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Revision 1.5 by elmex, Mon Apr 28 08:01:05 2008 UTC vs.
Revision 1.84 by root, Thu Aug 21 19:13:05 2008 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	use warnings;	3	no warnings;
4	use strict;	4	use strict qw(subs vars);
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 = 4.232;
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	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
		57	In the following, when the documentation refers to of "bytes" then this
		58	means characters. As sysread and syswrite are used for all I/O, their
		59	treatment of characters applies to this module as well.
		60
		61	All callbacks will be invoked with the handle object as their first
		62	argument.
		63
		64	=head1 METHODS
		65
		66	=over 4
		67
		68	=item B<new (%args)>
		69
		70	The constructor supports these arguments (all as key => value pairs).
		71
		72	=over 4
		73
		74	=item fh => $filehandle [MANDATORY]
		75
		76	The filehandle this L<AnyEvent::Handle> object will operate on.
		77
		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 on_eof => $cb->($handle)
		83
		84	Set the callback to be called when an end-of-file condition is detected,
		85	i.e. in the case of a socket, when the other side has closed the
		86	connection cleanly.
		87
		88	For sockets, this just means that the other side has stopped sending data,
		89	you can still try to write data, and, in fact, one can return from the eof
		90	callback and continue writing data, as only the read part has been shut
		91	down.
		92
		93	While not mandatory, it is I<highly> recommended to set an eof callback,
		94	otherwise you might end up with a closed socket while you are still
		95	waiting for data.
		96
		97	If an EOF condition has been detected but no C<on_eof> callback has been
		98	set, then a fatal error will be raised with C<$!> set to <0>.
		99
		100	=item on_error => $cb->($handle, $fatal)
		101
		102	This is the error callback, which is called when, well, some error
		103	occured, such as not being able to resolve the hostname, failure to
		104	connect or a read error.
		105
		106	Some errors are fatal (which is indicated by C<$fatal> being true). On
		107	fatal errors the handle object will be shut down and will not be usable
		108	(but you are free to look at the current C< ->rbuf >). Examples of fatal
		109	errors are an EOF condition with active (but unsatisifable) read watchers
		110	(C<EPIPE>) or I/O errors.
		111
		112	Non-fatal errors can be retried by simply returning, but it is recommended
		113	to simply ignore this parameter and instead abondon the handle object
		114	when this callback is invoked. Examples of non-fatal errors are timeouts
		115	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
		116
		117	On callback entrance, the value of C<$!> contains the operating system
		118	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
		119
		120	While not mandatory, it is I<highly> recommended to set this callback, as
		121	you will not be notified of errors otherwise. The default simply calls
		122	C<croak>.
		123
		124	=item on_read => $cb->($handle)
		125
		126	This sets the default read callback, which is called when data arrives
		127	and no read request is in the queue (unlike read queue callbacks, this
		128	callback will only be called when at least one octet of data is in the
		129	read buffer).
		130
		131	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		132	method or access the C<$handle->{rbuf}> member directly.
		133
		134	When an EOF condition is detected then AnyEvent::Handle will first try to
		135	feed all the remaining data to the queued callbacks and C<on_read> before
		136	calling the C<on_eof> callback. If no progress can be made, then a fatal
		137	error will be raised (with C<$!> set to C<EPIPE>).
		138
		139	=item on_drain => $cb->($handle)
		140
		141	This sets the callback that is called when the write buffer becomes empty
		142	(or when the callback is set and the buffer is empty already).
		143
		144	To append to the write buffer, use the C<< ->push_write >> method.
		145
		146	This callback is useful when you don't want to put all of your write data
		147	into the queue at once, for example, when you want to write the contents
		148	of some file to the socket you might not want to read the whole file into
		149	memory and push it into the queue, but instead only read more data from
		150	the file when the write queue becomes empty.
		151
		152	=item timeout => $fractional_seconds
		153
		154	If non-zero, then this enables an "inactivity" timeout: whenever this many
		155	seconds pass without a successful read or write on the underlying file
		156	handle, the C<on_timeout> callback will be invoked (and if that one is
		157	missing, an C<ETIMEDOUT> error will be raised).
		158
		159	Note that timeout processing is also active when you currently do not have
		160	any outstanding read or write requests: If you plan to keep the connection
		161	idle then you should disable the timout temporarily or ignore the timeout
		162	in the C<on_timeout> callback.
		163
		164	Zero (the default) disables this timeout.
		165
		166	=item on_timeout => $cb->($handle)
		167
		168	Called whenever the inactivity timeout passes. If you return from this
		169	callback, then the timeout will be reset as if some activity had happened,
		170	so this condition is not fatal in any way.
		171
		172	=item rbuf_max => <bytes>
		173
		174	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		175	when the read buffer ever (strictly) exceeds this size. This is useful to
		176	avoid denial-of-service attacks.
		177
		178	For example, a server accepting connections from untrusted sources should
		179	be configured to accept only so-and-so much data that it cannot act on
		180	(for example, when expecting a line, an attacker could send an unlimited
		181	amount of data without a callback ever being called as long as the line
		182	isn't finished).
		183
		184	=item autocork => <boolean>
		185
		186	When disabled (the default), then C<push_write> will try to immediately
		187	write the data to the handle if possible. This avoids having to register
		188	a write watcher and wait for the next event loop iteration, but can be
		189	inefficient if you write multiple small chunks (this disadvantage is
		190	usually avoided by your kernel's nagle algorithm, see C<low_delay>).
		191
		192	When enabled, then writes will always be queued till the next event loop
		193	iteration. This is efficient when you do many small writes per iteration,
		194	but less efficient when you do a single write only.
		195
		196	=item no_delay => <boolean>
		197
		198	When doing small writes on sockets, your operating system kernel might
		199	wait a bit for more data before actually sending it out. This is called
		200	the Nagle algorithm, and usually it is beneficial.
		201
		202	In some situations you want as low a delay as possible, which cna be
		203	accomplishd by setting this option to true.
		204
		205	The default is your opertaing system's default behaviour, this option
		206	explicitly enables or disables it, if possible.
		207
		208	=item read_size => <bytes>
		209
		210	The default read block size (the amount of bytes this module will try to read
		211	during each (loop iteration). Default: C<8192>.
