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Revision 1.237 by root, Tue Jul 30 23:14:32 2013 UTC

1package AnyEvent::Handle;
2
3no warnings;
4use strict;
5
6use AnyEvent ();
7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util ();
9use Carp ();
10use Fcntl ();
11use Errno qw/EAGAIN EINTR/;
12
13=head1 NAME 1=head1 NAME
14 2
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17=cut
18
19our $VERSION = '0.04';
20 4
21=head1 SYNOPSIS 5=head1 SYNOPSIS
22 6
23 use AnyEvent; 7 use AnyEvent;
24 use AnyEvent::Handle; 8 use AnyEvent::Handle;
25 9
26 my $cv = AnyEvent->condvar; 10 my $cv = AnyEvent->condvar;
27 11
28 my $handle = 12 my $hdl; $hdl = new AnyEvent::Handle
29 AnyEvent::Handle->new (
30 fh => \*STDIN, 13 fh => \*STDIN,
31 on_eof => sub { 14 on_error => sub {
32 $cv->broadcast; 15 my ($hdl, $fatal, $msg) = @_;
33 }, 16 AE::log error => $msg;
17 $hdl->destroy;
18 $cv->send;
34 ); 19 };
35 20
36 # send some request line 21 # send some request line
37 $handle->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
38 23
39 # read the response line 24 # read the response line
40 $handle->push_read (line => sub { 25 $hdl->push_read (line => sub {
41 my ($handle, $line) = @_; 26 my ($hdl, $line) = @_;
42 warn "read line <$line>\n"; 27 say "got line <$line>";
43 $cv->send; 28 $cv->send;
44 }); 29 });
45 30
46 $cv->recv; 31 $cv->recv;
47 32
48=head1 DESCRIPTION 33=head1 DESCRIPTION
49 34
50This module is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O on
51filehandles. For utility functions for doing non-blocking connects and accepts 36stream-based filehandles (sockets, pipes, and other stream things).
52on sockets see L<AnyEvent::Util>.
53 37
38The L<AnyEvent::Intro> tutorial contains some well-documented
39AnyEvent::Handle examples.
40
54In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
55means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
56treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44
45At the very minimum, you should specify C<fh> or C<connect>, and the
46C<on_error> callback.
57 47
58All callbacks will be invoked with the handle object as their first 48All callbacks will be invoked with the handle object as their first
59argument. 49argument.
60 50
51=cut
52
53package AnyEvent::Handle;
54
55use Scalar::Util ();
56use List::Util ();
57use Carp ();
58use Errno qw(EAGAIN EINTR);
59
60use AnyEvent (); BEGIN { AnyEvent::common_sense }
61use AnyEvent::Util qw(WSAEWOULDBLOCK);
62
63our $VERSION = $AnyEvent::VERSION;
64
65sub _load_func($) {
66 my $func = $_[0];
67
68 unless (defined &$func) {
69 my $pkg = $func;
70 do {
71 $pkg =~ s/::[^:]+$//
72 or return;
73 eval "require $pkg";
74 } until defined &$func;
75 }
76
77 \&$func
78}
79
80sub MAX_READ_SIZE() { 131072 }
81
61=head1 METHODS 82=head1 METHODS
62 83
63=over 4 84=over 4
64 85
65=item B<new (%args)> 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
66 87
67The constructor supports these arguments (all as key => value pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
68 89
69=over 4 90=over 4
70 91
71=item fh => $filehandle [MANDATORY] 92=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
72 93
73The filehandle this L<AnyEvent::Handle> object will operate on. 94The filehandle this L<AnyEvent::Handle> object will operate on.
74
75NOTE: The filehandle will be set to non-blocking (using 95NOTE: The filehandle will be set to non-blocking mode (using
76AnyEvent::Util::fh_nonblocking). 96C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
97that mode.
77 98
78=item on_eof => $cb->($handle) 99=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
79 100
80Set the callback to be called on EOF. 101Try to connect to the specified host and service (port), using
102C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
103default C<peername>.
81 104
82While not mandatory, it is highly recommended to set an eof callback, 105You have to specify either this parameter, or C<fh>, above.
83otherwise you might end up with a closed socket while you are still
84waiting for data.
85 106
107It is possible to push requests on the read and write queues, and modify
108properties of the stream, even while AnyEvent::Handle is connecting.
109
110When this parameter is specified, then the C<on_prepare>,
111C<on_connect_error> and C<on_connect> callbacks will be called under the
112appropriate circumstances:
113
114=over 4
115
86=item on_error => $cb->($handle) 116=item on_prepare => $cb->($handle)
87 117
118This (rarely used) callback is called before a new connection is
119attempted, but after the file handle has been created (you can access that
120file handle via C<< $handle->{fh} >>). It could be used to prepare the
121file handle with parameters required for the actual connect (as opposed to
122settings that can be changed when the connection is already established).
123
124The return value of this callback should be the connect timeout value in
125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126default timeout is to be used).
127
128=item on_connect => $cb->($handle, $host, $port, $retry->())
129
130This callback is called when a connection has been successfully established.
131
132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
140If, for some reason, the handle is not acceptable, calling C<$retry> will
141continue with the next connection target (in case of multi-homed hosts or
142SRV records there can be multiple connection endpoints). The C<$retry>
143callback can be invoked after the connect callback returns, i.e. one can
144start a handshake and then decide to retry with the next host if the
145handshake fails.
146
147In most cases, you should ignore the C<$retry> parameter.
148
149=item on_connect_error => $cb->($handle, $message)
150
151This callback is called when the connection could not be
152established. C<$!> will contain the relevant error code, and C<$message> a
153message describing it (usually the same as C<"$!">).
154
155If this callback isn't specified, then C<on_error> will be called with a
156fatal error instead.
157
158=back
159
160=item on_error => $cb->($handle, $fatal, $message)
161
88This is the fatal error callback, that is called when, well, a fatal error 162This is the error callback, which is called when, well, some error
89occurs, such as not being able to resolve the hostname, failure to connect 163occured, such as not being able to resolve the hostname, failure to
90or a read error. 164connect, or a read error.
91 165
92The object will not be in a usable state when this callback has been 166Some errors are fatal (which is indicated by C<$fatal> being true). On
93called. 167fatal errors the handle object will be destroyed (by a call to C<< ->
168destroy >>) after invoking the error callback (which means you are free to
169examine the handle object). Examples of fatal errors are an EOF condition
170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
94 173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well.
176
177If you report the error to the user, it is recommended to always output
178the C<$message> argument in human-readable error messages (you don't need
179to report C<"$!"> if you report C<$message>).
180
181If you want to react programmatically to the error, then looking at C<$!>
182and comparing it against some of the documented C<Errno> values is usually
183better than looking at the C<$message>.
184
185Non-fatal errors can be retried by returning, but it is recommended
186to simply ignore this parameter and instead abondon the handle object
187when this callback is invoked. Examples of non-fatal errors are timeouts
188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
189
95On callback entrance, the value of C<$!> contains the operating system 190On entry to the callback, the value of C<$!> contains the operating
96error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>). 191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
97 192C<EPROTO>).
98The callback should throw an exception. If it returns, then
99AnyEvent::Handle will C<croak> for you.
100 193
101While not mandatory, it is I<highly> recommended to set this callback, as 194While not mandatory, it is I<highly> recommended to set this callback, as
102you will not be notified of errors otherwise. The default simply calls 195you will not be notified of errors otherwise. The default just calls
103die. 196C<croak>.
104 197
105=item on_read => $cb->($handle) 198=item on_read => $cb->($handle)
106 199
107This sets the default read callback, which is called when data arrives 200This sets the default read callback, which is called when data arrives
108and no read request is in the queue. 201and no read request is in the queue (unlike read queue callbacks, this
202callback will only be called when at least one octet of data is in the
203read buffer).
109 204
110To access (and remove data from) the read buffer, use the C<< ->rbuf >> 205To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111method or access the C<$handle->{rbuf}> member directly. 206method or access the C<< $handle->{rbuf} >> member directly. Note that you
207must not enlarge or modify the read buffer, you can only remove data at
208the beginning from it.
112 209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
113When an EOF condition is detected then AnyEvent::Handle will first try to 213When an EOF condition is detected, AnyEvent::Handle will first try to
114feed all the remaining data to the queued callbacks and C<on_read> before 214feed all the remaining data to the queued callbacks and C<on_read> before
115calling the C<on_eof> callback. If no progress can be made, then a fatal 215calling the C<on_eof> callback. If no progress can be made, then a fatal
116error will be raised (with C<$!> set to C<EPIPE>). 216error will be raised (with C<$!> set to C<EPIPE>).
