ViewVC Help

View File | Revision Log | Show Annotations | Download File

/cvs/AnyEvent/lib/AnyEvent/Handle.pm

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.6 by elmex, Mon Apr 28 09:27:47 2008 UTC vs.
Revision 1.42 by root, Tue May 27 06:23:15 2008 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	no warnings;	3	no warnings;
4	use strict;	4	use strict;
5		5
6	use AnyEvent;	6	use AnyEvent ();
7	use IO::Handle;	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		8	use Scalar::Util ();
		9	use Carp ();
		10	use Fcntl ();
8	use Errno qw/EAGAIN EINTR/;	11	use Errno qw/EAGAIN EINTR/;
9		12
10	=head1 NAME	13	=head1 NAME
11		14
12	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
13		16
14	=head1 VERSION
15
16	Version 0.01
17
18	=cut	17	=cut
19		18
20	our $VERSION = '0.01';	19	our $VERSION = '0.04';
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	},
49	on_readline => sub {	34	);
		35
		36	# send some request line
		37	$handle->push_write ("getinfo\015\012");
		38
		39	# read the response line
		40	$handle->push_read (line => sub {
50	my ($ae_fh, @lines) = @_;	41	my ($handle, $line) = @_;
51	for (@lines) {	42	warn "read line <$line>\n";
52	chomp;	43	$cv->send;
53	print "Line: $_";	44	});
		45
		46	$cv->recv;
		47
		48	=head1 DESCRIPTION
		49
		50	This module is a helper module to make it easier to do event-based I/O on
		51	filehandles. For utility functions for doing non-blocking connects and accepts
		52	on sockets see L<AnyEvent::Util>.
		53
		54	In the following, when the documentation refers to of "bytes" then this
		55	means characters. As sysread and syswrite are used for all I/O, their
		56	treatment of characters applies to this module as well.
		57
		58	All callbacks will be invoked with the handle object as their first
		59	argument.
		60
		61	=head1 METHODS
		62
		63	=over 4
		64
		65	=item B<new (%args)>
		66
		67	The constructor supports these arguments (all as key => value pairs).
		68
		69	=over 4
		70
		71	=item fh => $filehandle [MANDATORY]
		72
		73	The filehandle this L<AnyEvent::Handle> object will operate on.
		74
		75	NOTE: The filehandle will be set to non-blocking (using
		76	AnyEvent::Util::fh_nonblocking).
		77
		78	=item on_eof => $cb->($handle)
		79
		80	Set the callback to be called on EOF.
		81
		82	While not mandatory, it is highly recommended to set an eof callback,
		83	otherwise you might end up with a closed socket while you are still
		84	waiting for data.
		85
		86	=item on_error => $cb->($handle)
		87
		88	This is the fatal error callback, that is called when, well, a fatal error
		89	occurs, such as not being able to resolve the hostname, failure to connect
		90	or a read error.
		91
		92	The object will not be in a usable state when this callback has been
		93	called.
		94
		95	On callback entrance, the value of C<$!> contains the operating system
		96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).
		97
		98	The callback should throw an exception. If it returns, then
		99	AnyEvent::Handle will C<croak> for you.
		100
		101	While not mandatory, it is I<highly> recommended to set this callback, as
		102	you will not be notified of errors otherwise. The default simply calls
		103	die.
		104
		105	=item on_read => $cb->($handle)
		106
		107	This sets the default read callback, which is called when data arrives
		108	and no read request is in the queue.
		109
		110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
		111	method or access the C<$handle->{rbuf}> member directly.
		112
		113	When an EOF condition is detected then AnyEvent::Handle will first try to
		114	feed all the remaining data to the queued callbacks and C<on_read> before
		115	calling the C<on_eof> callback. If no progress can be made, then a fatal
		116	error will be raised (with C<$!> set to C<EPIPE>).
		117
		118	=item on_drain => $cb->($handle)
		119
		120	This sets the callback that is called when the write buffer becomes empty
		121	(or when the callback is set and the buffer is empty already).
		122
		123	To append to the write buffer, use the C<< ->push_write >> method.
		124
		125	=item rbuf_max => <bytes>
		126
		127	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		128	when the read buffer ever (strictly) exceeds this size. This is useful to
		129	avoid denial-of-service attacks.
		130
		131	For example, a server accepting connections from untrusted sources should
		132	be configured to accept only so-and-so much data that it cannot act on
		133	(for example, when expecting a line, an attacker could send an unlimited
		134	amount of data without a callback ever being called as long as the line
		135	isn't finished).
		136
		137	=item read_size => <bytes>
		138
		139	The default read block size (the amount of bytes this module will try to read
		140	on each [loop iteration). Default: C<4096>.
		141
		142	=item low_water_mark => <bytes>
		143
		144	Sets the amount of bytes (default: C<0>) that make up an "empty" write
		145	buffer: If the write reaches this size or gets even samller it is
		146	considered empty.
