[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent/Handle.pm

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.79 by root, Sun Jul 27 08:37:56 2008 UTC vs.
Revision 1.117 by root, Tue Feb 10 14:22:59 2009 UTC

…		…
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 = 4.22;	19	our $VERSION = 4.331;
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
…		…
27		27
28	my $handle =	28	my $handle =
29	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
30	fh => \*STDIN,	30	fh => \*STDIN,
31	on_eof => sub {	31	on_eof => sub {
32	$cv->broadcast;	32	$cv->send;
33	},	33	},
34	);	34	);
35		35
36	# send some request line	36	# send some request line
37	$handle->push_write ("getinfo\015\012");	37	$handle->push_write ("getinfo\015\012");
…		…
49		49
50	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
52	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
53		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
54	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
55	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
56	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
57		60
58	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
…		…
70		73
71	=item fh => $filehandle [MANDATORY]	74	=item fh => $filehandle [MANDATORY]
72		75
73	The filehandle this L<AnyEvent::Handle> object will operate on.	76	The filehandle this L<AnyEvent::Handle> object will operate on.
74		77
75	NOTE: The filehandle will be set to non-blocking (using	78	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	79	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		80	that mode.
77		81
78	=item on_eof => $cb->($handle)	82	=item on_eof => $cb->($handle)
79		83
80	Set the callback to be called when an end-of-file condition is detected,	84	Set the callback to be called when an end-of-file condition is detected,
81	i.e. in the case of a socket, when the other side has closed the	85	i.e. in the case of a socket, when the other side has closed the
82	connection cleanly.	86	connection cleanly.
83		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
84	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,
85	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
86	waiting for data.	95	waiting for data.
		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>.
87		99
88	=item on_error => $cb->($handle, $fatal)	100	=item on_error => $cb->($handle, $fatal)
89		101
90	This is the error callback, which is called when, well, some error	102	This is the error callback, which is called when, well, some error
91	occured, such as not being able to resolve the hostname, failure to	103	occured, such as not being able to resolve the hostname, failure to
92	connect or a read error.	104	connect or a read error.
93		105
94	Some errors are fatal (which is indicated by C<$fatal> being true). On	106	Some errors are fatal (which is indicated by C<$fatal> being true). On
95	fatal errors the handle object will be shut down and will not be	107	fatal errors the handle object will be shut down and will not be usable
		108	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		109	errors are an EOF condition with active (but unsatisifable) read watchers
		110	(C<EPIPE>) or I/O errors.
		111
96	usable. Non-fatal errors can be retried by simply returning, but it is	112	Non-fatal errors can be retried by simply returning, but it is recommended
97	recommended to simply ignore this parameter and instead abondon the handle	113	to simply ignore this parameter and instead abondon the handle object
98	object when this callback is invoked.	114	when this callback is invoked. Examples of non-fatal errors are timeouts
		115	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99		116
100	On callback entrance, the value of C<$!> contains the operating system	117	On callback entrance, the value of C<$!> contains the operating system
101	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).	118	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
102		119
103	While not mandatory, it is I<highly> recommended to set this callback, as	120	While not mandatory, it is I<highly> recommended to set this callback, as
…		…
110	and no read request is in the queue (unlike read queue callbacks, this	127	and no read request is in the queue (unlike read queue callbacks, this
111	callback will only be called when at least one octet of data is in the	128	callback will only be called when at least one octet of data is in the
112	read buffer).	129	read buffer).
113		130
114	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	131	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
115	method or access the C<$handle->{rbuf}> member directly.	132	method or access the C<$handle->{rbuf}> member directly. Note that you
		133	must not enlarge or modify the read buffer, you can only remove data at
		134	the beginning from it.
116		135
117	When an EOF condition is detected then AnyEvent::Handle will first try to	136	When an EOF condition is detected then AnyEvent::Handle will first try to
118	feed all the remaining data to the queued callbacks and C<on_read> before	137	feed all the remaining data to the queued callbacks and C<on_read> before
119	calling the C<on_eof> callback. If no progress can be made, then a fatal	138	calling the C<on_eof> callback. If no progress can be made, then a fatal
120	error will be raised (with C<$!> set to C<EPIPE>).	139	error will be raised (with C<$!> set to C<EPIPE>).
…		…
135	=item timeout => $fractional_seconds	154	=item timeout => $fractional_seconds
136		155
137	If non-zero, then this enables an "inactivity" timeout: whenever this many	156	If non-zero, then this enables an "inactivity" timeout: whenever this many
138	seconds pass without a successful read or write on the underlying file	157	seconds pass without a successful read or write on the underlying file
139	handle, the C<on_timeout> callback will be invoked (and if that one is	158	handle, the C<on_timeout> callback will be invoked (and if that one is
140	missing, an C<ETIMEDOUT> error will be raised).	159	missing, a non-fatal C<ETIMEDOUT> error will be raised).
