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

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.8 by root, Fri May 2 15:36:10 2008 UTC vs.
Revision 1.42 by root, Tue May 27 06:23:15 2008 UTC

…		…
2		2
3	no warnings;	3	no warnings;
4	use strict;	4	use strict;
5		5
6	use AnyEvent ();	6	use AnyEvent ();
7	use AnyEvent::Util ();	7	use AnyEvent::Util qw(WSAEWOULDBLOCK);
8	use Scalar::Util ();	8	use Scalar::Util ();
9	use Carp ();	9	use Carp ();
10	use Fcntl ();	10	use Fcntl ();
11	use Errno qw/EAGAIN EINTR/;	11	use Errno qw/EAGAIN EINTR/;
12		12
13	=head1 NAME	13	=head1 NAME
14		14
15	AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent	15	AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16		16
17	=cut	17	=cut
18		18
19	our $VERSION = '0.02';	19	our $VERSION = '0.04';
20		20
21	=head1 SYNOPSIS	21	=head1 SYNOPSIS
22		22
23	use AnyEvent;	23	use AnyEvent;
24	use AnyEvent::Handle;	24	use AnyEvent::Handle;
25		25
26	my $cv = AnyEvent->condvar;	26	my $cv = AnyEvent->condvar;
27		27
28	my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN);	28	my $handle =
29
30	#TODO
31
32	# or use the constructor to pass the callback:
33
34	my $ae_fh2 =
35	AnyEvent::Handle->new (	29	AnyEvent::Handle->new (
36	fh => \*STDIN,	30	fh => \*STDIN,
37	on_eof => sub {	31	on_eof => sub {
38	$cv->broadcast;	32	$cv->broadcast;
39	},	33	},
40	#TODO
41	);	34	);
42		35
43	$cv->wait;	36	# send some request line
		37	$handle->push_write ("getinfo\015\012");
		38
		39	# read the response line
		40	$handle->push_read (line => sub {
		41	my ($handle, $line) = @_;
		42	warn "read line <$line>\n";
		43	$cv->send;
		44	});
		45
		46	$cv->recv;
44		47
45	=head1 DESCRIPTION	48	=head1 DESCRIPTION
46		49
47	This module is a helper module to make it easier to do event-based I/O on	50	This module is a helper module to make it easier to do event-based I/O on
48	filehandles (and sockets, see L<AnyEvent::Socket> for an easy way to make	51	filehandles. For utility functions for doing non-blocking connects and accepts
49	non-blocking resolves and connects).	52	on sockets see L<AnyEvent::Util>.
50		53
51	In the following, when the documentation refers to of "bytes" then this	54	In the following, when the documentation refers to of "bytes" then this
52	means characters. As sysread and syswrite are used for all I/O, their	55	means characters. As sysread and syswrite are used for all I/O, their
53	treatment of characters applies to this module as well.	56	treatment of characters applies to this module as well.
54		57
…		…
70	The filehandle this L<AnyEvent::Handle> object will operate on.	73	The filehandle this L<AnyEvent::Handle> object will operate on.
71		74
72	NOTE: The filehandle will be set to non-blocking (using	75	NOTE: The filehandle will be set to non-blocking (using
73	AnyEvent::Util::fh_nonblocking).	76	AnyEvent::Util::fh_nonblocking).
74		77
75	=item on_error => $cb->($self) [MANDATORY]	78	=item on_eof => $cb->($handle)
76		79
		80	Set the callback to be called on EOF.
		81
		82	While not mandatory, it is highly recommended to set an eof callback,
		83	otherwise you might end up with a closed socket while you are still
		84	waiting for data.
		85
		86	=item on_error => $cb->($handle)
		87
77	This is the fatal error callback, that is called when a fatal error ocurs,	88	This is the fatal error callback, that is called when, well, a fatal error
78	such as not being able to resolve the hostname, failure to connect or a	89	occurs, such as not being able to resolve the hostname, failure to connect
79	read error.	90	or a read error.
80		91
81	The object will not be in a usable state when this callback has been	92	The object will not be in a usable state when this callback has been
82	called.	93	called.
83		94
84	On callback entrance, the value of C<$!> contains the opertaing system	95	On callback entrance, the value of C<$!> contains the operating system
85	error (or C<ENOSPC> or C<EPIPE>).	96	error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).
86		97
87	=item on_eof => $cb->($self) [MANDATORY]	98	The callback should throw an exception. If it returns, then
		99	AnyEvent::Handle will C<croak> for you.
88		100
89	Set the callback to be called on EOF.	101	While not mandatory, it is I<highly> recommended to set this callback, as
		102	you will not be notified of errors otherwise. The default simply calls
		103	die.
90		104
91	=item on_read => $cb->($self)	105	=item on_read => $cb->($handle)
92		106
93	This sets the default read callback, which is called when data arrives	107	This sets the default read callback, which is called when data arrives
94	and no read request is in the queue. If the read callback is C<undef>	108	and no read request is in the queue.
95	or has never been set, than AnyEvent::Handle will cease reading from the
96	filehandle.
97		109
98	To access (and remove data from) the read buffer, use the C<< ->rbuf >>	110	To access (and remove data from) the read buffer, use the C<< ->rbuf >>
99	method or acces sthe C<$self->{rbuf}> member directly.	111	method or access the C<$handle->{rbuf}> member directly.