		147
		148	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
		149
		150	When this parameter is given, it enables TLS (SSL) mode, that means it
		151	will start making tls handshake and will transparently encrypt/decrypt
		152	data.
		153
		154	TLS mode requires Net::SSLeay to be installed (it will be loaded
		155	automatically when you try to create a TLS handle).
		156
		157	For the TLS server side, use C<accept>, and for the TLS client side of a
		158	connection, use C<connect> mode.
		159
		160	You can also provide your own TLS connection object, but you have
		161	to make sure that you call either C<Net::SSLeay::set_connect_state>
		162	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		163	AnyEvent::Handle.
		164
		165	See the C<starttls> method if you need to start TLs negotiation later.
		166
		167	=item tls_ctx => $ssl_ctx
		168
		169	Use the given Net::SSLeay::CTX object to create the new TLS connection
		170	(unless a connection object was specified directly). If this parameter is
		171	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		172
		173	=item json => JSON or JSON::XS object
		174
		175	This is the json coder object used by the C<json> read and write types.
		176
		177	If you don't supply it, then AnyEvent::Handle will create and use a
		178	suitable one, which will write and expect UTF-8 encoded JSON texts.
		179
		180	Note that you are responsible to depend on the JSON module if you want to
		181	use this functionality, as AnyEvent does not have a dependency itself.
		182
		183	=item filter_r => $cb
		184
		185	=item filter_w => $cb
		186
		187	These exist, but are undocumented at this time.
		188
		189	=back
		190
		191	=cut
		192
		193	sub new {
		194	my $class = shift;
		195
		196	my $self = bless { @_ }, $class;
		197
		198	$self->{fh} or Carp::croak "mandatory argument fh is missing";
		199
		200	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
		201
		202	if ($self->{tls}) {
		203	require Net::SSLeay;
		204	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
		205	}
		206
		207	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
		208	$self->on_error (delete $self->{on_error}) if $self->{on_error};
		209	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
		210	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
		211
		212	$self->start_read;
		213
		214	$self
		215	}
		216
		217	sub _shutdown {
		218	my ($self) = @_;
		219
		220	delete $self->{_rw};
		221	delete $self->{_ww};
		222	delete $self->{fh};
		223	}
		224
		225	sub error {
		226	my ($self) = @_;
		227
		228	{
		229	local $!;
		230	$self->_shutdown;
		231	}
		232
		233	$self->{on_error}($self)
		234	if $self->{on_error};
		235
		236	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";
		237	}
		238
		239	=item $fh = $handle->fh
		240
		241	This method returns the file handle of the L<AnyEvent::Handle> object.
		242
		243	=cut
		244
		245	sub fh { $_[0]{fh} }
		246
		247	=item $handle->on_error ($cb)
		248
		249	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
		250
		251	=cut
		252
		253	sub on_error {
		254	$_[0]{on_error} = $_[1];
		255	}
		256
		257	=item $handle->on_eof ($cb)
		258
		259	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
		260
		261	=cut
		262
		263	sub on_eof {
		264	$_[0]{on_eof} = $_[1];
		265	}
		266
		267	#############################################################################
		268
		269	=back
		270
		271	=head2 WRITE QUEUE
		272
		273	AnyEvent::Handle manages two queues per handle, one for writing and one
		274	for reading.
		275
		276	The write queue is very simple: you can add data to its end, and
		277	AnyEvent::Handle will automatically try to get rid of it for you.
		278
		279	When data could be written and the write buffer is shorter then the low
		280	water mark, the C<on_drain> callback will be invoked.
		281
		282	=over 4
		283
		284	=item $handle->on_drain ($cb)
		285
		286	Sets the C<on_drain> callback or clears it (see the description of
		287	C<on_drain> in the constructor).
		288
		289	=cut
		290
		291	sub on_drain {
		292	my ($self, $cb) = @_;
		293
		294	$self->{on_drain} = $cb;
		295
		296	$cb->($self)
		297	if $cb && $self->{low_water_mark} >= length $self->{wbuf};
		298	}
		299
		300	=item $handle->push_write ($data)
		301
		302	Queues the given scalar to be written. You can push as much data as you
		303	want (only limited by the available memory), as C<AnyEvent::Handle>
		304	buffers it independently of the kernel.