141		160
142	Note that timeout processing is also active when you currently do not have	161	Note that timeout processing is also active when you currently do not have
143	any outstanding read or write requests: If you plan to keep the connection	162	any outstanding read or write requests: If you plan to keep the connection
144	idle then you should disable the timout temporarily or ignore the timeout	163	idle then you should disable the timout temporarily or ignore the timeout
145	in the C<on_timeout> callback.	164	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		165	restart the timeout.
146		166
147	Zero (the default) disables this timeout.	167	Zero (the default) disables this timeout.
148		168
149	=item on_timeout => $cb->($handle)	169	=item on_timeout => $cb->($handle)
150		170
…		…
154		174
155	=item rbuf_max => <bytes>	175	=item rbuf_max => <bytes>
156		176
157	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	177	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
158	when the read buffer ever (strictly) exceeds this size. This is useful to	178	when the read buffer ever (strictly) exceeds this size. This is useful to
159	avoid denial-of-service attacks.	179	avoid some forms of denial-of-service attacks.
160		180
161	For example, a server accepting connections from untrusted sources should	181	For example, a server accepting connections from untrusted sources should
162	be configured to accept only so-and-so much data that it cannot act on	182	be configured to accept only so-and-so much data that it cannot act on
163	(for example, when expecting a line, an attacker could send an unlimited	183	(for example, when expecting a line, an attacker could send an unlimited
164	amount of data without a callback ever being called as long as the line	184	amount of data without a callback ever being called as long as the line
165	isn't finished).	185	isn't finished).
166		186
167	=item autocork => <boolean>	187	=item autocork => <boolean>
168		188
169	When disabled (the default), then C<push_write> will try to immediately	189	When disabled (the default), then C<push_write> will try to immediately
170	write the data to the handle if possible. This avoids having to register	190	write the data to the handle, if possible. This avoids having to register
171	a write watcher and wait for the next event loop iteration, but can be	191	a write watcher and wait for the next event loop iteration, but can
172	inefficient if you write multiple small chunks (this disadvantage is	192	be inefficient if you write multiple small chunks (on the wire, this
173	usually avoided by your kernel's nagle algorithm, see C<low_delay>).	193	disadvantage is usually avoided by your kernel's nagle algorithm, see
		194	C<no_delay>, but this option can save costly syscalls).
174		195
175	When enabled, then writes will always be queued till the next event loop	196	When enabled, then writes will always be queued till the next event loop
176	iteration. This is efficient when you do many small writes per iteration,	197	iteration. This is efficient when you do many small writes per iteration,
177	but less efficient when you do a single write only.	198	but less efficient when you do a single write only per iteration (or when
		199	the write buffer often is full). It also increases write latency.
178		200
179	=item no_delay => <boolean>	201	=item no_delay => <boolean>
180		202
181	When doing small writes on sockets, your operating system kernel might	203	When doing small writes on sockets, your operating system kernel might
182	wait a bit for more data before actually sending it out. This is called	204	wait a bit for more data before actually sending it out. This is called
183	the Nagle algorithm, and usually it is beneficial.	205	the Nagle algorithm, and usually it is beneficial.
184		206
185	In some situations you want as low a delay as possible, which cna be	207	In some situations you want as low a delay as possible, which can be
186	accomplishd by setting this option to true.	208	accomplishd by setting this option to a true value.
187		209
188	The default is your opertaing system's default behaviour, this option	210	The default is your opertaing system's default behaviour (most likely
189	explicitly enables or disables it, if possible.	211	enabled), this option explicitly enables or disables it, if possible.
190		212
191	=item read_size => <bytes>	213	=item read_size => <bytes>
192		214
193	The default read block size (the amount of bytes this module will try to read	215	The default read block size (the amount of bytes this module will
194	during each (loop iteration). Default: C<8192>.	216	try to read during each loop iteration, which affects memory
		217	requirements). Default: C<8192>.
195		218
196	=item low_water_mark => <bytes>	219	=item low_water_mark => <bytes>
197		220
198	Sets the amount of bytes (default: C<0>) that make up an "empty" write	221	Sets the amount of bytes (default: C<0>) that make up an "empty" write
199	buffer: If the write reaches this size or gets even samller it is	222	buffer: If the write reaches this size or gets even samller it is
200	considered empty.	223	considered empty.
201		224
		225	Sometimes it can be beneficial (for performance reasons) to add data to
		226	the write buffer before it is fully drained, but this is a rare case, as
		227	the operating system kernel usually buffers data as well, so the default
		228	is good in almost all cases.
		229
202	=item linger => <seconds>	230	=item linger => <seconds>
203		231
204	If non-zero (default: C<3600>), then the destructor of the	232	If non-zero (default: C<3600>), then the destructor of the
205	AnyEvent::Handle object will check wether there is still outstanding write	233	AnyEvent::Handle object will check whether there is still outstanding
206	data and will install a watcher that will write out this data. No errors	234	write data and will install a watcher that will write this data to the
207	will be reported (this mostly matches how the operating system treats	235	socket. No errors will be reported (this mostly matches how the operating
208	outstanding data at socket close time).	236	system treats outstanding data at socket close time).
