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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.38 by root, Mon May 26 21:28:33 2008 UTC vs.
Revision 1.104 by root, Mon Nov 3 21:49:25 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 qw(WSAWOULDBLOCK);	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
10	use Fcntl ();	10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;	11	use Errno qw(EAGAIN EINTR);
12		12
13	=head1 NAME	13	=head1 NAME
14		14
15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16		16
17	=cut	17	=cut
18		18
19	our $VERSION = '0.04';	19	our $VERSION = 4.32;
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
…		…
49		49
50	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
52	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
53		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
54	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
55	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
56	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
57		60
58	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
…		…
70		73
71	=item fh => $filehandle [MANDATORY]	74	=item fh => $filehandle [MANDATORY]
72		75
73	The filehandle this L<AnyEvent::Handle> object will operate on.	76	The filehandle this L<AnyEvent::Handle> object will operate on.
74		77
75	NOTE: The filehandle will be set to non-blocking (using	78	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
77		81
78	=item on_eof => $cb->($self)	82	=item on_eof => $cb->($handle)
79		83
80	Set the callback to be called on EOF.	84	Set the callback to be called when an end-of-file condition is detected,
		85	i.e. in the case of a socket, when the other side has closed the
		86	connection cleanly.
81		87
		88	For sockets, this just means that the other side has stopped sending data,
		89	you can still try to write data, and, in fact, one can return from the EOF
		90	callback and continue writing data, as only the read part has been shut
		91	down.
		92
82	While not mandatory, it is highly recommended to set an eof callback,	93	While not mandatory, it is I<highly> recommended to set an EOF callback,
83	otherwise you might end up with a closed socket while you are still	94	otherwise you might end up with a closed socket while you are still
84	waiting for data.	95	waiting for data.
85		96
		97	If an EOF condition has been detected but no C<on_eof> callback has been
		98	set, then a fatal error will be raised with C<$!> set to <0>.
		99
86	=item on_error => $cb->($self)	100	=item on_error => $cb->($handle, $fatal)
87		101
88	This is the fatal error callback, that is called when, well, a fatal error	102	This is the error callback, which is called when, well, some error
89	occurs, such as not being able to resolve the hostname, failure to connect	103	occured, such as not being able to resolve the hostname, failure to
90	or a read error.	104	connect or a read error.
91		105
92	The object will not be in a usable state when this callback has been	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
93	called.	107	fatal errors the handle object will be shut down and will not be usable
		108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		109	errors are an EOF condition with active (but unsatisifable) read watchers
		110	(C<EPIPE>) or I/O errors.
		111
		112	Non-fatal errors can be retried by simply returning, but it is recommended
		113	to simply ignore this parameter and instead abondon the handle object
		114	when this callback is invoked. Examples of non-fatal errors are timeouts
		115	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
94		116
95	On callback entrance, the value of C<$!> contains the operating system	117	On callback entrance, the value of C<$!> contains the operating system
96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).	118	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
97
98	The callback should throw an exception. If it returns, then
99	AnyEvent::Handle will C<croak> for you.
100		119
101	While not mandatory, it is I<highly> recommended to set this callback, as	120	While not mandatory, it is I<highly> recommended to set this callback, as
102	you will not be notified of errors otherwise. The default simply calls	121	you will not be notified of errors otherwise. The default simply calls
103	die.	122	C<croak>.
104		123
105	=item on_read => $cb->($self)	124	=item on_read => $cb->($handle)
106		125
107	This sets the default read callback, which is called when data arrives	126	This sets the default read callback, which is called when data arrives
108	and no read request is in the queue.	127	and no read request is in the queue (unlike read queue callbacks, this
		128	callback will only be called when at least one octet of data is in the
		129	read buffer).
109		130
110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	131	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111	method or access the C<$self->{rbuf}> member directly.	132	method or access the C<$handle->{rbuf}> member directly.
112		133
113	When an EOF condition is detected then AnyEvent::Handle will first try to	134	When an EOF condition is detected then AnyEvent::Handle will first try to
114	feed all the remaining data to the queued callbacks and C<on_read> before	135	feed all the remaining data to the queued callbacks and C<on_read> before
115	calling the C<on_eof> callback. If no progress can be made, then a fatal	136	calling the C<on_eof> callback. If no progress can be made, then a fatal
116	error will be raised (with C<$!> set to C<EPIPE>).	137	error will be raised (with C<$!> set to C<EPIPE>).
117		138
118	=item on_drain => $cb->()	139	=item on_drain => $cb->($handle)
119		140
120	This sets the callback that is called when the write buffer becomes empty	141	This sets the callback that is called when the write buffer becomes empty
121	(or when the callback is set and the buffer is empty already).	142	(or when the callback is set and the buffer is empty already).
122		143
123	To append to the write buffer, use the C<< ->push_write >> method.	144	To append to the write buffer, use the C<< ->push_write >> method.
124		145
		146	This callback is useful when you don't want to put all of your write data
		147	into the queue at once, for example, when you want to write the contents
		148	of some file to the socket you might not want to read the whole file into
		149	memory and push it into the queue, but instead only read more data from
		150	the file when the write queue becomes empty.
		151
		152	=item timeout => $fractional_seconds
		153
		154	If non-zero, then this enables an "inactivity" timeout: whenever this many
		155	seconds pass without a successful read or write on the underlying file
		156	handle, the C<on_timeout> callback will be invoked (and if that one is
		157	missing, a non-fatal C<ETIMEDOUT> error will be raised).
		158
		159	Note that timeout processing is also active when you currently do not have
		160	any outstanding read or write requests: If you plan to keep the connection
		161	idle then you should disable the timout temporarily or ignore the timeout
		162	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		163	restart the timeout.
		164
		165	Zero (the default) disables this timeout.
		166
		167	=item on_timeout => $cb->($handle)
		168
		169	Called whenever the inactivity timeout passes. If you return from this
		170	callback, then the timeout will be reset as if some activity had happened,
		171	so this condition is not fatal in any way.
		172
125	=item rbuf_max => <bytes>	173	=item rbuf_max => <bytes>
126		174
127	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	175	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128	when the read buffer ever (strictly) exceeds this size. This is useful to	176	when the read buffer ever (strictly) exceeds this size. This is useful to
129	avoid denial-of-service attacks.	177	avoid some forms of denial-of-service attacks.
130		178
131	For example, a server accepting connections from untrusted sources should	179	For example, a server accepting connections from untrusted sources should
132	be configured to accept only so-and-so much data that it cannot act on	180	be configured to accept only so-and-so much data that it cannot act on
133	(for example, when expecting a line, an attacker could send an unlimited	181	(for example, when expecting a line, an attacker could send an unlimited
134	amount of data without a callback ever being called as long as the line	182	amount of data without a callback ever being called as long as the line
135	isn't finished).	183	isn't finished).
136		184
		185	=item autocork => <boolean>
		186
		187	When disabled (the default), then C<push_write> will try to immediately
		188	write the data to the handle, if possible. This avoids having to register
		189	a write watcher and wait for the next event loop iteration, but can
		190	be inefficient if you write multiple small chunks (on the wire, this
		191	disadvantage is usually avoided by your kernel's nagle algorithm, see
		192	C<no_delay>, but this option can save costly syscalls).
		193
		194	When enabled, then writes will always be queued till the next event loop
		195	iteration. This is efficient when you do many small writes per iteration,
		196	but less efficient when you do a single write only per iteration (or when
		197	the write buffer often is full). It also increases write latency.