		305
		306	=cut
		307
		308	sub _drain_wbuf {
		309	my ($self) = @_;
		310
		311	if (!$self->{_ww} && length $self->{wbuf}) {
		312
		313	Scalar::Util::weaken $self;
		314
		315	my $cb = sub {
		316	my $len = syswrite $self->{fh}, $self->{wbuf};
		317
		318	if ($len >= 0) {
		319	substr $self->{wbuf}, 0, $len, "";
		320
		321	$self->{on_drain}($self)
		322	if $self->{low_water_mark} >= length $self->{wbuf}
		323	&& $self->{on_drain};
		324
		325	delete $self->{_ww} unless length $self->{wbuf};
		326	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		327	$self->error;
		328	}
		329	};
		330
		331	# try to write data immediately
		332	$cb->();
		333
		334	# if still data left in wbuf, we need to poll
		335	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
		336	if length $self->{wbuf};
		337	};
		338	}
		339
		340	our %WH;
		341
		342	sub register_write_type($$) {
		343	$WH{$_[0]} = $_[1];
		344	}
		345
		346	sub push_write {
		347	my $self = shift;
		348
		349	if (@_ > 1) {
		350	my $type = shift;
		351
		352	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		353	->($self, @_);
		354	}
		355
		356	if ($self->{filter_w}) {
		357	$self->{filter_w}->($self, \$_[0]);
		358	} else {
		359	$self->{wbuf} .= $_[0];
		360	$self->_drain_wbuf;
		361	}
		362	}
		363
		364	=item $handle->push_write (type => @args)
		365
		366	=item $handle->unshift_write (type => @args)
		367
		368	Instead of formatting your data yourself, you can also let this module do
		369	the job by specifying a type and type-specific arguments.
		370
		371	Predefined types are (if you have ideas for additional types, feel free to
		372	drop by and tell us):
		373
		374	=over 4
		375
		376	=item netstring => $string
		377
		378	Formats the given value as netstring
		379	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		380
		381	=back
		382
		383	=cut
		384
		385	register_write_type netstring => sub {
		386	my ($self, $string) = @_;
		387
		388	sprintf "%d:%s,", (length $string), $string
		389	};
		390
		391	=item json => $array_or_hashref
		392
		393	Encodes the given hash or array reference into a JSON object. Unless you
		394	provide your own JSON object, this means it will be encoded to JSON text
		395	in UTF-8.
		396
		397	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		398	one end of a handle and read them at the other end without using any
		399	additional framing.
		400
		401	The generated JSON text is guaranteed not to contain any newlines: While
		402	this module doesn't need delimiters after or between JSON texts to be
		403	able to read them, many other languages depend on that.
		404
		405	A simple RPC protocol that interoperates easily with others is to send
		406	JSON arrays (or objects, although arrays are usually the better choice as
		407	they mimic how function argument passing works) and a newline after each
		408	JSON text:
		409
		410	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		411	$handle->push_write ("\012");
		412
		413	An AnyEvent::Handle receiver would simply use the C<json> read type and
		414	rely on the fact that the newline will be skipped as leading whitespace:
		415
		416	$handle->push_read (json => sub { my $array = $_[1]; ... });
		417
		418	Other languages could read single lines terminated by a newline and pass
		419	this line into their JSON decoder of choice.
		420
		421	=cut
		422
		423	register_write_type json => sub {
		424	my ($self, $ref) = @_;
		425
		426	require JSON;
		427
		428	$self->{json} ? $self->{json}->encode ($ref)
		429	: JSON::encode_json ($ref)
		430	};
		431
		432	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		433
		434	This function (not method) lets you add your own types to C<push_write>.
		435	Whenever the given C<type> is used, C<push_write> will invoke the code
		436	reference with the handle object and the remaining arguments.
		437
		438	The code reference is supposed to return a single octet string that will
		439	be appended to the write buffer.
		440
		441	Note that this is a function, and all types registered this way will be
		442	global, so try to use unique names.
		443
		444	=cut
		445
		446	#############################################################################
		447
		448	=back
		449
		450	=head2 READ QUEUE
		451
		452	AnyEvent::Handle manages two queues per handle, one for writing and one
		453	for reading.
		454
		455	The read queue is more complex than the write queue. It can be used in two
		456	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		457	a queue.
		458
		459	In the simple case, you just install an C<on_read> callback and whenever
		460	new data arrives, it will be called. You can then remove some data (if
		461	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want
		462	or not.
		463
		464	In the more complex case, you want to queue multiple callbacks. In this
		465	case, AnyEvent::Handle will call the first queued callback each time new
		466	data arrives and removes it when it has done its job (see C<push_read>,
		467	below).
		468
		469	This way you can, for example, push three line-reads, followed by reading
		470	a chunk of data, and AnyEvent::Handle will execute them in order.
		471
		472	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		473	the specified number of bytes which give an XML datagram.
