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 1.13 by elmex, Thu May 15 13:32:19 2008 UTC vs.
Revision 1.93 by root, Wed Oct 1 14:49:23 2008 UTC

1	package AnyEvent::Handle;	1	package AnyEvent::Handle;
2		2
3	no warnings;	3	no warnings;
4	use strict;	4	use strict qw(subs vars);
5		5
6	use AnyEvent ();	6	use AnyEvent ();
7	use AnyEvent::Util ();	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
10	use Fcntl ();	10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;	11	use Errno qw(EAGAIN EINTR);
12		12
13	=head1 NAME	13	=head1 NAME
14		14
15	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16		16
17	=cut	17	=cut
18		18
19	our $VERSION = '0.02';	19	our $VERSION = 4.3;
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
25		25
26	my $cv = AnyEvent->condvar;	26	my $cv = AnyEvent->condvar;
27		27
28	my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	28	my $handle =
29
30	#TODO
31
32	# or use the constructor to pass the callback:
33
34	my $ae_fh2 =
35	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
36	fh => \*STDIN,	30	fh => \*STDIN,
37	on_eof => sub {	31	on_eof => sub {
38	$cv->broadcast;	32	$cv->broadcast;
39	},	33	},
40	#TODO
41	);	34	);
42		35
43	$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	$cv->recv;
44		47
45	=head1 DESCRIPTION	48	=head1 DESCRIPTION
46		49
47	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
48	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
49	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
50		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
51	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
52	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
53	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
54		60
55	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
56	argument.	62	argument.
57		63
		64	=head2 SIGPIPE is not handled by this module
		65
		66	SIGPIPE is not handled by this module, so one of the practical
		67	requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} =
		68	'IGNORE'>). At least, this is highly recommend in a networked program: If
		69	you use AnyEvent::Handle in a filter program (like sort), exiting on
		70	SIGPIPE is probably the right thing to do.
		71
58	=head1 METHODS	72	=head1 METHODS
59		73
60	=over 4	74	=over 4
61		75
62	=item B<new (%args)>	76	=item B<new (%args)>
…		…
67		81
68	=item fh => $filehandle [MANDATORY]	82	=item fh => $filehandle [MANDATORY]
69		83
70	The filehandle this L<AnyEvent::Handle> object will operate on.	84	The filehandle this L<AnyEvent::Handle> object will operate on.
71		85
72	NOTE: The filehandle will be set to non-blocking (using	86	NOTE: The filehandle will be set to non-blocking mode (using
73	AnyEvent::Util::fh_nonblocking).	87	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		88	that mode.
74		89
75	=item on_eof => $cb->($self) [MANDATORY]
76
77	Set the callback to be called on EOF.
78
79	=item on_error => $cb->($self)	90	=item on_eof => $cb->($handle)
80		91
		92	Set the callback to be called when an end-of-file condition is detected,
		93	i.e. in the case of a socket, when the other side has closed the
		94	connection cleanly.
		95
		96	For sockets, this just means that the other side has stopped sending data,
		97	you can still try to write data, and, in fact, one can return from the eof
		98	callback and continue writing data, as only the read part has been shut
		99	down.
		100
		101	While not mandatory, it is I<highly> recommended to set an eof callback,
		102	otherwise you might end up with a closed socket while you are still
		103	waiting for data.
		104
		105	If an EOF condition has been detected but no C<on_eof> callback has been
		106	set, then a fatal error will be raised with C<$!> set to <0>.
		107
		108	=item on_error => $cb->($handle, $fatal)
		109
81	This is the fatal error callback, that is called when, well, a fatal error	110	This is the error callback, which is called when, well, some error
82	ocurs, such as not being able to resolve the hostname, failure to connect	111	occured, such as not being able to resolve the hostname, failure to
83	or a read error.	112	connect or a read error.
84		113
85	The object will not be in a usable state when this callback has been	114	Some errors are fatal (which is indicated by C<$fatal> being true). On
86	called.	115	fatal errors the handle object will be shut down and will not be usable
		116	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		117	errors are an EOF condition with active (but unsatisifable) read watchers
		118	(C<EPIPE>) or I/O errors.
		119
		120	Non-fatal errors can be retried by simply returning, but it is recommended
		121	to simply ignore this parameter and instead abondon the handle object
		122	when this callback is invoked. Examples of non-fatal errors are timeouts
		123	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
87		124
88	On callback entrance, the value of C<$!> contains the operating system	125	On callback entrance, the value of C<$!> contains the operating system
89	error (or C<ENOSPC> or C<EPIPE>).	126	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
90		127
91	While not mandatory, it is I<highly> recommended to set this callback, as	128	While not mandatory, it is I<highly> recommended to set this callback, as
92	you will not be notified of errors otherwise. The default simply calls	129	you will not be notified of errors otherwise. The default simply calls
93	die.	130	C<croak>.
94		131
95	=item on_read => $cb->($self)	132	=item on_read => $cb->($handle)
96		133
97	This sets the default read callback, which is called when data arrives	134	This sets the default read callback, which is called when data arrives
98	and no read request is in the queue.	135	and no read request is in the queue (unlike read queue callbacks, this
		136	callback will only be called when at least one octet of data is in the
		137	read buffer).
99		138
100	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	139	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
101	method or acces sthe C<$self->{rbuf}> member directly.	140	method or access the C<$handle->{rbuf}> member directly.
102		141
103	When an EOF condition is detected then AnyEvent::Handle will first try to	142	When an EOF condition is detected then AnyEvent::Handle will first try to
104	feed all the remaining data to the queued callbacks and C<on_read> before	143	feed all the remaining data to the queued callbacks and C<on_read> before
105	calling the C<on_eof> callback. If no progress can be made, then a fatal	144	calling the C<on_eof> callback. If no progress can be made, then a fatal
106	error will be raised (with C<$!> set to C<EPIPE>).	145	error will be raised (with C<$!> set to C<EPIPE>).