209		237
210	This will not work for partial TLS data that could not yet been	238	This will not work for partial TLS data that could not be encoded
211	encoded. This data will be lost.	239	yet. This data will be lost. Calling the C<stoptls> method in time might
		240	help.
212		241
213	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object	242	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object
214		243
215	When this parameter is given, it enables TLS (SSL) mode, that means it	244	When this parameter is given, it enables TLS (SSL) mode, that means
216	will start making tls handshake and will transparently encrypt/decrypt	245	AnyEvent will start a TLS handshake as soon as the conenction has been
217	data.	246	established and will transparently encrypt/decrypt data afterwards.
218		247
219	TLS mode requires Net::SSLeay to be installed (it will be loaded	248	TLS mode requires Net::SSLeay to be installed (it will be loaded
220	automatically when you try to create a TLS handle).	249	automatically when you try to create a TLS handle): this module doesn't
		250	have a dependency on that module, so if your module requires it, you have
		251	to add the dependency yourself.
221		252
222	For the TLS server side, use C<accept>, and for the TLS client side of a	253	Unlike TCP, TLS has a server and client side: for the TLS server side, use
223	connection, use C<connect> mode.	254	C<accept>, and for the TLS client side of a connection, use C<connect>
		255	mode.
224		256
225	You can also provide your own TLS connection object, but you have	257	You can also provide your own TLS connection object, but you have
226	to make sure that you call either C<Net::SSLeay::set_connect_state>	258	to make sure that you call either C<Net::SSLeay::set_connect_state>
227	or C<Net::SSLeay::set_accept_state> on it before you pass it to	259	or C<Net::SSLeay::set_accept_state> on it before you pass it to
228	AnyEvent::Handle.	260	AnyEvent::Handle.
229		261
		262	B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
		263	passing in the wrong integer will lead to certain crash. This most often
		264	happens when one uses a stylish C<< tls => 1 >> and is surprised about the
		265	segmentation fault.
		266
230	See the C<starttls> method if you need to start TLS negotiation later.	267	See the C<< ->starttls >> method for when need to start TLS negotiation later.
231		268
232	=item tls_ctx => $ssl_ctx	269	=item tls_ctx => $ssl_ctx
233		270
234	Use the given Net::SSLeay::CTX object to create the new TLS connection	271	Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
235	(unless a connection object was specified directly). If this parameter is	272	(unless a connection object was specified directly). If this parameter is
236	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	273	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
237		274
238	=item json => JSON or JSON::XS object	275	=item json => JSON or JSON::XS object
239		276
240	This is the json coder object used by the C<json> read and write types.	277	This is the json coder object used by the C<json> read and write types.
241		278
242	If you don't supply it, then AnyEvent::Handle will create and use a	279	If you don't supply it, then AnyEvent::Handle will create and use a
243	suitable one, which will write and expect UTF-8 encoded JSON texts.	280	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		281	texts.
244		282
245	Note that you are responsible to depend on the JSON module if you want to	283	Note that you are responsible to depend on the JSON module if you want to
246	use this functionality, as AnyEvent does not have a dependency itself.	284	use this functionality, as AnyEvent does not have a dependency itself.
247		285
248	=item filter_r => $cb
249
250	=item filter_w => $cb
251
252	These exist, but are undocumented at this time.
253
254	=back	286	=back
255		287
256	=cut	288	=cut
257		289
258	sub new {	290	sub new {
…		…
262		294
263	$self->{fh} or Carp::croak "mandatory argument fh is missing";	295	$self->{fh} or Carp::croak "mandatory argument fh is missing";
264		296
265	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	297	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
266		298
267	if ($self->{tls}) {
268	require Net::SSLeay;
269	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	299	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
270	}	300	if $self->{tls};
271		301
272	$self->{_activity} = AnyEvent->now;	302	$self->{_activity} = AnyEvent->now;
273	$self->_timeout;	303	$self->_timeout;
274		304
275	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};	305	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
…		…
287	delete $self->{_tw};	317	delete $self->{_tw};
288	delete $self->{_rw};	318	delete $self->{_rw};
289	delete $self->{_ww};	319	delete $self->{_ww};
290	delete $self->{fh};	320	delete $self->{fh};
291		321
292	$self->stoptls;	322	&_freetls;
		323
		324	delete $self->{on_read};
		325	delete $self->{_queue};
293	}	326	}
294		327
295	sub _error {	328	sub _error {
296	my ($self, $errno, $fatal) = @_;	329	my ($self, $errno, $fatal) = @_;
297		330
…		…
300		333
301	$! = $errno;	334	$! = $errno;
302		335
303	if ($self->{on_error}) {	336	if ($self->{on_error}) {
304	$self->{on_error}($self, $fatal);	337	$self->{on_error}($self, $fatal);
305	} else {	338	} elsif ($self->{fh}) {
306	Carp::croak "AnyEvent::Handle uncaught error: $!";	339	Carp::croak "AnyEvent::Handle uncaught error: $!";
307	}	340	}
308	}	341	}
309		342
310	=item $fh = $handle->fh	343	=item $fh = $handle->fh
311		344
312	This method returns the file handle of the L<AnyEvent::Handle> object.	345	This method returns the file handle used to create the L<AnyEvent::Handle> object.
