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

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.207 by root, Mon Nov 15 22:29:36 2010 UTC vs.
Revision 1.233 by root, Thu Apr 5 06:14:10 2012 UTC

…		…
11		11
12	my $hdl; $hdl = new AnyEvent::Handle	12	my $hdl; $hdl = new AnyEvent::Handle
13	fh => \*STDIN,	13	fh => \*STDIN,
14	on_error => sub {	14	on_error => sub {
15	my ($hdl, $fatal, $msg) = @_;	15	my ($hdl, $fatal, $msg) = @_;
16	warn "got error $msg\n";	16	AE::log error => $msg;
17	$hdl->destroy;	17	$hdl->destroy;
18	$cv->send;	18	$cv->send;
19	};	19	};
20		20
21	# send some request line	21	# send some request line
22	$hdl->push_write ("getinfo\015\012");	22	$hdl->push_write ("getinfo\015\012");
23		23
24	# read the response line	24	# read the response line
25	$hdl->push_read (line => sub {	25	$hdl->push_read (line => sub {
26	my ($hdl, $line) = @_;	26	my ($hdl, $line) = @_;
27	warn "got line <$line>\n";	27	say "got line <$line>";
28	$cv->send;	28	$cv->send;
29	});	29	});
30		30
31	$cv->recv;	31	$cv->recv;
32		32
…		…
114	=over 4	114	=over 4
115		115
116	=item on_prepare => $cb->($handle)	116	=item on_prepare => $cb->($handle)
117		117
118	This (rarely used) callback is called before a new connection is	118	This (rarely used) callback is called before a new connection is
119	attempted, but after the file handle has been created. It could be used to	119	attempted, but after the file handle has been created (you can access that
		120	file handle via C<< $handle->{fh} >>). It could be used to prepare the
120	prepare the file handle with parameters required for the actual connect	121	file handle with parameters required for the actual connect (as opposed to
121	(as opposed to settings that can be changed when the connection is already	122	settings that can be changed when the connection is already established).
122	established).
123		123
124	The return value of this callback should be the connect timeout value in	124	The return value of this callback should be the connect timeout value in
125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the	125	seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126	default timeout is to be used).	126	default timeout is to be used).
127		127
128	=item on_connect => $cb->($handle, $host, $port, $retry->())	128	=item on_connect => $cb->($handle, $host, $port, $retry->())
129		129
130	This callback is called when a connection has been successfully established.	130	This callback is called when a connection has been successfully established.
131		131
132	The peer's numeric host and port (the socket peername) are passed as	132	The peer's numeric host and port (the socket peername) are passed as
133	parameters, together with a retry callback.	133	parameters, together with a retry callback. At the time it is called the
		134	read and write queues, EOF status, TLS status and similar properties of
		135	the handle will have been reset.
134		136
		137	It is not allowed to use the read or write queues while the handle object
		138	is connecting.
		139
135	If, for some reason, the handle is not acceptable, calling C<$retry>	140	If, for some reason, the handle is not acceptable, calling C<$retry> will
136	will continue with the next connection target (in case of multi-homed	141	continue with the next connection target (in case of multi-homed hosts or
137	hosts or SRV records there can be multiple connection endpoints). At the	142	SRV records there can be multiple connection endpoints). The C<$retry>
138	time it is called the read and write queues, eof status, tls status and	143	callback can be invoked after the connect callback returns, i.e. one can
139	similar properties of the handle will have been reset.	144	start a handshake and then decide to retry with the next host if the
		145	handshake fails.
140		146
141	In most cases, you should ignore the C<$retry> parameter.	147	In most cases, you should ignore the C<$retry> parameter.
142		148
143	=item on_connect_error => $cb->($handle, $message)	149	=item on_connect_error => $cb->($handle, $message)
144		150
…		…
164	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In	170	with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
165	cases where the other side can close the connection at will, it is	171	cases where the other side can close the connection at will, it is
166	often easiest to not report C<EPIPE> errors in this callback.	172	often easiest to not report C<EPIPE> errors in this callback.
167		173
168	AnyEvent::Handle tries to find an appropriate error code for you to check	174	AnyEvent::Handle tries to find an appropriate error code for you to check
169	against, but in some cases (TLS errors), this does not work well. It is	175	against, but in some cases (TLS errors), this does not work well.
170	recommended to always output the C<$message> argument in human-readable	176
171	error messages (it's usually the same as C<"$!">).	177	If you report the error to the user, it is recommended to always output
		178	the C<$message> argument in human-readable error messages (you don't need
		179	to report C<"$!"> if you report C<$message>).