107		146
108	=item on_drain => $cb->()	147	=item on_drain => $cb->($handle)
109		148
110	This sets the callback that is called when the write buffer becomes empty	149	This sets the callback that is called when the write buffer becomes empty
111	(or when the callback is set and the buffer is empty already).	150	(or when the callback is set and the buffer is empty already).
112		151
113	To append to the write buffer, use the C<< ->push_write >> method.	152	To append to the write buffer, use the C<< ->push_write >> method.
114		153
		154	This callback is useful when you don't want to put all of your write data
		155	into the queue at once, for example, when you want to write the contents
		156	of some file to the socket you might not want to read the whole file into
		157	memory and push it into the queue, but instead only read more data from
		158	the file when the write queue becomes empty.
		159
		160	=item timeout => $fractional_seconds
		161
		162	If non-zero, then this enables an "inactivity" timeout: whenever this many
		163	seconds pass without a successful read or write on the underlying file
		164	handle, the C<on_timeout> callback will be invoked (and if that one is
		165	missing, a non-fatal C<ETIMEDOUT> error will be raised).
		166
		167	Note that timeout processing is also active when you currently do not have
		168	any outstanding read or write requests: If you plan to keep the connection
		169	idle then you should disable the timout temporarily or ignore the timeout
		170	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		171	restart the timeout.
		172
		173	Zero (the default) disables this timeout.
		174
		175	=item on_timeout => $cb->($handle)
		176
		177	Called whenever the inactivity timeout passes. If you return from this
		178	callback, then the timeout will be reset as if some activity had happened,
		179	so this condition is not fatal in any way.
		180
115	=item rbuf_max => <bytes>	181	=item rbuf_max => <bytes>
116		182
117	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	183	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
118	when the read buffer ever (strictly) exceeds this size. This is useful to	184	when the read buffer ever (strictly) exceeds this size. This is useful to
119	avoid denial-of-service attacks.	185	avoid some forms of denial-of-service attacks.
120		186
121	For example, a server accepting connections from untrusted sources should	187	For example, a server accepting connections from untrusted sources should
122	be configured to accept only so-and-so much data that it cannot act on	188	be configured to accept only so-and-so much data that it cannot act on
123	(for example, when expecting a line, an attacker could send an unlimited	189	(for example, when expecting a line, an attacker could send an unlimited
124	amount of data without a callback ever being called as long as the line	190	amount of data without a callback ever being called as long as the line
125	isn't finished).	191	isn't finished).
126		192
		193	=item autocork => <boolean>
		194
		195	When disabled (the default), then C<push_write> will try to immediately
		196	write the data to the handle, if possible. This avoids having to register
		197	a write watcher and wait for the next event loop iteration, but can
		198	be inefficient if you write multiple small chunks (on the wire, this
		199	disadvantage is usually avoided by your kernel's nagle algorithm, see
		200	C<no_delay>, but this option can save costly syscalls).
		201
		202	When enabled, then writes will always be queued till the next event loop
		203	iteration. This is efficient when you do many small writes per iteration,
		204	but less efficient when you do a single write only per iteration (or when
		205	the write buffer often is full). It also increases write latency.
		206
		207	=item no_delay => <boolean>
		208
		209	When doing small writes on sockets, your operating system kernel might
		210	wait a bit for more data before actually sending it out. This is called
		211	the Nagle algorithm, and usually it is beneficial.
		212
		213	In some situations you want as low a delay as possible, which can be
		214	accomplishd by setting this option to a true value.
		215
		216	The default is your opertaing system's default behaviour (most likely
		217	enabled), this option explicitly enables or disables it, if possible.
		218
127	=item read_size => <bytes>	219	=item read_size => <bytes>
128		220
129	The default read block size (the amount of bytes this module will try to read	221	The default read block size (the amount of bytes this module will
130	on each [loop iteration). Default: C<4096>.	222	try to read during each loop iteration, which affects memory
		223	requirements). Default: C<8192>.
131		224
132	=item low_water_mark => <bytes>	225	=item low_water_mark => <bytes>
133		226
134	Sets the amount of bytes (default: C<0>) that make up an "empty" write	227	Sets the amount of bytes (default: C<0>) that make up an "empty" write
135	buffer: If the write reaches this size or gets even samller it is	228	buffer: If the write reaches this size or gets even samller it is
136	considered empty.	229	considered empty.
137		230
		231	Sometimes it can be beneficial (for performance reasons) to add data to
		232	the write buffer before it is fully drained, but this is a rare case, as
		233	the operating system kernel usually buffers data as well, so the default
		234	is good in almost all cases.
		235
		236	=item linger => <seconds>
		237
		238	If non-zero (default: C<3600>), then the destructor of the
		239	AnyEvent::Handle object will check whether there is still outstanding
		240	write data and will install a watcher that will write this data to the
		241	socket. No errors will be reported (this mostly matches how the operating
		242	system treats outstanding data at socket close time).
		243
		244	This will not work for partial TLS data that could not be encoded
		245	yet. This data will be lost. Calling the C<stoptls> method in time might
		246	help.
		247
		248	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
		249
		250	When this parameter is given, it enables TLS (SSL) mode, that means
		251	AnyEvent will start a TLS handshake as soon as the conenction has been
		252	established and will transparently encrypt/decrypt data afterwards.
		253
		254	TLS mode requires Net::SSLeay to be installed (it will be loaded
		255	automatically when you try to create a TLS handle): this module doesn't
		256	have a dependency on that module, so if your module requires it, you have
		257	to add the dependency yourself.
		258
		259	Unlike TCP, TLS has a server and client side: for the TLS server side, use
		260	C<accept>, and for the TLS client side of a connection, use C<connect>
		261	mode.
