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Revision 1.20 by elmex, Sat May 24 08:16:50 2008 UTC vs.
Revision 1.92 by root, Wed Oct 1 08:52:06 2008 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	no warnings;	3	no warnings;
4	use strict;	4	use strict qw(subs vars);
5		5
6	use AnyEvent ();	6	use AnyEvent ();
7	use AnyEvent::Util ();	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
10	use Fcntl ();	10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;	11	use Errno qw(EAGAIN EINTR);
12		12
13	=head1 NAME	13	=head1 NAME
14		14
15	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16		16
17	This module is experimental.
18
19	=cut	17	=cut
20		18
21	our $VERSION = '0.04';	19	our $VERSION = 4.3;
22		20
23	=head1 SYNOPSIS	21	=head1 SYNOPSIS
24		22
25	use AnyEvent;	23	use AnyEvent;
26	use AnyEvent::Handle;	24	use AnyEvent::Handle;
27		25
28	my $cv = AnyEvent->condvar;	26	my $cv = AnyEvent->condvar;
29		27
30	my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	28	my $handle =
31
32	#TODO
33
34	# or use the constructor to pass the callback:
35
36	my $ae_fh2 =
37	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
38	fh => \*STDIN,	30	fh => \*STDIN,
39	on_eof => sub {	31	on_eof => sub {
40	$cv->broadcast;	32	$cv->broadcast;
41	},	33	},
42	#TODO
43	);	34	);
44		35
45	$cv->wait;	36	# send some request line
		37	$handle->push_write ("getinfo\015\012");
		38
		39	# read the response line
		40	$handle->push_read (line => sub {
		41	my ($handle, $line) = @_;
		42	warn "read line <$line>\n";
		43	$cv->send;
		44	});
		45
		46	$cv->recv;
46		47
47	=head1 DESCRIPTION	48	=head1 DESCRIPTION
48		49
49	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
50	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
51	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
52		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
53	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
54	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
55	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
56		60
57	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
58	argument.	62	argument.
59		63
		64	=head2 SIGPIPE is not handled by this module
		65
		66	SIGPIPE is not handled by this module, so one of the practical
		67	requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} =
		68	'IGNORE'>). At least, this is highly recommend in a networked program: If
		69	you use AnyEvent::Handle in a filter program (like sort), exiting on
		70	SIGPIPE is probably the right thing to do.
		71
60	=head1 METHODS	72	=head1 METHODS
61		73
62	=over 4	74	=over 4
63		75
64	=item B<new (%args)>	76	=item B<new (%args)>
…		…
69		81
70	=item fh => $filehandle [MANDATORY]	82	=item fh => $filehandle [MANDATORY]
71		83
72	The filehandle this L<AnyEvent::Handle> object will operate on.	84	The filehandle this L<AnyEvent::Handle> object will operate on.
73		85
74	NOTE: The filehandle will be set to non-blocking (using	86	NOTE: The filehandle will be set to non-blocking mode (using
75	AnyEvent::Util::fh_nonblocking).	87	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		88	that mode.
76		89
77	=item on_eof => $cb->($self)	90	=item on_eof => $cb->($handle)
78		91
79	Set the callback to be called on EOF.	92	Set the callback to be called when an end-of-file condition is detected,
		93	i.e. in the case of a socket, when the other side has closed the
		94	connection cleanly.
80		95
		96	For sockets, this just means that the other side has stopped sending data,
		97	you can still try to write data, and, in fact, one can return from the eof
		98	callback and continue writing data, as only the read part has been shut
		99	down.
		100
81	While not mandatory, it is highly recommended to set an eof callback,	101	While not mandatory, it is I<highly> recommended to set an eof callback,
82	otherwise you might end up with a closed socket while you are still	102	otherwise you might end up with a closed socket while you are still
83	waiting for data.	103	waiting for data.
84		104
		105	If an EOF condition has been detected but no C<on_eof> callback has been
		106	set, then a fatal error will be raised with C<$!> set to <0>.
		107
85	=item on_error => $cb->($self)	108	=item on_error => $cb->($handle, $fatal)
86		109
87	This is the fatal error callback, that is called when, well, a fatal error	110	This is the error callback, which is called when, well, some error
88	occurs, such as not being able to resolve the hostname, failure to connect	111	occured, such as not being able to resolve the hostname, failure to
89	or a read error.	112	connect or a read error.
90		113
91	The object will not be in a usable state when this callback has been	114	Some errors are fatal (which is indicated by C<$fatal> being true). On
92	called.	115	fatal errors the handle object will be shut down and will not be usable
		116	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		117	errors are an EOF condition with active (but unsatisifable) read watchers
		118	(C<EPIPE>) or I/O errors.
		119
		120	Non-fatal errors can be retried by simply returning, but it is recommended
		121	to simply ignore this parameter and instead abondon the handle object
		122	when this callback is invoked. Examples of non-fatal errors are timeouts
		123	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
93		124
94	On callback entrance, the value of C<$!> contains the operating system	125	On callback entrance, the value of C<$!> contains the operating system
95	error (or C<ENOSPC> or C<EPIPE>).	126	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
96		127
97	While not mandatory, it is I<highly> recommended to set this callback, as	128	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	129	you will not be notified of errors otherwise. The default simply calls
99	die.	130	C<croak>.
100		131
101	=item on_read => $cb->($self)	132	=item on_read => $cb->($handle)
102		133
103	This sets the default read callback, which is called when data arrives	134	This sets the default read callback, which is called when data arrives
104	and no read request is in the queue.	135	and no read request is in the queue (unlike read queue callbacks, this
		136	callback will only be called when at least one octet of data is in the
		137	read buffer).
105		138
106	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	139	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
107	method or access the C<$self->{rbuf}> member directly.	140	method or access the C<$handle->{rbuf}> member directly.
108		141
109	When an EOF condition is detected then AnyEvent::Handle will first try to	142	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	143	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	144	calling the C<on_eof> callback. If no progress can be made, then a fatal
112	error will be raised (with C<$!> set to C<EPIPE>).	145	error will be raised (with C<$!> set to C<EPIPE>).
113		146
114	=item on_drain => $cb->()	147	=item on_drain => $cb->($handle)
115		148
116	This sets the callback that is called when the write buffer becomes empty	149	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).	150	(or when the callback is set and the buffer is empty already).
118		151
119	To append to the write buffer, use the C<< ->push_write >> method.	152	To append to the write buffer, use the C<< ->push_write >> method.
120		153
		154	This callback is useful when you don't want to put all of your write data
		155	into the queue at once, for example, when you want to write the contents
		156	of some file to the socket you might not want to read the whole file into
		157	memory and push it into the queue, but instead only read more data from
		158	the file when the write queue becomes empty.