		212
		213	=item low_water_mark => <bytes>
		214
		215	Sets the amount of bytes (default: C<0>) that make up an "empty" write
		216	buffer: If the write reaches this size or gets even samller it is
		217	considered empty.
		218
		219	=item linger => <seconds>
		220
		221	If non-zero (default: C<3600>), then the destructor of the
		222	AnyEvent::Handle object will check wether there is still outstanding write
		223	data and will install a watcher that will write out this data. No errors
		224	will be reported (this mostly matches how the operating system treats
		225	outstanding data at socket close time).
		226
		227	This will not work for partial TLS data that could not yet been
		228	encoded. This data will be lost.
		229
		230	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
		231
		232	When this parameter is given, it enables TLS (SSL) mode, that means it
		233	will start making tls handshake and will transparently encrypt/decrypt
		234	data.
		235
		236	TLS mode requires Net::SSLeay to be installed (it will be loaded
		237	automatically when you try to create a TLS handle).
		238
		239	For the TLS server side, use C<accept>, and for the TLS client side of a
		240	connection, use C<connect> mode.
		241
		242	You can also provide your own TLS connection object, but you have
		243	to make sure that you call either C<Net::SSLeay::set_connect_state>
		244	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		245	AnyEvent::Handle.
		246
		247	See the C<starttls> method if you need to start TLS negotiation later.
		248
		249	=item tls_ctx => $ssl_ctx
		250
		251	Use the given Net::SSLeay::CTX object to create the new TLS connection
		252	(unless a connection object was specified directly). If this parameter is
		253	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		254
		255	=item json => JSON or JSON::XS object
		256
		257	This is the json coder object used by the C<json> read and write types.
		258
		259	If you don't supply it, then AnyEvent::Handle will create and use a
		260	suitable one, which will write and expect UTF-8 encoded JSON texts.
		261
		262	Note that you are responsible to depend on the JSON module if you want to
		263	use this functionality, as AnyEvent does not have a dependency itself.
		264
		265	=item filter_r => $cb
		266
		267	=item filter_w => $cb
		268
		269	These exist, but are undocumented at this time.
		270
		271	=back
		272
		273	=cut
		274
		275	sub new {
		276	my $class = shift;
		277
		278	my $self = bless { @_ }, $class;
		279
		280	$self->{fh} or Carp::croak "mandatory argument fh is missing";
		281
		282	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
		283
		284	if ($self->{tls}) {
		285	require Net::SSLeay;
		286	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
		287	}
		288
		289	$self->{_activity} = AnyEvent->now;
		290	$self->_timeout;
		291
		292	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
		293	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
		294
		295	$self->start_read
		296	if $self->{on_read};
		297
		298	$self
		299	}
		300
		301	sub _shutdown {
		302	my ($self) = @_;
		303
		304	delete $self->{_tw};
		305	delete $self->{_rw};
		306	delete $self->{_ww};
		307	delete $self->{fh};
		308
		309	$self->stoptls;
		310
		311	delete $self->{on_read};
		312	delete $self->{_queue};
		313	}
		314
		315	sub _error {
		316	my ($self, $errno, $fatal) = @_;
		317
		318	$self->_shutdown
		319	if $fatal;
		320
		321	$! = $errno;
		322
		323	if ($self->{on_error}) {
		324	$self->{on_error}($self, $fatal);
		325	} else {
		326	Carp::croak "AnyEvent::Handle uncaught error: $!";
		327	}
		328	}
		329
		330	=item $fh = $handle->fh
		331
		332	This method returns the file handle of the L<AnyEvent::Handle> object.
		333
		334	=cut
		335
		336	sub fh { $_[0]{fh} }
		337
		338	=item $handle->on_error ($cb)
		339
		340	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
		341
		342	=cut
		343
		344	sub on_error {
		345	$_[0]{on_error} = $_[1];
		346	}
		347
		348	=item $handle->on_eof ($cb)
		349
		350	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
		351
		352	=cut
		353
		354	sub on_eof {
		355	$_[0]{on_eof} = $_[1];
		356	}
		357
		358	=item $handle->on_timeout ($cb)
		359
		360	Replace the current C<on_timeout> callback, or disables the callback
		361	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
		362	argument.
		363
		364	=cut
		365
		366	sub on_timeout {
		367	$_[0]{on_timeout} = $_[1];
		368	}
		369
		370	=item $handle->autocork ($boolean)
		371
		372	Enables or disables the current autocork behaviour (see C<autocork>
		373	constructor argument).
		374
		375	=cut
		376
		377	=item $handle->no_delay ($boolean)
		378
		379	Enables or disables the C<no_delay> setting (see constructor argument of
		380	the same name for details).
		381
		382	=cut
		383
		384	sub no_delay {
		385	$_[0]{no_delay} = $_[1];
		386
		387	eval {
		388	local $SIG{__DIE__};
		389	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		390	};
		391	}
		392
		393	#############################################################################
		394
		395	=item $handle->timeout ($seconds)
		396
		397	Configures (or disables) the inactivity timeout.
		398
		399	=cut
		400
		401	sub timeout {
		402	my ($self, $timeout) = @_;
		403
		404	$self->{timeout} = $timeout;
		405	$self->_timeout;
		406	}
		407
		408	# reset the timeout watcher, as neccessary
		409	# also check for time-outs
		410	sub _timeout {
		411	my ($self) = @_;
		412
		413	if ($self->{timeout}) {
		414	my $NOW = AnyEvent->now;
		415
		416	# when would the timeout trigger?
		417	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		418
		419	# now or in the past already?
		420	if ($after <= 0) {
		421	$self->{_activity} = $NOW;
		422
		423	if ($self->{on_timeout}) {
		424	$self->{on_timeout}($self);
		425	} else {
		426	$self->_error (&Errno::ETIMEDOUT);
		427	}
		428
		429	# callback could have changed timeout value, optimise
		430	return unless $self->{timeout};
		431
		432	# calculate new after
		433	$after = $self->{timeout};
		434	}
		435
		436	Scalar::Util::weaken $self;
		437	return unless $self; # ->error could have destroyed $self
		438
		439	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		440	delete $self->{_tw};
		441	$self->_timeout;
		442	});
		443	} else {
		444	delete $self->{_tw};
		445	}
		446	}
		447
		448	#############################################################################
		449
		450	=back
		451
		452	=head2 WRITE QUEUE
		453
		454	AnyEvent::Handle manages two queues per handle, one for writing and one
		455	for reading.
