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Revision 1.38 by root, Mon May 26 21:28:33 2008 UTC vs.
Revision 1.109 by root, Wed Jan 14 02:03:43 2009 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 qw(WSAWOULDBLOCK);	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 file handles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16		16
17	=cut	17	=cut
18		18
19	our $VERSION = '0.04';	19	our $VERSION = 4.331;
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
…		…
27		27
28	my $handle =	28	my $handle =
29	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
30	fh => \*STDIN,	30	fh => \*STDIN,
31	on_eof => sub {	31	on_eof => sub {
32	$cv->broadcast;	32	$cv->send;
33	},	33	},
34	);	34	);
35		35
36	# send some request line	36	# send some request line
37	$handle->push_write ("getinfo\015\012");	37	$handle->push_write ("getinfo\015\012");
…		…
49		49
50	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
51	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
52	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
53		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
54	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
55	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
56	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
57		60
58	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
…		…
70		73
71	=item fh => $filehandle [MANDATORY]	74	=item fh => $filehandle [MANDATORY]
72		75
73	The filehandle this L<AnyEvent::Handle> object will operate on.	76	The filehandle this L<AnyEvent::Handle> object will operate on.
74		77
75	NOTE: The filehandle will be set to non-blocking (using	78	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
77		81
78	=item on_eof => $cb->($self)	82	=item on_eof => $cb->($handle)
79		83
80	Set the callback to be called on EOF.	84	Set the callback to be called when an end-of-file condition is detected,
		85	i.e. in the case of a socket, when the other side has closed the
		86	connection cleanly.
81		87
		88	For sockets, this just means that the other side has stopped sending data,
		89	you can still try to write data, and, in fact, one can return from the EOF
		90	callback and continue writing data, as only the read part has been shut
		91	down.
		92
82	While not mandatory, it is highly recommended to set an eof callback,	93	While not mandatory, it is I<highly> recommended to set an EOF callback,
83	otherwise you might end up with a closed socket while you are still	94	otherwise you might end up with a closed socket while you are still
84	waiting for data.	95	waiting for data.
85		96
		97	If an EOF condition has been detected but no C<on_eof> callback has been
		98	set, then a fatal error will be raised with C<$!> set to <0>.
		99
86	=item on_error => $cb->($self)	100	=item on_error => $cb->($handle, $fatal)
87		101
88	This is the fatal error callback, that is called when, well, a fatal error	102	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	103	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	104	connect or a read error.
91		105
92	The object will not be in a usable state when this callback has been	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	107	fatal errors the handle object will be shut down and will not be usable
		108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		109	errors are an EOF condition with active (but unsatisifable) read watchers
		110	(C<EPIPE>) or I/O errors.
		111
		112	Non-fatal errors can be retried by simply returning, but it is recommended
		113	to simply ignore this parameter and instead abondon the handle object
		114	when this callback is invoked. Examples of non-fatal errors are timeouts
		115	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
94		116
95	On callback entrance, the value of C<$!> contains the operating system	117	On callback entrance, the value of C<$!> contains the operating system
96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).	118	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
97
98	The callback should throw an exception. If it returns, then
99	AnyEvent::Handle will C<croak> for you.
100		119
101	While not mandatory, it is I<highly> recommended to set this callback, as	120	While not mandatory, it is I<highly> recommended to set this callback, as
102	you will not be notified of errors otherwise. The default simply calls	121	you will not be notified of errors otherwise. The default simply calls
103	die.	122	C<croak>.
104		123
105	=item on_read => $cb->($self)	124	=item on_read => $cb->($handle)
106		125
107	This sets the default read callback, which is called when data arrives	126	This sets the default read callback, which is called when data arrives
108	and no read request is in the queue.	127	and no read request is in the queue (unlike read queue callbacks, this
		128	callback will only be called when at least one octet of data is in the
		129	read buffer).
109		130
110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	131	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111	method or access the C<$self->{rbuf}> member directly.	132	method or access the C<$handle->{rbuf}> member directly.
112		133
113	When an EOF condition is detected then AnyEvent::Handle will first try to	134	When an EOF condition is detected then AnyEvent::Handle will first try to
114	feed all the remaining data to the queued callbacks and C<on_read> before	135	feed all the remaining data to the queued callbacks and C<on_read> before
115	calling the C<on_eof> callback. If no progress can be made, then a fatal	136	calling the C<on_eof> callback. If no progress can be made, then a fatal
116	error will be raised (with C<$!> set to C<EPIPE>).	137	error will be raised (with C<$!> set to C<EPIPE>).
117		138
118	=item on_drain => $cb->()	139	=item on_drain => $cb->($handle)
119		140
120	This sets the callback that is called when the write buffer becomes empty	141	This sets the callback that is called when the write buffer becomes empty
121	(or when the callback is set and the buffer is empty already).	142	(or when the callback is set and the buffer is empty already).
122		143
123	To append to the write buffer, use the C<< ->push_write >> method.	144	To append to the write buffer, use the C<< ->push_write >> method.
124		145
		146	This callback is useful when you don't want to put all of your write data
		147	into the queue at once, for example, when you want to write the contents
		148	of some file to the socket you might not want to read the whole file into
		149	memory and push it into the queue, but instead only read more data from
		150	the file when the write queue becomes empty.
		151
		152	=item timeout => $fractional_seconds
		153
		154	If non-zero, then this enables an "inactivity" timeout: whenever this many
		155	seconds pass without a successful read or write on the underlying file
		156	handle, the C<on_timeout> callback will be invoked (and if that one is
		157	missing, a non-fatal C<ETIMEDOUT> error will be raised).
		158
		159	Note that timeout processing is also active when you currently do not have
		160	any outstanding read or write requests: If you plan to keep the connection
		161	idle then you should disable the timout temporarily or ignore the timeout
		162	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		163	restart the timeout.
		164
		165	Zero (the default) disables this timeout.
		166
		167	=item on_timeout => $cb->($handle)
		168
		169	Called whenever the inactivity timeout passes. If you return from this
		170	callback, then the timeout will be reset as if some activity had happened,
		171	so this condition is not fatal in any way.
		172
125	=item rbuf_max => <bytes>	173	=item rbuf_max => <bytes>
126		174
127	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	175	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128	when the read buffer ever (strictly) exceeds this size. This is useful to	176	when the read buffer ever (strictly) exceeds this size. This is useful to
129	avoid denial-of-service attacks.	177	avoid some forms of denial-of-service attacks.
130		178
131	For example, a server accepting connections from untrusted sources should	179	For example, a server accepting connections from untrusted sources should
132	be configured to accept only so-and-so much data that it cannot act on	180	be configured to accept only so-and-so much data that it cannot act on
133	(for example, when expecting a line, an attacker could send an unlimited	181	(for example, when expecting a line, an attacker could send an unlimited
134	amount of data without a callback ever being called as long as the line	182	amount of data without a callback ever being called as long as the line
135	isn't finished).	183	isn't finished).
136		184
		185	=item autocork => <boolean>
		186
		187	When disabled (the default), then C<push_write> will try to immediately
		188	write the data to the handle, if possible. This avoids having to register
		189	a write watcher and wait for the next event loop iteration, but can
		190	be inefficient if you write multiple small chunks (on the wire, this
		191	disadvantage is usually avoided by your kernel's nagle algorithm, see
		192	C<no_delay>, but this option can save costly syscalls).
		193
		194	When enabled, then writes will always be queued till the next event loop
		195	iteration. This is efficient when you do many small writes per iteration,
		196	but less efficient when you do a single write only per iteration (or when
		197	the write buffer often is full). It also increases write latency.