		474
		475	# in the default state, expect some header bytes
		476	$handle->on_read (sub {
		477	# some data is here, now queue the length-header-read (4 octets)
		478	shift->unshift_read_chunk (4, sub {
		479	# header arrived, decode
		480	my $len = unpack "N", $_[1];
		481
		482	# now read the payload
		483	shift->unshift_read_chunk ($len, sub {
		484	my $xml = $_[1];
		485	# handle xml
		486	});
		487	});
		488	});
		489
		490	Example 2: Implement a client for a protocol that replies either with
		491	"OK" and another line or "ERROR" for one request, and 64 bytes for the
		492	second request. Due tot he availability of a full queue, we can just
		493	pipeline sending both requests and manipulate the queue as necessary in
		494	the callbacks:
		495
		496	# request one
		497	$handle->push_write ("request 1\015\012");
		498
		499	# we expect "ERROR" or "OK" as response, so push a line read
		500	$handle->push_read_line (sub {
		501	# if we got an "OK", we have to _prepend_ another line,
		502	# so it will be read before the second request reads its 64 bytes
		503	# which are already in the queue when this callback is called
		504	# we don't do this in case we got an error
		505	if ($_[1] eq "OK") {
		506	$_[0]->unshift_read_line (sub {
		507	my $response = $_[1];
		508	...
		509	});
		510	}
		511	});
		512
		513	# request two
		514	$handle->push_write ("request 2\015\012");
		515
		516	# simply read 64 bytes, always
		517	$handle->push_read_chunk (64, sub {
		518	my $response = $_[1];
		519	...
		520	});
		521
		522	=over 4
		523
		524	=cut
		525
		526	sub _drain_rbuf {
		527	my ($self) = @_;
		528
		529	if (
		530	defined $self->{rbuf_max}
		531	&& $self->{rbuf_max} < length $self->{rbuf}
		532	) {
		533	$! = &Errno::ENOSPC;
		534	$self->error;
		535	}
		536
		537	return if $self->{in_drain};
		538	local $self->{in_drain} = 1;
		539
		540	while (my $len = length $self->{rbuf}) {
		541	no strict 'refs';
		542	if (my $cb = shift @{ $self->{_queue} }) {
		543	unless ($cb->($self)) {
		544	if ($self->{_eof}) {
		545	# no progress can be made (not enough data and no data forthcoming)
		546	$! = &Errno::EPIPE;
		547	$self->error;
54	}	548	}
		549
		550	unshift @{ $self->{_queue} }, $cb;
		551	return;
55	}	552	}
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}) {	553	} elsif ($self->{on_read}) {
121	$self->readlines ($self->{on_readline});	554	$self->{on_read}($self);
122		555
		556	if (
		557	$self->{_eof} # if no further data will arrive
		558	&& $len == length $self->{rbuf} # and no data has been consumed
		559	&& !@{ $self->{_queue} } # and the queue is still empty
		560	&& $self->{on_read} # and we still want to read data
		561	) {
		562	# then no progress can be made
		563	$! = &Errno::EPIPE;
		564	$self->error;
		565	}
		566	} else {
		567	# read side becomes idle
		568	delete $self->{_rw};
		569	return;
		570	}
		571	}
		572
123	} elsif ($self->{on_eof}) {	573	if ($self->{_eof}) {
124	$self->on_eof ($self->{on_eof});	574	$self->_shutdown;
125		575	$self->{on_eof}($self)
126	} elsif ($self->{on_error}) {	576	if $self->{on_eof};
127	$self->on_eof ($self->{on_error});
128	}	577	}
129
130	return $self
131	}	578	}
132		579
133	=item B<fh>	580	=item $handle->on_read ($cb)
134		581
135	This method returns the filehandle of the L<AnyEvent::Handle> object.	582	This replaces the currently set C<on_read> callback, or clears it (when
136		583	the new callback is C<undef>). See the description of C<on_read> in the
137	=cut	584	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		585
149	=cut	586	=cut
150		587
151	sub on_read {	588	sub on_read {
152	my ($self, $cb) = @_;	589	my ($self, $cb) = @_;
		590
153	$self->{on_read} = $cb;	591	$self->{on_read} = $cb;
		592	}
154		593
155	unless (defined $self->{on_read}) {	594	=item $handle->rbuf
156	delete $self->{on_read_w};	595
157	return;	596	Returns the read buffer (as a modifiable lvalue).
		597
		598	You can access the read buffer directly as the C<< ->{rbuf} >> member, if
		599	you want.
		600
		601	NOTE: The read buffer should only be used or modified if the C<on_read>,
		602	C<push_read> or C<unshift_read> methods are used. The other read methods
		603	automatically manage the read buffer.
		604
		605	=cut
		606
		607	sub rbuf : lvalue {
		608	$_[0]{rbuf}
		609	}
		610
		611	=item $handle->push_read ($cb)
		612
		613	=item $handle->unshift_read ($cb)
		614
		615	Append the given callback to the end of the queue (C<push_read>) or
		616	prepend it (C<unshift_read>).
		617
		618	The callback is called each time some additional read data arrives.
		619
		620	It must check whether enough data is in the read buffer already.
		621
		622	If not enough data is available, it must return the empty list or a false
		623	value, in which case it will be called repeatedly until enough data is
		624	available (or an error condition is detected).
