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Revision 1.20 by elmex, Sat May 24 08:16:50 2008 UTC vs.
Revision 1.191 by root, Sun Jan 31 22:33:45 2010 UTC

1	package AnyEvent::Handle;
2
3	no warnings;
4	use strict;
5
6	use AnyEvent ();
7	use AnyEvent::Util ();
8	use Scalar::Util ();
9	use Carp ();
10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;
12
13	=head1 NAME	1	=head1 NAME
14		2
15	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	3	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16
17	This module is experimental.
18
19	=cut
20
21	our $VERSION = '0.04';
22		4
23	=head1 SYNOPSIS	5	=head1 SYNOPSIS
24		6
25	use AnyEvent;	7	use AnyEvent;
26	use AnyEvent::Handle;	8	use AnyEvent::Handle;
27		9
28	my $cv = AnyEvent->condvar;	10	my $cv = AnyEvent->condvar;
29		11
30	my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	12	my $hdl; $hdl = new AnyEvent::Handle
31
32	#TODO
33
34	# or use the constructor to pass the callback:
35
36	my $ae_fh2 =
37	AnyEvent::Handle->new (
38	fh => \*STDIN,	13	fh => \*STDIN,
39	on_eof => sub {	14	on_error => sub {
40	$cv->broadcast;	15	my ($hdl, $fatal, $msg) = @_;
41	},	16	warn "got error $msg\n";
42	#TODO	17	$hdl->destroy;
		18	$cv->send;
43	);	19	};
44		20
45	$cv->wait;	21	# send some request line
		22	$hdl->push_write ("getinfo\015\012");
		23
		24	# read the response line
		25	$hdl->push_read (line => sub {
		26	my ($hdl, $line) = @_;
		27	warn "got line <$line>\n";
		28	$cv->send;
		29	});
		30
		31	$cv->recv;
46		32
47	=head1 DESCRIPTION	33	=head1 DESCRIPTION
48		34
49	This module is a helper module to make it easier to do event-based I/O on	35	This module is a helper module to make it easier to do event-based I/O on
50	filehandles. For utility functions for doing non-blocking connects and accepts	36	filehandles.
51	on sockets see L<AnyEvent::Util>.	37
		38	The L<AnyEvent::Intro> tutorial contains some well-documented
		39	AnyEvent::Handle examples.
52		40
53	In the following, when the documentation refers to of "bytes" then this	41	In the following, when the documentation refers to of "bytes" then this
54	means characters. As sysread and syswrite are used for all I/O, their	42	means characters. As sysread and syswrite are used for all I/O, their
55	treatment of characters applies to this module as well.	43	treatment of characters applies to this module as well.
56		44
		45	At the very minimum, you should specify C<fh> or C<connect>, and the
		46	C<on_error> callback.
		47
57	All callbacks will be invoked with the handle object as their first	48	All callbacks will be invoked with the handle object as their first
58	argument.	49	argument.
59		50
		51	=cut
		52
		53	package AnyEvent::Handle;
		54
		55	use Scalar::Util ();
		56	use List::Util ();
		57	use Carp ();
		58	use Errno qw(EAGAIN EINTR);
		59
		60	use AnyEvent (); BEGIN { AnyEvent::common_sense }
		61	use AnyEvent::Util qw(WSAEWOULDBLOCK);
		62
		63	our $VERSION = $AnyEvent::VERSION;
		64
		65	sub _load_func($) {
		66	my $func = $_[0];
		67
		68	unless (defined &$func) {
		69	my $pkg = $func;
		70	do {
		71	$pkg =~ s/::[^:]+$//
		72	or return;
		73	eval "require $pkg";
		74	} until defined &$func;
		75	}
		76
		77	\&$func
		78	}
		79
60	=head1 METHODS	80	=head1 METHODS
61		81
62	=over 4	82	=over 4
63		83
64	=item B<new (%args)>	84	=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
65		85
66	The constructor supports these arguments (all as key => value pairs).	86	The constructor supports these arguments (all as C<< key => value >> pairs).
67		87
68	=over 4	88	=over 4
69		89
70	=item fh => $filehandle [MANDATORY]	90	=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
71		91
72	The filehandle this L<AnyEvent::Handle> object will operate on.	92	The filehandle this L<AnyEvent::Handle> object will operate on.
73
74	NOTE: The filehandle will be set to non-blocking (using	93	NOTE: The filehandle will be set to non-blocking mode (using
75	AnyEvent::Util::fh_nonblocking).	94	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		95	that mode.
76		96
77	=item on_eof => $cb->($self)	97	=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
78		98
79	Set the callback to be called on EOF.	99	Try to connect to the specified host and service (port), using
		100	C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
		101	default C<peername>.
80		102
81	While not mandatory, it is highly recommended to set an eof callback,	103	You have to specify either this parameter, or C<fh>, above.
82	otherwise you might end up with a closed socket while you are still
83	waiting for data.
84		104
		105	It is possible to push requests on the read and write queues, and modify
		106	properties of the stream, even while AnyEvent::Handle is connecting.
		107
		108	When this parameter is specified, then the C<on_prepare>,
		109	C<on_connect_error> and C<on_connect> callbacks will be called under the
		110	appropriate circumstances:
		111
		112	=over 4
		113
85	=item on_error => $cb->($self)	114	=item on_prepare => $cb->($handle)
86		115
		116	This (rarely used) callback is called before a new connection is
		117	attempted, but after the file handle has been created. It could be used to
		118	prepare the file handle with parameters required for the actual connect
		119	(as opposed to settings that can be changed when the connection is already
		120	established).
		121
		122	The return value of this callback should be the connect timeout value in
		123	seconds (or C<0>, or C<undef>, or the empty list, to indicate the default
		124	timeout is to be used).
		125
		126	=item on_connect => $cb->($handle, $host, $port, $retry->())
		127
		128	This callback is called when a connection has been successfully established.
		129
		130	The actual numeric host and port (the socket peername) are passed as
		131	parameters, together with a retry callback.
		132
		133	When, for some reason, the handle is not acceptable, then calling
		134	C<$retry> will continue with the next connection target (in case of
		135	multi-homed hosts or SRV records there can be multiple connection
		136	endpoints). At the time it is called the read and write queues, eof
		137	status, tls status and similar properties of the handle will have been
		138	reset.
		139
		140	In most cases, ignoring the C<$retry> parameter is the way to go.
		141
		142	=item on_connect_error => $cb->($handle, $message)
		143
		144	This callback is called when the connection could not be
		145	established. C<$!> will contain the relevant error code, and C<$message> a
		146	message describing it (usually the same as C<"$!">).
		147
		148	If this callback isn't specified, then C<on_error> will be called with a
		149	fatal error instead.
		150
		151	=back
		152
		153	=item on_error => $cb->($handle, $fatal, $message)
		154
87	This is the fatal error callback, that is called when, well, a fatal error	155	This is the error callback, which is called when, well, some error
88	occurs, such as not being able to resolve the hostname, failure to connect	156	occured, such as not being able to resolve the hostname, failure to
89	or a read error.	157	connect or a read error.
90		158
91	The object will not be in a usable state when this callback has been	159	Some errors are fatal (which is indicated by C<$fatal> being true). On
92	called.	160	fatal errors the handle object will be destroyed (by a call to C<< ->
		161	destroy >>) after invoking the error callback (which means you are free to
		162	examine the handle object). Examples of fatal errors are an EOF condition
		163	with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In
		164	cases where the other side can close the connection at their will it is
		165	often easiest to not report C<EPIPE> errors in this callback.
		166
		167	AnyEvent::Handle tries to find an appropriate error code for you to check
		168	against, but in some cases (TLS errors), this does not work well. It is
		169	recommended to always output the C<$message> argument in human-readable
		170	error messages (it's usually the same as C<"$!">).
		171
		172	Non-fatal errors can be retried by simply returning, but it is recommended
		173	to simply ignore this parameter and instead abondon the handle object
		174	when this callback is invoked. Examples of non-fatal errors are timeouts
		175	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
93		176
94	On callback entrance, the value of C<$!> contains the operating system	177	On callback entrance, the value of C<$!> contains the operating system
95	error (or C<ENOSPC> or C<EPIPE>).	178	error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
		179	C<EPROTO>).
96		180
97	While not mandatory, it is I<highly> recommended to set this callback, as	181	While not mandatory, it is I<highly> recommended to set this callback, as
98	you will not be notified of errors otherwise. The default simply calls	182	you will not be notified of errors otherwise. The default simply calls
99	die.	183	C<croak>.
100		184
101	=item on_read => $cb->($self)	185	=item on_read => $cb->($handle)
102		186
103	This sets the default read callback, which is called when data arrives	187	This sets the default read callback, which is called when data arrives
104	and no read request is in the queue.	188	and no read request is in the queue (unlike read queue callbacks, this
		189	callback will only be called when at least one octet of data is in the
		190	read buffer).
105		191
106	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	192	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
107	method or access the C<$self->{rbuf}> member directly.	193	method or access the C<< $handle->{rbuf} >> member directly. Note that you
		194	must not enlarge or modify the read buffer, you can only remove data at
		195	the beginning from it.
108		196
109	When an EOF condition is detected then AnyEvent::Handle will first try to	197	When an EOF condition is detected then AnyEvent::Handle will first try to
110	feed all the remaining data to the queued callbacks and C<on_read> before	198	feed all the remaining data to the queued callbacks and C<on_read> before
111	calling the C<on_eof> callback. If no progress can be made, then a fatal	199	calling the C<on_eof> callback. If no progress can be made, then a fatal
112	error will be raised (with C<$!> set to C<EPIPE>).	200	error will be raised (with C<$!> set to C<EPIPE>).
113		201
		202	Note that, unlike requests in the read queue, an C<on_read> callback
		203	doesn't mean you I<require> some data: if there is an EOF and there
		204	are outstanding read requests then an error will be flagged. With an
		205	C<on_read> callback, the C<on_eof> callback will be invoked.
		206
		207	=item on_eof => $cb->($handle)
		208
		209	Set the callback to be called when an end-of-file condition is detected,
		210	i.e. in the case of a socket, when the other side has closed the
		211	connection cleanly, and there are no outstanding read requests in the
		212	queue (if there are read requests, then an EOF counts as an unexpected
		213	connection close and will be flagged as an error).
		214
		215	For sockets, this just means that the other side has stopped sending data,
		216	you can still try to write data, and, in fact, one can return from the EOF
		217	callback and continue writing data, as only the read part has been shut
		218	down.
		219
		220	If an EOF condition has been detected but no C<on_eof> callback has been
		221	set, then a fatal error will be raised with C<$!> set to <0>.