		198
		199	=item no_delay => <boolean>
		200
		201	When doing small writes on sockets, your operating system kernel might
		202	wait a bit for more data before actually sending it out. This is called
		203	the Nagle algorithm, and usually it is beneficial.
		204
		205	In some situations you want as low a delay as possible, which can be
		206	accomplishd by setting this option to a true value.
		207
		208	The default is your opertaing system's default behaviour (most likely
		209	enabled), this option explicitly enables or disables it, if possible.
		210
137	=item read_size => <bytes>	211	=item read_size => <bytes>
138		212
139	The default read block size (the amount of bytes this module will try to read	213	The default read block size (the amount of bytes this module will
140	on each [loop iteration). Default: C<4096>.	214	try to read during each loop iteration, which affects memory
		215	requirements). Default: C<8192>.
141		216
142	=item low_water_mark => <bytes>	217	=item low_water_mark => <bytes>
143		218
144	Sets the amount of bytes (default: C<0>) that make up an "empty" write	219	Sets the amount of bytes (default: C<0>) that make up an "empty" write
145	buffer: If the write reaches this size or gets even samller it is	220	buffer: If the write reaches this size or gets even samller it is
146	considered empty.	221	considered empty.
147		222
		223	Sometimes it can be beneficial (for performance reasons) to add data to
		224	the write buffer before it is fully drained, but this is a rare case, as
		225	the operating system kernel usually buffers data as well, so the default
		226	is good in almost all cases.
		227
		228	=item linger => <seconds>
		229
		230	If non-zero (default: C<3600>), then the destructor of the
		231	AnyEvent::Handle object will check whether there is still outstanding
		232	write data and will install a watcher that will write this data to the
		233	socket. No errors will be reported (this mostly matches how the operating
		234	system treats outstanding data at socket close time).
		235
		236	This will not work for partial TLS data that could not be encoded
		237	yet. This data will be lost. Calling the C<stoptls> method in time might
		238	help.
		239
148	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	240	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149		241
150	When this parameter is given, it enables TLS (SSL) mode, that means it	242	When this parameter is given, it enables TLS (SSL) mode, that means
151	will start making tls handshake and will transparently encrypt/decrypt	243	AnyEvent will start a TLS handshake as soon as the conenction has been
152	data.	244	established and will transparently encrypt/decrypt data afterwards.
153		245
154	TLS mode requires Net::SSLeay to be installed (it will be loaded	246	TLS mode requires Net::SSLeay to be installed (it will be loaded
155	automatically when you try to create a TLS handle).	247	automatically when you try to create a TLS handle): this module doesn't
		248	have a dependency on that module, so if your module requires it, you have
		249	to add the dependency yourself.
156		250
157	For the TLS server side, use C<accept>, and for the TLS client side of a	251	Unlike TCP, TLS has a server and client side: for the TLS server side, use
158	connection, use C<connect> mode.	252	C<accept>, and for the TLS client side of a connection, use C<connect>
		253	mode.
159		254
160	You can also provide your own TLS connection object, but you have	255	You can also provide your own TLS connection object, but you have
161	to make sure that you call either C<Net::SSLeay::set_connect_state>	256	to make sure that you call either C<Net::SSLeay::set_connect_state>
162	or C<Net::SSLeay::set_accept_state> on it before you pass it to	257	or C<Net::SSLeay::set_accept_state> on it before you pass it to
163	AnyEvent::Handle.	258	AnyEvent::Handle.
164		259
		260	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		261	passing in the wrong integer will lead to certain crash. This most often
		262	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		263	segmentation fault.
		264
165	See the C<starttls> method if you need to start TLs negotiation later.	265	See the C<< ->starttls >> method for when need to start TLS negotiation later.
166		266
167	=item tls_ctx => $ssl_ctx	267	=item tls_ctx => $ssl_ctx
168		268
169	Use the given Net::SSLeay::CTX object to create the new TLS connection	269	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
170	(unless a connection object was specified directly). If this parameter is	270	(unless a connection object was specified directly). If this parameter is
171	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	271	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172		272
173	=item filter_r => $cb	273	=item json => JSON or JSON::XS object
174		274
175	=item filter_w => $cb	275	This is the json coder object used by the C<json> read and write types.
176		276
177	These exist, but are undocumented at this time.	277	If you don't supply it, then AnyEvent::Handle will create and use a
		278	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		279	texts.
		280
		281	Note that you are responsible to depend on the JSON module if you want to
		282	use this functionality, as AnyEvent does not have a dependency itself.
178		283
179	=back	284	=back
180		285
181	=cut	286	=cut
182		287
…		…
187		292
188	$self->{fh} or Carp::croak "mandatory argument fh is missing";	293	$self->{fh} or Carp::croak "mandatory argument fh is missing";
189		294
190	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	295	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
191		296
192	if ($self->{tls}) {
193	require Net::SSLeay;
194	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	297	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
195	}	298	if $self->{tls};
196		299
197	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};	300	$self->{_activity} = AnyEvent->now;
198	$self->on_error (delete $self->{on_error}) if $self->{on_error};	301	$self->_timeout;
		302
199	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	303	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
200	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	304	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
201		305
202	$self->start_read;	306	$self->start_read
		307	if $self->{on_read};
203		308
204	$self	309	$self
205	}	310	}
206		311
207	sub _shutdown {	312	sub _shutdown {
208	my ($self) = @_;	313	my ($self) = @_;
209		314
		315	delete $self->{_tw};
210	delete $self->{_rw};	316	delete $self->{_rw};
211	delete $self->{_ww};	317	delete $self->{_ww};
212	delete $self->{fh};	318	delete $self->{fh};
213	}
214		319
		320	&_freetls;
		321
		322	delete $self->{on_read};
		323	delete $self->{_queue};
		324	}
		325
215	sub error {	326	sub _error {
216	my ($self) = @_;	327	my ($self, $errno, $fatal) = @_;
217		328
218	{
219	local $!;
220	$self->_shutdown;	329	$self->_shutdown
221	}	330	if $fatal;
222		331
223	$self->{on_error}($self)	332	$! = $errno;
		333
224	if $self->{on_error};	334	if ($self->{on_error}) {
225		335	$self->{on_error}($self, $fatal);
		336	} elsif ($self->{fh}) {
226	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	337	Carp::croak "AnyEvent::Handle uncaught error: $!";
		338	}
227	}	339	}
228		340
229	=item $fh = $handle->fh	341	=item $fh = $handle->fh
230		342
231	This method returns the file handle of the L<AnyEvent::Handle> object.	343	This method returns the file handle used to create the L<AnyEvent::Handle> object.
232		344
233	=cut	345	=cut
234		346
235	sub fh { $_[0]{fh} }	347	sub fh { $_[0]{fh} }
236		348
…		…
252		364
253	sub on_eof {	365	sub on_eof {
254	$_[0]{on_eof} = $_[1];	366	$_[0]{on_eof} = $_[1];
255	}	367	}
256		368
		369	=item $handle->on_timeout ($cb)
		370
		371	Replace the current C<on_timeout> callback, or disables the callback (but
		372	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
		373	argument and method.
