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Revision 1.6 by elmex, Mon Apr 28 09:27:47 2008 UTC vs.
Revision 1.86 by root, Thu Aug 21 20:41:16 2008 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	no 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
		233	AnyEvent will start a 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	Unlike TCP, TLS has a server and client side: for the TLS server side, use
		240	C<accept>, and for the TLS client side of a connection, use C<connect>
		241	mode.
		242
		243	You can also provide your own TLS connection object, but you have
		244	to make sure that you call either C<Net::SSLeay::set_connect_state>
		245	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		246	AnyEvent::Handle.
		247
		248	See the C<starttls> method for when need to start TLS negotiation later.
		249
		250	=item tls_ctx => $ssl_ctx
		251
		252	Use the given Net::SSLeay::CTX object to create the new TLS connection
		253	(unless a connection object was specified directly). If this parameter is
		254	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		255
		256	=item json => JSON or JSON::XS object
		257
		258	This is the json coder object used by the C<json> read and write types.
		259
		260	If you don't supply it, then AnyEvent::Handle will create and use a
		261	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		262	texts.
		263
		264	Note that you are responsible to depend on the JSON module if you want to
		265	use this functionality, as AnyEvent does not have a dependency itself.
		266
		267	=item filter_r => $cb
		268
		269	=item filter_w => $cb
		270
		271	These exist, but are undocumented at this time.
		272
		273	=back
		274
		275	=cut
		276
		277	sub new {
		278	my $class = shift;
		279
		280	my $self = bless { @_ }, $class;
		281
		282	$self->{fh} or Carp::croak "mandatory argument fh is missing";
		283
		284	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
		285
		286	if ($self->{tls}) {
		287	require Net::SSLeay;
		288	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
		289	}
		290
		291	$self->{_activity} = AnyEvent->now;
		292	$self->_timeout;
		293
		294	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
		295	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
		296
		297	$self->start_read
		298	if $self->{on_read};
		299
		300	$self
		301	}
		302
		303	sub _shutdown {
		304	my ($self) = @_;
		305
		306	delete $self->{_tw};
		307	delete $self->{_rw};
		308	delete $self->{_ww};
		309	delete $self->{fh};
		310
		311	$self->stoptls;
		312
		313	delete $self->{on_read};
		314	delete $self->{_queue};
		315	}
		316
		317	sub _error {
		318	my ($self, $errno, $fatal) = @_;
		319
		320	$self->_shutdown
		321	if $fatal;
		322
		323	$! = $errno;
		324
		325	if ($self->{on_error}) {
		326	$self->{on_error}($self, $fatal);
		327	} else {
		328	Carp::croak "AnyEvent::Handle uncaught error: $!";
		329	}
		330	}
		331
		332	=item $fh = $handle->fh
		333
		334	This method returns the file handle of the L<AnyEvent::Handle> object.
		335
		336	=cut
		337
		338	sub fh { $_[0]{fh} }
		339
		340	=item $handle->on_error ($cb)
		341
		342	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
		343
		344	=cut
		345
		346	sub on_error {
		347	$_[0]{on_error} = $_[1];
		348	}
		349
		350	=item $handle->on_eof ($cb)
		351
		352	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
		353
		354	=cut
		355
		356	sub on_eof {
		357	$_[0]{on_eof} = $_[1];
		358	}
		359
		360	=item $handle->on_timeout ($cb)
		361
		362	Replace the current C<on_timeout> callback, or disables the callback
		363	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
		364	argument.
		365
		366	=cut
		367
		368	sub on_timeout {
		369	$_[0]{on_timeout} = $_[1];
		370	}
		371
		372	=item $handle->autocork ($boolean)
		373
		374	Enables or disables the current autocork behaviour (see C<autocork>
		375	constructor argument).
		376
		377	=cut
		378
		379	=item $handle->no_delay ($boolean)
		380
		381	Enables or disables the C<no_delay> setting (see constructor argument of
		382	the same name for details).
		383
		384	=cut
		385
		386	sub no_delay {
		387	$_[0]{no_delay} = $_[1];
		388
		389	eval {
		390	local $SIG{__DIE__};
		391	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		392	};
		393	}
		394
		395	#############################################################################
		396
		397	=item $handle->timeout ($seconds)
		398
		399	Configures (or disables) the inactivity timeout.
		400
		401	=cut
		402
		403	sub timeout {
		404	my ($self, $timeout) = @_;
		405
		406	$self->{timeout} = $timeout;
		407	$self->_timeout;
		408	}
		409
		410	# reset the timeout watcher, as neccessary
		411	# also check for time-outs
		412	sub _timeout {
		413	my ($self) = @_;
		414
		415	if ($self->{timeout}) {
		416	my $NOW = AnyEvent->now;
		417
		418	# when would the timeout trigger?
		419	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		420
		421	# now or in the past already?
