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Revision 1.4 by elmex, Sun Apr 27 20:20:20 2008 UTC vs.
Revision 1.206 by root, Mon Nov 15 19:49:31 2010 UTC

1	package AnyEvent::Handle;
2
3	use warnings;
4	use strict;
5
6	use AnyEvent;
7	use IO::Handle;
8	use Errno qw/EAGAIN EINTR/;
9
10	=head1 NAME	1	=head1 NAME
11		2
12	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
13
14	=head1 VERSION
15
16	Version 0.01
17
18	=cut
19
20	our $VERSION = '0.01';
21		4
22	=head1 SYNOPSIS	5	=head1 SYNOPSIS
23		6
24	use AnyEvent;	7	use AnyEvent;
25	use AnyEvent::Handle;	8	use AnyEvent::Handle;
26		9
27	my $cv = AnyEvent->condvar;	10	my $cv = AnyEvent->condvar;
28		11
29	my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	12	my $hdl; $hdl = new AnyEvent::Handle
		13	fh => \*STDIN,
		14	on_error => sub {
		15	my ($hdl, $fatal, $msg) = @_;
		16	warn "got error $msg\n";
		17	$hdl->destroy;
		18	$cv->send;
		19	};
30		20
31	$ae_fh->on_eof (sub { $cv->broadcast });	21	# send some request line
		22	$hdl->push_write ("getinfo\015\012");
32		23
33	$ae_fh->readlines (sub {	24	# read the response line
		25	$hdl->push_read (line => sub {
34	my ($ae_fh, @lines) = @_;	26	my ($hdl, $line) = @_;
35	for (@lines) {	27	warn "got line <$line>\n";
		28	$cv->send;
		29	});
		30
		31	$cv->recv;
		32
		33	=head1 DESCRIPTION
		34
		35	This is a helper module to make it easier to do event-based I/O on
		36	stream-based filehandles (sockets, pipes, and other stream things).
		37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
		40
		41	In the following, where the documentation refers to "bytes", it means
		42	characters. As sysread and syswrite are used for all I/O, their
		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.
		47
		48	All callbacks will be invoked with the handle object as their first
		49	argument.
		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
		82	=head1 METHODS
		83
		84	=over 4
		85
		86	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
		87
		88	The constructor supports these arguments (all as C<< key => value >> pairs).
		89
		90	=over 4
		91
		92	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
		93
		94	The filehandle this L<AnyEvent::Handle> object will operate on.
		95	NOTE: The filehandle will be set to non-blocking mode (using
		96	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		97	that mode.
		98
		99	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
		100
		101	Try to connect to the specified host and service (port), using
		102	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		103	default C<peername>.
		104
		105	You have to specify either this parameter, or C<fh>, above.
		106
		107	It is possible to push requests on the read and write queues, and modify
		108	properties of the stream, even while AnyEvent::Handle is connecting.
		109
		110	When this parameter is specified, then the C<on_prepare>,
		111	C<on_connect_error> and C<on_connect> callbacks will be called under the
		112	appropriate circumstances:
		113
		114	=over 4
		115
		116	=item on_prepare => $cb->($handle)
		117
		118	This (rarely used) callback is called before a new connection is
		119	attempted, but after the file handle has been created. It could be used to
		120	prepare the file handle with parameters required for the actual connect
		121	(as opposed to settings that can be changed when the connection is already
		122	established).
		123
		124	The return value of this callback should be the connect timeout value in
		125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
		126	default timeout is to be used).
		127
		128	=item on_connect => $cb->($handle, $host, $port, $retry->())
		129
		130	This callback is called when a connection has been successfully established.
		131
		132	The peer's numeric host and port (the socket peername) are passed as
		133	parameters, together with a retry callback.
		134
		135	If, for some reason, the handle is not acceptable, calling C<$retry>
		136	will continue with the next connection target (in case of multi-homed
		137	hosts or SRV records there can be multiple connection endpoints). At the
		138	time it is called the read and write queues, eof status, tls status and
		139	similar properties of the handle will have been reset.
		140
		141	In most cases, you should ignore the C<$retry> parameter.
		142
		143	=item on_connect_error => $cb->($handle, $message)
		144
		145	This callback is called when the connection could not be
		146	established. C<$!> will contain the relevant error code, and C<$message> a
		147	message describing it (usually the same as C<"$!">).
		148
		149	If this callback isn't specified, then C<on_error> will be called with a
		150	fatal error instead.
		151
		152	=back
		153
		154	=item on_error => $cb->($handle, $fatal, $message)
		155
		156	This is the error callback, which is called when, well, some error
		157	occured, such as not being able to resolve the hostname, failure to
		158	connect, or a read error.
		159
		160	Some errors are fatal (which is indicated by C<$fatal> being true). On
		161	fatal errors the handle object will be destroyed (by a call to C<< ->
		162	destroy >>) after invoking the error callback (which means you are free to
		163	examine the handle object). Examples of fatal errors are an EOF condition
		164	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
		165	cases where the other side can close the connection at will, it is
		166	often easiest to not report C<EPIPE> errors in this callback.
		167
		168	AnyEvent::Handle tries to find an appropriate error code for you to check
		169	against, but in some cases (TLS errors), this does not work well. It is
		170	recommended to always output the C<$message> argument in human-readable
		171	error messages (it's usually the same as C<"$!">).
		172
		173	Non-fatal errors can be retried by returning, but it is recommended
		174	to simply ignore this parameter and instead abondon the handle object
		175	when this callback is invoked. Examples of non-fatal errors are timeouts
		176	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		177
		178	On entry to the callback, the value of C<$!> contains the operating
		179	system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		180	C<EPROTO>).
		181
		182	While not mandatory, it is I<highly> recommended to set this callback, as
		183	you will not be notified of errors otherwise. The default just calls
		184	C<croak>.
		185
		186	=item on_read => $cb->($handle)
		187
		188	This sets the default read callback, which is called when data arrives
		189	and no read request is in the queue (unlike read queue callbacks, this
		190	callback will only be called when at least one octet of data is in the
		191	read buffer).
		192
		193	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		194	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		195	must not enlarge or modify the read buffer, you can only remove data at
		196	the beginning from it.
		197
		198	You can also call C<< ->push_read (...) >> or any other function that
		199	modifies the read queue. Or do both. Or ...
		200
		201	When an EOF condition is detected, AnyEvent::Handle will first try to
		202	feed all the remaining data to the queued callbacks and C<on_read> before
		203	calling the C<on_eof> callback. If no progress can be made, then a fatal
		204	error will be raised (with C<$!> set to C<EPIPE>).
		205
		206	Note that, unlike requests in the read queue, an C<on_read> callback
		207	doesn't mean you I<require> some data: if there is an EOF and there
		208	are outstanding read requests then an error will be flagged. With an
		209	C<on_read> callback, the C<on_eof> callback will be invoked.
		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
		227	=item on_drain => $cb->($handle)
		228
		229	This sets the callback that is called when the write buffer becomes empty
		230	(or immediately if the buffer is empty already).
		231
		232	To append to the write buffer, use the C<< ->push_write >> method.
		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
		240	=item timeout => $fractional_seconds
		241
		242	=item rtimeout => $fractional_seconds
		243
		244	=item wtimeout => $fractional_seconds
		245
		246	If non-zero, then these enables an "inactivity" timeout: whenever this
		247	many seconds pass without a successful read or write on the underlying
		248	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
		249	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		250	error will be raised).
		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
		258	Note that timeout processing is active even when you do not have
		259	any outstanding read or write requests: If you plan to keep the connection
		260	idle then you should disable the timeout temporarily or ignore the timeout
		261	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		262	restart the timeout.
		263
		264	Zero (the default) disables this timeout.
		265
		266	=item on_timeout => $cb->($handle)
		267
		268	Called whenever the inactivity timeout passes. If you return from this
		269	callback, then the timeout will be reset as if some activity had happened,
		270	so this condition is not fatal in any way.
		271
		272	=item rbuf_max => <bytes>
		273
		274	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		275	when the read buffer ever (strictly) exceeds this size. This is useful to
		276	avoid some forms of denial-of-service attacks.
		277
		278	For example, a server accepting connections from untrusted sources should
		279	be configured to accept only so-and-so much data that it cannot act on
		280	(for example, when expecting a line, an attacker could send an unlimited
		281	amount of data without a callback ever being called as long as the line
		282	isn't finished).
		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
		342	=item read_size => <bytes>
		343
		344	The initial read block size, the number of bytes this module will try to
		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.
		355
		356	=item low_water_mark => <bytes>
		357
		358	Sets the number of bytes (default: C<0>) that make up an "empty" write
		359	buffer: If the buffer reaches this size or gets even samller it is
		360	considered empty.
		361
		362	Sometimes it can be beneficial (for performance reasons) to add data to
		363	the write buffer before it is fully drained, but this is a rare case, as
		364	the operating system kernel usually buffers data as well, so the default
		365	is good in almost all cases.
		366
		367	=item linger => <seconds>
		368
		369	If this is non-zero (default: C<3600>), the destructor of the
		370	AnyEvent::Handle object will check whether there is still outstanding
		371	write data and will install a watcher that will write this data to the
		372	socket. No errors will be reported (this mostly matches how the operating
		373	system treats outstanding data at socket close time).
		374
		375	This will not work for partial TLS data that could not be encoded
		376	yet. This data will be lost. Calling the C<stoptls> method in time might
		377	help.
		378
		379	=item peername => $string
		380
		381	A string used to identify the remote site - usually the DNS hostname
		382	(I<not> IDN!) used to create the connection, rarely the IP address.
		383
		384	Apart from being useful in error messages, this string is also used in TLS
		385	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		386	verification will be skipped when C<peername> is not specified or is
		387	C<undef>.
		388
		389	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
		390
		391	When this parameter is given, it enables TLS (SSL) mode, that means
		392	AnyEvent will start a TLS handshake as soon as the connection has been
		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.