		374
		375	=cut
		376
		377	sub on_timeout {
		378	$_[0]{on_timeout} = $_[1];
		379	}
		380
		381	=item $handle->autocork ($boolean)
		382
		383	Enables or disables the current autocork behaviour (see C<autocork>
		384	constructor argument). Changes will only take effect on the next write.
		385
		386	=cut
		387
		388	sub autocork {
		389	$_[0]{autocork} = $_[1];
		390	}
		391
		392	=item $handle->no_delay ($boolean)
		393
		394	Enables or disables the C<no_delay> setting (see constructor argument of
		395	the same name for details).
		396
		397	=cut
		398
		399	sub no_delay {
		400	$_[0]{no_delay} = $_[1];
		401
		402	eval {
		403	local $SIG{__DIE__};
		404	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		405	};
		406	}
		407
		408	#############################################################################
		409
		410	=item $handle->timeout ($seconds)
		411
		412	Configures (or disables) the inactivity timeout.
		413
		414	=cut
		415
		416	sub timeout {
		417	my ($self, $timeout) = @_;
		418
		419	$self->{timeout} = $timeout;
		420	$self->_timeout;
		421	}
		422
		423	# reset the timeout watcher, as neccessary
		424	# also check for time-outs
		425	sub _timeout {
		426	my ($self) = @_;
		427
		428	if ($self->{timeout}) {
		429	my $NOW = AnyEvent->now;
		430
		431	# when would the timeout trigger?
		432	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		433
		434	# now or in the past already?
		435	if ($after <= 0) {
		436	$self->{_activity} = $NOW;
		437
		438	if ($self->{on_timeout}) {
		439	$self->{on_timeout}($self);
		440	} else {
		441	$self->_error (&Errno::ETIMEDOUT);
		442	}
		443
		444	# callback could have changed timeout value, optimise
		445	return unless $self->{timeout};
		446
		447	# calculate new after
		448	$after = $self->{timeout};
		449	}
		450
		451	Scalar::Util::weaken $self;
		452	return unless $self; # ->error could have destroyed $self
		453
		454	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		455	delete $self->{_tw};
		456	$self->_timeout;
		457	});
		458	} else {
		459	delete $self->{_tw};
		460	}
		461	}
		462
257	#############################################################################	463	#############################################################################
258		464
259	=back	465	=back
260		466
261	=head2 WRITE QUEUE	467	=head2 WRITE QUEUE
…		…
282	my ($self, $cb) = @_;	488	my ($self, $cb) = @_;
283		489
284	$self->{on_drain} = $cb;	490	$self->{on_drain} = $cb;
285		491
286	$cb->($self)	492	$cb->($self)
287	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	493	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
288	}	494	}
289		495
290	=item $handle->push_write ($data)	496	=item $handle->push_write ($data)
291		497
292	Queues the given scalar to be written. You can push as much data as you	498	Queues the given scalar to be written. You can push as much data as you
…		…
306	my $len = syswrite $self->{fh}, $self->{wbuf};	512	my $len = syswrite $self->{fh}, $self->{wbuf};
307		513
308	if ($len >= 0) {	514	if ($len >= 0) {
309	substr $self->{wbuf}, 0, $len, "";	515	substr $self->{wbuf}, 0, $len, "";
310		516
		517	$self->{_activity} = AnyEvent->now;
		518
311	$self->{on_drain}($self)	519	$self->{on_drain}($self)
312	if $self->{low_water_mark} >= length $self->{wbuf}	520	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
313	&& $self->{on_drain};	521	&& $self->{on_drain};
314		522
315	delete $self->{_ww} unless length $self->{wbuf};	523	delete $self->{_ww} unless length $self->{wbuf};
316	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) {	524	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
317	$self->error;	525	$self->_error ($!, 1);
318	}	526	}
319	};	527	};
320		528
321	# try to write data immediately	529	# try to write data immediately
322	$cb->();	530	$cb->() unless $self->{autocork};
323		531
324	# if still data left in wbuf, we need to poll	532	# if still data left in wbuf, we need to poll
325	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	533	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
326	if length $self->{wbuf};	534	if length $self->{wbuf};
327	};	535	};
…		…
341		549
342	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	550	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
343	->($self, @_);	551	->($self, @_);
344	}	552	}
345		553
346	if ($self->{filter_w}) {	554	if ($self->{tls}) {
347	$self->{filter_w}->($self, \$_[0]);	555	$self->{_tls_wbuf} .= $_[0];
		556
		557	&_dotls ($self);
348	} else {	558	} else {
349	$self->{wbuf} .= $_[0];	559	$self->{wbuf} .= $_[0];
350	$self->_drain_wbuf;	560	$self->_drain_wbuf;
351	}	561	}
352	}	562	}
353		563
354	=item $handle->push_write (type => @args)	564	=item $handle->push_write (type => @args)
355		565
356	=item $handle->unshift_write (type => @args)
357
358	Instead of formatting your data yourself, you can also let this module do	566	Instead of formatting your data yourself, you can also let this module do
359	the job by specifying a type and type-specific arguments.	567	the job by specifying a type and type-specific arguments.
360		568
361	Predefined types are (if you have ideas for additional types, feel free to	569	Predefined types are (if you have ideas for additional types, feel free to
362	drop by and tell us):	570	drop by and tell us):
…		…
366	=item netstring => $string	574	=item netstring => $string
367		575
368	Formats the given value as netstring	576	Formats the given value as netstring
369	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	577	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
370		578
371	=back
372
373	=cut	579	=cut
374		580
375	register_write_type netstring => sub {	581	register_write_type netstring => sub {
376	my ($self, $string) = @_;	582	my ($self, $string) = @_;
377		583
378	sprintf "%d:%s,", (length $string), $string	584	(length $string) . ":$string,"
379	};	585	};
380		586
		587	=item packstring => $format, $data
		588
		589	An octet string prefixed with an encoded length. The encoding C<$format>
		590	uses the same format as a Perl C<pack> format, but must specify a single
		591	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		592	optional C<!>, C<< < >> or C<< > >> modifier).
		593
		594	=cut
		595
		596	register_write_type packstring => sub {
		597	my ($self, $format, $string) = @_;
		598
		599	pack "$format/a*", $string
		600	};
		601
		602	=item json => $array_or_hashref
		603
		604	Encodes the given hash or array reference into a JSON object. Unless you
		605	provide your own JSON object, this means it will be encoded to JSON text
		606	in UTF-8.
		607
		608	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		609	one end of a handle and read them at the other end without using any
		610	additional framing.
		611
		612	The generated JSON text is guaranteed not to contain any newlines: While
		613	this module doesn't need delimiters after or between JSON texts to be
		614	able to read them, many other languages depend on that.
		615
		616	A simple RPC protocol that interoperates easily with others is to send
		617	JSON arrays (or objects, although arrays are usually the better choice as
		618	they mimic how function argument passing works) and a newline after each
		619	JSON text:
		620
		621	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		622	$handle->push_write ("\012");
		623
		624	An AnyEvent::Handle receiver would simply use the C<json> read type and
		625	rely on the fact that the newline will be skipped as leading whitespace:
		626
		627	$handle->push_read (json => sub { my $array = $_[1]; ... });
		628
		629	Other languages could read single lines terminated by a newline and pass
		630	this line into their JSON decoder of choice.
