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Revision 1.2 by elmex, Sun Apr 27 17:27:34 2008 UTC vs.
Revision 1.178 by root, Tue Aug 11 01:15:17 2009 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 file 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 module is a helper module to make it easier to do event-based I/O on
		36	filehandles.
		37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
		40
		41	In the following, when the documentation refers to of "bytes" then this
		42	means 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	=head1 METHODS
		66
		67	=over 4
		68
		69	=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
		70
		71	The constructor supports these arguments (all as C<< key => value >> pairs).
		72
		73	=over 4
		74
		75	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
		76
		77	The filehandle this L<AnyEvent::Handle> object will operate on.
		78	NOTE: The filehandle will be set to non-blocking mode (using
		79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
		81
		82	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
		83
		84	Try to connect to the specified host and service (port), using
		85	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		86	default C<peername>.
		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
		99	=item on_prepare => $cb->($handle)
		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, $message)
		138
		139	This is the error callback, which is called when, well, some error
		140	occured, such as not being able to resolve the hostname, failure to
		141	connect or a read error.
		142
		143	Some errors are fatal (which is indicated by C<$fatal> being true). On
		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>).
		160
		161	On callback entrance, the value of C<$!> contains the operating system
		162	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		163	C<EPROTO>).
		164
		165	While not mandatory, it is I<highly> recommended to set this callback, as
		166	you will not be notified of errors otherwise. The default simply calls
		167	C<croak>.
		168
		169	=item on_read => $cb->($handle)
		170
		171	This sets the default read callback, which is called when data arrives
		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).
		175
		176	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		177	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		178	must not enlarge or modify the read buffer, you can only remove data at
		179	the beginning from it.
		180
		181	When an EOF condition is detected then AnyEvent::Handle will first try to
		182	feed all the remaining data to the queued callbacks and C<on_read> before
		183	calling the C<on_eof> callback. If no progress can be made, then a fatal
		184	error will be raised (with C<$!> set to C<EPIPE>).
		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
		207	=item on_drain => $cb->($handle)
		208
		209	This sets the callback that is called when the write buffer becomes empty
		210	(or when the callback is set and the buffer is empty already).
		211
		212	To append to the write buffer, use the C<< ->push_write >> method.
		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
		252	=item rbuf_max => <bytes>
		253
		254	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		255	when the read buffer ever (strictly) exceeds this size. This is useful to
		256	avoid some forms of denial-of-service attacks.
		257
		258	For example, a server accepting connections from untrusted sources should
		259	be configured to accept only so-and-so much data that it cannot act on
		260	(for example, when expecting a line, an attacker could send an unlimited
		261	amount of data without a callback ever being called as long as the line
		262	isn't finished).
		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
		290	=item read_size => <bytes>
		291
		292	The default read block size (the amount of bytes this module will
		293	try to read during each loop iteration, which affects memory
		294	requirements). Default: C<8192>.
		295
		296	=item low_water_mark => <bytes>
		297
		298	Sets the amount of bytes (default: C<0>) that make up an "empty" write
		299	buffer: If the write reaches this size or gets even samller it is
		300	considered empty.
		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
		417	=back
		418
		419	=cut
		420
		421	sub new {
		422	my $class = shift;
		423	my $self = bless { @_ }, $class;
		424
		425	if ($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 _rtw _wtw _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) = @_;
		488
		489	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
		490
		491	$self->{_activity} =
		492	$self->{_ractivity} =
		493	$self->{_wactivity} = AE::now;
		494
		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
		504	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
		505
		506	$self->start_read
		507	if $self->{on_read} || @{ $self->{_queue} };
		508
		509	$self->_drain_wbuf;
		510	}
		511
		512	sub _error {
		513	my ($self, $errno, $fatal, $message) = @_;
		514
		515	$! = $errno;
		516	$message ||= "$!";
		517
		518	if ($self->{on_error}) {
		519	$self->{on_error}($self, $fatal, $message);
		520	$self->destroy if $fatal;
		521	} elsif ($self->{fh}) {
		522	$self->destroy;
		523	Carp::croak "AnyEvent::Handle uncaught error: $message";
		524	}
		525	}
		526
		527	=item $fh = $handle->fh
		528
		529	This method returns the file handle used to create the L<AnyEvent::Handle> object.
		530
		531	=cut
		532
		533	sub fh { $_[0]{fh} }
		534
		535	=item $handle->on_error ($cb)
		536
		537	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
		538
		539	=cut
		540
		541	sub on_error {
		542	$_[0]{on_error} = $_[1];
		543	}
		544
		545	=item $handle->on_eof ($cb)
		546
		547	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
		548
		549	=cut
		550
		551	sub on_eof {
		552	$_[0]{on_eof} = $_[1];
		553	}
		554
		555	=item $handle->on_timeout ($cb)
		556
		557	=item $handle->on_rtimeout ($cb)
		558
		559	=item $handle->on_wtimeout ($cb)
		560
		561	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		562	callback, or disables the callback (but not the timeout) if C<$cb> =
		563	C<undef>. See the C<timeout> constructor argument and method.
		564
		565	=cut
		566
		567	# see below
		568
		569	=item $handle->autocork ($boolean)
		570
		571	Enables or disables the current autocork behaviour (see C<autocork>
		572	constructor argument). Changes will only take effect on the next write.
		573
		574	=cut
		575
		576	sub autocork {
		577	$_[0]{autocork} = $_[1];
		578	}
		579
		580	=item $handle->no_delay ($boolean)
		581
		582	Enables or disables the C<no_delay> setting (see constructor argument of
		583	the same name for details).
		584
		585	=cut
		586
		587	sub no_delay {
		588	$_[0]{no_delay} = $_[1];
		589
		590	eval {
		591	local $SIG{__DIE__};
		592	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]
		593	if $_[0]{fh};
		594	};
		595	}
		596
		597	=item $handle->on_starttls ($cb)
		598
		599	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		600
		601	=cut
		602
		603	sub on_starttls {
		604	$_[0]{on_starttls} = $_[1];
		605	}
		606
		607	=item $handle->on_stoptls ($cb)
		608
		609	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		610
		611	=cut
		612
		613	sub on_starttls {
		614	$_[0]{on_stoptls} = $_[1];
		615	}
		616
		617	=item $handle->rbuf_max ($max_octets)
		618
		619	Configures the C<rbuf_max> setting (C<undef> disables it).
		620
		621	=cut
		622
		623	sub rbuf_max {
		624	$_[0]{rbuf_max} = $_[1];
		625	}
		626
		627	#############################################################################
		628
		629	=item $handle->timeout ($seconds)
		630
		631	=item $handle->rtimeout ($seconds)
		632
		633	=item $handle->wtimeout ($seconds)
		634
		635	Configures (or disables) the inactivity timeout.
		636
		637	=item $handle->timeout_reset
		638
		639	=item $handle->rtimeout_reset
		640
		641	=item $handle->wtimeout_reset
		642
		643	Reset the activity timeout, as if data was received or sent.
		644
		645	These methods are cheap to call.
		646
		647	=cut
		648
		649	for my $dir ("", "r", "w") {
		650	my $timeout = "${dir}timeout";
		651	my $tw = "_${dir}tw";
		652	my $on_timeout = "on_${dir}timeout";
		653	my $activity = "_${dir}activity";
		654	my $cb;
		655
		656	*$on_timeout = sub {
		657	$_[0]{$on_timeout} = $_[1];
		658	};
		659
		660	*$timeout = sub {
		661	my ($self, $new_value) = @_;
		662
		663	$self->{$timeout} = $new_value;
		664	delete $self->{$tw}; &$cb;
		665	};
		666
		667	*{"${dir}timeout_reset"} = sub {
		668	$_[0]{$activity} = AE::now;
		669	};
		670
		671	# main workhorse:
		672	# reset the timeout watcher, as neccessary
		673	# also check for time-outs
		674	$cb = sub {
		675	my ($self) = @_;
		676
		677	if ($self->{$timeout} && $self->{fh}) {
		678	my $NOW = AE::now;
		679
		680	# when would the timeout trigger?