		422	if ($after <= 0) {
		423	$self->{_activity} = $NOW;
		424
		425	if ($self->{on_timeout}) {
		426	$self->{on_timeout}($self);
		427	} else {
		428	$self->_error (&Errno::ETIMEDOUT);
		429	}
		430
		431	# callback could have changed timeout value, optimise
		432	return unless $self->{timeout};
		433
		434	# calculate new after
		435	$after = $self->{timeout};
		436	}
		437
		438	Scalar::Util::weaken $self;
		439	return unless $self; # ->error could have destroyed $self
		440
		441	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		442	delete $self->{_tw};
		443	$self->_timeout;
		444	});
		445	} else {
		446	delete $self->{_tw};
		447	}
		448	}
		449
		450	#############################################################################
		451
		452	=back
		453
		454	=head2 WRITE QUEUE
		455
		456	AnyEvent::Handle manages two queues per handle, one for writing and one
		457	for reading.
		458
		459	The write queue is very simple: you can add data to its end, and
		460	AnyEvent::Handle will automatically try to get rid of it for you.
		461
		462	When data could be written and the write buffer is shorter then the low
		463	water mark, the C<on_drain> callback will be invoked.
		464
		465	=over 4
		466
		467	=item $handle->on_drain ($cb)
		468
		469	Sets the C<on_drain> callback or clears it (see the description of
		470	C<on_drain> in the constructor).
		471
		472	=cut
		473
		474	sub on_drain {
		475	my ($self, $cb) = @_;
		476
		477	$self->{on_drain} = $cb;
		478
		479	$cb->($self)
		480	if $cb && $self->{low_water_mark} >= length $self->{wbuf};
		481	}
		482
		483	=item $handle->push_write ($data)
		484
		485	Queues the given scalar to be written. You can push as much data as you
		486	want (only limited by the available memory), as C<AnyEvent::Handle>
		487	buffers it independently of the kernel.
		488
		489	=cut
		490
		491	sub _drain_wbuf {
		492	my ($self) = @_;
		493
		494	if (!$self->{_ww} && length $self->{wbuf}) {
		495
		496	Scalar::Util::weaken $self;
		497
		498	my $cb = sub {
		499	my $len = syswrite $self->{fh}, $self->{wbuf};
		500
		501	if ($len >= 0) {
		502	substr $self->{wbuf}, 0, $len, "";
		503
		504	$self->{_activity} = AnyEvent->now;
		505
		506	$self->{on_drain}($self)
		507	if $self->{low_water_mark} >= length $self->{wbuf}
		508	&& $self->{on_drain};
		509
		510	delete $self->{_ww} unless length $self->{wbuf};
		511	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		512	$self->_error ($!, 1);
		513	}
		514	};
		515
		516	# try to write data immediately
		517	$cb->() unless $self->{autocork};
		518
		519	# if still data left in wbuf, we need to poll
		520	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
		521	if length $self->{wbuf};
		522	};
		523	}
		524
		525	our %WH;
		526
		527	sub register_write_type($$) {
		528	$WH{$_[0]} = $_[1];
		529	}
		530
		531	sub push_write {
		532	my $self = shift;
		533
		534	if (@_ > 1) {
		535	my $type = shift;
		536
		537	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		538	->($self, @_);
		539	}
		540
		541	if ($self->{filter_w}) {
		542	$self->{filter_w}($self, \$_[0]);
		543	} else {
		544	$self->{wbuf} .= $_[0];
		545	$self->_drain_wbuf;
		546	}
		547	}
		548
		549	=item $handle->push_write (type => @args)
		550
		551	Instead of formatting your data yourself, you can also let this module do
		552	the job by specifying a type and type-specific arguments.
		553
		554	Predefined types are (if you have ideas for additional types, feel free to
		555	drop by and tell us):
		556
		557	=over 4
		558
		559	=item netstring => $string
		560
		561	Formats the given value as netstring
		562	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		563
		564	=cut
		565
		566	register_write_type netstring => sub {
		567	my ($self, $string) = @_;
		568
		569	sprintf "%d:%s,", (length $string), $string
		570	};
		571
		572	=item packstring => $format, $data
		573
		574	An octet string prefixed with an encoded length. The encoding C<$format>
		575	uses the same format as a Perl C<pack> format, but must specify a single
		576	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		577	optional C<!>, C<< < >> or C<< > >> modifier).
		578
		579	=cut
		580
		581	register_write_type packstring => sub {
		582	my ($self, $format, $string) = @_;
		583
		584	pack "$format/a*", $string
		585	};
		586
		587	=item json => $array_or_hashref
		588
		589	Encodes the given hash or array reference into a JSON object. Unless you
		590	provide your own JSON object, this means it will be encoded to JSON text
		591	in UTF-8.
		592
		593	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		594	one end of a handle and read them at the other end without using any
		595	additional framing.
		596
		597	The generated JSON text is guaranteed not to contain any newlines: While
		598	this module doesn't need delimiters after or between JSON texts to be
		599	able to read them, many other languages depend on that.
		600
		601	A simple RPC protocol that interoperates easily with others is to send
		602	JSON arrays (or objects, although arrays are usually the better choice as
		603	they mimic how function argument passing works) and a newline after each
		604	JSON text:
		605
		606	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		607	$handle->push_write ("\012");
		608
		609	An AnyEvent::Handle receiver would simply use the C<json> read type and
		610	rely on the fact that the newline will be skipped as leading whitespace:
		611
		612	$handle->push_read (json => sub { my $array = $_[1]; ... });
		613
		614	Other languages could read single lines terminated by a newline and pass
		615	this line into their JSON decoder of choice.
