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

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.78 by root, Sun Jul 27 07:34:07 2008 UTC vs.
Revision 1.97 by root, Thu Oct 2 11:07:59 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(WSAEWOULDBLOCK);	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
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 $VERSION = 4.3;
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
…		…
49		49
50	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
51	filehandles. For utility functions for doing non-blocking connects and accepts	51	filehandles. For utility functions for doing non-blocking connects and accepts
52	on sockets see L<AnyEvent::Util>.	52	on sockets see L<AnyEvent::Util>.
53		53
		54	The L<AnyEvent::Intro> tutorial contains some well-documented
		55	AnyEvent::Handle examples.
		56
54	In the following, when the documentation refers to of "bytes" then this	57	In the following, when the documentation refers to of "bytes" then this
55	means characters. As sysread and syswrite are used for all I/O, their	58	means characters. As sysread and syswrite are used for all I/O, their
56	treatment of characters applies to this module as well.	59	treatment of characters applies to this module as well.
57		60
58	All callbacks will be invoked with the handle object as their first	61	All callbacks will be invoked with the handle object as their first
59	argument.	62	argument.
60		63
		64	=head2 SIGPIPE is not handled by this module
		65
		66	SIGPIPE is not handled by this module, so one of the practical
		67	requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} =
		68	'IGNORE'>). At least, this is highly recommend in a networked program: If
		69	you use AnyEvent::Handle in a filter program (like sort), exiting on
		70	SIGPIPE is probably the right thing to do.
		71
61	=head1 METHODS	72	=head1 METHODS
62		73
63	=over 4	74	=over 4
64		75
65	=item B<new (%args)>	76	=item B<new (%args)>
…		…
70		81
71	=item fh => $filehandle [MANDATORY]	82	=item fh => $filehandle [MANDATORY]
72		83
73	The filehandle this L<AnyEvent::Handle> object will operate on.	84	The filehandle this L<AnyEvent::Handle> object will operate on.
74		85
75	NOTE: The filehandle will be set to non-blocking (using	86	NOTE: The filehandle will be set to non-blocking mode (using
76	AnyEvent::Util::fh_nonblocking).	87	C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
		88	that mode.
77		89
78	=item on_eof => $cb->($handle)	90	=item on_eof => $cb->($handle)
79		91
80	Set the callback to be called when an end-of-file condition is detected,	92	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	93	i.e. in the case of a socket, when the other side has closed the
82	connection cleanly.	94	connection cleanly.
83		95
		96	For sockets, this just means that the other side has stopped sending data,
		97	you can still try to write data, and, in fact, one can return from the eof
		98	callback and continue writing data, as only the read part has been shut
		99	down.
		100
84	While not mandatory, it is highly recommended to set an eof callback,	101	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	102	otherwise you might end up with a closed socket while you are still
86	waiting for data.	103	waiting for data.
		104
		105	If an EOF condition has been detected but no C<on_eof> callback has been
		106	set, then a fatal error will be raised with C<$!> set to <0>.
87		107
88	=item on_error => $cb->($handle, $fatal)	108	=item on_error => $cb->($handle, $fatal)
89		109
90	This is the error callback, which is called when, well, some error	110	This is the error callback, which is called when, well, some error
91	occured, such as not being able to resolve the hostname, failure to	111	occured, such as not being able to resolve the hostname, failure to
92	connect or a read error.	112	connect or a read error.
93		113
94	Some errors are fatal (which is indicated by C<$fatal> being true). On	114	Some errors are fatal (which is indicated by C<$fatal> being true). On
95	fatal errors the handle object will be shut down and will not be	115	fatal errors the handle object will be shut down and will not be usable
		116	(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
		117	errors are an EOF condition with active (but unsatisifable) read watchers
		118	(C<EPIPE>) or I/O errors.