		222
114	=item on_drain => $cb->()	223	=item on_drain => $cb->($handle)
115		224
116	This sets the callback that is called when the write buffer becomes empty	225	This sets the callback that is called when the write buffer becomes empty
117	(or when the callback is set and the buffer is empty already).	226	(or when the callback is set and the buffer is empty already).
118		227
119	To append to the write buffer, use the C<< ->push_write >> method.	228	To append to the write buffer, use the C<< ->push_write >> method.
120		229
		230	This callback is useful when you don't want to put all of your write data
		231	into the queue at once, for example, when you want to write the contents
		232	of some file to the socket you might not want to read the whole file into
		233	memory and push it into the queue, but instead only read more data from
		234	the file when the write queue becomes empty.
		235
		236	=item timeout => $fractional_seconds
		237
		238	=item rtimeout => $fractional_seconds
		239
		240	=item wtimeout => $fractional_seconds
		241
		242	If non-zero, then these enables an "inactivity" timeout: whenever this
		243	many seconds pass without a successful read or write on the underlying
		244	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
		245	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
		246	error will be raised).
		247
		248	There are three variants of the timeouts that work fully independent
		249	of each other, for both read and write, just read, and just write:
		250	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
		251	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
		252	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
		253
		254	Note that timeout processing is also active when you currently do not have
		255	any outstanding read or write requests: If you plan to keep the connection
		256	idle then you should disable the timout temporarily or ignore the timeout
		257	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		258	restart the timeout.
		259
		260	Zero (the default) disables this timeout.
		261
		262	=item on_timeout => $cb->($handle)
		263
		264	Called whenever the inactivity timeout passes. If you return from this
		265	callback, then the timeout will be reset as if some activity had happened,
		266	so this condition is not fatal in any way.
		267
121	=item rbuf_max => <bytes>	268	=item rbuf_max => <bytes>
122		269
123	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	270	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
124	when the read buffer ever (strictly) exceeds this size. This is useful to	271	when the read buffer ever (strictly) exceeds this size. This is useful to
125	avoid denial-of-service attacks.	272	avoid some forms of denial-of-service attacks.
126		273
127	For example, a server accepting connections from untrusted sources should	274	For example, a server accepting connections from untrusted sources should
128	be configured to accept only so-and-so much data that it cannot act on	275	be configured to accept only so-and-so much data that it cannot act on
129	(for example, when expecting a line, an attacker could send an unlimited	276	(for example, when expecting a line, an attacker could send an unlimited
130	amount of data without a callback ever being called as long as the line	277	amount of data without a callback ever being called as long as the line
131	isn't finished).	278	isn't finished).
132		279
		280	=item autocork => <boolean>
		281
		282	When disabled (the default), then C<push_write> will try to immediately
		283	write the data to the handle, if possible. This avoids having to register
		284	a write watcher and wait for the next event loop iteration, but can
		285	be inefficient if you write multiple small chunks (on the wire, this
		286	disadvantage is usually avoided by your kernel's nagle algorithm, see
		287	C<no_delay>, but this option can save costly syscalls).
		288
		289	When enabled, then writes will always be queued till the next event loop
		290	iteration. This is efficient when you do many small writes per iteration,
		291	but less efficient when you do a single write only per iteration (or when
		292	the write buffer often is full). It also increases write latency.
		293
		294	=item no_delay => <boolean>
		295
		296	When doing small writes on sockets, your operating system kernel might
		297	wait a bit for more data before actually sending it out. This is called
		298	the Nagle algorithm, and usually it is beneficial.
		299
		300	In some situations you want as low a delay as possible, which can be
		301	accomplishd by setting this option to a true value.
		302
		303	The default is your opertaing system's default behaviour (most likely
		304	enabled), this option explicitly enables or disables it, if possible.
		305
		306	=item keepalive => <boolean>
		307
		308	Enables (default disable) the SO_KEEPALIVE option on the stream socket:
		309	normally, TCP connections have no time-out once established, so TCP
		310	connections, once established, can stay alive forever even when the other
		311	side has long gone. TCP keepalives are a cheap way to take down long-lived
		312	TCP connections whent he other side becomes unreachable. While the default
		313	is OS-dependent, TCP keepalives usually kick in after around two hours,
		314	and, if the other side doesn't reply, take down the TCP connection some 10
		315	to 15 minutes later.
		316
		317	It is harmless to specify this option for file handles that do not support
		318	keepalives, and enabling it on connections that are potentially long-lived
		319	is usually a good idea.
		320
		321	=item oobinline => <boolean>
		322
		323	BSD majorly fucked up the implementation of TCP urgent data. The result
		324	is that almost no OS implements TCP according to the specs, and every OS
		325	implements it slightly differently.
		326
		327	If you want to handle TCP urgent data, then setting this flag (the default
		328	is enabled) gives you the most portable way of getting urgent data, by
		329	putting it into the stream.
		330
		331	Since BSD emulation of OOB data on top of TCP's urgent data can have
		332	security implications, AnyEvent::Handle sets this flag automatically
		333	unless explicitly specified. Note that setting this flag after
		334	establishing a connection I<may> be a bit too late (data loss could
		335	already have occured on BSD systems), but at least it will protect you
		336	from most attacks.
		337
133	=item read_size => <bytes>	338	=item read_size => <bytes>
134		339
135	The default read block size (the amount of bytes this module will try to read	340	The default read block size (the amount of bytes this module will
136	on each [loop iteration). Default: C<4096>.	341	try to read during each loop iteration, which affects memory
		342	requirements). Default: C<8192>.
137		343
138	=item low_water_mark => <bytes>	344	=item low_water_mark => <bytes>
139		345
140	Sets the amount of bytes (default: C<0>) that make up an "empty" write	346	Sets the amount of bytes (default: C<0>) that make up an "empty" write
141	buffer: If the write reaches this size or gets even samller it is	347	buffer: If the write reaches this size or gets even samller it is
142	considered empty.	348	considered empty.
143		349
		350	Sometimes it can be beneficial (for performance reasons) to add data to
		351	the write buffer before it is fully drained, but this is a rare case, as
		352	the operating system kernel usually buffers data as well, so the default
		353	is good in almost all cases.
		354
		355	=item linger => <seconds>
		356
		357	If non-zero (default: C<3600>), then the destructor of the
		358	AnyEvent::Handle object will check whether there is still outstanding
		359	write data and will install a watcher that will write this data to the
		360	socket. No errors will be reported (this mostly matches how the operating
		361	system treats outstanding data at socket close time).
		362
		363	This will not work for partial TLS data that could not be encoded
		364	yet. This data will be lost. Calling the C<stoptls> method in time might
		365	help.
		366
		367	=item peername => $string
		368
		369	A string used to identify the remote site - usually the DNS hostname
		370	(I<not> IDN!) used to create the connection, rarely the IP address.
		371
		372	Apart from being useful in error messages, this string is also used in TLS
		373	peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
		374	verification will be skipped when C<peername> is not specified or
		375	C<undef>.
		376
144	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	377	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
145		378
146	When this parameter is given, it enables TLS (SSL) mode, that means it	379	When this parameter is given, it enables TLS (SSL) mode, that means
147	will start making tls handshake and will transparently encrypt/decrypt	380	AnyEvent will start a TLS handshake as soon as the connection has been
148	data.	381	established and will transparently encrypt/decrypt data afterwards.
149		382
150	For the TLS server side, use C<accept>, and for the TLS client side of a	383	All TLS protocol errors will be signalled as C<EPROTO>, with an
151	connection, use C<connect> mode.	384	appropriate error message.
		385
		386	TLS mode requires Net::SSLeay to be installed (it will be loaded
		387	automatically when you try to create a TLS handle): this module doesn't
		388	have a dependency on that module, so if your module requires it, you have
		389	to add the dependency yourself.
		390
		391	Unlike TCP, TLS has a server and client side: for the TLS server side, use
		392	C<accept>, and for the TLS client side of a connection, use C<connect>
		393	mode.
152		394
153	You can also provide your own TLS connection object, but you have	395	You can also provide your own TLS connection object, but you have
154	to make sure that you call either C<Net::SSLeay::set_connect_state>	396	to make sure that you call either C<Net::SSLeay::set_connect_state>
155	or C<Net::SSLeay::set_accept_state> on it before you pass it to	397	or C<Net::SSLeay::set_accept_state> on it before you pass it to
156	AnyEvent::Handle.	398	AnyEvent::Handle. Also, this module will take ownership of this connection
		399	object.
157		400
158	=item tls_ctx => $ssl_ctx	401	At some future point, AnyEvent::Handle might switch to another TLS
		402	implementation, then the option to use your own session object will go
		403	away.
159		404
		405	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		406	passing in the wrong integer will lead to certain crash. This most often
		407	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		408	segmentation fault.
		409
		410	See the C<< ->starttls >> method for when need to start TLS negotiation later.
		411
		412	=item tls_ctx => $anyevent_tls
		413
160	Use the given Net::SSLeay::CTX object to create the new TLS connection	414	Use the given C<AnyEvent::TLS> object to create the new TLS connection
161	(unless a connection object was specified directly). If this parameter is	415	(unless a connection object was specified directly). If this parameter is
162	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	416	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
163		417
		418	Instead of an object, you can also specify a hash reference with C<< key
		419	=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
		420	new TLS context object.
		421
		422	=item on_starttls => $cb->($handle, $success[, $error_message])
		423
		424	This callback will be invoked when the TLS/SSL handshake has finished. If
		425	C<$success> is true, then the TLS handshake succeeded, otherwise it failed
		426	(C<on_stoptls> will not be called in this case).
		427
		428	The session in C<< $handle->{tls} >> can still be examined in this
		429	callback, even when the handshake was not successful.
		430
		431	TLS handshake failures will not cause C<on_error> to be invoked when this
		432	callback is in effect, instead, the error message will be passed to C<on_starttls>.
		433
		434	Without this callback, handshake failures lead to C<on_error> being
		435	called, as normal.
		436
		437	Note that you cannot call C<starttls> right again in this callback. If you
		438	need to do that, start an zero-second timer instead whose callback can
		439	then call C<< ->starttls >> again.
		440
		441	=item on_stoptls => $cb->($handle)
		442
		443	When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
		444	set, then it will be invoked after freeing the TLS session. If it is not,
		445	then a TLS shutdown condition will be treated like a normal EOF condition
		446	on the handle.
		447
		448	The session in C<< $handle->{tls} >> can still be examined in this
		449	callback.
		450
		451	This callback will only be called on TLS shutdowns, not when the
		452	underlying handle signals EOF.
		453
		454	=item json => JSON or JSON::XS object
		455
		456	This is the json coder object used by the C<json> read and write types.
		457
		458	If you don't supply it, then AnyEvent::Handle will create and use a
		459	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		460	texts.