		397
		398	TLS mode requires Net::SSLeay to be installed (it will be loaded
		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.
		402
		403	Unlike TCP, TLS has a server and client side: for the TLS server side, use
		404	C<accept>, and for the TLS client side of a connection, use C<connect>
		405	mode.
		406
		407	You can also provide your own TLS connection object, but you have
		408	to make sure that you call either C<Net::SSLeay::set_connect_state>
		409	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		410	AnyEvent::Handle. Also, this module will take ownership of this connection
		411	object.
		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
		422	Use the C<< ->starttls >> method if you need to start TLS negotiation later.
		423
		424	=item tls_ctx => $anyevent_tls
		425
		426	Use the given C<AnyEvent::TLS> object to create the new TLS connection
		427	(unless a connection object was specified directly). If this parameter is
		428	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		429
		430	Instead of an object, you can also specify a hash reference with C<< key
		431	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		432	new TLS context object.
		433
		434	=item on_starttls => $cb->($handle, $success[, $error_message])
		435
		436	This callback will be invoked when the TLS/SSL handshake has finished. If
		437	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		438	(C<on_stoptls> will not be called in this case).
		439
		440	The session in C<< $handle->{tls} >> can still be examined in this
		441	callback, even when the handshake was not successful.
		442
		443	TLS handshake failures will not cause C<on_error> to be invoked when this
		444	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		445
		446	Without this callback, handshake failures lead to C<on_error> being
		447	called as usual.
		448
		449	Note that you cannot just call C<starttls> again in this callback. If you
		450	need to do that, start an zero-second timer instead whose callback can
		451	then call C<< ->starttls >> again.
		452
		453	=item on_stoptls => $cb->($handle)
		454
		455	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		456	set, then it will be invoked after freeing the TLS session. If it is not,
		457	then a TLS shutdown condition will be treated like a normal EOF condition
		458	on the handle.
		459
		460	The session in C<< $handle->{tls} >> can still be examined in this
		461	callback.
		462
		463	This callback will only be called on TLS shutdowns, not when the
		464	underlying handle signals EOF.
		465
		466	=item json => JSON or JSON::XS object
		467
		468	This is the json coder object used by the C<json> read and write types.
		469
		470	If you don't supply it, then AnyEvent::Handle will create and use a
		471	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		472	texts.
		473
		474	Note that you are responsible to depend on the JSON module if you want to
		475	use this functionality, as AnyEvent does not have a dependency itself.
		476
		477	=back
		478
		479	=cut
		480
		481	sub new {
		482	my $class = shift;
		483	my $self = bless { @_ }, $class;
		484
		485	if ($self->{fh}) {
		486	$self->_start;
		487	return unless $self->{fh}; # could be gone by now
		488
		489	} elsif ($self->{connect}) {
		490	require AnyEvent::Socket;
		491
		492	$self->{peername} = $self->{connect}[0]
		493	unless exists $self->{peername};
		494
		495	$self->{_skip_drain_rbuf} = 1;
		496
		497	{
		498	Scalar::Util::weaken (my $self = $self);
		499
		500	$self->{_connect} =
		501	AnyEvent::Socket::tcp_connect (
		502	$self->{connect}[0],
		503	$self->{connect}[1],
		504	sub {
		505	my ($fh, $host, $port, $retry) = @_;
		506
		507	delete $self->{_connect}; # no longer needed
		508
		509	if ($fh) {
		510	$self->{fh} = $fh;
		511
		512	delete $self->{_skip_drain_rbuf};
		513	$self->_start;
		514
		515	$self->{on_connect}
		516	and $self->{on_connect}($self, $host, $port, sub {
		517	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		518	$self->{_skip_drain_rbuf} = 1;
		519	&$retry;
		520	});
		521
		522	} else {
		523	if ($self->{on_connect_error}) {
		524	$self->{on_connect_error}($self, "$!");
		525	$self->destroy;
		526	} else {
		527	$self->_error ($!, 1);
		528	}
		529	}
		530	},
		531	sub {
		532	local $self->{fh} = $_[0];
		533
		534	$self->{on_prepare}
		535	? $self->{on_prepare}->($self)
		536	: ()
		537	}
		538	);
		539	}
		540
		541	} else {
		542	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		543	}
		544
		545	$self
		546	}
		547
		548	sub _start {
		549	my ($self) = @_;
		550
		551	# too many clueless people try to use udp and similar sockets
		552	# with AnyEvent::Handle, do them a favour.
		553	my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
		554	Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
		555	if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
		556
		557	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
		558
		559	$self->{_activity} =
		560	$self->{_ractivity} =
		561	$self->{_wactivity} = AE::now;
		562
		563	$self->{read_size} ||= 2048;
		564	$self->{max_read_size} = $self->{read_size}
		565	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		566
		567	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		568	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		569	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		570
		571	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		572	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		573
		574	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		575
		576	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
		577	if $self->{tls};
		578
		579	$self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
		580
		581	$self->start_read
		582	if $self->{on_read} || @{ $self->{_queue} };
		583
		584	$self->_drain_wbuf;
		585	}
		586
		587	sub _error {
		588	my ($self, $errno, $fatal, $message) = @_;
		589
		590	$! = $errno;
		591	$message ||= "$!";
		592
		593	if ($self->{on_error}) {
		594	$self->{on_error}($self, $fatal, $message);
		595	$self->destroy if $fatal;
		596	} elsif ($self->{fh} || $self->{connect}) {
		597	$self->destroy;
		598	Carp::croak "AnyEvent::Handle uncaught error: $message";
		599	}
		600	}
		601
		602	=item $fh = $handle->fh
		603
		604	This method returns the file handle used to create the L<AnyEvent::Handle> object.
		605
		606	=cut
		607
		608	sub fh { $_[0]{fh} }
		609
		610	=item $handle->on_error ($cb)
		611
		612	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
		613
		614	=cut
		615
		616	sub on_error {
		617	$_[0]{on_error} = $_[1];
		618	}
		619
		620	=item $handle->on_eof ($cb)
		621
		622	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
		623
		624	=cut
		625
		626	sub on_eof {
		627	$_[0]{on_eof} = $_[1];
		628	}
		629
		630	=item $handle->on_timeout ($cb)
		631
		632	=item $handle->on_rtimeout ($cb)
		633
		634	=item $handle->on_wtimeout ($cb)
		635
		636	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		637	callback, or disables the callback (but not the timeout) if C<$cb> =
		638	C<undef>. See the C<timeout> constructor argument and method.
		639
		640	=cut
		641
		642	# see below
		643
		644	=item $handle->autocork ($boolean)
		645
		646	Enables or disables the current autocork behaviour (see C<autocork>
		647	constructor argument). Changes will only take effect on the next write.
		648
		649	=cut
		650
		651	sub autocork {
		652	$_[0]{autocork} = $_[1];
		653	}
		654
		655	=item $handle->no_delay ($boolean)
		656
		657	Enables or disables the C<no_delay> setting (see constructor argument of
		658	the same name for details).
		659
		660	=cut
		661
		662	sub no_delay {
		663	$_[0]{no_delay} = $_[1];
		664
		665	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		666	if $_[0]{fh};
		667	}
		668
		669	=item $handle->keepalive ($boolean)
		670
		671	Enables or disables the C<keepalive> setting (see constructor argument of
		672	the same name for details).
		673
		674	=cut
		675
		676	sub keepalive {
		677	$_[0]{keepalive} = $_[1];
		678
		679	eval {
		680	local $SIG{__DIE__};
		681	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		682	if $_[0]{fh};
		683	};
		684	}
		685
		686	=item $handle->oobinline ($boolean)
		687
		688	Enables or disables the C<oobinline> setting (see constructor argument of
		689	the same name for details).
		690
		691	=cut
		692
		693	sub oobinline {
		694	$_[0]{oobinline} = $_[1];
		695
		696	eval {
		697	local $SIG{__DIE__};
		698	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		699	if $_[0]{fh};
		700	};
		701	}
		702
		703	=item $handle->keepalive ($boolean)
		704
		705	Enables or disables the C<keepalive> setting (see constructor argument of
		706	the same name for details).
		707
		708	=cut
		709
		710	sub keepalive {
		711	$_[0]{keepalive} = $_[1];
		712
		713	eval {
		714	local $SIG{__DIE__};
		715	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		716	if $_[0]{fh};
		717	};
		718	}
		719
		720	=item $handle->on_starttls ($cb)
		721
		722	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		723
		724	=cut
		725
		726	sub on_starttls {
		727	$_[0]{on_starttls} = $_[1];
		728	}
		729
		730	=item $handle->on_stoptls ($cb)
		731
		732	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		733
		734	=cut
		735
		736	sub on_stoptls {
		737	$_[0]{on_stoptls} = $_[1];
		738	}
		739
		740	=item $handle->rbuf_max ($max_octets)
		741
		742	Configures the C<rbuf_max> setting (C<undef> disables it).
		743
		744	=cut
		745
		746	sub rbuf_max {
		747	$_[0]{rbuf_max} = $_[1];
		748	}
		749
		750	#############################################################################
		751
		752	=item $handle->timeout ($seconds)
		753
		754	=item $handle->rtimeout ($seconds)
		755
		756	=item $handle->wtimeout ($seconds)
		757
		758	Configures (or disables) the inactivity timeout.
		759
		760	=item $handle->timeout_reset
		761
		762	=item $handle->rtimeout_reset
		763
		764	=item $handle->wtimeout_reset
		765
		766	Reset the activity timeout, as if data was received or sent.
		767
		768	These methods are cheap to call.
		769
		770	=cut
		771
		772	for my $dir ("", "r", "w") {
		773	my $timeout = "${dir}timeout";
		774	my $tw = "_${dir}tw";
		775	my $on_timeout = "on_${dir}timeout";
		776	my $activity = "_${dir}activity";
		777	my $cb;
		778
		779	*$on_timeout = sub {
		780	$_[0]{$on_timeout} = $_[1];
		781	};
		782
		783	*$timeout = sub {
		784	my ($self, $new_value) = @_;
		785
		786	$new_value >= 0
		787	or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
		788
		789	$self->{$timeout} = $new_value;
		790	delete $self->{$tw}; &$cb;
		791	};
		792
		793	*{"${dir}timeout_reset"} = sub {
		794	$_[0]{$activity} = AE::now;
		795	};
		796
		797	# main workhorse:
		798	# reset the timeout watcher, as neccessary
		799	# also check for time-outs
		800	$cb = sub {
		801	my ($self) = @_;
		802
		803	if ($self->{$timeout} && $self->{fh}) {
		804	my $NOW = AE::now;
		805
		806	# when would the timeout trigger?