		119
96	usable. Non-fatal errors can be retried by simply returning, but it is	120	Non-fatal errors can be retried by simply returning, but it is recommended
97	recommended to simply ignore this parameter and instead abondon the handle	121	to simply ignore this parameter and instead abondon the handle object
98	object when this callback is invoked.	122	when this callback is invoked. Examples of non-fatal errors are timeouts
		123	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99		124
100	On callback entrance, the value of C<$!> contains the operating system	125	On callback entrance, the value of C<$!> contains the operating system
101	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).	126	error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
102		127
103	While not mandatory, it is I<highly> recommended to set this callback, as	128	While not mandatory, it is I<highly> recommended to set this callback, as
…		…
135	=item timeout => $fractional_seconds	160	=item timeout => $fractional_seconds
136		161
137	If non-zero, then this enables an "inactivity" timeout: whenever this many	162	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	163	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	164	handle, the C<on_timeout> callback will be invoked (and if that one is
140	missing, an C<ETIMEDOUT> error will be raised).	165	missing, a non-fatal C<ETIMEDOUT> error will be raised).
141		166
142	Note that timeout processing is also active when you currently do not have	167	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	168	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	169	idle then you should disable the timout temporarily or ignore the timeout
145	in the C<on_timeout> callback.	170	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
		171	restart the timeout.
146		172
147	Zero (the default) disables this timeout.	173	Zero (the default) disables this timeout.
148		174
149	=item on_timeout => $cb->($handle)	175	=item on_timeout => $cb->($handle)
150		176
…		…
154		180
155	=item rbuf_max => <bytes>	181	=item rbuf_max => <bytes>
156		182
157	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)	183	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
158	when the read buffer ever (strictly) exceeds this size. This is useful to	184	when the read buffer ever (strictly) exceeds this size. This is useful to
159	avoid denial-of-service attacks.	185	avoid some forms of denial-of-service attacks.
160		186
161	For example, a server accepting connections from untrusted sources should	187	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	188	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	189	(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	190	amount of data without a callback ever being called as long as the line
165	isn't finished).	191	isn't finished).
166		192
167	=item autocork => <boolean>	193	=item autocork => <boolean>
168		194
169	When disabled (the default), then C<push_write> will try to immediately	195	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	196	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	197	a write watcher and wait for the next event loop iteration, but can
172	inefficient if you write multiple small chunks (this disadvantage is	198	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>).	199	disadvantage is usually avoided by your kernel's nagle algorithm, see
		200	C<no_delay>, but this option can save costly syscalls).
174		201
175	When enabled, then writes will always be queued till the next event loop	202	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,	203	iteration. This is efficient when you do many small writes per iteration,
177	but less efficient when you do a single write only.	204	but less efficient when you do a single write only per iteration (or when
		205	the write buffer often is full). It also increases write latency.
178		206
179	=item no_delay => <boolean>	207	=item no_delay => <boolean>
180		208
181	When doing small writes on sockets, your operating system kernel might	209	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	210	wait a bit for more data before actually sending it out. This is called
183	the Nagle algorithm, and usually it is beneficial.	211	the Nagle algorithm, and usually it is beneficial.
184		212
185	In some situations you want as low a delay as possible, which cna be	213	In some situations you want as low a delay as possible, which can be
186	accomplishd by setting this option to true.	214	accomplishd by setting this option to a true value.
187		215
188	The default is your opertaing system's default behaviour, this option	216	The default is your opertaing system's default behaviour (most likely
189	explicitly enables or disables it, if possible.	217	enabled), this option explicitly enables or disables it, if possible.
190		218
191	=item read_size => <bytes>	219	=item read_size => <bytes>
192		220
193	The default read block size (the amount of bytes this module will try to read	221	The default read block size (the amount of bytes this module will
194	during each (loop iteration). Default: C<8192>.	222	try to read during each loop iteration, which affects memory
		223	requirements). Default: C<8192>.
195		224
196	=item low_water_mark => <bytes>	225	=item low_water_mark => <bytes>
197		226
198	Sets the amount of bytes (default: C<0>) that make up an "empty" write	227	Sets the amount of bytes (default: C<0>) that make up an "empty" write
199	buffer: If the write reaches this size or gets even samller it is	228	buffer: If the write reaches this size or gets even samller it is
200	considered empty.	229	considered empty.