		456
		457	The write queue is very simple: you can add data to its end, and
		458	AnyEvent::Handle will automatically try to get rid of it for you.
		459
		460	When data could be written and the write buffer is shorter then the low
		461	water mark, the C<on_drain> callback will be invoked.
		462
		463	=over 4
		464
		465	=item $handle->on_drain ($cb)
		466
		467	Sets the C<on_drain> callback or clears it (see the description of
		468	C<on_drain> in the constructor).
		469
		470	=cut
		471
		472	sub on_drain {
		473	my ($self, $cb) = @_;
		474
		475	$self->{on_drain} = $cb;
		476
		477	$cb->($self)
		478	if $cb && $self->{low_water_mark} >= length $self->{wbuf};
		479	}
		480
		481	=item $handle->push_write ($data)
		482
		483	Queues the given scalar to be written. You can push as much data as you
		484	want (only limited by the available memory), as C<AnyEvent::Handle>
		485	buffers it independently of the kernel.
		486
		487	=cut
		488
		489	sub _drain_wbuf {
		490	my ($self) = @_;
		491
		492	if (!$self->{_ww} && length $self->{wbuf}) {
		493
		494	Scalar::Util::weaken $self;
		495
		496	my $cb = sub {
		497	my $len = syswrite $self->{fh}, $self->{wbuf};
		498
		499	if ($len >= 0) {
		500	substr $self->{wbuf}, 0, $len, "";
		501
		502	$self->{_activity} = AnyEvent->now;
		503
		504	$self->{on_drain}($self)
		505	if $self->{low_water_mark} >= length $self->{wbuf}
		506	&& $self->{on_drain};
		507
		508	delete $self->{_ww} unless length $self->{wbuf};
		509	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		510	$self->_error ($!, 1);
		511	}
		512	};
		513
		514	# try to write data immediately
		515	$cb->() unless $self->{autocork};
		516
		517	# if still data left in wbuf, we need to poll
		518	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
		519	if length $self->{wbuf};
		520	};
		521	}
		522
		523	our %WH;
		524
		525	sub register_write_type($$) {
		526	$WH{$_[0]} = $_[1];
		527	}
		528
		529	sub push_write {
		530	my $self = shift;
		531
		532	if (@_ > 1) {
		533	my $type = shift;
		534
		535	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		536	->($self, @_);
		537	}
		538
		539	if ($self->{filter_w}) {
		540	$self->{filter_w}($self, \$_[0]);
		541	} else {
		542	$self->{wbuf} .= $_[0];
		543	$self->_drain_wbuf;
		544	}
		545	}
		546
		547	=item $handle->push_write (type => @args)
		548
		549	Instead of formatting your data yourself, you can also let this module do
		550	the job by specifying a type and type-specific arguments.
		551
		552	Predefined types are (if you have ideas for additional types, feel free to
		553	drop by and tell us):
		554
		555	=over 4
		556
		557	=item netstring => $string
		558
		559	Formats the given value as netstring
		560	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		561
		562	=cut
		563
		564	register_write_type netstring => sub {
		565	my ($self, $string) = @_;
		566
		567	sprintf "%d:%s,", (length $string), $string
		568	};
		569
		570	=item packstring => $format, $data
		571
		572	An octet string prefixed with an encoded length. The encoding C<$format>
		573	uses the same format as a Perl C<pack> format, but must specify a single
		574	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		575	optional C<!>, C<< < >> or C<< > >> modifier).
		576
		577	=cut
		578
		579	register_write_type packstring => sub {
		580	my ($self, $format, $string) = @_;
		581
		582	pack "$format/a*", $string
		583	};
		584
		585	=item json => $array_or_hashref
		586
		587	Encodes the given hash or array reference into a JSON object. Unless you
		588	provide your own JSON object, this means it will be encoded to JSON text
		589	in UTF-8.
		590
		591	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		592	one end of a handle and read them at the other end without using any
		593	additional framing.
		594
		595	The generated JSON text is guaranteed not to contain any newlines: While
		596	this module doesn't need delimiters after or between JSON texts to be
		597	able to read them, many other languages depend on that.
		598
		599	A simple RPC protocol that interoperates easily with others is to send
		600	JSON arrays (or objects, although arrays are usually the better choice as
		601	they mimic how function argument passing works) and a newline after each
		602	JSON text:
		603
		604	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		605	$handle->push_write ("\012");
		606
		607	An AnyEvent::Handle receiver would simply use the C<json> read type and
		608	rely on the fact that the newline will be skipped as leading whitespace:
		609
		610	$handle->push_read (json => sub { my $array = $_[1]; ... });
		611
		612	Other languages could read single lines terminated by a newline and pass
		613	this line into their JSON decoder of choice.
		614
		615	=cut
		616
		617	register_write_type json => sub {
		618	my ($self, $ref) = @_;
		619
		620	require JSON;
		621
		622	$self->{json} ? $self->{json}->encode ($ref)
		623	: JSON::encode_json ($ref)
		624	};
		625
		626	=item storable => $reference
		627
		628	Freezes the given reference using L<Storable> and writes it to the
		629	handle. Uses the C<nfreeze> format.
		630
		631	=cut
		632
		633	register_write_type storable => sub {
		634	my ($self, $ref) = @_;
		635
		636	require Storable;
		637
		638	pack "w/a*", Storable::nfreeze ($ref)
		639	};
		640
		641	=back
		642
		643	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		644
		645	This function (not method) lets you add your own types to C<push_write>.
		646	Whenever the given C<type> is used, C<push_write> will invoke the code
		647	reference with the handle object and the remaining arguments.
		648
		649	The code reference is supposed to return a single octet string that will
		650	be appended to the write buffer.
		651
		652	Note that this is a function, and all types registered this way will be
		653	global, so try to use unique names.