		262
		263	You can also provide your own TLS connection object, but you have
		264	to make sure that you call either C<Net::SSLeay::set_connect_state>
		265	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		266	AnyEvent::Handle.
		267
		268	See the C<< ->starttls >> method for when need to start TLS negotiation later.
		269
		270	=item tls_ctx => $ssl_ctx
		271
		272	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
		273	(unless a connection object was specified directly). If this parameter is
		274	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		275
		276	=item json => JSON or JSON::XS object
		277
		278	This is the json coder object used by the C<json> read and write types.
		279
		280	If you don't supply it, then AnyEvent::Handle will create and use a
		281	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		282	texts.
		283
		284	Note that you are responsible to depend on the JSON module if you want to
		285	use this functionality, as AnyEvent does not have a dependency itself.
		286
138	=back	287	=back
139		288
140	=cut	289	=cut
141		290
142	sub new {	291	sub new {
…		…
146		295
147	$self->{fh} or Carp::croak "mandatory argument fh is missing";	296	$self->{fh} or Carp::croak "mandatory argument fh is missing";
148		297
149	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	298	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
150		299
151	$self->on_eof ((delete $self->{on_eof} ) or Carp::croak "mandatory argument on_eof is missing");	300	if ($self->{tls}) {
		301	require Net::SSLeay;
		302	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
		303	}
152		304
153	$self->on_error (delete $self->{on_error}) if $self->{on_error};	305	$self->{_activity} = AnyEvent->now;
		306	$self->_timeout;
		307
154	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	308	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
155	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	309	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
156		310
157	$self->start_read;	311	$self->start_read
		312	if $self->{on_read};
158		313
159	$self	314	$self
160	}	315	}
161		316
162	sub _shutdown {	317	sub _shutdown {
163	my ($self) = @_;	318	my ($self) = @_;
164		319
		320	delete $self->{_tw};
165	delete $self->{rw};	321	delete $self->{_rw};
166	delete $self->{ww};	322	delete $self->{_ww};
167	delete $self->{fh};	323	delete $self->{fh};
168	}
169		324
		325	&_freetls;
		326
		327	delete $self->{on_read};
		328	delete $self->{_queue};
		329	}
		330
170	sub error {	331	sub _error {
171	my ($self) = @_;	332	my ($self, $errno, $fatal) = @_;
172		333
173	{
174	local $!;
175	$self->_shutdown;	334	$self->_shutdown
176	}	335	if $fatal;
		336
		337	$! = $errno;
177		338
178	if ($self->{on_error}) {	339	if ($self->{on_error}) {
179	$self->{on_error}($self);	340	$self->{on_error}($self, $fatal);
180	} else {	341	} else {
181	die "AnyEvent::Handle uncaught fatal error: $!";	342	Carp::croak "AnyEvent::Handle uncaught error: $!";
182	}	343	}
183	}	344	}
184		345
185	=item $fh = $handle->fh	346	=item $fh = $handle->fh
186		347
187	This method returns the filehandle of the L<AnyEvent::Handle> object.	348	This method returns the file handle used to create the L<AnyEvent::Handle> object.
188		349
189	=cut	350	=cut
190		351
191	sub fh { $_[0]->{fh} }	352	sub fh { $_[0]{fh} }
192		353
193	=item $handle->on_error ($cb)	354	=item $handle->on_error ($cb)
194		355
195	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	356	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
196		357
…		…
208		369
209	sub on_eof {	370	sub on_eof {
210	$_[0]{on_eof} = $_[1];	371	$_[0]{on_eof} = $_[1];
211	}	372	}
212		373
		374	=item $handle->on_timeout ($cb)
		375
		376	Replace the current C<on_timeout> callback, or disables the callback (but
		377	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
		378	argument and method.
		379
		380	=cut
		381
		382	sub on_timeout {
		383	$_[0]{on_timeout} = $_[1];
		384	}
		385
		386	=item $handle->autocork ($boolean)
		387
		388	Enables or disables the current autocork behaviour (see C<autocork>
		389	constructor argument).
		390
		391	=cut
		392
		393	=item $handle->no_delay ($boolean)
		394
		395	Enables or disables the C<no_delay> setting (see constructor argument of
		396	the same name for details).
		397
		398	=cut
		399
		400	sub no_delay {
		401	$_[0]{no_delay} = $_[1];
		402
		403	eval {
		404	local $SIG{__DIE__};
		405	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		406	};
		407	}
		408
		409	#############################################################################
		410
		411	=item $handle->timeout ($seconds)
		412
		413	Configures (or disables) the inactivity timeout.
		414
		415	=cut
		416
		417	sub timeout {
		418	my ($self, $timeout) = @_;
		419
		420	$self->{timeout} = $timeout;
		421	$self->_timeout;
		422	}
		423
		424	# reset the timeout watcher, as neccessary
		425	# also check for time-outs
		426	sub _timeout {
		427	my ($self) = @_;
		428
		429	if ($self->{timeout}) {
		430	my $NOW = AnyEvent->now;
		431
		432	# when would the timeout trigger?
		433	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		434
		435	# now or in the past already?
		436	if ($after <= 0) {
		437	$self->{_activity} = $NOW;
		438
		439	if ($self->{on_timeout}) {
		440	$self->{on_timeout}($self);
		441	} else {
		442	$self->_error (&Errno::ETIMEDOUT);
		443	}
		444
		445	# callback could have changed timeout value, optimise
		446	return unless $self->{timeout};
		447
		448	# calculate new after
		449	$after = $self->{timeout};
		450	}
		451
		452	Scalar::Util::weaken $self;
		453	return unless $self; # ->error could have destroyed $self
		454
		455	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		456	delete $self->{_tw};
		457	$self->_timeout;
		458	});
		459	} else {
		460	delete $self->{_tw};
		461	}
		462	}
		463
213	#############################################################################	464	#############################################################################
214		465
215	=back	466	=back
216		467
217	=head2 WRITE QUEUE	468	=head2 WRITE QUEUE
…		…
220	for reading.	471	for reading.