		198
		199	=item no_delay => <boolean>
		200
		201	When doing small writes on sockets, your operating system kernel might
		202	wait a bit for more data before actually sending it out. This is called
		203	the Nagle algorithm, and usually it is beneficial.
		204
		205	In some situations you want as low a delay as possible, which can be
		206	accomplishd by setting this option to a true value.
		207
		208	The default is your opertaing system's default behaviour (most likely
		209	enabled), this option explicitly enables or disables it, if possible.
		210
137	=item read_size => <bytes>	211	=item read_size => <bytes>
138		212
139	The default read block size (the amount of bytes this module will try to read	213	The default read block size (the amount of bytes this module will
140	on each [loop iteration). Default: C<4096>.	214	try to read during each loop iteration, which affects memory
		215	requirements). Default: C<8192>.
141		216
142	=item low_water_mark => <bytes>	217	=item low_water_mark => <bytes>
143		218
144	Sets the amount of bytes (default: C<0>) that make up an "empty" write	219	Sets the amount of bytes (default: C<0>) that make up an "empty" write
145	buffer: If the write reaches this size or gets even samller it is	220	buffer: If the write reaches this size or gets even samller it is
146	considered empty.	221	considered empty.
147		222
		223	Sometimes it can be beneficial (for performance reasons) to add data to
		224	the write buffer before it is fully drained, but this is a rare case, as
		225	the operating system kernel usually buffers data as well, so the default
		226	is good in almost all cases.
		227
		228	=item linger => <seconds>
		229
		230	If non-zero (default: C<3600>), then the destructor of the
		231	AnyEvent::Handle object will check whether there is still outstanding
		232	write data and will install a watcher that will write this data to the
		233	socket. No errors will be reported (this mostly matches how the operating
		234	system treats outstanding data at socket close time).
		235
		236	This will not work for partial TLS data that could not be encoded
		237	yet. This data will be lost. Calling the C<stoptls> method in time might
		238	help.
		239
148	=item tls => "accept" | "connect" | Net::SSLeay::SSL object	240	=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149		241
150	When this parameter is given, it enables TLS (SSL) mode, that means it	242	When this parameter is given, it enables TLS (SSL) mode, that means
151	will start making tls handshake and will transparently encrypt/decrypt	243	AnyEvent will start a TLS handshake as soon as the conenction has been
152	data.	244	established and will transparently encrypt/decrypt data afterwards.
153		245
154	TLS mode requires Net::SSLeay to be installed (it will be loaded	246	TLS mode requires Net::SSLeay to be installed (it will be loaded
155	automatically when you try to create a TLS handle).	247	automatically when you try to create a TLS handle): this module doesn't
		248	have a dependency on that module, so if your module requires it, you have
		249	to add the dependency yourself.
156		250
157	For the TLS server side, use C<accept>, and for the TLS client side of a	251	Unlike TCP, TLS has a server and client side: for the TLS server side, use
158	connection, use C<connect> mode.	252	C<accept>, and for the TLS client side of a connection, use C<connect>
		253	mode.
159		254
160	You can also provide your own TLS connection object, but you have	255	You can also provide your own TLS connection object, but you have
161	to make sure that you call either C<Net::SSLeay::set_connect_state>	256	to make sure that you call either C<Net::SSLeay::set_connect_state>
162	or C<Net::SSLeay::set_accept_state> on it before you pass it to	257	or C<Net::SSLeay::set_accept_state> on it before you pass it to
163	AnyEvent::Handle.	258	AnyEvent::Handle.
164		259
165	See the C<starttls> method if you need to start TLs negotiation later.	260	See the C<< ->starttls >> method for when need to start TLS negotiation later.
166		261
167	=item tls_ctx => $ssl_ctx	262	=item tls_ctx => $ssl_ctx
168		263
169	Use the given Net::SSLeay::CTX object to create the new TLS connection	264	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
170	(unless a connection object was specified directly). If this parameter is	265	(unless a connection object was specified directly). If this parameter is
171	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	266	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172		267
173	=item filter_r => $cb	268	=item json => JSON or JSON::XS object
174		269
175	=item filter_w => $cb	270	This is the json coder object used by the C<json> read and write types.
176		271
177	These exist, but are undocumented at this time.	272	If you don't supply it, then AnyEvent::Handle will create and use a
		273	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		274	texts.
		275
		276	Note that you are responsible to depend on the JSON module if you want to
		277	use this functionality, as AnyEvent does not have a dependency itself.
178		278
179	=back	279	=back
180		280
181	=cut	281	=cut
182		282
…		…
187		287
188	$self->{fh} or Carp::croak "mandatory argument fh is missing";	288	$self->{fh} or Carp::croak "mandatory argument fh is missing";
189		289
190	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	290	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
191		291
192	if ($self->{tls}) {
193	require Net::SSLeay;
194	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	292	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
195	}	293	if $self->{tls};
196		294
197	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};	295	$self->{_activity} = AnyEvent->now;
198	$self->on_error (delete $self->{on_error}) if $self->{on_error};	296	$self->_timeout;
		297
199	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	298	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
200	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	299	$self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
201		300
202	$self->start_read;	301	$self->start_read
		302	if $self->{on_read};
203		303
204	$self	304	$self
205	}	305	}
206		306
207	sub _shutdown {	307	sub _shutdown {
208	my ($self) = @_;	308	my ($self) = @_;
209		309
		310	delete $self->{_tw};
210	delete $self->{_rw};	311	delete $self->{_rw};
211	delete $self->{_ww};	312	delete $self->{_ww};
212	delete $self->{fh};	313	delete $self->{fh};
213	}
214		314
		315	&_freetls;
		316
		317	delete $self->{on_read};
		318	delete $self->{_queue};
		319	}
		320
215	sub error {	321	sub _error {
216	my ($self) = @_;	322	my ($self, $errno, $fatal) = @_;
217		323
218	{
219	local $!;
220	$self->_shutdown;	324	$self->_shutdown
221	}	325	if $fatal;
222		326
223	$self->{on_error}($self)	327	$! = $errno;
		328
224	if $self->{on_error};	329	if ($self->{on_error}) {
225		330	$self->{on_error}($self, $fatal);
		331	} elsif ($self->{fh}) {
226	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";	332	Carp::croak "AnyEvent::Handle uncaught error: $!";
		333	}
227	}	334	}
228		335
229	=item $fh = $handle->fh	336	=item $fh = $handle->fh
230		337
231	This method returns the file handle of the L<AnyEvent::Handle> object.	338	This method returns the file handle used to create the L<AnyEvent::Handle> object.
232		339
233	=cut	340	=cut
234		341
235	sub fh { $_[0]{fh} }	342	sub fh { $_[0]{fh} }
236		343
…		…
252		359
253	sub on_eof {	360	sub on_eof {
254	$_[0]{on_eof} = $_[1];	361	$_[0]{on_eof} = $_[1];
255	}	362	}
256		363
		364	=item $handle->on_timeout ($cb)
		365
		366	Replace the current C<on_timeout> callback, or disables the callback (but
		367	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
		368	argument and method.
		369
		370	=cut
		371
		372	sub on_timeout {
		373	$_[0]{on_timeout} = $_[1];
		374	}
		375
		376	=item $handle->autocork ($boolean)
		377
		378	Enables or disables the current autocork behaviour (see C<autocork>
		379	constructor argument).