		461
		462	Note that you are responsible to depend on the JSON module if you want to
		463	use this functionality, as AnyEvent does not have a dependency itself.
		464
164	=back	465	=back
165		466
166	=cut	467	=cut
167		468
168	sub new {	469	sub new {
169	my $class = shift;	470	my $class = shift;
170
171	my $self = bless { @_ }, $class;	471	my $self = bless { @_ }, $class;
172		472
173	$self->{fh} or Carp::croak "mandatory argument fh is missing";	473	if ($self->{fh}) {
		474	$self->_start;
		475	return unless $self->{fh}; # could be gone by now
		476
		477	} elsif ($self->{connect}) {
		478	require AnyEvent::Socket;
		479
		480	$self->{peername} = $self->{connect}[0]
		481	unless exists $self->{peername};
		482
		483	$self->{_skip_drain_rbuf} = 1;
		484
		485	{
		486	Scalar::Util::weaken (my $self = $self);
		487
		488	$self->{_connect} =
		489	AnyEvent::Socket::tcp_connect (
		490	$self->{connect}[0],
		491	$self->{connect}[1],
		492	sub {
		493	my ($fh, $host, $port, $retry) = @_;
		494
		495	if ($fh) {
		496	$self->{fh} = $fh;
		497
		498	delete $self->{_skip_drain_rbuf};
		499	$self->_start;
		500
		501	$self->{on_connect}
		502	and $self->{on_connect}($self, $host, $port, sub {
		503	delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
		504	$self->{_skip_drain_rbuf} = 1;
		505	&$retry;
		506	});
		507
		508	} else {
		509	if ($self->{on_connect_error}) {
		510	$self->{on_connect_error}($self, "$!");
		511	$self->destroy;
		512	} else {
		513	$self->_error ($!, 1);
		514	}
		515	}
		516	},
		517	sub {
		518	local $self->{fh} = $_[0];
		519
		520	$self->{on_prepare}
		521	? $self->{on_prepare}->($self)
		522	: ()
		523	}
		524	);
		525	}
		526
		527	} else {
		528	Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
		529	}
		530
		531	$self
		532	}
		533
		534	sub _start {
		535	my ($self) = @_;
174		536
175	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	537	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
176		538
177	if ($self->{tls}) {	539	$self->{_activity} =
178	require Net::SSLeay;	540	$self->{_ractivity} =
		541	$self->{_wactivity} = AE::now;
		542
		543	$self->timeout (delete $self->{timeout} ) if $self->{timeout};
		544	$self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
		545	$self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
		546
		547	$self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
		548	$self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
		549
		550	$self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
		551
179	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	552	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
180	}	553	if $self->{tls};
181		554
182	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
183	$self->on_error (delete $self->{on_error}) if $self->{on_error};
184	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	555	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
185	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
186		556
187	$self->start_read;	557	$self->start_read
		558	if $self->{on_read} || @{ $self->{_queue} };
188		559
189	$self	560	$self->_drain_wbuf;
190	}	561	}
191		562
192	sub _shutdown {
193	my ($self) = @_;
194
195	delete $self->{rw};
196	delete $self->{ww};
197	delete $self->{fh};
198	}
199
200	sub error {	563	sub _error {
201	my ($self) = @_;	564	my ($self, $errno, $fatal, $message) = @_;
202		565
203	{	566	$! = $errno;
204	local $!;	567	$message ||= "$!";
205	$self->_shutdown;
206	}
207		568
208	if ($self->{on_error}) {	569	if ($self->{on_error}) {
209	$self->{on_error}($self);	570	$self->{on_error}($self, $fatal, $message);
210	} else {	571	$self->destroy if $fatal;
		572	} elsif ($self->{fh} || $self->{connect}) {
		573	$self->destroy;
211	die "AnyEvent::Handle uncaught fatal error: $!";	574	Carp::croak "AnyEvent::Handle uncaught error: $message";
212	}	575	}
213	}	576	}
214		577
215	=item $fh = $handle->fh	578	=item $fh = $handle->fh
216		579
217	This method returns the filehandle of the L<AnyEvent::Handle> object.	580	This method returns the file handle used to create the L<AnyEvent::Handle> object.
218		581
219	=cut	582	=cut
220		583
221	sub fh { $_[0]->{fh} }	584	sub fh { $_[0]{fh} }
222		585
223	=item $handle->on_error ($cb)	586	=item $handle->on_error ($cb)
224		587
225	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	588	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
226		589
…		…
238		601
239	sub on_eof {	602	sub on_eof {
240	$_[0]{on_eof} = $_[1];	603	$_[0]{on_eof} = $_[1];
241	}	604	}
242		605
		606	=item $handle->on_timeout ($cb)
		607
		608	=item $handle->on_rtimeout ($cb)
		609
		610	=item $handle->on_wtimeout ($cb)
		611
		612	Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
		613	callback, or disables the callback (but not the timeout) if C<$cb> =
		614	C<undef>. See the C<timeout> constructor argument and method.
		615
		616	=cut
		617
		618	# see below
		619
		620	=item $handle->autocork ($boolean)
		621
		622	Enables or disables the current autocork behaviour (see C<autocork>
		623	constructor argument). Changes will only take effect on the next write.
		624
		625	=cut
		626
		627	sub autocork {
		628	$_[0]{autocork} = $_[1];
		629	}
		630
		631	=item $handle->no_delay ($boolean)
		632
		633	Enables or disables the C<no_delay> setting (see constructor argument of
		634	the same name for details).
		635
		636	=cut
		637
		638	sub no_delay {
		639	$_[0]{no_delay} = $_[1];
		640
		641	eval {
		642	local $SIG{__DIE__};
		643	setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
		644	if $_[0]{fh};
		645	};
		646	}
		647
		648	=item $handle->keepalive ($boolean)
		649
		650	Enables or disables the C<keepalive> setting (see constructor argument of
		651	the same name for details).
		652
		653	=cut
		654
		655	sub keepalive {
		656	$_[0]{keepalive} = $_[1];
		657
		658	eval {
		659	local $SIG{__DIE__};
		660	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		661	if $_[0]{fh};
		662	};
		663	}
		664
		665	=item $handle->oobinline ($boolean)
		666
		667	Enables or disables the C<oobinline> setting (see constructor argument of
		668	the same name for details).
		669
		670	=cut
		671
		672	sub oobinline {
		673	$_[0]{oobinline} = $_[1];
		674
		675	eval {
		676	local $SIG{__DIE__};
		677	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
		678	if $_[0]{fh};
		679	};
		680	}
		681
		682	=item $handle->keepalive ($boolean)
		683
		684	Enables or disables the C<keepalive> setting (see constructor argument of
		685	the same name for details).
		686
		687	=cut
		688
		689	sub keepalive {
		690	$_[0]{keepalive} = $_[1];
		691
		692	eval {
		693	local $SIG{__DIE__};
		694	setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
		695	if $_[0]{fh};
		696	};
		697	}
		698
		699	=item $handle->on_starttls ($cb)
		700
		701	Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
		702
		703	=cut
		704
		705	sub on_starttls {
		706	$_[0]{on_starttls} = $_[1];
		707	}
		708
		709	=item $handle->on_stoptls ($cb)
		710
		711	Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
		712
		713	=cut
		714
		715	sub on_stoptls {
		716	$_[0]{on_stoptls} = $_[1];
		717	}
		718
		719	=item $handle->rbuf_max ($max_octets)
		720
		721	Configures the C<rbuf_max> setting (C<undef> disables it).
		722
		723	=cut
		724
		725	sub rbuf_max {
		726	$_[0]{rbuf_max} = $_[1];
		727	}
		728
		729	#############################################################################
		730
		731	=item $handle->timeout ($seconds)
		732
		733	=item $handle->rtimeout ($seconds)
		734
		735	=item $handle->wtimeout ($seconds)
		736
		737	Configures (or disables) the inactivity timeout.
		738
		739	=item $handle->timeout_reset
		740
		741	=item $handle->rtimeout_reset
		742
		743	=item $handle->wtimeout_reset
		744
		745	Reset the activity timeout, as if data was received or sent.
		746
		747	These methods are cheap to call.
		748
		749	=cut
		750
		751	for my $dir ("", "r", "w") {
		752	my $timeout = "${dir}timeout";
		753	my $tw = "_${dir}tw";
		754	my $on_timeout = "on_${dir}timeout";
		755	my $activity = "_${dir}activity";
		756	my $cb;
		757
		758	*$on_timeout = sub {
		759	$_[0]{$on_timeout} = $_[1];
		760	};
		761
		762	*$timeout = sub {
		763	my ($self, $new_value) = @_;
		764
		765	$self->{$timeout} = $new_value;
		766	delete $self->{$tw}; &$cb;
		767	};
		768
		769	*{"${dir}timeout_reset"} = sub {
		770	$_[0]{$activity} = AE::now;
		771	};
		772
		773	# main workhorse:
		774	# reset the timeout watcher, as neccessary
		775	# also check for time-outs
		776	$cb = sub {
		777	my ($self) = @_;
		778
		779	if ($self->{$timeout} && $self->{fh}) {
		780	my $NOW = AE::now;
		781
		782	# when would the timeout trigger?
		783	my $after = $self->{$activity} + $self->{$timeout} - $NOW;
		784
		785	# now or in the past already?