201		230
		231	Sometimes it can be beneficial (for performance reasons) to add data to
		232	the write buffer before it is fully drained, but this is a rare case, as
		233	the operating system kernel usually buffers data as well, so the default
		234	is good in almost all cases.
		235
202	=item linger => <seconds>	236	=item linger => <seconds>
203		237
204	If non-zero (default: C<3600>), then the destructor of the	238	If non-zero (default: C<3600>), then the destructor of the
205	AnyEvent::Handle object will check wether there is still outstanding write	239	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	240	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	241	socket. No errors will be reported (this mostly matches how the operating
208	outstanding data at socket close time).	242	system treats outstanding data at socket close time).
209		243
210	This will not work for partial TLS data that could not yet been	244	This will not work for partial TLS data that could not be encoded
211	encoded. This data will be lost.	245	yet. This data will be lost. Calling the C<stoptls> method in time might
		246	help.
212		247
213	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object	248	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object
214		249
215	When this parameter is given, it enables TLS (SSL) mode, that means it	250	When this parameter is given, it enables TLS (SSL) mode, that means
216	will start making tls handshake and will transparently encrypt/decrypt	251	AnyEvent will start a TLS handshake as soon as the conenction has been
217	data.	252	established and will transparently encrypt/decrypt data afterwards.
218		253
219	TLS mode requires Net::SSLeay to be installed (it will be loaded	254	TLS mode requires Net::SSLeay to be installed (it will be loaded
220	automatically when you try to create a TLS handle).	255	automatically when you try to create a TLS handle): this module doesn't
		256	have a dependency on that module, so if your module requires it, you have
		257	to add the dependency yourself.
221		258
222	For the TLS server side, use C<accept>, and for the TLS client side of a	259	Unlike TCP, TLS has a server and client side: for the TLS server side, use
223	connection, use C<connect> mode.	260	C<accept>, and for the TLS client side of a connection, use C<connect>
		261	mode.
224		262
225	You can also provide your own TLS connection object, but you have	263	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>	264	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	265	or C<Net::SSLeay::set_accept_state> on it before you pass it to
228	AnyEvent::Handle.	266	AnyEvent::Handle.
229		267
230	See the C<starttls> method if you need to start TLS negotiation later.	268	See the C<< ->starttls >> method for when need to start TLS negotiation later.
231		269
232	=item tls_ctx => $ssl_ctx	270	=item tls_ctx => $ssl_ctx
233		271
234	Use the given Net::SSLeay::CTX object to create the new TLS connection	272	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	273	(unless a connection object was specified directly). If this parameter is
236	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.	274	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
237		275
238	=item json => JSON or JSON::XS object	276	=item json => JSON or JSON::XS object
239		277
240	This is the json coder object used by the C<json> read and write types.	278	This is the json coder object used by the C<json> read and write types.
241		279
242	If you don't supply it, then AnyEvent::Handle will create and use a	280	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.	281	suitable one (on demand), which will write and expect UTF-8 encoded JSON
		282	texts.
244		283
245	Note that you are responsible to depend on the JSON module if you want to	284	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.	285	use this functionality, as AnyEvent does not have a dependency itself.