117 217
218Note that, unlike requests in the read queue, an C<on_read> callback
219doesn't mean you I<require> some data: if there is an EOF and there
220are outstanding read requests then an error will be flagged. With an
221C<on_read> callback, the C<on_eof> callback will be invoked.
222
223=item on_eof => $cb->($handle)
224
225Set the callback to be called when an end-of-file condition is detected,
226i.e. in the case of a socket, when the other side has closed the
227connection cleanly, and there are no outstanding read requests in the
228queue (if there are read requests, then an EOF counts as an unexpected
229connection close and will be flagged as an error).
230
231For sockets, this just means that the other side has stopped sending data,
232you can still try to write data, and, in fact, one can return from the EOF
233callback and continue writing data, as only the read part has been shut
234down.
235
236If an EOF condition has been detected but no C<on_eof> callback has been
237set, then a fatal error will be raised with C<$!> set to <0>.
238
118=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
119 240
120This sets the callback that is called when the write buffer becomes empty 241This sets the callback that is called once when the write buffer becomes
121(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
122 243
123To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
245
246This callback is useful when you don't want to put all of your write data
247into the queue at once, for example, when you want to write the contents
248of some file to the socket you might not want to read the whole file into
249memory and push it into the queue, but instead only read more data from
250the file when the write queue becomes empty.
251
252=item timeout => $fractional_seconds
253
254=item rtimeout => $fractional_seconds
255
256=item wtimeout => $fractional_seconds
257
258If non-zero, then these enables an "inactivity" timeout: whenever this
259many seconds pass without a successful read or write on the underlying
260file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
261will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
262error will be raised).
263
264There are three variants of the timeouts that work independently of each
265other, for both read and write (triggered when nothing was read I<OR>
266written), just read (triggered when nothing was read), and just write:
267C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
268C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
269C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
270
271Note that timeout processing is active even when you do not have any
272outstanding read or write requests: If you plan to keep the connection
273idle then you should disable the timeout temporarily or ignore the
274timeout in the corresponding C<on_timeout> callback, in which case
275AnyEvent::Handle will simply restart the timeout.
276
277Zero (the default) disables the corresponding timeout.
278
279=item on_timeout => $cb->($handle)
280
281=item on_rtimeout => $cb->($handle)
282
283=item on_wtimeout => $cb->($handle)
284
285Called whenever the inactivity timeout passes. If you return from this
286callback, then the timeout will be reset as if some activity had happened,
287so this condition is not fatal in any way.
124 288
125=item rbuf_max => <bytes> 289=item rbuf_max => <bytes>
126 290
127If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 291If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128when the read buffer ever (strictly) exceeds this size. This is useful to 292when the read buffer ever (strictly) exceeds this size. This is useful to
129avoid denial-of-service attacks. 293avoid some forms of denial-of-service attacks.
130 294
131For example, a server accepting connections from untrusted sources should 295For example, a server accepting connections from untrusted sources should
132be configured to accept only so-and-so much data that it cannot act on 296be configured to accept only so-and-so much data that it cannot act on
133(for example, when expecting a line, an attacker could send an unlimited 297(for example, when expecting a line, an attacker could send an unlimited
134amount of data without a callback ever being called as long as the line 298amount of data without a callback ever being called as long as the line
135isn't finished). 299isn't finished).
136 300
301=item wbuf_max => <bytes>
302
303If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
304when the write buffer ever (strictly) exceeds this size. This is useful to
305avoid some forms of denial-of-service attacks.
306
307Although the units of this parameter is bytes, this is the I<raw> number
308of bytes not yet accepted by the kernel. This can make a difference when
309you e.g. use TLS, as TLS typically makes your write data larger (but it
310can also make it smaller due to compression).
311
312As an example of when this limit is useful, take a chat server that sends
313chat messages to a client. If the client does not read those in a timely
314manner then the send buffer in the server would grow unbounded.
315
316=item autocork => <boolean>
317
318When disabled (the default), C<push_write> will try to immediately
319write the data to the handle if possible. This avoids having to register
320a write watcher and wait for the next event loop iteration, but can
321be inefficient if you write multiple small chunks (on the wire, this
322disadvantage is usually avoided by your kernel's nagle algorithm, see
323C<no_delay>, but this option can save costly syscalls).
324
325When enabled, writes will always be queued till the next event loop
326iteration. This is efficient when you do many small writes per iteration,
327but less efficient when you do a single write only per iteration (or when
328the write buffer often is full). It also increases write latency.
329
330=item no_delay => <boolean>
331
332When doing small writes on sockets, your operating system kernel might
333wait a bit for more data before actually sending it out. This is called
334the Nagle algorithm, and usually it is beneficial.
335
336In some situations you want as low a delay as possible, which can be
337accomplishd by setting this option to a true value.
338
339The default is your operating system's default behaviour (most likely
340enabled). This option explicitly enables or disables it, if possible.
341
342=item keepalive => <boolean>
343
344Enables (default disable) the SO_KEEPALIVE option on the stream socket:
345normally, TCP connections have no time-out once established, so TCP
346connections, once established, can stay alive forever even when the other
347side has long gone. TCP keepalives are a cheap way to take down long-lived
348TCP connections when the other side becomes unreachable. While the default
349is OS-dependent, TCP keepalives usually kick in after around two hours,
350and, if the other side doesn't reply, take down the TCP connection some 10
351to 15 minutes later.
352
353It is harmless to specify this option for file handles that do not support
354keepalives, and enabling it on connections that are potentially long-lived
355is usually a good idea.
356
357=item oobinline => <boolean>
358
359BSD majorly fucked up the implementation of TCP urgent data. The result
360is that almost no OS implements TCP according to the specs, and every OS
361implements it slightly differently.
362
363If you want to handle TCP urgent data, then setting this flag (the default
364is enabled) gives you the most portable way of getting urgent data, by
365putting it into the stream.
366
367Since BSD emulation of OOB data on top of TCP's urgent data can have
368security implications, AnyEvent::Handle sets this flag automatically
369unless explicitly specified. Note that setting this flag after
370establishing a connection I<may> be a bit too late (data loss could
371already have occured on BSD systems), but at least it will protect you
372from most attacks.
373
137=item read_size => <bytes> 374=item read_size => <bytes>
138 375
139The default read block size (the amount of bytes this module will try to read 376The initial read block size, the number of bytes this module will try
140on each [loop iteration). Default: C<4096>. 377to read during each loop iteration. Each handle object will consume
378at least this amount of memory for the read buffer as well, so when
379handling many connections watch out for memory requirements). See also
380C<max_read_size>. Default: C<2048>.
381
382=item max_read_size => <bytes>
383
384The maximum read buffer size used by the dynamic adjustment
385algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
386one go it will double C<read_size> up to the maximum given by this
387option. Default: C<131072> or C<read_size>, whichever is higher.
141 388
142=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
143 390
144Sets the amount of bytes (default: C<0>) that make up an "empty" write 391Sets the number of bytes (default: C<0>) that make up an "empty" write
145buffer: If the write reaches this size or gets even samller it is 392buffer: If the buffer reaches this size or gets even samller it is
146considered empty. 393considered empty.
147 394
395Sometimes it can be beneficial (for performance reasons) to add data to
396the write buffer before it is fully drained, but this is a rare case, as
397the operating system kernel usually buffers data as well, so the default
398is good in almost all cases.
399
400=item linger => <seconds>
401
402If this is non-zero (default: C<3600>), the destructor of the
403AnyEvent::Handle object will check whether there is still outstanding
404write data and will install a watcher that will write this data to the
405socket. No errors will be reported (this mostly matches how the operating
406system treats outstanding data at socket close time).
407
408This will not work for partial TLS data that could not be encoded
409yet. This data will be lost. Calling the C<stoptls> method in time might
410help.
411
412=item peername => $string
413
414A string used to identify the remote site - usually the DNS hostname
415(I<not> IDN!) used to create the connection, rarely the IP address.
416
417Apart from being useful in error messages, this string is also used in TLS
418peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
419verification will be skipped when C<peername> is not specified or is
420C<undef>.
421
148=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149 423
150When this parameter is given, it enables TLS (SSL) mode, that means it 424When this parameter is given, it enables TLS (SSL) mode, that means
151will start making tls handshake and will transparently encrypt/decrypt 425AnyEvent will start a TLS handshake as soon as the connection has been
152data. 426established and will transparently encrypt/decrypt data afterwards.
427
428All TLS protocol errors will be signalled as C<EPROTO>, with an
429appropriate error message.
153 430
154TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
155automatically when you try to create a TLS handle). 432automatically when you try to create a TLS handle): this module doesn't
433have a dependency on that module, so if your module requires it, you have
434to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
435old, you get an C<EPROTO> error.