		625
		626	If enough data was available, then the callback must remove all data it is
		627	interested in (which can be none at all) and return a true value. After returning
		628	true, it will be removed from the queue.
		629
		630	=cut
		631
		632	our %RH;
		633
		634	sub register_read_type($$) {
		635	$RH{$_[0]} = $_[1];
		636	}
		637
		638	sub push_read {
		639	my $self = shift;
		640	my $cb = pop;
		641
		642	if (@_) {
		643	my $type = shift;
		644
		645	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		646	->($self, $cb, @_);
		647	}
		648
		649	push @{ $self->{_queue} }, $cb;
		650	$self->_drain_rbuf;
		651	}
		652
		653	sub unshift_read {
		654	my $self = shift;
		655	my $cb = pop;
		656
		657	if (@_) {
		658	my $type = shift;
		659
		660	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		661	->($self, $cb, @_);
		662	}
		663
		664
		665	unshift @{ $self->{_queue} }, $cb;
		666	$self->_drain_rbuf;
		667	}
		668
		669	=item $handle->push_read (type => @args, $cb)
		670
		671	=item $handle->unshift_read (type => @args, $cb)
		672
		673	Instead of providing a callback that parses the data itself you can chose
		674	between a number of predefined parsing formats, for chunks of data, lines
		675	etc.
		676
		677	Predefined types are (if you have ideas for additional types, feel free to
		678	drop by and tell us):
		679
		680	=over 4
		681
		682	=item chunk => $octets, $cb->($handle, $data)
		683
		684	Invoke the callback only once C<$octets> bytes have been read. Pass the
		685	data read to the callback. The callback will never be called with less
		686	data.
		687
		688	Example: read 2 bytes.
		689
		690	$handle->push_read (chunk => 2, sub {
		691	warn "yay ", unpack "H*", $_[1];
158	}	692	});
159		693
160	$self->{on_read_w} =	694	=cut
161	AnyEvent->io (poll => 'r', fh => $self->{fh}, cb => sub {	695
162	#d# warn "READ:[$self->{read_size}] $self->{read_block_size} : ".length ($self->{rbuf})."\n";	696	register_read_type chunk => sub {
163	my $rbuf_len = length $self->{rbuf};	697	my ($self, $cb, $len) = @_;
164	my $l;	698
165	if (defined $self->{read_size}) {	699	sub {
166	$l = sysread $self->{fh}, $self->{rbuf},	700	$len <= length $_[0]{rbuf} or return;
167	($self->{read_size} - $rbuf_len), $rbuf_len;	701	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
168	} else {	702	1
169	$l = sysread $self->{fh}, $self->{rbuf}, $self->{read_block_size}, $rbuf_len;	703	}
		704	};
		705
		706	# compatibility with older API
		707	sub push_read_chunk {
		708	$_[0]->push_read (chunk => $_[1], $_[2]);
		709	}
		710
		711	sub unshift_read_chunk {
		712	$_[0]->unshift_read (chunk => $_[1], $_[2]);
		713	}
		714
		715	=item line => [$eol, ]$cb->($handle, $line, $eol)
		716
		717	The callback will be called only once a full line (including the end of
		718	line marker, C<$eol>) has been read. This line (excluding the end of line
		719	marker) will be passed to the callback as second argument (C<$line>), and
		720	the end of line marker as the third argument (C<$eol>).
		721
		722	The end of line marker, C<$eol>, can be either a string, in which case it
		723	will be interpreted as a fixed record end marker, or it can be a regex
		724	object (e.g. created by C<qr>), in which case it is interpreted as a
		725	regular expression.
		726
		727	The end of line marker argument C<$eol> is optional, if it is missing (NOT
		728	undef), then C<qr|\015?\012|> is used (which is good for most internet
		729	protocols).
		730
		731	Partial lines at the end of the stream will never be returned, as they are
		732	not marked by the end of line marker.
		733
		734	=cut
		735
		736	register_read_type line => sub {
		737	my ($self, $cb, $eol) = @_;
		738
		739	$eol = qr|(\015?\012)| if @_ < 3;
		740	$eol = quotemeta $eol unless ref $eol;
		741	$eol = qr|^(.*?)($eol)|s;
		742
		743	sub {
		744	$_[0]{rbuf} =~ s/$eol// or return;
		745
		746	$cb->($_[0], $1, $2);
		747	1
		748	}
		749	};
		750
		751	# compatibility with older API
		752	sub push_read_line {
		753	my $self = shift;
		754	$self->push_read (line => @_);
		755	}
		756
		757	sub unshift_read_line {
		758	my $self = shift;
		759	$self->unshift_read (line => @_);
		760	}
		761
		762	=item netstring => $cb->($handle, $string)