		786	if ($after <= 0) {
		787	$self->{$activity} = $NOW;
		788
		789	if ($self->{$on_timeout}) {
		790	$self->{$on_timeout}($self);
		791	} else {
		792	$self->_error (Errno::ETIMEDOUT);
		793	}
		794
		795	# callback could have changed timeout value, optimise
		796	return unless $self->{$timeout};
		797
		798	# calculate new after
		799	$after = $self->{$timeout};
		800	}
		801
		802	Scalar::Util::weaken $self;
		803	return unless $self; # ->error could have destroyed $self
		804
		805	$self->{$tw} ||= AE::timer $after, 0, sub {
		806	delete $self->{$tw};
		807	$cb->($self);
		808	};
		809	} else {
		810	delete $self->{$tw};
		811	}
		812	}
		813	}
		814
243	#############################################################################	815	#############################################################################
244		816
245	=back	817	=back
246		818
247	=head2 WRITE QUEUE	819	=head2 WRITE QUEUE
…		…
268	my ($self, $cb) = @_;	840	my ($self, $cb) = @_;
269		841
270	$self->{on_drain} = $cb;	842	$self->{on_drain} = $cb;
271		843
272	$cb->($self)	844	$cb->($self)
273	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	845	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
274	}	846	}
275		847
276	=item $handle->push_write ($data)	848	=item $handle->push_write ($data)
277		849
278	Queues the given scalar to be written. You can push as much data as you	850	Queues the given scalar to be written. You can push as much data as you
…		…
282	=cut	854	=cut
283		855
284	sub _drain_wbuf {	856	sub _drain_wbuf {
285	my ($self) = @_;	857	my ($self) = @_;
286		858
287	unless ($self->{ww}) {	859	if (!$self->{_ww} && length $self->{wbuf}) {
		860
288	Scalar::Util::weaken $self;	861	Scalar::Util::weaken $self;
		862
289	my $cb = sub {	863	my $cb = sub {
290	my $len = syswrite $self->{fh}, $self->{wbuf};	864	my $len = syswrite $self->{fh}, $self->{wbuf};
291		865
292	if ($len > 0) {	866	if (defined $len) {
293	substr $self->{wbuf}, 0, $len, "";	867	substr $self->{wbuf}, 0, $len, "";
294		868
		869	$self->{_activity} = $self->{_wactivity} = AE::now;
		870
295	$self->{on_drain}($self)	871	$self->{on_drain}($self)
296	if $self->{low_water_mark} >= length $self->{wbuf}	872	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
297	&& $self->{on_drain};	873	&& $self->{on_drain};
298		874
299	delete $self->{ww} unless length $self->{wbuf};	875	delete $self->{_ww} unless length $self->{wbuf};
300	} elsif ($! != EAGAIN && $! != EINTR) {	876	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
301	$self->error;	877	$self->_error ($!, 1);
302	}	878	}
303	};	879	};
304		880
305	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	881	# try to write data immediately
		882	$cb->() unless $self->{autocork};
306		883
307	$cb->($self);	884	# if still data left in wbuf, we need to poll
		885	$self->{_ww} = AE::io $self->{fh}, 1, $cb
		886	if length $self->{wbuf};
308	};	887	};
		888	}
		889
		890	our %WH;
		891
		892	# deprecated
		893	sub register_write_type($$) {
		894	$WH{$_[0]} = $_[1];
309	}	895	}
310		896
311	sub push_write {	897	sub push_write {
312	my $self = shift;	898	my $self = shift;
313		899
		900	if (@_ > 1) {
		901	my $type = shift;
		902
		903	@_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
		904	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
		905	->($self, @_);
		906	}
		907
		908	# we downgrade here to avoid hard-to-track-down bugs,
		909	# and diagnose the problem earlier and better.
		910
314	if ($self->{filter_w}) {	911	if ($self->{tls}) {
315	$self->{filter_w}->($self, \$_[0]);	912	utf8::downgrade $self->{_tls_wbuf} .= $_[0];
		913	&_dotls ($self) if $self->{fh};
316	} else {	914	} else {
317	$self->{wbuf} .= $_[0];	915	utf8::downgrade $self->{wbuf} .= $_[0];
318	$self->_drain_wbuf;	916	$self->_drain_wbuf if $self->{fh};
319	}	917	}
320	}	918	}
		919
		920	=item $handle->push_write (type => @args)
		921
		922	Instead of formatting your data yourself, you can also let this module
		923	do the job by specifying a type and type-specific arguments. You
		924	can also specify the (fully qualified) name of a package, in which
		925	case AnyEvent tries to load the package and then expects to find the
		926	C<anyevent_read_type> function inside (see "custom write types", below).
		927
		928	Predefined types are (if you have ideas for additional types, feel free to
		929	drop by and tell us):
		930
		931	=over 4
		932
		933	=item netstring => $string
		934
		935	Formats the given value as netstring
		936	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		937
		938	=cut
		939
		940	register_write_type netstring => sub {
		941	my ($self, $string) = @_;
		942
		943	(length $string) . ":$string,"
		944	};
		945
		946	=item packstring => $format, $data
		947
		948	An octet string prefixed with an encoded length. The encoding C<$format>
		949	uses the same format as a Perl C<pack> format, but must specify a single
		950	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		951	optional C<!>, C<< < >> or C<< > >> modifier).
		952
		953	=cut
		954
		955	register_write_type packstring => sub {
		956	my ($self, $format, $string) = @_;
		957
		958	pack "$format/a*", $string
		959	};
		960
		961	=item json => $array_or_hashref
		962
		963	Encodes the given hash or array reference into a JSON object. Unless you
		964	provide your own JSON object, this means it will be encoded to JSON text
		965	in UTF-8.
		966
		967	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		968	one end of a handle and read them at the other end without using any
		969	additional framing.
		970
		971	The generated JSON text is guaranteed not to contain any newlines: While
		972	this module doesn't need delimiters after or between JSON texts to be
		973	able to read them, many other languages depend on that.
		974
		975	A simple RPC protocol that interoperates easily with others is to send
		976	JSON arrays (or objects, although arrays are usually the better choice as
		977	they mimic how function argument passing works) and a newline after each
		978	JSON text:
		979
		980	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		981	$handle->push_write ("\012");
		982
		983	An AnyEvent::Handle receiver would simply use the C<json> read type and
		984	rely on the fact that the newline will be skipped as leading whitespace:
		985
		986	$handle->push_read (json => sub { my $array = $_[1]; ... });
		987
		988	Other languages could read single lines terminated by a newline and pass
		989	this line into their JSON decoder of choice.
		990
		991	=cut
		992
		993	sub json_coder() {
		994	eval { require JSON::XS; JSON::XS->new->utf8 }
		995	|| do { require JSON; JSON->new->utf8 }
		996	}
		997
		998	register_write_type json => sub {
		999	my ($self, $ref) = @_;
		1000
		1001	my $json = $self->{json} ||= json_coder;
		1002
		1003	$json->encode ($ref)
		1004	};
		1005
		1006	=item storable => $reference
		1007
		1008	Freezes the given reference using L<Storable> and writes it to the
		1009	handle. Uses the C<nfreeze> format.
		1010
		1011	=cut
		1012
		1013	register_write_type storable => sub {
		1014	my ($self, $ref) = @_;
		1015
		1016	require Storable;
		1017
		1018	pack "w/a*", Storable::nfreeze ($ref)
		1019	};
		1020
		1021	=back
		1022
		1023	=item $handle->push_shutdown
		1024
		1025	Sometimes you know you want to close the socket after writing your data
		1026	before it was actually written. One way to do that is to replace your
		1027	C<on_drain> handler by a callback that shuts down the socket (and set
		1028	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
		1029	replaces the C<on_drain> callback with:
		1030
		1031	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
		1032
		1033	This simply shuts down the write side and signals an EOF condition to the
		1034	the peer.
		1035
		1036	You can rely on the normal read queue and C<on_eof> handling
		1037	afterwards. This is the cleanest way to close a connection.
		1038
		1039	=cut
		1040
		1041	sub push_shutdown {
		1042	my ($self) = @_;
		1043
		1044	delete $self->{low_water_mark};
		1045	$self->on_drain (sub { shutdown $_[0]{fh}, 1 });
		1046	}
		1047
		1048	=item custom write types - Package::anyevent_write_type $handle, @args
		1049
		1050	Instead of one of the predefined types, you can also specify the name of
		1051	a package. AnyEvent will try to load the package and then expects to find
		1052	a function named C<anyevent_write_type> inside. If it isn't found, it
		1053	progressively tries to load the parent package until it either finds the
		1054	function (good) or runs out of packages (bad).
		1055
		1056	Whenever the given C<type> is used, C<push_write> will the function with
		1057	the handle object and the remaining arguments.
		1058
		1059	The function is supposed to return a single octet string that will be
		1060	appended to the write buffer, so you cna mentally treat this function as a
		1061	"arguments to on-the-wire-format" converter.
		1062
		1063	Example: implement a custom write type C<join> that joins the remaining
		1064	arguments using the first one.
		1065
		1066	$handle->push_write (My::Type => " ", 1,2,3);
		1067
		1068	# uses the following package, which can be defined in the "My::Type" or in
		1069	# the "My" modules to be auto-loaded, or just about anywhere when the
		1070	# My::Type::anyevent_write_type is defined before invoking it.
		1071
		1072	package My::Type;
		1073
		1074	sub anyevent_write_type {
		1075	my ($handle, $delim, @args) = @_;
		1076
		1077	join $delim, @args
		1078	}
		1079
		1080	=cut
321		1081
322	#############################################################################	1082	#############################################################################
323		1083
324	=back	1084	=back
325		1085
…		…
332	ways, the "simple" way, using only C<on_read> and the "complex" way, using	1092	ways, the "simple" way, using only C<on_read> and the "complex" way, using
333	a queue.	1093	a queue.
334		1094
335	In the simple case, you just install an C<on_read> callback and whenever	1095	In the simple case, you just install an C<on_read> callback and whenever
336	new data arrives, it will be called. You can then remove some data (if	1096	new data arrives, it will be called. You can then remove some data (if
337	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	1097	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
338	or not.	1098	leave the data there if you want to accumulate more (e.g. when only a
		1099	partial message has been received so far).
339		1100
340	In the more complex case, you want to queue multiple callbacks. In this	1101	In the more complex case, you want to queue multiple callbacks. In this
341	case, AnyEvent::Handle will call the first queued callback each time new	1102	case, AnyEvent::Handle will call the first queued callback each time new
342	data arrives and removes it when it has done its job (see C<push_read>,	1103	data arrives (also the first time it is queued) and removes it when it has
343	below).	1104	done its job (see C<push_read>, below).
344		1105
345	This way you can, for example, push three line-reads, followed by reading	1106	This way you can, for example, push three line-reads, followed by reading
346	a chunk of data, and AnyEvent::Handle will execute them in order.	1107	a chunk of data, and AnyEvent::Handle will execute them in order.
347		1108
348	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	1109	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
349	the specified number of bytes which give an XML datagram.	1110	the specified number of bytes which give an XML datagram.
350		1111
351	# in the default state, expect some header bytes	1112	# in the default state, expect some header bytes
352	$handle->on_read (sub {	1113	$handle->on_read (sub {
353	# some data is here, now queue the length-header-read (4 octets)	1114	# some data is here, now queue the length-header-read (4 octets)
354	shift->unshift_read_chunk (4, sub {	1115	shift->unshift_read (chunk => 4, sub {
355	# header arrived, decode	1116	# header arrived, decode
356	my $len = unpack "N", $_[1];	1117	my $len = unpack "N", $_[1];
357		1118
358	# now read the payload	1119	# now read the payload
359	shift->unshift_read_chunk ($len, sub {	1120	shift->unshift_read (chunk => $len, sub {
360	my $xml = $_[1];	1121	my $xml = $_[1];
361	# handle xml	1122	# handle xml
362	});	1123	});
363	});	1124	});
364	});	1125	});
365		1126
366	Example 2: Implement a client for a protocol that replies either with	1127	Example 2: Implement a client for a protocol that replies either with "OK"
367	"OK" and another line or "ERROR" for one request, and 64 bytes for the	1128	and another line or "ERROR" for the first request that is sent, and 64
368	second request. Due tot he availability of a full queue, we can just	1129	bytes for the second request. Due to the availability of a queue, we can
369	pipeline sending both requests and manipulate the queue as necessary in	1130	just pipeline sending both requests and manipulate the queue as necessary
370	the callbacks:	1131	in the callbacks.