221		472
222	The write queue is very simple: you can add data to its end, and	473	The write queue is very simple: you can add data to its end, and
223	AnyEvent::Handle will automatically try to get rid of it for you.	474	AnyEvent::Handle will automatically try to get rid of it for you.
224		475
225	When data could be writtena nd the write buffer is shorter then the low	476	When data could be written and the write buffer is shorter then the low
226	water mark, the C<on_drain> callback will be invoked.	477	water mark, the C<on_drain> callback will be invoked.
227		478
228	=over 4	479	=over 4
229		480
230	=item $handle->on_drain ($cb)	481	=item $handle->on_drain ($cb)
…		…
238	my ($self, $cb) = @_;	489	my ($self, $cb) = @_;
239		490
240	$self->{on_drain} = $cb;	491	$self->{on_drain} = $cb;
241		492
242	$cb->($self)	493	$cb->($self)
243	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	494	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
244	}	495	}
245		496
246	=item $handle->push_write ($data)	497	=item $handle->push_write ($data)
247		498
248	Queues the given scalar to be written. You can push as much data as you	499	Queues the given scalar to be written. You can push as much data as you
249	want (only limited by the available memory), as C<AnyEvent::Handle>	500	want (only limited by the available memory), as C<AnyEvent::Handle>
250	buffers it independently of the kernel.	501	buffers it independently of the kernel.
251		502
252	=cut	503	=cut
253		504
254	sub push_write {	505	sub _drain_wbuf {
255	my ($self, $data) = @_;	506	my ($self) = @_;
256		507
257	$self->{wbuf} .= $data;	508	if (!$self->{_ww} && length $self->{wbuf}) {
258		509
259	unless ($self->{ww}) {
260	Scalar::Util::weaken $self;	510	Scalar::Util::weaken $self;
		511
261	my $cb = sub {	512	my $cb = sub {
262	my $len = syswrite $self->{fh}, $self->{wbuf};	513	my $len = syswrite $self->{fh}, $self->{wbuf};
263		514
264	if ($len > 0) {	515	if ($len >= 0) {
265	substr $self->{wbuf}, 0, $len, "";	516	substr $self->{wbuf}, 0, $len, "";
266		517
		518	$self->{_activity} = AnyEvent->now;
267		519
268	$self->{on_drain}($self)	520	$self->{on_drain}($self)
269	if $self->{low_water_mark} >= length $self->{wbuf}	521	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
270	&& $self->{on_drain};	522	&& $self->{on_drain};
271		523
272	delete $self->{ww} unless length $self->{wbuf};	524	delete $self->{_ww} unless length $self->{wbuf};
273	} elsif ($! != EAGAIN && $! != EINTR) {	525	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
274	$self->error;	526	$self->_error ($!, 1);
275	}	527	}
276	};	528	};
277		529
		530	# try to write data immediately
		531	$cb->() unless $self->{autocork};
		532
		533	# if still data left in wbuf, we need to poll
278	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	534	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
279		535	if length $self->{wbuf};
280	$cb->($self);
281	};	536	};
282	}	537	}
		538
		539	our %WH;
		540
		541	sub register_write_type($$) {
		542	$WH{$_[0]} = $_[1];
		543	}
		544
		545	sub push_write {
		546	my $self = shift;
		547
		548	if (@_ > 1) {
		549	my $type = shift;
		550
		551	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		552	->($self, @_);
		553	}
		554
		555	if ($self->{tls}) {
		556	$self->{_tls_wbuf} .= $_[0];
		557	&_dotls ($self);
		558	} else {
		559	$self->{wbuf} .= $_[0];
		560	$self->_drain_wbuf;
		561	}
		562	}
		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	sprintf "%d:%s,", (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
283		673
284	#############################################################################	674	#############################################################################
285		675
286	=back	676	=back
287		677
…		…
294	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
295	a queue.	685	a queue.
296		686
297	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
298	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
299	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
300	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).
301		692
302	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
303	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
304	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
305	below).	696	done its job (see C<push_read>, below).
306		697
307	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
308	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.
309		700
310	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
311	the specified number of bytes which give an XML datagram.	702	the specified number of bytes which give an XML datagram.
312		703
313	# in the default state, expect some header bytes	704	# in the default state, expect some header bytes
314	$handle->on_read (sub {	705	$handle->on_read (sub {
315	# 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)
316	shift->unshift_read_chunk (4, sub {	707	shift->unshift_read (chunk => 4, sub {
317	# header arrived, decode	708	# header arrived, decode
318	my $len = unpack "N", $_[1];	709	my $len = unpack "N", $_[1];
319		710
320	# now read the payload	711	# now read the payload
321	shift->unshift_read_chunk ($len, sub {	712	shift->unshift_read (chunk => $len, sub {
322	my $xml = $_[1];	713	my $xml = $_[1];
323	# handle xml	714	# handle xml
324	});	715	});
325	});	716	});
326	});	717	});
327		718
328	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"
329	"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
330	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
331	pipeline sending both requests and manipulate the queue as necessary in	722	just pipeline sending both requests and manipulate the queue as necessary
332	the callbacks:	723	in the callbacks.
333		724
334	# 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"
335	$handle->push_write ("request 1\015\012");	730	$handle->push_write ("request 1\015\012");
336		731
337	# 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
338	$handle->push_read_line (sub {	733	$handle->push_read (line => sub {
339	# if we got an "OK", we have to _prepend_ another line,	734	# if we got an "OK", we have to _prepend_ another line,
340	# 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
341	# which are already in the queue when this callback is called	736	# which are already in the queue when this callback is called
342	# we don't do this in case we got an error	737	# we don't do this in case we got an error
343	if ($_[1] eq "OK") {	738	if ($_[1] eq "OK") {
344	$_[0]->unshift_read_line (sub {	739	$_[0]->unshift_read (line => sub {
345	my $response = $_[1];	740	my $response = $_[1];
346	...	741	...