		631
		632	=cut
		633
		634	register_write_type json => sub {
		635	my ($self, $ref) = @_;
		636
		637	require JSON;
		638
		639	$self->{json} ? $self->{json}->encode ($ref)
		640	: JSON::encode_json ($ref)
		641	};
		642
		643	=item storable => $reference
		644
		645	Freezes the given reference using L<Storable> and writes it to the
		646	handle. Uses the C<nfreeze> format.
		647
		648	=cut
		649
		650	register_write_type storable => sub {
		651	my ($self, $ref) = @_;
		652
		653	require Storable;
		654
		655	pack "w/a*", Storable::nfreeze ($ref)
		656	};
		657
		658	=back
		659
381	=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args)	660	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
382		661
383	This function (not method) lets you add your own types to C<push_write>.	662	This function (not method) lets you add your own types to C<push_write>.
384	Whenever the given C<type> is used, C<push_write> will invoke the code	663	Whenever the given C<type> is used, C<push_write> will invoke the code
385	reference with the handle object and the remaining arguments.	664	reference with the handle object and the remaining arguments.
386		665
…		…
405	ways, the "simple" way, using only C<on_read> and the "complex" way, using	684	ways, the "simple" way, using only C<on_read> and the "complex" way, using
406	a queue.	685	a queue.
407		686
408	In the simple case, you just install an C<on_read> callback and whenever	687	In the simple case, you just install an C<on_read> callback and whenever
409	new data arrives, it will be called. You can then remove some data (if	688	new data arrives, it will be called. You can then remove some data (if
410	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	689	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
411	or not.	690	leave the data there if you want to accumulate more (e.g. when only a
		691	partial message has been received so far).
412		692
413	In the more complex case, you want to queue multiple callbacks. In this	693	In the more complex case, you want to queue multiple callbacks. In this
414	case, AnyEvent::Handle will call the first queued callback each time new	694	case, AnyEvent::Handle will call the first queued callback each time new
415	data arrives and removes it when it has done its job (see C<push_read>,	695	data arrives (also the first time it is queued) and removes it when it has
416	below).	696	done its job (see C<push_read>, below).
417		697
418	This way you can, for example, push three line-reads, followed by reading	698	This way you can, for example, push three line-reads, followed by reading
419	a chunk of data, and AnyEvent::Handle will execute them in order.	699	a chunk of data, and AnyEvent::Handle will execute them in order.
420		700
421	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	701	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
422	the specified number of bytes which give an XML datagram.	702	the specified number of bytes which give an XML datagram.
423		703
424	# in the default state, expect some header bytes	704	# in the default state, expect some header bytes
425	$handle->on_read (sub {	705	$handle->on_read (sub {
426	# some data is here, now queue the length-header-read (4 octets)	706	# some data is here, now queue the length-header-read (4 octets)
427	shift->unshift_read_chunk (4, sub {	707	shift->unshift_read (chunk => 4, sub {
428	# header arrived, decode	708	# header arrived, decode
429	my $len = unpack "N", $_[1];	709	my $len = unpack "N", $_[1];
430		710
431	# now read the payload	711	# now read the payload
432	shift->unshift_read_chunk ($len, sub {	712	shift->unshift_read (chunk => $len, sub {
433	my $xml = $_[1];	713	my $xml = $_[1];
434	# handle xml	714	# handle xml
435	});	715	});
436	});	716	});
437	});	717	});
438		718
439	Example 2: Implement a client for a protocol that replies either with	719	Example 2: Implement a client for a protocol that replies either with "OK"
440	"OK" and another line or "ERROR" for one request, and 64 bytes for the	720	and another line or "ERROR" for the first request that is sent, and 64
441	second request. Due tot he availability of a full queue, we can just	721	bytes for the second request. Due to the availability of a queue, we can
442	pipeline sending both requests and manipulate the queue as necessary in	722	just pipeline sending both requests and manipulate the queue as necessary
443	the callbacks:	723	in the callbacks.
444		724
445	# request one	725	When the first callback is called and sees an "OK" response, it will
		726	C<unshift> another line-read. This line-read will be queued I<before> the
		727	64-byte chunk callback.
		728
		729	# request one, returns either "OK + extra line" or "ERROR"
446	$handle->push_write ("request 1\015\012");	730	$handle->push_write ("request 1\015\012");
447		731
448	# we expect "ERROR" or "OK" as response, so push a line read	732	# we expect "ERROR" or "OK" as response, so push a line read
449	$handle->push_read_line (sub {	733	$handle->push_read (line => sub {
450	# if we got an "OK", we have to _prepend_ another line,	734	# if we got an "OK", we have to _prepend_ another line,
451	# so it will be read before the second request reads its 64 bytes	735	# so it will be read before the second request reads its 64 bytes
452	# which are already in the queue when this callback is called	736	# which are already in the queue when this callback is called
453	# we don't do this in case we got an error	737	# we don't do this in case we got an error
454	if ($_[1] eq "OK") {	738	if ($_[1] eq "OK") {
455	$_[0]->unshift_read_line (sub {	739	$_[0]->unshift_read (line => sub {
456	my $response = $_[1];	740	my $response = $_[1];
457	...	741	...
458	});	742	});
459	}	743	}
460	});	744	});
461		745
462	# request two	746	# request two, simply returns 64 octets
463	$handle->push_write ("request 2\015\012");	747	$handle->push_write ("request 2\015\012");
464		748
465	# simply read 64 bytes, always	749	# simply read 64 bytes, always
466	$handle->push_read_chunk (64, sub {	750	$handle->push_read (chunk => 64, sub {
467	my $response = $_[1];	751	my $response = $_[1];
468	...	752	...