		654
		655	=cut
		656
		657	#############################################################################
		658
		659	=back
		660
		661	=head2 READ QUEUE
		662
		663	AnyEvent::Handle manages two queues per handle, one for writing and one
		664	for reading.
		665
		666	The read queue is more complex than the write queue. It can be used in two
		667	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		668	a queue.
		669
		670	In the simple case, you just install an C<on_read> callback and whenever
		671	new data arrives, it will be called. You can then remove some data (if
		672	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
		673	leave the data there if you want to accumulate more (e.g. when only a
		674	partial message has been received so far).
		675
		676	In the more complex case, you want to queue multiple callbacks. In this
		677	case, AnyEvent::Handle will call the first queued callback each time new
		678	data arrives (also the first time it is queued) and removes it when it has
		679	done its job (see C<push_read>, below).
		680
		681	This way you can, for example, push three line-reads, followed by reading
		682	a chunk of data, and AnyEvent::Handle will execute them in order.
		683
		684	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		685	the specified number of bytes which give an XML datagram.
		686
		687	# in the default state, expect some header bytes
		688	$handle->on_read (sub {
		689	# some data is here, now queue the length-header-read (4 octets)
		690	shift->unshift_read (chunk => 4, sub {
		691	# header arrived, decode
		692	my $len = unpack "N", $_[1];
		693
		694	# now read the payload
		695	shift->unshift_read (chunk => $len, sub {
		696	my $xml = $_[1];
		697	# handle xml
		698	});
		699	});
		700	});
		701
		702	Example 2: Implement a client for a protocol that replies either with "OK"
		703	and another line or "ERROR" for the first request that is sent, and 64
		704	bytes for the second request. Due to the availability of a queue, we can
		705	just pipeline sending both requests and manipulate the queue as necessary
		706	in the callbacks.
		707
		708	When the first callback is called and sees an "OK" response, it will
		709	C<unshift> another line-read. This line-read will be queued I<before> the
		710	64-byte chunk callback.
		711
		712	# request one, returns either "OK + extra line" or "ERROR"
		713	$handle->push_write ("request 1\015\012");
		714
		715	# we expect "ERROR" or "OK" as response, so push a line read
		716	$handle->push_read (line => sub {
		717	# if we got an "OK", we have to _prepend_ another line,
		718	# so it will be read before the second request reads its 64 bytes
		719	# which are already in the queue when this callback is called
		720	# we don't do this in case we got an error
		721	if ($_[1] eq "OK") {
49	on_readline => sub {	722	$_[0]->unshift_read (line => sub {
50	my ($ae_fh, @lines) = @_;	723	my $response = $_[1];
51	for (@lines) {	724	...
52	chomp;	725	});
53	print "Line: $_";	726	}
		727	});
		728
		729	# request two, simply returns 64 octets
		730	$handle->push_write ("request 2\015\012");
		731
		732	# simply read 64 bytes, always
		733	$handle->push_read (chunk => 64, sub {
		734	my $response = $_[1];
		735	...
		736	});
		737
		738	=over 4
		739
		740	=cut
		741
		742	sub _drain_rbuf {
		743	my ($self) = @_;
		744
		745	local $self->{_in_drain} = 1;
		746
		747	if (
		748	defined $self->{rbuf_max}
		749	&& $self->{rbuf_max} < length $self->{rbuf}
		750	) {
		751	$self->_error (&Errno::ENOSPC, 1), return;
		752	}
		753
		754	while () {
		755	my $len = length $self->{rbuf};
		756
		757	if (my $cb = shift @{ $self->{_queue} }) {
		758	unless ($cb->($self)) {
		759	if ($self->{_eof}) {
		760	# no progress can be made (not enough data and no data forthcoming)
		761	$self->_error (&Errno::EPIPE, 1), return;
54	}	762	}
		763
		764	unshift @{ $self->{_queue} }, $cb;
		765	last;
55	}	766	}
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}) {	767	} elsif ($self->{on_read}) {
121	$self->readlines ($self->{on_readline});	768	last unless $len;
122		769
		770	$self->{on_read}($self);
		771
		772	if (
		773	$len == length $self->{rbuf} # if no data has been consumed
		774	&& !@{ $self->{_queue} } # and the queue is still empty
		775	&& $self->{on_read} # but we still have on_read
		776	) {
		777	# no further data will arrive
		778	# so no progress can be made
		779	$self->_error (&Errno::EPIPE, 1), return
		780	if $self->{_eof};
		781
		782	last; # more data might arrive
		783	}
		784	} else {
		785	# read side becomes idle
		786	delete $self->{_rw};
		787	last;
		788	}
		789	}
		790
123	} elsif ($self->{on_eof}) {	791	if ($self->{_eof}) {
124	$self->on_eof ($self->{on_eof});
125
126	} elsif ($self->{on_error}) {	792	if ($self->{on_eof}) {
127	$self->on_eof ($self->{on_error});	793	$self->{on_eof}($self)
		794	} else {
		795	$self->_error (0, 1);
		796	}
128	}	797	}
129		798
130	return $self	799	# may need to restart read watcher
		800	unless ($self->{_rw}) {
		801	$self->start_read
		802	if $self->{on_read} || @{ $self->{_queue} };
		803	}
131	}	804	}
132		805
133	=item B<fh>	806	=item $handle->on_read ($cb)
134		807
135	This method returns the filehandle of the L<AnyEvent::Handle> object.	808	This replaces the currently set C<on_read> callback, or clears it (when
136		809	the new callback is C<undef>). See the description of C<on_read> in the
137	=cut	810	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		811
149	=cut	812	=cut
150		813
151	sub on_read {	814	sub on_read {
152	my ($self, $cb) = @_;	815	my ($self, $cb) = @_;
		816
153	$self->{on_read} = $cb;	817	$self->{on_read} = $cb;
		818	$self->_drain_rbuf if $cb && !$self->{_in_drain};
		819	}
154		820
155	unless (defined $self->{on_read}) {	821	=item $handle->rbuf
156	delete $self->{on_read_w};	822
		823	Returns the read buffer (as a modifiable lvalue).
		824
		825	You can access the read buffer directly as the C<< ->{rbuf} >> member, if
		826	you want.