313		346
314	=cut	347	=cut
315		348
316	sub fh { $_[0]{fh} }	349	sub fh { $_[0]{fh} }
317		350
…		…
335	$_[0]{on_eof} = $_[1];	368	$_[0]{on_eof} = $_[1];
336	}	369	}
337		370
338	=item $handle->on_timeout ($cb)	371	=item $handle->on_timeout ($cb)
339		372
340	Replace the current C<on_timeout> callback, or disables the callback	373	Replace the current C<on_timeout> callback, or disables the callback (but
341	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor	374	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
342	argument.	375	argument and method.
343		376
344	=cut	377	=cut
345		378
346	sub on_timeout {	379	sub on_timeout {
347	$_[0]{on_timeout} = $_[1];	380	$_[0]{on_timeout} = $_[1];
348	}	381	}
349		382
350	=item $handle->autocork ($boolean)	383	=item $handle->autocork ($boolean)
351		384
352	Enables or disables the current autocork behaviour (see C<autocork>	385	Enables or disables the current autocork behaviour (see C<autocork>
353	constructor argument).	386	constructor argument). Changes will only take effect on the next write.
354		387
355	=cut	388	=cut
		389
		390	sub autocork {
		391	$_[0]{autocork} = $_[1];
		392	}
356		393
357	=item $handle->no_delay ($boolean)	394	=item $handle->no_delay ($boolean)
358		395
359	Enables or disables the C<no_delay> setting (see constructor argument of	396	Enables or disables the C<no_delay> setting (see constructor argument of
360	the same name for details).	397	the same name for details).
…		…
453	my ($self, $cb) = @_;	490	my ($self, $cb) = @_;
454		491
455	$self->{on_drain} = $cb;	492	$self->{on_drain} = $cb;
456		493
457	$cb->($self)	494	$cb->($self)
458	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	495	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
459	}	496	}
460		497
461	=item $handle->push_write ($data)	498	=item $handle->push_write ($data)
462		499
463	Queues the given scalar to be written. You can push as much data as you	500	Queues the given scalar to be written. You can push as much data as you
…		…
480	substr $self->{wbuf}, 0, $len, "";	517	substr $self->{wbuf}, 0, $len, "";
481		518
482	$self->{_activity} = AnyEvent->now;	519	$self->{_activity} = AnyEvent->now;
483		520
484	$self->{on_drain}($self)	521	$self->{on_drain}($self)
485	if $self->{low_water_mark} >= length $self->{wbuf}	522	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
486	&& $self->{on_drain};	523	&& $self->{on_drain};
487		524
488	delete $self->{_ww} unless length $self->{wbuf};	525	delete $self->{_ww} unless length $self->{wbuf};
489	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	526	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
490	$self->_error ($!, 1);	527	$self->_error ($!, 1);
…		…
514		551
515	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	552	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
516	->($self, @_);	553	->($self, @_);
517	}	554	}
518		555
519	if ($self->{filter_w}) {	556	if ($self->{tls}) {
520	$self->{filter_w}($self, \$_[0]);	557	$self->{_tls_wbuf} .= $_[0];
		558
		559	&_dotls ($self);
521	} else {	560	} else {
522	$self->{wbuf} .= $_[0];	561	$self->{wbuf} .= $_[0];
523	$self->_drain_wbuf;	562	$self->_drain_wbuf;
524	}	563	}
525	}	564	}
…		…
542	=cut	581	=cut
543		582
544	register_write_type netstring => sub {	583	register_write_type netstring => sub {
545	my ($self, $string) = @_;	584	my ($self, $string) = @_;
546		585
547	sprintf "%d:%s,", (length $string), $string	586	(length $string) . ":$string,"
548	};	587	};
549		588
550	=item packstring => $format, $data	589	=item packstring => $format, $data
551		590
552	An octet string prefixed with an encoded length. The encoding C<$format>	591	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
726		765
727	if (	766	if (
728	defined $self->{rbuf_max}	767	defined $self->{rbuf_max}
729	&& $self->{rbuf_max} < length $self->{rbuf}	768	&& $self->{rbuf_max} < length $self->{rbuf}
730	) {	769	) {
731	return $self->_error (&Errno::ENOSPC, 1);	770	$self->_error (&Errno::ENOSPC, 1), return;
732	}	771	}
733		772
734	while () {	773	while () {
		774	# we need to use a separate tls read buffer, as we must not receive data while
		775	# we are draining the buffer, and this can only happen with TLS.
