ViewVC Help

View File | Revision Log | Show Annotations | Download File

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

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.27 by root, Sat May 24 15:26:04 2008 UTC vs.
Revision 1.113 by root, Wed Jan 21 06:02:21 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 ();	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	This module is experimental.
18
19	=cut	17	=cut
20		18
21	our $VERSION = '0.04';	19	our $VERSION = 4.331;
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->send;
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
…		…
69		73
70	=item fh => $filehandle [MANDATORY]	74	=item fh => $filehandle [MANDATORY]
71		75
72	The filehandle this L<AnyEvent::Handle> object will operate on.	76	The filehandle this L<AnyEvent::Handle> object will operate on.
73		77
74	NOTE: The filehandle will be set to non-blocking (using	78	NOTE: The filehandle will be set to non-blocking mode (using
75	AnyEvent::Util::fh_nonblocking).	79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
76		81
77	=item on_eof => $cb->($self)	82	=item on_eof => $cb->($handle)
78		83
79	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.
80		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
81	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,
82	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
83	waiting for data.	95	waiting for data.
84		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
85	=item on_error => $cb->($self)	100	=item on_error => $cb->($handle, $fatal)
86		101
87	This is the fatal error callback, that is called when, well, a fatal error	102	This is the error callback, which is called when, well, some error
88	occurs, such as not being able to resolve the hostname, failure to connect	103	occured, such as not being able to resolve the hostname, failure to
89	or a read error.	104	connect or a read error.
90		105
91	The object will not be in a usable state when this callback has been	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
92	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>).
93		116
94	On callback entrance, the value of C<$!> contains the operating system	117	On callback entrance, the value of C<$!> contains the operating system
95	error (or C<ENOSPC> or C<EPIPE>).	118	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
96		119
97	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
98	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
99	die.	122	C<croak>.
100		123
101	=item on_read => $cb->($self)	124	=item on_read => $cb->($handle)
102		125
103	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
104	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).
105		130
106	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 >>
107	method or access the C<$self->{rbuf}> member directly.	132	method or access the C<$handle->{rbuf}> member directly.
108		133
109	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
110	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
111	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
112	error will be raised (with C<$!> set to C<EPIPE>).	137	error will be raised (with C<$!> set to C<EPIPE>).
113		138
114	=item on_drain => $cb->()	139	=item on_drain => $cb->($handle)
115		140
116	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
117	(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).
118		143
119	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.
120		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
121	=item rbuf_max => <bytes>	173	=item rbuf_max => <bytes>
122		174
123	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>)
124	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
125	avoid denial-of-service attacks.	177	avoid some forms of denial-of-service attacks.
126		178
127	For example, a server accepting connections from untrusted sources should	179	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	180	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	181	(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	182	amount of data without a callback ever being called as long as the line
131	isn't finished).	183	isn't finished).
132		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
133	=item read_size => <bytes>	211	=item read_size => <bytes>
134		212
135	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
136	on each [loop iteration). Default: C<4096>.	214	try to read during each loop iteration, which affects memory
		215	requirements). Default: C<8192>.
137		216
138	=item low_water_mark => <bytes>	217	=item low_water_mark => <bytes>
139		218
140	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
141	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
142	considered empty.	221	considered empty.
143		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
144	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	240	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
145		241
146	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
147	will start making tls handshake and will transparently encrypt/decrypt	243	AnyEvent will start a TLS handshake as soon as the conenction has been
148	data.	244	established and will transparently encrypt/decrypt data afterwards.
149		245
150	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
151	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.
152		250
153	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
154	connection, use C<connect> mode.	252	C<accept>, and for the TLS client side of a connection, use C<connect>
		253	mode.
155		254
156	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
157	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>
158	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
159	AnyEvent::Handle.	258	AnyEvent::Handle.
160		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
161	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.
162		266
163	=item tls_ctx => $ssl_ctx	267	=item tls_ctx => $ssl_ctx
164		268
165	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
166	(unless a connection object was specified directly). If this parameter is	270	(unless a connection object was specified directly). If this parameter is
167	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	271	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
168		272
		273	=item json => JSON or JSON::XS object
		274
		275	This is the json coder object used by the C<json> read and write types.
		276
		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.
		283
169	=back	284	=back
170		285
171	=cut	286	=cut
172		287
173	sub new {	288	sub new {
…		…
177		292
178	$self->{fh} or Carp::croak "mandatory argument fh is missing";	293	$self->{fh} or Carp::croak "mandatory argument fh is missing";
179		294
180	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	295	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
181		296
182	if ($self->{tls}) {
183	require Net::SSLeay;
184	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	297	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
185	}	298	if $self->{tls};
186		299
187	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};	300	$self->{_activity} = AnyEvent->now;
188	$self->on_error (delete $self->{on_error}) if $self->{on_error};	301	$self->_timeout;
		302
189	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	303	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
190	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	304	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
191		305
192	$self->start_read;	306	$self->start_read
		307	if $self->{on_read};
193		308
194	$self	309	$self
195	}	310	}
196		311
197	sub _shutdown {	312	sub _shutdown {
198	my ($self) = @_;	313	my ($self) = @_;
199		314
		315	delete $self->{_tw};
200	delete $self->{rw};	316	delete $self->{_rw};
201	delete $self->{ww};	317	delete $self->{_ww};
202	delete $self->{fh};	318	delete $self->{fh};
203	}
204		319
		320	&_freetls;
		321
		322	delete $self->{on_read};
		323	delete $self->{_queue};
		324	}
		325
205	sub error {	326	sub _error {
206	my ($self) = @_;	327	my ($self, $errno, $fatal) = @_;
207		328
208	{
209	local $!;
210	$self->_shutdown;	329	$self->_shutdown
211	}	330	if $fatal;
		331
		332	$! = $errno;
212		333
213	if ($self->{on_error}) {	334	if ($self->{on_error}) {
214	$self->{on_error}($self);	335	$self->{on_error}($self, $fatal);
215	} else {	336	} elsif ($self->{fh}) {
216	die "AnyEvent::Handle uncaught fatal error: $!";	337	Carp::croak "AnyEvent::Handle uncaught error: $!";
217	}	338	}
218	}	339	}
219		340
220	=item $fh = $handle->fh	341	=item $fh = $handle->fh
221		342
222	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.