100		112
101	When an EOF condition is detected then AnyEvent::Handle will first try to	113	When an EOF condition is detected then AnyEvent::Handle will first try to
102	feed all the remaining data to the queued callbacks and C<on_read> before	114	feed all the remaining data to the queued callbacks and C<on_read> before
103	calling the C<on_eof> callback. If no progress can be made, then a fatal	115	calling the C<on_eof> callback. If no progress can be made, then a fatal
104	error will be raised (with C<$!> set to C<EPIPE>).	116	error will be raised (with C<$!> set to C<EPIPE>).
105		117
106	=item on_drain => $cb->()	118	=item on_drain => $cb->($handle)
107		119
108	This sets the callback that is called when the write buffer becomes empty	120	This sets the callback that is called when the write buffer becomes empty
109	(or when the callback is set and the buffer is empty already).	121	(or when the callback is set and the buffer is empty already).
110		122
111	To append to the write buffer, use the C<< ->push_write >> method.	123	To append to the write buffer, use the C<< ->push_write >> method.
…		…
131		143
132	Sets the amount of bytes (default: C<0>) that make up an "empty" write	144	Sets the amount of bytes (default: C<0>) that make up an "empty" write
133	buffer: If the write reaches this size or gets even samller it is	145	buffer: If the write reaches this size or gets even samller it is
134	considered empty.	146	considered empty.
135		147
		148	=item tls => "accept" \| "connect" \| Net::SSLeay::SSL object
		149
		150	When this parameter is given, it enables TLS (SSL) mode, that means it
		151	will start making tls handshake and will transparently encrypt/decrypt
		152	data.
		153
		154	TLS mode requires Net::SSLeay to be installed (it will be loaded
		155	automatically when you try to create a TLS handle).
		156
		157	For the TLS server side, use C<accept>, and for the TLS client side of a
		158	connection, use C<connect> mode.
		159
		160	You can also provide your own TLS connection object, but you have
		161	to make sure that you call either C<Net::SSLeay::set_connect_state>
		162	or C<Net::SSLeay::set_accept_state> on it before you pass it to
		163	AnyEvent::Handle.
		164
		165	See the C<starttls> method if you need to start TLs negotiation later.
		166
		167	=item tls_ctx => $ssl_ctx
		168
		169	Use the given Net::SSLeay::CTX object to create the new TLS connection
		170	(unless a connection object was specified directly). If this parameter is
		171	missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
		172
		173	=item json => JSON or JSON::XS object
		174
		175	This is the json coder object used by the C<json> read and write types.
		176
		177	If you don't supply it, then AnyEvent::Handle will create and use a
		178	suitable one, which will write and expect UTF-8 encoded JSON texts.
		179
		180	Note that you are responsible to depend on the JSON module if you want to
		181	use this functionality, as AnyEvent does not have a dependency itself.
		182
		183	=item filter_r => $cb
		184
		185	=item filter_w => $cb
		186
		187	These exist, but are undocumented at this time.
		188
136	=back	189	=back
137		190
138	=cut	191	=cut
139		192
140	sub new {	193	sub new {
…		…
144		197
145	$self->{fh} or Carp::croak "mandatory argument fh is missing";	198	$self->{fh} or Carp::croak "mandatory argument fh is missing";
146		199
147	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;	200	AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
148		201
149	$self->on_error ((delete $self->{on_error}) or Carp::croak "mandatory argument on_error is missing");	202	if ($self->{tls}) {
150	$self->on_eof ((delete $self->{on_eof} ) or Carp::croak "mandatory argument on_eof is missing");	203	require Net::SSLeay;
		204	$self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
		205	}
151		206
		207	$self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
		208	$self->on_error (delete $self->{on_error}) if $self->{on_error};
152	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};	209	$self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
153	$self->on_read (delete $self->{on_read} ) if $self->{on_read};	210	$self->on_read (delete $self->{on_read} ) if $self->{on_read};
154		211
		212	$self->start_read;
		213
155	$self	214	$self
156	}	215	}
157		216
158	sub _shutdown {	217	sub _shutdown {
159	my ($self) = @_;	218	my ($self) = @_;
160		219
161	delete $self->{rw};	220	delete $self->{_rw};
162	delete $self->{ww};	221	delete $self->{_ww};
163	delete $self->{fh};	222	delete $self->{fh};
164	}	223	}
165		224
166	sub error {	225	sub error {
167	my ($self) = @_;	226	my ($self) = @_;
…		…
169	{	228	{
170	local $!;	229	local $!;
171	$self->_shutdown;	230	$self->_shutdown;
172	}	231	}
173		232
174	$self->{on_error}($self);	233	$self->{on_error}($self)
		234	if $self->{on_error};
		235
		236	Carp::croak "AnyEvent::Handle uncaught fatal error: $!";
175	}	237	}
176		238
177	=item $fh = $handle->fh	239	=item $fh = $handle->fh
178		240
179	This method returns the filehandle of the L<AnyEvent::Handle> object.	241	This method returns the file handle of the L<AnyEvent::Handle> object.
180		242
181	=cut	243	=cut
182		244
183	sub fh { $_[0]->{fh} }	245	sub fh { $_[0]{fh} }
184		246
185	=item $handle->on_error ($cb)	247	=item $handle->on_error ($cb)
186		248
187	Replace the current C<on_error> callback (see the C<on_error> constructor argument).	249	Replace the current C<on_error> callback (see the C<on_error> constructor argument).