		616
		617	=cut
		618
		619	register_write_type json => sub {
		620	my ($self, $ref) = @_;
		621
		622	require JSON;
		623
		624	$self->{json} ? $self->{json}->encode ($ref)
		625	: JSON::encode_json ($ref)
		626	};
		627
		628	=item storable => $reference
		629
		630	Freezes the given reference using L<Storable> and writes it to the
		631	handle. Uses the C<nfreeze> format.
		632
		633	=cut
		634
		635	register_write_type storable => sub {
		636	my ($self, $ref) = @_;
		637
		638	require Storable;
		639
		640	pack "w/a*", Storable::nfreeze ($ref)
		641	};
		642
		643	=back
		644
		645	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		646
		647	This function (not method) lets you add your own types to C<push_write>.
		648	Whenever the given C<type> is used, C<push_write> will invoke the code
		649	reference with the handle object and the remaining arguments.
		650
		651	The code reference is supposed to return a single octet string that will
		652	be appended to the write buffer.
		653
		654	Note that this is a function, and all types registered this way will be
		655	global, so try to use unique names.
		656
		657	=cut
		658
		659	#############################################################################
		660
		661	=back
		662
		663	=head2 READ QUEUE
		664
		665	AnyEvent::Handle manages two queues per handle, one for writing and one
		666	for reading.
		667
		668	The read queue is more complex than the write queue. It can be used in two
		669	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		670	a queue.
		671
		672	In the simple case, you just install an C<on_read> callback and whenever
		673	new data arrives, it will be called. You can then remove some data (if
		674	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
		675	leave the data there if you want to accumulate more (e.g. when only a
		676	partial message has been received so far).
		677
		678	In the more complex case, you want to queue multiple callbacks. In this
		679	case, AnyEvent::Handle will call the first queued callback each time new
		680	data arrives (also the first time it is queued) and removes it when it has
		681	done its job (see C<push_read>, below).
		682
		683	This way you can, for example, push three line-reads, followed by reading
		684	a chunk of data, and AnyEvent::Handle will execute them in order.
		685
		686	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		687	the specified number of bytes which give an XML datagram.
		688
		689	# in the default state, expect some header bytes
		690	$handle->on_read (sub {
		691	# some data is here, now queue the length-header-read (4 octets)
		692	shift->unshift_read (chunk => 4, sub {
		693	# header arrived, decode
		694	my $len = unpack "N", $_[1];
		695
		696	# now read the payload
		697	shift->unshift_read (chunk => $len, sub {
		698	my $xml = $_[1];
		699	# handle xml
		700	});
		701	});
		702	});
		703
		704	Example 2: Implement a client for a protocol that replies either with "OK"
		705	and another line or "ERROR" for the first request that is sent, and 64
		706	bytes for the second request. Due to the availability of a queue, we can
		707	just pipeline sending both requests and manipulate the queue as necessary
		708	in the callbacks.
		709
		710	When the first callback is called and sees an "OK" response, it will
		711	C<unshift> another line-read. This line-read will be queued I<before> the
		712	64-byte chunk callback.
		713
		714	# request one, returns either "OK + extra line" or "ERROR"
		715	$handle->push_write ("request 1\015\012");
		716
		717	# we expect "ERROR" or "OK" as response, so push a line read
		718	$handle->push_read (line => sub {
		719	# if we got an "OK", we have to _prepend_ another line,
		720	# so it will be read before the second request reads its 64 bytes
		721	# which are already in the queue when this callback is called
		722	# we don't do this in case we got an error
		723	if ($_[1] eq "OK") {
49	on_readline => sub {	724	$_[0]->unshift_read (line => sub {
50	my ($ae_fh, @lines) = @_;	725	my $response = $_[1];
51	for (@lines) {	726	...
52	chomp;	727	});
53	print "Line: $_";	728	}
		729	});
		730
		731	# request two, simply returns 64 octets
		732	$handle->push_write ("request 2\015\012");
		733
		734	# simply read 64 bytes, always
		735	$handle->push_read (chunk => 64, sub {
		736	my $response = $_[1];
		737	...
