array, decodes it and passes it to the
		1443	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1444
		1445	If a C<json> object was passed to the constructor, then that will be used
		1446	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1447
		1448	This read type uses the incremental parser available with JSON version
		1449	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1450	dependency on your own: this module will load the JSON module, but
		1451	AnyEvent does not depend on it itself.
		1452
		1453	Since JSON texts are fully self-delimiting, the C<json> read and write
		1454	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1455	the C<json> write type description, above, for an actual example.
		1456
		1457	=cut
		1458
		1459	register_read_type json => sub {
		1460	my ($self, $cb) = @_;
		1461
		1462	my $json = $self->{json} ||=
		1463	eval { require JSON::XS; JSON::XS->new->utf8 }
		1464	|| do { require JSON; JSON->new->utf8 };
		1465
		1466	my $data;
		1467	my $rbuf = \$self->{rbuf};
		1468
		1469	sub {
		1470	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
		1471
		1472	if ($ref) {
		1473	$self->{rbuf} = $json->incr_text;
		1474	$json->incr_text = "";
		1475	$cb->($self, $ref);
		1476
		1477	1
		1478	} elsif ($@) {
		1479	# error case
		1480	$json->incr_skip;
		1481
		1482	$self->{rbuf} = $json->incr_text;
		1483	$json->incr_text = "";
		1484
		1485	$self->_error (Errno::EBADMSG);
		1486
		1487	()
		1488	} else {
		1489	$self->{rbuf} = "";
		1490
		1491	()
		1492	}
		1493	}
		1494	};
		1495
		1496	=item storable => $cb->($handle, $ref)
		1497
		1498	Deserialises a L<Storable> frozen representation as written by the
		1499	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1500	data).
		1501
		1502	Raises C<EBADMSG> error if the data could not be decoded.
		1503
		1504	=cut
		1505
		1506	register_read_type storable => sub {
		1507	my ($self, $cb) = @_;
		1508
		1509	require Storable;
		1510
		1511	sub {
		1512	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1513	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1514	or return;
		1515
		1516	my $format = length pack "w", $len;
		1517
		1518	# bypass unshift if we already have the remaining chunk
		1519	if ($format + $len <= length $_[0]{rbuf}) {
		1520	my $data = substr $_[0]{rbuf}, $format, $len;
		1521	substr $_[0]{rbuf}, 0, $format + $len, "";
		1522	$cb->($_[0], Storable::thaw ($data));
		1523	} else {
		1524	# remove prefix
		1525	substr $_[0]{rbuf}, 0, $format, "";
		1526
		1527	# read remaining chunk
		1528	$_[0]->unshift_read (chunk => $len, sub {
		1529	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1530	$cb->($_[0], $ref);
		1531	} else {
		1532	$self->_error (Errno::EBADMSG);
		1533	}
		1534	});
		1535	}
		1536
		1537	1
		1538	}
		1539	};
		1540
		1541	=back
		1542
		1543	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1544
		1545	This function (not method) lets you add your own types to C<push_read>.
		1546
		1547	Whenever the given C<type> is used, C<push_read> will invoke the code
		1548	reference with the handle object, the callback and the remaining
		1549	arguments.
		1550
		1551	The code reference is supposed to return a callback (usually a closure)
		1552	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1553
		1554	It should invoke the passed callback when it is done reading (remember to
		1555	pass C<$handle> as first argument as all other callbacks do that).
		1556
		1557	Note that this is a function, and all types registered this way will be
		1558	global, so try to use unique names.
		1559
		1560	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1561	search for C<register_read_type>)).
554		1562
555	=item $handle->stop_read	1563	=item $handle->stop_read
556		1564
557	=item $handle->start_read	1565	=item $handle->start_read
558		1566
559	In rare cases you actually do not want to read anything form the	1567	In rare cases you actually do not want to read anything from the
560	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1568	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
561	any queued callbacks will be executed then. To start readign again, call	1569	any queued callbacks will be executed then. To start reading again, call
562	C<start_read>.	1570	C<start_read>.
		1571
		1572	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1573	you change the C<on_read> callback or push/unshift a read callback, and it
		1574	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1575	there are any read requests in the queue.
		1576
		1577	These methods will have no effect when in TLS mode (as TLS doesn't support
		1578	half-duplex connections).