		776	$self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
		777
735	my $len = length $self->{rbuf};	778	my $len = length $self->{rbuf};
736		779
737	if (my $cb = shift @{ $self->{_queue} }) {	780	if (my $cb = shift @{ $self->{_queue} }) {
738	unless ($cb->($self)) {	781	unless ($cb->($self)) {
739	if ($self->{_eof}) {	782	if ($self->{_eof}) {
740	# no progress can be made (not enough data and no data forthcoming)	783	# no progress can be made (not enough data and no data forthcoming)
741	$self->_error (&Errno::EPIPE, 1), last;	784	$self->_error (&Errno::EPIPE, 1), return;
742	}	785	}
743		786
744	unshift @{ $self->{_queue} }, $cb;	787	unshift @{ $self->{_queue} }, $cb;
745	last;	788	last;
746	}	789	}
…		…
754	&& !@{ $self->{_queue} } # and the queue is still empty	797	&& !@{ $self->{_queue} } # and the queue is still empty
755	&& $self->{on_read} # but we still have on_read	798	&& $self->{on_read} # but we still have on_read
756	) {	799	) {
757	# no further data will arrive	800	# no further data will arrive
758	# so no progress can be made	801	# so no progress can be made
759	$self->_error (&Errno::EPIPE, 1), last	802	$self->_error (&Errno::EPIPE, 1), return
760	if $self->{_eof};	803	if $self->{_eof};
761		804
762	last; # more data might arrive	805	last; # more data might arrive
763	}	806	}
764	} else {	807	} else {
765	# read side becomes idle	808	# read side becomes idle
766	delete $self->{_rw};	809	delete $self->{_rw} unless $self->{tls};
767	last;	810	last;
768	}	811	}
769	}	812	}
770		813
		814	if ($self->{_eof}) {
		815	if ($self->{on_eof}) {
771	$self->{on_eof}($self)	816	$self->{on_eof}($self)
772	if $self->{_eof} && $self->{on_eof};	817	} else {
		818	$self->_error (0, 1);
		819	}
		820	}
773		821
774	# may need to restart read watcher	822	# may need to restart read watcher
775	unless ($self->{_rw}) {	823	unless ($self->{_rw}) {
776	$self->start_read	824	$self->start_read
777	if $self->{on_read} \|\| @{ $self->{_queue} };	825	if $self->{on_read} \|\| @{ $self->{_queue} };
…		…
795		843
796	=item $handle->rbuf	844	=item $handle->rbuf
797		845
798	Returns the read buffer (as a modifiable lvalue).	846	Returns the read buffer (as a modifiable lvalue).
799		847
800	You can access the read buffer directly as the C<< ->{rbuf} >> member, if	848	You can access the read buffer directly as the C<< ->{rbuf} >>
801	you want.	849	member, if you want. However, the only operation allowed on the
		850	read buffer (apart from looking at it) is removing data from its
		851	beginning. Otherwise modifying or appending to it is not allowed and will
		852	lead to hard-to-track-down bugs.
802		853
803	NOTE: The read buffer should only be used or modified if the C<on_read>,	854	NOTE: The read buffer should only be used or modified if the C<on_read>,
804	C<push_read> or C<unshift_read> methods are used. The other read methods	855	C<push_read> or C<unshift_read> methods are used. The other read methods
805	automatically manage the read buffer.	856	automatically manage the read buffer.
806		857
…		…
1061	An octet string prefixed with an encoded length. The encoding C<$format>	1112	An octet string prefixed with an encoded length. The encoding C<$format>
1062	uses the same format as a Perl C<pack> format, but must specify a single	1113	uses the same format as a Perl C<pack> format, but must specify a single
1063	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an	1114	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1064	optional C<!>, C<< < >> or C<< > >> modifier).	1115	optional C<!>, C<< < >> or C<< > >> modifier).
1065		1116
1066	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.	1117	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1118	EPP uses a prefix of C<N> (4 octtes).
1067		1119
1068	Example: read a block of data prefixed by its length in BER-encoded	1120	Example: read a block of data prefixed by its length in BER-encoded
1069	format (very efficient).	1121	format (very efficient).
1070		1122
1071	$handle->push_read (packstring => "w", sub {	1123	$handle->push_read (packstring => "w", sub {
…		…
1101	}	1153	}
1102	};	1154	};
1103		1155
1104	=item json => $cb->($handle, $hash_or_arrayref)	1156	=item json => $cb->($handle, $hash_or_arrayref)
1105		1157
1106	Reads a JSON object or array, decodes it and passes it to the callback.	1158	Reads a JSON object or array, decodes it and passes it to the
		1159	callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1107		1160
1108	If a C<json> object was passed to the constructor, then that will be used	1161	If a C<json> object was passed to the constructor, then that will be used
1109	for the final decode, otherwise it will create a JSON coder expecting UTF-8.	1162	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1110		1163
1111	This read type uses the incremental parser available with JSON version	1164	This read type uses the incremental parser available with JSON version
…		…
1128	my $rbuf = \$self->{rbuf};	1181	my $rbuf = \$self->{rbuf};
1129		1182
1130	my $json = $self->{json} \|\|= JSON->new->utf8;	1183	my $json = $self->{json} \|\|= JSON->new->utf8;
1131		1184
1132	sub {	1185	sub {
1133	my $ref = $json->incr_parse ($self->{rbuf});	1186	my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1134		1187
1135	if ($ref) {	1188	if ($ref) {
1136	$self->{rbuf} = $json->incr_text;	1189	$self->{rbuf} = $json->incr_text;
1137	$json->incr_text = "";	1190	$json->incr_text = "";
1138	$cb->($self, $ref);	1191	$cb->($self, $ref);
1139		1192
1140	1	1193	1
		1194	} elsif ($@) {
		1195	# error case
		1196	$json->incr_skip;
		1197
		1198	$self->{rbuf} = $json->incr_text;
		1199	$json->incr_text = "";
		1200
		1201	$self->_error (&Errno::EBADMSG);
		1202
		1203	()
1141	} else {	1204	} else {
1142	$self->{rbuf} = "";	1205	$self->{rbuf} = "";
		1206
1143	()	1207	()
1144	}	1208	}
1145	}	1209	}
1146	};	1210	};
1147		1211
…		…
1224	Note that AnyEvent::Handle will automatically C<start_read> for you when	1288	Note that AnyEvent::Handle will automatically C<start_read> for you when
1225	you change the C<on_read> callback or push/unshift a read callback, and it	1289	you change the C<on_read> callback or push/unshift a read callback, and it
1226	will automatically C<stop_read> for you when neither C<on_read> is set nor	1290	will automatically C<stop_read> for you when neither C<on_read> is set nor
1227	there are any read requests in the queue.	1291	there are any read requests in the queue.