		380
		381	=cut
		382
		383	=item $handle->no_delay ($boolean)
		384
		385	Enables or disables the C<no_delay> setting (see constructor argument of
		386	the same name for details).
		387
		388	=cut
		389
		390	sub no_delay {
		391	$_[0]{no_delay} = $_[1];
		392
		393	eval {
		394	local $SIG{__DIE__};
		395	setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
		396	};
		397	}
		398
		399	#############################################################################
		400
		401	=item $handle->timeout ($seconds)
		402
		403	Configures (or disables) the inactivity timeout.
		404
		405	=cut
		406
		407	sub timeout {
		408	my ($self, $timeout) = @_;
		409
		410	$self->{timeout} = $timeout;
		411	$self->_timeout;
		412	}
		413
		414	# reset the timeout watcher, as neccessary
		415	# also check for time-outs
		416	sub _timeout {
		417	my ($self) = @_;
		418
		419	if ($self->{timeout}) {
		420	my $NOW = AnyEvent->now;
		421
		422	# when would the timeout trigger?
		423	my $after = $self->{_activity} + $self->{timeout} - $NOW;
		424
		425	# now or in the past already?
		426	if ($after <= 0) {
		427	$self->{_activity} = $NOW;
		428
		429	if ($self->{on_timeout}) {
		430	$self->{on_timeout}($self);
		431	} else {
		432	$self->_error (&Errno::ETIMEDOUT);
		433	}
		434
		435	# callback could have changed timeout value, optimise
		436	return unless $self->{timeout};
		437
		438	# calculate new after
		439	$after = $self->{timeout};
		440	}
		441
		442	Scalar::Util::weaken $self;
		443	return unless $self; # ->error could have destroyed $self
		444
		445	$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
		446	delete $self->{_tw};
		447	$self->_timeout;
		448	});
		449	} else {
		450	delete $self->{_tw};
		451	}
		452	}
		453
257	#############################################################################	454	#############################################################################
258		455
259	=back	456	=back
260		457
261	=head2 WRITE QUEUE	458	=head2 WRITE QUEUE
…		…
282	my ($self, $cb) = @_;	479	my ($self, $cb) = @_;
283		480
284	$self->{on_drain} = $cb;	481	$self->{on_drain} = $cb;
285		482
286	$cb->($self)	483	$cb->($self)
287	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	484	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
288	}	485	}
289		486
290	=item $handle->push_write ($data)	487	=item $handle->push_write ($data)
291		488
292	Queues the given scalar to be written. You can push as much data as you	489	Queues the given scalar to be written. You can push as much data as you
…		…
306	my $len = syswrite $self->{fh}, $self->{wbuf};	503	my $len = syswrite $self->{fh}, $self->{wbuf};
307		504
308	if ($len >= 0) {	505	if ($len >= 0) {
309	substr $self->{wbuf}, 0, $len, "";	506	substr $self->{wbuf}, 0, $len, "";
310		507
		508	$self->{_activity} = AnyEvent->now;
		509
311	$self->{on_drain}($self)	510	$self->{on_drain}($self)
312	if $self->{low_water_mark} >= length $self->{wbuf}	511	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
313	&& $self->{on_drain};	512	&& $self->{on_drain};
314		513
315	delete $self->{_ww} unless length $self->{wbuf};	514	delete $self->{_ww} unless length $self->{wbuf};
316	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) {	515	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
317	$self->error;	516	$self->_error ($!, 1);
318	}	517	}
319	};	518	};
320		519
321	# try to write data immediately	520	# try to write data immediately
322	$cb->();	521	$cb->() unless $self->{autocork};
323		522
324	# if still data left in wbuf, we need to poll	523	# if still data left in wbuf, we need to poll
325	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)	524	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
326	if length $self->{wbuf};	525	if length $self->{wbuf};
327	};	526	};
…		…
341		540
342	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	541	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
343	->($self, @_);	542	->($self, @_);
344	}	543	}
345		544
346	if ($self->{filter_w}) {	545	if ($self->{tls}) {
347	$self->{filter_w}->($self, \$_[0]);	546	$self->{_tls_wbuf} .= $_[0];
		547
		548	&_dotls ($self);
348	} else {	549	} else {
349	$self->{wbuf} .= $_[0];	550	$self->{wbuf} .= $_[0];
350	$self->_drain_wbuf;	551	$self->_drain_wbuf;
351	}	552	}
352	}	553	}
353		554
354	=item $handle->push_write (type => @args)	555	=item $handle->push_write (type => @args)
355		556
356	=item $handle->unshift_write (type => @args)
357
358	Instead of formatting your data yourself, you can also let this module do	557	Instead of formatting your data yourself, you can also let this module do
359	the job by specifying a type and type-specific arguments.	558	the job by specifying a type and type-specific arguments.
360		559
361	Predefined types are (if you have ideas for additional types, feel free to	560	Predefined types are (if you have ideas for additional types, feel free to
362	drop by and tell us):	561	drop by and tell us):
…		…
366	=item netstring => $string	565	=item netstring => $string
367		566
368	Formats the given value as netstring	567	Formats the given value as netstring
369	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).	568	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
370		569
371	=back
372
373	=cut	570	=cut
374		571
375	register_write_type netstring => sub {	572	register_write_type netstring => sub {
376	my ($self, $string) = @_;	573	my ($self, $string) = @_;
377		574
378	sprintf "%d:%s,", (length $string), $string	575	(length $string) . ":$string,"
379	};	576	};
380		577
		578	=item packstring => $format, $data
		579
		580	An octet string prefixed with an encoded length. The encoding C<$format>
		581	uses the same format as a Perl C<pack> format, but must specify a single
		582	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		583	optional C<!>, C<< < >> or C<< > >> modifier).
		584
		585	=cut
		586
		587	register_write_type packstring => sub {
		588	my ($self, $format, $string) = @_;
		589
		590	pack "$format/a*", $string
		591	};
		592
		593	=item json => $array_or_hashref
		594
		595	Encodes the given hash or array reference into a JSON object. Unless you
		596	provide your own JSON object, this means it will be encoded to JSON text
		597	in UTF-8.
		598
		599	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		600	one end of a handle and read them at the other end without using any
		601	additional framing.
		602
		603	The generated JSON text is guaranteed not to contain any newlines: While
		604	this module doesn't need delimiters after or between JSON texts to be
		605	able to read them, many other languages depend on that.
		606
		607	A simple RPC protocol that interoperates easily with others is to send
		608	JSON arrays (or objects, although arrays are usually the better choice as
		609	they mimic how function argument passing works) and a newline after each
		610	JSON text:
		611
		612	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		613	$handle->push_write ("\012");
		614
		615	An AnyEvent::Handle receiver would simply use the C<json> read type and
		616	rely on the fact that the newline will be skipped as leading whitespace:
		617
		618	$handle->push_read (json => sub { my $array = $_[1]; ... });
		619
		620	Other languages could read single lines terminated by a newline and pass
		621	this line into their JSON decoder of choice.
		622
		623	=cut
		624
		625	register_write_type json => sub {
		626	my ($self, $ref) = @_;
		627
		628	require JSON;
		629
		630	$self->{json} ? $self->{json}->encode ($ref)
		631	: JSON::encode_json ($ref)
		632	};
		633
		634	=item storable => $reference
		635
		636	Freezes the given reference using L<Storable> and writes it to the
		637	handle. Uses the C<nfreeze> format.