188		250
…		…
196		258
197	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).	259	Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
198		260
199	=cut	261	=cut
200		262
201	#############################################################################
202
203	sub on_eof {	263	sub on_eof {
204	$_[0]{on_eof} = $_[1];	264	$_[0]{on_eof} = $_[1];
205	}	265	}
		266
		267	#############################################################################
		268
		269	=back
		270
		271	=head2 WRITE QUEUE
		272
		273	AnyEvent::Handle manages two queues per handle, one for writing and one
		274	for reading.
		275
		276	The write queue is very simple: you can add data to its end, and
		277	AnyEvent::Handle will automatically try to get rid of it for you.
		278
		279	When data could be written and the write buffer is shorter then the low
		280	water mark, the C<on_drain> callback will be invoked.
		281
		282	=over 4
206		283
207	=item $handle->on_drain ($cb)	284	=item $handle->on_drain ($cb)
208		285
209	Sets the C<on_drain> callback or clears it (see the description of	286	Sets the C<on_drain> callback or clears it (see the description of
210	C<on_drain> in the constructor).	287	C<on_drain> in the constructor).
…		…
226	want (only limited by the available memory), as C<AnyEvent::Handle>	303	want (only limited by the available memory), as C<AnyEvent::Handle>
227	buffers it independently of the kernel.	304	buffers it independently of the kernel.
228		305
229	=cut	306	=cut
230		307
231	sub push_write {	308	sub _drain_wbuf {
232	my ($self, $data) = @_;	309	my ($self) = @_;
233		310
234	$self->{wbuf} .= $data;	311	if (!$self->{_ww} && length $self->{wbuf}) {
235		312
236	unless ($self->{ww}) {
237	Scalar::Util::weaken $self;	313	Scalar::Util::weaken $self;
		314
238	my $cb = sub {	315	my $cb = sub {
239	my $len = syswrite $self->{fh}, $self->{wbuf};	316	my $len = syswrite $self->{fh}, $self->{wbuf};
240		317
241	if ($len > 0) {	318	if ($len >= 0) {
242	substr $self->{wbuf}, 0, $len, "";	319	substr $self->{wbuf}, 0, $len, "";
243
244		320
245	$self->{on_drain}($self)	321	$self->{on_drain}($self)
246	if $self->{low_water_mark} >= length $self->{wbuf}	322	if $self->{low_water_mark} >= length $self->{wbuf}
247	&& $self->{on_drain};	323	&& $self->{on_drain};
248		324
249	delete $self->{ww} unless length $self->{wbuf};	325	delete $self->{_ww} unless length $self->{wbuf};
250	} elsif ($! != EAGAIN && $! != EINTR) {	326	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
251	$self->error;	327	$self->error;
252	}	328	}
253	};	329	};
254		330
		331	# try to write data immediately
		332	$cb->();
		333
		334	# if still data left in wbuf, we need to poll
255	$self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb);	335	$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
256		336	if length $self->{wbuf};
257	$cb->($self);
258	};	337	};
259	}	338	}
260		339
		340	our %WH;
		341
		342	sub register_write_type($$) {
		343	$WH{$_[0]} = $_[1];
		344	}
		345
		346	sub push_write {
		347	my $self = shift;
		348
		349	if (@_ > 1) {
		350	my $type = shift;
		351
		352	@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
		353	->($self, @_);
		354	}
		355
		356	if ($self->{filter_w}) {
		357	$self->{filter_w}->($self, \$_[0]);
		358	} else {
		359	$self->{wbuf} .= $_[0];
		360	$self->_drain_wbuf;
		361	}
		362	}
		363
		364	=item $handle->push_write (type => @args)
		365
		366	=item $handle->unshift_write (type => @args)
		367
		368	Instead of formatting your data yourself, you can also let this module do
		369	the job by specifying a type and type-specific arguments.
		370
		371	Predefined types are (if you have ideas for additional types, feel free to
		372	drop by and tell us):
		373
		374	=over 4
		375
		376	=item netstring => $string
		377
		378	Formats the given value as netstring
		379	(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
		380
		381	=back
		382
		383	=cut
		384
		385	register_write_type netstring => sub {
		386	my ($self, $string) = @_;
		387
		388	sprintf "%d:%s,", (length $string), $string
		389	};
		390
		391	=item json => $array_or_hashref
		392
		393	Encodes the given hash or array reference into a JSON object. Unless you
		394	provide your own JSON object, this means it will be encoded to JSON text
		395	in UTF-8.
		396
		397	JSON objects (and arrays) are self-delimiting, so you can write JSON at
		398	one end of a handle and read them at the other end without using any
		399	additional framing.
		400
		401	The generated JSON text is guaranteed not to contain any newlines: While
		402	this module doesn't need delimiters after or between JSON texts to be
		403	able to read them, many other languages depend on that.
		404
		405	A simple RPC protocol that interoperates easily with others is to send
		406	JSON arrays (or objects, although arrays are usually the better choice as
		407	they mimic how function argument passing works) and a newline after each
		408	JSON text:
		409
		410	$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
		411	$handle->push_write ("\012");
		412
		413	An AnyEvent::Handle receiver would simply use the C<json> read type and
		414	rely on the fact that the newline will be skipped as leading whitespace:
		415
		416	$handle->push_read (json => sub { my $array = $_[1]; ... });
		417
		418	Other languages could read single lines terminated by a newline and pass
		419	this line into their JSON decoder of choice.
		420
		421	=cut
		422
		423	register_write_type json => sub {
		424	my ($self, $ref) = @_;
		425
		426	require JSON;
		427
		428	$self->{json} ? $self->{json}->encode ($ref)
		429	: JSON::encode_json ($ref)
		430	};
		431
		432	=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
		433
		434	This function (not method) lets you add your own types to C<push_write>.
		435	Whenever the given C<type> is used, C<push_write> will invoke the code
		436	reference with the handle object and the remaining arguments.