		681	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		682
		683	# now or in the past already?
		684	if ($after <= 0) {
		685	$self->{$activity} = $NOW;
		686
		687	if ($self->{$on_timeout}) {
		688	$self->{$on_timeout}($self);
		689	} else {
		690	$self->_error (Errno::ETIMEDOUT);
		691	}
		692
		693	# callback could have changed timeout value, optimise
		694	return unless $self->{$timeout};
		695
		696	# calculate new after
		697	$after = $self->{$timeout};
		698	}
		699
		700	Scalar::Util::weaken $self;
		701	return unless $self; # ->error could have destroyed $self
		702
		703	$self->{$tw} ||= AE::timer $after, 0, sub {
		704	delete $self->{$tw};
		705	$cb->($self);
36	chomp;	706	};
37	print "Line: $_";	707	} else {
		708	delete $self->{$tw};
		709	}
		710	}
		711	}
		712
		713	#############################################################################
		714
		715	=back
		716
		717	=head2 WRITE QUEUE
		718
		719	AnyEvent::Handle manages two queues per handle, one for writing and one
		720	for reading.
		721
		722	The write queue is very simple: you can add data to its end, and
		723	AnyEvent::Handle will automatically try to get rid of it for you.
		724
		725	When data could be written and the write buffer is shorter then the low
		726	water mark, the C<on_drain> callback will be invoked.
		727
		728	=over 4
		729
		730	=item $handle->on_drain ($cb)
		731
		732	Sets the C<on_drain> callback or clears it (see the description of
		733	C<on_drain> in the constructor).
		734
		735	=cut
		736
		737	sub on_drain {
		738	my ($self, $cb) = @_;
		739
		740	$self->{on_drain} = $cb;
		741
		742	$cb->($self)
		743	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
		744	}
		745
		746	=item $handle->push_write ($data)
		747
		748	Queues the given scalar to be written. You can push as much data as you
		749	want (only limited by the available memory), as C<AnyEvent::Handle>
		750	buffers it independently of the kernel.
		751
		752	=cut
		753
		754	sub _drain_wbuf {
		755	my ($self) = @_;
		756
		757	if (!$self->{_ww} && length $self->{wbuf}) {
		758
		759	Scalar::Util::weaken $self;
		760
		761	my $cb = sub {
		762	my $len = syswrite $self->{fh}, $self->{wbuf};
		763
		764	if (defined $len) {
		765	substr $self->{wbuf}, 0, $len, "";
		766
		767	$self->{_activity} = $self->{_wactivity} = AE::now;
		768
		769	$self->{on_drain}($self)
		770	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
		771	&& $self->{on_drain};
		772
		773	delete $self->{_ww} unless length $self->{wbuf};
		774	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		775	$self->_error ($!, 1);
		776	}
		777	};
		778
		779	# try to write data immediately
		780	$cb->() unless $self->{autocork};
		781
		782	# if still data left in wbuf, we need to poll
		783	$self->{_ww} = AE::io $self->{fh}, 1, $cb
		784	if length $self->{wbuf};
		785	};
		786	}
		787
		788	our %WH;
		789
		790	sub register_write_type($$) {
		791	$WH{$_[0]} = $_[1];
		792	}
		793
		794	sub push_write {
		795	my $self = shift;
		796
		797	if (@_ > 1) {
		798	my $type = shift;
		799
		800	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		801	->($self, @_);
		802	}
		803
		804	if ($self->{tls}) {
		805	$self->{_tls_wbuf} .= $_[0];
		806	&_dotls ($self) if $self->{fh};
		807	} else {
		808	$self->{wbuf} .= $_[0];
		809	$self->_drain_wbuf if $self->{fh};
		810	}
		811	}
		812
		813	=item $handle->push_write (type => @args)
		814
		815	Instead of formatting your data yourself, you can also let this module do
		816	the job by specifying a type and type-specific arguments.
		817
		818	Predefined types are (if you have ideas for additional types, feel free to
		819	drop by and tell us):
		820
		821	=over 4
		822
		823	=item netstring => $string
		824
		825	Formats the given value as netstring
		826	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		827
		828	=cut
		829
		830	register_write_type netstring => sub {
		831	my ($self, $string) = @_;
		832
		833	(length $string) . ":$string,"
		834	};
		835
		836	=item packstring => $format, $data
		837
		838	An octet string prefixed with an encoded length. The encoding C<$format>
		839	uses the same format as a Perl C<pack> format, but must specify a single
		840	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		841	optional C<!>, C<< < >> or C<< > >> modifier).
		842
		843	=cut
		844
		845	register_write_type packstring => sub {
		846	my ($self, $format, $string) = @_;
		847
		848	pack "$format/a*", $string
		849	};
		850
		851	=item json => $array_or_hashref
		852
		853	Encodes the given hash or array reference into a JSON object. Unless you
		854	provide your own JSON object, this means it will be encoded to JSON text
		855	in UTF-8.
		856
		857	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		858	one end of a handle and read them at the other end without using any
		859	additional framing.
		860
		861	The generated JSON text is guaranteed not to contain any newlines: While
		862	this module doesn't need delimiters after or between JSON texts to be
		863	able to read them, many other languages depend on that.
		864
		865	A simple RPC protocol that interoperates easily with others is to send
		866	JSON arrays (or objects, although arrays are usually the better choice as
		867	they mimic how function argument passing works) and a newline after each
		868	JSON text:
		869
		870	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		871	$handle->push_write ("\012");
		872
		873	An AnyEvent::Handle receiver would simply use the C<json> read type and
		874	rely on the fact that the newline will be skipped as leading whitespace:
		875
		876	$handle->push_read (json => sub { my $array = $_[1]; ... });
		877
		878	Other languages could read single lines terminated by a newline and pass
		879	this line into their JSON decoder of choice.
		880
		881	=cut
		882
		883	register_write_type json => sub {
		884	my ($self, $ref) = @_;
		885
		886	require JSON;
		887
		888	$self->{json} ? $self->{json}->encode ($ref)
		889	: JSON::encode_json ($ref)
		890	};
		891
		892	=item storable => $reference
		893
		894	Freezes the given reference using L<Storable> and writes it to the
		895	handle. Uses the C<nfreeze> format.