		807	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		808
		809	# now or in the past already?
		810	if ($after <= 0) {
		811	$self->{$activity} = $NOW;
		812
		813	if ($self->{$on_timeout}) {
		814	$self->{$on_timeout}($self);
		815	} else {
		816	$self->_error (Errno::ETIMEDOUT);
		817	}
		818
		819	# callback could have changed timeout value, optimise
		820	return unless $self->{$timeout};
		821
		822	# calculate new after
		823	$after = $self->{$timeout};
		824	}
		825
		826	Scalar::Util::weaken $self;
		827	return unless $self; # ->error could have destroyed $self
		828
		829	$self->{$tw} ||= AE::timer $after, 0, sub {
		830	delete $self->{$tw};
		831	$cb->($self);
36	chomp;	832	};
37	print "Line: $_";	833	} else {
		834	delete $self->{$tw};
		835	}
		836	}
		837	}
		838
		839	#############################################################################
		840
		841	=back
		842
		843	=head2 WRITE QUEUE
		844
		845	AnyEvent::Handle manages two queues per handle, one for writing and one
		846	for reading.
		847
		848	The write queue is very simple: you can add data to its end, and
		849	AnyEvent::Handle will automatically try to get rid of it for you.
		850
		851	When data could be written and the write buffer is shorter then the low
		852	water mark, the C<on_drain> callback will be invoked.
		853
		854	=over 4
		855
		856	=item $handle->on_drain ($cb)
		857
		858	Sets the C<on_drain> callback or clears it (see the description of
		859	C<on_drain> in the constructor).
		860
		861	This method may invoke callbacks (and therefore the handle might be
		862	destroyed after it returns).
		863
		864	=cut
		865
		866	sub on_drain {
		867	my ($self, $cb) = @_;
		868
		869	$self->{on_drain} = $cb;
		870
		871	$cb->($self)
		872	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
		873	}
		874
		875	=item $handle->push_write ($data)
		876
		877	Queues the given scalar to be written. You can push as much data as you
		878	want (only limited by the available memory), as C<AnyEvent::Handle>
		879	buffers it independently of the kernel.
		880
		881	This method may invoke callbacks (and therefore the handle might be
		882	destroyed after it returns).
		883
		884	=cut
		885
		886	sub _drain_wbuf {
		887	my ($self) = @_;
		888
		889	if (!$self->{_ww} && length $self->{wbuf}) {
		890
		891	Scalar::Util::weaken $self;
		892
		893	my $cb = sub {
		894	my $len = syswrite $self->{fh}, $self->{wbuf};
		895
		896	if (defined $len) {
		897	substr $self->{wbuf}, 0, $len, "";
		898
		899	$self->{_activity} = $self->{_wactivity} = AE::now;
		900
		901	$self->{on_drain}($self)
		902	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
		903	&& $self->{on_drain};
		904
		905	delete $self->{_ww} unless length $self->{wbuf};
		906	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		907	$self->_error ($!, 1);
		908	}
		909	};
		910
		911	# try to write data immediately
		912	$cb->() unless $self->{autocork};
		913
		914	# if still data left in wbuf, we need to poll
		915	$self->{_ww} = AE::io $self->{fh}, 1, $cb
		916	if length $self->{wbuf};
		917	};
		918	}
		919
		920	our %WH;
		921
		922	# deprecated
		923	sub register_write_type($$) {
		924	$WH{$_[0]} = $_[1];
		925	}
		926
		927	sub push_write {
		928	my $self = shift;
		929
		930	if (@_ > 1) {
		931	my $type = shift;
		932
		933	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
		934	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
		935	->($self, @_);
		936	}
		937
		938	# we downgrade here to avoid hard-to-track-down bugs,
		939	# and diagnose the problem earlier and better.
		940
		941	if ($self->{tls}) {
		942	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		943	&_dotls ($self) if $self->{fh};
		944	} else {
		945	utf8::downgrade $self->{wbuf} .= $_[0];
		946	$self->_drain_wbuf if $self->{fh};
		947	}
		948	}
		949
		950	=item $handle->push_write (type => @args)
		951
		952	Instead of formatting your data yourself, you can also let this module
		953	do the job by specifying a type and type-specific arguments. You
		954	can also specify the (fully qualified) name of a package, in which
		955	case AnyEvent tries to load the package and then expects to find the
		956	C<anyevent_write_type> function inside (see "custom write types", below).
		957
		958	Predefined types are (if you have ideas for additional types, feel free to
		959	drop by and tell us):
		960
		961	=over 4
		962
		963	=item netstring => $string
		964
		965	Formats the given value as netstring
		966	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		967
		968	=cut
		969
		970	register_write_type netstring => sub {
		971	my ($self, $string) = @_;
		972
		973	(length $string) . ":$string,"
		974	};
		975
		976	=item packstring => $format, $data
		977
		978	An octet string prefixed with an encoded length. The encoding C<$format>
		979	uses the same format as a Perl C<pack> format, but must specify a single
		980	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		981	optional C<!>, C<< < >> or C<< > >> modifier).
		982
		983	=cut
		984
		985	register_write_type packstring => sub {
		986	my ($self, $format, $string) = @_;
		987
		988	pack "$format/a*", $string
		989	};
		990
		991	=item json => $array_or_hashref
		992
		993	Encodes the given hash or array reference into a JSON object. Unless you
		994	provide your own JSON object, this means it will be encoded to JSON text
		995	in UTF-8.
		996
		997	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		998	one end of a handle and read them at the other end without using any
		999	additional framing.
		1000
		1001	The generated JSON text is guaranteed not to contain any newlines: While
		1002	this module doesn't need delimiters after or between JSON texts to be
		1003	able to read them, many other languages depend on that.
		1004
		1005	A simple RPC protocol that interoperates easily with others is to send
		1006	JSON arrays (or objects, although arrays are usually the better choice as
		1007	they mimic how function argument passing works) and a newline after each
		1008	JSON text:
		1009
		1010	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		1011	$handle->push_write ("\012");
		1012
		1013	An AnyEvent::Handle receiver would simply use the C<json> read type and
		1014	rely on the fact that the newline will be skipped as leading whitespace:
		1015
		1016	$handle->push_read (json => sub { my $array = $_[1]; ... });
		1017
		1018	Other languages could read single lines terminated by a newline and pass
		1019	this line into their JSON decoder of choice.
		1020
		1021	=cut
		1022
		1023	sub json_coder() {
		1024	eval { require JSON::XS; JSON::XS->new->utf8 }
		1025	|| do { require JSON; JSON->new->utf8 }
		1026	}
		1027
		1028	register_write_type json => sub {
		1029	my ($self, $ref) = @_;
		1030
		1031	my $json = $self->{json} ||= json_coder;
		1032
		1033	$json->encode ($ref)
		1034	};
		1035
		1036	=item storable => $reference
		1037
		1038	Freezes the given reference using L<Storable> and writes it to the
		1039	handle. Uses the C<nfreeze> format.
		1040
		1041	=cut
		1042
		1043	register_write_type storable => sub {
		1044	my ($self, $ref) = @_;
		1045
		1046	require Storable;
		1047
		1048	pack "w/a*", Storable::nfreeze ($ref)
		1049	};
		1050
		1051	=back
		1052
		1053	=item $handle->push_shutdown
		1054
		1055	Sometimes you know you want to close the socket after writing your data
		1056	before it was actually written. One way to do that is to replace your
		1057	C<on_drain> handler by a callback that shuts down the socket (and set
		1058	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1059	replaces the C<on_drain> callback with:
		1060
		1061	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		1062
		1063	This simply shuts down the write side and signals an EOF condition to the
		1064	the peer.
		1065
		1066	You can rely on the normal read queue and C<on_eof> handling
		1067	afterwards. This is the cleanest way to close a connection.
		1068
		1069	This method may invoke callbacks (and therefore the handle might be
		1070	destroyed after it returns).
		1071
		1072	=cut
		1073
		1074	sub push_shutdown {
		1075	my ($self) = @_;
		1076
		1077	delete $self->{low_water_mark};
		1078	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1079	}
		1080
		1081	=item custom write types - Package::anyevent_write_type $handle, @args
		1082
		1083	Instead of one of the predefined types, you can also specify the name of
		1084	a package. AnyEvent will try to load the package and then expects to find
		1085	a function named C<anyevent_write_type> inside. If it isn't found, it
		1086	progressively tries to load the parent package until it either finds the
		1087	function (good) or runs out of packages (bad).
		1088
		1089	Whenever the given C<type> is used, C<push_write> will the function with
		1090	the handle object and the remaining arguments.
		1091
		1092	The function is supposed to return a single octet string that will be
		1093	appended to the write buffer, so you cna mentally treat this function as a
		1094	"arguments to on-the-wire-format" converter.