		180
		181	If you want to react programmatically to the error, then looking at C<$!>
		182	and comparing it against some of the documented C<Errno> values is usually
		183	better than looking at the C<$message>.
172		184
173	Non-fatal errors can be retried by returning, but it is recommended	185	Non-fatal errors can be retried by returning, but it is recommended
174	to simply ignore this parameter and instead abondon the handle object	186	to simply ignore this parameter and instead abondon the handle object
175	when this callback is invoked. Examples of non-fatal errors are timeouts	187	when this callback is invoked. Examples of non-fatal errors are timeouts
176	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).	188	C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
…		…
224	If an EOF condition has been detected but no C<on_eof> callback has been	236	If an EOF condition has been detected but no C<on_eof> callback has been
225	set, then a fatal error will be raised with C<$!> set to <0>.	237	set, then a fatal error will be raised with C<$!> set to <0>.
226		238
227	=item on_drain => $cb->($handle)	239	=item on_drain => $cb->($handle)
228		240
229	This sets the callback that is called when the write buffer becomes empty	241	This sets the callback that is called once when the write buffer becomes
230	(or immediately if the buffer is empty already).	242	empty (and immediately when the handle object is created).
231		243
232	To append to the write buffer, use the C<< ->push_write >> method.	244	To append to the write buffer, use the C<< ->push_write >> method.
233		245
234	This callback is useful when you don't want to put all of your write data	246	This callback is useful when you don't want to put all of your write data
235	into the queue at once, for example, when you want to write the contents	247	into the queue at once, for example, when you want to write the contents
…		…
247	many seconds pass without a successful read or write on the underlying	259	many seconds pass without a successful read or write on the underlying
248	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback	260	file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
249	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>	261	will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
250	error will be raised).	262	error will be raised).
251		263
252	There are three variants of the timeouts that work independently	264	There are three variants of the timeouts that work independently of each
253	of each other, for both read and write, just read, and just write:	265	other, for both read and write (triggered when nothing was read I<OR>
		266	written), just read (triggered when nothing was read), and just write:
254	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks	267	C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
255	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions	268	C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
256	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.	269	C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
257		270
258	Note that timeout processing is active even when you do not have	271	Note that timeout processing is active even when you do not have any
259	any outstanding read or write requests: If you plan to keep the connection	272	outstanding read or write requests: If you plan to keep the connection
260	idle then you should disable the timeout temporarily or ignore the timeout	273	idle then you should disable the timeout temporarily or ignore the
261	in the C<on_timeout> callback, in which case AnyEvent::Handle will simply	274	timeout in the corresponding C<on_timeout> callback, in which case
262	restart the timeout.	275	AnyEvent::Handle will simply restart the timeout.
263		276
264	Zero (the default) disables this timeout.	277	Zero (the default) disables the corresponding timeout.
265		278
266	=item on_timeout => $cb->($handle)	279	=item on_timeout => $cb->($handle)
		280
		281	=item on_rtimeout => $cb->($handle)
		282
		283	=item on_wtimeout => $cb->($handle)
267		284
268	Called whenever the inactivity timeout passes. If you return from this	285	Called whenever the inactivity timeout passes. If you return from this
269	callback, then the timeout will be reset as if some activity had happened,	286	callback, then the timeout will be reset as if some activity had happened,
270	so this condition is not fatal in any way.	287	so this condition is not fatal in any way.
271		288
…		…
278	For example, a server accepting connections from untrusted sources should	295	For example, a server accepting connections from untrusted sources should
279	be configured to accept only so-and-so much data that it cannot act on	296	be configured to accept only so-and-so much data that it cannot act on
280	(for example, when expecting a line, an attacker could send an unlimited	297	(for example, when expecting a line, an attacker could send an unlimited
281	amount of data without a callback ever being called as long as the line	298	amount of data without a callback ever being called as long as the line
282	isn't finished).	299	isn't finished).
		300
		301	=item wbuf_max => <bytes>
		302
		303	If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
		304	when the write buffer ever (strictly) exceeds this size. This is useful to
		305	avoid some forms of denial-of-service attacks.
		306
		307	Although the units of this parameter is bytes, this is the I<raw> number
		308	of bytes not yet accepted by the kernel. This can make a difference when
		309	you e.g. use TLS, as TLS typically makes your write data larger (but it
		310	can also make it smaller due to compression).