156 436
157For the TLS server side, use C<accept>, and for the TLS client side of a 437Unlike TCP, TLS has a server and client side: for the TLS server side, use
158connection, use C<connect> mode. 438C<accept>, and for the TLS client side of a connection, use C<connect>
439mode.
159 440
160You can also provide your own TLS connection object, but you have 441You can also provide your own TLS connection object, but you have
161to make sure that you call either C<Net::SSLeay::set_connect_state> 442to make sure that you call either C<Net::SSLeay::set_connect_state>
162or C<Net::SSLeay::set_accept_state> on it before you pass it to 443or C<Net::SSLeay::set_accept_state> on it before you pass it to
163AnyEvent::Handle. 444AnyEvent::Handle. Also, this module will take ownership of this connection
445object.
164 446
447At some future point, AnyEvent::Handle might switch to another TLS
448implementation, then the option to use your own session object will go
449away.
450
451B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
452passing in the wrong integer will lead to certain crash. This most often
453happens when one uses a stylish C<< tls => 1 >> and is surprised about the
454segmentation fault.
455
165See the C<starttls> method if you need to start TLs negotiation later. 456Use the C<< ->starttls >> method if you need to start TLS negotiation later.
166 457
167=item tls_ctx => $ssl_ctx 458=item tls_ctx => $anyevent_tls
168 459
169Use the given Net::SSLeay::CTX object to create the new TLS connection 460Use the given C<AnyEvent::TLS> object to create the new TLS connection
170(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
171missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 462parameter is missing (or C<undef>), then AnyEvent::Handle will use
463C<AnyEvent::Handle::TLS_CTX>.
464
465Instead of an object, you can also specify a hash reference with C<< key
466=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
467new TLS context object.
468
469=item on_starttls => $cb->($handle, $success[, $error_message])
470
471This callback will be invoked when the TLS/SSL handshake has finished. If
472C<$success> is true, then the TLS handshake succeeded, otherwise it failed
473(C<on_stoptls> will not be called in this case).
474
475The session in C<< $handle->{tls} >> can still be examined in this
476callback, even when the handshake was not successful.
477
478TLS handshake failures will not cause C<on_error> to be invoked when this
479callback is in effect, instead, the error message will be passed to C<on_starttls>.
480
481Without this callback, handshake failures lead to C<on_error> being
482called as usual.
483
484Note that you cannot just call C<starttls> again in this callback. If you
485need to do that, start an zero-second timer instead whose callback can
486then call C<< ->starttls >> again.
487
488=item on_stoptls => $cb->($handle)
489
490When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
491set, then it will be invoked after freeing the TLS session. If it is not,
492then a TLS shutdown condition will be treated like a normal EOF condition
493on the handle.
494
495The session in C<< $handle->{tls} >> can still be examined in this
496callback.
497
498This callback will only be called on TLS shutdowns, not when the
499underlying handle signals EOF.
172 500
173=item json => JSON or JSON::XS object 501=item json => JSON or JSON::XS object
174 502
175This is the json coder object used by the C<json> read and write types. 503This is the json coder object used by the C<json> read and write types.
176 504
177If you don't supply it, then AnyEvent::Handle will create and use a 505If you don't supply it, then AnyEvent::Handle will create and use a
178suitable one, which will write and expect UTF-8 encoded JSON texts. 506suitable one (on demand), which will write and expect UTF-8 encoded JSON
507texts.
179 508
180Note that you are responsible to depend on the JSON module if you want to 509Note that you are responsible to depend on the JSON module if you want to
181use this functionality, as AnyEvent does not have a dependency itself. 510use this functionality, as AnyEvent does not have a dependency itself.
182 511
183=item filter_r => $cb
184
185=item filter_w => $cb
186
187These exist, but are undocumented at this time.
188
189=back 512=back
190 513
191=cut 514=cut
192 515
193sub new { 516sub new {
194 my $class = shift; 517 my $class = shift;
195
196 my $self = bless { @_ }, $class; 518 my $self = bless { @_ }, $class;
197 519
198 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 520 if ($self->{fh}) {
521 $self->_start;
522 return unless $self->{fh}; # could be gone by now
523
524 } elsif ($self->{connect}) {
525 require AnyEvent::Socket;
526
527 $self->{peername} = $self->{connect}[0]
528 unless exists $self->{peername};
529
530 $self->{_skip_drain_rbuf} = 1;
531
532 {
533 Scalar::Util::weaken (my $self = $self);
534
535 $self->{_connect} =
536 AnyEvent::Socket::tcp_connect (
537 $self->{connect}[0],
538 $self->{connect}[1],
539 sub {
540 my ($fh, $host, $port, $retry) = @_;
541
542 delete $self->{_connect}; # no longer needed
543
544 if ($fh) {
545 $self->{fh} = $fh;
546
547 delete $self->{_skip_drain_rbuf};
548 $self->_start;
549
550 $self->{on_connect}
551 and $self->{on_connect}($self, $host, $port, sub {
552 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
553 $self->{_skip_drain_rbuf} = 1;
554 &$retry;
555 });
556
557 } else {
558 if ($self->{on_connect_error}) {
559 $self->{on_connect_error}($self, "$!");
560 $self->destroy if $self;
561 } else {
562 $self->_error ($!, 1);
563 }
564 }
565 },
566 sub {
567 local $self->{fh} = $_[0];
568
569 $self->{on_prepare}
570 ? $self->{on_prepare}->($self)
571 : ()
572 }
573 );
574 }
575
576 } else {
577 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
578 }
579
580 $self
581}
582
583sub _start {
584 my ($self) = @_;
585
586 # too many clueless people try to use udp and similar sockets
587 # with AnyEvent::Handle, do them a favour.
588 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
589 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
590 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
199 591
200 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 592 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
201 593
202 if ($self->{tls}) { 594 $self->{_activity} =
203 require Net::SSLeay; 595 $self->{_ractivity} =
596 $self->{_wactivity} = AE::now;
597
598 $self->{read_size} ||= 2048;
599 $self->{max_read_size} = $self->{read_size}
600 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
601
602 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
603 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
604 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
605
606 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
607 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
608
609 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
610
204 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 611 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
205 } 612 if $self->{tls};
206 613
207 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
208 $self->on_error (delete $self->{on_error}) if $self->{on_error};
209 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 614 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
210 $self->on_read (delete $self->{on_read} ) if $self->{on_read};
211 615
212 $self->start_read; 616 $self->start_read
617 if $self->{on_read} || @{ $self->{_queue} };
213 618
214 $self 619 $self->_drain_wbuf;
215} 620}
216 621
217sub _shutdown {
218 my ($self) = @_;
219
220 delete $self->{_rw};
221 delete $self->{_ww};
222 delete $self->{fh};
223}
224
225sub error { 622sub _error {
226 my ($self) = @_; 623 my ($self, $errno, $fatal, $message) = @_;
227 624
228 { 625 $! = $errno;
229 local $!; 626 $message ||= "$!";
230 $self->_shutdown;
231 }
232 627
233 $self->{on_error}($self)
234 if $self->{on_error}; 628 if ($self->{on_error}) {
235 629 $self->{on_error}($self, $fatal, $message);
630 $self->destroy if $fatal;
631 } elsif ($self->{fh} || $self->{connect}) {
632 $self->destroy;
236 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 633 Carp::croak "AnyEvent::Handle uncaught error: $message";
634 }
237} 635}
238 636
239=item $fh = $handle->fh 637=item $fh = $handle->fh
240 638
241This method returns the file handle of the L<AnyEvent::Handle> object. 639This method returns the file handle used to create the L<AnyEvent::Handle> object.
242 640
243=cut 641=cut
244 642
245sub fh { $_[0]{fh} } 643sub fh { $_[0]{fh} }
246 644
262 660
263sub on_eof { 661sub on_eof {
264 $_[0]{on_eof} = $_[1]; 662 $_[0]{on_eof} = $_[1];
265} 663}
266 664
665=item $handle->on_timeout ($cb)
666
667=item $handle->on_rtimeout ($cb)
668
669=item $handle->on_wtimeout ($cb)
670
671Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
672callback, or disables the callback (but not the timeout) if C<$cb> =
673C<undef>. See the C<timeout> constructor argument and method.
674
675=cut
676
677# see below
678
679=item $handle->autocork ($boolean)
680
681Enables or disables the current autocork behaviour (see C<autocork>
682constructor argument). Changes will only take effect on the next write.
683
684=cut
685
686sub autocork {
687 $_[0]{autocork} = $_[1];
688}
689
690=item $handle->no_delay ($boolean)
691
692Enables or disables the C<no_delay> setting (see constructor argument of
693the same name for details).