223		344
224	=cut	345	=cut
225		346
226	sub fh { $_[0]->{fh} }	347	sub fh { $_[0]{fh} }
227		348
228	=item $handle->on_error ($cb)	349	=item $handle->on_error ($cb)
229		350
230	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	351	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
231		352
…		…
243		364
244	sub on_eof {	365	sub on_eof {
245	$_[0]{on_eof} = $_[1];	366	$_[0]{on_eof} = $_[1];
246	}	367	}
247		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 $self->{_tw};
		460	}
		461	}
		462
248	#############################################################################	463	#############################################################################
249		464
250	=back	465	=back
251		466
252	=head2 WRITE QUEUE	467	=head2 WRITE QUEUE
…		…
273	my ($self, $cb) = @_;	488	my ($self, $cb) = @_;
274		489
275	$self->{on_drain} = $cb;	490	$self->{on_drain} = $cb;
276		491
277	$cb->($self)	492	$cb->($self)
278	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	493	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
279	}	494	}
280		495
281	=item $handle->push_write ($data)	496	=item $handle->push_write ($data)
282		497
283	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
…		…
287	=cut	502	=cut
288		503
289	sub _drain_wbuf {	504	sub _drain_wbuf {
290	my ($self) = @_;	505	my ($self) = @_;
291		506
292	unless ($self->{ww}) {	507	if (!$self->{_ww} && length $self->{wbuf}) {
		508
293	Scalar::Util::weaken $self;	509	Scalar::Util::weaken $self;
		510
294	my $cb = sub {	511	my $cb = sub {
295	my $len = syswrite $self->{fh}, $self->{wbuf};	512	my $len = syswrite $self->{fh}, $self->{wbuf};
296		513
297	if ($len > 0) {	514	if ($len >= 0) {
298	substr $self->{wbuf}, 0, $len, "";	515	substr $self->{wbuf}, 0, $len, "";
299		516
		517	$self->{_activity} = AnyEvent->now;
		518
300	$self->{on_drain}($self)	519	$self->{on_drain}($self)
301	if $self->{low_water_mark} >= length $self->{wbuf}	520	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
302	&& $self->{on_drain};	521	&& $self->{on_drain};
303		522
304	delete $self->{ww} unless length $self->{wbuf};	523	delete $self->{_ww} unless length $self->{wbuf};
305	} elsif ($! != EAGAIN && $! != EINTR) {	524	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
306	$self->error;	525	$self->_error ($!, 1);
307	}	526	}
308	};	527	};
309		528
		529	# try to write data immediately
		530	$cb->() unless $self->{autocork};
		531
		532	# if still data left in wbuf, we need to poll
310	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	533	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
311		534	if length $self->{wbuf};
312	$cb->($self);
313	};	535	};
		536	}
		537
		538	our %WH;
		539
		540	sub register_write_type($$) {
		541	$WH{$_[0]} = $_[1];
314	}	542	}
315		543
316	sub push_write {	544	sub push_write {
317	my $self = shift;	545	my $self = shift;
318		546
		547	if (@_ > 1) {
		548	my $type = shift;
		549
		550	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		551	->($self, @_);
		552	}
		553
319	if ($self->{filter_w}) {	554	if ($self->{tls}) {
320	$self->{filter_w}->($self, \$_[0]);	555	$self->{_tls_wbuf} .= $_[0];
		556
		557	&_dotls ($self);
321	} else {	558	} else {
322	$self->{wbuf} .= $_[0];	559	$self->{wbuf} .= $_[0];
323	$self->_drain_wbuf;	560	$self->_drain_wbuf;
324	}	561	}
325	}	562	}
326		563
		564	=item $handle->push_write (type => @args)
		565
		566	Instead of formatting your data yourself, you can also let this module do
		567	the job by specifying a type and type-specific arguments.
		568
		569	Predefined types are (if you have ideas for additional types, feel free to
		570	drop by and tell us):
		571
		572	=over 4
		573
		574	=item netstring => $string
		575
		576	Formats the given value as netstring
		577	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		578
		579	=cut
		580
		581	register_write_type netstring => sub {
		582	my ($self, $string) = @_;
		583
		584	(length $string) . ":$string,"
		585	};
		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
		660	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		661
		662	This function (not method) lets you add your own types to C<push_write>.
		663	Whenever the given C<type> is used, C<push_write> will invoke the code
		664	reference with the handle object and the remaining arguments.
