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Revision 1.4 by elmex, Sun Apr 27 20:20:20 2008 UTC vs.
Revision 1.72 by root, Wed Jul 16 21:17:59 2008 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	use warnings;	3	no warnings;
4	use strict;	4	use strict;
5		5
6	use AnyEvent;	6	use AnyEvent ();
7	use IO::Handle;	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		8	use Scalar::Util ();
		9	use Carp ();
		10	use Fcntl ();
8	use Errno qw/EAGAIN EINTR/;	11	use Errno qw(EAGAIN EINTR);
9		12
10	=head1 NAME	13	=head1 NAME
11		14
12	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
13		16
14	=head1 VERSION
15
16	Version 0.01
17
18	=cut	17	=cut
19		18
20	our $VERSION = '0.01';	19	our $VERSION = 4.21;
21		20
22	=head1 SYNOPSIS	21	=head1 SYNOPSIS
23		22
24	use AnyEvent;	23	use AnyEvent;
25	use AnyEvent::Handle;	24	use AnyEvent::Handle;
26		25
27	my $cv = AnyEvent->condvar;	26	my $cv = AnyEvent->condvar;
28		27
29	my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	28	my $handle =
30
31	$ae_fh->on_eof (sub { $cv->broadcast });
32
33	$ae_fh->readlines (sub {
34	my ($ae_fh, @lines) = @_;
35	for (@lines) {
36	chomp;
37	print "Line: $_";
38	}
39	});
40
41	# or use the constructor to pass the callback:
42
43	my $ae_fh2 =
44	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
45	fh => \*STDIN,	30	fh => \*STDIN,
46	on_eof => sub {	31	on_eof => sub {
47	$cv->broadcast;	32	$cv->broadcast;
48	},	33	},
		34	);
		35
		36	# send some request line
		37	$handle->push_write ("getinfo\015\012");
		38
		39	# read the response line
		40	$handle->push_read (line => sub {
		41	my ($handle, $line) = @_;
		42	warn "read line <$line>\n";
		43	$cv->send;
		44	});
		45
		46	$cv->recv;
		47
		48	=head1 DESCRIPTION
		49
		50	This module is a helper module to make it easier to do event-based I/O on
		51	filehandles. For utility functions for doing non-blocking connects and accepts
		52	on sockets see L<AnyEvent::Util>.
		53
		54	In the following, when the documentation refers to of "bytes" then this
		55	means characters. As sysread and syswrite are used for all I/O, their
		56	treatment of characters applies to this module as well.
		57
		58	All callbacks will be invoked with the handle object as their first
		59	argument.
		60
		61	=head1 METHODS
		62
		63	=over 4
		64
		65	=item B<new (%args)>
		66
		67	The constructor supports these arguments (all as key => value pairs).
		68
		69	=over 4
		70
		71	=item fh => $filehandle [MANDATORY]
		72
		73	The filehandle this L<AnyEvent::Handle> object will operate on.
		74
		75	NOTE: The filehandle will be set to non-blocking (using
		76	AnyEvent::Util::fh_nonblocking).
		77
		78	=item on_eof => $cb->($handle)
		79
		80	Set the callback to be called when an end-of-file condition is detcted,
		81	i.e. in the case of a socket, when the other side has closed the
		82	connection cleanly.
		83
		84	While not mandatory, it is highly recommended to set an eof callback,
		85	otherwise you might end up with a closed socket while you are still
		86	waiting for data.
		87
		88	=item on_error => $cb->($handle, $fatal)
		89
		90	This is the error callback, which is called when, well, some error
		91	occured, such as not being able to resolve the hostname, failure to
		92	connect or a read error.
		93
		94	Some errors are fatal (which is indicated by C<$fatal> being true). On
		95	fatal errors the handle object will be shut down and will not be
		96	usable. Non-fatal errors can be retried by simply returning, but it is
		97	recommended to simply ignore this parameter and instead abondon the handle
		98	object when this callback is invoked.
		99
		100	On callback entrance, the value of C<$!> contains the operating system
		101	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
		102
		103	While not mandatory, it is I<highly> recommended to set this callback, as
		104	you will not be notified of errors otherwise. The default simply calls
		105	C<croak>.
		106
		107	=item on_read => $cb->($handle)
		108
		109	This sets the default read callback, which is called when data arrives
		110	and no read request is in the queue (unlike read queue callbacks, this
		111	callback will only be called when at least one octet of data is in the
		112	read buffer).
		113
		114	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		115	method or access the C<$handle->{rbuf}> member directly.
		116
		117	When an EOF condition is detected then AnyEvent::Handle will first try to
		118	feed all the remaining data to the queued callbacks and C<on_read> before
		119	calling the C<on_eof> callback. If no progress can be made, then a fatal
		120	error will be raised (with C<$!> set to C<EPIPE>).
		121
		122	=item on_drain => $cb->($handle)
		123
		124	This sets the callback that is called when the write buffer becomes empty
		125	(or when the callback is set and the buffer is empty already).
		126
		127	To append to the write buffer, use the C<< ->push_write >> method.
		128
		129	This callback is useful when you don't want to put all of your write data
		130	into the queue at once, for example, when you want to write the contents
		131	of some file to the socket you might not want to read the whole file into
		132	memory and push it into the queue, but instead only read more data from
		133	the file when the write queue becomes empty.
		134
		135	=item timeout => $fractional_seconds
		136
		137	If non-zero, then this enables an "inactivity" timeout: whenever this many
		138	seconds pass without a successful read or write on the underlying file
		139	handle, the C<on_timeout> callback will be invoked (and if that one is
		140	missing, an C<ETIMEDOUT> error will be raised).
		141
		142	Note that timeout processing is also active when you currently do not have
		143	any outstanding read or write requests: If you plan to keep the connection
		144	idle then you should disable the timout temporarily or ignore the timeout
		145	in the C<on_timeout> callback.
		146
		147	Zero (the default) disables this timeout.
		148
		149	=item on_timeout => $cb->($handle)
		150
		151	Called whenever the inactivity timeout passes. If you return from this
		152	callback, then the timeout will be reset as if some activity had happened,
		153	so this condition is not fatal in any way.