		827
		828	NOTE: The read buffer should only be used or modified if the C<on_read>,
		829	C<push_read> or C<unshift_read> methods are used. The other read methods
		830	automatically manage the read buffer.
		831
		832	=cut
		833
		834	sub rbuf : lvalue {
		835	$_[0]{rbuf}
		836	}
		837
		838	=item $handle->push_read ($cb)
		839
		840	=item $handle->unshift_read ($cb)
		841
		842	Append the given callback to the end of the queue (C<push_read>) or
		843	prepend it (C<unshift_read>).
		844
		845	The callback is called each time some additional read data arrives.
		846
		847	It must check whether enough data is in the read buffer already.
		848
		849	If not enough data is available, it must return the empty list or a false
		850	value, in which case it will be called repeatedly until enough data is
		851	available (or an error condition is detected).
		852
		853	If enough data was available, then the callback must remove all data it is
		854	interested in (which can be none at all) and return a true value. After returning
		855	true, it will be removed from the queue.
		856
		857	=cut
		858
		859	our %RH;
		860
		861	sub register_read_type($$) {
		862	$RH{$_[0]} = $_[1];
		863	}
		864
		865	sub push_read {
		866	my $self = shift;
		867	my $cb = pop;
		868
		869	if (@_) {
		870	my $type = shift;
		871
		872	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		873	->($self, $cb, @_);
		874	}
		875
		876	push @{ $self->{_queue} }, $cb;
		877	$self->_drain_rbuf unless $self->{_in_drain};
		878	}
		879
		880	sub unshift_read {
		881	my $self = shift;
		882	my $cb = pop;
		883
		884	if (@_) {
		885	my $type = shift;
		886
		887	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		888	->($self, $cb, @_);
		889	}
		890
		891
		892	unshift @{ $self->{_queue} }, $cb;
		893	$self->_drain_rbuf unless $self->{_in_drain};
		894	}
		895
		896	=item $handle->push_read (type => @args, $cb)
		897
		898	=item $handle->unshift_read (type => @args, $cb)
		899
		900	Instead of providing a callback that parses the data itself you can chose
		901	between a number of predefined parsing formats, for chunks of data, lines
		902	etc.
		903
		904	Predefined types are (if you have ideas for additional types, feel free to
		905	drop by and tell us):
		906
		907	=over 4
		908
		909	=item chunk => $octets, $cb->($handle, $data)
		910
		911	Invoke the callback only once C<$octets> bytes have been read. Pass the
		912	data read to the callback. The callback will never be called with less
		913	data.
		914
		915	Example: read 2 bytes.
		916
		917	$handle->push_read (chunk => 2, sub {
		918	warn "yay ", unpack "H*", $_[1];
		919	});
		920
		921	=cut
		922
		923	register_read_type chunk => sub {
		924	my ($self, $cb, $len) = @_;
		925
		926	sub {
		927	$len <= length $_[0]{rbuf} or return;
		928	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
		929	1
		930	}
		931	};
		932
		933	=item line => [$eol, ]$cb->($handle, $line, $eol)
		934
		935	The callback will be called only once a full line (including the end of
		936	line marker, C<$eol>) has been read. This line (excluding the end of line
		937	marker) will be passed to the callback as second argument (C<$line>), and
		938	the end of line marker as the third argument (C<$eol>).
		939
		940	The end of line marker, C<$eol>, can be either a string, in which case it
		941	will be interpreted as a fixed record end marker, or it can be a regex
		942	object (e.g. created by C<qr>), in which case it is interpreted as a
		943	regular expression.
		944
		945	The end of line marker argument C<$eol> is optional, if it is missing (NOT
		946	undef), then C<qr|\015?\012|> is used (which is good for most internet
		947	protocols).
		948
		949	Partial lines at the end of the stream will never be returned, as they are
		950	not marked by the end of line marker.
		951
		952	=cut
		953
		954	register_read_type line => sub {
		955	my ($self, $cb, $eol) = @_;
		956
		957	if (@_ < 3) {
		958	# this is more than twice as fast as the generic code below
		959	sub {
		960	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		961
		962	$cb->($_[0], $1, $2);
		963	1
		964	}
		965	} else {
		966	$eol = quotemeta $eol unless ref $eol;
		967	$eol = qr|^(.*?)($eol)|s;
		968
		969	sub {
		970	$_[0]{rbuf} =~ s/$eol// or return;
		971
		972	$cb->($_[0], $1, $2);
		973	1
		974	}
		975	}
		976	};
		977
		978	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		979
		980	Makes a regex match against the regex object C<$accept> and returns
		981	everything up to and including the match.
		982
		983	Example: read a single line terminated by '\n'.
		984
		985	$handle->push_read (regex => qr<\n>, sub { ... });
		986
		987	If C<$reject> is given and not undef, then it determines when the data is
		988	to be rejected: it is matched against the data when the C<$accept> regex
		989	does not match and generates an C<EBADMSG> error when it matches. This is
		990	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		991	receive buffer overflow).
		992
		993	Example: expect a single decimal number followed by whitespace, reject
		994	anything else (not the use of an anchor).
		995
		996	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		997
		998	If C<$skip> is given and not C<undef>, then it will be matched against
		999	the receive buffer when neither C<$accept> nor C<$reject> match,
		1000	and everything preceding and including the match will be accepted
		1001	unconditionally. This is useful to skip large amounts of data that you
		1002	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1003	have to start matching from the beginning. This is purely an optimisation
		1004	and is usually worth only when you expect more than a few kilobytes.
		1005
		1006	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1007	expect the header to be very large (it isn't in practise, but...), we use
		1008	a skip regex to skip initial portions. The skip regex is tricky in that
		1009	it only accepts something not ending in either \015 or \012, as these are
		1010	required for the accept regex.
