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 1.11 by root, Sun May 11 17:54:13 2008 UTC vs.
Revision 1.96 by root, Thu Oct 2 08:10:27 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	$cv->recv;
44		47
45	=head1 DESCRIPTION	48	=head1 DESCRIPTION
46		49
47	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
48	filehandles (and sockets, see L<AnyEvent::Socket> for an easy way to make	51	filehandles. For utility functions for doing non-blocking connects and accepts
49	non-blocking resolves and connects).	52	on sockets see L<AnyEvent::Util>.
		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
50		56
51	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
52	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
53	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
54		60
55	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
56	argument.	62	argument.
57		63
		64	=head2 SIGPIPE is not handled by this module
		65
		66	SIGPIPE is not handled by this module, so one of the practical
		67	requirements of using it is to ignore SIGPIPE (C<$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	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
		301	if $self->{tls};
152		302
153	$self->on_error (delete $self->{on_error}) if $self->{on_error};	303	$self->{_activity} = AnyEvent->now;
		304	$self->_timeout;
		305
154	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	306	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
155	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	307	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
156		308
157	$self->start_read;	309	$self->start_read
		310	if $self->{on_read};
158		311
159	$self	312	$self
160	}	313	}
161		314
162	sub _shutdown {	315	sub _shutdown {
163	my ($self) = @_;	316	my ($self) = @_;
164		317
		318	delete $self->{_tw};
165	delete $self->{rw};	319	delete $self->{_rw};
166	delete $self->{ww};	320	delete $self->{_ww};
167	delete $self->{fh};	321	delete $self->{fh};
168	}
169		322
		323	&_freetls;
		324
		325	delete $self->{on_read};
		326	delete $self->{_queue};
		327	}
		328
170	sub error {	329	sub _error {
171	my ($self) = @_;	330	my ($self, $errno, $fatal) = @_;
172		331
173	{
174	local $!;
175	$self->_shutdown;	332	$self->_shutdown
176	}	333	if $fatal;
		334
		335	$! = $errno;
177		336
178	if ($self->{on_error}) {	337	if ($self->{on_error}) {
179	$self->{on_error}($self);	338	$self->{on_error}($self, $fatal);
180	} else {	339	} else {
181	die "AnyEvent::Handle uncaught fatal error: $!";	340	Carp::croak "AnyEvent::Handle uncaught error: $!";
182	}	341	}
183	}	342	}
184		343
185	=item $fh = $handle->fh	344	=item $fh = $handle->fh
186		345
187	This method returns the filehandle of the L<AnyEvent::Handle> object.	346	This method returns the file handle used to create the L<AnyEvent::Handle> object.
188		347
189	=cut	348	=cut
190		349
191	sub fh { $_[0]->{fh} }	350	sub fh { $_[0]{fh} }
192		351
193	=item $handle->on_error ($cb)	352	=item $handle->on_error ($cb)
194		353
195	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	354	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
196		355
…		…
208		367
209	sub on_eof {	368	sub on_eof {
210	$_[0]{on_eof} = $_[1];	369	$_[0]{on_eof} = $_[1];
211	}	370	}
212		371
		372	=item $handle->on_timeout ($cb)
		373
		374	Replace the current C<on_timeout> callback, or disables the callback (but
		375	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
		376	argument and method.
		377
		378	=cut
		379
		380	sub on_timeout {
		381	$_[0]{on_timeout} = $_[1];
		382	}
		383
		384	=item $handle->autocork ($boolean)
		385
		386	Enables or disables the current autocork behaviour (see C<autocork>
		387	constructor argument).
		388
		389	=cut
		390
		391	=item $handle->no_delay ($boolean)
		392
		393	Enables or disables the C<no_delay> setting (see constructor argument of
		394	the same name for details).
		395
		396	=cut
		397
		398	sub no_delay {
		399	$_[0]{no_delay} = $_[1];
		400
		401	eval {
		402	local $SIG{__DIE__};
		403	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		404	};
		405	}
		406
		407	#############################################################################
		408
		409	=item $handle->timeout ($seconds)
		410
		411	Configures (or disables) the inactivity timeout.
		412
		413	=cut
		414
		415	sub timeout {
		416	my ($self, $timeout) = @_;
		417
		418	$self->{timeout} = $timeout;
		419	$self->_timeout;
		420	}
		421
		422	# reset the timeout watcher, as neccessary
		423	# also check for time-outs
		424	sub _timeout {
		425	my ($self) = @_;
		426
		427	if ($self->{timeout}) {
		428	my $NOW = AnyEvent->now;
		429
		430	# when would the timeout trigger?
		431	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		432
		433	# now or in the past already?
		434	if ($after <= 0) {
		435	$self->{_activity} = $NOW;
		436
		437	if ($self->{on_timeout}) {
		438	$self->{on_timeout}($self);
		439	} else {
		440	$self->_error (&Errno::ETIMEDOUT);
		441	}
		442
		443	# callback could have changed timeout value, optimise
		444	return unless $self->{timeout};
		445
		446	# calculate new after
		447	$after = $self->{timeout};
		448	}
		449
		450	Scalar::Util::weaken $self;
		451	return unless $self; # ->error could have destroyed $self
		452
		453	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		454	delete $self->{_tw};
		455	$self->_timeout;
		456	});
		457	} else {
		458	delete $self->{_tw};
		459	}
		460	}
		461
213	#############################################################################	462	#############################################################################
214		463
215	=back	464	=back
216		465
217	=head2 WRITE QUEUE	466	=head2 WRITE QUEUE
…		…
220	for reading.	469	for reading.