		763
		764	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		765
		766	Throws an error with C<$!> set to EBADMSG on format violations.
		767
		768	=cut
		769
		770	register_read_type netstring => sub {
		771	my ($self, $cb) = @_;
		772
		773	sub {
		774	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		775	if ($_[0]{rbuf} =~ /[^0-9]/) {
		776	$! = &Errno::EBADMSG;
		777	$self->error;
170	}	778	}
171	#d# warn "READL $l [$self->{rbuf}]\n";	779	return;
		780	}
172		781
173	if (not defined $l) {	782	my $len = $1;
174	return if $! == EAGAIN || $! == EINTR;
175	$self->{on_error}->($self) if $self->{on_error};
176	delete $self->{on_read_w};
177		783
178	} elsif ($l == 0) {	784	$self->unshift_read (chunk => $len, sub {
179	$self->{on_eof}->($self) if $self->{on_eof};	785	my $string = $_[1];
180	delete $self->{on_read_w};	786	$_[0]->unshift_read (chunk => 1, sub {
181		787	if ($_[1] eq ",") {
		788	$cb->($_[0], $string);
182	} else {	789	} else {
183	$self->{on_read}->($self);	790	$! = &Errno::EBADMSG;
		791	$self->error;
		792	}
		793	});
		794	});
		795
		796	1
		797	}
		798	};
		799
		800	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		801
		802	Makes a regex match against the regex object C<$accept> and returns
		803	everything up to and including the match.
		804
		805	Example: read a single line terminated by '\n'.
		806
		807	$handle->push_read (regex => qr<\n>, sub { ... });
		808
		809	If C<$reject> is given and not undef, then it determines when the data is
		810	to be rejected: it is matched against the data when the C<$accept> regex
		811	does not match and generates an C<EBADMSG> error when it matches. This is
		812	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		813	receive buffer overflow).
		814
		815	Example: expect a single decimal number followed by whitespace, reject
		816	anything else (not the use of an anchor).
		817
		818	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		819
		820	If C<$skip> is given and not C<undef>, then it will be matched against
		821	the receive buffer when neither C<$accept> nor C<$reject> match,
		822	and everything preceding and including the match will be accepted
		823	unconditionally. This is useful to skip large amounts of data that you
		824	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		825	have to start matching from the beginning. This is purely an optimisation
		826	and is usually worth only when you expect more than a few kilobytes.
		827
		828	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		829	expect the header to be very large (it isn't in practise, but...), we use
		830	a skip regex to skip initial portions. The skip regex is tricky in that
		831	it only accepts something not ending in either \015 or \012, as these are
		832	required for the accept regex.
		833
		834	$handle->push_read (regex =>
		835	qr<\015\012\015\012>,
		836	undef, # no reject
		837	qr<^.*[^\015\012]>,
		838	sub { ... });
		839
		840	=cut
		841
		842	register_read_type regex => sub {
		843	my ($self, $cb, $accept, $reject, $skip) = @_;
		844
		845	my $data;
		846	my $rbuf = \$self->{rbuf};
		847
		848	sub {
		849	# accept
		850	if ($$rbuf =~ $accept) {
		851	$data .= substr $$rbuf, 0, $+[0], "";
		852	$cb->($self, $data);
		853	return 1;
		854	}
		855
		856	# reject
		857	if ($reject && $$rbuf =~ $reject) {
		858	$! = &Errno::EBADMSG;
		859	$self->error;
		860	}
		861
		862	# skip
		863	if ($skip && $$rbuf =~ $skip) {
		864	$data .= substr $$rbuf, 0, $+[0], "";
		865	}
		866
		867	()
		868	}
		869	};
		870
		871	=item json => $cb->($handle, $hash_or_arrayref)
		872
		873	Reads a JSON object or array, decodes it and passes it to the callback.
		874
		875	If a C<json> object was passed to the constructor, then that will be used
		876	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		877
		878	This read type uses the incremental parser available with JSON version
		879	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		880	dependency on your own: this module will load the JSON module, but
		881	AnyEvent does not depend on it itself.
		882
		883	Since JSON texts are fully self-delimiting, the C<json> read and write
		884	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		885	the C<json> write type description, above, for an actual example.
		886
		887	=cut
		888
		889	register_read_type json => sub {
		890	my ($self, $cb, $accept, $reject, $skip) = @_;
		891
		892	require JSON;
		893
		894	my $data;
		895	my $rbuf = \$self->{rbuf};
		896
		897	my $json = $self->{json} ||= JSON->new->utf8;
		898
		899	sub {
		900	my $ref = $json->incr_parse ($self->{rbuf});
		901
		902	if ($ref) {
		903	$self->{rbuf} = $json->incr_text;
		904	$json->incr_text = "";
		905	$cb->($self, $ref);
		906
		907	1
		908	} else {
		909	$self->{rbuf} = "";
		910	()
		911	}
		912	}
		913	};
		914
		915	=back
		916
		917	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		918
		919	This function (not method) lets you add your own types to C<push_read>.
		920
		921	Whenever the given C<type> is used, C<push_read> will invoke the code
		922	reference with the handle object, the callback and the remaining
		923	arguments.