		896
		897	=cut
		898
		899	register_write_type storable => sub {
		900	my ($self, $ref) = @_;
		901
		902	require Storable;
		903
		904	pack "w/a*", Storable::nfreeze ($ref)
		905	};
		906
		907	=back
		908
		909	=item $handle->push_shutdown
		910
		911	Sometimes you know you want to close the socket after writing your data
		912	before it was actually written. One way to do that is to replace your
		913	C<on_drain> handler by a callback that shuts down the socket (and set
		914	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		915	replaces the C<on_drain> callback with:
		916
		917	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		918
		919	This simply shuts down the write side and signals an EOF condition to the
		920	the peer.
		921
		922	You can rely on the normal read queue and C<on_eof> handling
		923	afterwards. This is the cleanest way to close a connection.
		924
		925	=cut
		926
		927	sub push_shutdown {
		928	my ($self) = @_;
		929
		930	delete $self->{low_water_mark};
		931	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		932	}
		933
		934	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		935
		936	This function (not method) lets you add your own types to C<push_write>.
		937	Whenever the given C<type> is used, C<push_write> will invoke the code
		938	reference with the handle object and the remaining arguments.
		939
		940	The code reference is supposed to return a single octet string that will
		941	be appended to the write buffer.
		942
		943	Note that this is a function, and all types registered this way will be
		944	global, so try to use unique names.
		945
		946	=cut
		947
		948	#############################################################################
		949
		950	=back
		951
		952	=head2 READ QUEUE
		953
		954	AnyEvent::Handle manages two queues per handle, one for writing and one
		955	for reading.
		956
		957	The read queue is more complex than the write queue. It can be used in two
		958	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		959	a queue.
		960
		961	In the simple case, you just install an C<on_read> callback and whenever
		962	new data arrives, it will be called. You can then remove some data (if
		963	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
		964	leave the data there if you want to accumulate more (e.g. when only a
		965	partial message has been received so far).
		966
		967	In the more complex case, you want to queue multiple callbacks. In this
		968	case, AnyEvent::Handle will call the first queued callback each time new
		969	data arrives (also the first time it is queued) and removes it when it has
		970	done its job (see C<push_read>, below).
		971
		972	This way you can, for example, push three line-reads, followed by reading
		973	a chunk of data, and AnyEvent::Handle will execute them in order.
		974
		975	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		976	the specified number of bytes which give an XML datagram.
		977
		978	# in the default state, expect some header bytes
		979	$handle->on_read (sub {
		980	# some data is here, now queue the length-header-read (4 octets)
		981	shift->unshift_read (chunk => 4, sub {
		982	# header arrived, decode
		983	my $len = unpack "N", $_[1];
		984
		985	# now read the payload
		986	shift->unshift_read (chunk => $len, sub {
		987	my $xml = $_[1];
		988	# handle xml
		989	});
		990	});
		991	});
		992
		993	Example 2: Implement a client for a protocol that replies either with "OK"
		994	and another line or "ERROR" for the first request that is sent, and 64
		995	bytes for the second request. Due to the availability of a queue, we can
		996	just pipeline sending both requests and manipulate the queue as necessary
		997	in the callbacks.
		998
		999	When the first callback is called and sees an "OK" response, it will
		1000	C<unshift> another line-read. This line-read will be queued I<before> the
		1001	64-byte chunk callback.
		1002
		1003	# request one, returns either "OK + extra line" or "ERROR"
		1004	$handle->push_write ("request 1\015\012");
		1005
		1006	# we expect "ERROR" or "OK" as response, so push a line read
		1007	$handle->push_read (line => sub {
		1008	# if we got an "OK", we have to _prepend_ another line,
		1009	# so it will be read before the second request reads its 64 bytes
		1010	# which are already in the queue when this callback is called
		1011	# we don't do this in case we got an error
		1012	if ($_[1] eq "OK") {
		1013	$_[0]->unshift_read (line => sub {
		1014	my $response = $_[1];
		1015	...
		1016	});
38	}	1017	}
39	});	1018	});
40		1019
41	# or use the constructor to pass the callback:	1020	# request two, simply returns 64 octets
		1021	$handle->push_write ("request 2\015\012");
42		1022
43	my $ae_fh2 =	1023	# simply read 64 bytes, always
44	AnyEvent::Handle->new (	1024	$handle->push_read (chunk => 64, sub {
45	fh => \*STDIN,	1025	my $response = $_[1];
46	on_eof => sub {	1026	...
47	$cv->broadcast;	1027	});
48	},	1028
49	on_readline => sub {	1029	=over 4
50	my ($ae_fh, @lines) = @_;	1030
51	for (@lines) {	1031	=cut
52	chomp;	1032
53	print "Line: $_";	1033	sub _drain_rbuf {
		1034	my ($self) = @_;
		1035
		1036	# avoid recursion
		1037	return if $self->{_skip_drain_rbuf};
		1038	local $self->{_skip_drain_rbuf} = 1;
		1039
		1040	while () {
		1041	# we need to use a separate tls read buffer, as we must not receive data while
		1042	# we are draining the buffer, and this can only happen with TLS.
		1043	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1044	if exists $self->{_tls_rbuf};
		1045
		1046	my $len = length $self->{rbuf};
		1047
		1048	if (my $cb = shift @{ $self->{_queue} }) {
		1049	unless ($cb->($self)) {
		1050	# no progress can be made
		1051	# (not enough data and no data forthcoming)
		1052	$self->_error (Errno::EPIPE, 1), return
		1053	if $self->{_eof};
		1054
		1055	unshift @{ $self->{_queue} }, $cb;
54	}	1056	last;
55	}	1057	}
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}) {	1058	} elsif ($self->{on_read}) {
121	$self->readlines ($self->{on_readline});	1059	last unless $len;
122		1060
		1061	$self->{on_read}($self);
		1062
		1063	if (
		1064	$len == length $self->{rbuf} # if no data has been consumed
		1065	&& !@{ $self->{_queue} } # and the queue is still empty
		1066	&& $self->{on_read} # but we still have on_read
		1067	) {
		1068	# no further data will arrive
		1069	# so no progress can be made
		1070	$self->_error (Errno::EPIPE, 1), return
		1071	if $self->{_eof};
		1072
		1073	last; # more data might arrive
		1074	}
		1075	} else {
		1076	# read side becomes idle
		1077	delete $self->{_rw} unless $self->{tls};
		1078	last;
		1079	}
		1080	}
		1081
123	} elsif ($self->{on_eof}) {	1082	if ($self->{_eof}) {
124	$self->on_eof ($self->{on_eof});	1083	$self->{on_eof}
		1084	? $self->{on_eof}($self)
		1085	: $self->_error (0, 1, "Unexpected end-of-file");
125		1086
126	} elsif ($self->{on_error}) {	1087	return;
127	$self->on_eof ($self->{on_error});
128	}	1088	}
129		1089
130	return $self	1090	if (
131	}	1091	defined $self->{rbuf_max}
		1092	&& $self->{rbuf_max} < length $self->{rbuf}
		1093	) {
		1094	$self->_error (Errno::ENOSPC, 1), return;
		1095	}
132		1096
133	=item B<fh>	1097	# may need to restart read watcher
		1098	unless ($self->{_rw}) {
		1099	$self->start_read
		1100	if $self->{on_read} || @{ $self->{_queue} };
		1101	}
		1102	}
134		1103
135	This method returns the filehandle of the L<AnyEvent::Handle> object.	1104	=item $handle->on_read ($cb)
136		1105
137	=cut	1106	This replaces the currently set C<on_read> callback, or clears it (when
138		1107	the new callback is C<undef>). See the description of C<on_read> in the
139	sub fh { $_[0]->{fh} }	1108	constructor.