		738	});
		739
		740	=over 4
		741
		742	=cut
		743
		744	sub _drain_rbuf {
		745	my ($self) = @_;
		746
		747	local $self->{_in_drain} = 1;
		748
		749	if (
		750	defined $self->{rbuf_max}
		751	&& $self->{rbuf_max} < length $self->{rbuf}
		752	) {
		753	$self->_error (&Errno::ENOSPC, 1), return;
		754	}
		755
		756	while () {
		757	my $len = length $self->{rbuf};
		758
		759	if (my $cb = shift @{ $self->{_queue} }) {
		760	unless ($cb->($self)) {
		761	if ($self->{_eof}) {
		762	# no progress can be made (not enough data and no data forthcoming)
		763	$self->_error (&Errno::EPIPE, 1), return;
54	}	764	}
		765
		766	unshift @{ $self->{_queue} }, $cb;
		767	last;
55	}	768	}
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}) {	769	} elsif ($self->{on_read}) {
121	$self->readlines ($self->{on_readline});	770	last unless $len;
122		771
		772	$self->{on_read}($self);
		773
		774	if (
		775	$len == length $self->{rbuf} # if no data has been consumed
		776	&& !@{ $self->{_queue} } # and the queue is still empty
		777	&& $self->{on_read} # but we still have on_read
		778	) {
		779	# no further data will arrive
		780	# so no progress can be made
		781	$self->_error (&Errno::EPIPE, 1), return
		782	if $self->{_eof};
		783
		784	last; # more data might arrive
		785	}
		786	} else {
		787	# read side becomes idle
		788	delete $self->{_rw};
		789	last;
		790	}
		791	}
		792
123	} elsif ($self->{on_eof}) {	793	if ($self->{_eof}) {
124	$self->on_eof ($self->{on_eof});
125
126	} elsif ($self->{on_error}) {	794	if ($self->{on_eof}) {
127	$self->on_eof ($self->{on_error});	795	$self->{on_eof}($self)
		796	} else {
		797	$self->_error (0, 1);
		798	}
128	}	799	}
129		800
130	return $self	801	# may need to restart read watcher
		802	unless ($self->{_rw}) {
		803	$self->start_read
		804	if $self->{on_read} || @{ $self->{_queue} };
		805	}
131	}	806	}
132		807
133	=item B<fh>	808	=item $handle->on_read ($cb)
134		809
135	This method returns the filehandle of the L<AnyEvent::Handle> object.	810	This replaces the currently set C<on_read> callback, or clears it (when
136		811	the new callback is C<undef>). See the description of C<on_read> in the
137	=cut	812	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		813
149	=cut	814	=cut
150		815
151	sub on_read {	816	sub on_read {
152	my ($self, $cb) = @_;	817	my ($self, $cb) = @_;
		818
153	$self->{on_read} = $cb;	819	$self->{on_read} = $cb;
		820	$self->_drain_rbuf if $cb && !$self->{_in_drain};
		821	}
154		822
155	unless (defined $self->{on_read}) {	823	=item $handle->rbuf
156	delete $self->{on_read_w};	824
		825	Returns the read buffer (as a modifiable lvalue).
		826
		827	You can access the read buffer directly as the C<< ->{rbuf} >> member, if
		828	you want.
		829
		830	NOTE: The read buffer should only be used or modified if the C<on_read>,
		831	C<push_read> or C<unshift_read> methods are used. The other read methods
		832	automatically manage the read buffer.
		833
		834	=cut
		835
		836	sub rbuf : lvalue {
		837	$_[0]{rbuf}
		838	}
		839
		840	=item $handle->push_read ($cb)
		841
		842	=item $handle->unshift_read ($cb)
		843
		844	Append the given callback to the end of the queue (C<push_read>) or
		845	prepend it (C<unshift_read>).
		846
		847	The callback is called each time some additional read data arrives.
		848
		849	It must check whether enough data is in the read buffer already.
		850
		851	If not enough data is available, it must return the empty list or a false
		852	value, in which case it will be called repeatedly until enough data is
		853	available (or an error condition is detected).
		854
		855	If enough data was available, then the callback must remove all data it is
		856	interested in (which can be none at all) and return a true value. After returning
		857	true, it will be removed from the queue.
		858
		859	=cut
		860
		861	our %RH;
		862
		863	sub register_read_type($$) {
		864	$RH{$_[0]} = $_[1];
		865	}
		866
		867	sub push_read {
		868	my $self = shift;
		869	my $cb = pop;
		870
		871	if (@_) {
		872	my $type = shift;
		873
		874	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		875	->($self, $cb, @_);
		876	}
		877
		878	push @{ $self->{_queue} }, $cb;
		879	$self->_drain_rbuf unless $self->{_in_drain};
		880	}
		881
		882	sub unshift_read {
		883	my $self = shift;
		884	my $cb = pop;
		885
		886	if (@_) {
		887	my $type = shift;
		888
		889	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		890	->($self, $cb, @_);
		891	}
		892
		893
		894	unshift @{ $self->{_queue} }, $cb;
		895	$self->_drain_rbuf unless $self->{_in_drain};
		896	}
		897
		898	=item $handle->push_read (type => @args, $cb)
		899
		900	=item $handle->unshift_read (type => @args, $cb)
		901
		902	Instead of providing a callback that parses the data itself you can chose
		903	between a number of predefined parsing formats, for chunks of data, lines
		904	etc.
		905
		906	Predefined types are (if you have ideas for additional types, feel free to
		907	drop by and tell us):
		908
		909	=over 4
		910
		911	=item chunk => $octets, $cb->($handle, $data)
		912
		913	Invoke the callback only once C<$octets> bytes have been read. Pass the
		914	data read to the callback. The callback will never be called with less
		915	data.