247		286
248	=item filter_r => $cb
249
250	=item filter_w => $cb
251
252	These exist, but are undocumented at this time.
253
254	=back	287	=back
255		288
256	=cut	289	=cut
257		290
258	sub new {	291	sub new {
…		…
262		295
263	$self->{fh} or Carp::croak "mandatory argument fh is missing";	296	$self->{fh} or Carp::croak "mandatory argument fh is missing";
264		297
265	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	298	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
266		299
267	if ($self->{tls}) {
268	require Net::SSLeay;
269	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});	300	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
270	}	301	if $self->{tls};
271		302
272	$self->{_activity} = AnyEvent->now;	303	$self->{_activity} = AnyEvent->now;
273	$self->_timeout;	304	$self->_timeout;
274		305
275	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};	306	$self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
…		…
287	delete $self->{_tw};	318	delete $self->{_tw};
288	delete $self->{_rw};	319	delete $self->{_rw};
289	delete $self->{_ww};	320	delete $self->{_ww};
290	delete $self->{fh};	321	delete $self->{fh};
291		322
292	$self->stoptls;	323	&_freetls;
		324
		325	delete $self->{on_read};
		326	delete $self->{_queue};
293	}	327	}
294		328
295	sub _error {	329	sub _error {
296	my ($self, $errno, $fatal) = @_;	330	my ($self, $errno, $fatal) = @_;
297		331
…		…
307	}	341	}
308	}	342	}
309		343
310	=item $fh = $handle->fh	344	=item $fh = $handle->fh
311		345
312	This method returns the file handle of the L<AnyEvent::Handle> object.	346	This method returns the file handle used to create the L<AnyEvent::Handle> object.
313		347
314	=cut	348	=cut
315		349
316	sub fh { $_[0]{fh} }	350	sub fh { $_[0]{fh} }
317		351
…		…
335	$_[0]{on_eof} = $_[1];	369	$_[0]{on_eof} = $_[1];
336	}	370	}
337		371
338	=item $handle->on_timeout ($cb)	372	=item $handle->on_timeout ($cb)
339		373
340	Replace the current C<on_timeout> callback, or disables the callback	374	Replace the current C<on_timeout> callback, or disables the callback (but
341	(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor	375	not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
342	argument.	376	argument and method.
343		377
344	=cut	378	=cut
345		379
346	sub on_timeout {	380	sub on_timeout {
347	$_[0]{on_timeout} = $_[1];	381	$_[0]{on_timeout} = $_[1];
…		…
453	my ($self, $cb) = @_;	487	my ($self, $cb) = @_;
454		488
455	$self->{on_drain} = $cb;	489	$self->{on_drain} = $cb;
456		490
457	$cb->($self)	491	$cb->($self)
458	if $cb && $self->{low_water_mark} >= length $self->{wbuf};	492	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
459	}	493	}
460		494
461	=item $handle->push_write ($data)	495	=item $handle->push_write ($data)
462		496
463	Queues the given scalar to be written. You can push as much data as you	497	Queues the given scalar to be written. You can push as much data as you
…		…
480	substr $self->{wbuf}, 0, $len, "";	514	substr $self->{wbuf}, 0, $len, "";
481		515
482	$self->{_activity} = AnyEvent->now;	516	$self->{_activity} = AnyEvent->now;
483		517
484	$self->{on_drain}($self)	518	$self->{on_drain}($self)
485	if $self->{low_water_mark} >= length $self->{wbuf}	519	if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
486	&& $self->{on_drain};	520	&& $self->{on_drain};
487		521
488	delete $self->{_ww} unless length $self->{wbuf};	522	delete $self->{_ww} unless length $self->{wbuf};
489	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {	523	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
490	$self->_error ($!, 1);	524	$self->_error ($!, 1);
…		…
514		548
515	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")	549	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
516	->($self, @_);	550	->($self, @_);
517	}	551	}
518		552
519	if ($self->{filter_w}) {	553	if ($self->{tls}) {
520	$self->{filter_w}($self, \$_[0]);	554	$self->{_tls_wbuf} .= $_[0];
		555
		556	&_dotls ($self);
521	} else {	557	} else {
522	$self->{wbuf} .= $_[0];	558	$self->{wbuf} .= $_[0];
523	$self->_drain_wbuf;	559	$self->_drain_wbuf;
524	}	560	}
525	}	561	}
…		…
542	=cut	578	=cut
543		579
544	register_write_type netstring => sub {	580	register_write_type netstring => sub {
545	my ($self, $string) = @_;	581	my ($self, $string) = @_;
546		582