347	});	742	});
348	}	743	}
349	});	744	});
350		745
351	# request two	746	# request two, simply returns 64 octets
352	$handle->push_write ("request 2\015\012");	747	$handle->push_write ("request 2\015\012");
353		748
354	# simply read 64 bytes, always	749	# simply read 64 bytes, always
355	$handle->push_read_chunk (64, sub {	750	$handle->push_read (chunk => 64, sub {
356	my $response = $_[1];	751	my $response = $_[1];
357	...	752	...
358	});	753	});
359		754
360	=over 4	755	=over 4
…		…
362	=cut	757	=cut
363		758
364	sub _drain_rbuf {	759	sub _drain_rbuf {
365	my ($self) = @_;	760	my ($self) = @_;
366		761
367	return if $self->{in_drain};
368	local $self->{in_drain} = 1;	762	local $self->{_in_drain} = 1;
369		763
		764	if (
		765	defined $self->{rbuf_max}
		766	&& $self->{rbuf_max} < length $self->{rbuf}
		767	) {
		768	$self->_error (&Errno::ENOSPC, 1), return;
		769	}
		770
		771	while () {
370	while (my $len = length $self->{rbuf}) {	772	my $len = length $self->{rbuf};
371	no strict 'refs';	773
372	if (my $cb = shift @{ $self->{queue} }) {	774	if (my $cb = shift @{ $self->{_queue} }) {
373	if (!$cb->($self)) {	775	unless ($cb->($self)) {
374	if ($self->{eof}) {	776	if ($self->{_eof}) {
375	# 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)
376	$! = &Errno::EPIPE; return $self->error;	778	$self->_error (&Errno::EPIPE, 1), return;
377	}	779	}
378		780
379	unshift @{ $self->{queue} }, $cb;	781	unshift @{ $self->{_queue} }, $cb;
380	return;	782	last;
381	}	783	}
382	} elsif ($self->{on_read}) {	784	} elsif ($self->{on_read}) {
		785	last unless $len;
		786
383	$self->{on_read}($self);	787	$self->{on_read}($self);
384		788
385	if (	789	if (
386	$self->{eof} # if no further data will arrive
387	&& $len == length $self->{rbuf} # and no data has been consumed	790	$len == length $self->{rbuf} # if no data has been consumed
388	&& !@{ $self->{queue} } # and the queue is still empty	791	&& !@{ $self->{_queue} } # and the queue is still empty
389	&& $self->{on_read} # and we still want to read data	792	&& $self->{on_read} # but we still have on_read
390	) {	793	) {
		794	# no further data will arrive
391	# then no progress can be made	795	# so no progress can be made
392	$! = &Errno::EPIPE; return $self->error;	796	$self->_error (&Errno::EPIPE, 1), return
		797	if $self->{_eof};
		798
		799	last; # more data might arrive
393	}	800	}
394	} else {	801	} else {
395	# read side becomes idle	802	# read side becomes idle
396	delete $self->{rw};	803	delete $self->{_rw} unless $self->{tls};
397	return;	804	last;
398	}	805	}
399	}	806	}
400		807
401	if ($self->{eof}) {	808	if ($self->{_eof}) {
402	$self->_shutdown;	809	if ($self->{on_eof}) {
403	$self->{on_eof}($self);	810	$self->{on_eof}($self)
		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} };
404	}	820	}
405	}	821	}
406		822
407	=item $handle->on_read ($cb)	823	=item $handle->on_read ($cb)
408		824
…		…
414		830
415	sub on_read {	831	sub on_read {
416	my ($self, $cb) = @_;	832	my ($self, $cb) = @_;
417		833
418	$self->{on_read} = $cb;	834	$self->{on_read} = $cb;
		835	$self->_drain_rbuf if $cb && !$self->{_in_drain};
419	}	836	}
420		837
421	=item $handle->rbuf	838	=item $handle->rbuf
422		839
423	Returns the read buffer (as a modifiable lvalue).	840	Returns the read buffer (as a modifiable lvalue).
…		…
442	Append the given callback to the end of the queue (C<push_read>) or	859	Append the given callback to the end of the queue (C<push_read>) or
443	prepend it (C<unshift_read>).	860	prepend it (C<unshift_read>).
444		861
445	The callback is called each time some additional read data arrives.	862	The callback is called each time some additional read data arrives.
446		863
447	It must check wether enough data is in the read buffer already.	864	It must check whether enough data is in the read buffer already.
448		865
449	If not enough data is available, it must return the empty list or a false	866	If not enough data is available, it must return the empty list or a false
450	value, in which case it will be called repeatedly until enough data is	867	value, in which case it will be called repeatedly until enough data is
451	available (or an error condition is detected).	868	available (or an error condition is detected).
452		869
…		…
454	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
455	true, it will be removed from the queue.	872	true, it will be removed from the queue.