221		470
222	The write queue is very simple: you can add data to its end, and	471	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.	472	AnyEvent::Handle will automatically try to get rid of it for you.
224		473
225	When data could be writtena nd the write buffer is shorter then the low	474	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.	475	water mark, the C<on_drain> callback will be invoked.
227		476
228	=over 4	477	=over 4
229		478
230	=item $handle->on_drain ($cb)	479	=item $handle->on_drain ($cb)
…		…
238	my ($self, $cb) = @_;	487	my ($self, $cb) = @_;
239		488
240	$self->{on_drain} = $cb;	489	$self->{on_drain} = $cb;
241		490
242	$cb->($self)	491	$cb->($self)
243	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	492	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
244	}	493	}
245		494
246	=item $handle->push_write ($data)	495	=item $handle->push_write ($data)
247		496
248	Queues the given scalar to be written. You can push as much data as you	497	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>	498	want (only limited by the available memory), as C<AnyEvent::Handle>
250	buffers it independently of the kernel.	499	buffers it independently of the kernel.
251		500
252	=cut	501	=cut
253		502
254	sub push_write {	503	sub _drain_wbuf {
255	my ($self, $data) = @_;	504	my ($self) = @_;
256		505
257	$self->{wbuf} .= $data;	506	if (!$self->{_ww} && length $self->{wbuf}) {
258		507
259	unless ($self->{ww}) {
260	Scalar::Util::weaken $self;	508	Scalar::Util::weaken $self;
		509
261	my $cb = sub {	510	my $cb = sub {
262	my $len = syswrite $self->{fh}, $self->{wbuf};	511	my $len = syswrite $self->{fh}, $self->{wbuf};
263		512
264	if ($len > 0) {	513	if ($len >= 0) {
265	substr $self->{wbuf}, 0, $len, "";	514	substr $self->{wbuf}, 0, $len, "";
266		515
		516	$self->{_activity} = AnyEvent->now;
267		517
268	$self->{on_drain}($self)	518	$self->{on_drain}($self)
269	if $self->{low_water_mark} >= length $self->{wbuf}	519	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
270	&& $self->{on_drain};	520	&& $self->{on_drain};
271		521
272	delete $self->{ww} unless length $self->{wbuf};	522	delete $self->{_ww} unless length $self->{wbuf};
273	} elsif ($! != EAGAIN && $! != EINTR) {	523	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
274	$self->error;	524	$self->_error ($!, 1);
275	}	525	}
276	};	526	};
277		527
		528	# try to write data immediately
		529	$cb->() unless $self->{autocork};
		530
		531	# if still data left in wbuf, we need to poll
278	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	532	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
279		533	if length $self->{wbuf};
280	$cb->($self);
281	};	534	};
282	}	535	}
		536
		537	our %WH;
		538
		539	sub register_write_type($$) {
		540	$WH{$_[0]} = $_[1];
		541	}
		542
		543	sub push_write {
		544	my $self = shift;
		545
		546	if (@_ > 1) {
		547	my $type = shift;
		548
		549	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		550	->($self, @_);
		551	}
		552
		553	if ($self->{tls}) {
		554	$self->{_tls_wbuf} .= $_[0];
		555	&_dotls ($self);
		556	} else {
		557	$self->{wbuf} .= $_[0];
		558	$self->_drain_wbuf;
		559	}
		560	}
		561
		562	=item $handle->push_write (type => @args)
		563
		564	Instead of formatting your data yourself, you can also let this module do
		565	the job by specifying a type and type-specific arguments.
		566
		567	Predefined types are (if you have ideas for additional types, feel free to
		568	drop by and tell us):
		569
		570	=over 4
		571
		572	=item netstring => $string
		573
		574	Formats the given value as netstring
		575	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		576
		577	=cut
		578
		579	register_write_type netstring => sub {
		580	my ($self, $string) = @_;
		581
		582	(length $string) . ":$string,"
		583	};
		584
		585	=item packstring => $format, $data
		586
		587	An octet string prefixed with an encoded length. The encoding C<$format>
		588	uses the same format as a Perl C<pack> format, but must specify a single
		589	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		590	optional C<!>, C<< < >> or C<< > >> modifier).
		591
		592	=cut
		593
		594	register_write_type packstring => sub {
		595	my ($self, $format, $string) = @_;
		596
		597	pack "$format/a*", $string
		598	};
		599
		600	=item json => $array_or_hashref
		601
		602	Encodes the given hash or array reference into a JSON object. Unless you
		603	provide your own JSON object, this means it will be encoded to JSON text
		604	in UTF-8.
		605
		606	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		607	one end of a handle and read them at the other end without using any
		608	additional framing.
		609
		610	The generated JSON text is guaranteed not to contain any newlines: While
		611	this module doesn't need delimiters after or between JSON texts to be
		612	able to read them, many other languages depend on that.
		613
		614	A simple RPC protocol that interoperates easily with others is to send
		615	JSON arrays (or objects, although arrays are usually the better choice as
		616	they mimic how function argument passing works) and a newline after each
		617	JSON text:
		618
		619	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		620	$handle->push_write ("\012");
		621
		622	An AnyEvent::Handle receiver would simply use the C<json> read type and
		623	rely on the fact that the newline will be skipped as leading whitespace:
		624
		625	$handle->push_read (json => sub { my $array = $_[1]; ... });
		626
		627	Other languages could read single lines terminated by a newline and pass
		628	this line into their JSON decoder of choice.