		437
		438	The code reference is supposed to return a single octet string that will
		439	be appended to the write buffer.
		440
		441	Note that this is a function, and all types registered this way will be
		442	global, so try to use unique names.
		443
		444	=cut
		445
261	#############################################################################	446	#############################################################################
		447
		448	=back
		449
		450	=head2 READ QUEUE
		451
		452	AnyEvent::Handle manages two queues per handle, one for writing and one
		453	for reading.
		454
		455	The read queue is more complex than the write queue. It can be used in two
		456	ways, the "simple" way, using only C<on_read> and the "complex" way, using
		457	a queue.
		458
		459	In the simple case, you just install an C<on_read> callback and whenever
		460	new data arrives, it will be called. You can then remove some data (if
		461	enough is there) from the read buffer (C<< $handle->rbuf >>) if you want
		462	or not.
		463
		464	In the more complex case, you want to queue multiple callbacks. In this
		465	case, AnyEvent::Handle will call the first queued callback each time new
		466	data arrives and removes it when it has done its job (see C<push_read>,
		467	below).
		468
		469	This way you can, for example, push three line-reads, followed by reading
		470	a chunk of data, and AnyEvent::Handle will execute them in order.
		471
		472	Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
		473	the specified number of bytes which give an XML datagram.
		474
		475	# in the default state, expect some header bytes
		476	$handle->on_read (sub {
		477	# some data is here, now queue the length-header-read (4 octets)
		478	shift->unshift_read_chunk (4, sub {
		479	# header arrived, decode
		480	my $len = unpack "N", $_[1];
		481
		482	# now read the payload
		483	shift->unshift_read_chunk ($len, sub {
		484	my $xml = $_[1];
		485	# handle xml
		486	});
		487	});
		488	});
		489
		490	Example 2: Implement a client for a protocol that replies either with
		491	"OK" and another line or "ERROR" for one request, and 64 bytes for the
		492	second request. Due tot he availability of a full queue, we can just
		493	pipeline sending both requests and manipulate the queue as necessary in
		494	the callbacks:
		495
		496	# request one
		497	$handle->push_write ("request 1\015\012");
		498
		499	# we expect "ERROR" or "OK" as response, so push a line read
		500	$handle->push_read_line (sub {
		501	# if we got an "OK", we have to _prepend_ another line,
		502	# so it will be read before the second request reads its 64 bytes
		503	# which are already in the queue when this callback is called
		504	# we don't do this in case we got an error
		505	if ($_[1] eq "OK") {
		506	$_[0]->unshift_read_line (sub {
		507	my $response = $_[1];
		508	...
		509	});
		510	}
		511	});
		512
		513	# request two
		514	$handle->push_write ("request 2\015\012");
		515
		516	# simply read 64 bytes, always
		517	$handle->push_read_chunk (64, sub {
		518	my $response = $_[1];
		519	...
		520	});
		521
		522	=over 4
		523
		524	=cut
262		525
263	sub _drain_rbuf {	526	sub _drain_rbuf {
264	my ($self) = @_;	527	my ($self) = @_;
265		528
		529	if (
		530	defined $self->{rbuf_max}
		531	&& $self->{rbuf_max} < length $self->{rbuf}
		532	) {
		533	$! = &Errno::ENOSPC;
		534	$self->error;
		535	}
		536
266	return if exists $self->{in_drain};	537	return if $self->{in_drain};
267	local $self->{in_drain} = 1;	538	local $self->{in_drain} = 1;
268		539
269	while (my $len = length $self->{rbuf}) {	540	while (my $len = length $self->{rbuf}) {
270	no strict 'refs';	541	no strict 'refs';
271	if (@{ $self->{queue} }) {	542	if (my $cb = shift @{ $self->{_queue} }) {
272	if ($self->{queue}[0]($self)) {	543	unless ($cb->($self)) {
273	shift @{ $self->{queue} };
274	} elsif ($self->{eof}) {	544	if ($self->{_eof}) {
275	# no progress can be made (not enough data and no data forthcoming)	545	# no progress can be made (not enough data and no data forthcoming)
276	$! = &Errno::EPIPE; return $self->error;	546	$! = &Errno::EPIPE;
277	} else {	547	$self->error;
		548	}
		549
		550	unshift @{ $self->{_queue} }, $cb;
278	return;	551	return;
279	}	552	}
280	} elsif ($self->{on_read}) {	553	} elsif ($self->{on_read}) {
281	$self->{on_read}($self);	554	$self->{on_read}($self);
282		555
283	if (	556	if (
284	$self->{eof} # if no further data will arrive	557	$self->{_eof} # if no further data will arrive
285	&& $len == length $self->{rbuf} # and no data has been consumed	558	&& $len == length $self->{rbuf} # and no data has been consumed
286	&& !@{ $self->{queue} } # and the queue is still empty	559	&& !@{ $self->{_queue} } # and the queue is still empty
287	&& $self->{on_read} # and we still want to read data	560	&& $self->{on_read} # and we still want to read data