694
695=cut
696
697sub no_delay {
698 $_[0]{no_delay} = $_[1];
699
700 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
701 if $_[0]{fh};
702}
703
704=item $handle->keepalive ($boolean)
705
706Enables or disables the C<keepalive> setting (see constructor argument of
707the same name for details).
708
709=cut
710
711sub keepalive {
712 $_[0]{keepalive} = $_[1];
713
714 eval {
715 local $SIG{__DIE__};
716 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
717 if $_[0]{fh};
718 };
719}
720
721=item $handle->oobinline ($boolean)
722
723Enables or disables the C<oobinline> setting (see constructor argument of
724the same name for details).
725
726=cut
727
728sub oobinline {
729 $_[0]{oobinline} = $_[1];
730
731 eval {
732 local $SIG{__DIE__};
733 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
734 if $_[0]{fh};
735 };
736}
737
738=item $handle->keepalive ($boolean)
739
740Enables or disables the C<keepalive> setting (see constructor argument of
741the same name for details).
742
743=cut
744
745sub keepalive {
746 $_[0]{keepalive} = $_[1];
747
748 eval {
749 local $SIG{__DIE__};
750 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
751 if $_[0]{fh};
752 };
753}
754
755=item $handle->on_starttls ($cb)
756
757Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
758
759=cut
760
761sub on_starttls {
762 $_[0]{on_starttls} = $_[1];
763}
764
765=item $handle->on_stoptls ($cb)
766
767Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
768
769=cut
770
771sub on_stoptls {
772 $_[0]{on_stoptls} = $_[1];
773}
774
775=item $handle->rbuf_max ($max_octets)
776
777Configures the C<rbuf_max> setting (C<undef> disables it).
778
779=item $handle->wbuf_max ($max_octets)
780
781Configures the C<wbuf_max> setting (C<undef> disables it).
782
783=cut
784
785sub rbuf_max {
786 $_[0]{rbuf_max} = $_[1];
787}
788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
793#############################################################################
794
795=item $handle->timeout ($seconds)
796
797=item $handle->rtimeout ($seconds)
798
799=item $handle->wtimeout ($seconds)
800
801Configures (or disables) the inactivity timeout.
802
803The timeout will be checked instantly, so this method might destroy the
804handle before it returns.
805
806=item $handle->timeout_reset
807
808=item $handle->rtimeout_reset
809
810=item $handle->wtimeout_reset
811
812Reset the activity timeout, as if data was received or sent.
813
814These methods are cheap to call.
815
816=cut
817
818for my $dir ("", "r", "w") {
819 my $timeout = "${dir}timeout";
820 my $tw = "_${dir}tw";
821 my $on_timeout = "on_${dir}timeout";
822 my $activity = "_${dir}activity";
823 my $cb;
824
825 *$on_timeout = sub {
826 $_[0]{$on_timeout} = $_[1];
827 };
828
829 *$timeout = sub {
830 my ($self, $new_value) = @_;
831
832 $new_value >= 0
833 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
834
835 $self->{$timeout} = $new_value;
836 delete $self->{$tw}; &$cb;
837 };
838
839 *{"${dir}timeout_reset"} = sub {
840 $_[0]{$activity} = AE::now;
841 };
842
843 # main workhorse:
844 # reset the timeout watcher, as neccessary
845 # also check for time-outs
846 $cb = sub {
847 my ($self) = @_;
848
849 if ($self->{$timeout} && $self->{fh}) {
850 my $NOW = AE::now;
851
852 # when would the timeout trigger?
853 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
854
855 # now or in the past already?
856 if ($after <= 0) {
857 $self->{$activity} = $NOW;
858
859 if ($self->{$on_timeout}) {
860 $self->{$on_timeout}($self);
861 } else {
862 $self->_error (Errno::ETIMEDOUT);
863 }
864
865 # callback could have changed timeout value, optimise
866 return unless $self->{$timeout};
867
868 # calculate new after
869 $after = $self->{$timeout};
870 }
871
872 Scalar::Util::weaken $self;
873 return unless $self; # ->error could have destroyed $self
874
875 $self->{$tw} ||= AE::timer $after, 0, sub {
876 delete $self->{$tw};
877 $cb->($self);
878 };
879 } else {
880 delete $self->{$tw};
881 }
882 }
883}
884
267############################################################################# 885#############################################################################
268 886
269=back 887=back
270 888
271=head2 WRITE QUEUE 889=head2 WRITE QUEUE
275 893
276The write queue is very simple: you can add data to its end, and 894The write queue is very simple: you can add data to its end, and
277AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
278 896
279When data could be written and the write buffer is shorter then the low 897When data could be written and the write buffer is shorter then the low
280water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
281 899
282=over 4 900=over 4
283 901
284=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
285 903
286Sets the C<on_drain> callback or clears it (see the description of 904Sets the C<on_drain> callback or clears it (see the description of
287C<on_drain> in the constructor). 905C<on_drain> in the constructor).
288 906
907This method may invoke callbacks (and therefore the handle might be
908destroyed after it returns).
909
289=cut 910=cut
290 911
291sub on_drain { 912sub on_drain {
292 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
293 914
294 $self->{on_drain} = $cb; 915 $self->{on_drain} = $cb;
295 916
296 $cb->($self) 917 $cb->($self)
297 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 918 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
298} 919}
299 920
300=item $handle->push_write ($data) 921=item $handle->push_write ($data)
301 922
302Queues the given scalar to be written. You can push as much data as you 923Queues the given scalar to be written. You can push as much data as
303want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
304buffers it independently of the kernel. 925C<AnyEvent::Handle> buffers it independently of the kernel.
926
927This method may invoke callbacks (and therefore the handle might be
928destroyed after it returns).
305 929
306=cut 930=cut
307 931
308sub _drain_wbuf { 932sub _drain_wbuf {
309 my ($self) = @_; 933 my ($self) = @_;
313 Scalar::Util::weaken $self; 937 Scalar::Util::weaken $self;
314 938
315 my $cb = sub { 939 my $cb = sub {
316 my $len = syswrite $self->{fh}, $self->{wbuf}; 940 my $len = syswrite $self->{fh}, $self->{wbuf};
317 941
318 if ($len >= 0) { 942 if (defined $len) {
319 substr $self->{wbuf}, 0, $len, ""; 943 substr $self->{wbuf}, 0, $len, "";
320 944
945 $self->{_activity} = $self->{_wactivity} = AE::now;
946
321 $self->{on_drain}($self) 947 $self->{on_drain}($self)
322 if $self->{low_water_mark} >= length $self->{wbuf} 948 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
323 && $self->{on_drain}; 949 && $self->{on_drain};
324 950
325 delete $self->{_ww} unless length $self->{wbuf}; 951 delete $self->{_ww} unless length $self->{wbuf};
326 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 952 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
327 $self->error; 953 $self->_error ($!, 1);
328 } 954 }
329 }; 955 };
330 956
331 # try to write data immediately 957 # try to write data immediately
332 $cb->(); 958 $cb->() unless $self->{autocork};
333 959
334 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
335 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
336 if length $self->{wbuf}; 962 if length $self->{wbuf};
963
964 if (
965 defined $self->{wbuf_max}
966 && $self->{wbuf_max} < length $self->{wbuf}
967 ) {
968 $self->_error (Errno::ENOSPC, 1), return;
969 }
337 }; 970 };
338} 971}
339 972
340our %WH; 973our %WH;
341 974
975# deprecated
342sub register_write_type($$) { 976sub register_write_type($$) {
343 $WH{$_[0]} = $_[1]; 977 $WH{$_[0]} = $_[1];
344} 978}
345 979
346sub push_write { 980sub push_write {
347 my $self = shift; 981 my $self = shift;
348 982
349 if (@_ > 1) { 983 if (@_ > 1) {
350 my $type = shift; 984 my $type = shift;
351 985
986 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
352 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 987 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
353 ->($self, @_); 988 ->($self, @_);
354 } 989 }
355 990
991 # we downgrade here to avoid hard-to-track-down bugs,
992 # and diagnose the problem earlier and better.
993
356 if ($self->{filter_w}) { 994 if ($self->{tls}) {
357 $self->{filter_w}->($self, \$_[0]); 995 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
996 &_dotls ($self) if $self->{fh};
358 } else { 997 } else {
359 $self->{wbuf} .= $_[0]; 998 utf8::downgrade $self->{wbuf} .= $_[0];
360 $self->_drain_wbuf; 999 $self->_drain_wbuf if $self->{fh};
361 } 1000 }
362} 1001}
363 1002
364=item $handle->push_write (type => @args) 1003=item $handle->push_write (type => @args)
365 1004
366=item $handle->unshift_write (type => @args)
367
368Instead of formatting your data yourself, you can also let this module do 1005Instead of formatting your data yourself, you can also let this module
369the job by specifying a type and type-specific arguments. 1006do the job by specifying a type and type-specific arguments. You
1007can also specify the (fully qualified) name of a package, in which
1008case AnyEvent tries to load the package and then expects to find the
1009C<anyevent_write_type> function inside (see "custom write types", below).