1228		1292
		1293	These methods will have no effect when in TLS mode (as TLS doesn't support
		1294	half-duplex connections).
		1295
1229	=cut	1296	=cut
1230		1297
1231	sub stop_read {	1298	sub stop_read {
1232	my ($self) = @_;	1299	my ($self) = @_;
1233		1300
1234	delete $self->{_rw};	1301	delete $self->{_rw} unless $self->{tls};
1235	}	1302	}
1236		1303
1237	sub start_read {	1304	sub start_read {
1238	my ($self) = @_;	1305	my ($self) = @_;
1239		1306
1240	unless ($self->{_rw} \|\| $self->{_eof}) {	1307	unless ($self->{_rw} \|\| $self->{_eof}) {
1241	Scalar::Util::weaken $self;	1308	Scalar::Util::weaken $self;
1242		1309
1243	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1310	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1244	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1311	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1245	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;	1312	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;
1246		1313
1247	if ($len > 0) {	1314	if ($len > 0) {
1248	$self->{_activity} = AnyEvent->now;	1315	$self->{_activity} = AnyEvent->now;
1249		1316
1250	$self->{filter_r}	1317	if ($self->{tls}) {
1251	? $self->{filter_r}($self, $rbuf)	1318	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1252	: $self->{_in_drain} \|\| $self->_drain_rbuf;	1319
		1320	&_dotls ($self);
		1321	} else {
		1322	$self->_drain_rbuf unless $self->{_in_drain};
		1323	}
1253		1324
1254	} elsif (defined $len) {	1325	} elsif (defined $len) {
1255	delete $self->{_rw};	1326	delete $self->{_rw};
1256	$self->{_eof} = 1;	1327	$self->{_eof} = 1;
1257	$self->_drain_rbuf unless $self->{_in_drain};	1328	$self->_drain_rbuf unless $self->{_in_drain};
…		…
1261	}	1332	}
1262	});	1333	});
1263	}	1334	}
1264	}	1335	}
1265		1336
		1337	# poll the write BIO and send the data if applicable
1266	sub _dotls {	1338	sub _dotls {
1267	my ($self) = @_;	1339	my ($self) = @_;
1268		1340
1269	my $buf;	1341	my $tmp;
1270		1342
1271	if (length $self->{_tls_wbuf}) {	1343	if (length $self->{_tls_wbuf}) {
1272	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1344	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1273	substr $self->{_tls_wbuf}, 0, $len, "";	1345	substr $self->{_tls_wbuf}, 0, $tmp, "";
1274	}	1346	}
1275	}	1347	}
1276		1348
1277	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1278	$self->{wbuf} .= $buf;
1279	$self->_drain_wbuf;
1280	}
1281
1282	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1349	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1283	if (length $buf) {	1350	unless (length $tmp) {
1284	$self->{rbuf} .= $buf;
1285	$self->_drain_rbuf unless $self->{_in_drain};
1286	} else {
1287	# let's treat SSL-eof as we treat normal EOF	1351	# let's treat SSL-eof as we treat normal EOF
		1352	delete $self->{_rw};
1288	$self->{_eof} = 1;	1353	$self->{_eof} = 1;
1289	$self->_shutdown;	1354	&_freetls;
1290	return;
1291	}	1355	}
1292	}
1293		1356
		1357	$self->{_tls_rbuf} .= $tmp;
		1358	$self->_drain_rbuf unless $self->{_in_drain};
		1359	$self->{tls} or return; # tls session might have gone away in callback
		1360	}
		1361
1294	my $err = Net::SSLeay::get_error ($self->{tls}, -1);	1362	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1295		1363
1296	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {	1364	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1297	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {	1365	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1298	return $self->_error ($!, 1);	1366	return $self->_error ($!, 1);
1299	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1367	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1300	return $self->_error (&Errno::EIO, 1);	1368	return $self->_error (&Errno::EIO, 1);
1301	}	1369	}
1302		1370
1303	# all others are fine for our purposes	1371	# all other errors are fine for our purposes
		1372	}
		1373
		1374	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1375	$self->{wbuf} .= $tmp;
		1376	$self->_drain_wbuf;
1304	}	1377	}
1305	}	1378	}
1306		1379
1307	=item $handle->starttls ($tls[, $tls_ctx])	1380	=item $handle->starttls ($tls[, $tls_ctx])
1308		1381
…		…
1318		1391
1319	The TLS connection object will end up in C<< $handle->{tls} >> after this	1392	The TLS connection object will end up in C<< $handle->{tls} >> after this
1320	call and can be used or changed to your liking. Note that the handshake	1393	call and can be used or changed to your liking. Note that the handshake
1321	might have already started when this function returns.	1394	might have already started when this function returns.