		665
		666	The code reference is supposed to return a single octet string that will
		667	be appended to the write buffer.
		668
		669	Note that this is a function, and all types registered this way will be
		670	global, so try to use unique names.
		671
		672	=cut
		673
327	#############################################################################	674	#############################################################################
328		675
329	=back	676	=back
330		677
331	=head2 READ QUEUE	678	=head2 READ QUEUE
…		…
337	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
338	a queue.	685	a queue.
339		686
340	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
341	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
342	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
343	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).
344		692
345	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
346	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
347	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
348	below).	696	done its job (see C<push_read>, below).
349		697
350	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
351	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.
352		700
353	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
354	the specified number of bytes which give an XML datagram.	702	the specified number of bytes which give an XML datagram.
355		703
356	# in the default state, expect some header bytes	704	# in the default state, expect some header bytes
357	$handle->on_read (sub {	705	$handle->on_read (sub {
358	# 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)
359	shift->unshift_read_chunk (4, sub {	707	shift->unshift_read (chunk => 4, sub {
360	# header arrived, decode	708	# header arrived, decode
361	my $len = unpack "N", $_[1];	709	my $len = unpack "N", $_[1];
362		710
363	# now read the payload	711	# now read the payload
364	shift->unshift_read_chunk ($len, sub {	712	shift->unshift_read (chunk => $len, sub {
365	my $xml = $_[1];	713	my $xml = $_[1];
366	# handle xml	714	# handle xml
367	});	715	});
368	});	716	});
369	});	717	});
370		718
371	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"
372	"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
373	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
374	pipeline sending both requests and manipulate the queue as necessary in	722	just pipeline sending both requests and manipulate the queue as necessary
375	the callbacks:	723	in the callbacks.
376		724
377	# 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"
378	$handle->push_write ("request 1\015\012");	730	$handle->push_write ("request 1\015\012");
379		731
380	# 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
381	$handle->push_read_line (sub {	733	$handle->push_read (line => sub {
382	# if we got an "OK", we have to _prepend_ another line,	734	# if we got an "OK", we have to _prepend_ another line,
383	# 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
384	# which are already in the queue when this callback is called	736	# which are already in the queue when this callback is called
385	# we don't do this in case we got an error	737	# we don't do this in case we got an error
386	if ($_[1] eq "OK") {	738	if ($_[1] eq "OK") {
387	$_[0]->unshift_read_line (sub {	739	$_[0]->unshift_read (line => sub {
388	my $response = $_[1];	740	my $response = $_[1];
389	...	741	...
390	});	742	});
391	}	743	}
392	});	744	});
393		745
394	# request two	746	# request two, simply returns 64 octets
395	$handle->push_write ("request 2\015\012");	747	$handle->push_write ("request 2\015\012");
396		748
397	# simply read 64 bytes, always	749	# simply read 64 bytes, always
398	$handle->push_read_chunk (64, sub {	750	$handle->push_read (chunk => 64, sub {
399	my $response = $_[1];	751	my $response = $_[1];
400	...	752	...
401	});	753	});
402		754
403	=over 4	755	=over 4
404		756
405	=cut	757	=cut
406		758
407	sub _drain_rbuf {	759	sub _drain_rbuf {
408	my ($self) = @_;	760	my ($self) = @_;
		761
		762	local $self->{_in_drain} = 1;
409		763
410	if (	764	if (
411	defined $self->{rbuf_max}	765	defined $self->{rbuf_max}
412	&& $self->{rbuf_max} < length $self->{rbuf}	766	&& $self->{rbuf_max} < length $self->{rbuf}
413	) {	767	) {
414	$! = &Errno::ENOSPC; return $self->error;	768	$self->_error (&Errno::ENOSPC, 1), return;
415	}	769	}
416		770
417	return if $self->{in_drain};	771	while () {
418	local $self->{in_drain} = 1;
419
420	while (my $len = length $self->{rbuf}) {	772	my $len = length $self->{rbuf};
421	no strict 'refs';	773
422	if (my $cb = shift @{ $self->{queue} }) {	774	if (my $cb = shift @{ $self->{_queue} }) {
423	if (!$cb->($self)) {	775	unless ($cb->($self)) {
424	if ($self->{eof}) {	776	if ($self->{_eof}) {
425	# 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)
426	$! = &Errno::EPIPE; return $self->error;	778	$self->_error (&Errno::EPIPE, 1), return;
427	}	779	}
428		780
429	unshift @{ $self->{queue} }, $cb;	781	unshift @{ $self->{_queue} }, $cb;
430	return;	782	last;
431	}	783	}
432	} elsif ($self->{on_read}) {	784	} elsif ($self->{on_read}) {
		785	last unless $len;
		786
433	$self->{on_read}($self);	787	$self->{on_read}($self);
434		788
435	if (	789	if (
436	$self->{eof} # if no further data will arrive
437	&& $len == length $self->{rbuf} # and no data has been consumed	790	$len == length $self->{rbuf} # if no data has been consumed
438	&& !@{ $self->{queue} } # and the queue is still empty	791	&& !@{ $self->{_queue} } # and the queue is still empty
439	&& $self->{on_read} # and we still want to read data	792	&& $self->{on_read} # but we still have on_read
440	) {	793	) {
		794	# no further data will arrive
441	# then no progress can be made	795	# so no progress can be made
442	$! = &Errno::EPIPE; return $self->error;	796	$self->_error (&Errno::EPIPE, 1), return
		797	if $self->{_eof};
		798
		799	last; # more data might arrive
443	}	800	}
444	} else {	801	} else {
445	# read side becomes idle	802	# read side becomes idle
446	delete $self->{rw};	803	delete $self->{_rw} unless $self->{tls};
447	return;	804	last;
448	}	805	}
449	}	806	}
450		807
451	if ($self->{eof}) {	808	if ($self->{_eof}) {
452	$self->_shutdown;	809	if ($self->{on_eof}) {
453	$self->{on_eof}($self)	810	$self->{on_eof}($self)
454	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} };
455	}	820	}
456	}	821	}
457		822
458	=item $handle->on_read ($cb)	823	=item $handle->on_read ($cb)
459		824
…		…
465		830
466	sub on_read {	831	sub on_read {
467	my ($self, $cb) = @_;	832	my ($self, $cb) = @_;
468		833
469	$self->{on_read} = $cb;	834	$self->{on_read} = $cb;
		835	$self->_drain_rbuf if $cb && !$self->{_in_drain};