371		1132
372	# request one	1133	When the first callback is called and sees an "OK" response, it will
		1134	C<unshift> another line-read. This line-read will be queued I<before> the
		1135	64-byte chunk callback.
		1136
		1137	# request one, returns either "OK + extra line" or "ERROR"
373	$handle->push_write ("request 1\015\012");	1138	$handle->push_write ("request 1\015\012");
374		1139
375	# we expect "ERROR" or "OK" as response, so push a line read	1140	# we expect "ERROR" or "OK" as response, so push a line read
376	$handle->push_read_line (sub {	1141	$handle->push_read (line => sub {
377	# if we got an "OK", we have to _prepend_ another line,	1142	# if we got an "OK", we have to _prepend_ another line,
378	# so it will be read before the second request reads its 64 bytes	1143	# so it will be read before the second request reads its 64 bytes
379	# which are already in the queue when this callback is called	1144	# which are already in the queue when this callback is called
380	# we don't do this in case we got an error	1145	# we don't do this in case we got an error
381	if ($_[1] eq "OK") {	1146	if ($_[1] eq "OK") {
382	$_[0]->unshift_read_line (sub {	1147	$_[0]->unshift_read (line => sub {
383	my $response = $_[1];	1148	my $response = $_[1];
384	...	1149	...
385	});	1150	});
386	}	1151	}
387	});	1152	});
388		1153
389	# request two	1154	# request two, simply returns 64 octets
390	$handle->push_write ("request 2\015\012");	1155	$handle->push_write ("request 2\015\012");
391		1156
392	# simply read 64 bytes, always	1157	# simply read 64 bytes, always
393	$handle->push_read_chunk (64, sub {	1158	$handle->push_read (chunk => 64, sub {
394	my $response = $_[1];	1159	my $response = $_[1];
395	...	1160	...
396	});	1161	});
397		1162
398	=over 4	1163	=over 4
399		1164
400	=cut	1165	=cut
401		1166
402	sub _drain_rbuf {	1167	sub _drain_rbuf {
403	my ($self) = @_;	1168	my ($self) = @_;
		1169
		1170	# avoid recursion
		1171	return if $self->{_skip_drain_rbuf};
		1172	local $self->{_skip_drain_rbuf} = 1;
		1173
		1174	while () {
		1175	# we need to use a separate tls read buffer, as we must not receive data while
		1176	# we are draining the buffer, and this can only happen with TLS.
		1177	$self->{rbuf} .= delete $self->{_tls_rbuf}
		1178	if exists $self->{_tls_rbuf};
		1179
		1180	my $len = length $self->{rbuf};
		1181
		1182	if (my $cb = shift @{ $self->{_queue} }) {
		1183	unless ($cb->($self)) {
		1184	# no progress can be made
		1185	# (not enough data and no data forthcoming)
		1186	$self->_error (Errno::EPIPE, 1), return
		1187	if $self->{_eof};
		1188
		1189	unshift @{ $self->{_queue} }, $cb;
		1190	last;
		1191	}
		1192	} elsif ($self->{on_read}) {
		1193	last unless $len;
		1194
		1195	$self->{on_read}($self);
		1196
		1197	if (
		1198	$len == length $self->{rbuf} # if no data has been consumed
		1199	&& !@{ $self->{_queue} } # and the queue is still empty
		1200	&& $self->{on_read} # but we still have on_read
		1201	) {
		1202	# no further data will arrive
		1203	# so no progress can be made
		1204	$self->_error (Errno::EPIPE, 1), return
		1205	if $self->{_eof};
		1206
		1207	last; # more data might arrive
		1208	}
		1209	} else {
		1210	# read side becomes idle
		1211	delete $self->{_rw} unless $self->{tls};
		1212	last;
		1213	}
		1214	}
		1215
		1216	if ($self->{_eof}) {
		1217	$self->{on_eof}
		1218	? $self->{on_eof}($self)
		1219	: $self->_error (0, 1, "Unexpected end-of-file");
		1220
		1221	return;
		1222	}
404		1223
405	if (	1224	if (
406	defined $self->{rbuf_max}	1225	defined $self->{rbuf_max}
407	&& $self->{rbuf_max} < length $self->{rbuf}	1226	&& $self->{rbuf_max} < length $self->{rbuf}
408	) {	1227	) {
409	$! = &Errno::ENOSPC; return $self->error;	1228	$self->_error (Errno::ENOSPC, 1), return;
410	}	1229	}
411		1230
412	return if $self->{in_drain};	1231	# may need to restart read watcher
413	local $self->{in_drain} = 1;	1232	unless ($self->{_rw}) {
414		1233	$self->start_read
415	while (my $len = length $self->{rbuf}) {	1234	if $self->{on_read} || @{ $self->{_queue} };
416	no strict 'refs';
417	if (my $cb = shift @{ $self->{queue} }) {
418	if (!$cb->($self)) {
419	if ($self->{eof}) {
420	# no progress can be made (not enough data and no data forthcoming)
421	$! = &Errno::EPIPE; return $self->error;
422	}
423
424	unshift @{ $self->{queue} }, $cb;
425	return;
426	}
427	} elsif ($self->{on_read}) {
428	$self->{on_read}($self);
429
430	if (
431	$self->{eof} # if no further data will arrive
432	&& $len == length $self->{rbuf} # and no data has been consumed
433	&& !@{ $self->{queue} } # and the queue is still empty
434	&& $self->{on_read} # and we still want to read data
435	) {
436	# then no progress can be made
437	$! = &Errno::EPIPE; return $self->error;
438	}
439	} else {
440	# read side becomes idle
441	delete $self->{rw};
442	return;
443	}
444	}
445
446	if ($self->{eof}) {
447	$self->_shutdown;
448	$self->{on_eof}($self)
449	if $self->{on_eof};
450	}	1235	}
451	}	1236	}
452		1237
453	=item $handle->on_read ($cb)	1238	=item $handle->on_read ($cb)
454		1239
…		…
460		1245
461	sub on_read {	1246	sub on_read {
462	my ($self, $cb) = @_;	1247	my ($self, $cb) = @_;
463		1248
464	$self->{on_read} = $cb;	1249	$self->{on_read} = $cb;
		1250	$self->_drain_rbuf if $cb;
465	}	1251	}
466		1252
467	=item $handle->rbuf	1253	=item $handle->rbuf
468		1254
469	Returns the read buffer (as a modifiable lvalue).	1255	Returns the read buffer (as a modifiable lvalue).
470		1256
471	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	1257	You can access the read buffer directly as the C<< ->{rbuf} >>
472	you want.	1258	member, if you want. However, the only operation allowed on the
		1259	read buffer (apart from looking at it) is removing data from its
		1260	beginning. Otherwise modifying or appending to it is not allowed and will
		1261	lead to hard-to-track-down bugs.
473		1262
474	NOTE: The read buffer should only be used or modified if the C<on_read>,	1263	NOTE: The read buffer should only be used or modified if the C<on_read>,
475	C<push_read> or C<unshift_read> methods are used. The other read methods	1264	C<push_read> or C<unshift_read> methods are used. The other read methods
476	automatically manage the read buffer.	1265	automatically manage the read buffer.
477		1266
…		…
500	interested in (which can be none at all) and return a true value. After returning	1289	interested in (which can be none at all) and return a true value. After returning
501	true, it will be removed from the queue.	1290	true, it will be removed from the queue.
502		1291
503	=cut	1292	=cut
504		1293
		1294	our %RH;
		1295
		1296	sub register_read_type($$) {
		1297	$RH{$_[0]} = $_[1];
		1298	}
		1299
505	sub push_read {	1300	sub push_read {
506	my ($self, $cb) = @_;	1301	my $self = shift;
		1302	my $cb = pop;
507		1303
		1304	if (@_) {
		1305	my $type = shift;
		1306
		1307	$cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
		1308	or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
		1309	->($self, $cb, @_);
		1310	}
		1311
508	push @{ $self->{queue} }, $cb;	1312	push @{ $self->{_queue} }, $cb;
509	$self->_drain_rbuf;	1313	$self->_drain_rbuf;
510	}	1314	}
511		1315
512	sub unshift_read {	1316	sub unshift_read {
513	my ($self, $cb) = @_;	1317	my $self = shift;
		1318	my $cb = pop;
514		1319
		1320	if (@_) {
		1321	my $type = shift;
		1322
		1323	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		1324	->($self, $cb, @_);
		1325	}
		1326
515	push @{ $self->{queue} }, $cb;	1327	unshift @{ $self->{_queue} }, $cb;
516	$self->_drain_rbuf;	1328	$self->_drain_rbuf;
517	}	1329	}
518		1330
519	=item $handle->push_read_chunk ($len, $cb->($self, $data))	1331	=item $handle->push_read (type => @args, $cb)
520		1332
521	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	1333	=item $handle->unshift_read (type => @args, $cb)
522		1334
523	Append the given callback to the end of the queue (C<push_read_chunk>) or	1335	Instead of providing a callback that parses the data itself you can chose
524	prepend it (C<unshift_read_chunk>).	1336	between a number of predefined parsing formats, for chunks of data, lines
		1337	etc. You can also specify the (fully qualified) name of a package, in
		1338	which case AnyEvent tries to load the package and then expects to find the
		1339	C<anyevent_read_type> function inside (see "custom read types", below).
525		1340
526	The callback will be called only once C<$len> bytes have been read, and	1341	Predefined types are (if you have ideas for additional types, feel free to
527	these C<$len> bytes will be passed to the callback.	1342	drop by and tell us):
528		1343
529	=cut	1344	=over 4
530		1345
531	sub _read_chunk($$) {	1346	=item chunk => $octets, $cb->($handle, $data)
		1347
		1348	Invoke the callback only once C<$octets> bytes have been read. Pass the
		1349	data read to the callback. The callback will never be called with less
		1350	data.
		1351
		1352	Example: read 2 bytes.
		1353
		1354	$handle->push_read (chunk => 2, sub {
		1355	warn "yay ", unpack "H*", $_[1];
		1356	});
		1357
		1358	=cut
		1359
		1360	register_read_type chunk => sub {
532	my ($self, $len, $cb) = @_;	1361	my ($self, $cb, $len) = @_;
533		1362
534	sub {	1363	sub {
535	$len <= length $_[0]{rbuf} or return;	1364	$len <= length $_[0]{rbuf} or return;
536	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	1365	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
537	1	1366	1
538	}	1367	}
539	}	1368	};
540		1369
541	sub push_read_chunk {	1370	=item line => [$eol, ]$cb->($handle, $line, $eol)
542	$_[0]->push_read (&_read_chunk);
543	}
544
545
546	sub unshift_read_chunk {
547	$_[0]->unshift_read (&_read_chunk);
548	}
549
550	=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
551
552	=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
553
554	Append the given callback to the end of the queue (C<push_read_line>) or
555	prepend it (C<unshift_read_line>).