563		1579
564	=cut	1580	=cut
565		1581
566	sub stop_read {	1582	sub stop_read {
567	my ($self) = @_;	1583	my ($self) = @_;
568		1584
569	delete $self->{rw};	1585	delete $self->{_rw} unless $self->{tls};
570	}	1586	}
571		1587
572	sub start_read {	1588	sub start_read {
573	my ($self) = @_;	1589	my ($self) = @_;
574		1590
575	unless ($self->{rw} || $self->{eof}) {	1591	unless ($self->{_rw} || $self->{_eof}) {
576	Scalar::Util::weaken $self;	1592	Scalar::Util::weaken $self;
577		1593
578	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1594	$self->{_rw} = AE::io $self->{fh}, 0, sub {
		1595	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
579	my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} || 8192, length $self->{rbuf};	1596	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
580		1597
581	if ($len > 0) {	1598	if ($len > 0) {
582	if (defined $self->{rbuf_max}) {	1599	$self->{_activity} = $self->{_ractivity} = AE::now;
583	if ($self->{rbuf_max} < length $self->{rbuf}) {	1600
584	$! = &Errno::ENOSPC; return $self->error;	1601	if ($self->{tls}) {
585	}	1602	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1603
		1604	&_dotls ($self);
		1605	} else {
		1606	$self->_drain_rbuf;
586	}	1607	}
587		1608
588	} elsif (defined $len) {	1609	} elsif (defined $len) {
589	$self->{eof} = 1;
590	delete $self->{rw};	1610	delete $self->{_rw};
		1611	$self->{_eof} = 1;
		1612	$self->_drain_rbuf;
591		1613
592	} elsif ($! != EAGAIN && $! != EINTR) {	1614	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
593	return $self->error;	1615	return $self->_error ($!, 1);
594	}	1616	}
		1617	};
		1618	}
		1619	}
595		1620
		1621	our $ERROR_SYSCALL;
		1622	our $ERROR_WANT_READ;
		1623
		1624	sub _tls_error {
		1625	my ($self, $err) = @_;
		1626
		1627	return $self->_error ($!, 1)
		1628	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1629
		1630	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1631
		1632	# reduce error string to look less scary
		1633	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1634
		1635	if ($self->{_on_starttls}) {
		1636	(delete $self->{_on_starttls})->($self, undef, $err);
		1637	&_freetls;
		1638	} else {
		1639	&_freetls;
		1640	$self->_error (Errno::EPROTO, 1, $err);
		1641	}
		1642	}
		1643
		1644	# poll the write BIO and send the data if applicable
		1645	# also decode read data if possible
		1646	# this is basiclaly our TLS state machine
		1647	# more efficient implementations are possible with openssl,
		1648	# but not with the buggy and incomplete Net::SSLeay.
		1649	sub _dotls {
		1650	my ($self) = @_;
		1651
		1652	my $tmp;
		1653
		1654	if (length $self->{_tls_wbuf}) {
		1655	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		1656	substr $self->{_tls_wbuf}, 0, $tmp, "";
		1657	}
		1658
		1659	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1660	return $self->_tls_error ($tmp)
		1661	if $tmp != $ERROR_WANT_READ
		1662	&& ($tmp != $ERROR_SYSCALL || $!);
		1663	}
		1664
		1665	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1666	unless (length $tmp) {
		1667	$self->{_on_starttls}
		1668	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1669	&_freetls;
		1670
		1671	if ($self->{on_stoptls}) {
		1672	$self->{on_stoptls}($self);
		1673	return;
		1674	} else {
		1675	# let's treat SSL-eof as we treat normal EOF
		1676	delete $self->{_rw};
		1677	$self->{_eof} = 1;
		1678	}
		1679	}
		1680
		1681	$self->{_tls_rbuf} .= $tmp;
596	$self->_drain_rbuf;	1682	$self->_drain_rbuf;
		1683	$self->{tls} or return; # tls session might have gone away in callback
		1684	}
		1685
		1686	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1687	return $self->_tls_error ($tmp)
		1688	if $tmp != $ERROR_WANT_READ
		1689	&& ($tmp != $ERROR_SYSCALL || $!);
		1690
		1691	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1692	$self->{wbuf} .= $tmp;
		1693	$self->_drain_wbuf;
		1694	}
		1695
		1696	$self->{_on_starttls}
		1697	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
		1698	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
		1699	}
		1700
		1701	=item $handle->starttls ($tls[, $tls_ctx])
		1702
		1703	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1704	object is created, you can also do that at a later time by calling
		1705	C<starttls>.
		1706
		1707	Starting TLS is currently an asynchronous operation - when you push some
		1708	write data and then call C<< ->starttls >> then TLS negotiation will start
		1709	immediately, after which the queued write data is then sent.