		159
		160	=item timeout => $fractional_seconds
		161
		162	If non-zero, then this enables an "inactivity" timeout: whenever this many
		163	seconds pass without a successful read or write on the underlying file
		164	handle, the C<on_timeout> callback will be invoked (and if that one is
		165	missing, a non-fatal C<ETIMEDOUT> error will be raised).
		166
		167	Note that timeout processing is also active when you currently do not have
		168	any outstanding read or write requests: If you plan to keep the connection
		169	idle then you should disable the timout temporarily or ignore the timeout
		170	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		171	restart the timeout.
		172
		173	Zero (the default) disables this timeout.
		174
		175	=item on_timeout => $cb->($handle)
		176
		177	Called whenever the inactivity timeout passes. If you return from this
		178	callback, then the timeout will be reset as if some activity had happened,
		179	so this condition is not fatal in any way.
		180
121	=item rbuf_max => <bytes>	181	=item rbuf_max => <bytes>
122		182
123	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	183	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
124	when the read buffer ever (strictly) exceeds this size. This is useful to	184	when the read buffer ever (strictly) exceeds this size. This is useful to
125	avoid denial-of-service attacks.	185	avoid some forms of denial-of-service attacks.
126		186
127	For example, a server accepting connections from untrusted sources should	187	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	188	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	189	(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	190	amount of data without a callback ever being called as long as the line
131	isn't finished).	191	isn't finished).
132		192
		193	=item autocork => <boolean>
		194
		195	When disabled (the default), then C<push_write> will try to immediately
		196	write the data to the handle, if possible. This avoids having to register
		197	a write watcher and wait for the next event loop iteration, but can
		198	be inefficient if you write multiple small chunks (on the wire, this
		199	disadvantage is usually avoided by your kernel's nagle algorithm, see
		200	C<no_delay>, but this option can save costly syscalls).
		201
		202	When enabled, then writes will always be queued till the next event loop
		203	iteration. This is efficient when you do many small writes per iteration,
		204	but less efficient when you do a single write only per iteration (or when
		205	the write buffer often is full). It also increases write latency.
		206
		207	=item no_delay => <boolean>
		208
		209	When doing small writes on sockets, your operating system kernel might
		210	wait a bit for more data before actually sending it out. This is called
		211	the Nagle algorithm, and usually it is beneficial.
		212
		213	In some situations you want as low a delay as possible, which can be
		214	accomplishd by setting this option to a true value.
		215
		216	The default is your opertaing system's default behaviour (most likely
		217	enabled), this option explicitly enables or disables it, if possible.
		218
133	=item read_size => <bytes>	219	=item read_size => <bytes>
134		220
135	The default read block size (the amount of bytes this module will try to read	221	The default read block size (the amount of bytes this module will
136	on each [loop iteration). Default: C<4096>.	222	try to read during each loop iteration, which affects memory
		223	requirements). Default: C<8192>.
137		224
138	=item low_water_mark => <bytes>	225	=item low_water_mark => <bytes>
139		226
140	Sets the amount of bytes (default: C<0>) that make up an "empty" write	227	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	228	buffer: If the write reaches this size or gets even samller it is
142	considered empty.	229	considered empty.
143		230
		231	Sometimes it can be beneficial (for performance reasons) to add data to
		232	the write buffer before it is fully drained, but this is a rare case, as
		233	the operating system kernel usually buffers data as well, so the default
		234	is good in almost all cases.
		235
		236	=item linger => <seconds>
		237
		238	If non-zero (default: C<3600>), then the destructor of the
		239	AnyEvent::Handle object will check whether there is still outstanding
		240	write data and will install a watcher that will write this data to the
		241	socket. No errors will be reported (this mostly matches how the operating
		242	system treats outstanding data at socket close time).
		243
		244	This will not work for partial TLS data that could not be encoded
		245	yet. This data will be lost.
		246
144	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	247	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
145		248
146	When this parameter is given, it enables TLS (SSL) mode, that means it	249	When this parameter is given, it enables TLS (SSL) mode, that means
147	will start making tls handshake and will transparently encrypt/decrypt	250	AnyEvent will start a TLS handshake as soon as the conenction has been
148	data.	251	established and will transparently encrypt/decrypt data afterwards.
149		252
150	For the TLS server side, use C<accept>, and for the TLS client side of a	253	TLS mode requires Net::SSLeay to be installed (it will be loaded
151	connection, use C<connect> mode.	254	automatically when you try to create a TLS handle): this module doesn't
		255	have a dependency on that module, so if your module requires it, you have
		256	to add the dependency yourself.
		257
		258	Unlike TCP, TLS has a server and client side: for the TLS server side, use
		259	C<accept>, and for the TLS client side of a connection, use C<connect>
		260	mode.
152		261
153	You can also provide your own TLS connection object, but you have	262	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>	263	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	264	or C<Net::SSLeay::set_accept_state> on it before you pass it to
156	AnyEvent::Handle.	265	AnyEvent::Handle.
157		266
		267	See the C<< ->starttls >> method for when need to start TLS negotiation later.
		268
158	=item tls_ctx => $ssl_ctx	269	=item tls_ctx => $ssl_ctx
159		270
160	Use the given Net::SSLeay::CTX object to create the new TLS connection	271	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
161	(unless a connection object was specified directly). If this parameter is	272	(unless a connection object was specified directly). If this parameter is
162	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	273	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		274
		275	=item json => JSON or JSON::XS object
		276
		277	This is the json coder object used by the C<json> read and write types.
		278
		279	If you don't supply it, then AnyEvent::Handle will create and use a
		280	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		281	texts.
		282
		283	Note that you are responsible to depend on the JSON module if you want to
		284	use this functionality, as AnyEvent does not have a dependency itself.
		285
		286	=item filter_r => $cb
		287
		288	=item filter_w => $cb
		289
		290	These exist, but are undocumented at this time. (They are used internally
		291	by the TLS code).