		638
		639	=cut
		640
		641	register_write_type storable => sub {
		642	my ($self, $ref) = @_;
		643
		644	require Storable;
		645
		646	pack "w/a*", Storable::nfreeze ($ref)
		647	};
		648
		649	=back
		650
381	=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args)	651	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
382		652
383	This function (not method) lets you add your own types to C<push_write>.	653	This function (not method) lets you add your own types to C<push_write>.
384	Whenever the given C<type> is used, C<push_write> will invoke the code	654	Whenever the given C<type> is used, C<push_write> will invoke the code
385	reference with the handle object and the remaining arguments.	655	reference with the handle object and the remaining arguments.
386		656
…		…
405	ways, the "simple" way, using only C<on_read> and the "complex" way, using	675	ways, the "simple" way, using only C<on_read> and the "complex" way, using
406	a queue.	676	a queue.
407		677
408	In the simple case, you just install an C<on_read> callback and whenever	678	In the simple case, you just install an C<on_read> callback and whenever
409	new data arrives, it will be called. You can then remove some data (if	679	new data arrives, it will be called. You can then remove some data (if
410	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want	680	enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
411	or not.	681	leave the data there if you want to accumulate more (e.g. when only a
		682	partial message has been received so far).
412		683
413	In the more complex case, you want to queue multiple callbacks. In this	684	In the more complex case, you want to queue multiple callbacks. In this
414	case, AnyEvent::Handle will call the first queued callback each time new	685	case, AnyEvent::Handle will call the first queued callback each time new
415	data arrives and removes it when it has done its job (see C<push_read>,	686	data arrives (also the first time it is queued) and removes it when it has
416	below).	687	done its job (see C<push_read>, below).
417		688
418	This way you can, for example, push three line-reads, followed by reading	689	This way you can, for example, push three line-reads, followed by reading
419	a chunk of data, and AnyEvent::Handle will execute them in order.	690	a chunk of data, and AnyEvent::Handle will execute them in order.
420		691
421	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by	692	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
422	the specified number of bytes which give an XML datagram.	693	the specified number of bytes which give an XML datagram.
423		694
424	# in the default state, expect some header bytes	695	# in the default state, expect some header bytes
425	$handle->on_read (sub {	696	$handle->on_read (sub {
426	# some data is here, now queue the length-header-read (4 octets)	697	# some data is here, now queue the length-header-read (4 octets)
427	shift->unshift_read_chunk (4, sub {	698	shift->unshift_read (chunk => 4, sub {
428	# header arrived, decode	699	# header arrived, decode
429	my $len = unpack "N", $_[1];	700	my $len = unpack "N", $_[1];
430		701
431	# now read the payload	702	# now read the payload
432	shift->unshift_read_chunk ($len, sub {	703	shift->unshift_read (chunk => $len, sub {
433	my $xml = $_[1];	704	my $xml = $_[1];
434	# handle xml	705	# handle xml
435	});	706	});
436	});	707	});
437	});	708	});
438		709
439	Example 2: Implement a client for a protocol that replies either with	710	Example 2: Implement a client for a protocol that replies either with "OK"
440	"OK" and another line or "ERROR" for one request, and 64 bytes for the	711	and another line or "ERROR" for the first request that is sent, and 64
441	second request. Due tot he availability of a full queue, we can just	712	bytes for the second request. Due to the availability of a queue, we can
442	pipeline sending both requests and manipulate the queue as necessary in	713	just pipeline sending both requests and manipulate the queue as necessary
443	the callbacks:	714	in the callbacks.
444		715
445	# request one	716	When the first callback is called and sees an "OK" response, it will
		717	C<unshift> another line-read. This line-read will be queued I<before> the
		718	64-byte chunk callback.
		719
		720	# request one, returns either "OK + extra line" or "ERROR"
446	$handle->push_write ("request 1\015\012");	721	$handle->push_write ("request 1\015\012");
447		722
448	# we expect "ERROR" or "OK" as response, so push a line read	723	# we expect "ERROR" or "OK" as response, so push a line read
449	$handle->push_read_line (sub {	724	$handle->push_read (line => sub {
450	# if we got an "OK", we have to _prepend_ another line,	725	# if we got an "OK", we have to _prepend_ another line,
451	# so it will be read before the second request reads its 64 bytes	726	# so it will be read before the second request reads its 64 bytes
452	# which are already in the queue when this callback is called	727	# which are already in the queue when this callback is called
453	# we don't do this in case we got an error	728	# we don't do this in case we got an error
454	if ($_[1] eq "OK") {	729	if ($_[1] eq "OK") {
455	$_[0]->unshift_read_line (sub {	730	$_[0]->unshift_read (line => sub {
456	my $response = $_[1];	731	my $response = $_[1];
457	...	732	...
458	});	733	});
459	}	734	}
460	});	735	});
461		736
462	# request two	737	# request two, simply returns 64 octets
463	$handle->push_write ("request 2\015\012");	738	$handle->push_write ("request 2\015\012");
464		739
465	# simply read 64 bytes, always	740	# simply read 64 bytes, always
466	$handle->push_read_chunk (64, sub {	741	$handle->push_read (chunk => 64, sub {
467	my $response = $_[1];	742	my $response = $_[1];
468	...	743	...