370 1010
371Predefined types are (if you have ideas for additional types, feel free to 1011Predefined types are (if you have ideas for additional types, feel free to
372drop by and tell us): 1012drop by and tell us):
373 1013
374=over 4 1014=over 4
376=item netstring => $string 1016=item netstring => $string
377 1017
378Formats the given value as netstring 1018Formats the given value as netstring
379(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 1019(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
380 1020
381=back
382
383=cut 1021=cut
384 1022
385register_write_type netstring => sub { 1023register_write_type netstring => sub {
386 my ($self, $string) = @_; 1024 my ($self, $string) = @_;
387 1025
388 sprintf "%d:%s,", (length $string), $string 1026 (length $string) . ":$string,"
1027};
1028
1029=item packstring => $format, $data
1030
1031An octet string prefixed with an encoded length. The encoding C<$format>
1032uses the same format as a Perl C<pack> format, but must specify a single
1033integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1034optional C<!>, C<< < >> or C<< > >> modifier).
1035
1036=cut
1037
1038register_write_type packstring => sub {
1039 my ($self, $format, $string) = @_;
1040
1041 pack "$format/a*", $string
389}; 1042};
390 1043
391=item json => $array_or_hashref 1044=item json => $array_or_hashref
392 1045
393Encodes the given hash or array reference into a JSON object. Unless you 1046Encodes the given hash or array reference into a JSON object. Unless you
418Other languages could read single lines terminated by a newline and pass 1071Other languages could read single lines terminated by a newline and pass
419this line into their JSON decoder of choice. 1072this line into their JSON decoder of choice.
420 1073
421=cut 1074=cut
422 1075
1076sub json_coder() {
1077 eval { require JSON::XS; JSON::XS->new->utf8 }
1078 || do { require JSON; JSON->new->utf8 }
1079}
1080
423register_write_type json => sub { 1081register_write_type json => sub {
424 my ($self, $ref) = @_; 1082 my ($self, $ref) = @_;
425 1083
426 require JSON; 1084 my $json = $self->{json} ||= json_coder;
427 1085
428 $self->{json} ? $self->{json}->encode ($ref) 1086 $json->encode ($ref)
429 : JSON::encode_json ($ref)
430}; 1087};
431 1088
432=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1089=item storable => $reference
433 1090
434This function (not method) lets you add your own types to C<push_write>. 1091Freezes the given reference using L<Storable> and writes it to the
1092handle. Uses the C<nfreeze> format.
1093
1094=cut
1095
1096register_write_type storable => sub {
1097 my ($self, $ref) = @_;
1098
1099 require Storable unless $Storable::VERSION;
1100
1101 pack "w/a*", Storable::nfreeze ($ref)
1102};
1103
1104=back
1105
1106=item $handle->push_shutdown
1107
1108Sometimes you know you want to close the socket after writing your data
1109before it was actually written. One way to do that is to replace your
1110C<on_drain> handler by a callback that shuts down the socket (and set
1111C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1112replaces the C<on_drain> callback with:
1113
1114 sub { shutdown $_[0]{fh}, 1 }
1115
1116This simply shuts down the write side and signals an EOF condition to the
1117the peer.
1118
1119You can rely on the normal read queue and C<on_eof> handling
1120afterwards. This is the cleanest way to close a connection.
1121
1122This method may invoke callbacks (and therefore the handle might be
1123destroyed after it returns).
1124
1125=cut
1126
1127sub push_shutdown {
1128 my ($self) = @_;
1129
1130 delete $self->{low_water_mark};
1131 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1132}
1133
1134=item custom write types - Package::anyevent_write_type $handle, @args
1135
1136Instead of one of the predefined types, you can also specify the name of
1137a package. AnyEvent will try to load the package and then expects to find
1138a function named C<anyevent_write_type> inside. If it isn't found, it
1139progressively tries to load the parent package until it either finds the
1140function (good) or runs out of packages (bad).
1141
435Whenever the given C<type> is used, C<push_write> will invoke the code 1142Whenever the given C<type> is used, C<push_write> will the function with
436reference with the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
437 1144
438The code reference is supposed to return a single octet string that will 1145The function is supposed to return a single octet string that will be
439be appended to the write buffer. 1146appended to the write buffer, so you can mentally treat this function as a
1147"arguments to on-the-wire-format" converter.
440 1148
441Note that this is a function, and all types registered this way will be 1149Example: implement a custom write type C<join> that joins the remaining
442global, so try to use unique names. 1150arguments using the first one.
1151
1152 $handle->push_write (My::Type => " ", 1,2,3);
1153
1154 # uses the following package, which can be defined in the "My::Type" or in
1155 # the "My" modules to be auto-loaded, or just about anywhere when the
1156 # My::Type::anyevent_write_type is defined before invoking it.
1157
1158 package My::Type;
1159
1160 sub anyevent_write_type {
1161 my ($handle, $delim, @args) = @_;
1162
1163 join $delim, @args
1164 }
443 1165
444=cut 1166=cut
445 1167
446############################################################################# 1168#############################################################################
447 1169
456ways, the "simple" way, using only C<on_read> and the "complex" way, using 1178ways, the "simple" way, using only C<on_read> and the "complex" way, using
457a queue. 1179a queue.
458 1180
459In the simple case, you just install an C<on_read> callback and whenever 1181In the simple case, you just install an C<on_read> callback and whenever
460new data arrives, it will be called. You can then remove some data (if 1182new data arrives, it will be called. You can then remove some data (if
461enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 1183enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
462or not. 1184leave the data there if you want to accumulate more (e.g. when only a
1185partial message has been received so far), or change the read queue with
1186e.g. C<push_read>.
463 1187
464In the more complex case, you want to queue multiple callbacks. In this 1188In the more complex case, you want to queue multiple callbacks. In this
465case, AnyEvent::Handle will call the first queued callback each time new 1189case, AnyEvent::Handle will call the first queued callback each time new
466data arrives and removes it when it has done its job (see C<push_read>, 1190data arrives (also the first time it is queued) and remove it when it has
467below). 1191done its job (see C<push_read>, below).
468 1192
469This way you can, for example, push three line-reads, followed by reading 1193This way you can, for example, push three line-reads, followed by reading
470a chunk of data, and AnyEvent::Handle will execute them in order. 1194a chunk of data, and AnyEvent::Handle will execute them in order.
471 1195
472Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 1196Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
473the specified number of bytes which give an XML datagram. 1197the specified number of bytes which give an XML datagram.
474 1198
475 # in the default state, expect some header bytes 1199 # in the default state, expect some header bytes
476 $handle->on_read (sub { 1200 $handle->on_read (sub {
477 # some data is here, now queue the length-header-read (4 octets) 1201 # some data is here, now queue the length-header-read (4 octets)
478 shift->unshift_read_chunk (4, sub { 1202 shift->unshift_read (chunk => 4, sub {
479 # header arrived, decode 1203 # header arrived, decode
480 my $len = unpack "N", $_[1]; 1204 my $len = unpack "N", $_[1];
481 1205
482 # now read the payload 1206 # now read the payload
483 shift->unshift_read_chunk ($len, sub { 1207 shift->unshift_read (chunk => $len, sub {
484 my $xml = $_[1]; 1208 my $xml = $_[1];
485 # handle xml 1209 # handle xml
486 }); 1210 });
487 }); 1211 });
488 }); 1212 });
489 1213
490Example 2: Implement a client for a protocol that replies either with 1214Example 2: Implement a client for a protocol that replies either with "OK"
491"OK" and another line or "ERROR" for one request, and 64 bytes for the 1215and another line or "ERROR" for the first request that is sent, and 64
492second request. Due tot he availability of a full queue, we can just 1216bytes for the second request. Due to the availability of a queue, we can
493pipeline sending both requests and manipulate the queue as necessary in 1217just pipeline sending both requests and manipulate the queue as necessary
494the callbacks: 1218in the callbacks.
495 1219
496 # request one 1220When the first callback is called and sees an "OK" response, it will
1221C<unshift> another line-read. This line-read will be queued I<before> the
122264-byte chunk callback.