556		1371
557	The callback will be called only once a full line (including the end of	1372	The callback will be called only once a full line (including the end of
558	line marker, C<$eol>) has been read. This line (excluding the end of line	1373	line marker, C<$eol>) has been read. This line (excluding the end of line
559	marker) will be passed to the callback as second argument (C<$line>), and	1374	marker) will be passed to the callback as second argument (C<$line>), and
560	the end of line marker as the third argument (C<$eol>).	1375	the end of line marker as the third argument (C<$eol>).
…		…
571	Partial lines at the end of the stream will never be returned, as they are	1386	Partial lines at the end of the stream will never be returned, as they are
572	not marked by the end of line marker.	1387	not marked by the end of line marker.
573		1388
574	=cut	1389	=cut
575		1390
576	sub _read_line($$) {	1391	register_read_type line => sub {
577	my $self = shift;	1392	my ($self, $cb, $eol) = @_;
578	my $cb = pop;
579	my $eol = @_ ? shift : qr|(\015?\012)|;
580	my $pos;
581		1393
		1394	if (@_ < 3) {
		1395	# this is more than twice as fast as the generic code below
		1396	sub {
		1397	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		1398
		1399	$cb->($_[0], $1, $2);
		1400	1
		1401	}
		1402	} else {
582	$eol = quotemeta $eol unless ref $eol;	1403	$eol = quotemeta $eol unless ref $eol;
583	$eol = qr|^(.*?)($eol)|s;	1404	$eol = qr|^(.*?)($eol)|s;
		1405
		1406	sub {
		1407	$_[0]{rbuf} =~ s/$eol// or return;
		1408
		1409	$cb->($_[0], $1, $2);
		1410	1
		1411	}
		1412	}
		1413	};
		1414
		1415	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1416
		1417	Makes a regex match against the regex object C<$accept> and returns
		1418	everything up to and including the match.
		1419
		1420	Example: read a single line terminated by '\n'.
		1421
		1422	$handle->push_read (regex => qr<\n>, sub { ... });
		1423
		1424	If C<$reject> is given and not undef, then it determines when the data is
		1425	to be rejected: it is matched against the data when the C<$accept> regex
		1426	does not match and generates an C<EBADMSG> error when it matches. This is
		1427	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1428	receive buffer overflow).
		1429
		1430	Example: expect a single decimal number followed by whitespace, reject
		1431	anything else (not the use of an anchor).
		1432
		1433	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1434
		1435	If C<$skip> is given and not C<undef>, then it will be matched against
		1436	the receive buffer when neither C<$accept> nor C<$reject> match,
		1437	and everything preceding and including the match will be accepted
		1438	unconditionally. This is useful to skip large amounts of data that you
		1439	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1440	have to start matching from the beginning. This is purely an optimisation
		1441	and is usually worth only when you expect more than a few kilobytes.
		1442
		1443	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1444	expect the header to be very large (it isn't in practise, but...), we use
		1445	a skip regex to skip initial portions. The skip regex is tricky in that
		1446	it only accepts something not ending in either \015 or \012, as these are
		1447	required for the accept regex.
		1448
		1449	$handle->push_read (regex =>
		1450	qr<\015\012\015\012>,
		1451	undef, # no reject
		1452	qr<^.*[^\015\012]>,
		1453	sub { ... });
		1454
		1455	=cut
		1456
		1457	register_read_type regex => sub {
		1458	my ($self, $cb, $accept, $reject, $skip) = @_;
		1459
		1460	my $data;
		1461	my $rbuf = \$self->{rbuf};
584		1462
585	sub {	1463	sub {
586	$_[0]{rbuf} =~ s/$eol// or return;	1464	# accept
		1465	if ($$rbuf =~ $accept) {
		1466	$data .= substr $$rbuf, 0, $+[0], "";
		1467	$cb->($self, $data);
		1468	return 1;
		1469	}
		1470
		1471	# reject
		1472	if ($reject && $$rbuf =~ $reject) {
		1473	$self->_error (Errno::EBADMSG);
		1474	}
587		1475
588	$cb->($_[0], $1, $2);	1476	# skip
		1477	if ($skip && $$rbuf =~ $skip) {
		1478	$data .= substr $$rbuf, 0, $+[0], "";
		1479	}
		1480
		1481	()
		1482	}
		1483	};
		1484
		1485	=item netstring => $cb->($handle, $string)
		1486
		1487	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1488
		1489	Throws an error with C<$!> set to EBADMSG on format violations.
		1490
		1491	=cut
		1492
		1493	register_read_type netstring => sub {
		1494	my ($self, $cb) = @_;
		1495
		1496	sub {
		1497	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1498	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1499	$self->_error (Errno::EBADMSG);
		1500	}
		1501	return;
		1502	}
		1503
		1504	my $len = $1;
		1505
		1506	$self->unshift_read (chunk => $len, sub {
		1507	my $string = $_[1];
		1508	$_[0]->unshift_read (chunk => 1, sub {
		1509	if ($_[1] eq ",") {
		1510	$cb->($_[0], $string);
		1511	} else {
		1512	$self->_error (Errno::EBADMSG);
		1513	}
		1514	});
		1515	});
		1516
589	1	1517	1
590	}	1518	}
591	}	1519	};
592		1520
593	sub push_read_line {	1521	=item packstring => $format, $cb->($handle, $string)
594	$_[0]->push_read (&_read_line);
595	}
596		1522
597	sub unshift_read_line {	1523	An octet string prefixed with an encoded length. The encoding C<$format>
598	$_[0]->unshift_read (&_read_line);	1524	uses the same format as a Perl C<pack> format, but must specify a single
599	}	1525	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1526	optional C<!>, C<< < >> or C<< > >> modifier).
		1527
		1528	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1529	EPP uses a prefix of C<N> (4 octtes).
		1530
		1531	Example: read a block of data prefixed by its length in BER-encoded
		1532	format (very efficient).
		1533
		1534	$handle->push_read (packstring => "w", sub {
		1535	my ($handle, $data) = @_;
		1536	});
		1537
		1538	=cut
		1539
		1540	register_read_type packstring => sub {
		1541	my ($self, $cb, $format) = @_;
		1542
		1543	sub {
		1544	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1545	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1546	or return;
		1547
		1548	$format = length pack $format, $len;
		1549
		1550	# bypass unshift if we already have the remaining chunk
		1551	if ($format + $len <= length $_[0]{rbuf}) {
		1552	my $data = substr $_[0]{rbuf}, $format, $len;
		1553	substr $_[0]{rbuf}, 0, $format + $len, "";
		1554	$cb->($_[0], $data);
		1555	} else {
		1556	# remove prefix
		1557	substr $_[0]{rbuf}, 0, $format, "";
		1558
		1559	# read remaining chunk
		1560	$_[0]->unshift_read (chunk => $len, $cb);
		1561	}
		1562
		1563	1
		1564	}
		1565	};
		1566
		1567	=item json => $cb->($handle, $hash_or_arrayref)
		1568
		1569	Reads a JSON object or array, decodes it and passes it to the
		1570	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1571
		1572	If a C<json> object was passed to the constructor, then that will be used
		1573	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1574
		1575	This read type uses the incremental parser available with JSON version
		1576	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1577	dependency on your own: this module will load the JSON module, but
		1578	AnyEvent does not depend on it itself.
		1579
		1580	Since JSON texts are fully self-delimiting, the C<json> read and write
		1581	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1582	the C<json> write type description, above, for an actual example.
		1583
		1584	=cut
		1585
		1586	register_read_type json => sub {
		1587	my ($self, $cb) = @_;
		1588
		1589	my $json = $self->{json} ||= json_coder;
		1590
		1591	my $data;
		1592	my $rbuf = \$self->{rbuf};
		1593
		1594	sub {
		1595	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
		1596
		1597	if ($ref) {
		1598	$self->{rbuf} = $json->incr_text;
		1599	$json->incr_text = "";
		1600	$cb->($self, $ref);
		1601
		1602	1
		1603	} elsif ($@) {
		1604	# error case
		1605	$json->incr_skip;
		1606
		1607	$self->{rbuf} = $json->incr_text;
		1608	$json->incr_text = "";
		1609
		1610	$self->_error (Errno::EBADMSG);
		1611
		1612	()
		1613	} else {
		1614	$self->{rbuf} = "";
		1615
		1616	()
		1617	}
		1618	}
		1619	};
		1620
		1621	=item storable => $cb->($handle, $ref)
		1622
		1623	Deserialises a L<Storable> frozen representation as written by the
		1624	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1625	data).
		1626
		1627	Raises C<EBADMSG> error if the data could not be decoded.
		1628
		1629	=cut
		1630
		1631	register_read_type storable => sub {
		1632	my ($self, $cb) = @_;
		1633
		1634	require Storable;
		1635
		1636	sub {
		1637	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1638	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1639	or return;
		1640
		1641	my $format = length pack "w", $len;
		1642
		1643	# bypass unshift if we already have the remaining chunk
		1644	if ($format + $len <= length $_[0]{rbuf}) {
		1645	my $data = substr $_[0]{rbuf}, $format, $len;
		1646	substr $_[0]{rbuf}, 0, $format + $len, "";
		1647	$cb->($_[0], Storable::thaw ($data));
		1648	} else {
		1649	# remove prefix
		1650	substr $_[0]{rbuf}, 0, $format, "";
		1651
		1652	# read remaining chunk
		1653	$_[0]->unshift_read (chunk => $len, sub {
		1654	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1655	$cb->($_[0], $ref);
		1656	} else {
		1657	$self->_error (Errno::EBADMSG);
		1658	}
		1659	});
		1660	}
		1661
		1662	1
		1663	}
		1664	};
		1665
		1666	=back
		1667
		1668	=item custom read types - Package::anyevent_read_type $handle, $cb, @args
		1669
		1670	Instead of one of the predefined types, you can also specify the name
		1671	of a package. AnyEvent will try to load the package and then expects to
		1672	find a function named C<anyevent_read_type> inside. If it isn't found, it
		1673	progressively tries to load the parent package until it either finds the
		1674	function (good) or runs out of packages (bad).
		1675
		1676	Whenever this type is used, C<push_read> will invoke the function with the
		1677	handle object, the original callback and the remaining arguments.
		1678
		1679	The function is supposed to return a callback (usually a closure) that
		1680	works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
		1681	mentally treat the function as a "configurable read type to read callback"
		1682	converter.