		1710
		1711	The first argument is the same as the C<tls> constructor argument (either
		1712	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1713
		1714	The second argument is the optional C<AnyEvent::TLS> object that is used
		1715	when AnyEvent::Handle has to create its own TLS connection object, or
		1716	a hash reference with C<< key => value >> pairs that will be used to
		1717	construct a new context.
		1718
		1719	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
		1720	context in C<< $handle->{tls_ctx} >> after this call and can be used or
		1721	changed to your liking. Note that the handshake might have already started
		1722	when this function returns.
		1723
		1724	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1725	handshakes on the same stream. Best do not attempt to use the stream after
		1726	stopping TLS.
		1727
		1728	=cut
		1729
		1730	our %TLS_CACHE; #TODO not yet documented, should we?
		1731
		1732	sub starttls {
		1733	my ($self, $tls, $ctx) = @_;
		1734
		1735	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1736	if $self->{tls};
		1737
		1738	$self->{tls} = $tls;
		1739	$self->{tls_ctx} = $ctx if @_ > 2;
		1740
		1741	return unless $self->{fh};
		1742
		1743	require Net::SSLeay;
		1744
		1745	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		1746	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1747
		1748	$tls = $self->{tls};
		1749	$ctx = $self->{tls_ctx};
		1750
		1751	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1752
		1753	if ("HASH" eq ref $ctx) {
		1754	require AnyEvent::TLS;
		1755
		1756	if ($ctx->{cache}) {
		1757	my $key = $ctx+0;
		1758	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1759	} else {
		1760	$ctx = new AnyEvent::TLS %$ctx;
		1761	}
		1762	}
		1763
		1764	$self->{tls_ctx} = $ctx || TLS_CTX ();
		1765	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
		1766
		1767	# basically, this is deep magic (because SSL_read should have the same issues)
		1768	# but the openssl maintainers basically said: "trust us, it just works".
		1769	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1770	# and mismaintained ssleay-module doesn't even offer them).
		1771	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1772	#
		1773	# in short: this is a mess.
		1774	#
		1775	# note that we do not try to keep the length constant between writes as we are required to do.
		1776	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1777	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1778	# have identity issues in that area.
		1779	# Net::SSLeay::CTX_set_mode ($ssl,
		1780	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1781	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1782	Net::SSLeay::CTX_set_mode ($tls, 1|2);
		1783
		1784	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1785	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1786
		1787	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		1788
		1789	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
		1790
		1791	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
		1792	if $self->{on_starttls};
		1793
		1794	&_dotls; # need to trigger the initial handshake
		1795	$self->start_read; # make sure we actually do read
		1796	}
		1797
		1798	=item $handle->stoptls
		1799
		1800	Shuts down the SSL connection - this makes a proper EOF handshake by
		1801	sending a close notify to the other side, but since OpenSSL doesn't
		1802	support non-blocking shut downs, it is not guarenteed that you can re-use
		1803	the stream afterwards.
		1804
		1805	=cut
		1806
		1807	sub stoptls {
		1808	my ($self) = @_;
		1809
		1810	if ($self->{tls}) {
		1811	Net::SSLeay::shutdown ($self->{tls});
		1812
		1813	&_dotls;
		1814
		1815	# # we don't give a shit. no, we do, but we can't. no...#d#
		1816	# # we, we... have to use openssl :/#d#
		1817	# &_freetls;#d#
		1818	}
		1819	}
		1820
		1821	sub _freetls {
		1822	my ($self) = @_;
		1823
		1824	return unless $self->{tls};
		1825
		1826	$self->{tls_ctx}->_put_session (delete $self->{tls})
		1827	if $self->{tls} > 0;
		1828
		1829	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		1830	}
		1831
		1832	sub DESTROY {
		1833	my ($self) = @_;
		1834
		1835	&_freetls;
		1836
		1837	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1838
		1839	if ($linger && length $self->{wbuf} && $self->{fh}) {
		1840	my $fh = delete $self->{fh};
		1841	my $wbuf = delete $self->{wbuf};
		1842
		1843	my @linger;
		1844
		1845	push @linger, AE::io $fh, 1, sub {
		1846	my $len = syswrite $fh, $wbuf, length $wbuf;
		1847
		1848	if ($len > 0) {
		1849	substr $wbuf, 0, $len, "";
		1850	} else {
		1851	@linger = (); # end
		1852	}
597	});	1853	};
		1854	push @linger, AE::timer $linger, 0, sub {
		1855	@linger = ();
		1856	};
		1857	}
		1858	}
		1859
		1860	=item $handle->destroy
		1861
		1862	Shuts down the handle object as much as possible - this call ensures that
		1863	no further callbacks will be invoked and as many resources as possible
		1864	will be freed. Any method you will call on the handle object after
		1865	destroying it in this way will be silently ignored (and it will return the
		1866	empty list).