		629
		630	=cut
		631
		632	register_write_type json => sub {
		633	my ($self, $ref) = @_;
		634
		635	require JSON;
		636
		637	$self->{json} ? $self->{json}->encode ($ref)
		638	: JSON::encode_json ($ref)
		639	};
		640
		641	=item storable => $reference
		642
		643	Freezes the given reference using L<Storable> and writes it to the
		644	handle. Uses the C<nfreeze> format.
		645
		646	=cut
		647
		648	register_write_type storable => sub {
		649	my ($self, $ref) = @_;
		650
		651	require Storable;
		652
		653	pack "w/a*", Storable::nfreeze ($ref)
		654	};
		655
		656	=back
		657
		658	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		659
		660	This function (not method) lets you add your own types to C<push_write>.
		661	Whenever the given C<type> is used, C<push_write> will invoke the code
		662	reference with the handle object and the remaining arguments.
		663
		664	The code reference is supposed to return a single octet string that will
		665	be appended to the write buffer.
		666
		667	Note that this is a function, and all types registered this way will be
		668	global, so try to use unique names.
		669
		670	=cut
283		671
284	#############################################################################	672	#############################################################################
285		673
286	=back	674	=back
287		675
…		…
294	ways, the "simple" way, using only C<on_read> and the "complex" way, using	682	ways, the "simple" way, using only C<on_read> and the "complex" way, using
295	a queue.	683	a queue.
296		684
297	In the simple case, you just install an C<on_read> callback and whenever	685	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	686	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	687	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
300	or not.	688	leave the data there if you want to accumulate more (e.g. when only a
		689	partial message has been received so far).
301		690
302	In the more complex case, you want to queue multiple callbacks. In this	691	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	692	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>,	693	data arrives (also the first time it is queued) and removes it when it has
305	below).	694	done its job (see C<push_read>, below).
306		695
307	This way you can, for example, push three line-reads, followed by reading	696	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.	697	a chunk of data, and AnyEvent::Handle will execute them in order.
309		698
310	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	699	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
311	the specified number of bytes which give an XML datagram.	700	the specified number of bytes which give an XML datagram.
312		701
313	# in the default state, expect some header bytes	702	# in the default state, expect some header bytes
314	$handle->on_read (sub {	703	$handle->on_read (sub {
315	# some data is here, now queue the length-header-read (4 octets)	704	# some data is here, now queue the length-header-read (4 octets)
316	shift->unshift_read_chunk (4, sub {	705	shift->unshift_read (chunk => 4, sub {
317	# header arrived, decode	706	# header arrived, decode
318	my $len = unpack "N", $_[1];	707	my $len = unpack "N", $_[1];
319		708
320	# now read the payload	709	# now read the payload
321	shift->unshift_read_chunk ($len, sub {	710	shift->unshift_read (chunk => $len, sub {
322	my $xml = $_[1];	711	my $xml = $_[1];
323	# handle xml	712	# handle xml
324	});	713	});
325	});	714	});
326	});	715	});
327		716
328	Example 2: Implement a client for a protocol that replies either with	717	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	718	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	719	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	720	just pipeline sending both requests and manipulate the queue as necessary
332	the callbacks:	721	in the callbacks.
333		722
334	# request one	723	When the first callback is called and sees an "OK" response, it will
		724	C<unshift> another line-read. This line-read will be queued I<before> the
		725	64-byte chunk callback.
		726
		727	# request one, returns either "OK + extra line" or "ERROR"
335	$handle->push_write ("request 1\015\012");	728	$handle->push_write ("request 1\015\012");
336		729
337	# we expect "ERROR" or "OK" as response, so push a line read	730	# we expect "ERROR" or "OK" as response, so push a line read
338	$handle->push_read_line (sub {	731	$handle->push_read (line => sub {
339	# if we got an "OK", we have to _prepend_ another line,	732	# 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	733	# 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	734	# which are already in the queue when this callback is called
342	# we don't do this in case we got an error	735	# we don't do this in case we got an error
343	if ($_[1] eq "OK") {	736	if ($_[1] eq "OK") {
344	$_[0]->unshift_read_line (sub {	737	$_[0]->unshift_read (line => sub {
345	my $response = $_[1];	738	my $response = $_[1];
346	...	739	...
347	});	740	});
348	}	741	}
349	});	742	});
350		743
351	# request two	744	# request two, simply returns 64 octets
352	$handle->push_write ("request 2\015\012");	745	$handle->push_write ("request 2\015\012");
353		746
354	# simply read 64 bytes, always	747	# simply read 64 bytes, always
355	$handle->push_read_chunk (64, sub {	748	$handle->push_read (chunk => 64, sub {
356	my $response = $_[1];	749	my $response = $_[1];
357	...	750	...