		924
		925	The code reference is supposed to return a callback (usually a closure)
		926	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		927
		928	It should invoke the passed callback when it is done reading (remember to
		929	pass C<$handle> as first argument as all other callbacks do that).
		930
		931	Note that this is a function, and all types registered this way will be
		932	global, so try to use unique names.
		933
		934	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		935	search for C<register_read_type>)).
		936
		937	=item $handle->stop_read
		938
		939	=item $handle->start_read
		940
		941	In rare cases you actually do not want to read anything from the
		942	socket. In this case you can call C<stop_read>. Neither C<on_read> no
		943	any queued callbacks will be executed then. To start reading again, call
		944	C<start_read>.
		945
		946	=cut
		947
		948	sub stop_read {
		949	my ($self) = @_;
		950
		951	delete $self->{_rw};
		952	}
		953
		954	sub start_read {
		955	my ($self) = @_;
		956
		957	unless ($self->{_rw} || $self->{_eof}) {
		958	Scalar::Util::weaken $self;
		959
		960	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
		961	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
		962	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
		963
		964	if ($len > 0) {
		965	$self->{filter_r}
		966	? $self->{filter_r}->($self, $rbuf)
		967	: $self->_drain_rbuf;
		968
		969	} elsif (defined $len) {
		970	delete $self->{_rw};
		971	$self->{_eof} = 1;
		972	$self->_drain_rbuf;
		973
		974	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		975	return $self->error;
184	}	976	}
185	});	977	});
		978	}
186	}	979	}
187		980
188	=item B<on_error ($callback)>	981	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) = @_;	982	my ($self) = @_;
240		983
241	$self->{read_cb} = $cb;	984	if (length $self->{_tls_wbuf}) {
242	my $old_blk_size = $self->{read_block_size};	985	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
243	$self->{read_block_size} = $len;	986	substr $self->{_tls_wbuf}, 0, $len, "";
244
245	$self->on_read (sub {
246	#d# warn "OFOFO $len || ".length($_[0]->{rbuf})."||\n";
247
248	if ($len == length $_[0]->{rbuf}) {
249	$_[0]->{read_block_size} = $old_blk_size;
250	$_[0]->on_read (undef);
251	$_[0]->{read_cb}->($_[0], (substr $self->{rbuf}, 0, $len, ''));
252	}	987	}
253	});	988	}
254	}
255		989
256	=item B<readlines ($callback)>	990	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
257		991	$self->{wbuf} .= $buf;
258	=item B<readlines ($sep, $callback)>	992	$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	}	993	}
281		994
282	my $sep_len = length $sep;	995	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
		996	$self->{rbuf} .= $buf;
		997	$self->_drain_rbuf;
		998	}
283		999
284	$self->{on_readline} = $cb;	1000	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
285		1001
286	$self->on_read (sub {	1002	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
287	my @lines;	1003	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
288	my $rb = \$_[0]->{rbuf};	1004	$self->error;
289	my $pos;	1005	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
290	while (($pos = index ($$rb, $sep)) >= 0) {	1006	$! = &Errno::EIO;
291	push @lines, substr $$rb, 0, $pos + $sep_len, '';	1007	$self->error;
292	}	1008	}
293	$self->{on_readline}->($_[0], @lines);	1009
		1010	# all others are fine for our purposes
		1011	}
		1012	}
		1013
		1014	=item $handle->starttls ($tls[, $tls_ctx])
		1015
		1016	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1017	object is created, you can also do that at a later time by calling
		1018	C<starttls>.
		1019
		1020	The first argument is the same as the C<tls> constructor argument (either
		1021	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1022
		1023	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1024	used when AnyEvent::Handle has to create its own TLS connection object.
		1025
		1026	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1027	call and can be used or changed to your liking. Note that the handshake
		1028	might have already started when this function returns.
		1029
		1030	=cut
		1031
		1032	# TODO: maybe document...
		1033	sub starttls {
		1034	my ($self, $ssl, $ctx) = @_;
		1035
		1036	$self->stoptls;
		1037
		1038	if ($ssl eq "accept") {
		1039	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1040	Net::SSLeay::set_accept_state ($ssl);
		1041	} elsif ($ssl eq "connect") {
		1042	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1043	Net::SSLeay::set_connect_state ($ssl);
		1044	}
		1045
		1046	$self->{tls} = $ssl;
		1047
		1048	# basically, this is deep magic (because SSL_read should have the same issues)
		1049	# but the openssl maintainers basically said: "trust us, it just works".