1322		1395
		1396	If it an error to start a TLS handshake more than once per
		1397	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1398
1323	=cut	1399	=cut
1324		1400
1325	sub starttls {	1401	sub starttls {
1326	my ($self, $ssl, $ctx) = @_;	1402	my ($self, $ssl, $ctx) = @_;
1327		1403
1328	$self->stoptls;	1404	require Net::SSLeay;
1329		1405
		1406	Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
		1407	if $self->{tls};
		1408
1330	if ($ssl eq "accept") {	1409	if ($ssl eq "accept") {
1331	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1410	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
1332	Net::SSLeay::set_accept_state ($ssl);	1411	Net::SSLeay::set_accept_state ($ssl);
1333	} elsif ($ssl eq "connect") {	1412	} elsif ($ssl eq "connect") {
1334	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1413	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
…		…
1340	# basically, this is deep magic (because SSL_read should have the same issues)	1419	# basically, this is deep magic (because SSL_read should have the same issues)
1341	# but the openssl maintainers basically said: "trust us, it just works".	1420	# but the openssl maintainers basically said: "trust us, it just works".
1342	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1421	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1343	# and mismaintained ssleay-module doesn't even offer them).	1422	# and mismaintained ssleay-module doesn't even offer them).
1344	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1423	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1424	#
		1425	# in short: this is a mess.
		1426	#
		1427	# note that we do not try to keep the length constant between writes as we are required to do.
		1428	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1429	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1430	# have identity issues in that area.
1345	Net::SSLeay::CTX_set_mode ($self->{tls},	1431	Net::SSLeay::CTX_set_mode ($self->{tls},
1346	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)	1432	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)
1347	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));	1433	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));
1348		1434
1349	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1435	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1350	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1436	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1351		1437
1352	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1438	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1353		1439
1354	$self->{filter_w} = sub {	1440	&_dotls; # need to trigger the initial handshake
1355	$_[0]{_tls_wbuf} .= ${$_[1]};	1441	$self->start_read; # make sure we actually do read
1356	&_dotls;
1357	};
1358	$self->{filter_r} = sub {
1359	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1360	&_dotls;
1361	};
1362	}	1442	}
1363		1443
1364	=item $handle->stoptls	1444	=item $handle->stoptls
1365		1445
1366	Destroys the SSL connection, if any. Partial read or write data will be	1446	Shuts down the SSL connection - this makes a proper EOF handshake by
1367	lost.	1447	sending a close notify to the other side, but since OpenSSL doesn't
		1448	support non-blocking shut downs, it is not possible to re-use the stream
		1449	afterwards.
1368		1450
1369	=cut	1451	=cut
1370		1452
1371	sub stoptls {	1453	sub stoptls {
1372	my ($self) = @_;	1454	my ($self) = @_;
1373		1455
		1456	if ($self->{tls}) {
		1457	Net::SSLeay::shutdown ($self->{tls});
		1458
		1459	&_dotls;
		1460
		1461	# we don't give a shit. no, we do, but we can't. no...
		1462	# we, we... have to use openssl :/
		1463	&_freetls;
		1464	}
		1465	}
		1466
		1467	sub _freetls {
		1468	my ($self) = @_;
		1469
		1470	return unless $self->{tls};
		1471
1374	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1472	Net::SSLeay::free (delete $self->{tls});
1375		1473
1376	delete $self->{_rbio};	1474	delete @$self{qw(_rbio _wbio _tls_wbuf)};
1377	delete $self->{_wbio};
1378	delete $self->{_tls_wbuf};
1379	delete $self->{filter_r};
1380	delete $self->{filter_w};
1381	}	1475	}
1382		1476
1383	sub DESTROY {	1477	sub DESTROY {
1384	my $self = shift;	1478	my $self = shift;
1385		1479
1386	$self->stoptls;	1480	&_freetls;
1387		1481
1388	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	1482	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1389		1483
1390	if ($linger && length $self->{wbuf}) {	1484	if ($linger && length $self->{wbuf}) {
1391	my $fh = delete $self->{fh};	1485	my $fh = delete $self->{fh};
…		…
1406	@linger = ();	1500	@linger = ();
1407	});	1501	});
1408	}	1502	}
1409	}	1503	}
1410		1504
		1505	=item $handle->destroy
		1506
		1507	Shuts down the handle object as much as possible - this call ensures that
		1508	no further callbacks will be invoked and resources will be freed as much
		1509	as possible. You must not call any methods on the object afterwards.