		1095
		1096	Example: implement a custom write type C<join> that joins the remaining
		1097	arguments using the first one.
		1098
		1099	$handle->push_write (My::Type => " ", 1,2,3);
		1100
		1101	# uses the following package, which can be defined in the "My::Type" or in
		1102	# the "My" modules to be auto-loaded, or just about anywhere when the
		1103	# My::Type::anyevent_write_type is defined before invoking it.
		1104
		1105	package My::Type;
		1106
		1107	sub anyevent_write_type {
		1108	my ($handle, $delim, @args) = @_;
		1109
		1110	join $delim, @args
		1111	}
		1112
		1113	=cut
		1114
		1115	#############################################################################
		1116
		1117	=back
		1118
		1119	=head2 READ QUEUE
		1120
		1121	AnyEvent::Handle manages two queues per handle, one for writing and one
		1122	for reading.
		1123
		1124	The read queue is more complex than the write queue. It can be used in two
		1125	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		1126	a queue.
		1127
		1128	In the simple case, you just install an C<on_read> callback and whenever
		1129	new data arrives, it will be called. You can then remove some data (if
		1130	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
		1131	leave the data there if you want to accumulate more (e.g. when only a
		1132	partial message has been received so far), or change the read queue with
		1133	e.g. C<push_read>.
		1134
		1135	In the more complex case, you want to queue multiple callbacks. In this
		1136	case, AnyEvent::Handle will call the first queued callback each time new
		1137	data arrives (also the first time it is queued) and remove it when it has
		1138	done its job (see C<push_read>, below).
		1139
		1140	This way you can, for example, push three line-reads, followed by reading
		1141	a chunk of data, and AnyEvent::Handle will execute them in order.
		1142
		1143	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		1144	the specified number of bytes which give an XML datagram.
		1145
		1146	# in the default state, expect some header bytes
		1147	$handle->on_read (sub {
		1148	# some data is here, now queue the length-header-read (4 octets)
		1149	shift->unshift_read (chunk => 4, sub {
		1150	# header arrived, decode
		1151	my $len = unpack "N", $_[1];
		1152
		1153	# now read the payload
		1154	shift->unshift_read (chunk => $len, sub {
		1155	my $xml = $_[1];
		1156	# handle xml
		1157	});
		1158	});
		1159	});
		1160
		1161	Example 2: Implement a client for a protocol that replies either with "OK"
		1162	and another line or "ERROR" for the first request that is sent, and 64
		1163	bytes for the second request. Due to the availability of a queue, we can
		1164	just pipeline sending both requests and manipulate the queue as necessary
		1165	in the callbacks.
		1166
		1167	When the first callback is called and sees an "OK" response, it will
		1168	C<unshift> another line-read. This line-read will be queued I<before> the
		1169	64-byte chunk callback.
		1170
		1171	# request one, returns either "OK + extra line" or "ERROR"
		1172	$handle->push_write ("request 1\015\012");
		1173
		1174	# we expect "ERROR" or "OK" as response, so push a line read
		1175	$handle->push_read (line => sub {
		1176	# if we got an "OK", we have to _prepend_ another line,
		1177	# so it will be read before the second request reads its 64 bytes
		1178	# which are already in the queue when this callback is called
		1179	# we don't do this in case we got an error
		1180	if ($_[1] eq "OK") {
		1181	$_[0]->unshift_read (line => sub {
		1182	my $response = $_[1];
		1183	...
		1184	});
38	}	1185	}
39	});	1186	});
40		1187
41	# or use the constructor to pass the callback:	1188	# request two, simply returns 64 octets
		1189	$handle->push_write ("request 2\015\012");
42		1190
43	my $ae_fh2 =	1191	# simply read 64 bytes, always
44	AnyEvent::Handle->new (	1192	$handle->push_read (chunk => 64, sub {
45	fh => \*STDIN,	1193	my $response = $_[1];
46	on_eof => sub {	1194	...
47	$cv->broadcast;	1195	});
48	},	1196
49	on_readline => sub {	1197	=over 4
50	my ($ae_fh, @lines) = @_;	1198
51	for (@lines) {	1199	=cut
52	chomp;	1200
53	print "Line: $_";	1201	sub _drain_rbuf {
		1202	my ($self) = @_;
		1203
		1204	# avoid recursion
		1205	return if $self->{_skip_drain_rbuf};
		1206	local $self->{_skip_drain_rbuf} = 1;
		1207
		1208	while () {
		1209	# we need to use a separate tls read buffer, as we must not receive data while
		1210	# we are draining the buffer, and this can only happen with TLS.
		1211	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1212	if exists $self->{_tls_rbuf};
		1213
		1214	my $len = length $self->{rbuf};
		1215
		1216	if (my $cb = shift @{ $self->{_queue} }) {
		1217	unless ($cb->($self)) {
		1218	# no progress can be made
		1219	# (not enough data and no data forthcoming)
		1220	$self->_error (Errno::EPIPE, 1), return
		1221	if $self->{_eof};
		1222
		1223	unshift @{ $self->{_queue} }, $cb;
54	}	1224	last;
55	}	1225	}
56	);
57
58	$cv->wait;
59
60	=head1 DESCRIPTION
61
62	This module is a helper module to make it easier to do non-blocking I/O
63	on filehandles (and sockets, see L<AnyEvent::Socket>).
64
65	The event loop is provided by L<AnyEvent>.
66
67	=head1 METHODS
68
69	=over 4
70
71	=item B<new (%args)>
72
73	The constructor has these arguments:
74
75	=over 4
76
77	=item fh => $filehandle
78
79	The filehandle this L<AnyEvent::Handle> object will operate on.
80
81	NOTE: The filehandle will be set to non-blocking.
82
83	=item read_block_size => $size
84
85	The default read block size use for reads via the C<on_read>
86	method.
87
88	=item on_read => $cb
89
90	=item on_eof => $cb
91
92	=item on_error => $cb
93
94	These are shortcuts, that will call the corresponding method and set the callback to C<$cb>.
95
96	=item on_readline => $cb
97
98	The C<readlines> method is called with the default seperator and C<$cb> as callback
99	for you.
100
101	=back
102
103	=cut
104
105	sub new {
106	my $this = shift;
107	my $class = ref($this) || $this;
108	my $self = {
109	read_block_size => 4096,
110	rbuf => '',
111	@_
112	};
113	bless $self, $class;
114
115	$self->{fh}->blocking (0) if $self->{fh};
116
117	if ($self->{on_read}) {
118	$self->on_read ($self->{on_read});
119
120	} elsif ($self->{on_readline}) {	1226	} elsif ($self->{on_read}) {
121	$self->readlines ($self->{on_readline});	1227	last unless $len;
122		1228
		1229	$self->{on_read}($self);
		1230
		1231	if (
		1232	$len == length $self->{rbuf} # if no data has been consumed
		1233	&& !@{ $self->{_queue} } # and the queue is still empty
		1234	&& $self->{on_read} # but we still have on_read
		1235	) {
		1236	# no further data will arrive
		1237	# so no progress can be made
		1238	$self->_error (Errno::EPIPE, 1), return
		1239	if $self->{_eof};
		1240
		1241	last; # more data might arrive
		1242	}
		1243	} else {
		1244	# read side becomes idle
		1245	delete $self->{_rw} unless $self->{tls};
		1246	last;
		1247	}
		1248	}
		1249
123	} elsif ($self->{on_eof}) {	1250	if ($self->{_eof}) {
124	$self->on_eof ($self->{on_eof});	1251	$self->{on_eof}
		1252	? $self->{on_eof}($self)
		1253	: $self->_error (0, 1, "Unexpected end-of-file");
125		1254
126	} elsif ($self->{on_error}) {	1255	return;
127	$self->on_eof ($self->{on_error});
128	}	1256	}
129		1257
130	return $self	1258	if (
131	}	1259	defined $self->{rbuf_max}
		1260	&& $self->{rbuf_max} < length $self->{rbuf}
		1261	) {
		1262	$self->_error (Errno::ENOSPC, 1), return;
		1263	}
132		1264
133	=item B<fh>	1265	# may need to restart read watcher
		1266	unless ($self->{_rw}) {
		1267	$self->start_read
		1268	if $self->{on_read} || @{ $self->{_queue} };
		1269	}
		1270	}
134		1271
135	This method returns the filehandle of the L<AnyEvent::Handle> object.	1272	=item $handle->on_read ($cb)
136		1273
137	=cut	1274	This replaces the currently set C<on_read> callback, or clears it (when
		1275	the new callback is C<undef>). See the description of C<on_read> in the
		1276	constructor.
138		1277
139	sub fh { $_[0]->{fh} }	1278	This method may invoke callbacks (and therefore the handle might be
140		1279	destroyed after it returns).
141	=item B<on_read ($callback)>
142
143	This method installs a C<$callback> that will be called
144	when new data arrived. You can access the read buffer via the C<rbuf>
145	method (see below).
146
147	The first argument of the C<$callback> will be the L<AnyEvent::Handle> object.
148		1280
149	=cut	1281	=cut
150		1282
151	sub on_read {	1283	sub on_read {
152	my ($self, $cb) = @_;	1284	my ($self, $cb) = @_;
		1285
153	$self->{on_read} = $cb;	1286	$self->{on_read} = $cb;
		1287	$self->_drain_rbuf if $cb;
		1288	}
154		1289
155	unless (defined $self->{on_read}) {	1290	=item $handle->rbuf
156	delete $self->{on_read_w};	1291
		1292	Returns the read buffer (as a modifiable lvalue). You can also access the
		1293	read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
		1294	much faster, and no less clean).
		1295
		1296	The only operation allowed on the read buffer (apart from looking at it)
		1297	is removing data from its beginning. Otherwise modifying or appending to
		1298	it is not allowed and will lead to hard-to-track-down bugs.