470	}	836	}
471		837
472	=item $handle->rbuf	838	=item $handle->rbuf
473		839
474	Returns the read buffer (as a modifiable lvalue).	840	Returns the read buffer (as a modifiable lvalue).
…		…
505	interested in (which can be none at all) and return a true value. After returning	871	interested in (which can be none at all) and return a true value. After returning
506	true, it will be removed from the queue.	872	true, it will be removed from the queue.
507		873
508	=cut	874	=cut
509		875
		876	our %RH;
		877
		878	sub register_read_type($$) {
		879	$RH{$_[0]} = $_[1];
		880	}
		881
510	sub push_read {	882	sub push_read {
511	my ($self, $cb) = @_;	883	my $self = shift;
		884	my $cb = pop;
512		885
		886	if (@_) {
		887	my $type = shift;
		888
		889	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		890	->($self, $cb, @_);
		891	}
		892
513	push @{ $self->{queue} }, $cb;	893	push @{ $self->{_queue} }, $cb;
514	$self->_drain_rbuf;	894	$self->_drain_rbuf unless $self->{_in_drain};
515	}	895	}
516		896
517	sub unshift_read {	897	sub unshift_read {
518	my ($self, $cb) = @_;	898	my $self = shift;
		899	my $cb = pop;
519		900
		901	if (@_) {
		902	my $type = shift;
		903
		904	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		905	->($self, $cb, @_);
		906	}
		907
		908
520	push @{ $self->{queue} }, $cb;	909	unshift @{ $self->{_queue} }, $cb;
521	$self->_drain_rbuf;	910	$self->_drain_rbuf unless $self->{_in_drain};
522	}	911	}
523		912
524	=item $handle->push_read_chunk ($len, $cb->($self, $data))	913	=item $handle->push_read (type => @args, $cb)
525		914
526	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	915	=item $handle->unshift_read (type => @args, $cb)
527		916
528	Append the given callback to the end of the queue (C<push_read_chunk>) or	917	Instead of providing a callback that parses the data itself you can chose
529	prepend it (C<unshift_read_chunk>).	918	between a number of predefined parsing formats, for chunks of data, lines
		919	etc.
530		920
531	The callback will be called only once C<$len> bytes have been read, and	921	Predefined types are (if you have ideas for additional types, feel free to
532	these C<$len> bytes will be passed to the callback.	922	drop by and tell us):
533		923
534	=cut	924	=over 4
535		925
536	sub _read_chunk($$) {	926	=item chunk => $octets, $cb->($handle, $data)
		927
		928	Invoke the callback only once C<$octets> bytes have been read. Pass the
		929	data read to the callback. The callback will never be called with less
		930	data.
		931
		932	Example: read 2 bytes.
		933
		934	$handle->push_read (chunk => 2, sub {
		935	warn "yay ", unpack "H*", $_[1];
		936	});
		937
		938	=cut
		939
		940	register_read_type chunk => sub {
537	my ($self, $len, $cb) = @_;	941	my ($self, $cb, $len) = @_;
538		942
539	sub {	943	sub {
540	$len <= length $_[0]{rbuf} or return;	944	$len <= length $_[0]{rbuf} or return;
541	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	945	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
542	1	946	1
543	}	947	}
544	}	948	};
545		949
546	sub push_read_chunk {	950	=item line => [$eol, ]$cb->($handle, $line, $eol)
547	$_[0]->push_read (&_read_chunk);
548	}
549
550
551	sub unshift_read_chunk {
552	$_[0]->unshift_read (&_read_chunk);
553	}
554
555	=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
556
557	=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
558
559	Append the given callback to the end of the queue (C<push_read_line>) or
560	prepend it (C<unshift_read_line>).
561		951
562	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
563	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
564	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
565	the end of line marker as the third argument (C<$eol>).	955	the end of line marker as the third argument (C<$eol>).
…		…
576	Partial lines at the end of the stream will never be returned, as they are	966	Partial lines at the end of the stream will never be returned, as they are
577	not marked by the end of line marker.	967	not marked by the end of line marker.