		916
		917	Example: read 2 bytes.
		918
		919	$handle->push_read (chunk => 2, sub {
		920	warn "yay ", unpack "H*", $_[1];
		921	});
		922
		923	=cut
		924
		925	register_read_type chunk => sub {
		926	my ($self, $cb, $len) = @_;
		927
		928	sub {
		929	$len <= length $_[0]{rbuf} or return;
		930	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
		931	1
		932	}
		933	};
		934
		935	=item line => [$eol, ]$cb->($handle, $line, $eol)
		936
		937	The callback will be called only once a full line (including the end of
		938	line marker, C<$eol>) has been read. This line (excluding the end of line
		939	marker) will be passed to the callback as second argument (C<$line>), and
		940	the end of line marker as the third argument (C<$eol>).
		941
		942	The end of line marker, C<$eol>, can be either a string, in which case it
		943	will be interpreted as a fixed record end marker, or it can be a regex
		944	object (e.g. created by C<qr>), in which case it is interpreted as a
		945	regular expression.
		946
		947	The end of line marker argument C<$eol> is optional, if it is missing (NOT
		948	undef), then C<qr|\015?\012|> is used (which is good for most internet
		949	protocols).
		950
		951	Partial lines at the end of the stream will never be returned, as they are
		952	not marked by the end of line marker.
		953
		954	=cut
		955
		956	register_read_type line => sub {
		957	my ($self, $cb, $eol) = @_;
		958
		959	if (@_ < 3) {
		960	# this is more than twice as fast as the generic code below
		961	sub {
		962	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		963
		964	$cb->($_[0], $1, $2);
		965	1
		966	}
		967	} else {
		968	$eol = quotemeta $eol unless ref $eol;
		969	$eol = qr|^(.*?)($eol)|s;
		970
		971	sub {
		972	$_[0]{rbuf} =~ s/$eol// or return;
		973
		974	$cb->($_[0], $1, $2);
		975	1
		976	}
		977	}
		978	};
		979
		980	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		981
		982	Makes a regex match against the regex object C<$accept> and returns
		983	everything up to and including the match.
		984
		985	Example: read a single line terminated by '\n'.
		986
		987	$handle->push_read (regex => qr<\n>, sub { ... });
		988
		989	If C<$reject> is given and not undef, then it determines when the data is
		990	to be rejected: it is matched against the data when the C<$accept> regex
		991	does not match and generates an C<EBADMSG> error when it matches. This is
		992	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		993	receive buffer overflow).
		994
		995	Example: expect a single decimal number followed by whitespace, reject
		996	anything else (not the use of an anchor).
		997
		998	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		999
		1000	If C<$skip> is given and not C<undef>, then it will be matched against
		1001	the receive buffer when neither C<$accept> nor C<$reject> match,
		1002	and everything preceding and including the match will be accepted
		1003	unconditionally. This is useful to skip large amounts of data that you
		1004	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1005	have to start matching from the beginning. This is purely an optimisation
		1006	and is usually worth only when you expect more than a few kilobytes.
		1007
		1008	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1009	expect the header to be very large (it isn't in practise, but...), we use
		1010	a skip regex to skip initial portions. The skip regex is tricky in that
		1011	it only accepts something not ending in either \015 or \012, as these are
		1012	required for the accept regex.
		1013
		1014	$handle->push_read (regex =>
		1015	qr<\015\012\015\012>,
		1016	undef, # no reject
		1017	qr<^.*[^\015\012]>,
		1018	sub { ... });
		1019
		1020	=cut
		1021
		1022	register_read_type regex => sub {
		1023	my ($self, $cb, $accept, $reject, $skip) = @_;
		1024
		1025	my $data;
		1026	my $rbuf = \$self->{rbuf};
		1027
		1028	sub {
		1029	# accept
		1030	if ($$rbuf =~ $accept) {
		1031	$data .= substr $$rbuf, 0, $+[0], "";
		1032	$cb->($self, $data);
157	return;	1033	return 1;
		1034	}
		1035
		1036	# reject
		1037	if ($reject && $$rbuf =~ $reject) {
		1038	$self->_error (&Errno::EBADMSG);
		1039	}
		1040
		1041	# skip
		1042	if ($skip && $$rbuf =~ $skip) {
		1043	$data .= substr $$rbuf, 0, $+[0], "";
		1044	}
		1045
		1046	()
158	}	1047	}
159		1048	};
160	$self->{on_read_w} =	1049
161	AnyEvent->io (poll => 'r', fh => $self->{fh}, cb => sub {	1050	=item netstring => $cb->($handle, $string)
162	#d# warn "READ:[$self->{read_size}] $self->{read_block_size} : ".length ($self->{rbuf})."\n";	1051
163	my $rbuf_len = length $self->{rbuf};	1052	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
164	my $l;	1053
165	if (defined $self->{read_size}) {	1054	Throws an error with C<$!> set to EBADMSG on format violations.