		311
		312	As an example of when this limit is useful, take a chat server that sends
		313	chat messages to a client. If the client does not read those in a timely
		314	manner then the send buffer in the server would grow unbounded.
283		315
284	=item autocork => <boolean>	316	=item autocork => <boolean>
285		317
286	When disabled (the default), C<push_write> will try to immediately	318	When disabled (the default), C<push_write> will try to immediately
287	write the data to the handle if possible. This avoids having to register	319	write the data to the handle if possible. This avoids having to register
…		…
339	already have occured on BSD systems), but at least it will protect you	371	already have occured on BSD systems), but at least it will protect you
340	from most attacks.	372	from most attacks.
341		373
342	=item read_size => <bytes>	374	=item read_size => <bytes>
343		375
344	The initial read block size, the number of bytes this module will try to	376	The initial read block size, the number of bytes this module will try
345	read during each loop iteration. Each handle object will consume at least	377	to read during each loop iteration. Each handle object will consume
346	this amount of memory for the read buffer as well, so when handling many	378	at least this amount of memory for the read buffer as well, so when
347	connections requirements). See also C<max_read_size>. Default: C<2048>.	379	handling many connections watch out for memory requirements). See also
		380	C<max_read_size>. Default: C<2048>.
348		381
349	=item max_read_size => <bytes>	382	=item max_read_size => <bytes>
350		383
351	The maximum read buffer size used by the dynamic adjustment	384	The maximum read buffer size used by the dynamic adjustment
352	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in	385	algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
…		…
521	});	554	});
522		555
523	} else {	556	} else {
524	if ($self->{on_connect_error}) {	557	if ($self->{on_connect_error}) {
525	$self->{on_connect_error}($self, "$!");	558	$self->{on_connect_error}($self, "$!");
526	$self->destroy;	559	$self->destroy if $self;
527	} else {	560	} else {
528	$self->_error ($!, 1);	561	$self->_error ($!, 1);
529	}	562	}
530	}	563	}
531	},	564	},
532	sub {	565	sub {
533	local $self->{fh} = $_[0];	566	local $self->{fh} = $_[0];
534		567
535	$self->{on_prepare}	568	$self->{on_prepare}
536	? $self->{on_prepare}->($self)	569	? $self->{on_prepare}->($self)
537	: ()	570	: ()
538	}	571	}
539	);	572	);
540	}	573	}
541		574
…		…
740		773
741	=item $handle->rbuf_max ($max_octets)	774	=item $handle->rbuf_max ($max_octets)
742		775
743	Configures the C<rbuf_max> setting (C<undef> disables it).	776	Configures the C<rbuf_max> setting (C<undef> disables it).
744		777
		778	=item $handle->wbuf_max ($max_octets)
		779
		780	Configures the C<wbuf_max> setting (C<undef> disables it).
		781
745	=cut	782	=cut
746		783
747	sub rbuf_max {	784	sub rbuf_max {
748	$_[0]{rbuf_max} = $_[1];	785	$_[0]{rbuf_max} = $_[1];
749	}	786	}
750		787
		788	sub wbuf_max {
		789	$_[0]{wbuf_max} = $_[1];
		790	}
		791
751	#############################################################################	792	#############################################################################
752		793
753	=item $handle->timeout ($seconds)	794	=item $handle->timeout ($seconds)
754		795
755	=item $handle->rtimeout ($seconds)	796	=item $handle->rtimeout ($seconds)
756		797
757	=item $handle->wtimeout ($seconds)	798	=item $handle->wtimeout ($seconds)
758		799
759	Configures (or disables) the inactivity timeout.	800	Configures (or disables) the inactivity timeout.
		801
		802	The timeout will be checked instantly, so this method might destroy the
		803	handle before it returns.
760		804
761	=item $handle->timeout_reset	805	=item $handle->timeout_reset
762		806
763	=item $handle->rtimeout_reset	807	=item $handle->rtimeout_reset
764		808
…		…
848		892
849	The write queue is very simple: you can add data to its end, and	893	The write queue is very simple: you can add data to its end, and
850	AnyEvent::Handle will automatically try to get rid of it for you.	894	AnyEvent::Handle will automatically try to get rid of it for you.
851		895
852	When data could be written and the write buffer is shorter then the low	896	When data could be written and the write buffer is shorter then the low
853	water mark, the C<on_drain> callback will be invoked.	897	water mark, the C<on_drain> callback will be invoked once.