		1299
		1300	NOTE: The read buffer should only be used or modified in the C<on_read>
		1301	callback or when C<push_read> or C<unshift_read> are used with a single
		1302	callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
		1303	will manage the read buffer on their own.
		1304
		1305	=cut
		1306
		1307	sub rbuf : lvalue {
		1308	$_[0]{rbuf}
		1309	}
		1310
		1311	=item $handle->push_read ($cb)
		1312
		1313	=item $handle->unshift_read ($cb)
		1314
		1315	Append the given callback to the end of the queue (C<push_read>) or
		1316	prepend it (C<unshift_read>).
		1317
		1318	The callback is called each time some additional read data arrives.
		1319
		1320	It must check whether enough data is in the read buffer already.
		1321
		1322	If not enough data is available, it must return the empty list or a false
		1323	value, in which case it will be called repeatedly until enough data is
		1324	available (or an error condition is detected).
		1325
		1326	If enough data was available, then the callback must remove all data it is
		1327	interested in (which can be none at all) and return a true value. After returning
		1328	true, it will be removed from the queue.
		1329
		1330	These methods may invoke callbacks (and therefore the handle might be
		1331	destroyed after it returns).
		1332
		1333	=cut
		1334
		1335	our %RH;
		1336
		1337	sub register_read_type($$) {
		1338	$RH{$_[0]} = $_[1];
		1339	}
		1340
		1341	sub push_read {
		1342	my $self = shift;
		1343	my $cb = pop;
		1344
		1345	if (@_) {
		1346	my $type = shift;
		1347
		1348	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
		1349	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
		1350	->($self, $cb, @_);
		1351	}
		1352
		1353	push @{ $self->{_queue} }, $cb;
		1354	$self->_drain_rbuf;
		1355	}
		1356
		1357	sub unshift_read {
		1358	my $self = shift;
		1359	my $cb = pop;
		1360
		1361	if (@_) {
		1362	my $type = shift;
		1363
		1364	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
		1365	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
		1366	->($self, $cb, @_);
		1367	}
		1368
		1369	unshift @{ $self->{_queue} }, $cb;
		1370	$self->_drain_rbuf;
		1371	}
		1372
		1373	=item $handle->push_read (type => @args, $cb)
		1374
		1375	=item $handle->unshift_read (type => @args, $cb)
		1376
		1377	Instead of providing a callback that parses the data itself you can chose
		1378	between a number of predefined parsing formats, for chunks of data, lines
		1379	etc. You can also specify the (fully qualified) name of a package, in
		1380	which case AnyEvent tries to load the package and then expects to find the
		1381	C<anyevent_read_type> function inside (see "custom read types", below).
		1382
		1383	Predefined types are (if you have ideas for additional types, feel free to
		1384	drop by and tell us):
		1385
		1386	=over 4
		1387
		1388	=item chunk => $octets, $cb->($handle, $data)
		1389
		1390	Invoke the callback only once C<$octets> bytes have been read. Pass the
		1391	data read to the callback. The callback will never be called with less
		1392	data.
		1393
		1394	Example: read 2 bytes.
		1395
		1396	$handle->push_read (chunk => 2, sub {
		1397	warn "yay ", unpack "H*", $_[1];
		1398	});
		1399
		1400	=cut
		1401
		1402	register_read_type chunk => sub {
		1403	my ($self, $cb, $len) = @_;
		1404
		1405	sub {
		1406	$len <= length $_[0]{rbuf} or return;
		1407	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
		1408	1
		1409	}
		1410	};
		1411
		1412	=item line => [$eol, ]$cb->($handle, $line, $eol)
		1413
		1414	The callback will be called only once a full line (including the end of
		1415	line marker, C<$eol>) has been read. This line (excluding the end of line
		1416	marker) will be passed to the callback as second argument (C<$line>), and
		1417	the end of line marker as the third argument (C<$eol>).
		1418
		1419	The end of line marker, C<$eol>, can be either a string, in which case it
		1420	will be interpreted as a fixed record end marker, or it can be a regex
		1421	object (e.g. created by C<qr>), in which case it is interpreted as a
		1422	regular expression.
		1423
		1424	The end of line marker argument C<$eol> is optional, if it is missing (NOT
		1425	undef), then C<qr|\015?\012|> is used (which is good for most internet
		1426	protocols).
		1427
		1428	Partial lines at the end of the stream will never be returned, as they are
		1429	not marked by the end of line marker.
		1430
		1431	=cut
		1432
		1433	register_read_type line => sub {
		1434	my ($self, $cb, $eol) = @_;
		1435
		1436	if (@_ < 3) {
		1437	# this is more than twice as fast as the generic code below
		1438	sub {
		1439	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		1440
		1441	$cb->($_[0], $1, $2);
		1442	1
		1443	}
		1444	} else {
		1445	$eol = quotemeta $eol unless ref $eol;
		1446	$eol = qr|^(.*?)($eol)|s;
		1447
		1448	sub {
		1449	$_[0]{rbuf} =~ s/$eol// or return;
		1450
		1451	$cb->($_[0], $1, $2);
		1452	1
		1453	}
		1454	}
		1455	};
		1456
		1457	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1458
		1459	Makes a regex match against the regex object C<$accept> and returns
		1460	everything up to and including the match.
		1461
		1462	Example: read a single line terminated by '\n'.
		1463
		1464	$handle->push_read (regex => qr<\n>, sub { ... });
		1465
		1466	If C<$reject> is given and not undef, then it determines when the data is
		1467	to be rejected: it is matched against the data when the C<$accept> regex
		1468	does not match and generates an C<EBADMSG> error when it matches. This is
		1469	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1470	receive buffer overflow).
		1471
		1472	Example: expect a single decimal number followed by whitespace, reject
		1473	anything else (not the use of an anchor).
		1474
		1475	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1476
		1477	If C<$skip> is given and not C<undef>, then it will be matched against
		1478	the receive buffer when neither C<$accept> nor C<$reject> match,
		1479	and everything preceding and including the match will be accepted
		1480	unconditionally. This is useful to skip large amounts of data that you
		1481	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1482	have to start matching from the beginning. This is purely an optimisation
		1483	and is usually worth it only when you expect more than a few kilobytes.
		1484
		1485	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1486	expect the header to be very large (it isn't in practice, but...), we use
		1487	a skip regex to skip initial portions. The skip regex is tricky in that
		1488	it only accepts something not ending in either \015 or \012, as these are
		1489	required for the accept regex.
		1490
		1491	$handle->push_read (regex =>
		1492	qr<\015\012\015\012>,
		1493	undef, # no reject
		1494	qr<^.*[^\015\012]>,
		1495	sub { ... });
		1496
		1497	=cut
		1498
		1499	register_read_type regex => sub {
		1500	my ($self, $cb, $accept, $reject, $skip) = @_;
		1501
		1502	my $data;
		1503	my $rbuf = \$self->{rbuf};
		1504
		1505	sub {
		1506	# accept
		1507	if ($$rbuf =~ $accept) {
		1508	$data .= substr $$rbuf, 0, $+[0], "";
		1509	$cb->($self, $data);
		1510	return 1;
		1511	}
		1512
		1513	# reject
		1514	if ($reject && $$rbuf =~ $reject) {
		1515	$self->_error (Errno::EBADMSG);
		1516	}
		1517
		1518	# skip
		1519	if ($skip && $$rbuf =~ $skip) {
		1520	$data .= substr $$rbuf, 0, $+[0], "";
		1521	}
		1522
		1523	()
		1524	}
		1525	};
		1526
		1527	=item netstring => $cb->($handle, $string)
		1528
		1529	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1530
		1531	Throws an error with C<$!> set to EBADMSG on format violations.
		1532
		1533	=cut
		1534
		1535	register_read_type netstring => sub {
		1536	my ($self, $cb) = @_;
		1537
		1538	sub {
		1539	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1540	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1541	$self->_error (Errno::EBADMSG);
		1542	}
157	return;	1543	return;
		1544	}
		1545
		1546	my $len = $1;
		1547
		1548	$self->unshift_read (chunk => $len, sub {
		1549	my $string = $_[1];
		1550	$_[0]->unshift_read (chunk => 1, sub {
		1551	if ($_[1] eq ",") {
		1552	$cb->($_[0], $string);
		1553	} else {
		1554	$self->_error (Errno::EBADMSG);
		1555	}
		1556	});
		1557	});
		1558
		1559	1
		1560	}
		1561	};
		1562
		1563	=item packstring => $format, $cb->($handle, $string)
		1564
		1565	An octet string prefixed with an encoded length. The encoding C<$format>
		1566	uses the same format as a Perl C<pack> format, but must specify a single
		1567	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1568	optional C<!>, C<< < >> or C<< > >> modifier).
		1569
		1570	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1571	EPP uses a prefix of C<N> (4 octtes).
		1572
		1573	Example: read a block of data prefixed by its length in BER-encoded
		1574	format (very efficient).