578		968
579	=cut	969	=cut
580		970
581	sub _read_line($$) {	971	register_read_type line => sub {
582	my $self = shift;	972	my ($self, $cb, $eol) = @_;
583	my $cb = pop;
584	my $eol = @_ ? shift : qr|(\015?\012)|;
585	my $pos;
586		973
		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 {
587	$eol = quotemeta $eol unless ref $eol;	983	$eol = quotemeta $eol unless ref $eol;
588	$eol = qr|^(.*?)($eol)|s;	984	$eol = qr|^(.*?)($eol)|s;
		985
		986	sub {
		987	$_[0]{rbuf} =~ s/$eol// or return;
		988
		989	$cb->($_[0], $1, $2);
		990	1
		991	}
		992	}
		993	};
		994
		995	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		996
		997	Makes a regex match against the regex object C<$accept> and returns
		998	everything up to and including the match.
		999
		1000	Example: read a single line terminated by '\n'.
		1001
		1002	$handle->push_read (regex => qr<\n>, sub { ... });
		1003
		1004	If C<$reject> is given and not undef, then it determines when the data is
		1005	to be rejected: it is matched against the data when the C<$accept> regex
		1006	does not match and generates an C<EBADMSG> error when it matches. This is
		1007	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1008	receive buffer overflow).
		1009
		1010	Example: expect a single decimal number followed by whitespace, reject
		1011	anything else (not the use of an anchor).
		1012
		1013	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1014
		1015	If C<$skip> is given and not C<undef>, then it will be matched against
		1016	the receive buffer when neither C<$accept> nor C<$reject> match,
		1017	and everything preceding and including the match will be accepted
		1018	unconditionally. This is useful to skip large amounts of data that you
		1019	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1020	have to start matching from the beginning. This is purely an optimisation
		1021	and is usually worth only when you expect more than a few kilobytes.
		1022
		1023	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1024	expect the header to be very large (it isn't in practise, but...), we use
		1025	a skip regex to skip initial portions. The skip regex is tricky in that
		1026	it only accepts something not ending in either \015 or \012, as these are
		1027	required for the accept regex.
		1028
		1029	$handle->push_read (regex =>
		1030	qr<\015\012\015\012>,
		1031	undef, # no reject
		1032	qr<^.*[^\015\012]>,
		1033	sub { ... });
		1034
		1035	=cut
		1036
		1037	register_read_type regex => sub {
		1038	my ($self, $cb, $accept, $reject, $skip) = @_;
		1039
		1040	my $data;
		1041	my $rbuf = \$self->{rbuf};
589		1042
590	sub {	1043	sub {
591	$_[0]{rbuf} =~ s/$eol// or return;	1044	# accept
		1045	if ($$rbuf =~ $accept) {
		1046	$data .= substr $$rbuf, 0, $+[0], "";
		1047	$cb->($self, $data);
		1048	return 1;
		1049	}
		1050
		1051	# reject
		1052	if ($reject && $$rbuf =~ $reject) {
		1053	$self->_error (&Errno::EBADMSG);
		1054	}
592		1055
593	$cb->($_[0], $1, $2);	1056	# skip
		1057	if ($skip && $$rbuf =~ $skip) {
		1058	$data .= substr $$rbuf, 0, $+[0], "";
		1059	}
		1060
		1061	()
		1062	}
		1063	};
		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
594	1	1097	1
595	}	1098	}
596	}	1099	};
597		1100
598	sub push_read_line {	1101	=item packstring => $format, $cb->($handle, $string)
599	$_[0]->push_read (&_read_line);
600	}
601		1102
602	sub unshift_read_line {	1103	An octet string prefixed with an encoded length. The encoding C<$format>
603	$_[0]->unshift_read (&_read_line);	1104	uses the same format as a Perl C<pack> format, but must specify a single
604	}	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, $hash_or_arrayref)
		1148
		1149	Reads a JSON object or array, decodes it and passes it to the
		1150	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
		1151
		1152	If a C<json> object was passed to the constructor, then that will be used
		1153	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1154
		1155	This read type uses the incremental parser available with JSON version
		1156	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1157	dependency on your own: this module will load the JSON module, but
		1158	AnyEvent does not depend on it itself.
		1159
		1160	Since JSON texts are fully self-delimiting, the C<json> read and write
		1161	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1162	the C<json> write type description, above, for an actual example.
		1163
		1164	=cut
		1165
		1166	register_read_type json => sub {
		1167	my ($self, $cb) = @_;
		1168
		1169	require JSON;
		1170
		1171	my $data;
		1172	my $rbuf = \$self->{rbuf};
		1173
		1174	my $json = $self->{json} ||= JSON->new->utf8;
		1175
		1176	sub {
		1177	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
		1178
		1179	if ($ref) {
		1180	$self->{rbuf} = $json->incr_text;
		1181	$json->incr_text = "";
		1182	$cb->($self, $ref);
		1183
		1184	1
		1185	} elsif ($@) {
		1186	# error case
		1187	$json->incr_skip;
		1188
		1189	$self->{rbuf} = $json->incr_text;
		1190	$json->incr_text = "";
		1191
		1192	$self->_error (&Errno::EBADMSG);
		1193	()
		1194
		1195	} else {
		1196	$self->{rbuf} = "";
		1197	()
		1198	}
		1199	}
		1200	};
		1201
		1202	=item storable => $cb->($handle, $ref)
		1203
		1204	Deserialises a L<Storable> frozen representation as written by the
		1205	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1206	data).