469	});	744	});
470		745
471	=over 4	746	=over 4
472		747
473	=cut	748	=cut
474		749
475	sub _drain_rbuf {	750	sub _drain_rbuf {
476	my ($self) = @_;	751	my ($self) = @_;
		752
		753	local $self->{_in_drain} = 1;
477		754
478	if (	755	if (
479	defined $self->{rbuf_max}	756	defined $self->{rbuf_max}
480	&& $self->{rbuf_max} < length $self->{rbuf}	757	&& $self->{rbuf_max} < length $self->{rbuf}
481	) {	758	) {
482	$! = &Errno::ENOSPC;	759	$self->_error (&Errno::ENOSPC, 1), return;
483	$self->error;
484	}	760	}
485		761
486	return if $self->{in_drain};	762	while () {
487	local $self->{in_drain} = 1;
488
489	while (my $len = length $self->{rbuf}) {	763	my $len = length $self->{rbuf};
490	no strict 'refs';	764
491	if (my $cb = shift @{ $self->{_queue} }) {	765	if (my $cb = shift @{ $self->{_queue} }) {
492	unless ($cb->($self)) {	766	unless ($cb->($self)) {
493	if ($self->{_eof}) {	767	if ($self->{_eof}) {
494	# no progress can be made (not enough data and no data forthcoming)	768	# no progress can be made (not enough data and no data forthcoming)
495	$! = &Errno::EPIPE;	769	$self->_error (&Errno::EPIPE, 1), return;
496	$self->error;
497	}	770	}
498		771
499	unshift @{ $self->{_queue} }, $cb;	772	unshift @{ $self->{_queue} }, $cb;
500	return;	773	last;
501	}	774	}
502	} elsif ($self->{on_read}) {	775	} elsif ($self->{on_read}) {
		776	last unless $len;
		777
503	$self->{on_read}($self);	778	$self->{on_read}($self);
504		779
505	if (	780	if (
506	$self->{_eof} # if no further data will arrive
507	&& $len == length $self->{rbuf} # and no data has been consumed	781	$len == length $self->{rbuf} # if no data has been consumed
508	&& !@{ $self->{_queue} } # and the queue is still empty	782	&& !@{ $self->{_queue} } # and the queue is still empty
509	&& $self->{on_read} # and we still want to read data	783	&& $self->{on_read} # but we still have on_read
510	) {	784	) {
		785	# no further data will arrive
511	# then no progress can be made	786	# so no progress can be made
512	$! = &Errno::EPIPE;	787	$self->_error (&Errno::EPIPE, 1), return
513	$self->error;	788	if $self->{_eof};
		789
		790	last; # more data might arrive
514	}	791	}
515	} else {	792	} else {
516	# read side becomes idle	793	# read side becomes idle
517	delete $self->{_rw};	794	delete $self->{_rw} unless $self->{tls};
518	return;	795	last;
519	}	796	}
520	}	797	}
521		798
522	if ($self->{_eof}) {	799	if ($self->{_eof}) {
523	$self->_shutdown;	800	if ($self->{on_eof}) {
524	$self->{on_eof}($self)	801	$self->{on_eof}($self)
525	if $self->{on_eof};	802	} else {
		803	$self->_error (0, 1);
		804	}
		805	}
		806
		807	# may need to restart read watcher
		808	unless ($self->{_rw}) {
		809	$self->start_read
		810	if $self->{on_read} || @{ $self->{_queue} };
526	}	811	}
527	}	812	}
528		813
529	=item $handle->on_read ($cb)	814	=item $handle->on_read ($cb)
530		815
…		…
536		821
537	sub on_read {	822	sub on_read {
538	my ($self, $cb) = @_;	823	my ($self, $cb) = @_;
539		824
540	$self->{on_read} = $cb;	825	$self->{on_read} = $cb;
		826	$self->_drain_rbuf if $cb && !$self->{_in_drain};
541	}	827	}
542		828
543	=item $handle->rbuf	829	=item $handle->rbuf
544		830
545	Returns the read buffer (as a modifiable lvalue).	831	Returns the read buffer (as a modifiable lvalue).
…		…
594	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")	880	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
595	->($self, $cb, @_);	881	->($self, $cb, @_);
596	}	882	}
597		883
598	push @{ $self->{_queue} }, $cb;	884	push @{ $self->{_queue} }, $cb;
599	$self->_drain_rbuf;	885	$self->_drain_rbuf unless $self->{_in_drain};
600	}	886	}
601		887
602	sub unshift_read {	888	sub unshift_read {
603	my $self = shift;	889	my $self = shift;
604	my $cb = pop;	890	my $cb = pop;
…		…
610	->($self, $cb, @_);	896	->($self, $cb, @_);
611	}	897	}
612		898
613		899
614	unshift @{ $self->{_queue} }, $cb;	900	unshift @{ $self->{_queue} }, $cb;
615	$self->_drain_rbuf;	901	$self->_drain_rbuf unless $self->{_in_drain};
616	}	902	}
617		903
618	=item $handle->push_read (type => @args, $cb)	904	=item $handle->push_read (type => @args, $cb)
619		905
620	=item $handle->unshift_read (type => @args, $cb)	906	=item $handle->unshift_read (type => @args, $cb)
…		…
626	Predefined types are (if you have ideas for additional types, feel free to	912	Predefined types are (if you have ideas for additional types, feel free to
627	drop by and tell us):	913	drop by and tell us):
628		914
629	=over 4	915	=over 4
630		916
631	=item chunk => $octets, $cb->($self, $data)	917	=item chunk => $octets, $cb->($handle, $data)
632		918
633	Invoke the callback only once C<$octets> bytes have been read. Pass the	919	Invoke the callback only once C<$octets> bytes have been read. Pass the
634	data read to the callback. The callback will never be called with less	920	data read to the callback. The callback will never be called with less
635	data.	921	data.
636		922
…		…
650	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	936	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
651	1	937	1
652	}	938	}
653	};	939	};
654		940
655	# compatibility with older API
656	sub push_read_chunk {
657	$_[0]->push_read (chunk => $_[1], $_[2]);
658	}
659
660	sub unshift_read_chunk {
661	$_[0]->unshift_read (chunk => $_[1], $_[2]);
662	}
663
664	=item line => [$eol, ]$cb->($self, $line, $eol)	941	=item line => [$eol, ]$cb->($handle, $line, $eol)
665		942
666	The callback will be called only once a full line (including the end of	943	The callback will be called only once a full line (including the end of
667	line marker, C<$eol>) has been read. This line (excluding the end of line	944	line marker, C<$eol>) has been read. This line (excluding the end of line
668	marker) will be passed to the callback as second argument (C<$line>), and	945	marker) will be passed to the callback as second argument (C<$line>), and
669	the end of line marker as the third argument (C<$eol>).	946	the end of line marker as the third argument (C<$eol>).
…		…
683	=cut	960	=cut
684		961
685	register_read_type line => sub {	962	register_read_type line => sub {
686	my ($self, $cb, $eol) = @_;	963	my ($self, $cb, $eol) = @_;
687		964
688	$eol = qr|(\015?\012)| if @_ < 3;	965	if (@_ < 3) {
		966	# this is more than twice as fast as the generic code below
		967	sub {
		968	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
		969
		970	$cb->($_[0], $1, $2);
		971	1
		972	}
		973	} else {
689	$eol = quotemeta $eol unless ref $eol;	974	$eol = quotemeta $eol unless ref $eol;
690	$eol = qr|^(.*?)($eol)|s;	975	$eol = qr|^(.*?)($eol)|s;
691		976
692	sub {	977	sub {
693	$_[0]{rbuf} =~ s/$eol// or return;	978	$_[0]{rbuf} =~ s/$eol// or return;
694		979
695	$cb->($_[0], $1, $2);	980	$cb->($_[0], $1, $2);
		981	1
696	1	982	}
697	}	983	}
698	};	984	};
699		985
700	# compatibility with older API
701	sub push_read_line {
702	my $self = shift;
703	$self->push_read (line => @_);
704	}
705
706	sub unshift_read_line {
707	my $self = shift;
708	$self->unshift_read (line => @_);
709	}
710
711	=item netstring => $cb->($string)
712
713	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
714
715	Throws an error with C<$!> set to EBADMSG on format violations.
716
717	=cut
718
719	register_read_type netstring => sub {
720	my ($self, $cb) = @_;
721
722	sub {
723	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
724	if ($_[0]{rbuf} =~ /[^0-9]/) {
725	$! = &Errno::EBADMSG;
726	$self->error;
727	}
728	return;
729	}
730
731	my $len = $1;
732
733	$self->unshift_read (chunk => $len, sub {
734	my $string = $_[1];
735	$_[0]->unshift_read (chunk => 1, sub {
736	if ($_[1] eq ",") {
737	$cb->($_[0], $string);
738	} else {
739	$! = &Errno::EBADMSG;
740	$self->error;
741	}
742	});
743	});
744
745	1
746	}
747	};
748
749	=item regex => $accept[, $reject[, $skip], $cb->($data)	986	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
750		987
751	Makes a regex match against the regex object C<$accept> and returns	988	Makes a regex match against the regex object C<$accept> and returns
752	everything up to and including the match.	989	everything up to and including the match.