		154
		155	=item rbuf_max => <bytes>
		156
		157	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		158	when the read buffer ever (strictly) exceeds this size. This is useful to
		159	avoid denial-of-service attacks.
		160
		161	For example, a server accepting connections from untrusted sources should
		162	be configured to accept only so-and-so much data that it cannot act on
		163	(for example, when expecting a line, an attacker could send an unlimited
		164	amount of data without a callback ever being called as long as the line
		165	isn't finished).
		166
		167	=item autocork => <boolean>
		168
		169	When disabled (the default), then C<push_write> will try to immediately
		170	write the data to the handle if possible. This avoids having to register
		171	a write watcher and wait for the next event loop iteration, but can be
		172	inefficient if you write multiple small chunks (this disadvantage is
		173	usually avoided by your kernel's nagle algorithm, see C<low_delay>).
		174
		175	When enabled, then writes will always be queued till the next event loop
		176	iteration. This is efficient when you do many small writes per iteration,
		177	but less efficient when you do a single write only.
		178
		179	=item no_delay => <boolean>
		180
		181	When doing small writes on sockets, your operating system kernel might
		182	wait a bit for more data before actually sending it out. This is called
		183	the Nagle algorithm, and usually it is beneficial.
		184
		185	In some situations you want as low a delay as possible, which cna be
		186	accomplishd by setting this option to true.
		187
		188	The default is your opertaing system's default behaviour, this option
		189	explicitly enables or disables it, if possible.
		190
		191	=item read_size => <bytes>
		192
		193	The default read block size (the amount of bytes this module will try to read
		194	during each (loop iteration). Default: C<8192>.
		195
		196	=item low_water_mark => <bytes>
		197
		198	Sets the amount of bytes (default: C<0>) that make up an "empty" write
		199	buffer: If the write reaches this size or gets even samller it is
		200	considered empty.
		201
		202	=item linger => <seconds>
		203
		204	If non-zero (default: C<3600>), then the destructor of the
		205	AnyEvent::Handle object will check wether there is still outstanding write
		206	data and will install a watcher that will write out this data. No errors
		207	will be reported (this mostly matches how the operating system treats
		208	outstanding data at socket close time).
		209
		210	This will not work for partial TLS data that could not yet been
		211	encoded. This data will be lost.
		212
		213	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
		214
		215	When this parameter is given, it enables TLS (SSL) mode, that means it
		216	will start making tls handshake and will transparently encrypt/decrypt
		217	data.
		218
		219	TLS mode requires Net::SSLeay to be installed (it will be loaded
		220	automatically when you try to create a TLS handle).
		221
		222	For the TLS server side, use C<accept>, and for the TLS client side of a
		223	connection, use C<connect> mode.
		224
		225	You can also provide your own TLS connection object, but you have
		226	to make sure that you call either C<Net::SSLeay::set_connect_state>
		227	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		228	AnyEvent::Handle.
		229
		230	See the C<starttls> method if you need to start TLs negotiation later.
		231
		232	=item tls_ctx => $ssl_ctx
		233
		234	Use the given Net::SSLeay::CTX object to create the new TLS connection
		235	(unless a connection object was specified directly). If this parameter is
		236	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		237
		238	=item json => JSON or JSON::XS object
		239
		240	This is the json coder object used by the C<json> read and write types.
		241
		242	If you don't supply it, then AnyEvent::Handle will create and use a
		243	suitable one, which will write and expect UTF-8 encoded JSON texts.
		244
		245	Note that you are responsible to depend on the JSON module if you want to
		246	use this functionality, as AnyEvent does not have a dependency itself.
		247
		248	=item filter_r => $cb
		249
		250	=item filter_w => $cb
		251
		252	These exist, but are undocumented at this time.
		253
		254	=back
		255
		256	=cut
		257
		258	sub new {
		259	my $class = shift;
		260
		261	my $self = bless { @_ }, $class;
		262
		263	$self->{fh} or Carp::croak "mandatory argument fh is missing";
		264
		265	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
		266
		267	if ($self->{tls}) {
		268	require Net::SSLeay;
		269	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
		270	}
		271
		272	$self->{_activity} = AnyEvent->now;
		273	$self->_timeout;
		274
		275	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
		276	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
		277
		278	$self->start_read
		279	if $self->{on_read};
		280
		281	$self
		282	}
		283
		284	sub _shutdown {
		285	my ($self) = @_;
		286
		287	delete $self->{_tw};
		288	delete $self->{_rw};
		289	delete $self->{_ww};
		290	delete $self->{fh};
		291
		292	$self->stoptls;
		293	}
		294
		295	sub _error {
		296	my ($self, $errno, $fatal) = @_;
		297
		298	$self->_shutdown
		299	if $fatal;
		300
		301	$! = $errno;
		302
		303	if ($self->{on_error}) {
		304	$self->{on_error}($self, $fatal);
		305	} else {
		306	Carp::croak "AnyEvent::Handle uncaught error: $!";
		307	}
		308	}
		309
		310	=item $fh = $handle->fh
		311
		312	This method returns the file handle of the L<AnyEvent::Handle> object.
		313
		314	=cut
		315
		316	sub fh { $_[0]{fh} }
		317
		318	=item $handle->on_error ($cb)
		319
		320	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
		321
		322	=cut
		323
		324	sub on_error {
		325	$_[0]{on_error} = $_[1];
		326	}
		327
		328	=item $handle->on_eof ($cb)
		329
		330	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
		331
		332	=cut
		333
		334	sub on_eof {
		335	$_[0]{on_eof} = $_[1];
		336	}
		337
		338	=item $handle->on_timeout ($cb)
		339
		340	Replace the current C<on_timeout> callback, or disables the callback
		341	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
		342	argument.
		343
		344	=cut
		345
		346	sub on_timeout {
		347	$_[0]{on_timeout} = $_[1];
		348	}
		349
		350	=item $handle->autocork ($boolean)
		351
		352	Enables or disables the current autocork behaviour (see C<autocork>
		353	constructor argument).
		354
		355	=cut
		356
		357	=item $handle->no_delay ($boolean)
		358
		359	Enables or disables the C<no_delay> setting (see constructor argument of
		360	the same name for details).