547	sprintf "%d:%s,", (length $string), $string	583	(length $string) . ":$string,"
548	};	584	};
549		585
550	=item packstring => $format, $data	586	=item packstring => $format, $data
551		587
552	An octet string prefixed with an encoded length. The encoding C<$format>	588	An octet string prefixed with an encoded length. The encoding C<$format>
…		…
726		762
727	if (	763	if (
728	defined $self->{rbuf_max}	764	defined $self->{rbuf_max}
729	&& $self->{rbuf_max} < length $self->{rbuf}	765	&& $self->{rbuf_max} < length $self->{rbuf}
730	) {	766	) {
731	return $self->_error (&Errno::ENOSPC, 1);	767	$self->_error (&Errno::ENOSPC, 1), return;
732	}	768	}
733		769
734	while () {	770	while () {
735	no strict 'refs';
736
737	my $len = length $self->{rbuf};	771	my $len = length $self->{rbuf};
738		772
739	if (my $cb = shift @{ $self->{_queue} }) {	773	if (my $cb = shift @{ $self->{_queue} }) {
740	unless ($cb->($self)) {	774	unless ($cb->($self)) {
741	if ($self->{_eof}) {	775	if ($self->{_eof}) {
742	# no progress can be made (not enough data and no data forthcoming)	776	# no progress can be made (not enough data and no data forthcoming)
743	$self->_error (&Errno::EPIPE, 1), last;	777	$self->_error (&Errno::EPIPE, 1), return;
744	}	778	}
745		779
746	unshift @{ $self->{_queue} }, $cb;	780	unshift @{ $self->{_queue} }, $cb;
747	last;	781	last;
748	}	782	}
…		…
756	&& !@{ $self->{_queue} } # and the queue is still empty	790	&& !@{ $self->{_queue} } # and the queue is still empty
757	&& $self->{on_read} # but we still have on_read	791	&& $self->{on_read} # but we still have on_read
758	) {	792	) {
759	# no further data will arrive	793	# no further data will arrive
760	# so no progress can be made	794	# so no progress can be made
761	$self->_error (&Errno::EPIPE, 1), last	795	$self->_error (&Errno::EPIPE, 1), return
762	if $self->{_eof};	796	if $self->{_eof};
763		797
764	last; # more data might arrive	798	last; # more data might arrive
765	}	799	}
766	} else {	800	} else {
767	# read side becomes idle	801	# read side becomes idle
768	delete $self->{_rw};	802	delete $self->{_rw} unless $self->{tls};
769	last;	803	last;
770	}	804	}
771	}	805	}
772		806
		807	if ($self->{_eof}) {
		808	if ($self->{on_eof}) {
773	$self->{on_eof}($self)	809	$self->{on_eof}($self)
774	if $self->{_eof} && $self->{on_eof};	810	} else {
		811	$self->_error (0, 1);
		812	}
		813	}
775		814
776	# may need to restart read watcher	815	# may need to restart read watcher
777	unless ($self->{_rw}) {	816	unless ($self->{_rw}) {
778	$self->start_read	817	$self->start_read
779	if $self->{on_read} \|\| @{ $self->{_queue} };	818	if $self->{on_read} \|\| @{ $self->{_queue} };
…		…
1063	An octet string prefixed with an encoded length. The encoding C<$format>	1102	An octet string prefixed with an encoded length. The encoding C<$format>
1064	uses the same format as a Perl C<pack> format, but must specify a single	1103	uses the same format as a Perl C<pack> format, but must specify a single
1065	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an	1104	integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1066	optional C<!>, C<< < >> or C<< > >> modifier).	1105	optional C<!>, C<< < >> or C<< > >> modifier).
1067		1106
1068	DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.	1107	For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
		1108	EPP uses a prefix of C<N> (4 octtes).
1069		1109
1070	Example: read a block of data prefixed by its length in BER-encoded	1110	Example: read a block of data prefixed by its length in BER-encoded
1071	format (very efficient).	1111	format (very efficient).
1072		1112
1073	$handle->push_read (packstring => "w", sub {	1113	$handle->push_read (packstring => "w", sub {
…		…
1226	Note that AnyEvent::Handle will automatically C<start_read> for you when	1266	Note that AnyEvent::Handle will automatically C<start_read> for you when
1227	you change the C<on_read> callback or push/unshift a read callback, and it	1267	you change the C<on_read> callback or push/unshift a read callback, and it
1228	will automatically C<stop_read> for you when neither C<on_read> is set nor	1268	will automatically C<stop_read> for you when neither C<on_read> is set nor
1229	there are any read requests in the queue.	1269	there are any read requests in the queue.