288	) {	561	) {
289	# then no progress can be made	562	# then no progress can be made
290	$! = &Errno::EPIPE; return $self->error;	563	$! = &Errno::EPIPE;
		564	$self->error;
291	}	565	}
292	} else {	566	} else {
293	# read side becomes idle	567	# read side becomes idle
294	delete $self->{rw};	568	delete $self->{_rw};
295	return;	569	return;
296	}	570	}
297	}	571	}
298		572
299	if ($self->{eof}) {	573	if ($self->{_eof}) {
300	$self->_shutdown;	574	$self->_shutdown;
301	$self->{on_eof}($self);	575	$self->{on_eof}($self)
		576	if $self->{on_eof};
302	}	577	}
303	}	578	}
304		579
305	=item $handle->on_read ($cb)	580	=item $handle->on_read ($cb)
306		581
…		…
312		587
313	sub on_read {	588	sub on_read {
314	my ($self, $cb) = @_;	589	my ($self, $cb) = @_;
315		590
316	$self->{on_read} = $cb;	591	$self->{on_read} = $cb;
317
318	unless ($self->{rw} \|\| $self->{eof}) {
319	Scalar::Util::weaken $self;
320
321	$self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
322	my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} \|\| 8192, length $self->{rbuf};
323
324	if ($len > 0) {
325	if (exists $self->{rbuf_max}) {
326	if ($self->{rbuf_max} < length $self->{rbuf}) {
327	$! = &Errno::ENOSPC; return $self->error;
328	}
329	}
330
331	} elsif (defined $len) {
332	$self->{eof} = 1;
333	delete $self->{rw};
334
335	} elsif ($! != EAGAIN && $! != EINTR) {
336	return $self->error;
337	}
338
339	$self->_drain_rbuf;
340	});
341	}
342	}	592	}
343		593
344	=item $handle->rbuf	594	=item $handle->rbuf
345		595
346	Returns the read buffer (as a modifiable lvalue).	596	Returns the read buffer (as a modifiable lvalue).
…		…
365	Append the given callback to the end of the queue (C<push_read>) or	615	Append the given callback to the end of the queue (C<push_read>) or
366	prepend it (C<unshift_read>).	616	prepend it (C<unshift_read>).
367		617
368	The callback is called each time some additional read data arrives.	618	The callback is called each time some additional read data arrives.
369		619
370	It must check wether enough data is in the read buffer already.	620	It must check whether enough data is in the read buffer already.
371		621
372	If not enough data is available, it must return the empty list or a false	622	If not enough data is available, it must return the empty list or a false
373	value, in which case it will be called repeatedly until enough data is	623	value, in which case it will be called repeatedly until enough data is
374	available (or an error condition is detected).	624	available (or an error condition is detected).
375		625
…		…
377	interested in (which can be none at all) and return a true value. After returning	627	interested in (which can be none at all) and return a true value. After returning
378	true, it will be removed from the queue.	628	true, it will be removed from the queue.
379		629
380	=cut	630	=cut
381		631
		632	our %RH;
		633
		634	sub register_read_type($$) {
		635	$RH{$_[0]} = $_[1];
		636	}
		637
382	sub push_read {	638	sub push_read {
383	my ($self, $cb) = @_;	639	my $self = shift;
		640	my $cb = pop;
384		641
		642	if (@_) {
		643	my $type = shift;
		644
		645	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
		646	->($self, $cb, @_);
		647	}
		648
385	push @{ $self->{queue} }, $cb;	649	push @{ $self->{_queue} }, $cb;
386	$self->_drain_rbuf;	650	$self->_drain_rbuf;
387	}	651	}
388		652
389	sub unshift_read {	653	sub unshift_read {
390	my ($self, $cb) = @_;	654	my $self = shift;
		655	my $cb = pop;
391		656
		657	if (@_) {
		658	my $type = shift;
		659
		660	$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
		661	->($self, $cb, @_);
		662	}
		663
		664
392	push @{ $self->{queue} }, $cb;	665	unshift @{ $self->{_queue} }, $cb;
393	$self->_drain_rbuf;	666	$self->_drain_rbuf;
394	}	667	}
395		668
396	=item $handle->push_read_chunk ($len, $cb->($self, $data))	669	=item $handle->push_read (type => @args, $cb)
397		670
398	=item $handle->unshift_read_chunk ($len, $cb->($self, $data))	671	=item $handle->unshift_read (type => @args, $cb)
399		672
400	Append the given callback to the end of the queue (C<push_read_chunk>) or	673	Instead of providing a callback that parses the data itself you can chose
401	prepend it (C<unshift_read_chunk>).	674	between a number of predefined parsing formats, for chunks of data, lines
		675	etc.
402		676
403	The callback will be called only once C<$len> bytes have been read, and	677	Predefined types are (if you have ideas for additional types, feel free to
404	these C<$len> bytes will be passed to the callback.	678	drop by and tell us):
405		679
406	=cut	680	=over 4
407		681
408	sub _read_chunk($$) {	682	=item chunk => $octets, $cb->($handle, $data)
409	my ($len, $cb) = @_;	683
		684	Invoke the callback only once C<$octets> bytes have been read. Pass the
		685	data read to the callback. The callback will never be called with less
		686	data.