		1867
		1868	Normally, you can just "forget" any references to an AnyEvent::Handle
		1869	object and it will simply shut down. This works in fatal error and EOF
		1870	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1871	callback, so when you want to destroy the AnyEvent::Handle object from
		1872	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1873	that case.
		1874
		1875	Destroying the handle object in this way has the advantage that callbacks
		1876	will be removed as well, so if those are the only reference holders (as
		1877	is common), then one doesn't need to do anything special to break any
		1878	reference cycles.
		1879
		1880	The handle might still linger in the background and write out remaining
		1881	data, as specified by the C<linger> option, however.
		1882
		1883	=cut
		1884
		1885	sub destroy {
		1886	my ($self) = @_;
		1887
		1888	$self->DESTROY;
		1889	%$self = ();
		1890	bless $self, "AnyEvent::Handle::destroyed";
		1891	}
		1892
		1893	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		1894	#nop
		1895	}
		1896
		1897	=item AnyEvent::Handle::TLS_CTX
		1898
		1899	This function creates and returns the AnyEvent::TLS object used by default
		1900	for TLS mode.
		1901
		1902	The context is created by calling L<AnyEvent::TLS> without any arguments.
		1903
		1904	=cut
		1905
		1906	our $TLS_CTX;
		1907
		1908	sub TLS_CTX() {
		1909	$TLS_CTX ||= do {
		1910	require AnyEvent::TLS;
		1911
		1912	new AnyEvent::TLS
598	}	1913	}
599	}	1914	}
600		1915
601	=back	1916	=back
602		1917
		1918
		1919	=head1 NONFREQUENTLY ASKED QUESTIONS
		1920
		1921	=over 4
		1922
		1923	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1924	still get further invocations!
		1925
		1926	That's because AnyEvent::Handle keeps a reference to itself when handling
		1927	read or write callbacks.
		1928
		1929	It is only safe to "forget" the reference inside EOF or error callbacks,
		1930	from within all other callbacks, you need to explicitly call the C<<
		1931	->destroy >> method.
		1932
		1933	=item I get different callback invocations in TLS mode/Why can't I pause
		1934	reading?
		1935
		1936	Unlike, say, TCP, TLS connections do not consist of two independent
		1937	communication channels, one for each direction. Or put differently. The
		1938	read and write directions are not independent of each other: you cannot
		1939	write data unless you are also prepared to read, and vice versa.
		1940
		1941	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1942	callback invocations when you are not expecting any read data - the reason
		1943	is that AnyEvent::Handle always reads in TLS mode.
		1944
		1945	During the connection, you have to make sure that you always have a
		1946	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1947	connection (or when you no longer want to use it) you can call the
		1948	C<destroy> method.
		1949
		1950	=item How do I read data until the other side closes the connection?
		1951
		1952	If you just want to read your data into a perl scalar, the easiest way
		1953	to achieve this is by setting an C<on_read> callback that does nothing,
		1954	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1955	will be in C<$_[0]{rbuf}>:
		1956
		1957	$handle->on_read (sub { });
		1958	$handle->on_eof (undef);
		1959	$handle->on_error (sub {
		1960	my $data = delete $_[0]{rbuf};
		1961	});
		1962
		1963	The reason to use C<on_error> is that TCP connections, due to latencies
		1964	and packets loss, might get closed quite violently with an error, when in
		1965	fact, all data has been received.
		1966
		1967	It is usually better to use acknowledgements when transferring data,
		1968	to make sure the other side hasn't just died and you got the data
		1969	intact. This is also one reason why so many internet protocols have an
		1970	explicit QUIT command.
		1971
		1972	=item I don't want to destroy the handle too early - how do I wait until
		1973	all data has been written?