		1207
		1208	Raises C<EBADMSG> error if the data could not be decoded.
		1209
		1210	=cut
		1211
		1212	register_read_type storable => sub {
		1213	my ($self, $cb) = @_;
		1214
		1215	require Storable;
		1216
		1217	sub {
		1218	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1219	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1220	or return;
		1221
		1222	my $format = length pack "w", $len;
		1223
		1224	# bypass unshift if we already have the remaining chunk
		1225	if ($format + $len <= length $_[0]{rbuf}) {
		1226	my $data = substr $_[0]{rbuf}, $format, $len;
		1227	substr $_[0]{rbuf}, 0, $format + $len, "";
		1228	$cb->($_[0], Storable::thaw ($data));
		1229	} else {
		1230	# remove prefix
		1231	substr $_[0]{rbuf}, 0, $format, "";
		1232
		1233	# read remaining chunk
		1234	$_[0]->unshift_read (chunk => $len, sub {
		1235	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1236	$cb->($_[0], $ref);
		1237	} else {
		1238	$self->_error (&Errno::EBADMSG);
		1239	}
		1240	});
		1241	}
		1242
		1243	1
		1244	}
		1245	};
		1246
		1247	=back
		1248
		1249	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1250
		1251	This function (not method) lets you add your own types to C<push_read>.
		1252
		1253	Whenever the given C<type> is used, C<push_read> will invoke the code
		1254	reference with the handle object, the callback and the remaining
		1255	arguments.
		1256
		1257	The code reference is supposed to return a callback (usually a closure)
		1258	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1259
		1260	It should invoke the passed callback when it is done reading (remember to
		1261	pass C<$handle> as first argument as all other callbacks do that).
		1262
		1263	Note that this is a function, and all types registered this way will be
		1264	global, so try to use unique names.
		1265
		1266	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1267	search for C<register_read_type>)).
605		1268
606	=item $handle->stop_read	1269	=item $handle->stop_read
607		1270
608	=item $handle->start_read	1271	=item $handle->start_read
609		1272
610	In rare cases you actually do not want to read anything from the	1273	In rare cases you actually do not want to read anything from the
611	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1274	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
612	any queued callbacks will be executed then. To start reading again, call	1275	any queued callbacks will be executed then. To start reading again, call
613	C<start_read>.	1276	C<start_read>.
614		1277
		1278	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1279	you change the C<on_read> callback or push/unshift a read callback, and it
		1280	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1281	there are any read requests in the queue.
		1282
		1283	These methods will have no effect when in TLS mode (as TLS doesn't support
		1284	half-duplex connections).
		1285
615	=cut	1286	=cut
616		1287
617	sub stop_read {	1288	sub stop_read {
618	my ($self) = @_;	1289	my ($self) = @_;
619		1290
620	delete $self->{rw};	1291	delete $self->{_rw} unless $self->{tls};
621	}	1292	}
622		1293
623	sub start_read {	1294	sub start_read {
624	my ($self) = @_;	1295	my ($self) = @_;
625		1296
626	unless ($self->{rw} || $self->{eof}) {	1297	unless ($self->{_rw} || $self->{_eof}) {
627	Scalar::Util::weaken $self;	1298	Scalar::Util::weaken $self;
628		1299
629	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1300	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
630	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1301	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
631	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1302	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
632		1303
633	if ($len > 0) {	1304	if ($len > 0) {
634	$self->{filter_r}	1305	$self->{_activity} = AnyEvent->now;
635	? $self->{filter_r}->($self, $rbuf)	1306
636	: $self->_drain_rbuf;	1307	if ($self->{tls}) {
		1308	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1309
		1310	&_dotls ($self);
		1311	} else {
		1312	$self->_drain_rbuf unless $self->{_in_drain};
		1313	}
637		1314
638	} elsif (defined $len) {	1315	} elsif (defined $len) {
639	delete $self->{rw};	1316	delete $self->{_rw};
640	$self->{eof} = 1;	1317	$self->{_eof} = 1;
641	$self->_drain_rbuf;	1318	$self->_drain_rbuf unless $self->{_in_drain};
642		1319
643	} elsif ($! != EAGAIN && $! != EINTR) {	1320	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
644	return $self->error;	1321	return $self->_error ($!, 1);
645	}	1322	}
646	});	1323	});
647	}	1324	}
648	}	1325	}
649		1326
		1327	# poll the write BIO and send the data if applicable
650	sub _dotls {	1328	sub _dotls {
651	my ($self) = @_;	1329	my ($self) = @_;
652		1330
		1331	my $tmp;
		1332
653	if (length $self->{tls_wbuf}) {	1333	if (length $self->{_tls_wbuf}) {
654	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf})) > 0) {	1334	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
655	substr $self->{tls_wbuf}, 0, $len, "";	1335	substr $self->{_tls_wbuf}, 0, $tmp, "";
656	}	1336	}
657	}	1337	}
658		1338
659	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) {	1339	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1340	unless (length $tmp) {
		1341	# let's treat SSL-eof as we treat normal EOF
		1342	delete $self->{_rw};
		1343	$self->{_eof} = 1;
		1344	&_freetls;
		1345	}
		1346
		1347	$self->{rbuf} .= $tmp;
		1348	$self->_drain_rbuf unless $self->{_in_drain};
		1349	$self->{tls} or return; # tls session might have gone away in callback
		1350	}
		1351
		1352	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1353
		1354	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
		1355	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
		1356	return $self->_error ($!, 1);
		1357	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
		1358	return $self->_error (&Errno::EIO, 1);
		1359	}
		1360
		1361	# all other errors are fine for our purposes
		1362	}
		1363
		1364	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
660	$self->{wbuf} .= $buf;	1365	$self->{wbuf} .= $tmp;
661	$self->_drain_wbuf;	1366	$self->_drain_wbuf;
662	}
663
664	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
665	$self->{rbuf} .= $buf;
666	$self->_drain_rbuf;
667	}
668
669	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
670
671	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
672	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
673	$self->error;
674	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
675	$! = &Errno::EIO;
676	$self->error;
677	}
678
679	# all others are fine for our purposes
680	}	1367	}
681	}	1368	}
682		1369
683	=item $handle->starttls ($tls[, $tls_ctx])	1370	=item $handle->starttls ($tls[, $tls_ctx])
684		1371
…		…
690	C<"connect">, C<"accept"> or an existing Net::SSLeay object).	1377	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
691		1378
692	The second argument is the optional C<Net::SSLeay::CTX> object that is	1379	The second argument is the optional C<Net::SSLeay::CTX> object that is
693	used when AnyEvent::Handle has to create its own TLS connection object.	1380	used when AnyEvent::Handle has to create its own TLS connection object.