358	});	751	});
359		752
360	=over 4	753	=over 4
…		…
362	=cut	755	=cut
363		756
364	sub _drain_rbuf {	757	sub _drain_rbuf {
365	my ($self) = @_;	758	my ($self) = @_;
366		759
367	return if $self->{in_drain};
368	local $self->{in_drain} = 1;	760	local $self->{_in_drain} = 1;
369		761
		762	if (
		763	defined $self->{rbuf_max}
		764	&& $self->{rbuf_max} < length $self->{rbuf}
		765	) {
		766	$self->_error (&Errno::ENOSPC, 1), return;
		767	}
		768
		769	while () {
370	while (my $len = length $self->{rbuf}) {	770	my $len = length $self->{rbuf};
371	no strict 'refs';	771
372	if (my $cb = shift @{ $self->{queue} }) {	772	if (my $cb = shift @{ $self->{_queue} }) {
373	if (!$cb->($self)) {	773	unless ($cb->($self)) {
374	if ($self->{eof}) {	774	if ($self->{_eof}) {
375	# no progress can be made (not enough data and no data forthcoming)	775	# no progress can be made (not enough data and no data forthcoming)
376	$! = &Errno::EPIPE; return $self->error;	776	$self->_error (&Errno::EPIPE, 1), return;
377	}	777	}
378		778
379	unshift @{ $self->{queue} }, $cb;	779	unshift @{ $self->{_queue} }, $cb;
380	return;	780	last;
381	}	781	}
382	} elsif ($self->{on_read}) {	782	} elsif ($self->{on_read}) {
		783	last unless $len;
		784
383	$self->{on_read}($self);	785	$self->{on_read}($self);
384		786
385	if (	787	if (
386	$self->{eof} # if no further data will arrive
387	&& $len == length $self->{rbuf} # and no data has been consumed	788	$len == length $self->{rbuf} # if no data has been consumed
388	&& !@{ $self->{queue} } # and the queue is still empty	789	&& !@{ $self->{_queue} } # and the queue is still empty
389	&& $self->{on_read} # and we still want to read data	790	&& $self->{on_read} # but we still have on_read
390	) {	791	) {
		792	# no further data will arrive
391	# then no progress can be made	793	# so no progress can be made
392	$! = &Errno::EPIPE; return $self->error;	794	$self->_error (&Errno::EPIPE, 1), return
		795	if $self->{_eof};
		796
		797	last; # more data might arrive
393	}	798	}
394	} else {	799	} else {
395	# read side becomes idle	800	# read side becomes idle
396	delete $self->{rw};	801	delete $self->{_rw} unless $self->{tls};
397	return;	802	last;
398	}	803	}
399	}	804	}
400		805
401	if ($self->{eof}) {	806	if ($self->{_eof}) {
402	$self->_shutdown;	807	if ($self->{on_eof}) {
403	$self->{on_eof}($self);	808	$self->{on_eof}($self)
		809	} else {
		810	$self->_error (0, 1);
		811	}
		812	}
		813
		814	# may need to restart read watcher
		815	unless ($self->{_rw}) {
		816	$self->start_read
		817	if $self->{on_read} || @{ $self->{_queue} };
404	}	818	}
405	}	819	}
406		820
407	=item $handle->on_read ($cb)	821	=item $handle->on_read ($cb)
408		822
…		…
414		828
415	sub on_read {	829	sub on_read {
416	my ($self, $cb) = @_;	830	my ($self, $cb) = @_;
417		831
418	$self->{on_read} = $cb;	832	$self->{on_read} = $cb;
		833	$self->_drain_rbuf if $cb && !$self->{_in_drain};
419	}	834	}
420		835
421	=item $handle->rbuf	836	=item $handle->rbuf
422		837
423	Returns the read buffer (as a modifiable lvalue).	838	Returns the read buffer (as a modifiable lvalue).
…		…
442	Append the given callback to the end of the queue (C<push_read>) or	857	Append the given callback to the end of the queue (C<push_read>) or
443	prepend it (C<unshift_read>).	858	prepend it (C<unshift_read>).
444		859
445	The callback is called each time some additional read data arrives.	860	The callback is called each time some additional read data arrives.
446		861
447	It must check wether enough data is in the read buffer already.	862	It must check whether enough data is in the read buffer already.
448		863
449	If not enough data is available, it must return the empty list or a false	864	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	865	value, in which case it will be called repeatedly until enough data is
451	available (or an error condition is detected).	866	available (or an error condition is detected).
452		867
…		…
454	interested in (which can be none at all) and return a true value. After returning	869	interested in (which can be none at all) and return a true value. After returning
455	true, it will be removed from the queue.	870	true, it will be removed from the queue.
456		871
457	=cut	872	=cut
458		873
		874	our %RH;
		875
		876	sub register_read_type($$) {
		877	$RH{$_[0]} = $_[1];
		878	}
		879
459	sub push_read {	880	sub push_read {
460	my ($self, $cb) = @_;	881	my $self = shift;
		882	my $cb = pop;
461		883
		884	if (@_) {
		885	my $type = shift;
		886
		887	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		888	->($self, $cb, @_);
		889	}
		890
462	push @{ $self->{queue} }, $cb;	891	push @{ $self->{_queue} }, $cb;
463	$self->_drain_rbuf;	892	$self->_drain_rbuf unless $self->{_in_drain};
464	}	893	}
465		894
466	sub unshift_read {	895	sub unshift_read {
467	my ($self, $cb) = @_;	896	my $self = shift;
		897	my $cb = pop;
468		898
		899	if (@_) {
		900	my $type = shift;
		901
		902	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		903	->($self, $cb, @_);
		904	}
		905
		906
469	push @{ $self->{queue} }, $cb;	907	unshift @{ $self->{_queue} }, $cb;
470	$self->_drain_rbuf;	908	$self->_drain_rbuf unless $self->{_in_drain};
471	}	909	}
472		910
473	=item $handle->push_read_chunk ($len, $cb->($self, $data))	911	=item $handle->push_read (type => @args, $cb)
474		912
475	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	913	=item $handle->unshift_read (type => @args, $cb)
476		914
477	Append the given callback to the end of the queue (C<push_read_chunk>) or	915	Instead of providing a callback that parses the data itself you can chose
478	prepend it (C<unshift_read_chunk>).	916	between a number of predefined parsing formats, for chunks of data, lines
		917	etc.