854		898
855	=over 4	899	=over 4
856		900
857	=item $handle->on_drain ($cb)	901	=item $handle->on_drain ($cb)
858		902
…		…
873	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});	917	if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
874	}	918	}
875		919
876	=item $handle->push_write ($data)	920	=item $handle->push_write ($data)
877		921
878	Queues the given scalar to be written. You can push as much data as you	922	Queues the given scalar to be written. You can push as much data as
879	want (only limited by the available memory), as C<AnyEvent::Handle>	923	you want (only limited by the available memory and C<wbuf_max>), as
880	buffers it independently of the kernel.	924	C<AnyEvent::Handle> buffers it independently of the kernel.
881		925
882	This method may invoke callbacks (and therefore the handle might be	926	This method may invoke callbacks (and therefore the handle might be
883	destroyed after it returns).	927	destroyed after it returns).
884		928
885	=cut	929	=cut
…		…
913	$cb->() unless $self->{autocork};	957	$cb->() unless $self->{autocork};
914		958
915	# if still data left in wbuf, we need to poll	959	# if still data left in wbuf, we need to poll
916	$self->{_ww} = AE::io $self->{fh}, 1, $cb	960	$self->{_ww} = AE::io $self->{fh}, 1, $cb
917	if length $self->{wbuf};	961	if length $self->{wbuf};
		962
		963	if (
		964	defined $self->{wbuf_max}
		965	&& $self->{wbuf_max} < length $self->{wbuf}
		966	) {
		967	$self->_error (Errno::ENOSPC, 1), return;
		968	}
918	};	969	};
919	}	970	}
920		971
921	our %WH;	972	our %WH;
922		973
…		…
1042	=cut	1093	=cut
1043		1094
1044	register_write_type storable => sub {	1095	register_write_type storable => sub {
1045	my ($self, $ref) = @_;	1096	my ($self, $ref) = @_;
1046		1097
1047	require Storable;	1098	require Storable unless $Storable::VERSION;
1048		1099
1049	pack "w/a*", Storable::nfreeze ($ref)	1100	pack "w/a*", Storable::nfreeze ($ref)
1050	};	1101	};
1051		1102
1052	=back	1103	=back
…		…
1057	before it was actually written. One way to do that is to replace your	1108	before it was actually written. One way to do that is to replace your
1058	C<on_drain> handler by a callback that shuts down the socket (and set	1109	C<on_drain> handler by a callback that shuts down the socket (and set
1059	C<low_water_mark> to C<0>). This method is a shorthand for just that, and	1110	C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1060	replaces the C<on_drain> callback with:	1111	replaces the C<on_drain> callback with:
1061		1112
1062	sub { shutdown $_[0]{fh}, 1 } # for push_shutdown	1113	sub { shutdown $_[0]{fh}, 1 }
1063		1114
1064	This simply shuts down the write side and signals an EOF condition to the	1115	This simply shuts down the write side and signals an EOF condition to the
1065	the peer.	1116	the peer.
1066		1117
1067	You can rely on the normal read queue and C<on_eof> handling	1118	You can rely on the normal read queue and C<on_eof> handling
…		…
1089		1140
1090	Whenever the given C<type> is used, C<push_write> will the function with	1141	Whenever the given C<type> is used, C<push_write> will the function with
1091	the handle object and the remaining arguments.	1142	the handle object and the remaining arguments.
1092		1143
1093	The function is supposed to return a single octet string that will be	1144	The function is supposed to return a single octet string that will be
1094	appended to the write buffer, so you cna mentally treat this function as a	1145	appended to the write buffer, so you can mentally treat this function as a
1095	"arguments to on-the-wire-format" converter.	1146	"arguments to on-the-wire-format" converter.
1096		1147
1097	Example: implement a custom write type C<join> that joins the remaining	1148	Example: implement a custom write type C<join> that joins the remaining
1098	arguments using the first one.	1149	arguments using the first one.
1099		1150
…		…
1393	data.	1444	data.