753		990
754	Example: read a single line terminated by '\n'.	991	Example: read a single line terminated by '\n'.
…		…
802	return 1;	1039	return 1;
803	}	1040	}
804		1041
805	# reject	1042	# reject
806	if ($reject && $$rbuf =~ $reject) {	1043	if ($reject && $$rbuf =~ $reject) {
807	$! = &Errno::EBADMSG;	1044	$self->_error (&Errno::EBADMSG);
808	$self->error;
809	}	1045	}
810		1046
811	# skip	1047	# skip
812	if ($skip && $$rbuf =~ $skip) {	1048	if ($skip && $$rbuf =~ $skip) {
813	$data .= substr $$rbuf, 0, $+[0], "";	1049	$data .= substr $$rbuf, 0, $+[0], "";
…		…
815		1051
816	()	1052	()
817	}	1053	}
818	};	1054	};
819		1055
		1056	=item netstring => $cb->($handle, $string)
		1057
		1058	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		1059
		1060	Throws an error with C<$!> set to EBADMSG on format violations.
		1061
		1062	=cut
		1063
		1064	register_read_type netstring => sub {
		1065	my ($self, $cb) = @_;
		1066
		1067	sub {
		1068	unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
		1069	if ($_[0]{rbuf} =~ /[^0-9]/) {
		1070	$self->_error (&Errno::EBADMSG);
		1071	}
		1072	return;
		1073	}
		1074
		1075	my $len = $1;
		1076
		1077	$self->unshift_read (chunk => $len, sub {
		1078	my $string = $_[1];
		1079	$_[0]->unshift_read (chunk => 1, sub {
		1080	if ($_[1] eq ",") {
		1081	$cb->($_[0], $string);
		1082	} else {
		1083	$self->_error (&Errno::EBADMSG);
		1084	}
		1085	});
		1086	});
		1087
		1088	1
		1089	}
		1090	};
		1091
		1092	=item packstring => $format, $cb->($handle, $string)
		1093
		1094	An octet string prefixed with an encoded length. The encoding C<$format>
		1095	uses the same format as a Perl C<pack> format, but must specify a single
		1096	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
		1097	optional C<!>, C<< < >> or C<< > >> modifier).
		1098
		1099	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1100	EPP uses a prefix of C<N> (4 octtes).
		1101
		1102	Example: read a block of data prefixed by its length in BER-encoded
		1103	format (very efficient).
		1104
		1105	$handle->push_read (packstring => "w", sub {
		1106	my ($handle, $data) = @_;
		1107	});
		1108
		1109	=cut
		1110
		1111	register_read_type packstring => sub {
		1112	my ($self, $cb, $format) = @_;
		1113
		1114	sub {
		1115	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1116	defined (my $len = eval { unpack $format, $_[0]{rbuf} })
		1117	or return;
		1118
		1119	$format = length pack $format, $len;
		1120
		1121	# bypass unshift if we already have the remaining chunk
		1122	if ($format + $len <= length $_[0]{rbuf}) {
		1123	my $data = substr $_[0]{rbuf}, $format, $len;
		1124	substr $_[0]{rbuf}, 0, $format + $len, "";
		1125	$cb->($_[0], $data);
		1126	} else {
		1127	# remove prefix
		1128	substr $_[0]{rbuf}, 0, $format, "";
		1129
		1130	# read remaining chunk
		1131	$_[0]->unshift_read (chunk => $len, $cb);
		1132	}
		1133
		1134	1
		1135	}
		1136	};
		1137
		1138	=item json => $cb->($handle, $hash_or_arrayref)
		1139
		1140	Reads a JSON object or array, decodes it and passes it to the callback.
		1141
		1142	If a C<json> object was passed to the constructor, then that will be used
		1143	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		1144
		1145	This read type uses the incremental parser available with JSON version
		1146	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		1147	dependency on your own: this module will load the JSON module, but
		1148	AnyEvent does not depend on it itself.
		1149
		1150	Since JSON texts are fully self-delimiting, the C<json> read and write
		1151	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		1152	the C<json> write type description, above, for an actual example.
		1153
		1154	=cut
		1155
		1156	register_read_type json => sub {
		1157	my ($self, $cb) = @_;
		1158
		1159	require JSON;
		1160
		1161	my $data;
		1162	my $rbuf = \$self->{rbuf};
		1163
		1164	my $json = $self->{json} ||= JSON->new->utf8;
		1165
		1166	sub {
		1167	my $ref = $json->incr_parse ($self->{rbuf});
		1168
		1169	if ($ref) {
		1170	$self->{rbuf} = $json->incr_text;
		1171	$json->incr_text = "";
		1172	$cb->($self, $ref);
		1173
		1174	1
		1175	} else {
		1176	$self->{rbuf} = "";
		1177	()
		1178	}
		1179	}
		1180	};
		1181
		1182	=item storable => $cb->($handle, $ref)
		1183
		1184	Deserialises a L<Storable> frozen representation as written by the
		1185	C<storable> write type (BER-encoded length prefix followed by nfreeze'd
		1186	data).
		1187
		1188	Raises C<EBADMSG> error if the data could not be decoded.
		1189
		1190	=cut
		1191
		1192	register_read_type storable => sub {
		1193	my ($self, $cb) = @_;
		1194
		1195	require Storable;
		1196
		1197	sub {
		1198	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
		1199	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
		1200	or return;
		1201
		1202	my $format = length pack "w", $len;
		1203
		1204	# bypass unshift if we already have the remaining chunk
		1205	if ($format + $len <= length $_[0]{rbuf}) {
		1206	my $data = substr $_[0]{rbuf}, $format, $len;
		1207	substr $_[0]{rbuf}, 0, $format + $len, "";
		1208	$cb->($_[0], Storable::thaw ($data));
		1209	} else {
		1210	# remove prefix
		1211	substr $_[0]{rbuf}, 0, $format, "";
		1212
		1213	# read remaining chunk
		1214	$_[0]->unshift_read (chunk => $len, sub {
		1215	if (my $ref = eval { Storable::thaw ($_[1]) }) {
		1216	$cb->($_[0], $ref);
		1217	} else {
		1218	$self->_error (&Errno::EBADMSG);
		1219	}
		1220	});
		1221	}
		1222
		1223	1
		1224	}
		1225	};
		1226
820	=back	1227	=back
821		1228
822	=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args)	1229	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
823		1230
824	This function (not method) lets you add your own types to C<push_read>.	1231	This function (not method) lets you add your own types to C<push_read>.
825		1232
826	Whenever the given C<type> is used, C<push_read> will invoke the code	1233	Whenever the given C<type> is used, C<push_read> will invoke the code
827	reference with the handle object, the callback and the remaining	1234	reference with the handle object, the callback and the remaining
…		…
829		1236
830	The code reference is supposed to return a callback (usually a closure)	1237	The code reference is supposed to return a callback (usually a closure)
831	that works as a plain read callback (see C<< ->push_read ($cb) >>).	1238	that works as a plain read callback (see C<< ->push_read ($cb) >>).
832		1239
833	It should invoke the passed callback when it is done reading (remember to	1240	It should invoke the passed callback when it is done reading (remember to
834	pass C<$self> as first argument as all other callbacks do that).	1241	pass C<$handle> as first argument as all other callbacks do that).