		687
		688	Example: read 2 bytes.
		689
		690	$handle->push_read (chunk => 2, sub {
		691	warn "yay ", unpack "H*", $_[1];
		692	});
		693
		694	=cut
		695
		696	register_read_type chunk => sub {
		697	my ($self, $cb, $len) = @_;
410		698
411	sub {	699	sub {
412	$len <= length $_[0]{rbuf} or return;	700	$len <= length $_[0]{rbuf} or return;
413	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");	701	$cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
414	1	702	1
415	}	703	}
416	}	704	};
417		705
		706	# compatibility with older API
418	sub push_read_chunk {	707	sub push_read_chunk {
419	my ($self, $len, $cb) = @_;	708	$_[0]->push_read (chunk => $_[1], $_[2]);
420
421	$self->push_read (_read_chunk $len, $cb);
422	}	709	}
423
424		710
425	sub unshift_read_chunk {	711	sub unshift_read_chunk {
426	my ($self, $len, $cb) = @_;	712	$_[0]->unshift_read (chunk => $_[1], $_[2]);
427
428	$self->unshift_read (_read_chunk $len, $cb);
429	}	713	}
430		714
431	=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))	715	=item line => [$eol, ]$cb->($handle, $line, $eol)
432
433	=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
434
435	Append the given callback to the end of the queue (C<push_read_line>) or
436	prepend it (C<unshift_read_line>).
437		716
438	The callback will be called only once a full line (including the end of	717	The callback will be called only once a full line (including the end of
439	line marker, C<$eol>) has been read. This line (excluding the end of line	718	line marker, C<$eol>) has been read. This line (excluding the end of line
440	marker) will be passed to the callback as second argument (C<$line>), and	719	marker) will be passed to the callback as second argument (C<$line>), and
441	the end of line marker as the third argument (C<$eol>).	720	the end of line marker as the third argument (C<$eol>).
…		…
452	Partial lines at the end of the stream will never be returned, as they are	731	Partial lines at the end of the stream will never be returned, as they are
453	not marked by the end of line marker.	732	not marked by the end of line marker.
454		733
455	=cut	734	=cut
456		735
457	sub _read_line($$) {	736	register_read_type line => sub {
458	my $cb = pop;	737	my ($self, $cb, $eol) = @_;
459	my $eol = @_ ? shift : qr\|(\015?\012)\|;
460	my $pos;
461		738
		739	$eol = qr\|(\015?\012)\| if @_ < 3;
462	$eol = qr\|(\Q$eol\E)\| unless ref $eol;	740	$eol = quotemeta $eol unless ref $eol;
463	$eol = qr\|^(.*?)($eol)\|;	741	$eol = qr\|^(.*?)($eol)\|s;
464		742
465	sub {	743	sub {
466	$_[0]{rbuf} =~ s/$eol// or return;	744	$_[0]{rbuf} =~ s/$eol// or return;
467		745
468	$cb->($1, $2);	746	$cb->($_[0], $1, $2);
469	1	747	1
470	}	748	}
471	}	749	};
472		750
		751	# compatibility with older API
473	sub push_read_line {	752	sub push_read_line {
474	my $self = shift;	753	my $self = shift;
475
476	$self->push_read (&_read_line);	754	$self->push_read (line => @_);
477	}	755	}
478		756
479	sub unshift_read_line {	757	sub unshift_read_line {
480	my $self = shift;	758	my $self = shift;
481
482	$self->unshift_read (&_read_line);	759	$self->unshift_read (line => @_);
483	}	760	}
		761
		762	=item netstring => $cb->($handle, $string)
		763
		764	A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
		765
		766	Throws an error with C<$!> set to EBADMSG on format violations.
		767
		768	=cut
		769
		770	register_read_type netstring => sub {
		771	my ($self, $cb) = @_;
		772
		773	sub {
		774	unless ($_[0]{rbuf} =~ s/^(0\|[1-9][0-9]*)://) {
		775	if ($_[0]{rbuf} =~ /[^0-9]/) {
		776	$! = &Errno::EBADMSG;
		777	$self->error;
		778	}
		779	return;
		780	}
		781
		782	my $len = $1;
		783
		784	$self->unshift_read (chunk => $len, sub {
		785	my $string = $_[1];
		786	$_[0]->unshift_read (chunk => 1, sub {
		787	if ($_[1] eq ",") {
		788	$cb->($_[0], $string);
		789	} else {
		790	$! = &Errno::EBADMSG;
		791	$self->error;
		792	}
		793	});
		794	});
		795
		796	1
		797	}
		798	};
		799
		800	=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
		801
		802	Makes a regex match against the regex object C<$accept> and returns
		803	everything up to and including the match.
		804
		805	Example: read a single line terminated by '\n'.
		806
		807	$handle->push_read (regex => qr<\n>, sub { ... });
		808
		809	If C<$reject> is given and not undef, then it determines when the data is
		810	to be rejected: it is matched against the data when the C<$accept> regex
		811	does not match and generates an C<EBADMSG> error when it matches. This is
		812	useful to quickly reject wrong data (to avoid waiting for a timeout or a
		813	receive buffer overflow).
		814
		815	Example: expect a single decimal number followed by whitespace, reject
		816	anything else (not the use of an anchor).
		817
		818	$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
		819
		820	If C<$skip> is given and not C<undef>, then it will be matched against
		821	the receive buffer when neither C<$accept> nor C<$reject> match,
		822	and everything preceding and including the match will be accepted
		823	unconditionally. This is useful to skip large amounts of data that you
		824	know cannot be matched, so that the C<$accept> or C<$reject> regex do not
		825	have to start matching from the beginning. This is purely an optimisation
		826	and is usually worth only when you expect more than a few kilobytes.
		827
		828	Example: expect a http header, which ends at C<\015\012\015\012>. Since we
		829	expect the header to be very large (it isn't in practise, but...), we use
		830	a skip regex to skip initial portions. The skip regex is tricky in that
		831	it only accepts something not ending in either \015 or \012, as these are
		832	required for the accept regex.