1394		1445
1395	Example: read 2 bytes.	1446	Example: read 2 bytes.
1396		1447
1397	$handle->push_read (chunk => 2, sub {	1448	$handle->push_read (chunk => 2, sub {
1398	warn "yay ", unpack "H*", $_[1];	1449	say "yay " . unpack "H*", $_[1];
1399	});	1450	});
1400		1451
1401	=cut	1452	=cut
1402		1453
1403	register_read_type chunk => sub {	1454	register_read_type chunk => sub {
…		…
1437	if (@_ < 3) {	1488	if (@_ < 3) {
1438	# this is more than twice as fast as the generic code below	1489	# this is more than twice as fast as the generic code below
1439	sub {	1490	sub {
1440	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;	1491	$_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1441		1492
1442	$cb->($_[0], $1, $2);	1493	$cb->($_[0], "$1", "$2");
1443	1	1494	1
1444	}	1495	}
1445	} else {	1496	} else {
1446	$eol = quotemeta $eol unless ref $eol;	1497	$eol = quotemeta $eol unless ref $eol;
1447	$eol = qr\|^(.*?)($eol)\|s;	1498	$eol = qr\|^(.*?)($eol)\|s;
1448		1499
1449	sub {	1500	sub {
1450	$_[0]{rbuf} =~ s/$eol// or return;	1501	$_[0]{rbuf} =~ s/$eol// or return;
1451		1502
1452	$cb->($_[0], $1, $2);	1503	$cb->($_[0], "$1", "$2");
1453	1	1504	1
1454	}	1505	}
1455	}	1506	}
1456	};	1507	};
1457		1508
…		…
1505		1556
1506	sub {	1557	sub {
1507	# accept	1558	# accept
1508	if ($$rbuf =~ $accept) {	1559	if ($$rbuf =~ $accept) {
1509	$data .= substr $$rbuf, 0, $+[0], "";	1560	$data .= substr $$rbuf, 0, $+[0], "";
1510	$cb->($self, $data);	1561	$cb->($_[0], $data);
1511	return 1;	1562	return 1;
1512	}	1563	}
1513		1564
1514	# reject	1565	# reject
1515	if ($reject && $$rbuf =~ $reject) {	1566	if ($reject && $$rbuf =~ $reject) {
1516	$self->_error (Errno::EBADMSG);	1567	$_[0]->_error (Errno::EBADMSG);
1517	}	1568	}
1518		1569
1519	# skip	1570	# skip
1520	if ($skip && $$rbuf =~ $skip) {	1571	if ($skip && $$rbuf =~ $skip) {
1521	$data .= substr $$rbuf, 0, $+[0], "";	1572	$data .= substr $$rbuf, 0, $+[0], "";
…		…
1537	my ($self, $cb) = @_;	1588	my ($self, $cb) = @_;
1538		1589
1539	sub {	1590	sub {
1540	unless ($_[0]{rbuf} =~ s/^(0\|[1-9][0-9]*)://) {	1591	unless ($_[0]{rbuf} =~ s/^(0\|[1-9][0-9]*)://) {
1541	if ($_[0]{rbuf} =~ /[^0-9]/) {	1592	if ($_[0]{rbuf} =~ /[^0-9]/) {
1542	$self->_error (Errno::EBADMSG);	1593	$_[0]->_error (Errno::EBADMSG);
1543	}	1594	}
1544	return;	1595	return;
1545	}	1596	}
1546		1597
1547	my $len = $1;	1598	my $len = $1;
1548		1599
1549	$self->unshift_read (chunk => $len, sub {	1600	$_[0]->unshift_read (chunk => $len, sub {
1550	my $string = $_[1];	1601	my $string = $_[1];
1551	$_[0]->unshift_read (chunk => 1, sub {	1602	$_[0]->unshift_read (chunk => 1, sub {
1552	if ($_[1] eq ",") {	1603	if ($_[1] eq ",") {
1553	$cb->($_[0], $string);	1604	$cb->($_[0], $string);
1554	} else {	1605	} else {
1555	$self->_error (Errno::EBADMSG);	1606	$_[0]->_error (Errno::EBADMSG);
1556	}	1607	}
1557	});	1608	});
1558	});	1609	});
1559		1610
1560	1	1611	1
…		…
1633		1684
1634	my $data;	1685	my $data;
1635	my $rbuf = \$self->{rbuf};	1686	my $rbuf = \$self->{rbuf};
1636		1687
1637	sub {	1688	sub {
1638	my $ref = eval { $json->incr_parse ($self->{rbuf}) };	1689	my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1639		1690
1640	if ($ref) {	1691	if ($ref) {
1641	$self->{rbuf} = $json->incr_text;	1692	$_[0]{rbuf} = $json->incr_text;
1642	$json->incr_text = "";	1693	$json->incr_text = "";
1643	$cb->($self, $ref);	1694	$cb->($_[0], $ref);
1644		1695
1645	1	1696	1
1646	} elsif ($@) {	1697	} elsif ($@) {
1647	# error case	1698	# error case
1648	$json->incr_skip;	1699	$json->incr_skip;
1649		1700