479		918
480	The callback will be called only once C<$len> bytes have been read, and	919	Predefined types are (if you have ideas for additional types, feel free to
481	these C<$len> bytes will be passed to the callback.	920	drop by and tell us):
482		921
483	=cut	922	=over 4
484		923
485	sub _read_chunk($$) {	924	=item chunk => $octets, $cb->($handle, $data)
		925
		926	Invoke the callback only once C<$octets> bytes have been read. Pass the
		927	data read to the callback. The callback will never be called with less
		928	data.
		929
		930	Example: read 2 bytes.
		931
		932	$handle->push_read (chunk => 2, sub {
		933	warn "yay ", unpack "H*", $_[1];
		934	});
		935
		936	=cut
		937
		938	register_read_type chunk => sub {
486	my ($self, $len, $cb) = @_;	939	my ($self, $cb, $len) = @_;
487		940
488	sub {	941	sub {
489	$len <= length $_[0]{rbuf} or return;	942	$len <= length $_[0]{rbuf} or return;
490	$cb->($self, $_[0], substr $_[0]{rbuf}, 0, $len, "");	943	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
491	1	944	1
492	}	945	}
493	}	946	};
494		947
495	sub push_read_chunk {	948	=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		949
511	The callback will be called only once a full line (including the end of	950	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	951	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	952	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>).	953	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	964	Partial lines at the end of the stream will never be returned, as they are
526	not marked by the end of line marker.	965	not marked by the end of line marker.
527		966
528	=cut	967	=cut
529		968
530	sub _read_line($$) {	969	register_read_type line => sub {
531	my $self = shift;	970	my ($self, $cb, $eol) = @_;
532	my $cb = pop;
533	my $eol = @_ ? shift : qr|(\015?\012)|;
534	my $pos;
535		971
		972	if (@_ < 3) {
		973	# this is more than twice as fast as the generic code below
		974	sub {
		975	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		976
		977	$cb->($_[0], $1, $2);
		978	1
		979	}
		980	} else {
536	$eol = qr|(\Q$eol\E)| unless ref $eol;	981	$eol = quotemeta $eol unless ref $eol;
537	$eol = qr|^(.*?)($eol)|;	982	$eol = qr|^(.*?)($eol)|s;
		983
		984	sub {
		985	$_[0]{rbuf} =~ s/$eol// or return;
		986
		987	$cb->($_[0], $1, $2);
		988	1
		989	}
		990	}
		991	};
		992
		993	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		994
		995	Makes a regex match against the regex object C<$accept> and returns
		996	everything up to and including the match.
		997
		998	Example: read a single line terminated by '\n'.
		999
		1000	$handle->push_read (regex => qr<\n>, sub { ... });
		1001
		1002	If C<$reject> is given and not undef, then it determines when the data is
		1003	to be rejected: it is matched against the data when the C<$accept> regex
		1004	does not match and generates an C<EBADMSG> error when it matches. This is
		1005	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		1006	receive buffer overflow).
		1007
		1008	Example: expect a single decimal number followed by whitespace, reject
		1009	anything else (not the use of an anchor).
		1010
		1011	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		1012
		1013	If C<$skip> is given and not C<undef>, then it will be matched against
		1014	the receive buffer when neither C<$accept> nor C<$reject> match,
		1015	and everything preceding and including the match will be accepted
		1016	unconditionally. This is useful to skip large amounts of data that you
		1017	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		1018	have to start matching from the beginning. This is purely an optimisation
		1019	and is usually worth only when you expect more than a few kilobytes.
		1020
		1021	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		1022	expect the header to be very large (it isn't in practise, but...), we use
		1023	a skip regex to skip initial portions. The skip regex is tricky in that
		1024	it only accepts something not ending in either \015 or \012, as these are
		1025	required for the accept regex.
		1026
		1027	$handle->push_read (regex =>
		1028	qr<\015\012\015\012>,
		1029	undef, # no reject
		1030	qr<^.*[^\015\012]>,
		1031	sub { ... });
		1032
		1033	=cut
		1034
		1035	register_read_type regex => sub {
		1036	my ($self, $cb, $accept, $reject, $skip) = @_;
		1037
		1038	my $data;
		1039	my $rbuf = \$self->{rbuf};
538		1040
539	sub {	1041	sub {
540	$_[0]{rbuf} =~ s/$eol// or return;	1042	# accept
541		1043	if ($$rbuf =~ $accept) {
		1044	$data .= substr $$rbuf, 0, $+[0], "";
542	$cb->($self, $1, $2);	1045	$cb->($self, $data);
		1046	return 1;
		1047	}
		1048
		1049	# reject
		1050	if ($reject && $$rbuf =~ $reject) {
		1051	$self->_error (&Errno::EBADMSG);
		1052	}
		1053
		1054	# skip
		1055	if ($skip && $$rbuf =~ $skip) {
		1056	$data .= substr $$rbuf, 0, $+[0], "";
		1057	}
		1058
		1059	()
		1060	}
		1061	};
		1062
		1063	=item netstring => $cb->($handle, $string)