140
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		1109
149	=cut	1110	=cut
150		1111
151	sub on_read {	1112	sub on_read {
152	my ($self, $cb) = @_;	1113	my ($self, $cb) = @_;
		1114
153	$self->{on_read} = $cb;	1115	$self->{on_read} = $cb;
		1116	$self->_drain_rbuf if $cb;
		1117	}
154		1118
155	unless (defined $self->{on_read}) {	1119	=item $handle->rbuf
156	delete $self->{on_read_w};	1120
		1121	Returns the read buffer (as a modifiable lvalue).
		1122
		1123	You can access the read buffer directly as the C<< ->{rbuf} >>
		1124	member, if you want. However, the only operation allowed on the
		1125	read buffer (apart from looking at it) is removing data from its
		1126	beginning. Otherwise modifying or appending to it is not allowed and will
		1127	lead to hard-to-track-down bugs.
		1128
		1129	NOTE: The read buffer should only be used or modified if the C<on_read>,
		1130	C<push_read> or C<unshift_read> methods are used. The other read methods
		1131	automatically manage the read buffer.
		1132
		1133	=cut
		1134
		1135	sub rbuf : lvalue {
		1136	$_[0]{rbuf}
		1137	}
		1138
		1139	=item $handle->push_read ($cb)
		1140
		1141	=item $handle->unshift_read ($cb)
		1142
		1143	Append the given callback to the end of the queue (C<push_read>) or
		1144	prepend it (C<unshift_read>).
		1145
		1146	The callback is called each time some additional read data arrives.
		1147
		1148	It must check whether enough data is in the read buffer already.
		1149
		1150	If not enough data is available, it must return the empty list or a false
		1151	value, in which case it will be called repeatedly until enough data is
		1152	available (or an error condition is detected).
		1153
		1154	If enough data was available, then the callback must remove all data it is
		1155	interested in (which can be none at all) and return a true value. After returning
		1156	true, it will be removed from the queue.
		1157
		1158	=cut
		1159
		1160	our %RH;
		1161
		1162	sub register_read_type($$) {
		1163	$RH{$_[0]} = $_[1];
		1164	}
		1165
		1166	sub push_read {
		1167	my $self = shift;
		1168	my $cb = pop;
		1169
		1170	if (@_) {
		1171	my $type = shift;
		1172
		1173	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		1174	->($self, $cb, @_);
		1175	}
		1176
		1177	push @{ $self->{_queue} }, $cb;
		1178	$self->_drain_rbuf;
		1179	}
		1180
		1181	sub unshift_read {
		1182	my $self = shift;
		1183	my $cb = pop;
		1184
		1185	if (@_) {
		1186	my $type = shift;
		1187
		1188	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		1189	->($self, $cb, @_);
		1190	}
		1191
		1192
		1193	unshift @{ $self->{_queue} }, $cb;
		1194	$self->_drain_rbuf;
		1195	}
		1196
		1197	=item $handle->push_read (type => @args, $cb)
		1198
		1199	=item $handle->unshift_read (type => @args, $cb)
		1200
		1201	Instead of providing a callback that parses the data itself you can chose
		1202	between a number of predefined parsing formats, for chunks of data, lines
		1203	etc.
		1204
		1205	Predefined types are (if you have ideas for additional types, feel free to
		1206	drop by and tell us):
		1207
		1208	=over 4
		1209
		1210	=item chunk => $octets, $cb->($handle, $data)
		1211
		1212	Invoke the callback only once C<$octets> bytes have been read. Pass the
		1213	data read to the callback. The callback will never be called with less
		1214	data.
		1215
		1216	Example: read 2 bytes.
		1217
		1218	$handle->push_read (chunk => 2, sub {
		1219	warn "yay ", unpack "H*", $_[1];
		1220	});
		1221
		1222	=cut
		1223
		1224	register_read_type chunk => sub {
		1225	my ($self, $cb, $len) = @_;
		1226
		1227	sub {
		1228	$len <= length $_[0]{rbuf} or return;
		1229	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
		1230	1
		1231	}
		1232	};
		1233
		1234	=item line => [$eol, ]$cb->($handle, $line, $eol)
		1235
		1236	The callback will be called only once a full line (including the end of
		1237	line marker, C<$eol>) has been read. This line (excluding the end of line
		1238	marker) will be passed to the callback as second argument (C<$line>), and
		1239	the end of line marker as the third argument (C<$eol>).
		1240
		1241	The end of line marker, C<$eol>, can be either a string, in which case it
		1242	will be interpreted as a fixed record end marker, or it can be a regex
		1243	object (e.g. created by C<qr>), in which case it is interpreted as a
		1244	regular expression.
		1245
		1246	The end of line marker argument C<$eol> is optional, if it is missing (NOT
		1247	undef), then C<qr|\015?\012|> is used (which is good for most internet
		1248	protocols).
		1249
		1250	Partial lines at the end of the stream will never be returned, as they are
		1251	not marked by the end of line marker.
		1252
		1253	=cut
		1254
		1255	register_read_type line => sub {
		1256	my ($self, $cb, $eol) = @_;
		1257
		1258	if (@_ < 3) {
		1259	# this is more than twice as fast as the generic code below
		1260	sub {
		1261	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		1262
		1263	$cb->($_[0], $1, $2);
		1264	1
		1265	}
		1266	} else {
		1267	$eol = quotemeta $eol unless ref $eol;
		1268	$eol = qr|^(.*?)($eol)|s;
		1269
		1270	sub {
		1271	$_[0]{rbuf} =~ s/$eol// or return;
		1272
		1273	$cb->($_[0], $1, $2);
		1274	1
		1275	}
		1276	}
		1277	};
		1278
		1279	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1280
		1281	Makes a regex match against the regex object C<$accept> and returns
		1282	everything up to and including the match.
		1283
		1284	Example: read a single line terminated by '\n'.
		1285
		1286	$handle->push_read (regex => qr<\n>, sub { ... });
		1287
		1288	If C<$reject> is given and not undef, then it determines when the data is
		1289	to be rejected: it is matched against the data when the C<$accept> regex
		1290	does not match and generates an C<EBADMSG> error when it matches. This is
		1291	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1292	receive buffer overflow).
		1293
		1294	Example: expect a single decimal number followed by whitespace, reject
		1295	anything else (not the use of an anchor).