		1974
		1975	After writing your last bits of data, set the C<on_drain> callback
		1976	and destroy the handle in there - with the default setting of
		1977	C<low_water_mark> this will be called precisely when all data has been
		1978	written to the socket:
		1979
		1980	$handle->push_write (...);
		1981	$handle->on_drain (sub {
		1982	warn "all data submitted to the kernel\n";
		1983	undef $handle;
		1984	});
		1985
		1986	If you just want to queue some data and then signal EOF to the other side,
		1987	consider using C<< ->push_shutdown >> instead.
		1988
		1989	=item I want to contact a TLS/SSL server, I don't care about security.
		1990
		1991	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		1992	simply connect to it and then create the AnyEvent::Handle with the C<tls>
		1993	parameter:
		1994
		1995	tcp_connect $host, $port, sub {
		1996	my ($fh) = @_;
		1997
		1998	my $handle = new AnyEvent::Handle
		1999	fh => $fh,
		2000	tls => "connect",
		2001	on_error => sub { ... };
		2002
		2003	$handle->push_write (...);
		2004	};
		2005
		2006	=item I want to contact a TLS/SSL server, I do care about security.
		2007
		2008	Then you should additionally enable certificate verification, including
		2009	peername verification, if the protocol you use supports it (see
		2010	L<AnyEvent::TLS>, C<verify_peername>).
		2011
		2012	E.g. for HTTPS:
		2013
		2014	tcp_connect $host, $port, sub {
		2015	my ($fh) = @_;
		2016
		2017	my $handle = new AnyEvent::Handle
		2018	fh => $fh,
		2019	peername => $host,
		2020	tls => "connect",
		2021	tls_ctx => { verify => 1, verify_peername => "https" },
		2022	...
		2023
		2024	Note that you must specify the hostname you connected to (or whatever
		2025	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2026	peername verification will be done.
		2027
		2028	The above will use the system-dependent default set of trusted CA
		2029	certificates. If you want to check against a specific CA, add the
		2030	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2031
		2032	tls_ctx => {
		2033	verify => 1,
		2034	verify_peername => "https",
		2035	ca_file => "my-ca-cert.pem",
		2036	},
		2037
		2038	=item I want to create a TLS/SSL server, how do I do that?
		2039
		2040	Well, you first need to get a server certificate and key. You have
		2041	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2042	self-signed certificate (cheap. check the search engine of your choice,
		2043	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2044	nice program for that purpose).
		2045
		2046	Then create a file with your private key (in PEM format, see
		2047	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2048	file should then look like this:
		2049
		2050	-----BEGIN RSA PRIVATE KEY-----
		2051	...header data
		2052	... lots of base64'y-stuff
		2053	-----END RSA PRIVATE KEY-----
		2054
		2055	-----BEGIN CERTIFICATE-----
		2056	... lots of base64'y-stuff
		2057	-----END CERTIFICATE-----
		2058
		2059	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2060	specify this file as C<cert_file>:
		2061
		2062	tcp_server undef, $port, sub {
		2063	my ($fh) = @_;
		2064
		2065	my $handle = new AnyEvent::Handle
		2066	fh => $fh,
		2067	tls => "accept",
		2068	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2069	...
		2070
		2071	When you have intermediate CA certificates that your clients might not
		2072	know about, just append them to the C<cert_file>.
		2073
		2074	=back
		2075
		2076
		2077	=head1 SUBCLASSING AnyEvent::Handle
		2078
		2079	In many cases, you might want to subclass AnyEvent::Handle.
		2080
		2081	To make this easier, a given version of AnyEvent::Handle uses these
		2082	conventions:
		2083
		2084	=over 4
		2085
		2086	=item * all constructor arguments become object members.
		2087
		2088	At least initially, when you pass a C<tls>-argument to the constructor it
		2089	will end up in C<< $handle->{tls} >>. Those members might be changed or
		2090	mutated later on (for example C<tls> will hold the TLS connection object).
		2091
		2092	=item * other object member names are prefixed with an C<_>.
		2093
		2094	All object members not explicitly documented (internal use) are prefixed
		2095	with an underscore character, so the remaining non-C<_>-namespace is free
		2096	for use for subclasses.
		2097
		2098	=item * all members not documented here and not prefixed with an underscore
		2099	are free to use in subclasses.
		2100
		2101	Of course, new versions of AnyEvent::Handle may introduce more "public"
		2102	member variables, but thats just life, at least it is documented.
		2103
		2104	=back
		2105
603	=head1 AUTHOR	2106	=head1 AUTHOR
604		2107
605	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	2108	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
606		2109
607	=cut	2110	=cut

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