		1011
		1012	$handle->push_read (regex =>
		1013	qr<\015\012\015\012>,
		1014	undef, # no reject
		1015	qr<^.*[^\015\012]>,
		1016	sub { ... });
		1017
		1018	=cut
		1019
		1020	register_read_type regex => sub {
		1021	my ($self, $cb, $accept, $reject, $skip) = @_;
		1022
		1023	my $data;
		1024	my $rbuf = \$self->{rbuf};
		1025
		1026	sub {
		1027	# accept
		1028	if ($$rbuf =~ $accept) {
		1029	$data .= substr $$rbuf, 0, $+[0], "";
		1030	$cb->($self, $data);
157	return;	1031	return 1;
		1032	}
		1033
		1034	# reject
		1035	if ($reject && $$rbuf =~ $reject) {
		1036	$self->_error (&Errno::EBADMSG);
		1037	}
		1038
		1039	# skip
		1040	if ($skip && $$rbuf =~ $skip) {
		1041	$data .= substr $$rbuf, 0, $+[0], "";
		1042	}
		1043
		1044	()
158	}	1045	}
159		1046	};
160	$self->{on_read_w} =	1047
161	AnyEvent->io (poll => 'r', fh => $self->{fh}, cb => sub {	1048	=item netstring => $cb->($handle, $string)
162	#d# warn "READ:[$self->{read_size}] $self->{read_block_size} : ".length ($self->{rbuf})."\n";	1049
163	my $rbuf_len = length $self->{rbuf};	1050	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
164	my $l;	1051
165	if (defined $self->{read_size}) {	1052	Throws an error with C<$!> set to EBADMSG on format violations.
166	$l = sysread $self->{fh}, $self->{rbuf},	1053
167	($self->{read_size} - $rbuf_len), $rbuf_len;	1054	=cut
168	} else {	1055
169	$l = sysread $self->{fh}, $self->{rbuf}, $self->{read_block_size}, $rbuf_len;	1056	register_read_type netstring => sub {
		1057	my ($self, $cb) = @_;
		1058
		1059	sub {
		1060	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1061	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1062	$self->_error (&Errno::EBADMSG);
170	}	1063	}
171	#d# warn "READL $l [$self->{rbuf}]\n";	1064	return;
		1065	}
172		1066
173	if (not defined $l) {	1067	my $len = $1;
174	return if $! == EAGAIN || $! == EINTR;
175	$self->{on_error}->($self) if $self->{on_error};
176	delete $self->{on_read_w};
177		1068
178	} elsif ($l == 0) {	1069	$self->unshift_read (chunk => $len, sub {
179	$self->{on_eof}->($self) if $self->{on_eof};	1070	my $string = $_[1];
180	delete $self->{on_read_w};	1071	$_[0]->unshift_read (chunk => 1, sub {
181		1072	if ($_[1] eq ",") {
		1073	$cb->($_[0], $string);
182	} else {	1074	} else {
183	$self->{on_read}->($self);	1075	$self->_error (&Errno::EBADMSG);
		1076	}
		1077	});
		1078	});
		1079
		1080	1
		1081	}
		1082	};
		1083
		1084	=item packstring => $format, $cb->($handle, $string)
		1085
		1086	An octet string prefixed with an encoded length. The encoding C<$format>
		1087	uses the same format as a Perl C<pack> format, but must specify a single
		1088	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1089	optional C<!>, C<< < >> or C<< > >> modifier).
		1090
		1091	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.
		1092
		1093	Example: read a block of data prefixed by its length in BER-encoded
		1094	format (very efficient).
		1095
		1096	$handle->push_read (packstring => "w", sub {
		1097	my ($handle, $data) = @_;
		1098	});
		1099
		1100	=cut
		1101
		1102	register_read_type packstring => sub {
		1103	my ($self, $cb, $format) = @_;
		1104
		1105	sub {
		1106	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1107	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1108	or return;
		1109
		1110	$format = length pack $format, $len;
		1111
		1112	# bypass unshift if we already have the remaining chunk
		1113	if ($format + $len <= length $_[0]{rbuf}) {
		1114	my $data = substr $_[0]{rbuf}, $format, $len;
		1115	substr $_[0]{rbuf}, 0, $format + $len, "";
		1116	$cb->($_[0], $data);
		1117	} else {
		1118	# remove prefix
		1119	substr $_[0]{rbuf}, 0, $format, "";
		1120
		1121	# read remaining chunk
		1122	$_[0]->unshift_read (chunk => $len, $cb);
		1123	}
		1124
		1125	1
		1126	}
		1127	};
		1128
		1129	=item json => $cb->($handle, $hash_or_arrayref)
		1130
		1131	Reads a JSON object or array, decodes it and passes it to the callback.
		1132
		1133	If a C<json> object was passed to the constructor, then that will be used
		1134	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1135
		1136	This read type uses the incremental parser available with JSON version
		1137	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1138	dependency on your own: this module will load the JSON module, but
		1139	AnyEvent does not depend on it itself.
		1140
		1141	Since JSON texts are fully self-delimiting, the C<json> read and write
		1142	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1143	the C<json> write type description, above, for an actual example.
		1144
		1145	=cut
		1146
		1147	register_read_type json => sub {
		1148	my ($self, $cb) = @_;
		1149
		1150	require JSON;
		1151
		1152	my $data;
		1153	my $rbuf = \$self->{rbuf};
		1154
		1155	my $json = $self->{json} ||= JSON->new->utf8;
		1156
		1157	sub {
		1158	my $ref = $json->incr_parse ($self->{rbuf});
		1159
		1160	if ($ref) {
		1161	$self->{rbuf} = $json->incr_text;
		1162	$json->incr_text = "";
		1163	$cb->($self, $ref);
		1164
		1165	1
		1166	} else {
		1167	$self->{rbuf} = "";
		1168	()
		1169	}
		1170	}
		1171	};
		1172
		1173	=item storable => $cb->($handle, $ref)
		1174
		1175	Deserialises a L<Storable> frozen representation as written by the
		1176	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1177	data).