694		1381
695	=cut	1382	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1383	call and can be used or changed to your liking. Note that the handshake
		1384	might have already started when this function returns.
696		1385
697	# TODO: maybe document...	1386	If it an error to start a TLS handshake more than once per
		1387	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1388
		1389	=cut
		1390
698	sub starttls {	1391	sub starttls {
699	my ($self, $ssl, $ctx) = @_;	1392	my ($self, $ssl, $ctx) = @_;
700		1393
701	$self->stoptls;	1394	require Net::SSLeay;
702		1395
		1396	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1397	if $self->{tls};
		1398
703	if ($ssl eq "accept") {	1399	if ($ssl eq "accept") {
704	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1400	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
705	Net::SSLeay::set_accept_state ($ssl);	1401	Net::SSLeay::set_accept_state ($ssl);
706	} elsif ($ssl eq "connect") {	1402	} elsif ($ssl eq "connect") {
707	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1403	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
…		…
713	# basically, this is deep magic (because SSL_read should have the same issues)	1409	# basically, this is deep magic (because SSL_read should have the same issues)
714	# but the openssl maintainers basically said: "trust us, it just works".	1410	# but the openssl maintainers basically said: "trust us, it just works".
715	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1411	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
716	# and mismaintained ssleay-module doesn't even offer them).	1412	# and mismaintained ssleay-module doesn't even offer them).
717	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1413	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1414	#
		1415	# in short: this is a mess.
		1416	#
		1417	# note that we do not try to keep the length constant between writes as we are required to do.
		1418	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1419	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1420	# have identity issues in that area.
718	Net::SSLeay::CTX_set_mode ($self->{tls},	1421	Net::SSLeay::CTX_set_mode ($self->{tls},
719	(eval { Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1422	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
720	| (eval { Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1423	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
721		1424
722	$self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1425	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
723	$self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1426	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
724		1427
725	Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio});	1428	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
726		1429
727	$self->{filter_w} = sub {	1430	&_dotls; # need to trigger the initial handshake
728	$_[0]{tls_wbuf} .= ${$_[1]};	1431	$self->start_read; # make sure we actually do read
729	&_dotls;
730	};
731	$self->{filter_r} = sub {
732	Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
733	&_dotls;
734	};
735	}	1432	}
736		1433
737	=item $handle->stoptls	1434	=item $handle->stoptls
738		1435
739	Destroys the SSL connection, if any. Partial read or write data will be	1436	Shuts down the SSL connection - this makes a proper EOF handshake by
740	lost.	1437	sending a close notify to the other side, but since OpenSSL doesn't
		1438	support non-blocking shut downs, it is not possible to re-use the stream
		1439	afterwards.
741		1440
742	=cut	1441	=cut
743		1442
744	sub stoptls {	1443	sub stoptls {
745	my ($self) = @_;	1444	my ($self) = @_;
746		1445
		1446	if ($self->{tls}) {
		1447	Net::SSLeay::shutdown ($self->{tls});
		1448
		1449	&_dotls;
		1450
		1451	# we don't give a shit. no, we do, but we can't. no...
		1452	# we, we... have to use openssl :/
		1453	&_freetls;
		1454	}
		1455	}
		1456
		1457	sub _freetls {
		1458	my ($self) = @_;
		1459
		1460	return unless $self->{tls};
		1461
747	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1462	Net::SSLeay::free (delete $self->{tls});
748	delete $self->{tls_rbio};	1463
749	delete $self->{tls_wbio};	1464	delete @$self{qw(_rbio _wbio _tls_wbuf)};
750	delete $self->{tls_wbuf};
751	delete $self->{filter_r};
752	delete $self->{filter_w};
753	}	1465	}
754		1466
755	sub DESTROY {	1467	sub DESTROY {
756	my $self = shift;	1468	my $self = shift;
757		1469
758	$self->stoptls;	1470	&_freetls;
		1471
		1472	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1473
		1474	if ($linger && length $self->{wbuf}) {
		1475	my $fh = delete $self->{fh};
		1476	my $wbuf = delete $self->{wbuf};
		1477
		1478	my @linger;
		1479
		1480	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1481	my $len = syswrite $fh, $wbuf, length $wbuf;
		1482
		1483	if ($len > 0) {
		1484	substr $wbuf, 0, $len, "";
		1485	} else {
		1486	@linger = (); # end
		1487	}
		1488	});
		1489	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1490	@linger = ();
		1491	});
		1492	}
		1493	}
		1494
		1495	=item $handle->destroy
		1496
		1497	Shuts down the handle object as much as possible - this call ensures that
		1498	no further callbacks will be invoked and resources will be freed as much
		1499	as possible. You must not call any methods on the object afterwards.