1230		1270
		1271	These methods will have no effect when in TLS mode (as TLS doesn't support
		1272	half-duplex connections).
		1273
1231	=cut	1274	=cut
1232		1275
1233	sub stop_read {	1276	sub stop_read {
1234	my ($self) = @_;	1277	my ($self) = @_;
1235		1278
1236	delete $self->{_rw};	1279	delete $self->{_rw} unless $self->{tls};
1237	}	1280	}
1238		1281
1239	sub start_read {	1282	sub start_read {
1240	my ($self) = @_;	1283	my ($self) = @_;
1241		1284
1242	unless ($self->{_rw} \|\| $self->{_eof}) {	1285	unless ($self->{_rw} \|\| $self->{_eof}) {
1243	Scalar::Util::weaken $self;	1286	Scalar::Util::weaken $self;
1244		1287
1245	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {	1288	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1246	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};	1289	my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1247	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;	1290	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;
1248		1291
1249	if ($len > 0) {	1292	if ($len > 0) {
1250	$self->{_activity} = AnyEvent->now;	1293	$self->{_activity} = AnyEvent->now;
1251		1294
1252	$self->{filter_r}	1295	if ($self->{tls}) {
1253	? $self->{filter_r}($self, $rbuf)	1296	Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1254	: $self->{_in_drain} \|\| $self->_drain_rbuf;	1297
		1298	&_dotls ($self);
		1299	} else {
		1300	$self->_drain_rbuf unless $self->{_in_drain};
		1301	}
1255		1302
1256	} elsif (defined $len) {	1303	} elsif (defined $len) {
1257	delete $self->{_rw};	1304	delete $self->{_rw};
1258	$self->{_eof} = 1;	1305	$self->{_eof} = 1;
1259	$self->_drain_rbuf unless $self->{_in_drain};	1306	$self->_drain_rbuf unless $self->{_in_drain};
…		…
1263	}	1310	}
1264	});	1311	});
1265	}	1312	}
1266	}	1313	}
1267		1314
		1315	# poll the write BIO and send the data if applicable
1268	sub _dotls {	1316	sub _dotls {
1269	my ($self) = @_;	1317	my ($self) = @_;
1270		1318
1271	my $buf;	1319	my $tmp;
1272		1320
1273	if (length $self->{_tls_wbuf}) {	1321	if (length $self->{_tls_wbuf}) {
1274	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {	1322	while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1275	substr $self->{_tls_wbuf}, 0, $len, "";	1323	substr $self->{_tls_wbuf}, 0, $tmp, "";
1276	}	1324	}
1277	}	1325	}
1278		1326
1279	if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1280	$self->{wbuf} .= $buf;
1281	$self->_drain_wbuf;
1282	}
1283
1284	while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {	1327	while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1285	if (length $buf) {	1328	unless (length $tmp) {
1286	$self->{rbuf} .= $buf;
1287	$self->_drain_rbuf unless $self->{_in_drain};
1288	} else {
1289	# let's treat SSL-eof as we treat normal EOF	1329	# let's treat SSL-eof as we treat normal EOF
		1330	delete $self->{_rw};
1290	$self->{_eof} = 1;	1331	$self->{_eof} = 1;
1291	$self->_shutdown;	1332	&_freetls;
1292	return;
1293	}	1333	}
1294	}
1295		1334
		1335	$self->{rbuf} .= $tmp;
		1336	$self->_drain_rbuf unless $self->{_in_drain};
		1337	$self->{tls} or return; # tls session might have gone away in callback
		1338	}
		1339
1296	my $err = Net::SSLeay::get_error ($self->{tls}, -1);	1340	$tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1297		1341
1298	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {	1342	if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1299	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {	1343	if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1300	return $self->_error ($!, 1);	1344	return $self->_error ($!, 1);
1301	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {	1345	} elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1302	return $self->_error (&Errno::EIO, 1);	1346	return $self->_error (&Errno::EIO, 1);
1303	}	1347	}
1304		1348
1305	# all others are fine for our purposes	1349	# all other errors are fine for our purposes
		1350	}
		1351
		1352	while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		1353	$self->{wbuf} .= $tmp;
		1354	$self->_drain_wbuf;
1306	}	1355	}
1307	}	1356	}
1308		1357
1309	=item $handle->starttls ($tls[, $tls_ctx])	1358	=item $handle->starttls ($tls[, $tls_ctx])
1310		1359
…		…
1320		1369
1321	The TLS connection object will end up in C<< $handle->{tls} >> after this	1370	The TLS connection object will end up in C<< $handle->{tls} >> after this
1322	call and can be used or changed to your liking. Note that the handshake	1371	call and can be used or changed to your liking. Note that the handshake
1323	might have already started when this function returns.	1372	might have already started when this function returns.