		833
		834	$handle->push_read (regex =>
		835	qr<\015\012\015\012>,
		836	undef, # no reject
		837	qr<^.*[^\015\012]>,
		838	sub { ... });
		839
		840	=cut
		841
		842	register_read_type regex => sub {
		843	my ($self, $cb, $accept, $reject, $skip) = @_;
		844
		845	my $data;
		846	my $rbuf = \$self->{rbuf};
		847
		848	sub {
		849	# accept
		850	if ($$rbuf =~ $accept) {
		851	$data .= substr $$rbuf, 0, $+[0], "";
		852	$cb->($self, $data);
		853	return 1;
		854	}
		855
		856	# reject
		857	if ($reject && $$rbuf =~ $reject) {
		858	$! = &Errno::EBADMSG;
		859	$self->error;
		860	}
		861
		862	# skip
		863	if ($skip && $$rbuf =~ $skip) {
		864	$data .= substr $$rbuf, 0, $+[0], "";
		865	}
		866
		867	()
		868	}
		869	};
		870
		871	=item json => $cb->($handle, $hash_or_arrayref)
		872
		873	Reads a JSON object or array, decodes it and passes it to the callback.
		874
		875	If a C<json> object was passed to the constructor, then that will be used
		876	for the final decode, otherwise it will create a JSON coder expecting UTF-8.
		877
		878	This read type uses the incremental parser available with JSON version
		879	2.09 (and JSON::XS version 2.2) and above. You have to provide a
		880	dependency on your own: this module will load the JSON module, but
		881	AnyEvent does not depend on it itself.
		882
		883	Since JSON texts are fully self-delimiting, the C<json> read and write
		884	types are an ideal simple RPC protocol: just exchange JSON datagrams. See
		885	the C<json> write type description, above, for an actual example.
		886
		887	=cut
		888
		889	register_read_type json => sub {
		890	my ($self, $cb, $accept, $reject, $skip) = @_;
		891
		892	require JSON;
		893
		894	my $data;
		895	my $rbuf = \$self->{rbuf};
		896
		897	my $json = $self->{json} \|\|= JSON->new->utf8;
		898
		899	sub {
		900	my $ref = $json->incr_parse ($self->{rbuf});
		901
		902	if ($ref) {
		903	$self->{rbuf} = $json->incr_text;
		904	$json->incr_text = "";
		905	$cb->($self, $ref);
		906
		907	1
		908	} else {
		909	$self->{rbuf} = "";
		910	()
		911	}
		912	}
		913	};
484		914
485	=back	915	=back
486		916
		917	=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
		918
		919	This function (not method) lets you add your own types to C<push_read>.
		920
		921	Whenever the given C<type> is used, C<push_read> will invoke the code
		922	reference with the handle object, the callback and the remaining
		923	arguments.
		924
		925	The code reference is supposed to return a callback (usually a closure)
		926	that works as a plain read callback (see C<< ->push_read ($cb) >>).
		927
		928	It should invoke the passed callback when it is done reading (remember to
		929	pass C<$handle> as first argument as all other callbacks do that).
		930
		931	Note that this is a function, and all types registered this way will be
		932	global, so try to use unique names.
		933
		934	For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
		935	search for C<register_read_type>)).
		936
		937	=item $handle->stop_read
		938
		939	=item $handle->start_read
		940
		941	In rare cases you actually do not want to read anything from the
		942	socket. In this case you can call C<stop_read>. Neither C<on_read> no
		943	any queued callbacks will be executed then. To start reading again, call
		944	C<start_read>.
		945
		946	=cut
		947
		948	sub stop_read {
		949	my ($self) = @_;
		950
		951	delete $self->{_rw};
		952	}
		953
		954	sub start_read {
		955	my ($self) = @_;
		956
		957	unless ($self->{_rw} \|\| $self->{_eof}) {
		958	Scalar::Util::weaken $self;
		959
		960	$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
		961	my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
		962	my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} \|\| 8192, length $$rbuf;
		963
		964	if ($len > 0) {
		965	$self->{filter_r}
		966	? $self->{filter_r}->($self, $rbuf)
		967	: $self->_drain_rbuf;
		968
		969	} elsif (defined $len) {
		970	delete $self->{_rw};
		971	$self->{_eof} = 1;
		972	$self->_drain_rbuf;
		973
		974	} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
		975	return $self->error;
		976	}
		977	});
		978	}
		979	}
		980
		981	sub _dotls {
		982	my ($self) = @_;
		983
		984	if (length $self->{_tls_wbuf}) {
		985	while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
		986	substr $self->{_tls_wbuf}, 0, $len, "";
		987	}
		988	}
		989
		990	if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
		991	$self->{wbuf} .= $buf;
		992	$self->_drain_wbuf;
		993	}
		994
		995	while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
		996	$self->{rbuf} .= $buf;
		997	$self->_drain_rbuf;
		998	}
		999
		1000	my $err = Net::SSLeay::get_error ($self->{tls}, -1);
		1001
		1002	if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
		1003	if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
		1004	$self->error;
		1005	} elsif ($err == Net::SSLeay::ERROR_SSL ()) {
		1006	$! = &Errno::EIO;
		1007	$self->error;
		1008	}
		1009
		1010	# all others are fine for our purposes
		1011	}
		1012	}
		1013
		1014	=item $handle->starttls ($tls[, $tls_ctx])
		1015
		1016	Instead of starting TLS negotiation immediately when the AnyEvent::Handle
		1017	object is created, you can also do that at a later time by calling
		1018	C<starttls>.
		1019
		1020	The first argument is the same as the C<tls> constructor argument (either
		1021	C<"connect">, C<"accept"> or an existing Net::SSLeay object).
		1022
		1023	The second argument is the optional C<Net::SSLeay::CTX> object that is
		1024	used when AnyEvent::Handle has to create its own TLS connection object.