1223
1224 # request one, returns either "OK + extra line" or "ERROR"
497 $handle->push_write ("request 1\015\012"); 1225 $handle->push_write ("request 1\015\012");
498 1226
499 # we expect "ERROR" or "OK" as response, so push a line read 1227 # we expect "ERROR" or "OK" as response, so push a line read
500 $handle->push_read_line (sub { 1228 $handle->push_read (line => sub {
501 # if we got an "OK", we have to _prepend_ another line, 1229 # if we got an "OK", we have to _prepend_ another line,
502 # so it will be read before the second request reads its 64 bytes 1230 # so it will be read before the second request reads its 64 bytes
503 # which are already in the queue when this callback is called 1231 # which are already in the queue when this callback is called
504 # we don't do this in case we got an error 1232 # we don't do this in case we got an error
505 if ($_[1] eq "OK") { 1233 if ($_[1] eq "OK") {
506 $_[0]->unshift_read_line (sub { 1234 $_[0]->unshift_read (line => sub {
507 my $response = $_[1]; 1235 my $response = $_[1];
508 ... 1236 ...
509 }); 1237 });
510 } 1238 }
511 }); 1239 });
512 1240
513 # request two 1241 # request two, simply returns 64 octets
514 $handle->push_write ("request 2\015\012"); 1242 $handle->push_write ("request 2\015\012");
515 1243
516 # simply read 64 bytes, always 1244 # simply read 64 bytes, always
517 $handle->push_read_chunk (64, sub { 1245 $handle->push_read (chunk => 64, sub {
518 my $response = $_[1]; 1246 my $response = $_[1];
519 ... 1247 ...
520 }); 1248 });
521 1249
522=over 4 1250=over 4
523 1251
524=cut 1252=cut
525 1253
526sub _drain_rbuf { 1254sub _drain_rbuf {
527 my ($self) = @_; 1255 my ($self) = @_;
1256
1257 # avoid recursion
1258 return if $self->{_skip_drain_rbuf};
1259 local $self->{_skip_drain_rbuf} = 1;
1260
1261 while () {
1262 # we need to use a separate tls read buffer, as we must not receive data while
1263 # we are draining the buffer, and this can only happen with TLS.
1264 $self->{rbuf} .= delete $self->{_tls_rbuf}
1265 if exists $self->{_tls_rbuf};
1266
1267 my $len = length $self->{rbuf};
1268
1269 if (my $cb = shift @{ $self->{_queue} }) {
1270 unless ($cb->($self)) {
1271 # no progress can be made
1272 # (not enough data and no data forthcoming)
1273 $self->_error (Errno::EPIPE, 1), return
1274 if $self->{_eof};
1275
1276 unshift @{ $self->{_queue} }, $cb;
1277 last;
1278 }
1279 } elsif ($self->{on_read}) {
1280 last unless $len;
1281
1282 $self->{on_read}($self);
1283
1284 if (
1285 $len == length $self->{rbuf} # if no data has been consumed
1286 && !@{ $self->{_queue} } # and the queue is still empty
1287 && $self->{on_read} # but we still have on_read
1288 ) {
1289 # no further data will arrive
1290 # so no progress can be made
1291 $self->_error (Errno::EPIPE, 1), return
1292 if $self->{_eof};
1293
1294 last; # more data might arrive
1295 }
1296 } else {
1297 # read side becomes idle
1298 delete $self->{_rw} unless $self->{tls};
1299 last;
1300 }
1301 }
1302
1303 if ($self->{_eof}) {
1304 $self->{on_eof}
1305 ? $self->{on_eof}($self)
1306 : $self->_error (0, 1, "Unexpected end-of-file");
1307
1308 return;
1309 }
528 1310
529 if ( 1311 if (
530 defined $self->{rbuf_max} 1312 defined $self->{rbuf_max}
531 && $self->{rbuf_max} < length $self->{rbuf} 1313 && $self->{rbuf_max} < length $self->{rbuf}
532 ) { 1314 ) {
533 $! = &Errno::ENOSPC; 1315 $self->_error (Errno::ENOSPC, 1), return;
534 $self->error;
535 } 1316 }
536 1317
537 return if $self->{in_drain}; 1318 # may need to restart read watcher
538 local $self->{in_drain} = 1; 1319 unless ($self->{_rw}) {
539 1320 $self->start_read
540 while (my $len = length $self->{rbuf}) { 1321 if $self->{on_read} || @{ $self->{_queue} };
541 no strict 'refs';
542 if (my $cb = shift @{ $self->{_queue} }) {
543 unless ($cb->($self)) {
544 if ($self->{_eof}) {
545 # no progress can be made (not enough data and no data forthcoming)
546 $! = &Errno::EPIPE;
547 $self->error;
548 }
549
550 unshift @{ $self->{_queue} }, $cb;
551 return;
552 }
553 } elsif ($self->{on_read}) {
554 $self->{on_read}($self);
555
556 if (
557 $self->{_eof} # if no further data will arrive
558 && $len == length $self->{rbuf} # and no data has been consumed
559 && !@{ $self->{_queue} } # and the queue is still empty
560 && $self->{on_read} # and we still want to read data
561 ) {
562 # then no progress can be made
563 $! = &Errno::EPIPE;
564 $self->error;
565 }
566 } else {
567 # read side becomes idle
568 delete $self->{_rw};
569 return;
570 }
571 }
572
573 if ($self->{_eof}) {
574 $self->_shutdown;
575 $self->{on_eof}($self)
576 if $self->{on_eof};
577 } 1322 }
578} 1323}
579 1324
580=item $handle->on_read ($cb) 1325=item $handle->on_read ($cb)
581 1326
582This replaces the currently set C<on_read> callback, or clears it (when 1327This replaces the currently set C<on_read> callback, or clears it (when
583the new callback is C<undef>). See the description of C<on_read> in the 1328the new callback is C<undef>). See the description of C<on_read> in the
584constructor. 1329constructor.
585 1330
1331This method may invoke callbacks (and therefore the handle might be
1332destroyed after it returns).
1333
586=cut 1334=cut
587 1335
588sub on_read { 1336sub on_read {
589 my ($self, $cb) = @_; 1337 my ($self, $cb) = @_;
590 1338
591 $self->{on_read} = $cb; 1339 $self->{on_read} = $cb;
1340 $self->_drain_rbuf if $cb;
592} 1341}
593 1342
594=item $handle->rbuf 1343=item $handle->rbuf
595 1344
596Returns the read buffer (as a modifiable lvalue). 1345Returns the read buffer (as a modifiable lvalue). You can also access the
1346read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1347much faster, and no less clean).
597 1348
598You can access the read buffer directly as the C<< ->{rbuf} >> member, if 1349The only operation allowed on the read buffer (apart from looking at it)
599you want. 1350is removing data from its beginning. Otherwise modifying or appending to
1351it is not allowed and will lead to hard-to-track-down bugs.
600 1352
601NOTE: The read buffer should only be used or modified if the C<on_read>, 1353NOTE: The read buffer should only be used or modified in the C<on_read>
602C<push_read> or C<unshift_read> methods are used. The other read methods 1354callback or when C<push_read> or C<unshift_read> are used with a single
603automatically manage the read buffer. 1355callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1356will manage the read buffer on their own.
604 1357
605=cut 1358=cut
606 1359
607sub rbuf : lvalue { 1360sub rbuf : lvalue {
608 $_[0]{rbuf} 1361 $_[0]{rbuf}
625 1378
626If enough data was available, then the callback must remove all data it is 1379If enough data was available, then the callback must remove all data it is
627interested in (which can be none at all) and return a true value. After returning 1380interested in (which can be none at all) and return a true value. After returning
628true, it will be removed from the queue. 1381true, it will be removed from the queue.
629 1382
1383These methods may invoke callbacks (and therefore the handle might be
1384destroyed after it returns).
1385
630=cut 1386=cut
631 1387
632our %RH; 1388our %RH;
633 1389
634sub register_read_type($$) { 1390sub register_read_type($$) {
640 my $cb = pop; 1396 my $cb = pop;
641 1397
642 if (@_) { 1398 if (@_) {
643 my $type = shift; 1399 my $type = shift;
644 1400
1401 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
645 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1402 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
646 ->($self, $cb, @_); 1403 ->($self, $cb, @_);
647 } 1404 }
648 1405
649 push @{ $self->{_queue} }, $cb; 1406 push @{ $self->{_queue} }, $cb;
650 $self->_drain_rbuf; 1407 $self->_drain_rbuf;
655 my $cb = pop; 1412 my $cb = pop;
656 1413
657 if (@_) { 1414 if (@_) {
658 my $type = shift; 1415 my $type = shift;
659 1416
1417 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
660 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1418 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
661 ->($self, $cb, @_); 1419 ->($self, $cb, @_);
662 } 1420 }
663
664 1421
665 unshift @{ $self->{_queue} }, $cb; 1422 unshift @{ $self->{_queue} }, $cb;
666 $self->_drain_rbuf; 1423 $self->_drain_rbuf;
667} 1424}
668 1425
670 1427
671=item $handle->unshift_read (type => @args, $cb) 1428=item $handle->unshift_read (type => @args, $cb)
672 1429
673Instead of providing a callback that parses the data itself you can chose 1430Instead of providing a callback that parses the data itself you can chose
674between a number of predefined parsing formats, for chunks of data, lines 1431between a number of predefined parsing formats, for chunks of data, lines
675etc. 1432etc. You can also specify the (fully qualified) name of a package, in
1433which case AnyEvent tries to load the package and then expects to find the
1434C<anyevent_read_type> function inside (see "custom read types", below).