		1683
		1684	It should invoke the original callback when it is done reading (remember
		1685	to pass C<$handle> as first argument as all other callbacks do that,
		1686	although there is no strict requirement on this).
		1687
		1688	For examples, see the source of this module (F<perldoc -m
		1689	AnyEvent::Handle>, search for C<register_read_type>)).
600		1690
601	=item $handle->stop_read	1691	=item $handle->stop_read
602		1692
603	=item $handle->start_read	1693	=item $handle->start_read
604		1694
605	In rare cases you actually do not want to read anything from the	1695	In rare cases you actually do not want to read anything from the
606	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1696	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
607	any queued callbacks will be executed then. To start readign again, call	1697	any queued callbacks will be executed then. To start reading again, call
608	C<start_read>.	1698	C<start_read>.
		1699
		1700	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1701	you change the C<on_read> callback or push/unshift a read callback, and it
		1702	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1703	there are any read requests in the queue.
		1704
		1705	These methods will have no effect when in TLS mode (as TLS doesn't support
		1706	half-duplex connections).
609		1707
610	=cut	1708	=cut
611		1709
612	sub stop_read {	1710	sub stop_read {
613	my ($self) = @_;	1711	my ($self) = @_;
614		1712
615	delete $self->{rw};	1713	delete $self->{_rw} unless $self->{tls};
616	}	1714	}
617		1715
618	sub start_read {	1716	sub start_read {
619	my ($self) = @_;	1717	my ($self) = @_;
620		1718
621	unless ($self->{rw} || $self->{eof}) {	1719	unless ($self->{_rw} || $self->{_eof}) {
622	Scalar::Util::weaken $self;	1720	Scalar::Util::weaken $self;
623		1721
624	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1722	$self->{_rw} = AE::io $self->{fh}, 0, sub {
625	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1723	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
626	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1724	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
627		1725
628	if ($len > 0) {	1726	if ($len > 0) {
629	$self->{filter_r}	1727	$self->{_activity} = $self->{_ractivity} = AE::now;
630	? $self->{filter_r}->($self, $rbuf)	1728
		1729	if ($self->{tls}) {
		1730	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1731
		1732	&_dotls ($self);
		1733	} else {
631	: $self->_drain_rbuf;	1734	$self->_drain_rbuf;
		1735	}
632		1736
633	} elsif (defined $len) {	1737	} elsif (defined $len) {
634	delete $self->{rw};	1738	delete $self->{_rw};
635	$self->{eof} = 1;	1739	$self->{_eof} = 1;
636	$self->_drain_rbuf;	1740	$self->_drain_rbuf;
637		1741
638	} elsif ($! != EAGAIN && $! != EINTR) {	1742	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
639	return $self->error;	1743	return $self->_error ($!, 1);
640	}	1744	}
641	});	1745	};
642	}	1746	}
643	}	1747	}
644		1748
		1749	our $ERROR_SYSCALL;
		1750	our $ERROR_WANT_READ;
		1751
		1752	sub _tls_error {
		1753	my ($self, $err) = @_;
		1754
		1755	return $self->_error ($!, 1)
		1756	if $err == Net::SSLeay::ERROR_SYSCALL ();
		1757
		1758	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
		1759
		1760	# reduce error string to look less scary
		1761	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
		1762
		1763	if ($self->{_on_starttls}) {
		1764	(delete $self->{_on_starttls})->($self, undef, $err);
		1765	&_freetls;
		1766	} else {
		1767	&_freetls;
		1768	$self->_error (Errno::EPROTO, 1, $err);
		1769	}
		1770	}
		1771
		1772	# poll the write BIO and send the data if applicable
		1773	# also decode read data if possible
		1774	# this is basiclaly our TLS state machine
		1775	# more efficient implementations are possible with openssl,
		1776	# but not with the buggy and incomplete Net::SSLeay.
645	sub _dotls {	1777	sub _dotls {
646	my ($self) = @_;	1778	my ($self) = @_;
647		1779
		1780	my $tmp;
		1781
648	if (length $self->{tls_wbuf}) {	1782	if (length $self->{_tls_wbuf}) {
649	my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf});	1783	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
650	substr $self->{tls_wbuf}, 0, $len, "" if $len > 0;	1784	substr $self->{_tls_wbuf}, 0, $tmp, "";
651	}	1785	}
652		1786
		1787	$tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
		1788	return $self->_tls_error ($tmp)
		1789	if $tmp != $ERROR_WANT_READ
		1790	&& ($tmp != $ERROR_SYSCALL || $!);
		1791	}
		1792
653	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) {	1793	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1794	unless (length $tmp) {
		1795	$self->{_on_starttls}
		1796	and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
		1797	&_freetls;
		1798
		1799	if ($self->{on_stoptls}) {
		1800	$self->{on_stoptls}($self);
		1801	return;
		1802	} else {
		1803	# let's treat SSL-eof as we treat normal EOF
		1804	delete $self->{_rw};
		1805	$self->{_eof} = 1;
		1806	}
		1807	}
		1808
		1809	$self->{_tls_rbuf} .= $tmp;
		1810	$self->_drain_rbuf;
		1811	$self->{tls} or return; # tls session might have gone away in callback
		1812	}
		1813
		1814	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1815	return $self->_tls_error ($tmp)
		1816	if $tmp != $ERROR_WANT_READ
		1817	&& ($tmp != $ERROR_SYSCALL || $!);
		1818
		1819	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
654	$self->{wbuf} .= $buf;	1820	$self->{wbuf} .= $tmp;
655	$self->_drain_wbuf;	1821	$self->_drain_wbuf;
656	}	1822	}
657		1823
658	if (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {	1824	$self->{_on_starttls}
659	$self->{rbuf} .= $buf;	1825	and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
660	$self->_drain_rbuf;	1826	and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
661	} elsif (	1827	}
662	(my $err = Net::SSLeay::get_error ($self->{tls}, -1))	1828
		1829	=item $handle->starttls ($tls[, $tls_ctx])
		1830
		1831	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1832	object is created, you can also do that at a later time by calling
		1833	C<starttls>.
		1834
		1835	Starting TLS is currently an asynchronous operation - when you push some
		1836	write data and then call C<< ->starttls >> then TLS negotiation will start
		1837	immediately, after which the queued write data is then sent.
		1838
		1839	The first argument is the same as the C<tls> constructor argument (either
		1840	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1841
		1842	The second argument is the optional C<AnyEvent::TLS> object that is used
		1843	when AnyEvent::Handle has to create its own TLS connection object, or
		1844	a hash reference with C<< key => value >> pairs that will be used to
		1845	construct a new context.
		1846
		1847	The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
		1848	context in C<< $handle->{tls_ctx} >> after this call and can be used or
		1849	changed to your liking. Note that the handshake might have already started
		1850	when this function returns.
		1851
		1852	Due to bugs in OpenSSL, it might or might not be possible to do multiple
		1853	handshakes on the same stream. Best do not attempt to use the stream after
		1854	stopping TLS.
		1855
		1856	=cut
		1857
		1858	our %TLS_CACHE; #TODO not yet documented, should we?
		1859
		1860	sub starttls {
		1861	my ($self, $tls, $ctx) = @_;
		1862
		1863	Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
		1864	if $self->{tls};
		1865
		1866	$self->{tls} = $tls;
		1867	$self->{tls_ctx} = $ctx if @_ > 2;
		1868
		1869	return unless $self->{fh};
		1870
		1871	require Net::SSLeay;
		1872
		1873	$ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
663	!= Net::SSLeay::ERROR_WANT_READ ()	1874	$ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
664	) {	1875
665	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {	1876	$tls = delete $self->{tls};
666	$self->error;	1877	$ctx = $self->{tls_ctx};
667	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1878
668	$! = &Errno::EIO;	1879	local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
669	$self->error;	1880
		1881	if ("HASH" eq ref $ctx) {
		1882	require AnyEvent::TLS;
		1883
		1884	if ($ctx->{cache}) {
		1885	my $key = $ctx+0;
		1886	$ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
		1887	} else {
		1888	$ctx = new AnyEvent::TLS %$ctx;
670	}	1889	}
671		1890	}
672	# all others are fine for our purposes
673	}	1891
674	}	1892	$self->{tls_ctx} = $ctx || TLS_CTX ();
		1893	$self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
675		1894
676	# TODO: maybe document...	1895	# basically, this is deep magic (because SSL_read should have the same issues)
677	sub starttls {	1896	# but the openssl maintainers basically said: "trust us, it just works".
678	my ($self, $ssl, $ctx) = @_;	1897	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
679		1898	# and mismaintained ssleay-module doesn't even offer them).
680	if ($ssl eq "accept") {	1899	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
681	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
682	Net::SSLeay::set_accept_state ($ssl);
683	} elsif ($ssl eq "connect") {
684	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
685	Net::SSLeay::set_connect_state ($ssl);
686	}	1900	#
		1901	# in short: this is a mess.
		1902	#
		1903	# note that we do not try to keep the length constant between writes as we are required to do.
		1904	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1905	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1906	# have identity issues in that area.
		1907	# Net::SSLeay::CTX_set_mode ($ssl,
		1908	# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1909	# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1910	Net::SSLeay::CTX_set_mode ($tls, 1|2);
687		1911
688	$self->{tls} = $ssl;
689
690	$self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1912	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
691	$self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1913	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
692		1914
		1915	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});
		1916
693	Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio});	1917	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
694		1918
695	$self->{filter_w} = sub {	1919	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
696	$_[0]{tls_wbuf} .= ${$_[1]};	1920	if $self->{on_starttls};
		1921
		1922	&_dotls; # need to trigger the initial handshake
		1923	$self->start_read; # make sure we actually do read
		1924	}
		1925
		1926	=item $handle->stoptls
		1927
		1928	Shuts down the SSL connection - this makes a proper EOF handshake by
		1929	sending a close notify to the other side, but since OpenSSL doesn't
		1930	support non-blocking shut downs, it is not guarenteed that you can re-use
		1931	the stream afterwards.