835		1242
836	Note that this is a function, and all types registered this way will be	1243	Note that this is a function, and all types registered this way will be
837	global, so try to use unique names.	1244	global, so try to use unique names.
838		1245
839	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,	1246	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
…		…
842	=item $handle->stop_read	1249	=item $handle->stop_read
843		1250
844	=item $handle->start_read	1251	=item $handle->start_read
845		1252
846	In rare cases you actually do not want to read anything from the	1253	In rare cases you actually do not want to read anything from the
847	socket. In this case you can call C<stop_read>. Neither C<on_read> no	1254	socket. In this case you can call C<stop_read>. Neither C<on_read> nor
848	any queued callbacks will be executed then. To start reading again, call	1255	any queued callbacks will be executed then. To start reading again, call
849	C<start_read>.	1256	C<start_read>.
850		1257
		1258	Note that AnyEvent::Handle will automatically C<start_read> for you when
		1259	you change the C<on_read> callback or push/unshift a read callback, and it
		1260	will automatically C<stop_read> for you when neither C<on_read> is set nor
		1261	there are any read requests in the queue.
		1262
		1263	These methods will have no effect when in TLS mode (as TLS doesn't support
		1264	half-duplex connections).
		1265
851	=cut	1266	=cut
852		1267
853	sub stop_read {	1268	sub stop_read {
854	my ($self) = @_;	1269	my ($self) = @_;
855		1270
856	delete $self->{_rw};	1271	delete $self->{_rw} unless $self->{tls};
857	}	1272	}
858		1273
859	sub start_read {	1274	sub start_read {
860	my ($self) = @_;	1275	my ($self) = @_;
861		1276
862	unless ($self->{_rw} || $self->{_eof}) {	1277	unless ($self->{_rw} || $self->{_eof}) {
863	Scalar::Util::weaken $self;	1278	Scalar::Util::weaken $self;
864		1279
865	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1280	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
866	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1281	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
867	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;	1282	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
868		1283
869	if ($len > 0) {	1284	if ($len > 0) {
870	$self->{filter_r}	1285	$self->{_activity} = AnyEvent->now;
871	? $self->{filter_r}->($self, $rbuf)	1286
872	: $self->_drain_rbuf;	1287	if ($self->{tls}) {
		1288	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
		1289
		1290	&_dotls ($self);
		1291	} else {
		1292	$self->_drain_rbuf unless $self->{_in_drain};
		1293	}
873		1294
874	} elsif (defined $len) {	1295	} elsif (defined $len) {
875	delete $self->{_rw};	1296	delete $self->{_rw};
876	$self->{_eof} = 1;	1297	$self->{_eof} = 1;
877	$self->_drain_rbuf;	1298	$self->_drain_rbuf unless $self->{_in_drain};
878		1299
879	} elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) {	1300	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
880	return $self->error;	1301	return $self->_error ($!, 1);
881	}	1302	}
882	});	1303	});
883	}	1304	}
884	}	1305	}
885		1306
		1307	# poll the write BIO and send the data if applicable
886	sub _dotls {	1308	sub _dotls {
887	my ($self) = @_;	1309	my ($self) = @_;
888		1310
		1311	my $tmp;
		1312
889	if (length $self->{_tls_wbuf}) {	1313	if (length $self->{_tls_wbuf}) {
890	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1314	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
891	substr $self->{_tls_wbuf}, 0, $len, "";	1315	substr $self->{_tls_wbuf}, 0, $tmp, "";
892	}	1316	}
893	}	1317	}
894		1318
		1319	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
		1320	unless (length $tmp) {
		1321	# let's treat SSL-eof as we treat normal EOF
		1322	delete $self->{_rw};
		1323	$self->{_eof} = 1;
		1324	&_freetls;
		1325	}
		1326
		1327	$self->{rbuf} .= $tmp;
		1328	$self->_drain_rbuf unless $self->{_in_drain};
		1329	$self->{tls} or return; # tls session might have gone away in callback
		1330	}
		1331
		1332	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
		1333
		1334	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
		1335	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
		1336	return $self->_error ($!, 1);
		1337	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
		1338	return $self->_error (&Errno::EIO, 1);
		1339	}
		1340
		1341	# all other errors are fine for our purposes
		1342	}
		1343
895	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {	1344	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
896	$self->{wbuf} .= $buf;	1345	$self->{wbuf} .= $tmp;
897	$self->_drain_wbuf;	1346	$self->_drain_wbuf;
898	}
899
900	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
901	$self->{rbuf} .= $buf;
902	$self->_drain_rbuf;
903	}
904
905	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
906
907	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
908	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
909	$self->error;
910	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
911	$! = &Errno::EIO;
912	$self->error;
913	}
914
915	# all others are fine for our purposes
916	}	1347	}
917	}	1348	}
918		1349
919	=item $handle->starttls ($tls[, $tls_ctx])	1350	=item $handle->starttls ($tls[, $tls_ctx])
920		1351
…		…
930		1361
931	The TLS connection object will end up in C<< $handle->{tls} >> after this	1362	The TLS connection object will end up in C<< $handle->{tls} >> after this
932	call and can be used or changed to your liking. Note that the handshake	1363	call and can be used or changed to your liking. Note that the handshake
933	might have already started when this function returns.	1364	might have already started when this function returns.
934		1365
935	=cut	1366	If it an error to start a TLS handshake more than once per
		1367	AnyEvent::Handle object (this is due to bugs in OpenSSL).
936		1368
937	# TODO: maybe document...	1369	=cut
		1370
938	sub starttls {	1371	sub starttls {
939	my ($self, $ssl, $ctx) = @_;	1372	my ($self, $ssl, $ctx) = @_;
940		1373
941	$self->stoptls;	1374	require Net::SSLeay;
942		1375
		1376	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1377	if $self->{tls};
		1378
943	if ($ssl eq "accept") {	1379	if ($ssl eq "accept") {
944	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1380	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
945	Net::SSLeay::set_accept_state ($ssl);	1381	Net::SSLeay::set_accept_state ($ssl);
946	} elsif ($ssl eq "connect") {	1382	} elsif ($ssl eq "connect") {
947	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());	1383	$ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
…		…
953	# basically, this is deep magic (because SSL_read should have the same issues)	1389	# basically, this is deep magic (because SSL_read should have the same issues)
954	# but the openssl maintainers basically said: "trust us, it just works".	1390	# but the openssl maintainers basically said: "trust us, it just works".
955	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1391	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
956	# and mismaintained ssleay-module doesn't even offer them).	1392	# and mismaintained ssleay-module doesn't even offer them).
957	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1393	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1394	#
		1395	# in short: this is a mess.
		1396	#
		1397	# note that we do not try to keep the length constant between writes as we are required to do.
		1398	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1399	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1400	# have identity issues in that area.
958	Net::SSLeay::CTX_set_mode ($self->{tls},	1401	Net::SSLeay::CTX_set_mode ($self->{tls},
959	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)	1402	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
960	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));	1403	| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
961		1404
962	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1405	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
963	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1406	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
964		1407
965	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1408	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
966		1409
967	$self->{filter_w} = sub {	1410	&_dotls; # need to trigger the initial handshake
968	$_[0]{_tls_wbuf} .= ${$_[1]};	1411	$self->start_read; # make sure we actually do read
969	&_dotls;
970	};
971	$self->{filter_r} = sub {
972	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
973	&_dotls;
974	};
975	}	1412	}
976		1413
977	=item $handle->stoptls	1414	=item $handle->stoptls
978		1415
979	Destroys the SSL connection, if any. Partial read or write data will be	1416	Shuts down the SSL connection - this makes a proper EOF handshake by
980	lost.	1417	sending a close notify to the other side, but since OpenSSL doesn't
		1418	support non-blocking shut downs, it is not possible to re-use the stream
		1419	afterwards.