		1575
		1576	$handle->push_read (packstring => "w", sub {
		1577	my ($handle, $data) = @_;
158	}	1578	});
159		1579
160	$self->{on_read_w} =	1580	=cut
161	AnyEvent->io (poll => 'r', fh => $self->{fh}, cb => sub {	1581
162	#d# warn "READ:[$self->{read_size}] $self->{read_block_size} : ".length ($self->{rbuf})."\n";	1582	register_read_type packstring => sub {
		1583	my ($self, $cb, $format) = @_;
		1584
		1585	sub {
		1586	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1587	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1588	or return;
		1589
		1590	$format = length pack $format, $len;
		1591
		1592	# bypass unshift if we already have the remaining chunk
		1593	if ($format + $len <= length $_[0]{rbuf}) {
		1594	my $data = substr $_[0]{rbuf}, $format, $len;
		1595	substr $_[0]{rbuf}, 0, $format + $len, "";
		1596	$cb->($_[0], $data);
		1597	} else {
		1598	# remove prefix
		1599	substr $_[0]{rbuf}, 0, $format, "";
		1600
		1601	# read remaining chunk
		1602	$_[0]->unshift_read (chunk => $len, $cb);
		1603	}
		1604
		1605	1
		1606	}
		1607	};
		1608
		1609	=item json => $cb->($handle, $hash_or_arrayref)
		1610
		1611	Reads a JSON object or array, decodes it and passes it to the
		1612	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1613
		1614	If a C<json> object was passed to the constructor, then that will be used
		1615	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1616
		1617	This read type uses the incremental parser available with JSON version
		1618	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1619	dependency on your own: this module will load the JSON module, but
		1620	AnyEvent does not depend on it itself.
		1621
		1622	Since JSON texts are fully self-delimiting, the C<json> read and write
		1623	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1624	the C<json> write type description, above, for an actual example.
		1625
		1626	=cut
		1627
		1628	register_read_type json => sub {
		1629	my ($self, $cb) = @_;
		1630
		1631	my $json = $self->{json} ||= json_coder;
		1632
		1633	my $data;
163	my $rbuf_len = length $self->{rbuf};	1634	my $rbuf = \$self->{rbuf};
164	my $l;	1635
		1636	sub {
		1637	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
		1638
		1639	if ($ref) {
		1640	$self->{rbuf} = $json->incr_text;
		1641	$json->incr_text = "";
		1642	$cb->($self, $ref);
		1643
		1644	1
		1645	} elsif ($@) {
		1646	# error case
		1647	$json->incr_skip;
		1648
		1649	$self->{rbuf} = $json->incr_text;
		1650	$json->incr_text = "";
		1651
		1652	$self->_error (Errno::EBADMSG);
		1653
		1654	()
		1655	} else {
		1656	$self->{rbuf} = "";
		1657
		1658	()
		1659	}
		1660	}
		1661	};
		1662
		1663	=item storable => $cb->($handle, $ref)
		1664
		1665	Deserialises a L<Storable> frozen representation as written by the
		1666	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1667	data).
		1668
		1669	Raises C<EBADMSG> error if the data could not be decoded.
		1670
		1671	=cut
		1672
		1673	register_read_type storable => sub {
		1674	my ($self, $cb) = @_;
		1675
		1676	require Storable;
		1677
		1678	sub {
		1679	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1680	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1681	or return;
		1682
		1683	my $format = length pack "w", $len;
		1684
		1685	# bypass unshift if we already have the remaining chunk
		1686	if ($format + $len <= length $_[0]{rbuf}) {
		1687	my $data = substr $_[0]{rbuf}, $format, $len;
		1688	substr $_[0]{rbuf}, 0, $format + $len, "";
		1689	$cb->($_[0], Storable::thaw ($data));
		1690	} else {
		1691	# remove prefix
		1692	substr $_[0]{rbuf}, 0, $format, "";
		1693
		1694	# read remaining chunk
		1695	$_[0]->unshift_read (chunk => $len, sub {
		1696	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1697	$cb->($_[0], $ref);
		1698	} else {
		1699	$self->_error (Errno::EBADMSG);
		1700	}
		1701	});
		1702	}
		1703
		1704	1
		1705	}
		1706	};
		1707
		1708	=back
		1709
		1710	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
		1711
		1712	Instead of one of the predefined types, you can also specify the name
		1713	of a package. AnyEvent will try to load the package and then expects to
		1714	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1715	progressively tries to load the parent package until it either finds the
		1716	function (good) or runs out of packages (bad).
		1717
		1718	Whenever this type is used, C<push_read> will invoke the function with the
		1719	handle object, the original callback and the remaining arguments.
		1720
		1721	The function is supposed to return a callback (usually a closure) that
		1722	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1723	mentally treat the function as a "configurable read type to read callback"
		1724	converter.
		1725
		1726	It should invoke the original callback when it is done reading (remember
		1727	to pass C<$handle> as first argument as all other callbacks do that,
		1728	although there is no strict requirement on this).
		1729
		1730	For examples, see the source of this module (F<perldoc -m
		1731	AnyEvent::Handle>, search for C<register_read_type>)).
		1732
		1733	=item $handle->stop_read
		1734
		1735	=item $handle->start_read
		1736
		1737	In rare cases you actually do not want to read anything from the
		1738	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
		1739	any queued callbacks will be executed then. To start reading again, call
		1740	C<start_read>.
		1741
		1742	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1743	you change the C<on_read> callback or push/unshift a read callback, and it
		1744	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1745	there are any read requests in the queue.
		1746
		1747	These methods will have no effect when in TLS mode (as TLS doesn't support
		1748	half-duplex connections).
		1749
		1750	=cut
		1751
		1752	sub stop_read {
		1753	my ($self) = @_;
		1754
		1755	delete $self->{_rw} unless $self->{tls};
		1756	}
		1757
		1758	sub start_read {
		1759	my ($self) = @_;
		1760
		1761	unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
		1762	Scalar::Util::weaken $self;
		1763
		1764	$self->{_rw} = AE::io $self->{fh}, 0, sub {
		1765	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
		1766	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
		1767
		1768	if ($len > 0) {
		1769	$self->{_activity} = $self->{_ractivity} = AE::now;
		1770
		1771	if ($self->{tls}) {
		1772	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1773
		1774	&_dotls ($self);
		1775	} else {
		1776	$self->_drain_rbuf;
		1777	}
		1778
165	if (defined $self->{read_size}) {	1779	if ($len == $self->{read_size}) {
166	$l = sysread $self->{fh}, $self->{rbuf},	1780	$self->{read_size} *= 2;
167	($self->{read_size} - $rbuf_len), $rbuf_len;	1781	$self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
		1782	if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
		1783	}
		1784
		1785	} elsif (defined $len) {
		1786	delete $self->{_rw};
		1787	$self->{_eof} = 1;
		1788	$self->_drain_rbuf;
		1789
		1790	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		1791	return $self->_error ($!, 1);
		1792	}
		1793	};
		1794	}
		1795	}
		1796
		1797	our $ERROR_SYSCALL;
		1798	our $ERROR_WANT_READ;
		1799
		1800	sub _tls_error {
		1801	my ($self, $err) = @_;
		1802
		1803	return $self->_error ($!, 1)
		1804	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1805
		1806	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1807
		1808	# reduce error string to look less scary
		1809	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1810
		1811	if ($self->{_on_starttls}) {
		1812	(delete $self->{_on_starttls})->($self, undef, $err);
		1813	&_freetls;
		1814	} else {
		1815	&_freetls;
		1816	$self->_error (Errno::EPROTO, 1, $err);
		1817	}
		1818	}
		1819
		1820	# poll the write BIO and send the data if applicable
		1821	# also decode read data if possible
		1822	# this is basiclaly our TLS state machine
		1823	# more efficient implementations are possible with openssl,
		1824	# but not with the buggy and incomplete Net::SSLeay.
		1825	sub _dotls {
		1826	my ($self) = @_;
		1827
		1828	my $tmp;
		1829
		1830	if (length $self->{_tls_wbuf}) {
		1831	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		1832	substr $self->{_tls_wbuf}, 0, $tmp, "";
		1833	}
		1834
		1835	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1836	return $self->_tls_error ($tmp)
		1837	if $tmp != $ERROR_WANT_READ
		1838	&& ($tmp != $ERROR_SYSCALL || $!);
		1839	}
		1840
		1841	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1842	unless (length $tmp) {
		1843	$self->{_on_starttls}
		1844	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1845	&_freetls;
		1846
		1847	if ($self->{on_stoptls}) {
		1848	$self->{on_stoptls}($self);
		1849	return;
168	} else {	1850	} else {
169	$l = sysread $self->{fh}, $self->{rbuf}, $self->{read_block_size}, $rbuf_len;	1851	# let's treat SSL-eof as we treat normal EOF
170	}
171	#d# warn "READL $l [$self->{rbuf}]\n";
172
173	if (not defined $l) {
174	return if $! == EAGAIN || $! == EINTR;
175	$self->{on_error}->($self) if $self->{on_error};
176	delete $self->{on_read_w};	1852	delete $self->{_rw};
177
178	} elsif ($l == 0) {
179	$self->{on_eof}->($self) if $self->{on_eof};
180	delete $self->{on_read_w};
181
182	} else {
183	$self->{on_read}->($self);
184	}
185	});
186	}
187
188	=item B<on_error ($callback)>
189
190	Whenever a read or write operation resulted in an error the C<$callback>
191	will be called.
192
193	The first argument of C<$callback> will be the L<AnyEvent::Handle> object itself.
194	The error is given as errno in C<$!>.
195
196	=cut
197
198	sub on_error {
199	$_[0]->{on_error} = $_[1];
200	}
201
202	=item B<on_eof ($callback)>
203
204	Installs the C<$callback> that will be called when the end of file is
205	encountered in a read operation this C<$callback> will be called. The first
206	argument will be the L<AnyEvent::Handle> object itself.
207
208	=cut
209
210	sub on_eof {
211	$_[0]->{on_eof} = $_[1];
212	}
213
214	=item B<rbuf>
215
216	Returns a reference to the read buffer.
217
218	NOTE: The read buffer should only be used or modified if the C<on_read>
219	method is used directly. The C<read> and C<readlines> methods will provide
220	the read data to their callbacks.
221
222	=cut
223
224	sub rbuf : lvalue {
225	$_[0]->{rbuf}
226	}
227
228	=item B<read ($len, $callback)>
229
230	Will read exactly C<$len> bytes from the filehandle and call the C<$callback>
231	if done so. The first argument to the C<$callback> will be the L<AnyEvent::Handle>
232	object itself and the second argument the read data.