676 1435
677Predefined types are (if you have ideas for additional types, feel free to 1436Predefined types are (if you have ideas for additional types, feel free to
678drop by and tell us): 1437drop by and tell us):
679 1438
680=over 4 1439=over 4
686data. 1445data.
687 1446
688Example: read 2 bytes. 1447Example: read 2 bytes.
689 1448
690 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
691 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
692 }); 1451 });
693 1452
694=cut 1453=cut
695 1454
696register_read_type chunk => sub { 1455register_read_type chunk => sub {
701 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 1460 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
702 1 1461 1
703 } 1462 }
704}; 1463};
705 1464
706# compatibility with older API
707sub push_read_chunk {
708 $_[0]->push_read (chunk => $_[1], $_[2]);
709}
710
711sub unshift_read_chunk {
712 $_[0]->unshift_read (chunk => $_[1], $_[2]);
713}
714
715=item line => [$eol, ]$cb->($handle, $line, $eol) 1465=item line => [$eol, ]$cb->($handle, $line, $eol)
716 1466
717The callback will be called only once a full line (including the end of 1467The callback will be called only once a full line (including the end of
718line marker, C<$eol>) has been read. This line (excluding the end of line 1468line marker, C<$eol>) has been read. This line (excluding the end of line
719marker) will be passed to the callback as second argument (C<$line>), and 1469marker) will be passed to the callback as second argument (C<$line>), and
734=cut 1484=cut
735 1485
736register_read_type line => sub { 1486register_read_type line => sub {
737 my ($self, $cb, $eol) = @_; 1487 my ($self, $cb, $eol) = @_;
738 1488
739 $eol = qr|(\015?\012)| if @_ < 3; 1489 if (@_ < 3) {
740 $eol = quotemeta $eol unless ref $eol; 1490 # this is faster then the generic code below
741 $eol = qr|^(.*?)($eol)|s;
742
743 sub { 1491 sub {
744 $_[0]{rbuf} =~ s/$eol// or return; 1492 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1493 or return;
745 1494
1495 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
746 $cb->($_[0], $1, $2); 1496 $cb->($_[0], $str, "$1");
747 1
748 }
749};
750
751# compatibility with older API
752sub push_read_line {
753 my $self = shift;
754 $self->push_read (line => @_);
755}
756
757sub unshift_read_line {
758 my $self = shift;
759 $self->unshift_read (line => @_);
760}
761
762=item netstring => $cb->($handle, $string)
763
764A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
765
766Throws an error with C<$!> set to EBADMSG on format violations.
767
768=cut
769
770register_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 } 1497 1
779 return;
780 } 1498 }
1499 } else {
1500 $eol = quotemeta $eol unless ref $eol;
1501 $eol = qr|^(.*?)($eol)|s;
781 1502
782 my $len = $1; 1503 sub {
1504 $_[0]{rbuf} =~ s/$eol// or return;
783 1505
784 $self->unshift_read (chunk => $len, sub { 1506 $cb->($_[0], "$1", "$2");
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 }); 1507 1
794 }); 1508 }
795
796 1
797 } 1509 }
798}; 1510};
799 1511
800=item regex => $accept[, $reject[, $skip], $cb->($handle, $data) 1512=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
801 1513
821the receive buffer when neither C<$accept> nor C<$reject> match, 1533the receive buffer when neither C<$accept> nor C<$reject> match,
822and everything preceding and including the match will be accepted 1534and everything preceding and including the match will be accepted
823unconditionally. This is useful to skip large amounts of data that you 1535unconditionally. This is useful to skip large amounts of data that you
824know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1536know cannot be matched, so that the C<$accept> or C<$reject> regex do not
825have to start matching from the beginning. This is purely an optimisation 1537have to start matching from the beginning. This is purely an optimisation
826and is usually worth only when you expect more than a few kilobytes. 1538and is usually worth it only when you expect more than a few kilobytes.
827 1539
828Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1540Example: expect a http header, which ends at C<\015\012\015\012>. Since we
829expect the header to be very large (it isn't in practise, but...), we use 1541expect the header to be very large (it isn't in practice, but...), we use
830a skip regex to skip initial portions. The skip regex is tricky in that 1542a skip regex to skip initial portions. The skip regex is tricky in that
831it only accepts something not ending in either \015 or \012, as these are 1543it only accepts something not ending in either \015 or \012, as these are
832required for the accept regex. 1544required for the accept regex.
833 1545
834 $handle->push_read (regex => 1546 $handle->push_read (regex =>
847 1559
848 sub { 1560 sub {
849 # accept 1561 # accept
850 if ($$rbuf =~ $accept) { 1562 if ($$rbuf =~ $accept) {
851 $data .= substr $$rbuf, 0, $+[0], ""; 1563 $data .= substr $$rbuf, 0, $+[0], "";
852 $cb->($self, $data); 1564 $cb->($_[0], $data);
853 return 1; 1565 return 1;
854 } 1566 }
855 1567
856 # reject 1568 # reject
857 if ($reject && $$rbuf =~ $reject) { 1569 if ($reject && $$rbuf =~ $reject) {
858 $! = &Errno::EBADMSG; 1570 $_[0]->_error (Errno::EBADMSG);
859 $self->error;
860 } 1571 }
861 1572
862 # skip 1573 # skip
863 if ($skip && $$rbuf =~ $skip) { 1574 if ($skip && $$rbuf =~ $skip) {
864 $data .= substr $$rbuf, 0, $+[0], ""; 1575 $data .= substr $$rbuf, 0, $+[0], "";
866 1577
867 () 1578 ()
868 } 1579 }
869}; 1580};
870 1581
1582=item netstring => $cb->($handle, $string)
1583
1584A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1585
1586Throws an error with C<$!> set to EBADMSG on format violations.
1587
1588=cut
1589
1590register_read_type netstring => sub {
1591 my ($self, $cb) = @_;
1592
1593 sub {
1594 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1595 if ($_[0]{rbuf} =~ /[^0-9]/) {
1596 $_[0]->_error (Errno::EBADMSG);
1597 }
1598 return;
1599 }
1600
1601 my $len = $1;
1602
1603 $_[0]->unshift_read (chunk => $len, sub {
1604 my $string = $_[1];
1605 $_[0]->unshift_read (chunk => 1, sub {
1606 if ($_[1] eq ",") {
1607 $cb->($_[0], $string);
1608 } else {
1609 $_[0]->_error (Errno::EBADMSG);
1610 }
1611 });
1612 });
1613
1614 1
1615 }
1616};
1617
1618=item packstring => $format, $cb->($handle, $string)
1619
1620An octet string prefixed with an encoded length. The encoding C<$format>
1621uses the same format as a Perl C<pack> format, but must specify a single
1622integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1623optional C<!>, C<< < >> or C<< > >> modifier).
1624
1625For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1626EPP uses a prefix of C<N> (4 octtes).
1627
1628Example: read a block of data prefixed by its length in BER-encoded
1629format (very efficient).
1630
1631 $handle->push_read (packstring => "w", sub {
1632 my ($handle, $data) = @_;
1633 });
1634
1635=cut
1636
1637register_read_type packstring => sub {
1638 my ($self, $cb, $format) = @_;
1639
1640 sub {
1641 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1642 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1643 or return;
1644
1645 $format = length pack $format, $len;
1646
1647 # bypass unshift if we already have the remaining chunk
1648 if ($format + $len <= length $_[0]{rbuf}) {
1649 my $data = substr $_[0]{rbuf}, $format, $len;
1650 substr $_[0]{rbuf}, 0, $format + $len, "";
1651 $cb->($_[0], $data);
1652 } else {
1653 # remove prefix
1654 substr $_[0]{rbuf}, 0, $format, "";
1655
1656 # read remaining chunk
1657 $_[0]->unshift_read (chunk => $len, $cb);
1658 }
1659
1660 1
1661 }
1662};
1663
871=item json => $cb->($handle, $hash_or_arrayref) 1664=item json => $cb->($handle, $hash_or_arrayref)
872 1665
873Reads a JSON object or array, decodes it and passes it to the callback. 1666Reads a JSON object or array, decodes it and passes it to the
1667callback. When a parse error occurs, an C<EBADMSG> error will be raised.