163		292
164	=back	293	=back
165		294
166	=cut	295	=cut
167		296
…		…
177	if ($self->{tls}) {	306	if ($self->{tls}) {
178	require Net::SSLeay;	307	require Net::SSLeay;
179	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	308	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
180	}	309	}
181		310
182	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};	311	$self->{_activity} = AnyEvent->now;
183	$self->on_error (delete $self->{on_error}) if $self->{on_error};	312	$self->_timeout;
		313
184	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	314	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
185	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	315	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
186		316
187	$self->start_read;	317	$self->start_read
		318	if $self->{on_read};
188		319
189	$self	320	$self
190	}	321	}
191		322
192	sub _shutdown {	323	sub _shutdown {
193	my ($self) = @_;	324	my ($self) = @_;
194		325
		326	delete $self->{_tw};
195	delete $self->{rw};	327	delete $self->{_rw};
196	delete $self->{ww};	328	delete $self->{_ww};
197	delete $self->{fh};	329	delete $self->{fh};
198	}
199		330
		331	&_freetls;
		332
		333	delete $self->{on_read};
		334	delete $self->{_queue};
		335	}
		336
200	sub error {	337	sub _error {
201	my ($self) = @_;	338	my ($self, $errno, $fatal) = @_;
202		339
203	{
204	local $!;
205	$self->_shutdown;	340	$self->_shutdown
206	}	341	if $fatal;
		342
		343	$! = $errno;
207		344
208	if ($self->{on_error}) {	345	if ($self->{on_error}) {
209	$self->{on_error}($self);	346	$self->{on_error}($self, $fatal);
210	} else {	347	} else {
211	die "AnyEvent::Handle uncaught fatal error: $!";	348	Carp::croak "AnyEvent::Handle uncaught error: $!";
212	}	349	}
213	}	350	}
214		351
215	=item $fh = $handle->fh	352	=item $fh = $handle->fh
216		353
217	This method returns the filehandle of the L<AnyEvent::Handle> object.	354	This method returns the file handle used to create the L<AnyEvent::Handle> object.
218		355
219	=cut	356	=cut
220		357
221	sub fh { $_[0]->{fh} }	358	sub fh { $_[0]{fh} }
222		359
223	=item $handle->on_error ($cb)	360	=item $handle->on_error ($cb)
224		361
225	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	362	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
226		363
…		…
236		373
237	=cut	374	=cut
238		375
239	sub on_eof {	376	sub on_eof {
240	$_[0]{on_eof} = $_[1];	377	$_[0]{on_eof} = $_[1];
		378	}
		379
		380	=item $handle->on_timeout ($cb)
		381
		382	Replace the current C<on_timeout> callback, or disables the callback (but
		383	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
		384	argument and method.
		385
		386	=cut
		387
		388	sub on_timeout {
		389	$_[0]{on_timeout} = $_[1];
		390	}
		391
		392	=item $handle->autocork ($boolean)
		393
		394	Enables or disables the current autocork behaviour (see C<autocork>
		395	constructor argument).
		396
		397	=cut
		398
		399	=item $handle->no_delay ($boolean)
		400
		401	Enables or disables the C<no_delay> setting (see constructor argument of
		402	the same name for details).
		403
		404	=cut
		405
		406	sub no_delay {
		407	$_[0]{no_delay} = $_[1];
		408
		409	eval {
		410	local $SIG{__DIE__};
		411	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		412	};
		413	}
		414
		415	#############################################################################
		416
		417	=item $handle->timeout ($seconds)
		418
		419	Configures (or disables) the inactivity timeout.
		420
		421	=cut
		422
		423	sub timeout {
		424	my ($self, $timeout) = @_;
		425
		426	$self->{timeout} = $timeout;
		427	$self->_timeout;
		428	}
		429
		430	# reset the timeout watcher, as neccessary
		431	# also check for time-outs
		432	sub _timeout {
		433	my ($self) = @_;
		434
		435	if ($self->{timeout}) {
		436	my $NOW = AnyEvent->now;
		437
		438	# when would the timeout trigger?
		439	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		440
		441	# now or in the past already?
		442	if ($after <= 0) {
		443	$self->{_activity} = $NOW;
		444
		445	if ($self->{on_timeout}) {
		446	$self->{on_timeout}($self);
		447	} else {
		448	$self->_error (&Errno::ETIMEDOUT);
		449	}
		450
		451	# callback could have changed timeout value, optimise
		452	return unless $self->{timeout};
		453
		454	# calculate new after
		455	$after = $self->{timeout};
		456	}
		457
		458	Scalar::Util::weaken $self;
		459	return unless $self; # ->error could have destroyed $self
		460
		461	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		462	delete $self->{_tw};
		463	$self->_timeout;
		464	});
		465	} else {
		466	delete $self->{_tw};
		467	}
241	}	468	}
242		469
243	#############################################################################	470	#############################################################################
244		471
245	=back	472	=back
…		…
282	=cut	509	=cut
283		510
284	sub _drain_wbuf {	511	sub _drain_wbuf {
285	my ($self) = @_;	512	my ($self) = @_;
286		513
287	unless ($self->{ww}) {	514	if (!$self->{_ww} && length $self->{wbuf}) {
		515
288	Scalar::Util::weaken $self;	516	Scalar::Util::weaken $self;
		517
289	my $cb = sub {	518	my $cb = sub {
290	my $len = syswrite $self->{fh}, $self->{wbuf};	519	my $len = syswrite $self->{fh}, $self->{wbuf};
291		520
292	if ($len > 0) {	521	if ($len >= 0) {
293	substr $self->{wbuf}, 0, $len, "";	522	substr $self->{wbuf}, 0, $len, "";
		523
		524	$self->{_activity} = AnyEvent->now;
294		525
295	$self->{on_drain}($self)	526	$self->{on_drain}($self)
296	if $self->{low_water_mark} >= length $self->{wbuf}	527	if $self->{low_water_mark} >= length $self->{wbuf}
297	&& $self->{on_drain};	528	&& $self->{on_drain};
298		529
299	delete $self->{ww} unless length $self->{wbuf};	530	delete $self->{_ww} unless length $self->{wbuf};
300	} elsif ($! != EAGAIN && $! != EINTR) {	531	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
301	$self->error;	532	$self->_error ($!, 1);
302	}	533	}
303	};	534	};
304		535
		536	# try to write data immediately
		537	$cb->() unless $self->{autocork};
		538
		539	# if still data left in wbuf, we need to poll
305	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	540	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
306		541	if length $self->{wbuf};
307	$cb->($self);
308	};	542	};
		543	}
		544
		545	our %WH;
		546
		547	sub register_write_type($$) {
		548	$WH{$_[0]} = $_[1];
309	}	549	}
310		550
311	sub push_write {	551	sub push_write {
312	my $self = shift;	552	my $self = shift;
313		553
		554	if (@_ > 1) {
		555	my $type = shift;
		556
		557	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		558	->($self, @_);
		559	}
		560
314	if ($self->{filter_w}) {	561	if ($self->{filter_w}) {
315	$self->{filter_w}->($self, \$_[0]);	562	$self->{filter_w}($self, \$_[0]);
316	} else {	563	} else {
317	$self->{wbuf} .= $_[0];	564	$self->{wbuf} .= $_[0];
318	$self->_drain_wbuf;	565	$self->_drain_wbuf;
319	}	566	}
320	}	567	}
321		568
		569	=item $handle->push_write (type => @args)
		570
		571	Instead of formatting your data yourself, you can also let this module do
		572	the job by specifying a type and type-specific arguments.