1650	$self->{rbuf} = $json->incr_text;	1701	$_[0]{rbuf} = $json->incr_text;
1651	$json->incr_text = "";	1702	$json->incr_text = "";
1652		1703
1653	$self->_error (Errno::EBADMSG);	1704	$_[0]->_error (Errno::EBADMSG);
1654		1705
1655	()	1706	()
1656	} else {	1707	} else {
1657	$self->{rbuf} = "";	1708	$_[0]{rbuf} = "";
1658		1709
1659	()	1710	()
1660	}	1711	}
1661	}	1712	}
1662	};	1713	};
…		…
1672	=cut	1723	=cut
1673		1724
1674	register_read_type storable => sub {	1725	register_read_type storable => sub {
1675	my ($self, $cb) = @_;	1726	my ($self, $cb) = @_;
1676		1727
1677	require Storable;	1728	require Storable unless $Storable::VERSION;
1678		1729
1679	sub {	1730	sub {
1680	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method	1731	# when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1681	defined (my $len = eval { unpack "w", $_[0]{rbuf} })	1732	defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1682	or return;	1733	or return;
…		…
1685		1736
1686	# bypass unshift if we already have the remaining chunk	1737	# bypass unshift if we already have the remaining chunk
1687	if ($format + $len <= length $_[0]{rbuf}) {	1738	if ($format + $len <= length $_[0]{rbuf}) {
1688	my $data = substr $_[0]{rbuf}, $format, $len;	1739	my $data = substr $_[0]{rbuf}, $format, $len;
1689	substr $_[0]{rbuf}, 0, $format + $len, "";	1740	substr $_[0]{rbuf}, 0, $format + $len, "";
		1741
1690	$cb->($_[0], Storable::thaw ($data));	1742	eval { $cb->($_[0], Storable::thaw ($data)); 1 }
		1743	or return $_[0]->_error (Errno::EBADMSG);
1691	} else {	1744	} else {
1692	# remove prefix	1745	# remove prefix
1693	substr $_[0]{rbuf}, 0, $format, "";	1746	substr $_[0]{rbuf}, 0, $format, "";
1694		1747
1695	# read remaining chunk	1748	# read remaining chunk
1696	$_[0]->unshift_read (chunk => $len, sub {	1749	$_[0]->unshift_read (chunk => $len, sub {
1697	if (my $ref = eval { Storable::thaw ($_[1]) }) {	1750	eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1698	$cb->($_[0], $ref);
1699	} else {
1700	$self->_error (Errno::EBADMSG);	1751	or $_[0]->_error (Errno::EBADMSG);
1701	}
1702	});	1752	});
1703	}	1753	}
1704		1754
1705	1	1755	1
1706	}	1756	}
…		…
1743	Note that AnyEvent::Handle will automatically C<start_read> for you when	1793	Note that AnyEvent::Handle will automatically C<start_read> for you when
1744	you change the C<on_read> callback or push/unshift a read callback, and it	1794	you change the C<on_read> callback or push/unshift a read callback, and it
1745	will automatically C<stop_read> for you when neither C<on_read> is set nor	1795	will automatically C<stop_read> for you when neither C<on_read> is set nor
1746	there are any read requests in the queue.	1796	there are any read requests in the queue.
1747		1797
1748	These methods will have no effect when in TLS mode (as TLS doesn't support	1798	In older versions of this module (<= 5.3), these methods had no effect,
1749	half-duplex connections).	1799	as TLS does not support half-duplex connections. In current versions they
		1800	work as expected, as this behaviour is required to avoid certain resource
		1801	attacks, where the program would be forced to read (and buffer) arbitrary
		1802	amounts of data before being able to send some data. The drawback is that
		1803	some readings of the the SSL/TLS specifications basically require this
		1804	attack to be working, as SSL/TLS implementations might stall sending data
		1805	during a rehandshake.
		1806
		1807	As a guideline, during the initial handshake, you should not stop reading,
		1808	and as a client, it might cause problems, depending on your application.