456		873
457	=cut	874	=cut
458		875
		876	our %RH;
		877
		878	sub register_read_type($$) {
		879	$RH{$_[0]} = $_[1];
		880	}
		881
459	sub push_read {	882	sub push_read {
460	my ($self, $cb) = @_;	883	my $self = shift;
		884	my $cb = pop;
461		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
462	push @{ $self->{queue} }, $cb;	893	push @{ $self->{_queue} }, $cb;
463	$self->_drain_rbuf;	894	$self->_drain_rbuf unless $self->{_in_drain};
464	}	895	}
465		896
466	sub unshift_read {	897	sub unshift_read {
467	my ($self, $cb) = @_;	898	my $self = shift;
		899	my $cb = pop;
468		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
469	push @{ $self->{queue} }, $cb;	909	unshift @{ $self->{_queue} }, $cb;
470	$self->_drain_rbuf;	910	$self->_drain_rbuf unless $self->{_in_drain};
471	}	911	}
472		912
473	=item $handle->push_read_chunk ($len, $cb->($self, $data))	913	=item $handle->push_read (type => @args, $cb)
474		914
475	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	915	=item $handle->unshift_read (type => @args, $cb)
476		916
477	Append the given callback to the end of the queue (C<push_read_chunk>) or	917	Instead of providing a callback that parses the data itself you can chose
478	prepend it (C<unshift_read_chunk>).	918	between a number of predefined parsing formats, for chunks of data, lines
		919	etc.
479		920
480	The callback will be called only once C<$len> bytes have been read, and	921	Predefined types are (if you have ideas for additional types, feel free to
481	these C<$len> bytes will be passed to the callback.	922	drop by and tell us):
482		923
483	=cut	924	=over 4
484		925
485	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 {
486	my ($self, $len, $cb) = @_;	941	my ($self, $cb, $len) = @_;
487		942
488	sub {	943	sub {
489	$len <= length $_[0]{rbuf} or return;	944	$len <= length $_[0]{rbuf} or return;
490	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	945	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
491	1	946	1
492	}	947	}
493	}	948	};
494		949
495	sub push_read_chunk {	950	=item line => [$eol, ]$cb->($handle, $line, $eol)
496	$_[0]->push_read (&_read_chunk);
497	}
498
499
500	sub unshift_read_chunk {
501	$_[0]->unshift_read (&_read_chunk);
502	}
503
504	=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
505
506	=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
507
508	Append the given callback to the end of the queue (C<push_read_line>) or
509	prepend it (C<unshift_read_line>).
510		951
511	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
512	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
513	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
514	the end of line marker as the third argument (C<$eol>).	955	the end of line marker as the third argument (C<$eol>).
…		…
525	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
526	not marked by the end of line marker.	967	not marked by the end of line marker.
527		968
528	=cut	969	=cut
529		970
530	sub _read_line($$) {	971	register_read_type line => sub {
531	my $self = shift;	972	my ($self, $cb, $eol) = @_;
532	my $cb = pop;
533	my $eol = @_ ? shift : qr|(\015?\012)|;
534	my $pos;
535		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 {
536	$eol = qr|(\Q$eol\E)| unless ref $eol;	983	$eol = quotemeta $eol unless ref $eol;
537	$eol = qr|^(.*?)($eol)|;	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};
538		1042
539	sub {	1043	sub {
540	$_[0]{rbuf} =~ s/$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 && $$rbuf =~ $reject) {
		1053	$self->_error (&Errno::EBADMSG);
		1054	}
541		1055
542	$cb->($_[0], $1, $2);	1056	# skip
		1057	if ($skip && $$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
543	1	1097	1
544	}	1098	}
545	}	1099	};
546		1100
547	sub push_read_line {	1101	=item packstring => $format, $cb->($handle, $string)
548	$_[0]->push_read (&_read_line);
549	}
550		1102
551	sub unshift_read_line {	1103	An octet string prefixed with an encoded length. The encoding C<$format>
552	$_[0]->unshift_read (&_read_line);	1104	uses the same format as a Perl C<pack> format, but must specify a single
553	}	1105	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1106	optional C<!>, C<< < >> or C<< > >> modifier).
		1107
		1108	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.
		1109
		1110	Example: read a block of data prefixed by its length in BER-encoded
		1111	format (very efficient).
		1112
		1113	$handle->push_read (packstring => "w", sub {
		1114	my ($handle, $data) = @_;
		1115	});
		1116
		1117	=cut
		1118
		1119	register_read_type packstring => sub {
		1120	my ($self, $cb, $format) = @_;
		1121
		1122	sub {
		1123	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1124	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1125	or return;
		1126
		1127	$format = length pack $format, $len;
		1128
		1129	# bypass unshift if we already have the remaining chunk
		1130	if ($format + $len <= length $_[0]{rbuf}) {
		1131	my $data = substr $_[0]{rbuf}, $format, $len;
		1132	substr $_[0]{rbuf}, 0, $format + $len, "";
		1133	$cb->($_[0], $data);
		1134	} else {
		1135	# remove prefix
		1136	substr $_[0]{rbuf}, 0, $format, "";
		1137
		1138	# read remaining chunk
		1139	$_[0]->unshift_read (chunk => $len, $cb);
		1140	}
		1141
		1142	1
		1143	}
		1144	};
		1145
		1146	=item json => $cb->($handle, $hash_or_arrayref)
		1147
		1148	Reads a JSON object or array, decodes it and passes it to the callback.
		1149
		1150	If a C<json> object was passed to the constructor, then that will be used
		1151	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1152
		1153	This read type uses the incremental parser available with JSON version
		1154	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1155	dependency on your own: this module will load the JSON module, but
		1156	AnyEvent does not depend on it itself.
		1157
		1158	Since JSON texts are fully self-delimiting, the C<json> read and write
		1159	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1160	the C<json> write type description, above, for an actual example.
		1161
		1162	=cut
		1163
		1164	register_read_type json => sub {
		1165	my ($self, $cb) = @_;
		1166
		1167	require JSON;
		1168
		1169	my $data;
		1170	my $rbuf = \$self->{rbuf};
		1171
		1172	my $json = $self->{json} ||= JSON->new->utf8;
		1173
		1174	sub {
		1175	my $ref = $json->incr_parse ($self->{rbuf});
		1176
		1177	if ($ref) {
		1178	$self->{rbuf} = $json->incr_text;
		1179	$json->incr_text = "";
		1180	$cb->($self, $ref);
		1181
		1182	1
		1183	} else {
		1184	$self->{rbuf} = "";
		1185	()
		1186	}
		1187	}
		1188	};
		1189
		1190	=item storable => $cb->($handle, $ref)
		1191
		1192	Deserialises a L<Storable> frozen representation as written by the
		1193	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1194	data).