		573
		574	Predefined types are (if you have ideas for additional types, feel free to
		575	drop by and tell us):
		576
		577	=over 4
		578
		579	=item netstring => $string
		580
		581	Formats the given value as netstring
		582	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		583
		584	=cut
		585
		586	register_write_type netstring => sub {
		587	my ($self, $string) = @_;
		588
		589	sprintf "%d:%s,", (length $string), $string
		590	};
		591
		592	=item packstring => $format, $data
		593
		594	An octet string prefixed with an encoded length. The encoding C<$format>
		595	uses the same format as a Perl C<pack> format, but must specify a single
		596	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		597	optional C<!>, C<< < >> or C<< > >> modifier).
		598
		599	=cut
		600
		601	register_write_type packstring => sub {
		602	my ($self, $format, $string) = @_;
		603
		604	pack "$format/a*", $string
		605	};
		606
		607	=item json => $array_or_hashref
		608
		609	Encodes the given hash or array reference into a JSON object. Unless you
		610	provide your own JSON object, this means it will be encoded to JSON text
		611	in UTF-8.
		612
		613	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		614	one end of a handle and read them at the other end without using any
		615	additional framing.
		616
		617	The generated JSON text is guaranteed not to contain any newlines: While
		618	this module doesn't need delimiters after or between JSON texts to be
		619	able to read them, many other languages depend on that.
		620
		621	A simple RPC protocol that interoperates easily with others is to send
		622	JSON arrays (or objects, although arrays are usually the better choice as
		623	they mimic how function argument passing works) and a newline after each
		624	JSON text:
		625
		626	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		627	$handle->push_write ("\012");
		628
		629	An AnyEvent::Handle receiver would simply use the C<json> read type and
		630	rely on the fact that the newline will be skipped as leading whitespace:
		631
		632	$handle->push_read (json => sub { my $array = $_[1]; ... });
		633
		634	Other languages could read single lines terminated by a newline and pass
		635	this line into their JSON decoder of choice.
		636
		637	=cut
		638
		639	register_write_type json => sub {
		640	my ($self, $ref) = @_;
		641
		642	require JSON;
		643
		644	$self->{json} ? $self->{json}->encode ($ref)
		645	: JSON::encode_json ($ref)
		646	};
		647
		648	=item storable => $reference
		649
		650	Freezes the given reference using L<Storable> and writes it to the
		651	handle. Uses the C<nfreeze> format.
		652
		653	=cut
		654
		655	register_write_type storable => sub {
		656	my ($self, $ref) = @_;
		657
		658	require Storable;
		659
		660	pack "w/a*", Storable::nfreeze ($ref)
		661	};
		662
		663	=back
		664
		665	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		666
		667	This function (not method) lets you add your own types to C<push_write>.
		668	Whenever the given C<type> is used, C<push_write> will invoke the code
		669	reference with the handle object and the remaining arguments.
		670
		671	The code reference is supposed to return a single octet string that will
		672	be appended to the write buffer.
		673
		674	Note that this is a function, and all types registered this way will be
		675	global, so try to use unique names.
		676
		677	=cut
		678
322	#############################################################################	679	#############################################################################
323		680
324	=back	681	=back
325		682
326	=head2 READ QUEUE	683	=head2 READ QUEUE
…		…
332	ways, the "simple" way, using only C<on_read> and the "complex" way, using	689	ways, the "simple" way, using only C<on_read> and the "complex" way, using
333	a queue.	690	a queue.
334		691
335	In the simple case, you just install an C<on_read> callback and whenever	692	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	693	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	694	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
338	or not.	695	leave the data there if you want to accumulate more (e.g. when only a
		696	partial message has been received so far).
339		697
340	In the more complex case, you want to queue multiple callbacks. In this	698	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	699	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>,	700	data arrives (also the first time it is queued) and removes it when it has
343	below).	701	done its job (see C<push_read>, below).
344		702
345	This way you can, for example, push three line-reads, followed by reading	703	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.	704	a chunk of data, and AnyEvent::Handle will execute them in order.
347		705
348	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	706	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
349	the specified number of bytes which give an XML datagram.	707	the specified number of bytes which give an XML datagram.
350		708
351	# in the default state, expect some header bytes	709	# in the default state, expect some header bytes
352	$handle->on_read (sub {	710	$handle->on_read (sub {
353	# some data is here, now queue the length-header-read (4 octets)	711	# some data is here, now queue the length-header-read (4 octets)
354	shift->unshift_read_chunk (4, sub {	712	shift->unshift_read (chunk => 4, sub {
355	# header arrived, decode	713	# header arrived, decode
356	my $len = unpack "N", $_[1];	714	my $len = unpack "N", $_[1];
357		715
358	# now read the payload	716	# now read the payload
359	shift->unshift_read_chunk ($len, sub {	717	shift->unshift_read (chunk => $len, sub {
360	my $xml = $_[1];	718	my $xml = $_[1];
361	# handle xml	719	# handle xml
362	});	720	});
363	});	721	});
364	});	722	});
365		723
366	Example 2: Implement a client for a protocol that replies either with	724	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	725	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	726	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	727	just pipeline sending both requests and manipulate the queue as necessary
370	the callbacks:	728	in the callbacks.
371		729
372	# request one	730	When the first callback is called and sees an "OK" response, it will
		731	C<unshift> another line-read. This line-read will be queued I<before> the
		732	64-byte chunk callback.
		733
		734	# request one, returns either "OK + extra line" or "ERROR"
373	$handle->push_write ("request 1\015\012");	735	$handle->push_write ("request 1\015\012");
374		736
375	# we expect "ERROR" or "OK" as response, so push a line read	737	# we expect "ERROR" or "OK" as response, so push a line read
376	$handle->push_read_line (sub {	738	$handle->push_read (line => sub {
377	# if we got an "OK", we have to _prepend_ another line,	739	# 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	740	# 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	741	# which are already in the queue when this callback is called
380	# we don't do this in case we got an error	742	# we don't do this in case we got an error
381	if ($_[1] eq "OK") {	743	if ($_[1] eq "OK") {
382	$_[0]->unshift_read_line (sub {	744	$_[0]->unshift_read (line => sub {
383	my $response = $_[1];	745	my $response = $_[1];
384	...	746	...
385	});	747	});
386	}	748	}
387	});	749	});
388		750
389	# request two	751	# request two, simply returns 64 octets
390	$handle->push_write ("request 2\015\012");	752	$handle->push_write ("request 2\015\012");
391		753
392	# simply read 64 bytes, always	754	# simply read 64 bytes, always
393	$handle->push_read_chunk (64, sub {	755	$handle->push_read (chunk => 64, sub {
394	my $response = $_[1];	756	my $response = $_[1];
395	...	757	...