		361
		362	=cut
		363
		364	sub no_delay {
		365	$_[0]{no_delay} = $_[1];
		366
		367	eval {
		368	local $SIG{__DIE__};
		369	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		370	};
		371	}
		372
		373	#############################################################################
		374
		375	=item $handle->timeout ($seconds)
		376
		377	Configures (or disables) the inactivity timeout.
		378
		379	=cut
		380
		381	sub timeout {
		382	my ($self, $timeout) = @_;
		383
		384	$self->{timeout} = $timeout;
		385	$self->_timeout;
		386	}
		387
		388	# reset the timeout watcher, as neccessary
		389	# also check for time-outs
		390	sub _timeout {
		391	my ($self) = @_;
		392
		393	if ($self->{timeout}) {
		394	my $NOW = AnyEvent->now;
		395
		396	# when would the timeout trigger?
		397	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		398
		399	# now or in the past already?
		400	if ($after <= 0) {
		401	$self->{_activity} = $NOW;
		402
		403	if ($self->{on_timeout}) {
		404	$self->{on_timeout}($self);
		405	} else {
		406	$self->_error (&Errno::ETIMEDOUT);
		407	}
		408
		409	# callback could have changed timeout value, optimise
		410	return unless $self->{timeout};
		411
		412	# calculate new after
		413	$after = $self->{timeout};
		414	}
		415
		416	Scalar::Util::weaken $self;
		417	return unless $self; # ->error could have destroyed $self
		418
		419	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		420	delete $self->{_tw};
		421	$self->_timeout;
		422	});
		423	} else {
		424	delete $self->{_tw};
		425	}
		426	}
		427
		428	#############################################################################
		429
		430	=back
		431
		432	=head2 WRITE QUEUE
		433
		434	AnyEvent::Handle manages two queues per handle, one for writing and one
		435	for reading.
		436
		437	The write queue is very simple: you can add data to its end, and
		438	AnyEvent::Handle will automatically try to get rid of it for you.
		439
		440	When data could be written and the write buffer is shorter then the low
		441	water mark, the C<on_drain> callback will be invoked.
		442
		443	=over 4
		444
		445	=item $handle->on_drain ($cb)
		446
		447	Sets the C<on_drain> callback or clears it (see the description of
		448	C<on_drain> in the constructor).
		449
		450	=cut
		451
		452	sub on_drain {
		453	my ($self, $cb) = @_;
		454
		455	$self->{on_drain} = $cb;
		456
		457	$cb->($self)
		458	if $cb && $self->{low_water_mark} >= length $self->{wbuf};
		459	}
		460
		461	=item $handle->push_write ($data)
		462
		463	Queues the given scalar to be written. You can push as much data as you
		464	want (only limited by the available memory), as C<AnyEvent::Handle>
		465	buffers it independently of the kernel.
		466
		467	=cut
		468
		469	sub _drain_wbuf {
		470	my ($self) = @_;
		471
		472	if (!$self->{_ww} && length $self->{wbuf}) {
		473
		474	Scalar::Util::weaken $self;
		475
		476	my $cb = sub {
		477	my $len = syswrite $self->{fh}, $self->{wbuf};
		478
		479	if ($len >= 0) {
		480	substr $self->{wbuf}, 0, $len, "";
		481
		482	$self->{_activity} = AnyEvent->now;
		483
		484	$self->{on_drain}($self)
		485	if $self->{low_water_mark} >= length $self->{wbuf}
		486	&& $self->{on_drain};
		487
		488	delete $self->{_ww} unless length $self->{wbuf};
		489	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		490	$self->_error ($!, 1);
		491	}
		492	};
		493
		494	# try to write data immediately
		495	$cb->() unless $self->{autocork};
		496
		497	# if still data left in wbuf, we need to poll
		498	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
		499	if length $self->{wbuf};
		500	};
		501	}
		502
		503	our %WH;
		504
		505	sub register_write_type($$) {
		506	$WH{$_[0]} = $_[1];
		507	}
		508
		509	sub push_write {
		510	my $self = shift;
		511
		512	if (@_ > 1) {
		513	my $type = shift;
		514
		515	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		516	->($self, @_);
		517	}
		518
		519	if ($self->{filter_w}) {
		520	$self->{filter_w}($self, \$_[0]);
		521	} else {
		522	$self->{wbuf} .= $_[0];
		523	$self->_drain_wbuf;
		524	}
		525	}
		526
		527	=item $handle->push_write (type => @args)
		528
		529	Instead of formatting your data yourself, you can also let this module do
		530	the job by specifying a type and type-specific arguments.
		531
		532	Predefined types are (if you have ideas for additional types, feel free to
		533	drop by and tell us):
		534
		535	=over 4
		536
		537	=item netstring => $string
		538
		539	Formats the given value as netstring
		540	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		541
		542	=cut
		543
		544	register_write_type netstring => sub {
		545	my ($self, $string) = @_;
		546
		547	sprintf "%d:%s,", (length $string), $string
		548	};
		549
		550	=item packstring => $format, $data
		551
		552	An octet string prefixed with an encoded length. The encoding C<$format>
		553	uses the same format as a Perl C<pack> format, but must specify a single
		554	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		555	optional C<!>, C<< < >> or C<< > >> modifier).
		556
		557	=cut
		558
		559	register_write_type packstring => sub {
		560	my ($self, $format, $string) = @_;
		561
		562	pack "$format/a*", $string
		563	};
		564
		565	=item json => $array_or_hashref
		566
		567	Encodes the given hash or array reference into a JSON object. Unless you
		568	provide your own JSON object, this means it will be encoded to JSON text
		569	in UTF-8.
		570
		571	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		572	one end of a handle and read them at the other end without using any
		573	additional framing.
		574
		575	The generated JSON text is guaranteed not to contain any newlines: While
		576	this module doesn't need delimiters after or between JSON texts to be
		577	able to read them, many other languages depend on that.