		1510
		1511	Normally, you can just "forget" any references to an AnyEvent::Handle
		1512	object and it will simply shut down. This works in fatal error and EOF
		1513	callbacks, as well as code outside. It does I<NOT> work in a read or write
		1514	callback, so when you want to destroy the AnyEvent::Handle object from
		1515	within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
		1516	that case.
		1517
		1518	The handle might still linger in the background and write out remaining
		1519	data, as specified by the C<linger> option, however.
		1520
		1521	=cut
		1522
		1523	sub destroy {
		1524	my ($self) = @_;
		1525
		1526	$self->DESTROY;
		1527	%$self = ();
		1528	}
		1529
1411	=item AnyEvent::Handle::TLS_CTX	1530	=item AnyEvent::Handle::TLS_CTX
1412		1531
1413	This function creates and returns the Net::SSLeay::CTX object used by	1532	This function creates and returns the Net::SSLeay::CTX object used by
1414	default for TLS mode.	1533	default for TLS mode.
1415		1534
…		…
1443	}	1562	}
1444	}	1563	}
1445		1564
1446	=back	1565	=back
1447		1566
		1567
		1568	=head1 NONFREQUENTLY ASKED QUESTIONS
		1569
		1570	=over 4
		1571
		1572	=item I C<undef> the AnyEvent::Handle reference inside my callback and
		1573	still get further invocations!
		1574
		1575	That's because AnyEvent::Handle keeps a reference to itself when handling
		1576	read or write callbacks.
		1577
		1578	It is only safe to "forget" the reference inside EOF or error callbacks,
		1579	from within all other callbacks, you need to explicitly call the C<<
		1580	->destroy >> method.
		1581
		1582	=item I get different callback invocations in TLS mode/Why can't I pause
		1583	reading?
		1584
		1585	Unlike, say, TCP, TLS connections do not consist of two independent
		1586	communication channels, one for each direction. Or put differently. The
		1587	read and write directions are not independent of each other: you cannot
		1588	write data unless you are also prepared to read, and vice versa.
		1589
		1590	This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
		1591	callback invocations when you are not expecting any read data - the reason
		1592	is that AnyEvent::Handle always reads in TLS mode.
		1593
		1594	During the connection, you have to make sure that you always have a
		1595	non-empty read-queue, or an C<on_read> watcher. At the end of the
		1596	connection (or when you no longer want to use it) you can call the
		1597	C<destroy> method.
		1598
		1599	=item How do I read data until the other side closes the connection?
		1600
		1601	If you just want to read your data into a perl scalar, the easiest way
		1602	to achieve this is by setting an C<on_read> callback that does nothing,
		1603	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1604	will be in C<$_[0]{rbuf}>:
		1605
		1606	$handle->on_read (sub { });
		1607	$handle->on_eof (undef);
		1608	$handle->on_error (sub {
		1609	my $data = delete $_[0]{rbuf};
		1610	undef $handle;
		1611	});
		1612
		1613	The reason to use C<on_error> is that TCP connections, due to latencies
		1614	and packets loss, might get closed quite violently with an error, when in
		1615	fact, all data has been received.
		1616
		1617	It is usually better to use acknowledgements when transferring data,
		1618	to make sure the other side hasn't just died and you got the data
		1619	intact. This is also one reason why so many internet protocols have an
		1620	explicit QUIT command.
		1621
		1622	=item I don't want to destroy the handle too early - how do I wait until
		1623	all data has been written?
		1624
		1625	After writing your last bits of data, set the C<on_drain> callback
		1626	and destroy the handle in there - with the default setting of
		1627	C<low_water_mark> this will be called precisely when all data has been
		1628	written to the socket:
		1629
		1630	$handle->push_write (...);
		1631	$handle->on_drain (sub {
		1632	warn "all data submitted to the kernel\n";
		1633	undef $handle;
		1634	});
		1635
		1636	=back
		1637
		1638
1448	=head1 SUBCLASSING AnyEvent::Handle	1639	=head1 SUBCLASSING AnyEvent::Handle
1449		1640
1450	In many cases, you might want to subclass AnyEvent::Handle.	1641	In many cases, you might want to subclass AnyEvent::Handle.
1451		1642
1452	To make this easier, a given version of AnyEvent::Handle uses these	1643	To make this easier, a given version of AnyEvent::Handle uses these

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.79 by root, Sun Jul 27 08:37:56 2008 UTC vs. Revision 1.117 by root, Tue Feb 10 14:22:59 2009 UTC

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.79 by root, Sun Jul 27 08:37:56 2008 UTC vs.
Revision 1.117 by root, Tue Feb 10 14:22:59 2009 UTC