		1296
		1297	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1298
		1299	If C<$skip> is given and not C<undef>, then it will be matched against
		1300	the receive buffer when neither C<$accept> nor C<$reject> match,
		1301	and everything preceding and including the match will be accepted
		1302	unconditionally. This is useful to skip large amounts of data that you
		1303	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1304	have to start matching from the beginning. This is purely an optimisation
		1305	and is usually worth only when you expect more than a few kilobytes.
		1306
		1307	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1308	expect the header to be very large (it isn't in practise, but...), we use
		1309	a skip regex to skip initial portions. The skip regex is tricky in that
		1310	it only accepts something not ending in either \015 or \012, as these are
		1311	required for the accept regex.
		1312
		1313	$handle->push_read (regex =>
		1314	qr<\015\012\015\012>,
		1315	undef, # no reject
		1316	qr<^.*[^\015\012]>,
		1317	sub { ... });
		1318
		1319	=cut
		1320
		1321	register_read_type regex => sub {
		1322	my ($self, $cb, $accept, $reject, $skip) = @_;
		1323
		1324	my $data;
		1325	my $rbuf = \$self->{rbuf};
		1326
		1327	sub {
		1328	# accept
		1329	if ($$rbuf =~ $accept) {
		1330	$data .= substr $$rbuf, 0, $+[0], "";
		1331	$cb->($self, $data);
		1332	return 1;
		1333	}
		1334
		1335	# reject
		1336	if ($reject && $$rbuf =~ $reject) {
		1337	$self->_error (Errno::EBADMSG);
		1338	}
		1339
		1340	# skip
		1341	if ($skip && $$rbuf =~ $skip) {
		1342	$data .= substr $$rbuf, 0, $+[0], "";
		1343	}
		1344
		1345	()
		1346	}
		1347	};
		1348
		1349	=item netstring => $cb->($handle, $string)
		1350
		1351	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1352
		1353	Throws an error with C<$!> set to EBADMSG on format violations.
		1354
		1355	=cut
		1356
		1357	register_read_type netstring => sub {
		1358	my ($self, $cb) = @_;
		1359
		1360	sub {
		1361	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1362	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1363	$self->_error (Errno::EBADMSG);
		1364	}
157	return;	1365	return;
		1366	}
		1367
		1368	my $len = $1;
		1369
		1370	$self->unshift_read (chunk => $len, sub {
		1371	my $string = $_[1];
		1372	$_[0]->unshift_read (chunk => 1, sub {
		1373	if ($_[1] eq ",") {
		1374	$cb->($_[0], $string);
		1375	} else {
		1376	$self->_error (Errno::EBADMSG);
		1377	}
		1378	});
		1379	});
		1380
		1381	1
		1382	}
		1383	};
		1384
		1385	=item packstring => $format, $cb->($handle, $string)
		1386
		1387	An octet string prefixed with an encoded length. The encoding C<$format>
		1388	uses the same format as a Perl C<pack> format, but must specify a single
		1389	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1390	optional C<!>, C<< < >> or C<< > >> modifier).
		1391
		1392	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1393	EPP uses a prefix of C<N> (4 octtes).
		1394
		1395	Example: read a block of data prefixed by its length in BER-encoded
		1396	format (very efficient).
		1397
		1398	$handle->push_read (packstring => "w", sub {
		1399	my ($handle, $data) = @_;
158	}	1400	});
159		1401
160	$self->{on_read_w} =	1402	=cut
161	AnyEvent->io (poll => 'r', fh => $self->{fh}, cb => sub {	1403
162	#d# warn "READ:[$self->{read_size}] $self->{read_block_size} : ".length ($self->{rbuf})."\n";	1404	register_read_type packstring => sub {
		1405	my ($self, $cb, $format) = @_;
		1406
		1407	sub {
		1408	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1409	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1410	or return;
		1411
		1412	$format = length pack $format, $len;
		1413
		1414	# bypass unshift if we already have the remaining chunk
		1415	if ($format + $len <= length $_[0]{rbuf}) {
		1416	my $data = substr $_[0]{rbuf}, $format, $len;
		1417	substr $_[0]{rbuf}, 0, $format + $len, "";
		1418	$cb->($_[0], $data);
		1419	} else {
		1420	# remove prefix
		1421	substr $_[0]{rbuf}, 0, $format, "";
		1422
		1423	# read remaining chunk
		1424	$_[0]->unshift_read (chunk => $len, $cb);
		1425	}
		1426
		1427	1
		1428	}
		1429	};
		1430
		1431	=item json => $cb->($handle, $hash_or_arrayref)
		1432
		1433	Reads a JSON object or array, decodes it and passes it to the
		1434	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1435
		1436	If a C<json> object was passed to the constructor, then that will be used
		1437	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1438
		1439	This read type uses the incremental parser available with JSON version
		1440	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1441	dependency on your own: this module will load the JSON module, but
		1442	AnyEvent does not depend on it itself.
		1443
		1444	Since JSON texts are fully self-delimiting, the C<json> read and write
		1445	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1446	the C<json> write type description, above, for an actual example.
		1447
		1448	=cut
		1449
		1450	register_read_type json => sub {
		1451	my ($self, $cb) = @_;
		1452
		1453	my $json = $self->{json} ||=
		1454	eval { require JSON::XS; JSON::XS->new->utf8 }
		1455	|| do { require JSON; JSON->new->utf8 };
		1456
		1457	my $data;
163	my $rbuf_len = length $self->{rbuf};	1458	my $rbuf = \$self->{rbuf};
164	my $l;	1459
165	if (defined $self->{read_size}) {	1460	sub {
166	$l = sysread $self->{fh}, $self->{rbuf},	1461	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
167	($self->{read_size} - $rbuf_len), $rbuf_len;	1462
		1463	if ($ref) {
		1464	$self->{rbuf} = $json->incr_text;
		1465	$json->incr_text = "";
		1466	$cb->($self, $ref);
		1467
		1468	1
		1469	} elsif ($@) {
		1470	# error case
		1471	$json->incr_skip;
		1472
		1473	$self->{rbuf} = $json->incr_text;
		1474	$json->incr_text = "";
		1475
		1476	$self->_error (Errno::EBADMSG);
		1477
		1478	()
		1479	} else {
		1480	$self->{rbuf} = "";
		1481
		1482	()
		1483	}
		1484	}
		1485	};
		1486
		1487	=item storable => $cb->($handle, $ref)
		1488
		1489	Deserialises a L<Storable> frozen representation as written by the
		1490	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1491	data).