469	});	753	});
470		754
471	=over 4	755	=over 4
472		756
473	=cut	757	=cut
474		758
475	sub _drain_rbuf {	759	sub _drain_rbuf {
476	my ($self) = @_;	760	my ($self) = @_;
		761
		762	local $self->{_in_drain} = 1;
477		763
478	if (	764	if (
479	defined $self->{rbuf_max}	765	defined $self->{rbuf_max}
480	&& $self->{rbuf_max} < length $self->{rbuf}	766	&& $self->{rbuf_max} < length $self->{rbuf}
481	) {	767	) {
482	$! = &Errno::ENOSPC;	768	$self->_error (&Errno::ENOSPC, 1), return;
483	$self->error;
484	}	769	}
485		770
486	return if $self->{in_drain};	771	while () {
487	local $self->{in_drain} = 1;
488
489	while (my $len = length $self->{rbuf}) {	772	my $len = length $self->{rbuf};
490	no strict 'refs';	773
491	if (my $cb = shift @{ $self->{_queue} }) {	774	if (my $cb = shift @{ $self->{_queue} }) {
492	unless ($cb->($self)) {	775	unless ($cb->($self)) {
493	if ($self->{_eof}) {	776	if ($self->{_eof}) {
494	# no progress can be made (not enough data and no data forthcoming)	777	# no progress can be made (not enough data and no data forthcoming)
495	$! = &Errno::EPIPE;	778	$self->_error (&Errno::EPIPE, 1), return;
496	$self->error;
497	}	779	}
498		780
499	unshift @{ $self->{_queue} }, $cb;	781	unshift @{ $self->{_queue} }, $cb;
500	return;	782	last;
501	}	783	}
502	} elsif ($self->{on_read}) {	784	} elsif ($self->{on_read}) {
		785	last unless $len;
		786
503	$self->{on_read}($self);	787	$self->{on_read}($self);
504		788
505	if (	789	if (
506	$self->{_eof} # if no further data will arrive
507	&& $len == length $self->{rbuf} # and no data has been consumed	790	$len == length $self->{rbuf} # if no data has been consumed
508	&& !@{ $self->{_queue} } # and the queue is still empty	791	&& !@{ $self->{_queue} } # and the queue is still empty
509	&& $self->{on_read} # and we still want to read data	792	&& $self->{on_read} # but we still have on_read
510	) {	793	) {
		794	# no further data will arrive
511	# then no progress can be made	795	# so no progress can be made
512	$! = &Errno::EPIPE;	796	$self->_error (&Errno::EPIPE, 1), return
513	$self->error;	797	if $self->{_eof};
		798
		799	last; # more data might arrive
514	}	800	}
515	} else {	801	} else {
516	# read side becomes idle	802	# read side becomes idle
517	delete $self->{_rw};	803	delete $self->{_rw} unless $self->{tls};
518	return;	804	last;
519	}	805	}
520	}	806	}
521		807
522	if ($self->{_eof}) {	808	if ($self->{_eof}) {
523	$self->_shutdown;	809	if ($self->{on_eof}) {
524	$self->{on_eof}($self)	810	$self->{on_eof}($self)
525	if $self->{on_eof};	811	} else {
		812	$self->_error (0, 1);
		813	}
		814	}
		815
		816	# may need to restart read watcher
		817	unless ($self->{_rw}) {
		818	$self->start_read
		819	if $self->{on_read} || @{ $self->{_queue} };
526	}	820	}
527	}	821	}
528		822
529	=item $handle->on_read ($cb)	823	=item $handle->on_read ($cb)
530		824
…		…
536		830
537	sub on_read {	831	sub on_read {
538	my ($self, $cb) = @_;	832	my ($self, $cb) = @_;
539		833
540	$self->{on_read} = $cb;	834	$self->{on_read} = $cb;
		835	$self->_drain_rbuf if $cb && !$self->{_in_drain};
541	}	836	}
542		837
543	=item $handle->rbuf	838	=item $handle->rbuf
544		839
545	Returns the read buffer (as a modifiable lvalue).	840	Returns the read buffer (as a modifiable lvalue).
…		…
594	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	889	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
595	->($self, $cb, @_);	890	->($self, $cb, @_);
596	}	891	}
597		892
598	push @{ $self->{_queue} }, $cb;	893	push @{ $self->{_queue} }, $cb;
599	$self->_drain_rbuf;	894	$self->_drain_rbuf unless $self->{_in_drain};
600	}	895	}
601		896
602	sub unshift_read {	897	sub unshift_read {
603	my $self = shift;	898	my $self = shift;
604	my $cb = pop;	899	my $cb = pop;
…		…
610	->($self, $cb, @_);	905	->($self, $cb, @_);
611	}	906	}
612		907
613		908
614	unshift @{ $self->{_queue} }, $cb;	909	unshift @{ $self->{_queue} }, $cb;
615	$self->_drain_rbuf;	910	$self->_drain_rbuf unless $self->{_in_drain};
616	}	911	}
617		912
618	=item $handle->push_read (type => @args, $cb)	913	=item $handle->push_read (type => @args, $cb)
619		914
620	=item $handle->unshift_read (type => @args, $cb)	915	=item $handle->unshift_read (type => @args, $cb)
…		…
626	Predefined types are (if you have ideas for additional types, feel free to	921	Predefined types are (if you have ideas for additional types, feel free to
627	drop by and tell us):	922	drop by and tell us):
628		923
629	=over 4	924	=over 4
630		925
631	=item chunk => $octets, $cb->($self, $data)	926	=item chunk => $octets, $cb->($handle, $data)
632		927
633	Invoke the callback only once C<$octets> bytes have been read. Pass the	928	Invoke the callback only once C<$octets> bytes have been read. Pass the
634	data read to the callback. The callback will never be called with less	929	data read to the callback. The callback will never be called with less
635	data.	930	data.
636		931
…		…
650	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	945	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
651	1	946	1
652	}	947	}
653	};	948	};
654		949
655	# compatibility with older API
656	sub push_read_chunk {
657	$_[0]->push_read (chunk => $_[1], $_[2]);
658	}
659
660	sub unshift_read_chunk {
661	$_[0]->unshift_read (chunk => $_[1], $_[2]);
662	}
663
664	=item line => [$eol, ]$cb->($self, $line, $eol)	950	=item line => [$eol, ]$cb->($handle, $line, $eol)
665		951
666	The callback will be called only once a full line (including the end of	952	The callback will be called only once a full line (including the end of
667	line marker, C<$eol>) has been read. This line (excluding the end of line	953	line marker, C<$eol>) has been read. This line (excluding the end of line
668	marker) will be passed to the callback as second argument (C<$line>), and	954	marker) will be passed to the callback as second argument (C<$line>), and
669	the end of line marker as the third argument (C<$eol>).	955	the end of line marker as the third argument (C<$eol>).
…		…
683	=cut	969	=cut
684		970
685	register_read_type line => sub {	971	register_read_type line => sub {
686	my ($self, $cb, $eol) = @_;	972	my ($self, $cb, $eol) = @_;
687		973
688	$eol = qr|(\015?\012)| if @_ < 3;	974	if (@_ < 3) {
		975	# this is more than twice as fast as the generic code below
		976	sub {
		977	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		978
		979	$cb->($_[0], $1, $2);
		980	1
		981	}
		982	} else {
689	$eol = quotemeta $eol unless ref $eol;	983	$eol = quotemeta $eol unless ref $eol;
690	$eol = qr|^(.*?)($eol)|s;	984	$eol = qr|^(.*?)($eol)|s;
691		985
692	sub {	986	sub {
693	$_[0]{rbuf} =~ s/$eol// or return;	987	$_[0]{rbuf} =~ s/$eol// or return;
694		988
695	$cb->($_[0], $1, $2);	989	$cb->($_[0], $1, $2);
		990	1
696	1	991	}
697	}	992	}
698	};	993	};
699		994
700	# compatibility with older API
701	sub push_read_line {
702	my $self = shift;
703	$self->push_read (line => @_);
704	}
705
706	sub unshift_read_line {
707	my $self = shift;
708	$self->unshift_read (line => @_);
709	}
710
711	=item netstring => $cb->($string)
712
713	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
714
715	Throws an error with C<$!> set to EBADMSG on format violations.
716
717	=cut
718
719	register_read_type netstring => sub {
720	my ($self, $cb) = @_;
721
722	sub {
723	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
724	if ($_[0]{rbuf} =~ /[^0-9]/) {
725	$! = &Errno::EBADMSG;
726	$self->error;
727	}
728	return;
729	}
730
731	my $len = $1;
732
733	$self->unshift_read (chunk => $len, sub {
734	my $string = $_[1];
735	$_[0]->unshift_read (chunk => 1, sub {
736	if ($_[1] eq ",") {
737	$cb->($_[0], $string);
738	} else {
739	$! = &Errno::EBADMSG;
740	$self->error;
741	}
742	});
743	});
744
745	1
746	}
747	};
748
749	=item regex => $accept[, $reject[, $skip], $cb->($data)	995	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
750		996
751	Makes a regex match against the regex object C<$accept> and returns	997	Makes a regex match against the regex object C<$accept> and returns
752	everything up to and including the match.	998	everything up to and including the match.