		578
		579	A simple RPC protocol that interoperates easily with others is to send
		580	JSON arrays (or objects, although arrays are usually the better choice as
		581	they mimic how function argument passing works) and a newline after each
		582	JSON text:
		583
		584	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		585	$handle->push_write ("\012");
		586
		587	An AnyEvent::Handle receiver would simply use the C<json> read type and
		588	rely on the fact that the newline will be skipped as leading whitespace:
		589
		590	$handle->push_read (json => sub { my $array = $_[1]; ... });
		591
		592	Other languages could read single lines terminated by a newline and pass
		593	this line into their JSON decoder of choice.
		594
		595	=cut
		596
		597	register_write_type json => sub {
		598	my ($self, $ref) = @_;
		599
		600	require JSON;
		601
		602	$self->{json} ? $self->{json}->encode ($ref)
		603	: JSON::encode_json ($ref)
		604	};
		605
		606	=item storable => $reference
		607
		608	Freezes the given reference using L<Storable> and writes it to the
		609	handle. Uses the C<nfreeze> format.
		610
		611	=cut
		612
		613	register_write_type storable => sub {
		614	my ($self, $ref) = @_;
		615
		616	require Storable;
		617
		618	pack "w/a*", Storable::nfreeze ($ref)
		619	};
		620
		621	=back
		622
		623	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		624
		625	This function (not method) lets you add your own types to C<push_write>.
		626	Whenever the given C<type> is used, C<push_write> will invoke the code
		627	reference with the handle object and the remaining arguments.
		628
		629	The code reference is supposed to return a single octet string that will
		630	be appended to the write buffer.
		631
		632	Note that this is a function, and all types registered this way will be
		633	global, so try to use unique names.
		634
		635	=cut
		636
		637	#############################################################################
		638
		639	=back
		640
		641	=head2 READ QUEUE
		642
		643	AnyEvent::Handle manages two queues per handle, one for writing and one
		644	for reading.
		645
		646	The read queue is more complex than the write queue. It can be used in two
		647	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		648	a queue.
		649
		650	In the simple case, you just install an C<on_read> callback and whenever
		651	new data arrives, it will be called. You can then remove some data (if
		652	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
		653	leave the data there if you want to accumulate more (e.g. when only a
		654	partial message has been received so far).
		655
		656	In the more complex case, you want to queue multiple callbacks. In this
		657	case, AnyEvent::Handle will call the first queued callback each time new
		658	data arrives (also the first time it is queued) and removes it when it has
		659	done its job (see C<push_read>, below).
		660
		661	This way you can, for example, push three line-reads, followed by reading
		662	a chunk of data, and AnyEvent::Handle will execute them in order.
		663
		664	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		665	the specified number of bytes which give an XML datagram.
		666
		667	# in the default state, expect some header bytes
		668	$handle->on_read (sub {
		669	# some data is here, now queue the length-header-read (4 octets)
		670	shift->unshift_read (chunk => 4, sub {
		671	# header arrived, decode
		672	my $len = unpack "N", $_[1];
		673
		674	# now read the payload
		675	shift->unshift_read (chunk => $len, sub {
		676	my $xml = $_[1];
		677	# handle xml
		678	});
		679	});
		680	});
		681
		682	Example 2: Implement a client for a protocol that replies either with "OK"
		683	and another line or "ERROR" for the first request that is sent, and 64
		684	bytes for the second request. Due to the availability of a queue, we can
		685	just pipeline sending both requests and manipulate the queue as necessary
		686	in the callbacks.
		687
		688	When the first callback is called and sees an "OK" response, it will
		689	C<unshift> another line-read. This line-read will be queued I<before> the
		690	64-byte chunk callback.
		691
		692	# request one, returns either "OK + extra line" or "ERROR"
		693	$handle->push_write ("request 1\015\012");
		694
		695	# we expect "ERROR" or "OK" as response, so push a line read
		696	$handle->push_read (line => sub {
		697	# if we got an "OK", we have to _prepend_ another line,
		698	# so it will be read before the second request reads its 64 bytes
		699	# which are already in the queue when this callback is called
		700	# we don't do this in case we got an error
		701	if ($_[1] eq "OK") {
49	on_readline => sub {	702	$_[0]->unshift_read (line => sub {
50	my ($ae_fh, @lines) = @_;	703	my $response = $_[1];
51	for (@lines) {	704	...
52	chomp;	705	});
53	print "Line: $_";	706	}
		707	});
		708
		709	# request two, simply returns 64 octets
		710	$handle->push_write ("request 2\015\012");
		711
		712	# simply read 64 bytes, always
		713	$handle->push_read (chunk => 64, sub {
		714	my $response = $_[1];
		715	...
		716	});
		717
		718	=over 4
		719
		720	=cut
		721
		722	sub _drain_rbuf {
		723	my ($self) = @_;
		724
		725	local $self->{_in_drain} = 1;
		726
		727	if (
		728	defined $self->{rbuf_max}
		729	&& $self->{rbuf_max} < length $self->{rbuf}
		730	) {
		731	return $self->_error (&Errno::ENOSPC, 1);
		732	}
		733
		734	while () {
		735	no strict 'refs';
		736
		737	my $len = length $self->{rbuf};
		738
		739	if (my $cb = shift @{ $self->{_queue} }) {
		740	unless ($cb->($self)) {
		741	if ($self->{_eof}) {
		742	# no progress can be made (not enough data and no data forthcoming)
		743	$self->_error (&Errno::EPIPE, 1), last;
54	}	744	}
		745
		746	unshift @{ $self->{_queue} }, $cb;
		747	last;
55	}	748	}
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}) {	749	} elsif ($self->{on_read}) {
121	$self->readlines ($self->{on_readline});	750	last unless $len;
122		751
123	} elsif ($self->{on_eof}) {	752	$self->{on_read}($self);
		753
		754	if (
		755	$len == length $self->{rbuf} # if no data has been consumed
		756	&& !@{ $self->{_queue} } # and the queue is still empty
		757	&& $self->{on_read} # but we still have on_read
		758	) {
		759	# no further data will arrive
		760	# so no progress can be made
		761	$self->_error (&Errno::EPIPE, 1), last
		762	if $self->{_eof};
		763
		764	last; # more data might arrive
		765	}
		766	} else {
		767	# read side becomes idle
		768	delete $self->{_rw};
		769	last;
		770	}
		771	}
		772
		773	$self->{on_eof}($self)
124	$self->on_eof ($self->{on_eof});	774	if $self->{_eof} && $self->{on_eof};
125		775
126	} elsif ($self->{on_error}) {	776	# may need to restart read watcher
127	$self->on_eof ($self->{on_error});	777	unless ($self->{_rw}) {
		778	$self->start_read
		779	if $self->{on_read} || @{ $self->{_queue} };
128	}	780	}
129
130	return $self
131	}	781	}
132		782
133	=item B<fh>	783	=item $handle->on_read ($cb)
134		784
135	This method returns the filehandle of the L<AnyEvent::Handle> object.	785	This replaces the currently set C<on_read> callback, or clears it (when
136		786	the new callback is C<undef>). See the description of C<on_read> in the
137	=cut	787	constructor.