		1492
		1493	Raises C<EBADMSG> error if the data could not be decoded.
		1494
		1495	=cut
		1496
		1497	register_read_type storable => sub {
		1498	my ($self, $cb) = @_;
		1499
		1500	require Storable;
		1501
		1502	sub {
		1503	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1504	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1505	or return;
		1506
		1507	my $format = length pack "w", $len;
		1508
		1509	# bypass unshift if we already have the remaining chunk
		1510	if ($format + $len <= length $_[0]{rbuf}) {
		1511	my $data = substr $_[0]{rbuf}, $format, $len;
		1512	substr $_[0]{rbuf}, 0, $format + $len, "";
		1513	$cb->($_[0], Storable::thaw ($data));
		1514	} else {
		1515	# remove prefix
		1516	substr $_[0]{rbuf}, 0, $format, "";
		1517
		1518	# read remaining chunk
		1519	$_[0]->unshift_read (chunk => $len, sub {
		1520	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1521	$cb->($_[0], $ref);
		1522	} else {
		1523	$self->_error (Errno::EBADMSG);
		1524	}
		1525	});
		1526	}
		1527
		1528	1
		1529	}
		1530	};
		1531
		1532	=back
		1533
		1534	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1535
		1536	This function (not method) lets you add your own types to C<push_read>.
		1537
		1538	Whenever the given C<type> is used, C<push_read> will invoke the code
		1539	reference with the handle object, the callback and the remaining
		1540	arguments.
		1541
		1542	The code reference is supposed to return a callback (usually a closure)
		1543	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1544
		1545	It should invoke the passed callback when it is done reading (remember to
		1546	pass C<$handle> as first argument as all other callbacks do that).
		1547
		1548	Note that this is a function, and all types registered this way will be
		1549	global, so try to use unique names.
		1550
		1551	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1552	search for C<register_read_type>)).
		1553
		1554	=item $handle->stop_read
		1555
		1556	=item $handle->start_read
		1557
		1558	In rare cases you actually do not want to read anything from the
		1559	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
		1560	any queued callbacks will be executed then. To start reading again, call
		1561	C<start_read>.
		1562
		1563	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1564	you change the C<on_read> callback or push/unshift a read callback, and it
		1565	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1566	there are any read requests in the queue.
		1567
		1568	These methods will have no effect when in TLS mode (as TLS doesn't support
		1569	half-duplex connections).
		1570
		1571	=cut
		1572
		1573	sub stop_read {
		1574	my ($self) = @_;
		1575
		1576	delete $self->{_rw} unless $self->{tls};
		1577	}
		1578
		1579	sub start_read {
		1580	my ($self) = @_;
		1581
		1582	unless ($self->{_rw} || $self->{_eof}) {
		1583	Scalar::Util::weaken $self;
		1584
		1585	$self->{_rw} = AE::io $self->{fh}, 0, sub {
		1586	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
		1587	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
		1588
		1589	if ($len > 0) {
		1590	$self->{_activity} = $self->{_ractivity} = AE::now;
		1591
		1592	if ($self->{tls}) {
		1593	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1594
		1595	&_dotls ($self);
		1596	} else {
		1597	$self->_drain_rbuf;
		1598	}
		1599
		1600	} elsif (defined $len) {
		1601	delete $self->{_rw};
		1602	$self->{_eof} = 1;
		1603	$self->_drain_rbuf;
		1604
		1605	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		1606	return $self->_error ($!, 1);
		1607	}
		1608	};
		1609	}
		1610	}
		1611
		1612	our $ERROR_SYSCALL;
		1613	our $ERROR_WANT_READ;
		1614
		1615	sub _tls_error {
		1616	my ($self, $err) = @_;
		1617
		1618	return $self->_error ($!, 1)
		1619	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1620
		1621	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1622
		1623	# reduce error string to look less scary
		1624	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1625
		1626	if ($self->{_on_starttls}) {
		1627	(delete $self->{_on_starttls})->($self, undef, $err);
		1628	&_freetls;
		1629	} else {
		1630	&_freetls;
		1631	$self->_error (Errno::EPROTO, 1, $err);
		1632	}
		1633	}
		1634
		1635	# poll the write BIO and send the data if applicable
		1636	# also decode read data if possible
		1637	# this is basiclaly our TLS state machine
		1638	# more efficient implementations are possible with openssl,
		1639	# but not with the buggy and incomplete Net::SSLeay.
		1640	sub _dotls {
		1641	my ($self) = @_;
		1642
		1643	my $tmp;
		1644
		1645	if (length $self->{_tls_wbuf}) {
		1646	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		1647	substr $self->{_tls_wbuf}, 0, $tmp, "";
		1648	}
		1649
		1650	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1651	return $self->_tls_error ($tmp)
		1652	if $tmp != $ERROR_WANT_READ
		1653	&& ($tmp != $ERROR_SYSCALL || $!);
		1654	}
		1655
		1656	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1657	unless (length $tmp) {
		1658	$self->{_on_starttls}
		1659	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1660	&_freetls;
		1661
		1662	if ($self->{on_stoptls}) {
		1663	$self->{on_stoptls}($self);
		1664	return;
168	} else {	1665	} else {
169	$l = sysread $self->{fh}, $self->{rbuf}, $self->{read_block_size}, $rbuf_len;	1666	# 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};	1667	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];	1668	$self->{_eof} = 1;
316	}	1669	}
317	}	1670	}
318	return;	1671
		1672	$self->{_tls_rbuf} .= $tmp;
		1673	$self->_drain_rbuf;
		1674	$self->{tls} or return; # tls session might have gone away in callback
		1675	}
		1676
		1677	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1678	return $self->_tls_error ($tmp)
		1679	if $tmp != $ERROR_WANT_READ
		1680	&& ($tmp != $ERROR_SYSCALL || $!);
		1681
		1682	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1683	$self->{wbuf} .= $tmp;
		1684	$self->_drain_wbuf;
		1685	}
		1686
		1687	$self->{_on_starttls}
		1688	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
		1689	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
		1690	}
		1691
		1692	=item $handle->starttls ($tls[, $tls_ctx])
		1693
		1694	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1695	object is created, you can also do that at a later time by calling
		1696	C<starttls>.
		1697
		1698	Starting TLS is currently an asynchronous operation - when you push some
		1699	write data and then call C<< ->starttls >> then TLS negotiation will start
		1700	immediately, after which the queued write data is then sent.
		1701
		1702	The first argument is the same as the C<tls> constructor argument (either
		1703	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1704
		1705	The second argument is the optional C<AnyEvent::TLS> object that is used
		1706	when AnyEvent::Handle has to create its own TLS connection object, or
		1707	a hash reference with C<< key => value >> pairs that will be used to
		1708	construct a new context.
		1709
		1710	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
		1711	context in C<< $handle->{tls_ctx} >> after this call and can be used or
		1712	changed to your liking. Note that the handshake might have already started
		1713	when this function returns.
		1714
		1715	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1716	handshakes on the same stream. Best do not attempt to use the stream after
		1717	stopping TLS.
		1718
		1719	=cut
		1720
		1721	our %TLS_CACHE; #TODO not yet documented, should we?