		1178
		1179	Raises C<EBADMSG> error if the data could not be decoded.
		1180
		1181	=cut
		1182
		1183	register_read_type storable => sub {
		1184	my ($self, $cb) = @_;
		1185
		1186	require Storable;
		1187
		1188	sub {
		1189	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1190	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1191	or return;
		1192
		1193	my $format = length pack "w", $len;
		1194
		1195	# bypass unshift if we already have the remaining chunk
		1196	if ($format + $len <= length $_[0]{rbuf}) {
		1197	my $data = substr $_[0]{rbuf}, $format, $len;
		1198	substr $_[0]{rbuf}, 0, $format + $len, "";
		1199	$cb->($_[0], Storable::thaw ($data));
		1200	} else {
		1201	# remove prefix
		1202	substr $_[0]{rbuf}, 0, $format, "";
		1203
		1204	# read remaining chunk
		1205	$_[0]->unshift_read (chunk => $len, sub {
		1206	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1207	$cb->($_[0], $ref);
		1208	} else {
		1209	$self->_error (&Errno::EBADMSG);
		1210	}
		1211	});
		1212	}
		1213
		1214	1
		1215	}
		1216	};
		1217
		1218	=back
		1219
		1220	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1221
		1222	This function (not method) lets you add your own types to C<push_read>.
		1223
		1224	Whenever the given C<type> is used, C<push_read> will invoke the code
		1225	reference with the handle object, the callback and the remaining
		1226	arguments.
		1227
		1228	The code reference is supposed to return a callback (usually a closure)
		1229	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1230
		1231	It should invoke the passed callback when it is done reading (remember to
		1232	pass C<$handle> as first argument as all other callbacks do that).
		1233
		1234	Note that this is a function, and all types registered this way will be
		1235	global, so try to use unique names.
		1236
		1237	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1238	search for C<register_read_type>)).
		1239
		1240	=item $handle->stop_read
		1241
		1242	=item $handle->start_read
		1243
		1244	In rare cases you actually do not want to read anything from the
		1245	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
		1246	any queued callbacks will be executed then. To start reading again, call
		1247	C<start_read>.
		1248
		1249	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1250	you change the C<on_read> callback or push/unshift a read callback, and it
		1251	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1252	there are any read requests in the queue.
		1253
		1254	=cut
		1255
		1256	sub stop_read {
		1257	my ($self) = @_;
		1258
		1259	delete $self->{_rw};
		1260	}
		1261
		1262	sub start_read {
		1263	my ($self) = @_;
		1264
		1265	unless ($self->{_rw} || $self->{_eof}) {
		1266	Scalar::Util::weaken $self;
		1267
		1268	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
		1269	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
		1270	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
		1271
		1272	if ($len > 0) {
		1273	$self->{_activity} = AnyEvent->now;
		1274
		1275	$self->{filter_r}
		1276	? $self->{filter_r}($self, $rbuf)
		1277	: $self->{_in_drain} || $self->_drain_rbuf;
		1278
		1279	} elsif (defined $len) {
		1280	delete $self->{_rw};
		1281	$self->{_eof} = 1;
		1282	$self->_drain_rbuf unless $self->{_in_drain};
		1283
		1284	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		1285	return $self->_error ($!, 1);
184	}	1286	}
185	});	1287	});
		1288	}
186	}	1289	}
187		1290
188	=item B<on_error ($callback)>	1291	sub _dotls {
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) = @_;	1292	my ($self) = @_;
240		1293
241	$self->{read_cb} = $cb;	1294	my $buf;
242	my $old_blk_size = $self->{read_block_size};
243	$self->{read_block_size} = $len;
244		1295
245	$self->on_read (sub {	1296	if (length $self->{_tls_wbuf}) {
246	#d# warn "OFOFO $len || ".length($_[0]->{rbuf})."||\n";	1297	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
247		1298	substr $self->{_tls_wbuf}, 0, $len, "";
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	}	1299	}
253	});	1300	}
254	}
255		1301
256	=item B<readlines ($callback)>	1302	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
257		1303	$self->{wbuf} .= $buf;
258	=item B<readlines ($sep, $callback)>	1304	$self->_drain_wbuf;
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 "line" seperator.
262
263	The C<$callback> will be called when at least one
264	line could be read. The first argument to the C<$callback> will be the L<AnyEvent::Handle>
265	object itself and the rest of the arguments will be the read lines.
266
267	NOTE: This method will override any callbacks installed via the C<on_read> method.
268
269	=cut
270
271	sub readlines {
272	my ($self, $sep, $cb) = @_;
273
274	if (ref $sep) {
275	$cb = $sep;
276	$sep = "\n";
277
278	} elsif (not defined $sep) {
279	$sep = "\n";
280	}	1305	}
281		1306
282	my $sep_len = length $sep;	1307	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
283		1308	if (length $buf) {
284	$self->{on_readline} = $cb;	1309	$self->{rbuf} .= $buf;
285		1310	$self->_drain_rbuf unless $self->{_in_drain};
286	$self->on_read (sub {	1311	} else {
287	my @lines;	1312	# let's treat SSL-eof as we treat normal EOF
288	my $rb = \$_[0]->{rbuf};	1313	$self->{_eof} = 1;
289	my $pos;	1314	$self->_shutdown;
290	while (($pos = index ($$rb, $sep)) >= 0) {	1315	return;
291	push @lines, substr $$rb, 0, $pos + $sep_len, '';
292	}	1316	}
293	$self->{on_readline}->($_[0], @lines);	1317	}
		1318
		1319	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1320
		1321	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1322	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1323	return $self->_error ($!, 1);
		1324	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1325	return $self->_error (&Errno::EIO, 1);
		1326	}
		1327
		1328	# all others are fine for our purposes
		1329	}
		1330	}
		1331
		1332	=item $handle->starttls ($tls[, $tls_ctx])
		1333
		1334	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1335	object is created, you can also do that at a later time by calling
		1336	C<starttls>.
		1337
		1338	The first argument is the same as the C<tls> constructor argument (either
		1339	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1340
		1341	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1342	used when AnyEvent::Handle has to create its own TLS connection object.
		1343
		1344	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1345	call and can be used or changed to your liking. Note that the handshake
		1346	might have already started when this function returns.
		1347
		1348	=cut
		1349
		1350	sub starttls {
		1351	my ($self, $ssl, $ctx) = @_;
		1352
		1353	$self->stoptls;
		1354
		1355	if ($ssl eq "accept") {
		1356	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1357	Net::SSLeay::set_accept_state ($ssl);
		1358	} elsif ($ssl eq "connect") {
		1359	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1360	Net::SSLeay::set_connect_state ($ssl);
		1361	}
		1362
		1363	$self->{tls} = $ssl;
		1364
		1365	# basically, this is deep magic (because SSL_read should have the same issues)
		1366	# but the openssl maintainers basically said: "trust us, it just works".