138
139	sub fh { $_[0]->{fh} }
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		788
149	=cut	789	=cut
150		790
151	sub on_read {	791	sub on_read {
152	my ($self, $cb) = @_;	792	my ($self, $cb) = @_;
		793
153	$self->{on_read} = $cb;	794	$self->{on_read} = $cb;
		795	$self->_drain_rbuf if $cb && !$self->{_in_drain};
		796	}
154		797
155	unless (defined $self->{on_read}) {	798	=item $handle->rbuf
156	delete $self->{on_read_w};	799
		800	Returns the read buffer (as a modifiable lvalue).
		801
		802	You can access the read buffer directly as the C<< ->{rbuf} >> member, if
		803	you want.
		804
		805	NOTE: The read buffer should only be used or modified if the C<on_read>,
		806	C<push_read> or C<unshift_read> methods are used. The other read methods
		807	automatically manage the read buffer.
		808
		809	=cut
		810
		811	sub rbuf : lvalue {
		812	$_[0]{rbuf}
		813	}
		814
		815	=item $handle->push_read ($cb)
		816
		817	=item $handle->unshift_read ($cb)
		818
		819	Append the given callback to the end of the queue (C<push_read>) or
		820	prepend it (C<unshift_read>).
		821
		822	The callback is called each time some additional read data arrives.
		823
		824	It must check whether enough data is in the read buffer already.
		825
		826	If not enough data is available, it must return the empty list or a false
		827	value, in which case it will be called repeatedly until enough data is
		828	available (or an error condition is detected).
		829
		830	If enough data was available, then the callback must remove all data it is
		831	interested in (which can be none at all) and return a true value. After returning
		832	true, it will be removed from the queue.
		833
		834	=cut
		835
		836	our %RH;
		837
		838	sub register_read_type($$) {
		839	$RH{$_[0]} = $_[1];
		840	}
		841
		842	sub push_read {
		843	my $self = shift;
		844	my $cb = pop;
		845
		846	if (@_) {
		847	my $type = shift;
		848
		849	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		850	->($self, $cb, @_);
		851	}
		852
		853	push @{ $self->{_queue} }, $cb;
		854	$self->_drain_rbuf unless $self->{_in_drain};
		855	}
		856
		857	sub unshift_read {
		858	my $self = shift;
		859	my $cb = pop;
		860
		861	if (@_) {
		862	my $type = shift;
		863
		864	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		865	->($self, $cb, @_);
		866	}
		867
		868
		869	unshift @{ $self->{_queue} }, $cb;
		870	$self->_drain_rbuf unless $self->{_in_drain};
		871	}
		872
		873	=item $handle->push_read (type => @args, $cb)
		874
		875	=item $handle->unshift_read (type => @args, $cb)
		876
		877	Instead of providing a callback that parses the data itself you can chose
		878	between a number of predefined parsing formats, for chunks of data, lines
		879	etc.
		880
		881	Predefined types are (if you have ideas for additional types, feel free to
		882	drop by and tell us):
		883
		884	=over 4
		885
		886	=item chunk => $octets, $cb->($handle, $data)
		887
		888	Invoke the callback only once C<$octets> bytes have been read. Pass the
		889	data read to the callback. The callback will never be called with less
		890	data.
		891
		892	Example: read 2 bytes.
		893
		894	$handle->push_read (chunk => 2, sub {
		895	warn "yay ", unpack "H*", $_[1];
		896	});
		897
		898	=cut
		899
		900	register_read_type chunk => sub {
		901	my ($self, $cb, $len) = @_;
		902
		903	sub {
		904	$len <= length $_[0]{rbuf} or return;
		905	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
		906	1
		907	}
		908	};
		909
		910	# compatibility with older API
		911	sub push_read_chunk {
		912	$_[0]->push_read (chunk => $_[1], $_[2]);
		913	}
		914
		915	sub unshift_read_chunk {
		916	$_[0]->unshift_read (chunk => $_[1], $_[2]);
		917	}
		918
		919	=item line => [$eol, ]$cb->($handle, $line, $eol)
		920
		921	The callback will be called only once a full line (including the end of
		922	line marker, C<$eol>) has been read. This line (excluding the end of line
		923	marker) will be passed to the callback as second argument (C<$line>), and
		924	the end of line marker as the third argument (C<$eol>).
		925
		926	The end of line marker, C<$eol>, can be either a string, in which case it
		927	will be interpreted as a fixed record end marker, or it can be a regex
		928	object (e.g. created by C<qr>), in which case it is interpreted as a
		929	regular expression.
		930
		931	The end of line marker argument C<$eol> is optional, if it is missing (NOT
		932	undef), then C<qr|\015?\012|> is used (which is good for most internet
		933	protocols).
		934
		935	Partial lines at the end of the stream will never be returned, as they are
		936	not marked by the end of line marker.