1750		1809
1751	=cut	1810	=cut
1752		1811
1753	sub stop_read {	1812	sub stop_read {
1754	my ($self) = @_;	1813	my ($self) = @_;
1755		1814
1756	delete $self->{_rw} unless $self->{tls};	1815	delete $self->{_rw};
1757	}	1816	}
1758		1817
1759	sub start_read {	1818	sub start_read {
1760	my ($self) = @_;	1819	my ($self) = @_;
1761		1820
…		…
1802	my ($self, $err) = @_;	1861	my ($self, $err) = @_;
1803		1862
1804	return $self->_error ($!, 1)	1863	return $self->_error ($!, 1)
1805	if $err == Net::SSLeay::ERROR_SYSCALL ();	1864	if $err == Net::SSLeay::ERROR_SYSCALL ();
1806		1865
1807	my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());	1866	my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1808		1867
1809	# reduce error string to look less scary	1868	# reduce error string to look less scary
1810	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;	1869	$err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1811		1870
1812	if ($self->{_on_starttls}) {	1871	if ($self->{_on_starttls}) {
…		…
1963	Net::SSLeay::CTX_set_mode ($tls, 1\|2);	2022	Net::SSLeay::CTX_set_mode ($tls, 1\|2);
1964		2023
1965	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2024	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1966	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());	2025	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1967		2026
1968	Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf});	2027	Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
		2028	$self->{rbuf} = "";
1969		2029
1970	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});	2030	Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1971		2031
1972	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }	2032	$self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1973	if $self->{on_starttls};	2033	if $self->{on_starttls};
…		…
2010	$self->{tls_ctx}->_put_session (delete $self->{tls})	2070	$self->{tls_ctx}->_put_session (delete $self->{tls})
2011	if $self->{tls} > 0;	2071	if $self->{tls} > 0;
2012		2072
2013	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};	2073	delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2014	}	2074	}
		2075
		2076	=item $handle->resettls
		2077
		2078	This rarely-used method simply resets and TLS state on the handle, usually
		2079	causing data loss.
		2080
		2081	One case where it may be useful is when you want to skip over the data in
		2082	the stream but you are not interested in interpreting it, so data loss is
		2083	no concern.
		2084
		2085	=cut
		2086
		2087	*resettls = \&_freetls;
2015		2088
2016	sub DESTROY {	2089	sub DESTROY {
2017	my ($self) = @_;	2090	my ($self) = @_;
2018		2091
2019	&_freetls;	2092	&_freetls;
…		…
2135		2208
2136	It is only safe to "forget" the reference inside EOF or error callbacks,	2209	It is only safe to "forget" the reference inside EOF or error callbacks,
2137	from within all other callbacks, you need to explicitly call the C<<	2210	from within all other callbacks, you need to explicitly call the C<<
2138	->destroy >> method.	2211	->destroy >> method.
2139		2212
		2213	=item Why is my C<on_eof> callback never called?
		2214
		2215	Probably because your C<on_error> callback is being called instead: When
		2216	you have outstanding requests in your read queue, then an EOF is
		2217	considered an error as you clearly expected some data.
		2218
		2219	To avoid this, make sure you have an empty read queue whenever your handle
		2220	is supposed to be "idle" (i.e. connection closes are O.K.). You can set
		2221	an C<on_read> handler that simply pushes the first read requests in the
		2222	queue.
		2223
		2224	See also the next question, which explains this in a bit more detail.
		2225
		2226	=item How can I serve requests in a loop?
		2227
		2228	Most protocols consist of some setup phase (authentication for example)
		2229	followed by a request handling phase, where the server waits for requests
		2230	and handles them, in a loop.
		2231
		2232	There are two important variants: The first (traditional, better) variant
		2233	handles requests until the server gets some QUIT command, causing it to
		2234	close the connection first (highly desirable for a busy TCP server). A
		2235	client dropping the connection is an error, which means this variant can
		2236	detect an unexpected detection close.
		2237
		2238	To handle this case, always make sure you have a on-empty read queue, by
		2239	pushing the "read request start" handler on it:
		2240
		2241	# we assume a request starts with a single line
		2242	my @start_request; @start_request = (line => sub {
		2243	my ($hdl, $line) = @_;
		2244
		2245	... handle request
		2246
		2247	# push next request read, possibly from a nested callback
		2248	$hdl->push_read (@start_request);
		2249	});
		2250
		2251	# auth done, now go into request handling loop
		2252	# now push the first @start_request
		2253	$hdl->push_read (@start_request);
		2254
		2255	By always having an outstanding C<push_read>, the handle always expects
		2256	some data and raises the C<EPIPE> error when the connction is dropped
		2257	unexpectedly.
		2258
		2259	The second variant is a protocol where the client can drop the connection
		2260	at any time. For TCP, this means that the server machine may run out of
		2261	sockets easier, and in general, it means you cannot distinguish a protocl
		2262	failure/client crash from a normal connection close. Nevertheless, these
		2263	kinds of protocols are common (and sometimes even the best solution to the
		2264	problem).