396	});	758	});
397		759
398	=over 4	760	=over 4
399		761
400	=cut	762	=cut
401		763
402	sub _drain_rbuf {	764	sub _drain_rbuf {
403	my ($self) = @_;	765	my ($self) = @_;
		766
		767	local $self->{_in_drain} = 1;
404		768
405	if (	769	if (
406	defined $self->{rbuf_max}	770	defined $self->{rbuf_max}
407	&& $self->{rbuf_max} < length $self->{rbuf}	771	&& $self->{rbuf_max} < length $self->{rbuf}
408	) {	772	) {
409	$! = &Errno::ENOSPC; return $self->error;	773	$self->_error (&Errno::ENOSPC, 1), return;
410	}	774	}
411		775
412	return if $self->{in_drain};	776	while () {
413	local $self->{in_drain} = 1;
414
415	while (my $len = length $self->{rbuf}) {	777	my $len = length $self->{rbuf};
416	no strict 'refs';	778
417	if (my $cb = shift @{ $self->{queue} }) {	779	if (my $cb = shift @{ $self->{_queue} }) {
418	if (!$cb->($self)) {	780	unless ($cb->($self)) {
419	if ($self->{eof}) {	781	if ($self->{_eof}) {
420	# no progress can be made (not enough data and no data forthcoming)	782	# no progress can be made (not enough data and no data forthcoming)
421	$! = &Errno::EPIPE; return $self->error;	783	$self->_error (&Errno::EPIPE, 1), return;
422	}	784	}
423		785
424	unshift @{ $self->{queue} }, $cb;	786	unshift @{ $self->{_queue} }, $cb;
425	return;	787	last;
426	}	788	}
427	} elsif ($self->{on_read}) {	789	} elsif ($self->{on_read}) {
		790	last unless $len;
		791
428	$self->{on_read}($self);	792	$self->{on_read}($self);
429		793
430	if (	794	if (
431	$self->{eof} # if no further data will arrive
432	&& $len == length $self->{rbuf} # and no data has been consumed	795	$len == length $self->{rbuf} # if no data has been consumed
433	&& !@{ $self->{queue} } # and the queue is still empty	796	&& !@{ $self->{_queue} } # and the queue is still empty
434	&& $self->{on_read} # and we still want to read data	797	&& $self->{on_read} # but we still have on_read
435	) {	798	) {
		799	# no further data will arrive
436	# then no progress can be made	800	# so no progress can be made
437	$! = &Errno::EPIPE; return $self->error;	801	$self->_error (&Errno::EPIPE, 1), return
		802	if $self->{_eof};
		803
		804	last; # more data might arrive
438	}	805	}
439	} else {	806	} else {
440	# read side becomes idle	807	# read side becomes idle
441	delete $self->{rw};	808	delete $self->{_rw};
442	return;	809	last;
443	}	810	}
444	}	811	}
445		812
446	if ($self->{eof}) {	813	if ($self->{_eof}) {
447	$self->_shutdown;	814	if ($self->{on_eof}) {
448	$self->{on_eof}($self)	815	$self->{on_eof}($self)
449	if $self->{on_eof};	816	} else {
		817	$self->_error (0, 1);
		818	}
		819	}
		820
		821	# may need to restart read watcher
		822	unless ($self->{_rw}) {
		823	$self->start_read
		824	if $self->{on_read} || @{ $self->{_queue} };
450	}	825	}
451	}	826	}
452		827
453	=item $handle->on_read ($cb)	828	=item $handle->on_read ($cb)
454		829
…		…
460		835
461	sub on_read {	836	sub on_read {
462	my ($self, $cb) = @_;	837	my ($self, $cb) = @_;
463		838
464	$self->{on_read} = $cb;	839	$self->{on_read} = $cb;
		840	$self->_drain_rbuf if $cb && !$self->{_in_drain};
465	}	841	}
466		842
467	=item $handle->rbuf	843	=item $handle->rbuf
468		844
469	Returns the read buffer (as a modifiable lvalue).	845	Returns the read buffer (as a modifiable lvalue).
…		…
500	interested in (which can be none at all) and return a true value. After returning	876	interested in (which can be none at all) and return a true value. After returning
501	true, it will be removed from the queue.	877	true, it will be removed from the queue.
502		878
503	=cut	879	=cut
504		880
		881	our %RH;
		882
		883	sub register_read_type($$) {
		884	$RH{$_[0]} = $_[1];
		885	}
		886
505	sub push_read {	887	sub push_read {
506	my ($self, $cb) = @_;	888	my $self = shift;
		889	my $cb = pop;
507		890
		891	if (@_) {
		892	my $type = shift;
		893
		894	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		895	->($self, $cb, @_);
		896	}
		897
508	push @{ $self->{queue} }, $cb;	898	push @{ $self->{_queue} }, $cb;
509	$self->_drain_rbuf;	899	$self->_drain_rbuf unless $self->{_in_drain};
510	}	900	}
511		901
512	sub unshift_read {	902	sub unshift_read {
513	my ($self, $cb) = @_;	903	my $self = shift;
		904	my $cb = pop;
514		905
		906	if (@_) {
		907	my $type = shift;
		908
		909	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		910	->($self, $cb, @_);
		911	}
		912
		913
515	push @{ $self->{queue} }, $cb;	914	unshift @{ $self->{_queue} }, $cb;
516	$self->_drain_rbuf;	915	$self->_drain_rbuf unless $self->{_in_drain};
517	}	916	}
518		917
519	=item $handle->push_read_chunk ($len, $cb->($self, $data))	918	=item $handle->push_read (type => @args, $cb)
520		919
521	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	920	=item $handle->unshift_read (type => @args, $cb)
522		921
523	Append the given callback to the end of the queue (C<push_read_chunk>) or	922	Instead of providing a callback that parses the data itself you can chose
524	prepend it (C<unshift_read_chunk>).	923	between a number of predefined parsing formats, for chunks of data, lines
		924	etc.
525		925
526	The callback will be called only once C<$len> bytes have been read, and	926	Predefined types are (if you have ideas for additional types, feel free to
527	these C<$len> bytes will be passed to the callback.	927	drop by and tell us):
528		928
529	=cut	929	=over 4
530		930
531	sub _read_chunk($$) {	931	=item chunk => $octets, $cb->($handle, $data)
		932
		933	Invoke the callback only once C<$octets> bytes have been read. Pass the
		934	data read to the callback. The callback will never be called with less
		935	data.