		1367	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1368	# and mismaintained ssleay-module doesn't even offer them).
		1369	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1370	Net::SSLeay::CTX_set_mode ($self->{tls},
		1371	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1372	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1373
		1374	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1375	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1376
		1377	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1378
		1379	$self->{filter_w} = sub {
		1380	$_[0]{_tls_wbuf} .= ${$_[1]};
		1381	&_dotls;
294	});	1382	};
		1383	$self->{filter_r} = sub {
		1384	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
		1385	&_dotls;
		1386	};
295	}	1387	}
296		1388
297	=item B<write ($data)>	1389	=item $handle->stoptls
298		1390
299	=item B<write ($callback)>	1391	Destroys the SSL connection, if any. Partial read or write data will be
		1392	lost.
300		1393
301	=item B<write ($data, $callback)>
302
303	This method will write C<$data> to the filehandle and call the C<$callback>
304	afterwards. If only C<$callback> is provided it will be called when the
305	write buffer becomes empty the next time (or immediately if it already is empty).
306
307	=cut	1394	=cut
308		1395
309	sub write {	1396	sub stoptls {
310	my ($self, $data, $cb) = @_;
311	if (ref $data) { $cb = $data; undef $data }
312	push @{$self->{write_bufs}}, [$data, $cb];
313	$self->_check_writer;
314	}
315
316	sub _check_writer {
317	my ($self) = @_;	1397	my ($self) = @_;
318		1398
319	if ($self->{write_w}) {	1399	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};
320	unless ($self->{write_cb}) {
321	while (@{$self->{write_bufs}} && not defined $self->{write_bufs}->[0]->[1]) {
322	my $wba = shift @{$self->{write_bufs}};
323	$self->{wbuf} .= $wba->[0];
324	}
325	}
326	return;
327	}
328		1400
329	my $wba = shift @{$self->{write_bufs}}	1401	delete $self->{_rbio};
330	or return;	1402	delete $self->{_wbio};
		1403	delete $self->{_tls_wbuf};
		1404	delete $self->{filter_r};
		1405	delete $self->{filter_w};
		1406	}
331		1407
332	unless (defined $wba->[0]) {	1408	sub DESTROY {
333	$wba->[1]->($self) if $wba->[1];	1409	my $self = shift;
334	$self->_check_writer;
335	return;
336	}
337		1410
338	$self->{wbuf} = $wba->[0];	1411	$self->stoptls;
339	$self->{write_cb} = $wba->[1];
340		1412
341	$self->{write_w} =	1413	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
342	AnyEvent->io (poll => 'w', fh => $self->{fh}, cb => sub {	1414
		1415	if ($linger && length $self->{wbuf}) {
		1416	my $fh = delete $self->{fh};
		1417	my $wbuf = delete $self->{wbuf};
		1418
		1419	my @linger;
		1420
		1421	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
343	my $l = syswrite $self->{fh}, $self->{wbuf}, length $self->{wbuf};	1422	my $len = syswrite $fh, $wbuf, length $wbuf;
344		1423
345	if (not defined $l) {	1424	if ($len > 0) {
346	return if $! == EAGAIN || $! == EINTR;	1425	substr $wbuf, 0, $len, "";
347	delete $self->{write_w};
348	$self->{on_error}->($self) if $self->{on_error};
349
350	} else {	1426	} else {
351	substr $self->{wbuf}, 0, $l, '';	1427	@linger = (); # end
352
353	if (length ($self->{wbuf}) == 0) {
354	$self->{write_cb}->($self) if $self->{write_cb};
355
356	delete $self->{write_w};
357	delete $self->{wbuf};
358	delete $self->{write_cb};
359
360	$self->_check_writer;
361	}
362	}	1428	}
363	});	1429	});
		1430	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1431	@linger = ();
		1432	});
		1433	}
		1434	}
		1435
		1436	=item AnyEvent::Handle::TLS_CTX
		1437
		1438	This function creates and returns the Net::SSLeay::CTX object used by
		1439	default for TLS mode.
		1440
		1441	The context is created like this:
		1442
		1443	Net::SSLeay::load_error_strings;
		1444	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1445	Net::SSLeay::randomize;
		1446
		1447	my $CTX = Net::SSLeay::CTX_new;
		1448
		1449	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1450
		1451	=cut
		1452
		1453	our $TLS_CTX;
		1454
		1455	sub TLS_CTX() {
		1456	$TLS_CTX || do {
		1457	require Net::SSLeay;
		1458
		1459	Net::SSLeay::load_error_strings ();
		1460	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1461	Net::SSLeay::randomize ();
		1462
		1463	$TLS_CTX = Net::SSLeay::CTX_new ();
		1464
		1465	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1466
		1467	$TLS_CTX
		1468	}
364	}	1469	}
365		1470
366	=back	1471	=back
367		1472
		1473	=head1 SUBCLASSING AnyEvent::Handle
		1474
		1475	In many cases, you might want to subclass AnyEvent::Handle.
		1476
		1477	To make this easier, a given version of AnyEvent::Handle uses these
		1478	conventions:
		1479
		1480	=over 4
		1481
		1482	=item * all constructor arguments become object members.
		1483
		1484	At least initially, when you pass a C<tls>-argument to the constructor it
		1485	will end up in C<< $handle->{tls} >>. Those members might be changed or
		1486	mutated later on (for example C<tls> will hold the TLS connection object).
		1487
		1488	=item * other object member names are prefixed with an C<_>.
		1489
		1490	All object members not explicitly documented (internal use) are prefixed
		1491	with an underscore character, so the remaining non-C<_>-namespace is free
		1492	for use for subclasses.
		1493
		1494	=item * all members not documented here and not prefixed with an underscore
		1495	are free to use in subclasses.
		1496
		1497	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1498	member variables, but thats just life, at least it is documented.
		1499
		1500	=back
		1501
368	=head1 AUTHOR	1502	=head1 AUTHOR
369		1503
370	Robin Redeker, C<< <elmex at ta-sa.org> >>	1504	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
371		1505
372	=cut	1506	=cut
373		1507
374	1; # End of AnyEvent::Handle	1508	1; # End of AnyEvent::Handle

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