		1195
		1196	Raises C<EBADMSG> error if the data could not be decoded.
		1197
		1198	=cut
		1199
		1200	register_read_type storable => sub {
		1201	my ($self, $cb) = @_;
		1202
		1203	require Storable;
		1204
		1205	sub {
		1206	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1207	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1208	or return;
		1209
		1210	my $format = length pack "w", $len;
		1211
		1212	# bypass unshift if we already have the remaining chunk
		1213	if ($format + $len <= length $_[0]{rbuf}) {
		1214	my $data = substr $_[0]{rbuf}, $format, $len;
		1215	substr $_[0]{rbuf}, 0, $format + $len, "";
		1216	$cb->($_[0], Storable::thaw ($data));
		1217	} else {
		1218	# remove prefix
		1219	substr $_[0]{rbuf}, 0, $format, "";
		1220
		1221	# read remaining chunk
		1222	$_[0]->unshift_read (chunk => $len, sub {
		1223	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1224	$cb->($_[0], $ref);
		1225	} else {
		1226	$self->_error (&Errno::EBADMSG);
		1227	}
		1228	});
		1229	}
		1230
		1231	1
		1232	}
		1233	};
		1234
		1235	=back
		1236
		1237	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1238
		1239	This function (not method) lets you add your own types to C<push_read>.
		1240
		1241	Whenever the given C<type> is used, C<push_read> will invoke the code
		1242	reference with the handle object, the callback and the remaining
		1243	arguments.
		1244
		1245	The code reference is supposed to return a callback (usually a closure)
		1246	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1247
		1248	It should invoke the passed callback when it is done reading (remember to
		1249	pass C<$handle> as first argument as all other callbacks do that).
		1250
		1251	Note that this is a function, and all types registered this way will be
		1252	global, so try to use unique names.
		1253
		1254	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1255	search for C<register_read_type>)).
554		1256
555	=item $handle->stop_read	1257	=item $handle->stop_read
556		1258
557	=item $handle->start_read	1259	=item $handle->start_read
558		1260
559	In rare cases you actually do not want to read anything form the	1261	In rare cases you actually do not want to read anything from the
560	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1262	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
561	any queued callbacks will be executed then. To start readign again, call	1263	any queued callbacks will be executed then. To start reading again, call
562	C<start_read>.	1264	C<start_read>.
		1265
		1266	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1267	you change the C<on_read> callback or push/unshift a read callback, and it
		1268	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1269	there are any read requests in the queue.
		1270
		1271	These methods will have no effect when in TLS mode (as TLS doesn't support
		1272	half-duplex connections).
563		1273
564	=cut	1274	=cut
565		1275
566	sub stop_read {	1276	sub stop_read {
567	my ($self) = @_;	1277	my ($self) = @_;
568		1278
569	delete $self->{rw};	1279	delete $self->{_rw} unless $self->{tls};
570	}	1280	}
571		1281
572	sub start_read {	1282	sub start_read {
573	my ($self) = @_;	1283	my ($self) = @_;
574		1284
575	unless ($self->{rw} || $self->{eof}) {	1285	unless ($self->{_rw} || $self->{_eof}) {
576	Scalar::Util::weaken $self;	1286	Scalar::Util::weaken $self;
577		1287
578	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1288	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
		1289	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
579	my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} || 8192, length $self->{rbuf};	1290	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
580		1291
581	if ($len > 0) {	1292	if ($len > 0) {
582	if (defined $self->{rbuf_max}) {	1293	$self->{_activity} = AnyEvent->now;
583	if ($self->{rbuf_max} < length $self->{rbuf}) {	1294
584	$! = &Errno::ENOSPC; return $self->error;	1295	if ($self->{tls}) {
585	}	1296	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1297	&_dotls ($self);
		1298	} else {
		1299	$self->_drain_rbuf unless $self->{_in_drain};
586	}	1300	}
587		1301
588	} elsif (defined $len) {	1302	} elsif (defined $len) {
589	$self->{eof} = 1;
590	delete $self->{rw};	1303	delete $self->{_rw};
		1304	$self->{_eof} = 1;
		1305	$self->_drain_rbuf unless $self->{_in_drain};
591		1306
592	} elsif ($! != EAGAIN && $! != EINTR) {	1307	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
593	return $self->error;	1308	return $self->_error ($!, 1);
594	}	1309	}
595
596	$self->_drain_rbuf;
597	});	1310	});
598	}	1311	}
599	}	1312	}
600		1313
		1314	sub _dotls {
		1315	my ($self) = @_;
		1316
		1317	my $buf;
		1318
		1319	if (length $self->{_tls_wbuf}) {
		1320	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		1321	substr $self->{_tls_wbuf}, 0, $len, "";
		1322	}
		1323	}
		1324
		1325	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
		1326	unless (length $buf) {
		1327	# let's treat SSL-eof as we treat normal EOF
		1328	delete $self->{_rw};
		1329	$self->{_eof} = 1;
		1330	&_freetls;
		1331	}
		1332
		1333	$self->{rbuf} .= $buf;
		1334	$self->_drain_rbuf unless $self->{_in_drain};
		1335	$self->{tls} or return; # tls session might have gone away in callback
		1336	}
		1337
		1338	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1339
		1340	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1341	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1342	return $self->_error ($!, 1);
		1343	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1344	return $self->_error (&Errno::EIO, 1);
		1345	}
		1346
		1347	# all others are fine for our purposes
		1348	}
		1349
		1350	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1351	$self->{wbuf} .= $buf;
		1352	$self->_drain_wbuf;
		1353	}
		1354	}
		1355
		1356	=item $handle->starttls ($tls[, $tls_ctx])
		1357
		1358	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1359	object is created, you can also do that at a later time by calling
		1360	C<starttls>.
		1361
		1362	The first argument is the same as the C<tls> constructor argument (either
		1363	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1364
		1365	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1366	used when AnyEvent::Handle has to create its own TLS connection object.