166	$l = sysread $self->{fh}, $self->{rbuf},	1055
167	($self->{read_size} - $rbuf_len), $rbuf_len;	1056	=cut
168	} else {	1057
169	$l = sysread $self->{fh}, $self->{rbuf}, $self->{read_block_size}, $rbuf_len;	1058	register_read_type netstring => sub {
		1059	my ($self, $cb) = @_;
		1060
		1061	sub {
		1062	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1063	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1064	$self->_error (&Errno::EBADMSG);
170	}	1065	}
171	#d# warn "READL $l [$self->{rbuf}]\n";	1066	return;
		1067	}
172		1068
173	if (not defined $l) {	1069	my $len = $1;
174	return if $! == EAGAIN || $! == EINTR;
175	$self->{on_error}->($self) if $self->{on_error};
176	delete $self->{on_read_w};
177		1070
178	} elsif ($l == 0) {	1071	$self->unshift_read (chunk => $len, sub {
179	$self->{on_eof}->($self) if $self->{on_eof};	1072	my $string = $_[1];
180	delete $self->{on_read_w};	1073	$_[0]->unshift_read (chunk => 1, sub {
181		1074	if ($_[1] eq ",") {
		1075	$cb->($_[0], $string);
182	} else {	1076	} else {
183	$self->{on_read}->($self);	1077	$self->_error (&Errno::EBADMSG);
		1078	}
		1079	});
		1080	});
		1081
		1082	1
		1083	}
		1084	};
		1085
		1086	=item packstring => $format, $cb->($handle, $string)
		1087
		1088	An octet string prefixed with an encoded length. The encoding C<$format>
		1089	uses the same format as a Perl C<pack> format, but must specify a single
		1090	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1091	optional C<!>, C<< < >> or C<< > >> modifier).
		1092
		1093	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.
		1094
		1095	Example: read a block of data prefixed by its length in BER-encoded
		1096	format (very efficient).
		1097
		1098	$handle->push_read (packstring => "w", sub {
		1099	my ($handle, $data) = @_;
		1100	});
		1101
		1102	=cut
		1103
		1104	register_read_type packstring => sub {
		1105	my ($self, $cb, $format) = @_;
		1106
		1107	sub {
		1108	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1109	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1110	or return;
		1111
		1112	$format = length pack $format, $len;
		1113
		1114	# bypass unshift if we already have the remaining chunk
		1115	if ($format + $len <= length $_[0]{rbuf}) {
		1116	my $data = substr $_[0]{rbuf}, $format, $len;
		1117	substr $_[0]{rbuf}, 0, $format + $len, "";
		1118	$cb->($_[0], $data);
		1119	} else {
		1120	# remove prefix
		1121	substr $_[0]{rbuf}, 0, $format, "";
		1122
		1123	# read remaining chunk
		1124	$_[0]->unshift_read (chunk => $len, $cb);
		1125	}
		1126
		1127	1
		1128	}
		1129	};
		1130
		1131	=item json => $cb->($handle, $hash_or_arrayref)
		1132
		1133	Reads a JSON object or array, decodes it and passes it to the callback.
		1134
		1135	If a C<json> object was passed to the constructor, then that will be used
		1136	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1137
		1138	This read type uses the incremental parser available with JSON version
		1139	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1140	dependency on your own: this module will load the JSON module, but
		1141	AnyEvent does not depend on it itself.
		1142
		1143	Since JSON texts are fully self-delimiting, the C<json> read and write
		1144	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1145	the C<json> write type description, above, for an actual example.
		1146
		1147	=cut
		1148
		1149	register_read_type json => sub {
		1150	my ($self, $cb) = @_;
		1151
		1152	require JSON;
		1153
		1154	my $data;
		1155	my $rbuf = \$self->{rbuf};
		1156
		1157	my $json = $self->{json} ||= JSON->new->utf8;
		1158
		1159	sub {
		1160	my $ref = $json->incr_parse ($self->{rbuf});
		1161
		1162	if ($ref) {
		1163	$self->{rbuf} = $json->incr_text;
		1164	$json->incr_text = "";
		1165	$cb->($self, $ref);
		1166
		1167	1
		1168	} else {
		1169	$self->{rbuf} = "";
		1170	()
		1171	}
		1172	}
		1173	};
		1174
		1175	=item storable => $cb->($handle, $ref)
		1176
		1177	Deserialises a L<Storable> frozen representation as written by the
		1178	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1179	data).
		1180
		1181	Raises C<EBADMSG> error if the data could not be decoded.
		1182
		1183	=cut
		1184
		1185	register_read_type storable => sub {
		1186	my ($self, $cb) = @_;
		1187
		1188	require Storable;
		1189
		1190	sub {
		1191	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1192	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1193	or return;
		1194
		1195	my $format = length pack "w", $len;
		1196
		1197	# bypass unshift if we already have the remaining chunk
		1198	if ($format + $len <= length $_[0]{rbuf}) {
		1199	my $data = substr $_[0]{rbuf}, $format, $len;
		1200	substr $_[0]{rbuf}, 0, $format + $len, "";
		1201	$cb->($_[0], Storable::thaw ($data));
		1202	} else {
		1203	# remove prefix
		1204	substr $_[0]{rbuf}, 0, $format, "";
		1205
		1206	# read remaining chunk
		1207	$_[0]->unshift_read (chunk => $len, sub {
		1208	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1209	$cb->($_[0], $ref);
		1210	} else {
		1211	$self->_error (&Errno::EBADMSG);
		1212	}
		1213	});
		1214	}
		1215
		1216	1
		1217	}
		1218	};
		1219
		1220	=back
		1221
		1222	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1223
		1224	This function (not method) lets you add your own types to C<push_read>.
		1225
		1226	Whenever the given C<type> is used, C<push_read> will invoke the code
		1227	reference with the handle object, the callback and the remaining
		1228	arguments.