		1064
		1065	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1066
		1067	Throws an error with C<$!> set to EBADMSG on format violations.
		1068
		1069	=cut
		1070
		1071	register_read_type netstring => sub {
		1072	my ($self, $cb) = @_;
		1073
		1074	sub {
		1075	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1076	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1077	$self->_error (&Errno::EBADMSG);
		1078	}
		1079	return;
		1080	}
		1081
		1082	my $len = $1;
		1083
		1084	$self->unshift_read (chunk => $len, sub {
		1085	my $string = $_[1];
		1086	$_[0]->unshift_read (chunk => 1, sub {
		1087	if ($_[1] eq ",") {
		1088	$cb->($_[0], $string);
		1089	} else {
		1090	$self->_error (&Errno::EBADMSG);
		1091	}
		1092	});
		1093	});
		1094
543	1	1095	1
544	}	1096	}
545	}	1097	};
546		1098
547	sub push_read_line {	1099	=item packstring => $format, $cb->($handle, $string)
548	$_[0]->push_read (&_read_line);
549	}
550		1100
551	sub unshift_read_line {	1101	An octet string prefixed with an encoded length. The encoding C<$format>
552	$_[0]->unshift_read (&_read_line);	1102	uses the same format as a Perl C<pack> format, but must specify a single
553	}	1103	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1104	optional C<!>, C<< < >> or C<< > >> modifier).
		1105
		1106	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1107	EPP uses a prefix of C<N> (4 octtes).
		1108
		1109	Example: read a block of data prefixed by its length in BER-encoded
		1110	format (very efficient).
		1111
		1112	$handle->push_read (packstring => "w", sub {
		1113	my ($handle, $data) = @_;
		1114	});
		1115
		1116	=cut
		1117
		1118	register_read_type packstring => sub {
		1119	my ($self, $cb, $format) = @_;
		1120
		1121	sub {
		1122	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1123	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1124	or return;
		1125
		1126	$format = length pack $format, $len;
		1127
		1128	# bypass unshift if we already have the remaining chunk
		1129	if ($format + $len <= length $_[0]{rbuf}) {
		1130	my $data = substr $_[0]{rbuf}, $format, $len;
		1131	substr $_[0]{rbuf}, 0, $format + $len, "";
		1132	$cb->($_[0], $data);
		1133	} else {
		1134	# remove prefix
		1135	substr $_[0]{rbuf}, 0, $format, "";
		1136
		1137	# read remaining chunk
		1138	$_[0]->unshift_read (chunk => $len, $cb);
		1139	}
		1140
		1141	1
		1142	}
		1143	};
		1144
		1145	=item json => $cb->($handle, $hash_or_arrayref)
		1146
		1147	Reads a JSON object or array, decodes it and passes it to the callback.
		1148
		1149	If a C<json> object was passed to the constructor, then that will be used
		1150	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1151
		1152	This read type uses the incremental parser available with JSON version
		1153	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1154	dependency on your own: this module will load the JSON module, but
		1155	AnyEvent does not depend on it itself.
		1156
		1157	Since JSON texts are fully self-delimiting, the C<json> read and write
		1158	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1159	the C<json> write type description, above, for an actual example.
		1160
		1161	=cut
		1162
		1163	register_read_type json => sub {
		1164	my ($self, $cb) = @_;
		1165
		1166	require JSON;
		1167
		1168	my $data;
		1169	my $rbuf = \$self->{rbuf};
		1170
		1171	my $json = $self->{json} ||= JSON->new->utf8;
		1172
		1173	sub {
		1174	my $ref = $json->incr_parse ($self->{rbuf});
		1175
		1176	if ($ref) {
		1177	$self->{rbuf} = $json->incr_text;
		1178	$json->incr_text = "";
		1179	$cb->($self, $ref);
		1180
		1181	1
		1182	} else {
		1183	$self->{rbuf} = "";
		1184	()
		1185	}
		1186	}
		1187	};
		1188
		1189	=item storable => $cb->($handle, $ref)
		1190
		1191	Deserialises a L<Storable> frozen representation as written by the
		1192	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1193	data).
		1194
		1195	Raises C<EBADMSG> error if the data could not be decoded.
		1196
		1197	=cut
		1198
		1199	register_read_type storable => sub {
		1200	my ($self, $cb) = @_;
		1201
		1202	require Storable;
		1203
		1204	sub {
		1205	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1206	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1207	or return;
		1208
		1209	my $format = length pack "w", $len;
		1210
		1211	# bypass unshift if we already have the remaining chunk
		1212	if ($format + $len <= length $_[0]{rbuf}) {
		1213	my $data = substr $_[0]{rbuf}, $format, $len;
		1214	substr $_[0]{rbuf}, 0, $format + $len, "";
		1215	$cb->($_[0], Storable::thaw ($data));
		1216	} else {
		1217	# remove prefix
		1218	substr $_[0]{rbuf}, 0, $format, "";
		1219
		1220	# read remaining chunk
		1221	$_[0]->unshift_read (chunk => $len, sub {
		1222	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1223	$cb->($_[0], $ref);
		1224	} else {
		1225	$self->_error (&Errno::EBADMSG);
		1226	}
		1227	});
		1228	}
		1229
		1230	1
		1231	}
		1232	};
		1233
		1234	=back
		1235
		1236	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		1237
		1238	This function (not method) lets you add your own types to C<push_read>.
		1239
		1240	Whenever the given C<type> is used, C<push_read> will invoke the code
		1241	reference with the handle object, the callback and the remaining
		1242	arguments.
		1243
		1244	The code reference is supposed to return a callback (usually a closure)
		1245	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		1246
		1247	It should invoke the passed callback when it is done reading (remember to
		1248	pass C<$handle> as first argument as all other callbacks do that).
		1249
		1250	Note that this is a function, and all types registered this way will be
		1251	global, so try to use unique names.
		1252
		1253	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		1254	search for C<register_read_type>)).