753		999
754	Example: read a single line terminated by '\n'.	1000	Example: read a single line terminated by '\n'.
…		…
802	return 1;	1048	return 1;
803	}	1049	}
804		1050
805	# reject	1051	# reject
806	if ($reject && $$rbuf =~ $reject) {	1052	if ($reject && $$rbuf =~ $reject) {
807	$! = &Errno::EBADMSG;	1053	$self->_error (&Errno::EBADMSG);
808	$self->error;
809	}	1054	}
810		1055
811	# skip	1056	# skip
812	if ($skip && $$rbuf =~ $skip) {	1057	if ($skip && $$rbuf =~ $skip) {
813	$data .= substr $$rbuf, 0, $+[0], "";	1058	$data .= substr $$rbuf, 0, $+[0], "";
…		…
815		1060
816	()	1061	()
817	}	1062	}
818	};	1063	};
819		1064
		1065	=item netstring => $cb->($handle, $string)
		1066
		1067	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1068
		1069	Throws an error with C<$!> set to EBADMSG on format violations.
		1070
		1071	=cut
		1072
		1073	register_read_type netstring => sub {
		1074	my ($self, $cb) = @_;
		1075
		1076	sub {
		1077	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1078	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1079	$self->_error (&Errno::EBADMSG);
		1080	}
		1081	return;
		1082	}
		1083
		1084	my $len = $1;
		1085
		1086	$self->unshift_read (chunk => $len, sub {
		1087	my $string = $_[1];
		1088	$_[0]->unshift_read (chunk => 1, sub {
		1089	if ($_[1] eq ",") {
		1090	$cb->($_[0], $string);
		1091	} else {
		1092	$self->_error (&Errno::EBADMSG);
		1093	}
		1094	});
		1095	});
		1096
		1097	1
		1098	}
		1099	};
		1100
		1101	=item packstring => $format, $cb->($handle, $string)
		1102
		1103	An octet string prefixed with an encoded length. The encoding C<$format>
		1104	uses the same format as a Perl C<pack> format, but must specify a single
		1105	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1106	optional C<!>, C<< < >> or C<< > >> modifier).
		1107
		1108	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1109	EPP uses a prefix of C<N> (4 octtes).
		1110
		1111	Example: read a block of data prefixed by its length in BER-encoded
		1112	format (very efficient).
		1113
		1114	$handle->push_read (packstring => "w", sub {
		1115	my ($handle, $data) = @_;
		1116	});
		1117
		1118	=cut
		1119
		1120	register_read_type packstring => sub {
		1121	my ($self, $cb, $format) = @_;
		1122
		1123	sub {
		1124	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1125	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1126	or return;
		1127
		1128	$format = length pack $format, $len;
		1129
		1130	# bypass unshift if we already have the remaining chunk
		1131	if ($format + $len <= length $_[0]{rbuf}) {
		1132	my $data = substr $_[0]{rbuf}, $format, $len;
		1133	substr $_[0]{rbuf}, 0, $format + $len, "";
		1134	$cb->($_[0], $data);
		1135	} else {
		1136	# remove prefix
		1137	substr $_[0]{rbuf}, 0, $format, "";
		1138
		1139	# read remaining chunk
		1140	$_[0]->unshift_read (chunk => $len, $cb);
		1141	}
		1142
		1143	1
		1144	}
		1145	};
		1146
		1147	=item json => $cb->($handle, $hash_or_arrayref)
		1148
		1149	Reads a JSON object or array, decodes it and passes it to the callback.
		1150
		1151	If a C<json> object was passed to the constructor, then that will be used
		1152	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1153
		1154	This read type uses the incremental parser available with JSON version
		1155	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1156	dependency on your own: this module will load the JSON module, but
		1157	AnyEvent does not depend on it itself.
		1158
		1159	Since JSON texts are fully self-delimiting, the C<json> read and write
		1160	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1161	the C<json> write type description, above, for an actual example.
		1162
		1163	=cut
		1164
		1165	register_read_type json => sub {
		1166	my ($self, $cb) = @_;
		1167
		1168	require JSON;
		1169
		1170	my $data;
		1171	my $rbuf = \$self->{rbuf};
		1172
		1173	my $json = $self->{json} ||= JSON->new->utf8;
		1174
		1175	sub {
		1176	my $ref = $json->incr_parse ($self->{rbuf});
		1177
		1178	if ($ref) {
		1179	$self->{rbuf} = $json->incr_text;
		1180	$json->incr_text = "";
		1181	$cb->($self, $ref);
		1182
		1183	1
		1184	} else {
		1185	$self->{rbuf} = "";
		1186	()
		1187	}
		1188	}
		1189	};
		1190
		1191	=item storable => $cb->($handle, $ref)
		1192
		1193	Deserialises a L<Storable> frozen representation as written by the
		1194	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1195	data).
		1196
		1197	Raises C<EBADMSG> error if the data could not be decoded.
		1198
		1199	=cut
		1200
		1201	register_read_type storable => sub {
		1202	my ($self, $cb) = @_;
		1203
		1204	require Storable;
		1205
		1206	sub {
		1207	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1208	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1209	or return;
		1210
		1211	my $format = length pack "w", $len;
		1212
		1213	# bypass unshift if we already have the remaining chunk
		1214	if ($format + $len <= length $_[0]{rbuf}) {
		1215	my $data = substr $_[0]{rbuf}, $format, $len;
		1216	substr $_[0]{rbuf}, 0, $format + $len, "";
		1217	$cb->($_[0], Storable::thaw ($data));
		1218	} else {
		1219	# remove prefix
		1220	substr $_[0]{rbuf}, 0, $format, "";
		1221
		1222	# read remaining chunk
		1223	$_[0]->unshift_read (chunk => $len, sub {
		1224	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1225	$cb->($_[0], $ref);
		1226	} else {
		1227	$self->_error (&Errno::EBADMSG);
		1228	}
		1229	});
		1230	}
		1231
		1232	1
		1233	}
		1234	};
		1235
820	=back	1236	=back
821		1237
822	=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args)	1238	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
823		1239
824	This function (not method) lets you add your own types to C<push_read>.	1240	This function (not method) lets you add your own types to C<push_read>.
825		1241
826	Whenever the given C<type> is used, C<push_read> will invoke the code	1242	Whenever the given C<type> is used, C<push_read> will invoke the code
827	reference with the handle object, the callback and the remaining	1243	reference with the handle object, the callback and the remaining
…		…
829		1245
830	The code reference is supposed to return a callback (usually a closure)	1246	The code reference is supposed to return a callback (usually a closure)
831	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1247	that works as a plain read callback (see C<< ->push_read ($cb) >>).