		1367
		1368	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1369	call and can be used or changed to your liking. Note that the handshake
		1370	might have already started when this function returns.
		1371
		1372	If it an error to start a TLS handshake more than once per
		1373	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1374
		1375	=cut
		1376
		1377	sub starttls {
		1378	my ($self, $ssl, $ctx) = @_;
		1379
		1380	Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object"
		1381	if $self->{tls};
		1382
		1383	if ($ssl eq "accept") {
		1384	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1385	Net::SSLeay::set_accept_state ($ssl);
		1386	} elsif ($ssl eq "connect") {
		1387	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1388	Net::SSLeay::set_connect_state ($ssl);
		1389	}
		1390
		1391	$self->{tls} = $ssl;
		1392
		1393	# basically, this is deep magic (because SSL_read should have the same issues)
		1394	# but the openssl maintainers basically said: "trust us, it just works".
		1395	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1396	# and mismaintained ssleay-module doesn't even offer them).
		1397	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1398	#
		1399	# in short: this is a mess.
		1400	#
		1401	# note that we do not try to keep the length constant between writes as we are required to do.
		1402	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1403	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1404	# have identity issues in that area.
		1405	Net::SSLeay::CTX_set_mode ($self->{tls},
		1406	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1407	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1408
		1409	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1410	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1411
		1412	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1413
		1414	&_dotls; # need to trigger the initial handshake
		1415	$self->start_read; # make sure we actually do read
		1416	}
		1417
		1418	=item $handle->stoptls
		1419
		1420	Shuts down the SSL connection - this makes a proper EOF handshake by
		1421	sending a close notify to the other side, but since OpenSSL doesn't
		1422	support non-blocking shut downs, it is not possible to re-use the stream
		1423	afterwards.
		1424
		1425	=cut
		1426
		1427	sub stoptls {
		1428	my ($self) = @_;
		1429
		1430	if ($self->{tls}) {
		1431	Net::SSLeay::shutdown $self->{tls};
		1432
		1433	&_dotls;
		1434
		1435	# we don't give a shit. no, we do, but we can't. no...
		1436	# we, we... have to use openssl :/
		1437	&_freetls;
		1438	}
		1439	}
		1440
		1441	sub _freetls {
		1442	my ($self) = @_;
		1443
		1444	return unless $self->{tls};
		1445
		1446	Net::SSLeay::free (delete $self->{tls});
		1447
		1448	delete @$self{qw(_rbio _wbio _tls_wbuf)};
		1449	}
		1450
		1451	sub DESTROY {
		1452	my $self = shift;
		1453
		1454	&_freetls;
		1455
		1456	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1457
		1458	if ($linger && length $self->{wbuf}) {
		1459	my $fh = delete $self->{fh};
		1460	my $wbuf = delete $self->{wbuf};
		1461
		1462	my @linger;
		1463
		1464	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1465	my $len = syswrite $fh, $wbuf, length $wbuf;
		1466
		1467	if ($len > 0) {
		1468	substr $wbuf, 0, $len, "";
		1469	} else {
		1470	@linger = (); # end
		1471	}
		1472	});
		1473	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1474	@linger = ();
		1475	});
		1476	}
		1477	}
		1478
		1479	=item AnyEvent::Handle::TLS_CTX
		1480
		1481	This function creates and returns the Net::SSLeay::CTX object used by
		1482	default for TLS mode.
		1483
		1484	The context is created like this:
		1485
		1486	Net::SSLeay::load_error_strings;
		1487	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1488	Net::SSLeay::randomize;
		1489
		1490	my $CTX = Net::SSLeay::CTX_new;
		1491
		1492	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1493
		1494	=cut
		1495
		1496	our $TLS_CTX;
		1497
		1498	sub TLS_CTX() {
		1499	$TLS_CTX || do {
		1500	require Net::SSLeay;
		1501
		1502	Net::SSLeay::load_error_strings ();
		1503	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1504	Net::SSLeay::randomize ();
		1505
		1506	$TLS_CTX = Net::SSLeay::CTX_new ();
		1507
		1508	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1509
		1510	$TLS_CTX
		1511	}
		1512	}
		1513
601	=back	1514	=back
602		1515
		1516	=head1 SUBCLASSING AnyEvent::Handle
		1517
		1518	In many cases, you might want to subclass AnyEvent::Handle.
		1519
		1520	To make this easier, a given version of AnyEvent::Handle uses these
		1521	conventions:
		1522
		1523	=over 4
		1524
		1525	=item * all constructor arguments become object members.
		1526
		1527	At least initially, when you pass a C<tls>-argument to the constructor it
		1528	will end up in C<< $handle->{tls} >>. Those members might be changed or
		1529	mutated later on (for example C<tls> will hold the TLS connection object).
		1530
		1531	=item * other object member names are prefixed with an C<_>.
		1532
		1533	All object members not explicitly documented (internal use) are prefixed
		1534	with an underscore character, so the remaining non-C<_>-namespace is free
		1535	for use for subclasses.
		1536
		1537	=item * all members not documented here and not prefixed with an underscore
		1538	are free to use in subclasses.
		1539
		1540	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1541	member variables, but thats just life, at least it is documented.
		1542
		1543	=back
		1544
603	=head1 AUTHOR	1545	=head1 AUTHOR
604		1546
605	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	1547	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
606		1548
607	=cut	1549	=cut

Diff Legend

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