		1050	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1051	# and mismaintained ssleay-module doesn't even offer them).
		1052	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1053	Net::SSLeay::CTX_set_mode ($self->{tls},
		1054	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1055	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1056
		1057	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1058	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1059
		1060	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1061
		1062	$self->{filter_w} = sub {
		1063	$_[0]{_tls_wbuf} .= ${$_[1]};
		1064	&_dotls;
294	});	1065	};
		1066	$self->{filter_r} = sub {
		1067	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
		1068	&_dotls;
		1069	};
295	}	1070	}
296		1071
297	=item B<write ($data)>	1072	=item $handle->stoptls
298		1073
299	=item B<write ($callback)>	1074	Destroys the SSL connection, if any. Partial read or write data will be
		1075	lost.
300		1076
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	1077	=cut
308		1078
309	sub write {	1079	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) = @_;	1080	my ($self) = @_;
318		1081
319	if ($self->{write_w}) {	1082	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		1083
329	my $wba = shift @{$self->{write_bufs}}	1084	delete $self->{_rbio};
330	or return;	1085	delete $self->{_wbio};
331		1086	delete $self->{_tls_wbuf};
332	unless (defined $wba->[0]) {	1087	delete $self->{filter_r};
333	$wba->[1]->($self) if $wba->[1];
334	$self->_check_writer;
335	return;
336	}
337
338	$self->{wbuf} = $wba->[0];
339	$self->{write_cb} = $wba->[1];
340
341	$self->{write_w} =
342	AnyEvent->io (poll => 'w', fh => $self->{fh}, cb => sub {
343	my $l = syswrite $self->{fh}, $self->{wbuf}, length $self->{wbuf};
344
345	if (not defined $l) {
346	return if $! == EAGAIN || $! == EINTR;
347	delete $self->{write_w};	1088	delete $self->{filter_w};
348	$self->{on_error}->($self) if $self->{on_error};	1089	}
349		1090
350	} else {	1091	sub DESTROY {
351	substr $self->{wbuf}, 0, $l, '';	1092	my $self = shift;
352		1093
353	if (length ($self->{wbuf}) == 0) {	1094	$self->stoptls;
354	$self->{write_cb}->($self) if $self->{write_cb};	1095	}
355		1096
356	delete $self->{write_w};	1097	=item AnyEvent::Handle::TLS_CTX
357	delete $self->{wbuf};
358	delete $self->{write_cb};
359		1098
360	$self->_check_writer;	1099	This function creates and returns the Net::SSLeay::CTX object used by
361	}	1100	default for TLS mode.
362	}	1101
363	});	1102	The context is created like this:
		1103
		1104	Net::SSLeay::load_error_strings;
		1105	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1106	Net::SSLeay::randomize;
		1107
		1108	my $CTX = Net::SSLeay::CTX_new;
		1109
		1110	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1111
		1112	=cut
		1113
		1114	our $TLS_CTX;
		1115
		1116	sub TLS_CTX() {
		1117	$TLS_CTX || do {
		1118	require Net::SSLeay;
		1119
		1120	Net::SSLeay::load_error_strings ();
		1121	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1122	Net::SSLeay::randomize ();
		1123
		1124	$TLS_CTX = Net::SSLeay::CTX_new ();
		1125
		1126	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1127
		1128	$TLS_CTX
		1129	}
364	}	1130	}
365		1131
366	=back	1132	=back
367		1133
		1134	=head1 SUBCLASSING AnyEvent::Handle
		1135
		1136	In many cases, you might want to subclass AnyEvent::Handle.
		1137
		1138	To make this easier, a given version of AnyEvent::Handle uses these
		1139	conventions:
		1140
		1141	=over 4
		1142
		1143	=item * all constructor arguments become object members.
		1144
		1145	At least initially, when you pass a C<tls>-argument to the constructor it
		1146	will end up in C<< $handle->{tls} >>. Those members might be changes or
		1147	mutated later on (for example C<tls> will hold the TLS connection object).
		1148
		1149	=item * other object member names are prefixed with an C<_>.
		1150
		1151	All object members not explicitly documented (internal use) are prefixed
		1152	with an underscore character, so the remaining non-C<_>-namespace is free
		1153	for use for subclasses.
		1154
		1155	=item * all members not documented here and not prefixed with an underscore
		1156	are free to use in subclasses.
		1157
		1158	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1159	member variables, but thats just life, at least it is documented.
		1160
		1161	=back
		1162
368	=head1 AUTHOR	1163	=head1 AUTHOR
369		1164
370	Robin Redeker, C<< <elmex at ta-sa.org> >>	1165	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
371		1166
372	=cut	1167	=cut
373		1168
374	1; # End of AnyEvent::Handle	1169	1; # End of AnyEvent::Handle

Diff Legend

–	Removed lines
+	Added lines
<	Changed lines
>	Changed lines