		1722
		1723	sub starttls {
		1724	my ($self, $tls, $ctx) = @_;
		1725
		1726	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1727	if $self->{tls};
		1728
		1729	$self->{tls} = $tls;
		1730	$self->{tls_ctx} = $ctx if @_ > 2;
		1731
		1732	return unless $self->{fh};
		1733
		1734	require Net::SSLeay;
		1735
		1736	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
		1737	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
		1738
		1739	$tls = $self->{tls};
		1740	$ctx = $self->{tls_ctx};
		1741
		1742	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
		1743
		1744	if ("HASH" eq ref $ctx) {
		1745	require AnyEvent::TLS;
		1746
		1747	if ($ctx->{cache}) {
		1748	my $key = $ctx+0;
		1749	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1750	} else {
		1751	$ctx = new AnyEvent::TLS %$ctx;
		1752	}
		1753	}
319	}	1754
		1755	$self->{tls_ctx} = $ctx || TLS_CTX ();
		1756	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
320		1757
321	my $wba = shift @{$self->{write_bufs}}	1758	# basically, this is deep magic (because SSL_read should have the same issues)
322	or return;	1759	# but the openssl maintainers basically said: "trust us, it just works".
		1760	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1761	# and mismaintained ssleay-module doesn't even offer them).
		1762	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1763	#
		1764	# in short: this is a mess.
		1765	#
		1766	# note that we do not try to keep the length constant between writes as we are required to do.
		1767	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1768	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1769	# have identity issues in that area.
		1770	# Net::SSLeay::CTX_set_mode ($ssl,
		1771	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1772	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1773	Net::SSLeay::CTX_set_mode ($tls, 1|2);
323		1774
324	unless (defined $wba->[0]) {	1775	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
325	$wba->[1]->($self) if $wba->[1];	1776	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
326	$self->_check_writer;	1777
327	return;	1778	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		1779
		1780	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
		1781
		1782	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
		1783	if $self->{on_starttls};
		1784
		1785	&_dotls; # need to trigger the initial handshake
		1786	$self->start_read; # make sure we actually do read
		1787	}
		1788
		1789	=item $handle->stoptls
		1790
		1791	Shuts down the SSL connection - this makes a proper EOF handshake by
		1792	sending a close notify to the other side, but since OpenSSL doesn't
		1793	support non-blocking shut downs, it is not guarenteed that you can re-use
		1794	the stream afterwards.
		1795
		1796	=cut
		1797
		1798	sub stoptls {
		1799	my ($self) = @_;
		1800
		1801	if ($self->{tls}) {
		1802	Net::SSLeay::shutdown ($self->{tls});
		1803
		1804	&_dotls;
		1805
		1806	# # we don't give a shit. no, we do, but we can't. no...#d#
		1807	# # we, we... have to use openssl :/#d#
		1808	# &_freetls;#d#
		1809	}
		1810	}
		1811
		1812	sub _freetls {
		1813	my ($self) = @_;
		1814
		1815	return unless $self->{tls};
		1816
		1817	$self->{tls_ctx}->_put_session (delete $self->{tls})
		1818	if $self->{tls} > 0;
328	}	1819
		1820	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		1821	}
329		1822
330	$self->{wbuf} = $wba->[0];	1823	sub DESTROY {
331	$self->{write_cb} = $wba->[1];	1824	my ($self) = @_;
332		1825
333	$self->{write_w} =	1826	&_freetls;
334	AnyEvent->io (poll => 'w', fh => $self->{fh}, cb => sub {	1827
		1828	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1829
		1830	if ($linger && length $self->{wbuf} && $self->{fh}) {
		1831	my $fh = delete $self->{fh};
		1832	my $wbuf = delete $self->{wbuf};
		1833
		1834	my @linger;
		1835
		1836	push @linger, AE::io $fh, 1, sub {
335	my $l = syswrite $self->{fh}, $self->{wbuf}, length $self->{wbuf};	1837	my $len = syswrite $fh, $wbuf, length $wbuf;
336		1838
337	if (not defined $l) {	1839	if ($len > 0) {
338	return if $! == EAGAIN || $! == EINTR;	1840	substr $wbuf, 0, $len, "";
339	delete $self->{write_w};
340	$self->{on_error}->($self) if $self->{on_error};
341
342	} else {	1841	} else {
343	substr $self->{wbuf}, 0, $l, '';	1842	@linger = (); # end
344
345	if (length ($self->{wbuf}) == 0) {
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	}	1843	}
355	});	1844	};
		1845	push @linger, AE::timer $linger, 0, sub {
		1846	@linger = ();
		1847	};
		1848	}
		1849	}
		1850
		1851	=item $handle->destroy
		1852
		1853	Shuts down the handle object as much as possible - this call ensures that
		1854	no further callbacks will be invoked and as many resources as possible
		1855	will be freed. Any method you will call on the handle object after
		1856	destroying it in this way will be silently ignored (and it will return the
		1857	empty list).
		1858
		1859	Normally, you can just "forget" any references to an AnyEvent::Handle
		1860	object and it will simply shut down. This works in fatal error and EOF
		1861	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1862	callback, so when you want to destroy the AnyEvent::Handle object from
		1863	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1864	that case.
		1865
		1866	Destroying the handle object in this way has the advantage that callbacks
		1867	will be removed as well, so if those are the only reference holders (as
		1868	is common), then one doesn't need to do anything special to break any
		1869	reference cycles.
		1870
		1871	The handle might still linger in the background and write out remaining
		1872	data, as specified by the C<linger> option, however.
		1873
		1874	=cut
		1875
		1876	sub destroy {
		1877	my ($self) = @_;
		1878
		1879	$self->DESTROY;
		1880	%$self = ();
		1881	bless $self, "AnyEvent::Handle::destroyed";
		1882	}
		1883
		1884	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		1885	#nop
		1886	}
		1887
		1888	=item AnyEvent::Handle::TLS_CTX
		1889
		1890	This function creates and returns the AnyEvent::TLS object used by default
		1891	for TLS mode.
		1892
		1893	The context is created by calling L<AnyEvent::TLS> without any arguments.
		1894
		1895	=cut
		1896
		1897	our $TLS_CTX;
		1898
		1899	sub TLS_CTX() {
		1900	$TLS_CTX ||= do {
		1901	require AnyEvent::TLS;
		1902
		1903	new AnyEvent::TLS
		1904	}
356	}	1905	}
357		1906
358	=back	1907	=back
359		1908
		1909
		1910	=head1 NONFREQUENTLY ASKED QUESTIONS
		1911
		1912	=over 4
		1913
		1914	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1915	still get further invocations!
		1916
		1917	That's because AnyEvent::Handle keeps a reference to itself when handling
		1918	read or write callbacks.
		1919
		1920	It is only safe to "forget" the reference inside EOF or error callbacks,
		1921	from within all other callbacks, you need to explicitly call the C<<
		1922	->destroy >> method.
		1923
		1924	=item I get different callback invocations in TLS mode/Why can't I pause
		1925	reading?
		1926
		1927	Unlike, say, TCP, TLS connections do not consist of two independent
		1928	communication channels, one for each direction. Or put differently. The
		1929	read and write directions are not independent of each other: you cannot
		1930	write data unless you are also prepared to read, and vice versa.
		1931
		1932	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1933	callback invocations when you are not expecting any read data - the reason
		1934	is that AnyEvent::Handle always reads in TLS mode.
		1935
		1936	During the connection, you have to make sure that you always have a
		1937	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1938	connection (or when you no longer want to use it) you can call the
		1939	C<destroy> method.
		1940
		1941	=item How do I read data until the other side closes the connection?