554		1255
555	=item $handle->stop_read	1256	=item $handle->stop_read
556		1257
557	=item $handle->start_read	1258	=item $handle->start_read
558		1259
559	In rare cases you actually do not want to read anything form the	1260	In rare cases you actually do not want to read anything from the
560	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1261	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
561	any queued callbacks will be executed then. To start readign again, call	1262	any queued callbacks will be executed then. To start reading again, call
562	C<start_read>.	1263	C<start_read>.
		1264
		1265	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1266	you change the C<on_read> callback or push/unshift a read callback, and it
		1267	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1268	there are any read requests in the queue.
		1269
		1270	These methods will have no effect when in TLS mode (as TLS doesn't support
		1271	half-duplex connections).
563		1272
564	=cut	1273	=cut
565		1274
566	sub stop_read {	1275	sub stop_read {
567	my ($self) = @_;	1276	my ($self) = @_;
568		1277
569	delete $self->{rw};	1278	delete $self->{_rw} unless $self->{tls};
570	}	1279	}
571		1280
572	sub start_read {	1281	sub start_read {
573	my ($self) = @_;	1282	my ($self) = @_;
574		1283
575	unless ($self->{rw} || $self->{eof}) {	1284	unless ($self->{_rw} || $self->{_eof}) {
576	Scalar::Util::weaken $self;	1285	Scalar::Util::weaken $self;
577		1286
578	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1287	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
		1288	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
579	my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} || 8192, length $self->{rbuf};	1289	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
580		1290
581	if ($len > 0) {	1291	if ($len > 0) {
582	if (defined $self->{rbuf_max}) {	1292	$self->{_activity} = AnyEvent->now;
583	if ($self->{rbuf_max} < length $self->{rbuf}) {	1293
584	$! = &Errno::ENOSPC; return $self->error;	1294	if ($self->{tls}) {
585	}	1295	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1296	&_dotls ($self);
		1297	} else {
		1298	$self->_drain_rbuf unless $self->{_in_drain};
586	}	1299	}
587		1300
588	} elsif (defined $len) {	1301	} elsif (defined $len) {
589	$self->{eof} = 1;
590	delete $self->{rw};	1302	delete $self->{_rw};
		1303	$self->{_eof} = 1;
		1304	$self->_drain_rbuf unless $self->{_in_drain};
591		1305
592	} elsif ($! != EAGAIN && $! != EINTR) {	1306	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
593	return $self->error;	1307	return $self->_error ($!, 1);
594	}	1308	}
595
596	$self->_drain_rbuf;
597	});	1309	});
598	}	1310	}
599	}	1311	}
600		1312
		1313	sub _dotls {
		1314	my ($self) = @_;
		1315
		1316	my $buf;
		1317
		1318	if (length $self->{_tls_wbuf}) {
		1319	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		1320	substr $self->{_tls_wbuf}, 0, $len, "";
		1321	}
		1322	}
		1323
		1324	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
		1325	unless (length $buf) {
		1326	# let's treat SSL-eof as we treat normal EOF
		1327	delete $self->{_rw};
		1328	$self->{_eof} = 1;
		1329	&_freetls;
		1330	}
		1331
		1332	$self->{rbuf} .= $buf;
		1333	$self->_drain_rbuf unless $self->{_in_drain};
		1334	$self->{tls} or return; # tls session might have gone away in callback
		1335	}
		1336
		1337	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1338
		1339	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1340	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1341	return $self->_error ($!, 1);
		1342	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1343	return $self->_error (&Errno::EIO, 1);
		1344	}
		1345
		1346	# all others are fine for our purposes
		1347	}
		1348
		1349	while (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1350	$self->{wbuf} .= $buf;
		1351	$self->_drain_wbuf;
		1352	}
		1353	}
		1354
		1355	=item $handle->starttls ($tls[, $tls_ctx])
		1356
		1357	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1358	object is created, you can also do that at a later time by calling
		1359	C<starttls>.
		1360
		1361	The first argument is the same as the C<tls> constructor argument (either
		1362	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1363
		1364	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1365	used when AnyEvent::Handle has to create its own TLS connection object.
		1366
		1367	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1368	call and can be used or changed to your liking. Note that the handshake
		1369	might have already started when this function returns.
		1370
		1371	If it an error to start a TLS handshake more than once per
		1372	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1373
		1374	=cut
		1375
		1376	sub starttls {
		1377	my ($self, $ssl, $ctx) = @_;
		1378
		1379	require Net::SSLeay;
		1380
		1381	Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object"
		1382	if $self->{tls};
		1383
		1384	if ($ssl eq "accept") {
		1385	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1386	Net::SSLeay::set_accept_state ($ssl);
		1387	} elsif ($ssl eq "connect") {
		1388	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
		1389	Net::SSLeay::set_connect_state ($ssl);
		1390	}
		1391
		1392	$self->{tls} = $ssl;
		1393
		1394	# basically, this is deep magic (because SSL_read should have the same issues)
		1395	# but the openssl maintainers basically said: "trust us, it just works".
		1396	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1397	# and mismaintained ssleay-module doesn't even offer them).
		1398	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1399	#
		1400	# in short: this is a mess.
		1401	#
		1402	# note that we do not try to keep the length constant between writes as we are required to do.
		1403	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1404	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1405	# have identity issues in that area.
		1406	Net::SSLeay::CTX_set_mode ($self->{tls},
		1407	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
		1408	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
		1409
		1410	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1411	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1412
		1413	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1414
		1415	&_dotls; # need to trigger the initial handshake
		1416	$self->start_read; # make sure we actually do read
		1417	}
		1418
		1419	=item $handle->stoptls
		1420
		1421	Shuts down the SSL connection - this makes a proper EOF handshake by
		1422	sending a close notify to the other side, but since OpenSSL doesn't
		1423	support non-blocking shut downs, it is not possible to re-use the stream
		1424	afterwards.