		936
		937	Example: read 2 bytes.
		938
		939	$handle->push_read (chunk => 2, sub {
		940	warn "yay ", unpack "H*", $_[1];
		941	});
		942
		943	=cut
		944
		945	register_read_type chunk => sub {
532	my ($self, $len, $cb) = @_;	946	my ($self, $cb, $len) = @_;
533		947
534	sub {	948	sub {
535	$len <= length $_[0]{rbuf} or return;	949	$len <= length $_[0]{rbuf} or return;
536	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	950	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
537	1	951	1
538	}	952	}
539	}	953	};
540		954
541	sub push_read_chunk {	955	=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		956
557	The callback will be called only once a full line (including the end of	957	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	958	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	959	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>).	960	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	971	Partial lines at the end of the stream will never be returned, as they are
572	not marked by the end of line marker.	972	not marked by the end of line marker.
573		973
574	=cut	974	=cut
575		975
576	sub _read_line($$) {	976	register_read_type line => sub {
577	my $self = shift;	977	my ($self, $cb, $eol) = @_;
578	my $cb = pop;
579	my $eol = @_ ? shift : qr|(\015?\012)|;
580	my $pos;
581		978
		979	if (@_ < 3) {
		980	# this is more than twice as fast as the generic code below
		981	sub {
		982	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		983
		984	$cb->($_[0], $1, $2);
		985	1
		986	}
		987	} else {
582	$eol = quotemeta $eol unless ref $eol;	988	$eol = quotemeta $eol unless ref $eol;
583	$eol = qr|^(.*?)($eol)|s;	989	$eol = qr|^(.*?)($eol)|s;
		990
		991	sub {
		992	$_[0]{rbuf} =~ s/$eol// or return;
		993
		994	$cb->($_[0], $1, $2);
		995	1
		996	}
		997	}
		998	};
		999
		1000	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		1001
		1002	Makes a regex match against the regex object C<$accept> and returns
		1003	everything up to and including the match.
		1004
		1005	Example: read a single line terminated by '\n'.
		1006
		1007	$handle->push_read (regex => qr<\n>, sub { ... });
		1008
		1009	If C<$reject> is given and not undef, then it determines when the data is
		1010	to be rejected: it is matched against the data when the C<$accept> regex
		1011	does not match and generates an C<EBADMSG> error when it matches. This is
		1012	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1013	receive buffer overflow).
		1014
		1015	Example: expect a single decimal number followed by whitespace, reject
		1016	anything else (not the use of an anchor).
		1017
		1018	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1019
		1020	If C<$skip> is given and not C<undef>, then it will be matched against
		1021	the receive buffer when neither C<$accept> nor C<$reject> match,
		1022	and everything preceding and including the match will be accepted
		1023	unconditionally. This is useful to skip large amounts of data that you
		1024	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1025	have to start matching from the beginning. This is purely an optimisation
		1026	and is usually worth only when you expect more than a few kilobytes.
		1027
		1028	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1029	expect the header to be very large (it isn't in practise, but...), we use
		1030	a skip regex to skip initial portions. The skip regex is tricky in that
		1031	it only accepts something not ending in either \015 or \012, as these are
		1032	required for the accept regex.
		1033
		1034	$handle->push_read (regex =>
		1035	qr<\015\012\015\012>,
		1036	undef, # no reject
		1037	qr<^.*[^\015\012]>,
		1038	sub { ... });
		1039
		1040	=cut
		1041
		1042	register_read_type regex => sub {
		1043	my ($self, $cb, $accept, $reject, $skip) = @_;
		1044
		1045	my $data;
		1046	my $rbuf = \$self->{rbuf};
584		1047
585	sub {	1048	sub {
586	$_[0]{rbuf} =~ s/$eol// or return;	1049	# accept
		1050	if ($$rbuf =~ $accept) {
		1051	$data .= substr $$rbuf, 0, $+[0], "";
		1052	$cb->($self, $data);
		1053	return 1;
		1054	}
		1055
		1056	# reject
		1057	if ($reject && $$rbuf =~ $reject) {
		1058	$self->_error (&Errno::EBADMSG);
		1059	}
587		1060
588	$cb->($_[0], $1, $2);	1061	# skip
		1062	if ($skip && $$rbuf =~ $skip) {
		1063	$data .= substr $$rbuf, 0, $+[0], "";
		1064	}
		1065
		1066	()
		1067	}
		1068	};
		1069
		1070	=item netstring => $cb->($handle, $string)
		1071
		1072	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1073
		1074	Throws an error with C<$!> set to EBADMSG on format violations.
		1075
		1076	=cut
		1077
		1078	register_read_type netstring => sub {
		1079	my ($self, $cb) = @_;
		1080
		1081	sub {
		1082	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1083	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1084	$self->_error (&Errno::EBADMSG);
		1085	}
		1086	return;
		1087	}
		1088
		1089	my $len = $1;
		1090
		1091	$self->unshift_read (chunk => $len, sub {
		1092	my $string = $_[1];
		1093	$_[0]->unshift_read (chunk => 1, sub {
		1094	if ($_[1] eq ",") {
		1095	$cb->($_[0], $string);
		1096	} else {
		1097	$self->_error (&Errno::EBADMSG);
		1098	}
		1099	});
		1100	});
		1101
589	1	1102	1
590	}	1103	}
591	}	1104	};
592		1105
593	sub push_read_line {	1106	=item packstring => $format, $cb->($handle, $string)
594	$_[0]->push_read (&_read_line);
595	}
596		1107
597	sub unshift_read_line {	1108	An octet string prefixed with an encoded length. The encoding C<$format>
598	$_[0]->unshift_read (&_read_line);	1109	uses the same format as a Perl C<pack> format, but must specify a single
599	}	1110	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1111	optional C<!>, C<< < >> or C<< > >> modifier).
		1112
		1113	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.
		1114
		1115	Example: read a block of data prefixed by its length in BER-encoded
		1116	format (very efficient).
		1117
		1118	$handle->push_read (packstring => "w", sub {
		1119	my ($handle, $data) = @_;
		1120	});
		1121
		1122	=cut
		1123
		1124	register_read_type packstring => sub {
		1125	my ($self, $cb, $format) = @_;
		1126
		1127	sub {
		1128	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1129	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1130	or return;
		1131
		1132	$format = length pack $format, $len;
		1133
		1134	# bypass unshift if we already have the remaining chunk
		1135	if ($format + $len <= length $_[0]{rbuf}) {
		1136	my $data = substr $_[0]{rbuf}, $format, $len;
		1137	substr $_[0]{rbuf}, 0, $format + $len, "";
		1138	$cb->($_[0], $data);
		1139	} else {
		1140	# remove prefix
		1141	substr $_[0]{rbuf}, 0, $format, "";
		1142
		1143	# read remaining chunk
		1144	$_[0]->unshift_read (chunk => $len, $cb);
		1145	}
		1146
		1147	1
		1148	}
		1149	};
		1150
		1151	=item json => $cb->($handle, $hash_or_arrayref)
		1152
		1153	Reads a JSON object or array, decodes it and passes it to the callback.
		1154
		1155	If a C<json> object was passed to the constructor, then that will be used
		1156	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1157
		1158	This read type uses the incremental parser available with JSON version
		1159	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1160	dependency on your own: this module will load the JSON module, but
		1161	AnyEvent does not depend on it itself.
		1162
		1163	Since JSON texts are fully self-delimiting, the C<json> read and write
		1164	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1165	the C<json> write type description, above, for an actual example.