233
234	NOTE: This method will override any callbacks installed via the C<on_read> method.
235
236	=cut
237
238	sub read {
239	my ($self, $len, $cb) = @_;
240
241	$self->{read_cb} = $cb;
242	my $old_blk_size = $self->{read_block_size};
243	$self->{read_block_size} = $len;
244
245	$self->on_read (sub {
246	#d# warn "OFOFO $len || ".length($_[0]->{rbuf})."||\n";
247
248	if ($len == length $_[0]->{rbuf}) {
249	$_[0]->{read_block_size} = $old_blk_size;
250	$_[0]->on_read (undef);
251	$_[0]->{read_cb}->($_[0], (substr $self->{rbuf}, 0, $len, ''));
252	}
253	});
254	}
255
256	=item B<readlines ($callback)>
257
258	=item B<readlines ($sep, $callback)>
259
260	This method will read lines from the filehandle, seperated by C<$sep> or C<"\n">
261	if C<$sep> is not provided. C<$sep> will be used as part of a regex, so it can be
262	a regex itself and won't be quoted!
263
264	The C<$callback> will be called when at least one
265	line could be read. The first argument to the C<$callback> will be the L<AnyEvent::Handle>
266	object itself and the rest of the arguments will be the read lines.
267
268	NOTE: This method will override any callbacks installed via the C<on_read> method.
269
270	=cut
271
272	sub readlines {
273	my ($self, $NL, $cb) = @_;
274
275	if (ref $NL) {
276	$cb = $NL;
277	$NL = "\n";
278	}
279
280	$self->{on_readline} = $cb;
281
282	$self->on_read (sub {
283	my @lines;
284	push @lines, $1 while $_[0]->{rbuf} =~ s/(.*)$NL//;
285	$self->{on_readline}->($_[0], @lines);
286	});
287	}
288
289	=item B<write ($data)>
290
291	=item B<write ($callback)>
292
293	=item B<write ($data, $callback)>
294
295	This method will write C<$data> to the filehandle and call the C<$callback>
296	afterwards. If only C<$callback> is provided it will be called when the
297	write buffer becomes empty the next time (or immediately if it already is empty).
298
299	=cut
300
301	sub write {
302	my ($self, $data, $cb) = @_;
303	if (ref $data) { $cb = $data; undef $data }
304	push @{$self->{write_bufs}}, [$data, $cb];
305	$self->_check_writer;
306	}
307
308	sub _check_writer {
309	my ($self) = @_;
310
311	if ($self->{write_w}) {
312	unless ($self->{write_cb}) {
313	while (@{$self->{write_bufs}} && not defined $self->{write_bufs}->[0]->[1]) {
314	my $wba = shift @{$self->{write_bufs}};
315	$self->{wbuf} .= $wba->[0];	1853	$self->{_eof} = 1;
316	}	1854	}
317	}	1855	}
318	return;
319	}
320		1856
321	my $wba = shift @{$self->{write_bufs}}	1857	$self->{_tls_rbuf} .= $tmp;
322	or return;	1858	$self->_drain_rbuf;
323		1859	$self->{tls} or return; # tls session might have gone away in callback
324	unless (defined $wba->[0]) {
325	$wba->[1]->($self) if $wba->[1];
326	$self->_check_writer;
327	return;
328	}	1860	}
329		1861
330	$self->{wbuf} = $wba->[0];	1862	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
331	$self->{write_cb} = $wba->[1];	1863	return $self->_tls_error ($tmp)
		1864	if $tmp != $ERROR_WANT_READ
		1865	&& ($tmp != $ERROR_SYSCALL || $!);
332		1866
333	$self->{write_w} =	1867	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
334	AnyEvent->io (poll => 'w', fh => $self->{fh}, cb => sub {	1868	$self->{wbuf} .= $tmp;
335	my $l = syswrite $self->{fh}, $self->{wbuf}, length $self->{wbuf};	1869	$self->_drain_wbuf;
		1870	$self->{tls} or return; # tls session might have gone away in callback
		1871	}
336		1872
337	if (not defined $l) {	1873	$self->{_on_starttls}
338	return if $! == EAGAIN || $! == EINTR;	1874	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
339	delete $self->{write_w};	1875	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
340	$self->{on_error}->($self) if $self->{on_error};	1876	}
341		1877
		1878	=item $handle->starttls ($tls[, $tls_ctx])
		1879
		1880	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1881	object is created, you can also do that at a later time by calling
		1882	C<starttls>.
		1883
		1884	Starting TLS is currently an asynchronous operation - when you push some
		1885	write data and then call C<< ->starttls >> then TLS negotiation will start
		1886	immediately, after which the queued write data is then sent.
		1887
		1888	The first argument is the same as the C<tls> constructor argument (either
		1889	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1890
		1891	The second argument is the optional C<AnyEvent::TLS> object that is used
		1892	when AnyEvent::Handle has to create its own TLS connection object, or
		1893	a hash reference with C<< key => value >> pairs that will be used to
		1894	construct a new context.
		1895
		1896	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
		1897	context in C<< $handle->{tls_ctx} >> after this call and can be used or
		1898	changed to your liking. Note that the handshake might have already started
		1899	when this function returns.
		1900
		1901	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1902	handshakes on the same stream. It is best to not attempt to use the
		1903	stream after stopping TLS.
		1904
		1905	This method may invoke callbacks (and therefore the handle might be
		1906	destroyed after it returns).
		1907
		1908	=cut
		1909
		1910	our %TLS_CACHE; #TODO not yet documented, should we?
		1911
		1912	sub starttls {
		1913	my ($self, $tls, $ctx) = @_;
		1914
		1915	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1916	if $self->{tls};
		1917
		1918	$self->{tls} = $tls;
		1919	$self->{tls_ctx} = $ctx if @_ > 2;
		1920
		1921	return unless $self->{fh};
		1922
		1923	require Net::SSLeay;
		1924
		1925	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		1926	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1927
		1928	$tls = delete $self->{tls};
		1929	$ctx = $self->{tls_ctx};
		1930
		1931	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1932
		1933	if ("HASH" eq ref $ctx) {
		1934	require AnyEvent::TLS;
		1935
		1936	if ($ctx->{cache}) {
		1937	my $key = $ctx+0;
		1938	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
342	} else {	1939	} else {
		1940	$ctx = new AnyEvent::TLS %$ctx;
		1941	}
		1942	}
		1943
		1944	$self->{tls_ctx} = $ctx || TLS_CTX ();
		1945	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
		1946
		1947	# basically, this is deep magic (because SSL_read should have the same issues)
		1948	# but the openssl maintainers basically said: "trust us, it just works".
		1949	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1950	# and mismaintained ssleay-module doesn't even offer them).
		1951	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1952	#
		1953	# in short: this is a mess.
		1954	#
		1955	# note that we do not try to keep the length constant between writes as we are required to do.
		1956	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1957	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1958	# have identity issues in that area.
		1959	# Net::SSLeay::CTX_set_mode ($ssl,
		1960	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1961	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1962	Net::SSLeay::CTX_set_mode ($tls, 1|2);
		1963
		1964	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1965	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1966
		1967	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		1968
		1969	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
		1970
		1971	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
		1972	if $self->{on_starttls};
		1973
		1974	&_dotls; # need to trigger the initial handshake
		1975	$self->start_read; # make sure we actually do read
		1976	}
		1977
		1978	=item $handle->stoptls
		1979
		1980	Shuts down the SSL connection - this makes a proper EOF handshake by
		1981	sending a close notify to the other side, but since OpenSSL doesn't
		1982	support non-blocking shut downs, it is not guaranteed that you can re-use
		1983	the stream afterwards.
		1984
		1985	This method may invoke callbacks (and therefore the handle might be
		1986	destroyed after it returns).
		1987
		1988	=cut
		1989
		1990	sub stoptls {
		1991	my ($self) = @_;
		1992
		1993	if ($self->{tls} && $self->{fh}) {
		1994	Net::SSLeay::shutdown ($self->{tls});
		1995
		1996	&_dotls;
		1997
		1998	# # we don't give a shit. no, we do, but we can't. no...#d#
		1999	# # we, we... have to use openssl :/#d#
		2000	# &_freetls;#d#
		2001	}
		2002	}
		2003
		2004	sub _freetls {
		2005	my ($self) = @_;
		2006
		2007	return unless $self->{tls};
		2008
		2009	$self->{tls_ctx}->_put_session (delete $self->{tls})
		2010	if $self->{tls} > 0;
		2011
		2012	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		2013	}
		2014
		2015	sub DESTROY {
		2016	my ($self) = @_;
		2017
		2018	&_freetls;
		2019
		2020	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		2021
		2022	if ($linger && length $self->{wbuf} && $self->{fh}) {
		2023	my $fh = delete $self->{fh};
		2024	my $wbuf = delete $self->{wbuf};
		2025
		2026	my @linger;
		2027
		2028	push @linger, AE::io $fh, 1, sub {
		2029	my $len = syswrite $fh, $wbuf, length $wbuf;
		2030
		2031	if ($len > 0) {
343	substr $self->{wbuf}, 0, $l, '';	2032	substr $wbuf, 0, $len, "";
344		2033	} elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
345	if (length ($self->{wbuf}) == 0) {	2034	@linger = (); # end
346	$self->{write_cb}->($self) if $self->{write_cb};
347
348	delete $self->{write_w};
349	delete $self->{wbuf};
350	delete $self->{write_cb};
351
352	$self->_check_writer;
353	}
354	}	2035	}
355	});	2036	};
		2037	push @linger, AE::timer $linger, 0, sub {
		2038	@linger = ();
		2039	};
		2040	}
		2041	}
		2042
		2043	=item $handle->destroy
		2044
		2045	Shuts down the handle object as much as possible - this call ensures that
		2046	no further callbacks will be invoked and as many resources as possible
		2047	will be freed. Any method you will call on the handle object after
		2048	destroying it in this way will be silently ignored (and it will return the
		2049	empty list).