		1425
		1426	=cut
		1427
		1428	sub stoptls {
		1429	my ($self) = @_;
		1430
		1431	if ($self->{tls}) {
		1432	Net::SSLeay::shutdown ($self->{tls});
		1433
		1434	&_dotls;
		1435
		1436	# we don't give a shit. no, we do, but we can't. no...
		1437	# we, we... have to use openssl :/
		1438	&_freetls;
		1439	}
		1440	}
		1441
		1442	sub _freetls {
		1443	my ($self) = @_;
		1444
		1445	return unless $self->{tls};
		1446
		1447	Net::SSLeay::free (delete $self->{tls});
		1448
		1449	delete @$self{qw(_rbio _wbio _tls_wbuf)};
		1450	}
		1451
		1452	sub DESTROY {
		1453	my $self = shift;
		1454
		1455	&_freetls;
		1456
		1457	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1458
		1459	if ($linger && length $self->{wbuf}) {
		1460	my $fh = delete $self->{fh};
		1461	my $wbuf = delete $self->{wbuf};
		1462
		1463	my @linger;
		1464
		1465	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1466	my $len = syswrite $fh, $wbuf, length $wbuf;
		1467
		1468	if ($len > 0) {
		1469	substr $wbuf, 0, $len, "";
		1470	} else {
		1471	@linger = (); # end
		1472	}
		1473	});
		1474	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1475	@linger = ();
		1476	});
		1477	}
		1478	}
		1479
		1480	=item AnyEvent::Handle::TLS_CTX
		1481
		1482	This function creates and returns the Net::SSLeay::CTX object used by
		1483	default for TLS mode.
		1484
		1485	The context is created like this:
		1486
		1487	Net::SSLeay::load_error_strings;
		1488	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1489	Net::SSLeay::randomize;
		1490
		1491	my $CTX = Net::SSLeay::CTX_new;
		1492
		1493	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1494
		1495	=cut
		1496
		1497	our $TLS_CTX;
		1498
		1499	sub TLS_CTX() {
		1500	$TLS_CTX || do {
		1501	require Net::SSLeay;
		1502
		1503	Net::SSLeay::load_error_strings ();
		1504	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1505	Net::SSLeay::randomize ();
		1506
		1507	$TLS_CTX = Net::SSLeay::CTX_new ();
		1508
		1509	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1510
		1511	$TLS_CTX
		1512	}
		1513	}
		1514
601	=back	1515	=back
602		1516
		1517
		1518	=head1 NONFREQUENTLY ASKED QUESTIONS
		1519
		1520	=over 4
		1521
		1522	=item How do I read data until the other side closes the connection?
		1523
		1524	If you just want to read your data into a perl scalar, the easiest way
		1525	to achieve this is by setting an C<on_read> callback that does nothing,
		1526	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1527	will be in C<$_[0]{rbuf}>:
		1528
		1529	$handle->on_read (sub { });
		1530	$handle->on_eof (undef);
		1531	$handle->on_error (sub {
		1532	my $data = delete $_[0]{rbuf};
		1533	undef $handle;
		1534	});
		1535
		1536	The reason to use C<on_error> is that TCP connections, due to latencies
		1537	and packets loss, might get closed quite violently with an error, when in
		1538	fact, all data has been received.
		1539
		1540	It is usually better to use acknowledgements when transfering data,
		1541	to make sure the other side hasn't just died and you got the data
		1542	intact. This is also one reason why so many internet protocols have an
		1543	explicit QUIT command.
		1544
		1545
		1546	=item I don't want to destroy the handle too early - how do I wait until
		1547	all data has been written?
		1548
		1549	After writing your last bits of data, set the C<on_drain> callback
		1550	and destroy the handle in there - with the default setting of
		1551	C<low_water_mark> this will be called precisely when all data has been
		1552	written to the socket:
		1553
		1554	$handle->push_write (...);
		1555	$handle->on_drain (sub {
		1556	warn "all data submitted to the kernel\n";
		1557	undef $handle;
		1558	});
		1559
		1560	=back
		1561
		1562
		1563	=head1 SUBCLASSING AnyEvent::Handle
		1564
		1565	In many cases, you might want to subclass AnyEvent::Handle.
		1566
		1567	To make this easier, a given version of AnyEvent::Handle uses these
		1568	conventions:
		1569
		1570	=over 4
		1571
		1572	=item * all constructor arguments become object members.
		1573
		1574	At least initially, when you pass a C<tls>-argument to the constructor it
		1575	will end up in C<< $handle->{tls} >>. Those members might be changed or
		1576	mutated later on (for example C<tls> will hold the TLS connection object).
		1577
		1578	=item * other object member names are prefixed with an C<_>.
		1579
		1580	All object members not explicitly documented (internal use) are prefixed
		1581	with an underscore character, so the remaining non-C<_>-namespace is free
		1582	for use for subclasses.
		1583
		1584	=item * all members not documented here and not prefixed with an underscore
		1585	are free to use in subclasses.
		1586
		1587	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1588	member variables, but thats just life, at least it is documented.
		1589
		1590	=back
		1591
603	=head1 AUTHOR	1592	=head1 AUTHOR
604		1593
605	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	1594	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
606		1595
607	=cut	1596	=cut

Diff Legend

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