		1932
		1933	=cut
		1934
		1935	sub stoptls {
		1936	my ($self) = @_;
		1937
		1938	if ($self->{tls}) {
		1939	Net::SSLeay::shutdown ($self->{tls});
		1940
697	&_dotls;	1941	&_dotls;
		1942
		1943	# # we don't give a shit. no, we do, but we can't. no...#d#
		1944	# # we, we... have to use openssl :/#d#
		1945	# &_freetls;#d#
		1946	}
		1947	}
		1948
		1949	sub _freetls {
		1950	my ($self) = @_;
		1951
		1952	return unless $self->{tls};
		1953
		1954	$self->{tls_ctx}->_put_session (delete $self->{tls})
		1955	if $self->{tls} > 0;
		1956
		1957	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
		1958	}
		1959
		1960	sub DESTROY {
		1961	my ($self) = @_;
		1962
		1963	&_freetls;
		1964
		1965	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1966
		1967	if ($linger && length $self->{wbuf} && $self->{fh}) {
		1968	my $fh = delete $self->{fh};
		1969	my $wbuf = delete $self->{wbuf};
		1970
		1971	my @linger;
		1972
		1973	push @linger, AE::io $fh, 1, sub {
		1974	my $len = syswrite $fh, $wbuf, length $wbuf;
		1975
		1976	if ($len > 0) {
		1977	substr $wbuf, 0, $len, "";
		1978	} else {
		1979	@linger = (); # end
		1980	}
		1981	};
		1982	push @linger, AE::timer $linger, 0, sub {
		1983	@linger = ();
		1984	};
		1985	}
		1986	}
		1987
		1988	=item $handle->destroy
		1989
		1990	Shuts down the handle object as much as possible - this call ensures that
		1991	no further callbacks will be invoked and as many resources as possible
		1992	will be freed. Any method you will call on the handle object after
		1993	destroying it in this way will be silently ignored (and it will return the
		1994	empty list).
		1995
		1996	Normally, you can just "forget" any references to an AnyEvent::Handle
		1997	object and it will simply shut down. This works in fatal error and EOF
		1998	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1999	callback, so when you want to destroy the AnyEvent::Handle object from
		2000	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		2001	that case.
		2002
		2003	Destroying the handle object in this way has the advantage that callbacks
		2004	will be removed as well, so if those are the only reference holders (as
		2005	is common), then one doesn't need to do anything special to break any
		2006	reference cycles.
		2007
		2008	The handle might still linger in the background and write out remaining
		2009	data, as specified by the C<linger> option, however.
		2010
		2011	=cut
		2012
		2013	sub destroy {
		2014	my ($self) = @_;
		2015
		2016	$self->DESTROY;
		2017	%$self = ();
		2018	bless $self, "AnyEvent::Handle::destroyed";
		2019	}
		2020
		2021	sub AnyEvent::Handle::destroyed::AUTOLOAD {
		2022	#nop
		2023	}
		2024
		2025	=item AnyEvent::Handle::TLS_CTX
		2026
		2027	This function creates and returns the AnyEvent::TLS object used by default
		2028	for TLS mode.
		2029
		2030	The context is created by calling L<AnyEvent::TLS> without any arguments.
		2031
		2032	=cut
		2033
		2034	our $TLS_CTX;
		2035
		2036	sub TLS_CTX() {
		2037	$TLS_CTX ||= do {
		2038	require AnyEvent::TLS;
		2039
		2040	new AnyEvent::TLS
		2041	}
		2042	}
		2043
		2044	=back
		2045
		2046
		2047	=head1 NONFREQUENTLY ASKED QUESTIONS
		2048
		2049	=over 4
		2050
		2051	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		2052	still get further invocations!
		2053
		2054	That's because AnyEvent::Handle keeps a reference to itself when handling
		2055	read or write callbacks.
		2056
		2057	It is only safe to "forget" the reference inside EOF or error callbacks,
		2058	from within all other callbacks, you need to explicitly call the C<<
		2059	->destroy >> method.
		2060
		2061	=item I get different callback invocations in TLS mode/Why can't I pause
		2062	reading?
		2063
		2064	Unlike, say, TCP, TLS connections do not consist of two independent
		2065	communication channels, one for each direction. Or put differently. The
		2066	read and write directions are not independent of each other: you cannot
		2067	write data unless you are also prepared to read, and vice versa.
		2068
		2069	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		2070	callback invocations when you are not expecting any read data - the reason
		2071	is that AnyEvent::Handle always reads in TLS mode.
		2072
		2073	During the connection, you have to make sure that you always have a
		2074	non-empty read-queue, or an C<on_read> watcher. At the end of the
		2075	connection (or when you no longer want to use it) you can call the
		2076	C<destroy> method.
		2077
		2078	=item How do I read data until the other side closes the connection?
		2079
		2080	If you just want to read your data into a perl scalar, the easiest way
		2081	to achieve this is by setting an C<on_read> callback that does nothing,
		2082	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		2083	will be in C<$_[0]{rbuf}>:
		2084
		2085	$handle->on_read (sub { });
		2086	$handle->on_eof (undef);
		2087	$handle->on_error (sub {
		2088	my $data = delete $_[0]{rbuf};
		2089	});
		2090
		2091	The reason to use C<on_error> is that TCP connections, due to latencies
		2092	and packets loss, might get closed quite violently with an error, when in
		2093	fact, all data has been received.
		2094
		2095	It is usually better to use acknowledgements when transferring data,
		2096	to make sure the other side hasn't just died and you got the data
		2097	intact. This is also one reason why so many internet protocols have an
		2098	explicit QUIT command.
		2099
		2100	=item I don't want to destroy the handle too early - how do I wait until
		2101	all data has been written?
		2102
		2103	After writing your last bits of data, set the C<on_drain> callback
		2104	and destroy the handle in there - with the default setting of
		2105	C<low_water_mark> this will be called precisely when all data has been
		2106	written to the socket:
		2107
		2108	$handle->push_write (...);
		2109	$handle->on_drain (sub {
		2110	warn "all data submitted to the kernel\n";
		2111	undef $handle;
		2112	});
		2113
		2114	If you just want to queue some data and then signal EOF to the other side,
		2115	consider using C<< ->push_shutdown >> instead.
		2116
		2117	=item I want to contact a TLS/SSL server, I don't care about security.
		2118
		2119	If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
		2120	simply connect to it and then create the AnyEvent::Handle with the C<tls>
		2121	parameter:
		2122
		2123	tcp_connect $host, $port, sub {
		2124	my ($fh) = @_;
		2125
		2126	my $handle = new AnyEvent::Handle
		2127	fh => $fh,
		2128	tls => "connect",
		2129	on_error => sub { ... };
		2130
		2131	$handle->push_write (...);
698	};	2132	};
699	$self->{filter_r} = sub {
700	Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
701	&_dotls;
702	};
703	}
704		2133
705	sub DESTROY {	2134	=item I want to contact a TLS/SSL server, I do care about security.
706	my $self = shift;
707		2135
708	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	2136	Then you should additionally enable certificate verification, including
709	}	2137	peername verification, if the protocol you use supports it (see
		2138	L<AnyEvent::TLS>, C<verify_peername>).
710		2139
711	=item AnyEvent::Handle::TLS_CTX	2140	E.g. for HTTPS:
712		2141
713	This function creates and returns the Net::SSLeay::CTX object used by	2142	tcp_connect $host, $port, sub {
714	default for TLS mode.	2143	my ($fh) = @_;
715		2144
716	The context is created like this:	2145	my $handle = new AnyEvent::Handle
		2146	fh => $fh,
		2147	peername => $host,
		2148	tls => "connect",
		2149	tls_ctx => { verify => 1, verify_peername => "https" },
		2150	...
717		2151
718	Net::SSLeay::load_error_strings;	2152	Note that you must specify the hostname you connected to (or whatever
719	Net::SSLeay::SSLeay_add_ssl_algorithms;	2153	"peername" the protocol needs) as the C<peername> argument, otherwise no
720	Net::SSLeay::randomize;	2154	peername verification will be done.
721		2155
722	my $CTX = Net::SSLeay::CTX_new;	2156	The above will use the system-dependent default set of trusted CA
		2157	certificates. If you want to check against a specific CA, add the
		2158	C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
723		2159
724	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL	2160	tls_ctx => {
		2161	verify => 1,
		2162	verify_peername => "https",
		2163	ca_file => "my-ca-cert.pem",
		2164	},
725		2165
726	=cut	2166	=item I want to create a TLS/SSL server, how do I do that?
727		2167
728	our $TLS_CTX;	2168	Well, you first need to get a server certificate and key. You have
		2169	three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
		2170	self-signed certificate (cheap. check the search engine of your choice,
		2171	there are many tutorials on the net) or c) make your own CA (tinyca2 is a
		2172	nice program for that purpose).
729		2173
730	sub TLS_CTX() {	2174	Then create a file with your private key (in PEM format, see
731	$TLS_CTX || do {	2175	L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
732	require Net::SSLeay;	2176	file should then look like this:
733		2177
734	Net::SSLeay::load_error_strings ();	2178	-----BEGIN RSA PRIVATE KEY-----
735	Net::SSLeay::SSLeay_add_ssl_algorithms ();	2179	...header data
736	Net::SSLeay::randomize ();	2180	... lots of base64'y-stuff
		2181	-----END RSA PRIVATE KEY-----
737		2182
738	$TLS_CTX = Net::SSLeay::CTX_new ();	2183	-----BEGIN CERTIFICATE-----
		2184	... lots of base64'y-stuff
		2185	-----END CERTIFICATE-----
739		2186
740	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());	2187	The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
		2188	specify this file as C<cert_file>:
741		2189
742	$TLS_CTX	2190	tcp_server undef, $port, sub {
743	}	2191	my ($fh) = @_;
744	}	2192
		2193	my $handle = new AnyEvent::Handle
		2194	fh => $fh,
		2195	tls => "accept",
		2196	tls_ctx => { cert_file => "my-server-keycert.pem" },
		2197	...
		2198
		2199	When you have intermediate CA certificates that your clients might not
		2200	know about, just append them to the C<cert_file>.
745		2201
746	=back	2202	=back
747		2203
		2204
		2205	=head1 SUBCLASSING AnyEvent::Handle
		2206
		2207	In many cases, you might want to subclass AnyEvent::Handle.
		2208
		2209	To make this easier, a given version of AnyEvent::Handle uses these
		2210	conventions:
		2211
		2212	=over 4
		2213
		2214	=item * all constructor arguments become object members.
		2215
		2216	At least initially, when you pass a C<tls>-argument to the constructor it
		2217	will end up in C<< $handle->{tls} >>. Those members might be changed or
		2218	mutated later on (for example C<tls> will hold the TLS connection object).
		2219
		2220	=item * other object member names are prefixed with an C<_>.
		2221
		2222	All object members not explicitly documented (internal use) are prefixed
		2223	with an underscore character, so the remaining non-C<_>-namespace is free
		2224	for use for subclasses.
		2225
		2226	=item * all members not documented here and not prefixed with an underscore
		2227	are free to use in subclasses.
		2228
		2229	Of course, new versions of AnyEvent::Handle may introduce more "public"
		2230	member variables, but thats just life, at least it is documented.
		2231
		2232	=back
		2233
748	=head1 AUTHOR	2234	=head1 AUTHOR
749		2235
750	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	2236	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
751		2237
752	=cut	2238	=cut

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