		937
		938	=cut
		939
		940	register_read_type line => sub {
		941	my ($self, $cb, $eol) = @_;
		942
		943	$eol = qr|(\015?\012)| if @_ < 3;
		944	$eol = quotemeta $eol unless ref $eol;
		945	$eol = qr|^(.*?)($eol)|s;
		946
		947	sub {
		948	$_[0]{rbuf} =~ s/$eol// or return;
		949
		950	$cb->($_[0], $1, $2);
		951	1
		952	}
		953	};
		954
		955	# compatibility with older API
		956	sub push_read_line {
		957	my $self = shift;
		958	$self->push_read (line => @_);
		959	}
		960
		961	sub unshift_read_line {
		962	my $self = shift;
		963	$self->unshift_read (line => @_);
		964	}
		965
		966	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		967
		968	Makes a regex match against the regex object C<$accept> and returns
		969	everything up to and including the match.
		970
		971	Example: read a single line terminated by '\n'.
		972
		973	$handle->push_read (regex => qr<\n>, sub { ... });
		974
		975	If C<$reject> is given and not undef, then it determines when the data is
		976	to be rejected: it is matched against the data when the C<$accept> regex
		977	does not match and generates an C<EBADMSG> error when it matches. This is
		978	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		979	receive buffer overflow).
		980
		981	Example: expect a single decimal number followed by whitespace, reject
		982	anything else (not the use of an anchor).
		983
		984	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		985
		986	If C<$skip> is given and not C<undef>, then it will be matched against
		987	the receive buffer when neither C<$accept> nor C<$reject> match,
		988	and everything preceding and including the match will be accepted
		989	unconditionally. This is useful to skip large amounts of data that you
		990	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		991	have to start matching from the beginning. This is purely an optimisation
		992	and is usually worth only when you expect more than a few kilobytes.
		993
		994	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		995	expect the header to be very large (it isn't in practise, but...), we use
		996	a skip regex to skip initial portions. The skip regex is tricky in that
		997	it only accepts something not ending in either \015 or \012, as these are
		998	required for the accept regex.
		999
		1000	$handle->push_read (regex =>
		1001	qr<\015\012\015\012>,
		1002	undef, # no reject
		1003	qr<^.*[^\015\012]>,
		1004	sub { ... });
		1005
		1006	=cut
		1007
		1008	register_read_type regex => sub {
		1009	my ($self, $cb, $accept, $reject, $skip) = @_;
		1010
		1011	my $data;
		1012	my $rbuf = \$self->{rbuf};
		1013
		1014	sub {
		1015	# accept
		1016	if ($$rbuf =~ $accept) {
		1017	$data .= substr $$rbuf, 0, $+[0], "";
		1018	$cb->($self, $data);
		1019	return 1;
		1020	}
		1021
		1022	# reject
		1023	if ($reject && $$rbuf =~ $reject) {
		1024	$self->_error (&Errno::EBADMSG);
		1025	}
		1026
		1027	# skip
		1028	if ($skip && $$rbuf =~ $skip) {
		1029	$data .= substr $$rbuf, 0, $+[0], "";
		1030	}
		1031
		1032	()
		1033	}
		1034	};
		1035
		1036	=item netstring => $cb->($handle, $string)
		1037
		1038	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1039
		1040	Throws an error with C<$!> set to EBADMSG on format violations.
		1041
		1042	=cut
		1043
		1044	register_read_type netstring => sub {
		1045	my ($self, $cb) = @_;
		1046
		1047	sub {
		1048	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1049	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1050	$self->_error (&Errno::EBADMSG);
		1051	}
157	return;	1052	return;
		1053	}
		1054
		1055	my $len = $1;
		1056
		1057	$self->unshift_read (chunk => $len, sub {
		1058	my $string = $_[1];
		1059	$_[0]->unshift_read (chunk => 1, sub {
		1060	if ($_[1] eq ",") {
		1061	$cb->($_[0], $string);
		1062	} else {
		1063	$self->_error (&Errno::EBADMSG);
		1064	}
		1065	});
		1066	});
		1067
		1068	1
		1069	}
		1070	};
		1071
		1072	=item packstring => $format, $cb->($handle, $string)
		1073
		1074	An octet string prefixed with an encoded length. The encoding C<$format>
		1075	uses the same format as a Perl C<pack> format, but must specify a single
		1076	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1077	optional C<!>, C<< < >> or C<< > >> modifier).
		1078
		1079	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.
		1080
		1081	Example: read a block of data prefixed by its length in BER-encoded
		1082	format (very efficient).
		1083
		1084	$handle->push_read (packstring => "w", sub {
		1085	my ($handle, $data) = @_;
158	}	1086	});
159		1087
160	$self->{on_read_w} =	1088	=cut
161	AnyEvent->io (poll => 'r', fh => $self->{fh}, cb => sub {	1089
162	#d# warn "READ:[$self->{read_size}] $self->{read_block_size} : ".length ($self->{rbuf})."\n";	1090	register_read_type packstring => sub {
		1091	my ($self, $cb, $format) = @_;
		1092
		1093	sub {
		1094	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1095	defined (my $len = eval { unpack $format, $_[0]->{rbuf} })
		1096	or return;
		1097
		1098	# remove prefix
		1099	substr $_[0]->{rbuf}, 0, (length pack $format, $len), "";
		1100
		1101	# read rest
		1102	$_[0]->unshift_read (chunk => $len, $cb);
		1103
		1104	1
		1105	}
		1106	};
		1107
		1108	=item json => $cb->($handle, $hash_or_arrayref)
		1109
		1110	Reads a JSON object or array, decodes it and passes it to the callback.
		1111
		1112	If a C<json> object was passed to the constructor, then that will be used
		1113	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1114
		1115	This read type uses the incremental parser available with JSON version
		1116	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1117	dependency on your own: this module will load the JSON module, but
		1118	AnyEvent does not depend on it itself.
		1119
		1120	Since JSON texts are fully self-delimiting, the C<json> read and write
		1121	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1122	the C<json> write type description, above, for an actual example.