981		1420
982	=cut	1421	=cut
983		1422
984	sub stoptls {	1423	sub stoptls {
985	my ($self) = @_;	1424	my ($self) = @_;
986		1425
		1426	if ($self->{tls}) {
		1427	Net::SSLeay::shutdown ($self->{tls});
		1428
		1429	&_dotls;
		1430
		1431	# we don't give a shit. no, we do, but we can't. no...
		1432	# we, we... have to use openssl :/
		1433	&_freetls;
		1434	}
		1435	}
		1436
		1437	sub _freetls {
		1438	my ($self) = @_;
		1439
		1440	return unless $self->{tls};
		1441
987	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1442	Net::SSLeay::free (delete $self->{tls});
988		1443
989	delete $self->{_rbio};	1444	delete @$self{qw(_rbio _wbio _tls_wbuf)};
990	delete $self->{_wbio};
991	delete $self->{_tls_wbuf};
992	delete $self->{filter_r};
993	delete $self->{filter_w};
994	}	1445	}
995		1446
996	sub DESTROY {	1447	sub DESTROY {
997	my $self = shift;	1448	my $self = shift;
998		1449
999	$self->stoptls;	1450	&_freetls;
		1451
		1452	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
		1453
		1454	if ($linger && length $self->{wbuf}) {
		1455	my $fh = delete $self->{fh};
		1456	my $wbuf = delete $self->{wbuf};
		1457
		1458	my @linger;
		1459
		1460	push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
		1461	my $len = syswrite $fh, $wbuf, length $wbuf;
		1462
		1463	if ($len > 0) {
		1464	substr $wbuf, 0, $len, "";
		1465	} else {
		1466	@linger = (); # end
		1467	}
		1468	});
		1469	push @linger, AnyEvent->timer (after => $linger, cb => sub {
		1470	@linger = ();
		1471	});
		1472	}
		1473	}
		1474
		1475	=item $handle->destroy
		1476
		1477	Shuts down the handle object as much as possible - this call ensures that
		1478	no further callbacks will be invoked and resources will be freed as much
		1479	as possible. You must not call any methods on the object afterwards.
		1480
		1481	Normally, you can just "forget" any references to an AnyEvent::Handle
		1482	object and it will simply shut down. This works in fatal error and EOF
		1483	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1484	callback, so when you want to destroy the AnyEvent::Handle object from
		1485	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1486	that case.
		1487
		1488	The handle might still linger in the background and write out remaining
		1489	data, as specified by the C<linger> option, however.
		1490
		1491	=cut
		1492
		1493	sub destroy {
		1494	my ($self) = @_;
		1495
		1496	$self->DESTROY;
		1497	%$self = ();
1000	}	1498	}
1001		1499
1002	=item AnyEvent::Handle::TLS_CTX	1500	=item AnyEvent::Handle::TLS_CTX
1003		1501
1004	This function creates and returns the Net::SSLeay::CTX object used by	1502	This function creates and returns the Net::SSLeay::CTX object used by
…		…
1034	}	1532	}
1035	}	1533	}
1036		1534
1037	=back	1535	=back
1038		1536
		1537
		1538	=head1 NONFREQUENTLY ASKED QUESTIONS
		1539
		1540	=over 4
		1541
		1542	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1543	still get further invocations!
		1544
		1545	That's because AnyEvent::Handle keeps a reference to itself when handling
		1546	read or write callbacks.
		1547
		1548	It is only safe to "forget" the reference inside EOF or error callbacks,
		1549	from within all other callbacks, you need to explicitly call the C<<
		1550	->destroy >> method.
		1551
		1552	=item I get different callback invocations in TLS mode/Why can't I pause
		1553	reading?
		1554
		1555	Unlike, say, TCP, TLS connections do not consist of two independent
		1556	communication channels, one for each direction. Or put differently. The
		1557	read and write directions are not independent of each other: you cannot
		1558	write data unless you are also prepared to read, and vice versa.
		1559
		1560	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1561	callback invocations when you are not expecting any read data - the reason
		1562	is that AnyEvent::Handle always reads in TLS mode.
		1563
		1564	During the connection, you have to make sure that you always have a
		1565	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1566	connection (or when you no longer want to use it) you can call the
		1567	C<destroy> method.
		1568
		1569	=item How do I read data until the other side closes the connection?
		1570
		1571	If you just want to read your data into a perl scalar, the easiest way
		1572	to achieve this is by setting an C<on_read> callback that does nothing,
		1573	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1574	will be in C<$_[0]{rbuf}>:
		1575
		1576	$handle->on_read (sub { });
		1577	$handle->on_eof (undef);
		1578	$handle->on_error (sub {
		1579	my $data = delete $_[0]{rbuf};
		1580	undef $handle;
		1581	});
		1582
		1583	The reason to use C<on_error> is that TCP connections, due to latencies
		1584	and packets loss, might get closed quite violently with an error, when in
		1585	fact, all data has been received.
		1586
		1587	It is usually better to use acknowledgements when transferring data,
		1588	to make sure the other side hasn't just died and you got the data
		1589	intact. This is also one reason why so many internet protocols have an
		1590	explicit QUIT command.
		1591
		1592	=item I don't want to destroy the handle too early - how do I wait until
		1593	all data has been written?
		1594
		1595	After writing your last bits of data, set the C<on_drain> callback
		1596	and destroy the handle in there - with the default setting of
		1597	C<low_water_mark> this will be called precisely when all data has been
		1598	written to the socket:
		1599
		1600	$handle->push_write (...);
		1601	$handle->on_drain (sub {
		1602	warn "all data submitted to the kernel\n";
		1603	undef $handle;
		1604	});
		1605
		1606	=back
		1607
		1608
1039	=head1 SUBCLASSING AnyEvent::Handle	1609	=head1 SUBCLASSING AnyEvent::Handle
1040		1610
1041	In many cases, you might want to subclass AnyEvent::Handle.	1611	In many cases, you might want to subclass AnyEvent::Handle.
1042		1612
1043	To make this easier, a given version of AnyEvent::Handle uses these	1613	To make this easier, a given version of AnyEvent::Handle uses these
…		…
1046	=over 4	1616	=over 4
1047		1617
1048	=item * all constructor arguments become object members.	1618	=item * all constructor arguments become object members.
1049		1619
1050	At least initially, when you pass a C<tls>-argument to the constructor it	1620	At least initially, when you pass a C<tls>-argument to the constructor it
1051	will end up in C<< $handle->{tls} >>. Those members might be changes or	1621	will end up in C<< $handle->{tls} >>. Those members might be changed or
1052	mutated later on (for example C<tls> will hold the TLS connection object).	1622	mutated later on (for example C<tls> will hold the TLS connection object).
1053		1623
1054	=item * other object member names are prefixed with an C<_>.	1624	=item * other object member names are prefixed with an C<_>.
1055		1625
1056	All object members not explicitly documented (internal use) are prefixed	1626	All object members not explicitly documented (internal use) are prefixed

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