		2265
		2266	Having an outstanding read request at all times is possible if you ignore
		2267	C<EPIPE> errors, but this doesn't help with when the client drops the
		2268	connection during a request, which would still be an error.
		2269
		2270	A better solution is to push the initial request read in an C<on_read>
		2271	callback. This avoids an error, as when the server doesn't expect data
		2272	(i.e. is idly waiting for the next request, an EOF will not raise an
		2273	error, but simply result in an C<on_eof> callback. It is also a bit slower
		2274	and simpler:
		2275
		2276	# auth done, now go into request handling loop
		2277	$hdl->on_read (sub {
		2278	my ($hdl) = @_;
		2279
		2280	# called each time we receive data but the read queue is empty
		2281	# simply start read the request
		2282
		2283	$hdl->push_read (line => sub {
		2284	my ($hdl, $line) = @_;
		2285
		2286	... handle request
		2287
		2288	# do nothing special when the request has been handled, just
		2289	# let the request queue go empty.
		2290	});
		2291	});
		2292
2140	=item I get different callback invocations in TLS mode/Why can't I pause	2293	=item I get different callback invocations in TLS mode/Why can't I pause
2141	reading?	2294	reading?
2142		2295
2143	Unlike, say, TCP, TLS connections do not consist of two independent	2296	Unlike, say, TCP, TLS connections do not consist of two independent
2144	communication channels, one for each direction. Or put differently, the	2297	communication channels, one for each direction. Or put differently, the
…		…
2165	$handle->on_eof (undef);	2318	$handle->on_eof (undef);
2166	$handle->on_error (sub {	2319	$handle->on_error (sub {
2167	my $data = delete $_[0]{rbuf};	2320	my $data = delete $_[0]{rbuf};
2168	});	2321	});
2169		2322
		2323	Note that this example removes the C<rbuf> member from the handle object,
		2324	which is not normally allowed by the API. It is expressly permitted in
		2325	this case only, as the handle object needs to be destroyed afterwards.
		2326
2170	The reason to use C<on_error> is that TCP connections, due to latencies	2327	The reason to use C<on_error> is that TCP connections, due to latencies
2171	and packets loss, might get closed quite violently with an error, when in	2328	and packets loss, might get closed quite violently with an error, when in
2172	fact all data has been received.	2329	fact all data has been received.
2173		2330
2174	It is usually better to use acknowledgements when transferring data,	2331	It is usually better to use acknowledgements when transferring data,
…		…
2184	C<low_water_mark> this will be called precisely when all data has been	2341	C<low_water_mark> this will be called precisely when all data has been
2185	written to the socket:	2342	written to the socket:
2186		2343
2187	$handle->push_write (...);	2344	$handle->push_write (...);
2188	$handle->on_drain (sub {	2345	$handle->on_drain (sub {
2189	warn "all data submitted to the kernel\n";	2346	AE::log debug => "All data submitted to the kernel.";
2190	undef $handle;	2347	undef $handle;
2191	});	2348	});
2192		2349
2193	If you just want to queue some data and then signal EOF to the other side,	2350	If you just want to queue some data and then signal EOF to the other side,
2194	consider using C<< ->push_shutdown >> instead.	2351	consider using C<< ->push_shutdown >> instead.
…		…
2278	When you have intermediate CA certificates that your clients might not	2435	When you have intermediate CA certificates that your clients might not
2279	know about, just append them to the C<cert_file>.	2436	know about, just append them to the C<cert_file>.
2280		2437
2281	=back	2438	=back
2282		2439
2283
2284	=head1 SUBCLASSING AnyEvent::Handle	2440	=head1 SUBCLASSING AnyEvent::Handle
2285		2441
2286	In many cases, you might want to subclass AnyEvent::Handle.	2442	In many cases, you might want to subclass AnyEvent::Handle.
2287		2443
2288	To make this easier, a given version of AnyEvent::Handle uses these	2444	To make this easier, a given version of AnyEvent::Handle uses these
…		…
2314		2470
2315	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	2471	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2316		2472
2317	=cut	2473	=cut
2318		2474
2319	1; # End of AnyEvent::Handle	2475	1
		2476

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.207 by root, Mon Nov 15 22:29:36 2010 UTC vs. Revision 1.233 by root, Thu Apr 5 06:14:10 2012 UTC

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.207 by root, Mon Nov 15 22:29:36 2010 UTC vs.
Revision 1.233 by root, Thu Apr 5 06:14:10 2012 UTC