		1123
		1124	=cut
		1125
		1126	register_read_type json => sub {
		1127	my ($self, $cb) = @_;
		1128
		1129	require JSON;
		1130
		1131	my $data;
163	my $rbuf_len = length $self->{rbuf};	1132	my $rbuf = \$self->{rbuf};
164	my $l;	1133
165	if (defined $self->{read_size}) {	1134	my $json = $self->{json} ||= JSON->new->utf8;
166	$l = sysread $self->{fh}, $self->{rbuf},	1135
167	($self->{read_size} - $rbuf_len), $rbuf_len;	1136	sub {
		1137	my $ref = $json->incr_parse ($self->{rbuf});
		1138
		1139	if ($ref) {
		1140	$self->{rbuf} = $json->incr_text;
		1141	$json->incr_text = "";
		1142	$cb->($self, $ref);
		1143
		1144	1
		1145	} else {
		1146	$self->{rbuf} = "";
		1147	()
		1148	}
		1149	}
		1150	};
		1151
		1152	=item storable => $cb->($handle, $ref)
		1153
		1154	Deserialises a L<Storable> frozen representation as written by the
		1155	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1156	data).
		1157
		1158	Raises C<EBADMSG> error if the data could not be decoded.
		1159
		1160	=cut
		1161
		1162	register_read_type storable => sub {
		1163	my ($self, $cb) = @_;
		1164
		1165	require Storable;
		1166
		1167	sub {
		1168	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1169	defined (my $len = eval { unpack "w", $_[0]->{rbuf} })
		1170	or return;
		1171
		1172	# remove prefix
		1173	substr $_[0]->{rbuf}, 0, (length pack "w", $len), "";
		1174
		1175	# read rest
		1176	$_[0]->unshift_read (chunk => $len, sub {
		1177	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1178	$cb->($_[0], $ref);
168	} else {	1179	} else {
169	$l = sysread $self->{fh}, $self->{rbuf}, $self->{read_block_size}, $rbuf_len;	1180	$self->_error (&Errno::EBADMSG);
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};
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	}	1181	}
185	});	1182	});
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	});	1183	}
254	}	1184	};
255		1185
256	=item B<readlines ($callback)>	1186	=back
257		1187
258	=item B<readlines ($sep, $callback)>	1188	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
259		1189
260	This method will read lines from the filehandle, seperated by C<$sep> or C<"\n">	1190	This function (not method) lets you add your own types to C<push_read>.
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		1191
264	The C<$callback> will be called when at least one	1192	Whenever the given C<type> is used, C<push_read> will invoke the code
265	line could be read. The first argument to the C<$callback> will be the L<AnyEvent::Handle>	1193	reference with the handle object, the callback and the remaining
266	object itself and the rest of the arguments will be the read lines.	1194	arguments.
267		1195
268	NOTE: This method will override any callbacks installed via the C<on_read> method.	1196	The code reference is supposed to return a callback (usually a closure)
		1197	that works as a plain read callback (see C<< ->push_read ($cb) >>).
269		1198
270	=cut	1199	It should invoke the passed callback when it is done reading (remember to
		1200	pass C<$handle> as first argument as all other callbacks do that).
271		1201
272	sub readlines {	1202	Note that this is a function, and all types registered this way will be
273	my ($self, $NL, $cb) = @_;	1203	global, so try to use unique names.
274		1204
275	if (ref $NL) {	1205	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
276	$cb = $NL;	1206	search for C<register_read_type>)).
277	$NL = "\n";
278	}
279		1207
280	$self->{on_readline} = $cb;	1208	=item $handle->stop_read
281		1209
282	$self->on_read (sub {	1210	=item $handle->start_read
283	my @lines;
284	push @lines, $1 while $_[0]->{rbuf} =~ s/(.*)$NL//;
285	$self->{on_readline}->($_[0], @lines);
286	});
287	}
288		1211
289	=item B<write ($data)>	1212	In rare cases you actually do not want to read anything from the
		1213	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
		1214	any queued callbacks will be executed then. To start reading again, call
		1215	C<start_read>.
290		1216
291	=item B<write ($callback)>	1217	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1218	you change the C<on_read> callback or push/unshift a read callback, and it
		1219	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1220	there are any read requests in the queue.
292		1221
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	1222	=cut
300		1223
301	sub write {	1224	sub stop_read {
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) = @_;	1225	my ($self) = @_;
310		1226
311	if ($self->{write_w}) {	1227	delete $self->{_rw};
312	unless ($self->{write_cb}) {	1228	}
313	while (@{$self->{write_bufs}} && not defined $self->{write_bufs}->[0]->[1]) {
314	my $wba = shift @{$self->{write_bufs}};
315	$self->{wbuf} .= $wba->[0];
316	}
317	}
318	return;
319	}
320		1229
321	my $wba = shift @{$self->{write_bufs}}	1230	sub start_read {
322	or return;	1231	my ($self) = @_;
323		1232
324	unless (defined $wba->[0]) {	1233	unless ($self->{_rw} || $self->{_eof}) {
325	$wba->[1]->($self) if $wba->[1];	1234	Scalar::Util::weaken $self;
326	$self->_check_writer;
327	return;
328	}
329		1235
330	$self->{wbuf} = $wba->[0];	1236	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
331	$self->{write_cb} = $wba->[1];	1237	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
		1238	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
332		1239
333	$self->{write_w} =	1240	if ($len > 0) {
334	AnyEvent->io (poll => 'w', fh => $self->{fh}, cb => sub {	1241	$self->{_activity} = AnyEvent->now;
335	my $l = syswrite $self->{fh}, $self->{wbuf}, length $self->{wbuf};
336		1242
		1243	$self->{filter_r}
		1244	? $self->{filter_r}($self, $rbuf)
		1245	: $self->{_in_drain} || $self->_drain_rbuf;
		1246
337	if (not defined $l) {	1247	} elsif (defined $len) {
338	return if $! == EAGAIN || $! == EINTR;
339	delete $self->{write_w};	1248	delete $self->{_rw};
340	$self->{on_error}->($self) if $self->{on_error};	1249	$self->{_eof} = 1;
		1250	$self->_drain_rbuf unless $self->{_in_drain};
341		1251
342	} else {	1252	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
343	substr $self->{wbuf}, 0, $l, '';	1253	return $self->_error ($!, 1);
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	$self->_check_writer;
353	}
354	}	1254	}
355	});	1255	});
		1256	}
		1257	}
		1258
		1259	sub _dotls {
		1260	my ($self) = @_;
		1261
		1262	my $buf;
		1263
		1264	if (length $self->{_tls_wbuf}) {
		1265	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		1266	substr $self->{_tls_wbuf}, 0, $len, "";
		1267	}
		1268	}
		1269
		1270	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1271	$self->{wbuf} .= $buf;
		1272	$self->_drain_wbuf;
		1273	}
		1274
		1275	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
		1276	if (length $buf) {
		1277	$self->{rbuf} .= $buf;
		1278	$self->_drain_rbuf unless $self->{_in_drain};
		1279	} else {
		1280	# let's treat SSL-eof as we treat normal EOF
		1281	$self->{_eof} = 1;
		1282	$self->_shutdown;
		1283	return;
		1284	}
		1285	}
		1286
		1287	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1288
		1289	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1290	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1291	return $self->_error ($!, 1);
		1292	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1293	return $self->_error (&Errno::EIO, 1);
		1294	}
		1295
		1296	# all others are fine for our purposes
		1297	}
		1298	}
		1299
		1300	=item $handle->starttls ($tls[, $tls_ctx])
		1301
		1302	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1303	object is created, you can also do that at a later time by calling