		1025
		1026	The TLS connection object will end up in C<< $handle->{tls} >> after this
		1027	call and can be used or changed to your liking. Note that the handshake
		1028	might have already started when this function returns.
		1029
		1030	=cut
		1031
		1032	# TODO: maybe document...
		1033	sub starttls {
		1034	my ($self, $ssl, $ctx) = @_;
		1035
		1036	$self->stoptls;
		1037
		1038	if ($ssl eq "accept") {
		1039	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
		1040	Net::SSLeay::set_accept_state ($ssl);
		1041	} elsif ($ssl eq "connect") {
		1042	$ssl = Net::SSLeay::new ($ctx \|\| TLS_CTX ());
		1043	Net::SSLeay::set_connect_state ($ssl);
		1044	}
		1045
		1046	$self->{tls} = $ssl;
		1047
		1048	# basically, this is deep magic (because SSL_read should have the same issues)
		1049	# but the openssl maintainers basically said: "trust us, it just works".
		1050	# (unfortunately, we have to hardcode constants because the abysmally misdesigned
		1051	# and mismaintained ssleay-module doesn't even offer them).
		1052	# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
		1053	Net::SSLeay::CTX_set_mode ($self->{tls},
		1054	(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } \|\| 1)
		1055	\| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } \|\| 2));
		1056
		1057	$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1058	$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
		1059
		1060	Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
		1061
		1062	$self->{filter_w} = sub {
		1063	$_[0]{_tls_wbuf} .= ${$_[1]};
		1064	&_dotls;
		1065	};
		1066	$self->{filter_r} = sub {
		1067	Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
		1068	&_dotls;
		1069	};
		1070	}
		1071
		1072	=item $handle->stoptls
		1073
		1074	Destroys the SSL connection, if any. Partial read or write data will be
		1075	lost.
		1076
		1077	=cut
		1078
		1079	sub stoptls {
		1080	my ($self) = @_;
		1081
		1082	Net::SSLeay::free (delete $self->{tls}) if $self->{tls};
		1083
		1084	delete $self->{_rbio};
		1085	delete $self->{_wbio};
		1086	delete $self->{_tls_wbuf};
		1087	delete $self->{filter_r};
		1088	delete $self->{filter_w};
		1089	}
		1090
		1091	sub DESTROY {
		1092	my $self = shift;
		1093
		1094	$self->stoptls;
		1095	}
		1096
		1097	=item AnyEvent::Handle::TLS_CTX
		1098
		1099	This function creates and returns the Net::SSLeay::CTX object used by
		1100	default for TLS mode.
		1101
		1102	The context is created like this:
		1103
		1104	Net::SSLeay::load_error_strings;
		1105	Net::SSLeay::SSLeay_add_ssl_algorithms;
		1106	Net::SSLeay::randomize;
		1107
		1108	my $CTX = Net::SSLeay::CTX_new;
		1109
		1110	Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
		1111
		1112	=cut
		1113
		1114	our $TLS_CTX;
		1115
		1116	sub TLS_CTX() {
		1117	$TLS_CTX \|\| do {
		1118	require Net::SSLeay;
		1119
		1120	Net::SSLeay::load_error_strings ();
		1121	Net::SSLeay::SSLeay_add_ssl_algorithms ();
		1122	Net::SSLeay::randomize ();
		1123
		1124	$TLS_CTX = Net::SSLeay::CTX_new ();
		1125
		1126	Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
		1127
		1128	$TLS_CTX
		1129	}
		1130	}
		1131
		1132	=back
		1133
		1134	=head1 SUBCLASSING AnyEvent::Handle
		1135
		1136	In many cases, you might want to subclass AnyEvent::Handle.
		1137
		1138	To make this easier, a given version of AnyEvent::Handle uses these
		1139	conventions:
		1140
		1141	=over 4
		1142
		1143	=item * all constructor arguments become object members.
		1144
		1145	At least initially, when you pass a C<tls>-argument to the constructor it
		1146	will end up in C<< $handle->{tls} >>. Those members might be changes or
		1147	mutated later on (for example C<tls> will hold the TLS connection object).
		1148
		1149	=item * other object member names are prefixed with an C<_>.
		1150
		1151	All object members not explicitly documented (internal use) are prefixed
		1152	with an underscore character, so the remaining non-C<_>-namespace is free
		1153	for use for subclasses.
		1154
		1155	=item * all members not documented here and not prefixed with an underscore
		1156	are free to use in subclasses.
		1157
		1158	Of course, new versions of AnyEvent::Handle may introduce more "public"
		1159	member variables, but thats just life, at least it is documented.
		1160
		1161	=back
		1162
487	=head1 AUTHOR	1163	=head1 AUTHOR
488		1164
489	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.	1165	Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
490		1166
491	=cut	1167	=cut

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.8 by root, Fri May 2 15:36:10 2008 UTC vs. Revision 1.42 by root, Tue May 27 06:23:15 2008 UTC

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.8 by root, Fri May 2 15:36:10 2008 UTC vs.
Revision 1.42 by root, Tue May 27 06:23:15 2008 UTC