		2050
		2051	Normally, you can just "forget" any references to an AnyEvent::Handle
		2052	object and it will simply shut down. This works in fatal error and EOF
		2053	callbacks, as well as code outside. It does I<NOT> work in a read or write
		2054	callback, so when you want to destroy the AnyEvent::Handle object from
		2055	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2056	that case.
		2057
		2058	Destroying the handle object in this way has the advantage that callbacks
		2059	will be removed as well, so if those are the only reference holders (as
		2060	is common), then one doesn't need to do anything special to break any
		2061	reference cycles.
		2062
		2063	The handle might still linger in the background and write out remaining
		2064	data, as specified by the C<linger> option, however.
		2065
		2066	=cut
		2067
		2068	sub destroy {
		2069	my ($self) = @_;
		2070
		2071	$self->DESTROY;
		2072	%$self = ();
		2073	bless $self, "AnyEvent::Handle::destroyed";
		2074	}
		2075
		2076	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2077	#nop
		2078	}
		2079
		2080	=item $handle->destroyed
		2081
		2082	Returns false as long as the handle hasn't been destroyed by a call to C<<
		2083	->destroy >>, true otherwise.
		2084
		2085	Can be useful to decide whether the handle is still valid after some
		2086	callback possibly destroyed the handle. For example, C<< ->push_write >>,
		2087	C<< ->starttls >> and other methods can call user callbacks, which in turn
		2088	can destroy the handle, so work can be avoided by checking sometimes:
		2089
		2090	$hdl->starttls ("accept");
		2091	return if $hdl->destroyed;
		2092	$hdl->push_write (...
		2093
		2094	Note that the call to C<push_write> will silently be ignored if the handle
		2095	has been destroyed, so often you can just ignore the possibility of the
		2096	handle being destroyed.
		2097
		2098	=cut
		2099
		2100	sub destroyed { 0 }
		2101	sub AnyEvent::Handle::destroyed::destroyed { 1 }
		2102
		2103	=item AnyEvent::Handle::TLS_CTX
		2104
		2105	This function creates and returns the AnyEvent::TLS object used by default
		2106	for TLS mode.
		2107
		2108	The context is created by calling L<AnyEvent::TLS> without any arguments.
		2109
		2110	=cut
		2111
		2112	our $TLS_CTX;
		2113
		2114	sub TLS_CTX() {
		2115	$TLS_CTX ||= do {
		2116	require AnyEvent::TLS;
		2117
		2118	new AnyEvent::TLS
		2119	}
356	}	2120	}
357		2121
358	=back	2122	=back
359		2123
		2124
		2125	=head1 NONFREQUENTLY ASKED QUESTIONS
		2126
		2127	=over 4
		2128
		2129	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2130	still get further invocations!
		2131
		2132	That's because AnyEvent::Handle keeps a reference to itself when handling
		2133	read or write callbacks.
		2134
		2135	It is only safe to "forget" the reference inside EOF or error callbacks,
		2136	from within all other callbacks, you need to explicitly call the C<<
		2137	->destroy >> method.
		2138
		2139	=item I get different callback invocations in TLS mode/Why can't I pause
		2140	reading?
		2141
		2142	Unlike, say, TCP, TLS connections do not consist of two independent
		2143	communication channels, one for each direction. Or put differently, the
		2144	read and write directions are not independent of each other: you cannot
		2145	write data unless you are also prepared to read, and vice versa.
		2146
		2147	This means that, in TLS mode, you might get C<on_error> or C<on_eof>
		2148	callback invocations when you are not expecting any read data - the reason
		2149	is that AnyEvent::Handle always reads in TLS mode.
		2150
		2151	During the connection, you have to make sure that you always have a
		2152	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2153	connection (or when you no longer want to use it) you can call the
		2154	C<destroy> method.
		2155
		2156	=item How do I read data until the other side closes the connection?
		2157
		2158	If you just want to read your data into a perl scalar, the easiest way
		2159	to achieve this is by setting an C<on_read> callback that does nothing,
		2160	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2161	will be in C<$_[0]{rbuf}>:
		2162
		2163	$handle->on_read (sub { });
		2164	$handle->on_eof (undef);
		2165	$handle->on_error (sub {
		2166	my $data = delete $_[0]{rbuf};
		2167	});
		2168
		2169	The reason to use C<on_error> is that TCP connections, due to latencies
		2170	and packets loss, might get closed quite violently with an error, when in
		2171	fact all data has been received.
		2172
		2173	It is usually better to use acknowledgements when transferring data,
		2174	to make sure the other side hasn't just died and you got the data
		2175	intact. This is also one reason why so many internet protocols have an
		2176	explicit QUIT command.
		2177
		2178	=item I don't want to destroy the handle too early - how do I wait until
		2179	all data has been written?
		2180
		2181	After writing your last bits of data, set the C<on_drain> callback
		2182	and destroy the handle in there - with the default setting of
		2183	C<low_water_mark> this will be called precisely when all data has been
		2184	written to the socket:
		2185
		2186	$handle->push_write (...);
		2187	$handle->on_drain (sub {
		2188	warn "all data submitted to the kernel\n";
		2189	undef $handle;
		2190	});
		2191
		2192	If you just want to queue some data and then signal EOF to the other side,
		2193	consider using C<< ->push_shutdown >> instead.
		2194
		2195	=item I want to contact a TLS/SSL server, I don't care about security.
		2196
		2197	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2198	connect to it and then create the AnyEvent::Handle with the C<tls>
		2199	parameter:
		2200
		2201	tcp_connect $host, $port, sub {
		2202	my ($fh) = @_;
		2203
		2204	my $handle = new AnyEvent::Handle
		2205	fh => $fh,
		2206	tls => "connect",
		2207	on_error => sub { ... };
		2208
		2209	$handle->push_write (...);
		2210	};
		2211
		2212	=item I want to contact a TLS/SSL server, I do care about security.
		2213
		2214	Then you should additionally enable certificate verification, including
		2215	peername verification, if the protocol you use supports it (see
		2216	L<AnyEvent::TLS>, C<verify_peername>).
		2217
		2218	E.g. for HTTPS:
		2219
		2220	tcp_connect $host, $port, sub {
		2221	my ($fh) = @_;
		2222
		2223	my $handle = new AnyEvent::Handle
		2224	fh => $fh,
		2225	peername => $host,
		2226	tls => "connect",
		2227	tls_ctx => { verify => 1, verify_peername => "https" },
		2228	...
		2229
		2230	Note that you must specify the hostname you connected to (or whatever
		2231	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2232	peername verification will be done.
		2233
		2234	The above will use the system-dependent default set of trusted CA
		2235	certificates. If you want to check against a specific CA, add the
		2236	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2237
		2238	tls_ctx => {
		2239	verify => 1,
		2240	verify_peername => "https",
		2241	ca_file => "my-ca-cert.pem",
		2242	},
		2243
		2244	=item I want to create a TLS/SSL server, how do I do that?
		2245
		2246	Well, you first need to get a server certificate and key. You have
		2247	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2248	self-signed certificate (cheap. check the search engine of your choice,
		2249	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2250	nice program for that purpose).
		2251
		2252	Then create a file with your private key (in PEM format, see
		2253	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2254	file should then look like this:
		2255
		2256	-----BEGIN RSA PRIVATE KEY-----
		2257	...header data
		2258	... lots of base64'y-stuff
		2259	-----END RSA PRIVATE KEY-----
		2260
		2261	-----BEGIN CERTIFICATE-----
		2262	... lots of base64'y-stuff
		2263	-----END CERTIFICATE-----
		2264
		2265	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2266	specify this file as C<cert_file>:
		2267
		2268	tcp_server undef, $port, sub {
		2269	my ($fh) = @_;
		2270
		2271	my $handle = new AnyEvent::Handle
		2272	fh => $fh,
		2273	tls => "accept",
		2274	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2275	...
		2276
		2277	When you have intermediate CA certificates that your clients might not
		2278	know about, just append them to the C<cert_file>.
		2279
		2280	=back
		2281
		2282
		2283	=head1 SUBCLASSING AnyEvent::Handle
		2284
		2285	In many cases, you might want to subclass AnyEvent::Handle.
		2286
		2287	To make this easier, a given version of AnyEvent::Handle uses these
		2288	conventions:
		2289
		2290	=over 4
		2291
		2292	=item * all constructor arguments become object members.
		2293
		2294	At least initially, when you pass a C<tls>-argument to the constructor it
		2295	will end up in C<< $handle->{tls} >>. Those members might be changed or
		2296	mutated later on (for example C<tls> will hold the TLS connection object).
		2297
		2298	=item * other object member names are prefixed with an C<_>.
		2299
		2300	All object members not explicitly documented (internal use) are prefixed
		2301	with an underscore character, so the remaining non-C<_>-namespace is free
		2302	for use for subclasses.
		2303
		2304	=item * all members not documented here and not prefixed with an underscore
		2305	are free to use in subclasses.
		2306
		2307	Of course, new versions of AnyEvent::Handle may introduce more "public"
		2308	member variables, but that's just life. At least it is documented.
		2309
		2310	=back
		2311
360	=head1 AUTHOR	2312	=head1 AUTHOR
361		2313
362	Robin Redeker, C<< <elmex at ta-sa.org> >>	2314	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
363		2315
364	=cut	2316	=cut
365		2317
366	1; # End of AnyEvent::Handle	2318	1; # End of AnyEvent::Handle

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