		1942
		1943	If you just want to read your data into a perl scalar, the easiest way
		1944	to achieve this is by setting an C<on_read> callback that does nothing,
		1945	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1946	will be in C<$_[0]{rbuf}>:
		1947
		1948	$handle->on_read (sub { });
		1949	$handle->on_eof (undef);
		1950	$handle->on_error (sub {
		1951	my $data = delete $_[0]{rbuf};
		1952	});
		1953
		1954	The reason to use C<on_error> is that TCP connections, due to latencies
		1955	and packets loss, might get closed quite violently with an error, when in
		1956	fact, all data has been received.
		1957
		1958	It is usually better to use acknowledgements when transferring data,
		1959	to make sure the other side hasn't just died and you got the data
		1960	intact. This is also one reason why so many internet protocols have an
		1961	explicit QUIT command.
		1962
		1963	=item I don't want to destroy the handle too early - how do I wait until
		1964	all data has been written?
		1965
		1966	After writing your last bits of data, set the C<on_drain> callback
		1967	and destroy the handle in there - with the default setting of
		1968	C<low_water_mark> this will be called precisely when all data has been
		1969	written to the socket:
		1970
		1971	$handle->push_write (...);
		1972	$handle->on_drain (sub {
		1973	warn "all data submitted to the kernel\n";
		1974	undef $handle;
		1975	});
		1976
		1977	If you just want to queue some data and then signal EOF to the other side,
		1978	consider using C<< ->push_shutdown >> instead.
		1979
		1980	=item I want to contact a TLS/SSL server, I don't care about security.
		1981
		1982	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		1983	simply connect to it and then create the AnyEvent::Handle with the C<tls>
		1984	parameter:
		1985
		1986	tcp_connect $host, $port, sub {
		1987	my ($fh) = @_;
		1988
		1989	my $handle = new AnyEvent::Handle
		1990	fh => $fh,
		1991	tls => "connect",
		1992	on_error => sub { ... };
		1993
		1994	$handle->push_write (...);
		1995	};
		1996
		1997	=item I want to contact a TLS/SSL server, I do care about security.
		1998
		1999	Then you should additionally enable certificate verification, including
		2000	peername verification, if the protocol you use supports it (see
		2001	L<AnyEvent::TLS>, C<verify_peername>).
		2002
		2003	E.g. for HTTPS:
		2004
		2005	tcp_connect $host, $port, sub {
		2006	my ($fh) = @_;
		2007
		2008	my $handle = new AnyEvent::Handle
		2009	fh => $fh,
		2010	peername => $host,
		2011	tls => "connect",
		2012	tls_ctx => { verify => 1, verify_peername => "https" },
		2013	...
		2014
		2015	Note that you must specify the hostname you connected to (or whatever
		2016	"peername" the protocol needs) as the C<peername> argument, otherwise no
		2017	peername verification will be done.
		2018
		2019	The above will use the system-dependent default set of trusted CA
		2020	certificates. If you want to check against a specific CA, add the
		2021	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
		2022
		2023	tls_ctx => {
		2024	verify => 1,
		2025	verify_peername => "https",
		2026	ca_file => "my-ca-cert.pem",
		2027	},
		2028
		2029	=item I want to create a TLS/SSL server, how do I do that?
		2030
		2031	Well, you first need to get a server certificate and key. You have
		2032	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2033	self-signed certificate (cheap. check the search engine of your choice,
		2034	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2035	nice program for that purpose).
		2036
		2037	Then create a file with your private key (in PEM format, see
		2038	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
		2039	file should then look like this:
		2040
		2041	-----BEGIN RSA PRIVATE KEY-----
		2042	...header data
		2043	... lots of base64'y-stuff
		2044	-----END RSA PRIVATE KEY-----
		2045
		2046	-----BEGIN CERTIFICATE-----
		2047	... lots of base64'y-stuff
		2048	-----END CERTIFICATE-----
		2049
		2050	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2051	specify this file as C<cert_file>:
		2052
		2053	tcp_server undef, $port, sub {
		2054	my ($fh) = @_;
		2055
		2056	my $handle = new AnyEvent::Handle
		2057	fh => $fh,
		2058	tls => "accept",
		2059	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2060	...
		2061
		2062	When you have intermediate CA certificates that your clients might not
		2063	know about, just append them to the C<cert_file>.
		2064
		2065	=back
		2066
		2067
		2068	=head1 SUBCLASSING AnyEvent::Handle
		2069
		2070	In many cases, you might want to subclass AnyEvent::Handle.
		2071
		2072	To make this easier, a given version of AnyEvent::Handle uses these
		2073	conventions:
		2074
		2075	=over 4
		2076
		2077	=item * all constructor arguments become object members.
		2078
		2079	At least initially, when you pass a C<tls>-argument to the constructor it
		2080	will end up in C<< $handle->{tls} >>. Those members might be changed or
		2081	mutated later on (for example C<tls> will hold the TLS connection object).
		2082
		2083	=item * other object member names are prefixed with an C<_>.
		2084
		2085	All object members not explicitly documented (internal use) are prefixed
		2086	with an underscore character, so the remaining non-C<_>-namespace is free
		2087	for use for subclasses.
		2088
		2089	=item * all members not documented here and not prefixed with an underscore
		2090	are free to use in subclasses.
		2091
		2092	Of course, new versions of AnyEvent::Handle may introduce more "public"
		2093	member variables, but thats just life, at least it is documented.
		2094
		2095	=back
		2096
360	=head1 AUTHOR	2097	=head1 AUTHOR
361		2098
362	Robin Redeker, C<< <elmex at ta-sa.org> >>	2099	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
363
364	=head1 BUGS
365
366	Please report any bugs or feature requests to
367	C<bug-io-anyevent at rt.cpan.org>, or through the web interface at
368	L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=IO-AnyEvent>.
369	I will be notified, and then you'll automatically be notified of progress on
370	your bug as I make changes.
371
372	=head1 SUPPORT
373
374	You can find documentation for this module with the perldoc command.
375
376	perldoc AnyEvent::Handle
377
378	You can also look for information at:
379
380	=over 4
381
382	=item * AnnoCPAN: Annotated CPAN documentation
383
384	L<http://annocpan.org/dist/IO-AnyEvent>
385
386	=item * CPAN Ratings
387
388	L<http://cpanratings.perl.org/d/IO-AnyEvent>
389
390	=item * RT: CPAN's request tracker
391
392	L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=IO-AnyEvent>
393
394	=item * Search CPAN
395
396	L<http://search.cpan.org/dist/IO-AnyEvent>
397
398	=back
399
400	=head1 ACKNOWLEDGEMENTS
401
402	=head1 COPYRIGHT & LICENSE
403
404	Copyright 2008 Robin Redeker, all rights reserved.
405
406	This program is free software; you can redistribute it and/or modify it
407	under the same terms as Perl itself.
408		2100
409	=cut	2101	=cut
410		2102
411	1; # End of AnyEvent::Handle	2103	1; # End of AnyEvent::Handle

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