		1304	C<starttls>.
		1305
		1306	The first argument is the same as the C<tls> constructor argument (either
		1307	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1308
		1309	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1310	used when AnyEvent::Handle has to create its own TLS connection object.
		1311
		1312	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1313	call and can be used or changed to your liking. Note that the handshake
		1314	might have already started when this function returns.
		1315
		1316	=cut
		1317
		1318	sub starttls {
		1319	my ($self, $ssl, $ctx) = @_;
		1320
		1321	$self->stoptls;
		1322
		1323	if ($ssl eq "accept") {
		1324	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1325	Net::SSLeay::set_accept_state ($ssl);
		1326	} elsif ($ssl eq "connect") {
		1327	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1328	Net::SSLeay::set_connect_state ($ssl);
		1329	}
		1330
		1331	$self->{tls} = $ssl;
		1332
		1333	# basically, this is deep magic (because SSL_read should have the same issues)
		1334	# but the openssl maintainers basically said: "trust us, it just works".
		1335	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1336	# and mismaintained ssleay-module doesn't even offer them).
		1337	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1338	Net::SSLeay::CTX_set_mode ($self->{tls},
		1339	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1340	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1341
		1342	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1343	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1344
		1345	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1346
		1347	$self->{filter_w} = sub {
		1348	$_[0]{_tls_wbuf} .= ${$_[1]};
		1349	&_dotls;
		1350	};
		1351	$self->{filter_r} = sub {
		1352	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
		1353	&_dotls;
		1354	};
		1355	}
		1356
		1357	=item $handle->stoptls
		1358
		1359	Destroys the SSL connection, if any. Partial read or write data will be
		1360	lost.
		1361
		1362	=cut
		1363
		1364	sub stoptls {
		1365	my ($self) = @_;
		1366
		1367	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};
		1368
		1369	delete $self->{_rbio};
		1370	delete $self->{_wbio};
		1371	delete $self->{_tls_wbuf};
		1372	delete $self->{filter_r};
		1373	delete $self->{filter_w};
		1374	}
		1375
		1376	sub DESTROY {
		1377	my $self = shift;
		1378
		1379	$self->stoptls;
		1380
		1381	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1382
		1383	if ($linger && length $self->{wbuf}) {
		1384	my $fh = delete $self->{fh};
		1385	my $wbuf = delete $self->{wbuf};
		1386
		1387	my @linger;
		1388
		1389	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1390	my $len = syswrite $fh, $wbuf, length $wbuf;
		1391
		1392	if ($len > 0) {
		1393	substr $wbuf, 0, $len, "";
		1394	} else {
		1395	@linger = (); # end
		1396	}
		1397	});
		1398	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1399	@linger = ();
		1400	});
		1401	}
		1402	}
		1403
		1404	=item AnyEvent::Handle::TLS_CTX
		1405
		1406	This function creates and returns the Net::SSLeay::CTX object used by
		1407	default for TLS mode.
		1408
		1409	The context is created like this:
		1410
		1411	Net::SSLeay::load_error_strings;
		1412	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1413	Net::SSLeay::randomize;
		1414
		1415	my $CTX = Net::SSLeay::CTX_new;
		1416
		1417	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1418
		1419	=cut
		1420
		1421	our $TLS_CTX;
		1422
		1423	sub TLS_CTX() {
		1424	$TLS_CTX || do {
		1425	require Net::SSLeay;
		1426
		1427	Net::SSLeay::load_error_strings ();
		1428	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1429	Net::SSLeay::randomize ();
		1430
		1431	$TLS_CTX = Net::SSLeay::CTX_new ();
		1432
		1433	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1434
		1435	$TLS_CTX
		1436	}
356	}	1437	}
357		1438
358	=back	1439	=back
359		1440
		1441	=head1 SUBCLASSING AnyEvent::Handle
		1442
		1443	In many cases, you might want to subclass AnyEvent::Handle.
		1444
		1445	To make this easier, a given version of AnyEvent::Handle uses these
		1446	conventions:
		1447
		1448	=over 4
		1449
		1450	=item * all constructor arguments become object members.
		1451
		1452	At least initially, when you pass a C<tls>-argument to the constructor it
		1453	will end up in C<< $handle->{tls} >>. Those members might be changes or
		1454	mutated later on (for example C<tls> will hold the TLS connection object).
		1455
		1456	=item * other object member names are prefixed with an C<_>.
		1457
		1458	All object members not explicitly documented (internal use) are prefixed
		1459	with an underscore character, so the remaining non-C<_>-namespace is free
		1460	for use for subclasses.
		1461
		1462	=item * all members not documented here and not prefixed with an underscore
		1463	are free to use in subclasses.
		1464
		1465	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1466	member variables, but thats just life, at least it is documented.
		1467
		1468	=back
		1469
360	=head1 AUTHOR	1470	=head1 AUTHOR
361		1471
362	Robin Redeker, C<< <elmex at ta-sa.org> >>	1472	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
363		1473
364	=cut	1474	=cut
365		1475
366	1; # End of AnyEvent::Handle	1476	1; # End of AnyEvent::Handle

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