832		1248
833	It should invoke the passed callback when it is done reading (remember to	1249	It should invoke the passed callback when it is done reading (remember to
834	pass C<$self> as first argument as all other callbacks do that).	1250	pass C<$handle> as first argument as all other callbacks do that).
835		1251
836	Note that this is a function, and all types registered this way will be	1252	Note that this is a function, and all types registered this way will be
837	global, so try to use unique names.	1253	global, so try to use unique names.
838		1254
839	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1255	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
…		…
842	=item $handle->stop_read	1258	=item $handle->stop_read
843		1259
844	=item $handle->start_read	1260	=item $handle->start_read
845		1261
846	In rare cases you actually do not want to read anything from the	1262	In rare cases you actually do not want to read anything from the
847	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1263	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
848	any queued callbacks will be executed then. To start reading again, call	1264	any queued callbacks will be executed then. To start reading again, call
849	C<start_read>.	1265	C<start_read>.
850		1266
		1267	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1268	you change the C<on_read> callback or push/unshift a read callback, and it
		1269	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1270	there are any read requests in the queue.
		1271
		1272	These methods will have no effect when in TLS mode (as TLS doesn't support
		1273	half-duplex connections).
		1274
851	=cut	1275	=cut
852		1276
853	sub stop_read {	1277	sub stop_read {
854	my ($self) = @_;	1278	my ($self) = @_;
855		1279
856	delete $self->{_rw};	1280	delete $self->{_rw} unless $self->{tls};
857	}	1281	}
858		1282
859	sub start_read {	1283	sub start_read {
860	my ($self) = @_;	1284	my ($self) = @_;
861		1285
862	unless ($self->{_rw} || $self->{_eof}) {	1286	unless ($self->{_rw} || $self->{_eof}) {
863	Scalar::Util::weaken $self;	1287	Scalar::Util::weaken $self;
864		1288
865	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1289	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
866	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1290	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
867	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1291	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
868		1292
869	if ($len > 0) {	1293	if ($len > 0) {
870	$self->{filter_r}	1294	$self->{_activity} = AnyEvent->now;
871	? $self->{filter_r}->($self, $rbuf)	1295
872	: $self->_drain_rbuf;	1296	if ($self->{tls}) {
		1297	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1298
		1299	&_dotls ($self);
		1300	} else {
		1301	$self->_drain_rbuf unless $self->{_in_drain};
		1302	}
873		1303
874	} elsif (defined $len) {	1304	} elsif (defined $len) {
875	delete $self->{_rw};	1305	delete $self->{_rw};
876	$self->{_eof} = 1;	1306	$self->{_eof} = 1;
877	$self->_drain_rbuf;	1307	$self->_drain_rbuf unless $self->{_in_drain};
878		1308
879	} elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) {	1309	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
880	return $self->error;	1310	return $self->_error ($!, 1);
881	}	1311	}
882	});	1312	});
883	}	1313	}
884	}	1314	}
885		1315
		1316	# poll the write BIO and send the data if applicable
886	sub _dotls {	1317	sub _dotls {
887	my ($self) = @_;	1318	my ($self) = @_;
888		1319
		1320	my $tmp;
		1321
889	if (length $self->{_tls_wbuf}) {	1322	if (length $self->{_tls_wbuf}) {
890	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1323	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
891	substr $self->{_tls_wbuf}, 0, $len, "";	1324	substr $self->{_tls_wbuf}, 0, $tmp, "";
892	}	1325	}
893	}	1326	}
894		1327
		1328	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1329	unless (length $tmp) {
		1330	# let's treat SSL-eof as we treat normal EOF
		1331	delete $self->{_rw};
		1332	$self->{_eof} = 1;
		1333	&_freetls;
		1334	}
		1335
		1336	$self->{rbuf} .= $tmp;
		1337	$self->_drain_rbuf unless $self->{_in_drain};
		1338	$self->{tls} or return; # tls session might have gone away in callback
		1339	}
		1340
		1341	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1342
		1343	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
		1344	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
		1345	return $self->_error ($!, 1);
		1346	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
		1347	return $self->_error (&Errno::EIO, 1);
		1348	}
		1349
		1350	# all other errors are fine for our purposes
		1351	}
		1352
895	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1353	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
896	$self->{wbuf} .= $buf;	1354	$self->{wbuf} .= $tmp;
897	$self->_drain_wbuf;	1355	$self->_drain_wbuf;
898	}
899
900	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
901	$self->{rbuf} .= $buf;
902	$self->_drain_rbuf;
903	}
904
905	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
906
907	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
908	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
909	$self->error;
910	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
911	$! = &Errno::EIO;
912	$self->error;
913	}
914
915	# all others are fine for our purposes
916	}	1356	}
917	}	1357	}
918		1358
919	=item $handle->starttls ($tls[, $tls_ctx])	1359	=item $handle->starttls ($tls[, $tls_ctx])
920		1360
…		…
930		1370
931	The TLS connection object will end up in C<< $handle->{tls} >> after this	1371	The TLS connection object will end up in C<< $handle->{tls} >> after this
932	call and can be used or changed to your liking. Note that the handshake	1372	call and can be used or changed to your liking. Note that the handshake
933	might have already started when this function returns.	1373	might have already started when this function returns.
934		1374
935	=cut	1375	If it an error to start a TLS handshake more than once per
		1376	AnyEvent::Handle object (this is due to bugs in OpenSSL).
936		1377
937	# TODO: maybe document...	1378	=cut
		1379
938	sub starttls {	1380	sub starttls {
939	my ($self, $ssl, $ctx) = @_;	1381	my ($self, $ssl, $ctx) = @_;
940		1382
941	$self->stoptls;	1383	require Net::SSLeay;
942		1384
		1385	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1386	if $self->{tls};
		1387
943	if ($ssl eq "accept") {	1388	if ($ssl eq "accept") {
944	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1389	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
945	Net::SSLeay::set_accept_state ($ssl);	1390	Net::SSLeay::set_accept_state ($ssl);
946	} elsif ($ssl eq "connect") {	1391	} elsif ($ssl eq "connect") {
947	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1392	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
…		…
953	# basically, this is deep magic (because SSL_read should have the same issues)	1398	# basically, this is deep magic (because SSL_read should have the same issues)
954	# but the openssl maintainers basically said: "trust us, it just works".	1399	# but the openssl maintainers basically said: "trust us, it just works".
955	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1400	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
956	# and mismaintained ssleay-module doesn't even offer them).	1401	# and mismaintained ssleay-module doesn't even offer them).
957	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1402	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1403	#
		1404	# in short: this is a mess.
		1405	#
		1406	# note that we do not try to keep the length constant between writes as we are required to do.
		1407	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1408	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1409	# have identity issues in that area.
958	Net::SSLeay::CTX_set_mode ($self->{tls},	1410	Net::SSLeay::CTX_set_mode ($self->{tls},
959	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1411	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
960	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1412	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
961		1413
962	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1414	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
963	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1415	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
964		1416
965	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1417	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
966		1418
967	$self->{filter_w} = sub {	1419	&_dotls; # need to trigger the initial handshake
968	$_[0]{_tls_wbuf} .= ${$_[1]};	1420	$self->start_read; # make sure we actually do read
969	&_dotls;
970	};
971	$self->{filter_r} = sub {
972	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
973	&_dotls;
974	};
975	}	1421	}
976		1422
977	=item $handle->stoptls	1423	=item $handle->stoptls
978		1424
979	Destroys the SSL connection, if any. Partial read or write data will be	1425	Shuts down the SSL connection - this makes a proper EOF handshake by
980	lost.	1426	sending a close notify to the other side, but since OpenSSL doesn't
		1427	support non-blocking shut downs, it is not possible to re-use the stream
		1428	afterwards.