		1166
		1167	=cut
		1168
		1169	register_read_type json => sub {
		1170	my ($self, $cb) = @_;
		1171
		1172	require JSON;
		1173
		1174	my $data;
		1175	my $rbuf = \$self->{rbuf};
		1176
		1177	my $json = $self->{json} ||= JSON->new->utf8;
		1178
		1179	sub {
		1180	my $ref = $json->incr_parse ($self->{rbuf});
		1181
		1182	if ($ref) {
		1183	$self->{rbuf} = $json->incr_text;
		1184	$json->incr_text = "";
		1185	$cb->($self, $ref);
		1186
		1187	1
		1188	} else {
		1189	$self->{rbuf} = "";
		1190	()
		1191	}
		1192	}
		1193	};
		1194
		1195	=item storable => $cb->($handle, $ref)
		1196
		1197	Deserialises a L<Storable> frozen representation as written by the
		1198	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1199	data).
		1200
		1201	Raises C<EBADMSG> error if the data could not be decoded.
		1202
		1203	=cut
		1204
		1205	register_read_type storable => sub {
		1206	my ($self, $cb) = @_;
		1207
		1208	require Storable;
		1209
		1210	sub {
		1211	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1212	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1213	or return;
		1214
		1215	my $format = length pack "w", $len;
		1216
		1217	# bypass unshift if we already have the remaining chunk
		1218	if ($format + $len <= length $_[0]{rbuf}) {
		1219	my $data = substr $_[0]{rbuf}, $format, $len;
		1220	substr $_[0]{rbuf}, 0, $format + $len, "";
		1221	$cb->($_[0], Storable::thaw ($data));
		1222	} else {
		1223	# remove prefix
		1224	substr $_[0]{rbuf}, 0, $format, "";
		1225
		1226	# read remaining chunk
		1227	$_[0]->unshift_read (chunk => $len, sub {
		1228	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1229	$cb->($_[0], $ref);
		1230	} else {
		1231	$self->_error (&Errno::EBADMSG);
		1232	}
		1233	});
		1234	}
		1235
		1236	1
		1237	}
		1238	};
		1239
		1240	=back
		1241
		1242	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1243
		1244	This function (not method) lets you add your own types to C<push_read>.
		1245
		1246	Whenever the given C<type> is used, C<push_read> will invoke the code
		1247	reference with the handle object, the callback and the remaining
		1248	arguments.
		1249
		1250	The code reference is supposed to return a callback (usually a closure)
		1251	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1252
		1253	It should invoke the passed callback when it is done reading (remember to
		1254	pass C<$handle> as first argument as all other callbacks do that).
		1255
		1256	Note that this is a function, and all types registered this way will be
		1257	global, so try to use unique names.
		1258
		1259	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1260	search for C<register_read_type>)).
600		1261
601	=item $handle->stop_read	1262	=item $handle->stop_read
602		1263
603	=item $handle->start_read	1264	=item $handle->start_read
604		1265
605	In rare cases you actually do not want to read anything from the	1266	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	1267	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	1268	any queued callbacks will be executed then. To start reading again, call
608	C<start_read>.	1269	C<start_read>.
		1270
		1271	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1272	you change the C<on_read> callback or push/unshift a read callback, and it
		1273	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1274	there are any read requests in the queue.
609		1275
610	=cut	1276	=cut
611		1277
612	sub stop_read {	1278	sub stop_read {
613	my ($self) = @_;	1279	my ($self) = @_;
614		1280
615	delete $self->{rw};	1281	delete $self->{_rw};
616	}	1282	}
617		1283
618	sub start_read {	1284	sub start_read {
619	my ($self) = @_;	1285	my ($self) = @_;
620		1286
621	unless ($self->{rw} || $self->{eof}) {	1287	unless ($self->{_rw} || $self->{_eof}) {
622	Scalar::Util::weaken $self;	1288	Scalar::Util::weaken $self;
623		1289
624	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1290	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
625	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1291	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
626	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1292	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
627		1293
628	if ($len > 0) {	1294	if ($len > 0) {
		1295	$self->{_activity} = AnyEvent->now;
		1296
629	$self->{filter_r}	1297	$self->{filter_r}
630	? $self->{filter_r}->($self, $rbuf)	1298	? $self->{filter_r}($self, $rbuf)
631	: $self->_drain_rbuf;	1299	: $self->{_in_drain} || $self->_drain_rbuf;
632		1300
633	} elsif (defined $len) {	1301	} elsif (defined $len) {
634	delete $self->{rw};	1302	delete $self->{_rw};
635	$self->{eof} = 1;	1303	$self->{_eof} = 1;
636	$self->_drain_rbuf;	1304	$self->_drain_rbuf unless $self->{_in_drain};
637		1305
638	} elsif ($! != EAGAIN && $! != EINTR) {	1306	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
639	return $self->error;	1307	return $self->_error ($!, 1);
640	}	1308	}
641	});	1309	});
642	}	1310	}
643	}	1311	}
644		1312
645	sub _dotls {	1313	sub _dotls {
646	my ($self) = @_;	1314	my ($self) = @_;
647		1315
		1316	my $buf;
		1317
648	if (length $self->{tls_wbuf}) {	1318	if (length $self->{_tls_wbuf}) {
649	my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf});	1319	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
650	substr $self->{tls_wbuf}, 0, $len, "" if $len > 0;	1320	substr $self->{_tls_wbuf}, 0, $len, "";
		1321	}
651	}	1322	}
652		1323
		1324	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
		1325	unless (length $buf) {
		1326	# let's treat SSL-eof as we treat normal EOF
		1327	delete $self->{_rw};
		1328	$self->{_eof} = 1;
		1329	&_freetls;
		1330	}
		1331
		1332	$self->{rbuf} .= $buf;
		1333	$self->_drain_rbuf unless $self->{_in_drain};
		1334	$self->{tls} or return; # tls session might have gone away in callback
		1335	}
		1336
		1337	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1338
		1339	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1340	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1341	return $self->_error ($!, 1);
		1342	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1343	return $self->_error (&Errno::EIO, 1);
		1344	}
		1345
		1346	# all others are fine for our purposes
		1347	}
		1348
653	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) {	1349	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
654	$self->{wbuf} .= $buf;	1350	$self->{wbuf} .= $buf;
655	$self->_drain_wbuf;	1351	$self->_drain_wbuf;
656	}	1352	}
657
658	if (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
659	$self->{rbuf} .= $buf;
660	$self->_drain_rbuf;
661	} elsif (
662	(my $err = Net::SSLeay::get_error ($self->{tls}, -1))
663	!= Net::SSLeay::ERROR_WANT_READ ()
664	) {
665	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
666	$self->error;
667	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
668	$! = &Errno::EIO;
669	$self->error;
670	}
671
672	# all others are fine for our purposes
673	}
674	}	1353	}
675		1354
676	# TODO: maybe document...	1355	=item $handle->starttls ($tls[, $tls_ctx])
		1356
		1357	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1358	object is created, you can also do that at a later time by calling