1324		1373
		1374	If it an error to start a TLS handshake more than once per
		1375	AnyEvent::Handle object (this is due to bugs in OpenSSL).
		1376
1325	=cut	1377	=cut
1326		1378
1327	sub starttls {	1379	sub starttls {
1328	my ($self, $ssl, $ctx) = @_;	1380	my ($self, $ssl, $ctx) = @_;
1329		1381
1330	$self->stoptls;	1382	require Net::SSLeay;
1331		1383
		1384	Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object"
		1385	if $self->{tls};
		1386
1332	if ($ssl eq "accept") {	1387	if ($ssl eq "accept") {
1333	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1388	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
1334	Net::SSLeay::set_accept_state ($ssl);	1389	Net::SSLeay::set_accept_state ($ssl);
1335	} elsif ($ssl eq "connect") {	1390	} elsif ($ssl eq "connect") {
1336	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());	1391	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
…		…
1342	# basically, this is deep magic (because SSL_read should have the same issues)	1397	# basically, this is deep magic (because SSL_read should have the same issues)
1343	# but the openssl maintainers basically said: "trust us, it just works".	1398	# but the openssl maintainers basically said: "trust us, it just works".
1344	# (unfortunately, we have to hardcode constants because the abysmally misdesigned	1399	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
1345	# and mismaintained ssleay-module doesn't even offer them).	1400	# and mismaintained ssleay-module doesn't even offer them).
1346	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html	1401	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1402	#
		1403	# in short: this is a mess.
		1404	#
		1405	# note that we do not try to keep the length constant between writes as we are required to do.
		1406	# we assume that most (but not all) of this insanity only applies to non-blocking cases,
		1407	# and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
		1408	# have identity issues in that area.
1347	Net::SSLeay::CTX_set_mode ($self->{tls},	1409	Net::SSLeay::CTX_set_mode ($self->{tls},
1348	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)	1410	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)
1349	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));	1411	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));
1350		1412
1351	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1413	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1352	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	1414	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1353		1415
1354	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});	1416	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1355		1417
1356	$self->{filter_w} = sub {	1418	&_dotls; # need to trigger the initial handshake
1357	$_[0]{_tls_wbuf} .= ${$_[1]};	1419	$self->start_read; # make sure we actually do read
1358	&_dotls;
1359	};
1360	$self->{filter_r} = sub {
1361	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1362	&_dotls;
1363	};
1364	}	1420	}
1365		1421
1366	=item $handle->stoptls	1422	=item $handle->stoptls
1367		1423
1368	Destroys the SSL connection, if any. Partial read or write data will be	1424	Shuts down the SSL connection - this makes a proper EOF handshake by
1369	lost.	1425	sending a close notify to the other side, but since OpenSSL doesn't
		1426	support non-blocking shut downs, it is not possible to re-use the stream
		1427	afterwards.