981		1429
982	=cut	1430	=cut
983		1431
984	sub stoptls {	1432	sub stoptls {
985	my ($self) = @_;	1433	my ($self) = @_;
986		1434
		1435	if ($self->{tls}) {
		1436	Net::SSLeay::shutdown ($self->{tls});
		1437
		1438	&_dotls;
		1439
		1440	# we don't give a shit. no, we do, but we can't. no...
		1441	# we, we... have to use openssl :/
		1442	&_freetls;
		1443	}
		1444	}
		1445
		1446	sub _freetls {
		1447	my ($self) = @_;
		1448
		1449	return unless $self->{tls};
		1450
987	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1451	Net::SSLeay::free (delete $self->{tls});
988		1452
989	delete $self->{_rbio};	1453	delete @$self{qw(_rbio _wbio _tls_wbuf)};
990	delete $self->{_wbio};
991	delete $self->{_tls_wbuf};
992	delete $self->{filter_r};
993	delete $self->{filter_w};
994	}	1454	}
995		1455
996	sub DESTROY {	1456	sub DESTROY {
997	my $self = shift;	1457	my $self = shift;
998		1458
999	$self->stoptls;	1459	&_freetls;
		1460
		1461	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1462
		1463	if ($linger && length $self->{wbuf}) {
		1464	my $fh = delete $self->{fh};
		1465	my $wbuf = delete $self->{wbuf};
		1466
		1467	my @linger;
		1468
		1469	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1470	my $len = syswrite $fh, $wbuf, length $wbuf;
		1471
		1472	if ($len > 0) {
		1473	substr $wbuf, 0, $len, "";
		1474	} else {
		1475	@linger = (); # end
		1476	}
		1477	});
		1478	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1479	@linger = ();
		1480	});
		1481	}
		1482	}
		1483
		1484	=item $handle->destroy
		1485
		1486	Shuts down the handle object as much as possible - this call ensures that
		1487	no further callbacks will be invoked and resources will be freed as much
		1488	as possible. You must not call any methods on the object afterwards.
		1489
		1490	Normally, you can just "forget" any references to an AnyEvent::Handle
		1491	object and it will simply shut down. This works in fatal error and EOF
		1492	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1493	callback, so when you want to destroy the AnyEvent::Handle object from
		1494	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1495	that case.
		1496
		1497	The handle might still linger in the background and write out remaining
		1498	data, as specified by the C<linger> option, however.
		1499
		1500	=cut
		1501
		1502	sub destroy {
		1503	my ($self) = @_;
		1504
		1505	$self->DESTROY;
		1506	%$self = ();
1000	}	1507	}
1001		1508
1002	=item AnyEvent::Handle::TLS_CTX	1509	=item AnyEvent::Handle::TLS_CTX
1003		1510
1004	This function creates and returns the Net::SSLeay::CTX object used by	1511	This function creates and returns the Net::SSLeay::CTX object used by
…		…
1034	}	1541	}
1035	}	1542	}
1036		1543
1037	=back	1544	=back
1038		1545
		1546
		1547	=head1 NONFREQUENTLY ASKED QUESTIONS
		1548
		1549	=over 4
		1550
		1551	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1552	still get further invocations!
		1553
		1554	That's because AnyEvent::Handle keeps a reference to itself when handling
		1555	read or write callbacks.
		1556
		1557	It is only safe to "forget" the reference inside EOF or error callbacks,
		1558	from within all other callbacks, you need to explicitly call the C<<
		1559	->destroy >> method.
		1560
		1561	=item I get different callback invocations in TLS mode/Why can't I pause
		1562	reading?
		1563
		1564	Unlike, say, TCP, TLS connections do not consist of two independent
		1565	communication channels, one for each direction. Or put differently. The
		1566	read and write directions are not independent of each other: you cannot
		1567	write data unless you are also prepared to read, and vice versa.
		1568
		1569	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1570	callback invocations when you are not expecting any read data - the reason
		1571	is that AnyEvent::Handle always reads in TLS mode.
		1572
		1573	During the connection, you have to make sure that you always have a
		1574	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1575	connection (or when you no longer want to use it) you can call the
		1576	C<destroy> method.
		1577
		1578	=item How do I read data until the other side closes the connection?
		1579
		1580	If you just want to read your data into a perl scalar, the easiest way
		1581	to achieve this is by setting an C<on_read> callback that does nothing,
		1582	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1583	will be in C<$_[0]{rbuf}>:
		1584
		1585	$handle->on_read (sub { });
		1586	$handle->on_eof (undef);
		1587	$handle->on_error (sub {
		1588	my $data = delete $_[0]{rbuf};
		1589	undef $handle;
		1590	});
		1591
		1592	The reason to use C<on_error> is that TCP connections, due to latencies
		1593	and packets loss, might get closed quite violently with an error, when in
		1594	fact, all data has been received.
		1595
		1596	It is usually better to use acknowledgements when transferring data,
		1597	to make sure the other side hasn't just died and you got the data
		1598	intact. This is also one reason why so many internet protocols have an
		1599	explicit QUIT command.
		1600
		1601	=item I don't want to destroy the handle too early - how do I wait until
		1602	all data has been written?
		1603
		1604	After writing your last bits of data, set the C<on_drain> callback
		1605	and destroy the handle in there - with the default setting of
		1606	C<low_water_mark> this will be called precisely when all data has been
		1607	written to the socket:
		1608
		1609	$handle->push_write (...);
		1610	$handle->on_drain (sub {
		1611	warn "all data submitted to the kernel\n";
		1612	undef $handle;
		1613	});
		1614
		1615	=back
		1616
		1617
1039	=head1 SUBCLASSING AnyEvent::Handle	1618	=head1 SUBCLASSING AnyEvent::Handle
1040		1619
1041	In many cases, you might want to subclass AnyEvent::Handle.	1620	In many cases, you might want to subclass AnyEvent::Handle.
1042		1621
1043	To make this easier, a given version of AnyEvent::Handle uses these	1622	To make this easier, a given version of AnyEvent::Handle uses these
…		…
1046	=over 4	1625	=over 4
1047		1626
1048	=item * all constructor arguments become object members.	1627	=item * all constructor arguments become object members.
1049		1628
1050	At least initially, when you pass a C<tls>-argument to the constructor it	1629	At least initially, when you pass a C<tls>-argument to the constructor it
1051	will end up in C<< $handle->{tls} >>. Those members might be changes or	1630	will end up in C<< $handle->{tls} >>. Those members might be changed or
1052	mutated later on (for example C<tls> will hold the TLS connection object).	1631	mutated later on (for example C<tls> will hold the TLS connection object).
1053		1632
1054	=item * other object member names are prefixed with an C<_>.	1633	=item * other object member names are prefixed with an C<_>.
1055		1634
1056	All object members not explicitly documented (internal use) are prefixed	1635	All object members not explicitly documented (internal use) are prefixed

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