		1500
		1501	Normally, you can just "forget" any references to an AnyEvent::Handle
		1502	object and it will simply shut down. This works in fatal error and EOF
		1503	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1504	callback, so when you want to destroy the AnyEvent::Handle object from
		1505	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1506	that case.
		1507
		1508	The handle might still linger in the background and write out remaining
		1509	data, as specified by the C<linger> option, however.
		1510
		1511	=cut
		1512
		1513	sub destroy {
		1514	my ($self) = @_;
		1515
		1516	$self->DESTROY;
		1517	%$self = ();
759	}	1518	}
760		1519
761	=item AnyEvent::Handle::TLS_CTX	1520	=item AnyEvent::Handle::TLS_CTX
762		1521
763	This function creates and returns the Net::SSLeay::CTX object used by	1522	This function creates and returns the Net::SSLeay::CTX object used by
…		…
793	}	1552	}
794	}	1553	}
795		1554
796	=back	1555	=back
797		1556
		1557
		1558	=head1 NONFREQUENTLY ASKED QUESTIONS
		1559
		1560	=over 4
		1561
		1562	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1563	still get further invocations!
		1564
		1565	That's because AnyEvent::Handle keeps a reference to itself when handling
		1566	read or write callbacks.
		1567
		1568	It is only safe to "forget" the reference inside EOF or error callbacks,
		1569	from within all other callbacks, you need to explicitly call the C<<
		1570	->destroy >> method.
		1571
		1572	=item I get different callback invocations in TLS mode/Why can't I pause
		1573	reading?
		1574
		1575	Unlike, say, TCP, TLS connections do not consist of two independent
		1576	communication channels, one for each direction. Or put differently. The
		1577	read and write directions are not independent of each other: you cannot
		1578	write data unless you are also prepared to read, and vice versa.
		1579
		1580	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1581	callback invocations when you are not expecting any read data - the reason
		1582	is that AnyEvent::Handle always reads in TLS mode.
		1583
		1584	During the connection, you have to make sure that you always have a
		1585	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1586	connection (or when you no longer want to use it) you can call the
		1587	C<destroy> method.
		1588
		1589	=item How do I read data until the other side closes the connection?
		1590
		1591	If you just want to read your data into a perl scalar, the easiest way
		1592	to achieve this is by setting an C<on_read> callback that does nothing,
		1593	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1594	will be in C<$_[0]{rbuf}>:
		1595
		1596	$handle->on_read (sub { });
		1597	$handle->on_eof (undef);
		1598	$handle->on_error (sub {
		1599	my $data = delete $_[0]{rbuf};
		1600	undef $handle;
		1601	});
		1602
		1603	The reason to use C<on_error> is that TCP connections, due to latencies
		1604	and packets loss, might get closed quite violently with an error, when in
		1605	fact, all data has been received.
		1606
		1607	It is usually better to use acknowledgements when transferring data,
		1608	to make sure the other side hasn't just died and you got the data
		1609	intact. This is also one reason why so many internet protocols have an
		1610	explicit QUIT command.
		1611
		1612	=item I don't want to destroy the handle too early - how do I wait until
		1613	all data has been written?
		1614
		1615	After writing your last bits of data, set the C<on_drain> callback
		1616	and destroy the handle in there - with the default setting of
		1617	C<low_water_mark> this will be called precisely when all data has been
		1618	written to the socket:
		1619
		1620	$handle->push_write (...);
		1621	$handle->on_drain (sub {
		1622	warn "all data submitted to the kernel\n";
		1623	undef $handle;
		1624	});
		1625
		1626	=back
		1627
		1628
		1629	=head1 SUBCLASSING AnyEvent::Handle
		1630
		1631	In many cases, you might want to subclass AnyEvent::Handle.
		1632
		1633	To make this easier, a given version of AnyEvent::Handle uses these
		1634	conventions:
		1635
		1636	=over 4
		1637
		1638	=item * all constructor arguments become object members.
		1639
		1640	At least initially, when you pass a C<tls>-argument to the constructor it
		1641	will end up in C<< $handle->{tls} >>. Those members might be changed or
		1642	mutated later on (for example C<tls> will hold the TLS connection object).
		1643
		1644	=item * other object member names are prefixed with an C<_>.
		1645
		1646	All object members not explicitly documented (internal use) are prefixed
		1647	with an underscore character, so the remaining non-C<_>-namespace is free
		1648	for use for subclasses.
		1649
		1650	=item * all members not documented here and not prefixed with an underscore
		1651	are free to use in subclasses.
		1652
		1653	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1654	member variables, but thats just life, at least it is documented.
		1655
		1656	=back
		1657
798	=head1 AUTHOR	1658	=head1 AUTHOR
799		1659
800	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	1660	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
801		1661
802	=cut	1662	=cut

Diff Legend

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