1370		1428
1371	=cut	1429	=cut
1372		1430
1373	sub stoptls {	1431	sub stoptls {
1374	my ($self) = @_;	1432	my ($self) = @_;
1375		1433
		1434	if ($self->{tls}) {
		1435	Net::SSLeay::shutdown ($self->{tls});
		1436
		1437	&_dotls;
		1438
		1439	# we don't give a shit. no, we do, but we can't. no...
		1440	# we, we... have to use openssl :/
		1441	&_freetls;
		1442	}
		1443	}
		1444
		1445	sub _freetls {
		1446	my ($self) = @_;
		1447
		1448	return unless $self->{tls};
		1449
1376	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};	1450	Net::SSLeay::free (delete $self->{tls});
1377		1451
1378	delete $self->{_rbio};	1452	delete @$self{qw(_rbio _wbio _tls_wbuf)};
1379	delete $self->{_wbio};
1380	delete $self->{_tls_wbuf};
1381	delete $self->{filter_r};
1382	delete $self->{filter_w};
1383	}	1453	}
1384		1454
1385	sub DESTROY {	1455	sub DESTROY {
1386	my $self = shift;	1456	my $self = shift;
1387		1457
1388	$self->stoptls;	1458	&_freetls;
1389		1459
1390	my $linger = exists $self->{linger} ? $self->{linger} : 3600;	1460	my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1391		1461
1392	if ($linger && length $self->{wbuf}) {	1462	if ($linger && length $self->{wbuf}) {
1393	my $fh = delete $self->{fh};	1463	my $fh = delete $self->{fh};
…		…
1445	}	1515	}
1446	}	1516	}
1447		1517
1448	=back	1518	=back
1449		1519
		1520
		1521	=head1 NONFREQUENTLY ASKED QUESTIONS
		1522
		1523	=over 4
		1524
		1525	=item How do I read data until the other side closes the connection?
		1526
		1527	If you just want to read your data into a perl scalar, the easiest way
		1528	to achieve this is by setting an C<on_read> callback that does nothing,
		1529	clearing the C<on_eof> callback and in the C<on_error> callback, the data
		1530	will be in C<$_[0]{rbuf}>:
		1531
		1532	$handle->on_read (sub { });
		1533	$handle->on_eof (undef);
		1534	$handle->on_error (sub {
		1535	my $data = delete $_[0]{rbuf};
		1536	undef $handle;
		1537	});
		1538
		1539	The reason to use C<on_error> is that TCP connections, due to latencies
		1540	and packets loss, might get closed quite violently with an error, when in
		1541	fact, all data has been received.
		1542
		1543	It is usually better to use acknowledgements when transfering data,
		1544	to make sure the other side hasn't just died and you got the data
		1545	intact. This is also one reason why so many internet protocols have an
		1546	explicit QUIT command.
		1547
		1548
		1549	=item I don't want to destroy the handle too early - how do I wait until
		1550	all data has been written?
		1551
		1552	After writing your last bits of data, set the C<on_drain> callback
		1553	and destroy the handle in there - with the default setting of
		1554	C<low_water_mark> this will be called precisely when all data has been
		1555	written to the socket:
		1556
		1557	$handle->push_write (...);
		1558	$handle->on_drain (sub {
		1559	warn "all data submitted to the kernel\n";
		1560	undef $handle;
		1561	});
		1562
		1563	=back
		1564
		1565
1450	=head1 SUBCLASSING AnyEvent::Handle	1566	=head1 SUBCLASSING AnyEvent::Handle
1451		1567
1452	In many cases, you might want to subclass AnyEvent::Handle.	1568	In many cases, you might want to subclass AnyEvent::Handle.
1453		1569
1454	To make this easier, a given version of AnyEvent::Handle uses these	1570	To make this easier, a given version of AnyEvent::Handle uses these

Diff Legend

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

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.78 by root, Sun Jul 27 07:34:07 2008 UTC vs. Revision 1.97 by root, Thu Oct 2 11:07:59 2008 UTC

Diff Legend

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.78 by root, Sun Jul 27 07:34:07 2008 UTC vs.
Revision 1.97 by root, Thu Oct 2 11:07:59 2008 UTC