		1229
		1230	The code reference is supposed to return a callback (usually a closure)
		1231	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1232
		1233	It should invoke the passed callback when it is done reading (remember to
		1234	pass C<$handle> as first argument as all other callbacks do that).
		1235
		1236	Note that this is a function, and all types registered this way will be
		1237	global, so try to use unique names.
		1238
		1239	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1240	search for C<register_read_type>)).
		1241
		1242	=item $handle->stop_read
		1243
		1244	=item $handle->start_read
		1245
		1246	In rare cases you actually do not want to read anything from the
		1247	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
		1248	any queued callbacks will be executed then. To start reading again, call
		1249	C<start_read>.
		1250
		1251	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1252	you change the C<on_read> callback or push/unshift a read callback, and it
		1253	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1254	there are any read requests in the queue.
		1255
		1256	=cut
		1257
		1258	sub stop_read {
		1259	my ($self) = @_;
		1260
		1261	delete $self->{_rw};
		1262	}
		1263
		1264	sub start_read {
		1265	my ($self) = @_;
		1266
		1267	unless ($self->{_rw} || $self->{_eof}) {
		1268	Scalar::Util::weaken $self;
		1269
		1270	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
		1271	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
		1272	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
		1273
		1274	if ($len > 0) {
		1275	$self->{_activity} = AnyEvent->now;
		1276
		1277	$self->{filter_r}
		1278	? $self->{filter_r}($self, $rbuf)
		1279	: $self->{_in_drain} || $self->_drain_rbuf;
		1280
		1281	} elsif (defined $len) {
		1282	delete $self->{_rw};
		1283	$self->{_eof} = 1;
		1284	$self->_drain_rbuf unless $self->{_in_drain};
		1285
		1286	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		1287	return $self->_error ($!, 1);
184	}	1288	}
185	});	1289	});
		1290	}
186	}	1291	}
187		1292
188	=item B<on_error ($callback)>	1293	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) = @_;	1294	my ($self) = @_;
240		1295
241	$self->{read_cb} = $cb;	1296	my $buf;
242	my $old_blk_size = $self->{read_block_size};
243	$self->{read_block_size} = $len;
244		1297
245	$self->on_read (sub {	1298	if (length $self->{_tls_wbuf}) {
246	#d# warn "OFOFO $len || ".length($_[0]->{rbuf})."||\n";	1299	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
247		1300	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	}	1301	}
253	});	1302	}
254	}
255		1303
256	=item B<readlines ($callback)>	1304	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
257		1305	$self->{wbuf} .= $buf;
258	=item B<readlines ($sep, $callback)>	1306	$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	}	1307	}
281		1308
282	my $sep_len = length $sep;	1309	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
283		1310	if (length $buf) {
284	$self->{on_readline} = $cb;	1311	$self->{rbuf} .= $buf;
285		1312	$self->_drain_rbuf unless $self->{_in_drain};
286	$self->on_read (sub {	1313	} else {
287	my @lines;	1314	# let's treat SSL-eof as we treat normal EOF
288	my $rb = \$_[0]->{rbuf};	1315	$self->{_eof} = 1;
289	my $pos;	1316	$self->_shutdown;
290	while (($pos = index ($$rb, $sep)) >= 0) {	1317	return;
291	push @lines, substr $$rb, 0, $pos + $sep_len, '';
292	}	1318	}
293	$self->{on_readline}->($_[0], @lines);	1319	}
		1320
		1321	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1322
		1323	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1324	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1325	return $self->_error ($!, 1);
		1326	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1327	return $self->_error (&Errno::EIO, 1);
		1328	}
		1329
		1330	# all others are fine for our purposes
		1331	}
		1332	}
		1333
		1334	=item $handle->starttls ($tls[, $tls_ctx])
		1335
		1336	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1337	object is created, you can also do that at a later time by calling
		1338	C<starttls>.
		1339
		1340	The first argument is the same as the C<tls> constructor argument (either
		1341	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1342
		1343	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1344	used when AnyEvent::Handle has to create its own TLS connection object.
		1345
		1346	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1347	call and can be used or changed to your liking. Note that the handshake
		1348	might have already started when this function returns.
		1349
		1350	=cut
		1351
		1352	sub starttls {
		1353	my ($self, $ssl, $ctx) = @_;
		1354
		1355	$self->stoptls;
		1356
		1357	if ($ssl eq "accept") {
		1358	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1359	Net::SSLeay::set_accept_state ($ssl);
		1360	} elsif ($ssl eq "connect") {
		1361	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1362	Net::SSLeay::set_connect_state ($ssl);
		1363	}
		1364
		1365	$self->{tls} = $ssl;
		1366
		1367	# basically, this is deep magic (because SSL_read should have the same issues)
		1368	# but the openssl maintainers basically said: "trust us, it just works".