		1359	C<starttls>.
		1360
		1361	The first argument is the same as the C<tls> constructor argument (either
		1362	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1363
		1364	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1365	used when AnyEvent::Handle has to create its own TLS connection object.
		1366
		1367	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1368	call and can be used or changed to your liking. Note that the handshake
		1369	might have already started when this function returns.
		1370
		1371	If it an error to start a TLS handshake more than once per
		1372	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1373
		1374	=cut
		1375
677	sub starttls {	1376	sub starttls {
678	my ($self, $ssl, $ctx) = @_;	1377	my ($self, $ssl, $ctx) = @_;
679		1378
		1379	Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object"
		1380	if $self->{tls};
		1381
680	if ($ssl eq "accept") {	1382	if ($ssl eq "accept") {
681	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1383	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
682	Net::SSLeay::set_accept_state ($ssl);	1384	Net::SSLeay::set_accept_state ($ssl);
683	} elsif ($ssl eq "connect") {	1385	} elsif ($ssl eq "connect") {
684	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1386	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
685	Net::SSLeay::set_connect_state ($ssl);	1387	Net::SSLeay::set_connect_state ($ssl);
686	}	1388	}
687		1389
688	$self->{tls} = $ssl;	1390	$self->{tls} = $ssl;
689		1391
		1392	# basically, this is deep magic (because SSL_read should have the same issues)
		1393	# but the openssl maintainers basically said: "trust us, it just works".
		1394	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1395	# and mismaintained ssleay-module doesn't even offer them).
		1396	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1397	#
		1398	# in short: this is a mess.
		1399	#
		1400	# note that we do not try to kepe the length constant between writes as we are required to do.
		1401	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1402	# and we drive openssl fully in blocking mode here.
		1403	Net::SSLeay::CTX_set_mode ($self->{tls},
		1404	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1405	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1406
690	$self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1407	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
691	$self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1408	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
692		1409
693	Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio});	1410	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
694		1411
695	$self->{filter_w} = sub {	1412	$self->{filter_w} = sub {
696	$_[0]{tls_wbuf} .= ${$_[1]};	1413	$_[0]{_tls_wbuf} .= ${$_[1]};
697	&_dotls;	1414	&_dotls;
698	};	1415	};
699	$self->{filter_r} = sub {	1416	$self->{filter_r} = sub {
700	Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});	1417	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
701	&_dotls;	1418	&_dotls;
702	};	1419	};
		1420
		1421	&_dotls; # need to trigger the initial negotiation exchange
		1422	}
		1423
		1424	=item $handle->stoptls
		1425
		1426	Shuts down the SSL connection - this makes a proper EOF handshake by
		1427	sending a close notify to the other side, but since OpenSSL doesn't
		1428	support non-blocking shut downs, it is not possible to re-use the stream
		1429	afterwards.
		1430
		1431	=cut
		1432
		1433	sub stoptls {
		1434	my ($self) = @_;
		1435
		1436	if ($self->{tls}) {
		1437	Net::SSLeay::shutdown $self->{tls};
		1438
		1439	&_dotls;
		1440
		1441	# we don't give a shit. no, we do, but we can't. no...
		1442	# we, we... have to use openssl :/
		1443	&_freetls;
		1444	}
		1445	}
		1446
		1447	sub _freetls {
		1448	my ($self) = @_;
		1449
		1450	return unless $self->{tls};
		1451
		1452	Net::SSLeay::free (delete $self->{tls});
		1453
		1454	delete @$self{qw(_rbio filter_w _wbio filter_r)};
703	}	1455	}
704		1456
705	sub DESTROY {	1457	sub DESTROY {
706	my $self = shift;	1458	my $self = shift;
707		1459
708	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1460	&_freetls;
		1461
		1462	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1463
		1464	if ($linger && length $self->{wbuf}) {
		1465	my $fh = delete $self->{fh};
		1466	my $wbuf = delete $self->{wbuf};
		1467
		1468	my @linger;
		1469
		1470	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1471	my $len = syswrite $fh, $wbuf, length $wbuf;
		1472
		1473	if ($len > 0) {
		1474	substr $wbuf, 0, $len, "";
		1475	} else {
		1476	@linger = (); # end
		1477	}
		1478	});
		1479	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1480	@linger = ();
		1481	});
		1482	}
709	}	1483	}
710		1484
711	=item AnyEvent::Handle::TLS_CTX	1485	=item AnyEvent::Handle::TLS_CTX
712		1486
713	This function creates and returns the Net::SSLeay::CTX object used by	1487	This function creates and returns the Net::SSLeay::CTX object used by
…		…
743	}	1517	}
744	}	1518	}
745		1519
746	=back	1520	=back
747		1521
		1522	=head1 SUBCLASSING AnyEvent::Handle
		1523
		1524	In many cases, you might want to subclass AnyEvent::Handle.
		1525
		1526	To make this easier, a given version of AnyEvent::Handle uses these
		1527	conventions:
		1528
		1529	=over 4
		1530
		1531	=item * all constructor arguments become object members.
		1532
		1533	At least initially, when you pass a C<tls>-argument to the constructor it
		1534	will end up in C<< $handle->{tls} >>. Those members might be changed or
		1535	mutated later on (for example C<tls> will hold the TLS connection object).
		1536
		1537	=item * other object member names are prefixed with an C<_>.
		1538
		1539	All object members not explicitly documented (internal use) are prefixed
		1540	with an underscore character, so the remaining non-C<_>-namespace is free
		1541	for use for subclasses.
		1542
		1543	=item * all members not documented here and not prefixed with an underscore
		1544	are free to use in subclasses.
		1545
		1546	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1547	member variables, but thats just life, at least it is documented.
		1548
		1549	=back
		1550
748	=head1 AUTHOR	1551	=head1 AUTHOR
749		1552
750	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	1553	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
751		1554
752	=cut	1555	=cut

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