		1369	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1370	# and mismaintained ssleay-module doesn't even offer them).
		1371	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1372	Net::SSLeay::CTX_set_mode ($self->{tls},
		1373	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1374	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1375
		1376	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1377	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1378
		1379	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1380
		1381	$self->{filter_w} = sub {
		1382	$_[0]{_tls_wbuf} .= ${$_[1]};
		1383	&_dotls;
294	});	1384	};
		1385	$self->{filter_r} = sub {
		1386	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
		1387	&_dotls;
		1388	};
295	}	1389	}
296		1390
297	=item B<write ($data)>	1391	=item $handle->stoptls
298		1392
299	=item B<write ($callback)>	1393	Destroys the SSL connection, if any. Partial read or write data will be
		1394	lost.
300		1395
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	1396	=cut
308		1397
309	sub write {	1398	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) = @_;	1399	my ($self) = @_;
318		1400
319	if ($self->{write_w}) {	1401	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		1402
329	my $wba = shift @{$self->{write_bufs}}	1403	delete $self->{_rbio};
330	or return;	1404	delete $self->{_wbio};
		1405	delete $self->{_tls_wbuf};
		1406	delete $self->{filter_r};
		1407	delete $self->{filter_w};
		1408	}
331		1409
332	unless (defined $wba->[0]) {	1410	sub DESTROY {
333	$wba->[1]->($self) if $wba->[1];	1411	my $self = shift;
334	$self->_check_writer;
335	return;
336	}
337		1412
338	$self->{wbuf} = $wba->[0];	1413	$self->stoptls;
339	$self->{write_cb} = $wba->[1];
340		1414
341	$self->{write_w} =	1415	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
342	AnyEvent->io (poll => 'w', fh => $self->{fh}, cb => sub {	1416
		1417	if ($linger && length $self->{wbuf}) {
		1418	my $fh = delete $self->{fh};
		1419	my $wbuf = delete $self->{wbuf};
		1420
		1421	my @linger;
		1422
		1423	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
343	my $l = syswrite $self->{fh}, $self->{wbuf}, length $self->{wbuf};	1424	my $len = syswrite $fh, $wbuf, length $wbuf;
344		1425
345	if (not defined $l) {	1426	if ($len > 0) {
346	return if $! == EAGAIN || $! == EINTR;	1427	substr $wbuf, 0, $len, "";
347	delete $self->{write_w};
348	$self->{on_error}->($self) if $self->{on_error};
349
350	} else {	1428	} else {
351	substr $self->{wbuf}, 0, $l, '';	1429	@linger = (); # end
352
353	if (length ($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	}	1430	}
363	});	1431	});
		1432	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1433	@linger = ();
		1434	});
		1435	}
		1436	}
		1437
		1438	=item AnyEvent::Handle::TLS_CTX
		1439
		1440	This function creates and returns the Net::SSLeay::CTX object used by
		1441	default for TLS mode.
		1442
		1443	The context is created like this:
		1444
		1445	Net::SSLeay::load_error_strings;
		1446	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1447	Net::SSLeay::randomize;
		1448
		1449	my $CTX = Net::SSLeay::CTX_new;
		1450
		1451	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1452
		1453	=cut
		1454
		1455	our $TLS_CTX;
		1456
		1457	sub TLS_CTX() {
		1458	$TLS_CTX || do {
		1459	require Net::SSLeay;
		1460
		1461	Net::SSLeay::load_error_strings ();
		1462	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1463	Net::SSLeay::randomize ();
		1464
		1465	$TLS_CTX = Net::SSLeay::CTX_new ();
		1466
		1467	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1468
		1469	$TLS_CTX
		1470	}
364	}	1471	}
365		1472
366	=back	1473	=back
367		1474
		1475	=head1 SUBCLASSING AnyEvent::Handle
		1476
		1477	In many cases, you might want to subclass AnyEvent::Handle.
		1478
		1479	To make this easier, a given version of AnyEvent::Handle uses these
		1480	conventions:
		1481
		1482	=over 4
		1483
		1484	=item * all constructor arguments become object members.
		1485
		1486	At least initially, when you pass a C<tls>-argument to the constructor it
		1487	will end up in C<< $handle->{tls} >>. Those members might be changed or
		1488	mutated later on (for example C<tls> will hold the TLS connection object).
		1489
		1490	=item * other object member names are prefixed with an C<_>.
		1491
		1492	All object members not explicitly documented (internal use) are prefixed
		1493	with an underscore character, so the remaining non-C<_>-namespace is free
		1494	for use for subclasses.
		1495
		1496	=item * all members not documented here and not prefixed with an underscore
		1497	are free to use in subclasses.
		1498
		1499	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1500	member variables, but thats just life, at least it is documented.
		1501
		1502	=back
		1503
368	=head1 AUTHOR	1504	=head1 AUTHOR
369		1505
370	Robin Redeker, C<< <elmex at ta-sa.org> >>	1506	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
371		1507
372	=cut	1508	=cut
373		1509
374	1; # End of AnyEvent::Handle	1510	1; # End of AnyEvent::Handle

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