874 1668
875If a C<json> object was passed to the constructor, then that will be used 1669If a C<json> object was passed to the constructor, then that will be used
876for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1670for the final decode, otherwise it will create a JSON coder expecting UTF-8.
877 1671
878This read type uses the incremental parser available with JSON version 1672This read type uses the incremental parser available with JSON version
885the C<json> write type description, above, for an actual example. 1679the C<json> write type description, above, for an actual example.
886 1680
887=cut 1681=cut
888 1682
889register_read_type json => sub { 1683register_read_type json => sub {
890 my ($self, $cb, $accept, $reject, $skip) = @_; 1684 my ($self, $cb) = @_;
891 1685
892 require JSON; 1686 my $json = $self->{json} ||= json_coder;
893 1687
894 my $data; 1688 my $data;
895 my $rbuf = \$self->{rbuf}; 1689 my $rbuf = \$self->{rbuf};
896 1690
897 my $json = $self->{json} ||= JSON->new->utf8;
898
899 sub { 1691 sub {
900 my $ref = $json->incr_parse ($self->{rbuf}); 1692 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
901 1693
902 if ($ref) { 1694 if ($ref) {
903 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
904 $json->incr_text = ""; 1696 $json->incr_text = "";
905 $cb->($self, $ref); 1697 $cb->($_[0], $ref);
906 1698
907 1 1699 1
1700 } elsif ($@) {
1701 # error case
1702 $json->incr_skip;
1703
1704 $_[0]{rbuf} = $json->incr_text;
1705 $json->incr_text = "";
1706
1707 $_[0]->_error (Errno::EBADMSG);
1708
1709 ()
908 } else { 1710 } else {
909 $self->{rbuf} = ""; 1711 $_[0]{rbuf} = "";
1712
910 () 1713 ()
911 } 1714 }
912 } 1715 }
913}; 1716};
914 1717
1718=item storable => $cb->($handle, $ref)
1719
1720Deserialises a L<Storable> frozen representation as written by the
1721C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1722data).
1723
1724Raises C<EBADMSG> error if the data could not be decoded.
1725
1726=cut
1727
1728register_read_type storable => sub {
1729 my ($self, $cb) = @_;
1730
1731 require Storable unless $Storable::VERSION;
1732
1733 sub {
1734 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1735 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1736 or return;
1737
1738 my $format = length pack "w", $len;
1739
1740 # bypass unshift if we already have the remaining chunk
1741 if ($format + $len <= length $_[0]{rbuf}) {
1742 my $data = substr $_[0]{rbuf}, $format, $len;
1743 substr $_[0]{rbuf}, 0, $format + $len, "";
1744
1745 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1746 or return $_[0]->_error (Errno::EBADMSG);
1747 } else {
1748 # remove prefix
1749 substr $_[0]{rbuf}, 0, $format, "";
1750
1751 # read remaining chunk
1752 $_[0]->unshift_read (chunk => $len, sub {
1753 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1754 or $_[0]->_error (Errno::EBADMSG);
1755 });
1756 }
1757
1758 1
1759 }
1760};
1761
1762=item tls_detect => $cb->($handle, $detect, $major, $minor)
1763
1764Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1765record without consuming anything. Only SSL version 3 or higher
1766is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1767SSL2-compatible framing is supported).
1768
1769If it detects that the input data is likely TLS, it calls the callback
1770with a true value for C<$detect> and the (on-wire) TLS version as second
1771and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
17723.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1773be definitely not TLS, it calls the callback with a false value for
1774C<$detect>.
1775
1776The callback could use this information to decide whether or not to start
1777TLS negotiation.
1778
1779In all cases the data read so far is passed to the following read
1780handlers.
1781
1782Usually you want to use the C<tls_autostart> read type instead.
1783
1784If you want to design a protocol that works in the presence of TLS
1785dtection, make sure that any non-TLS data doesn't start with the octet 22
1786(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1787read type does are a bit more strict, but might losen in the future to
1788accomodate protocol changes.
1789
1790This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1791L<Net::SSLeay>).
1792
1793=item tls_autostart => $tls[, $tls_ctx]
1794
1795Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1796to start tls by calling C<starttls> with the given arguments.
1797
1798In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1799been configured to accept, as servers do not normally send a handshake on
1800their own and ths cannot be detected in this way.
1801
1802See C<tls_detect> above for more details.
1803
1804Example: give the client a chance to start TLS before accepting a text
1805line.
1806
1807 $hdl->push_read (tls_detect => "accept");
1808 $hdl->push_read (line => sub {
1809 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1810 });
1811
1812=cut
1813
1814register_read_type tls_detect => sub {
1815 my ($self, $cb) = @_;
1816
1817 sub {
1818 # this regex matches a full or partial tls record
1819 if (
1820 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1821 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1822 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1823 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1824 ) {
1825 return if 3 != length $1; # partial match, can't decide yet
1826
1827 # full match, valid TLS record
1828 my ($major, $minor) = unpack "CC", $1;
1829 $cb->($self, "accept", $major + $minor * 0.1);
1830 } else {
1831 # mismatch == guaranteed not TLS
1832 $cb->($self, undef);
1833 }
1834
1835 1
1836 }
1837};
1838
1839register_read_type tls_autostart => sub {
1840 my ($self, @tls) = @_;
1841
1842 $RH{tls_detect}($self, sub {
1843 return unless $_[1];
1844 $_[0]->starttls (@tls);
1845 })
1846};
1847
915=back 1848=back
916 1849
917=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1850=item custom read types - Package::anyevent_read_type $handle, $cb, @args
918 1851
919This function (not method) lets you add your own types to C<push_read>. 1852Instead of one of the predefined types, you can also specify the name
1853of a package. AnyEvent will try to load the package and then expects to
1854find a function named C<anyevent_read_type> inside. If it isn't found, it
1855progressively tries to load the parent package until it either finds the
1856function (good) or runs out of packages (bad).
920 1857
921Whenever the given C<type> is used, C<push_read> will invoke the code 1858Whenever this type is used, C<push_read> will invoke the function with the
922reference with the handle object, the callback and the remaining 1859handle object, the original callback and the remaining arguments.
923arguments.
924 1860
925The code reference is supposed to return a callback (usually a closure) 1861The function is supposed to return a callback (usually a closure) that
926that works as a plain read callback (see C<< ->push_read ($cb) >>). 1862works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1863mentally treat the function as a "configurable read type to read callback"
1864converter.
927 1865
928It should invoke the passed callback when it is done reading (remember to 1866It should invoke the original callback when it is done reading (remember
929pass C<$handle> as first argument as all other callbacks do that). 1867to pass C<$handle> as first argument as all other callbacks do that,
1868although there is no strict requirement on this).
930 1869
931Note that this is a function, and all types registered this way will be
932global, so try to use unique names.
933
934For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1870For examples, see the source of this module (F<perldoc -m
935search for C<register_read_type>)). 1871AnyEvent::Handle>, search for C<register_read_type>)).
936 1872
937=item $handle->stop_read 1873=item $handle->stop_read
938 1874
939=item $handle->start_read 1875=item $handle->start_read
940 1876
941In rare cases you actually do not want to read anything from the 1877In rare cases you actually do not want to read anything from the
942socket. In this case you can call C<stop_read>. Neither C<on_read> no 1878socket. In this case you can call C<stop_read>. Neither C<on_read> nor
943any queued callbacks will be executed then. To start reading again, call 1879any queued callbacks will be executed then. To start reading again, call
944C<start_read>. 1880C<start_read>.
945 1881
1882Note that AnyEvent::Handle will automatically C<start_read> for you when
1883you change the C<on_read> callback or push/unshift a read callback, and it
1884will automatically C<stop_read> for you when neither C<on_read> is set nor
1885there are any read requests in the queue.
1886
1887In older versions of this module (<= 5.3), these methods had no effect,
1888as TLS does not support half-duplex connections. In current versions they
1889work as expected, as this behaviour is required to avoid certain resource
1890attacks, where the program would be forced to read (and buffer) arbitrary
1891amounts of data before being able to send some data. The drawback is that
1892some readings of the the SSL/TLS specifications basically require this
1893attack to be working, as SSL/TLS implementations might stall sending data
1894during a rehandshake.
1895
1896As a guideline, during the initial handshake, you should not stop reading,
1897and as a client, it might cause problems, depending on your application.
1898
946=cut 1899=cut
947 1900
948sub stop_read { 1901sub stop_read {
949 my ($self) = @_; 1902 my ($self) = @_;
950 1903
952} 1905}
953 1906
954sub start_read { 1907sub start_read {
955 my ($self) = @_; 1908 my ($self) = @_;
956 1909
957 unless ($self->{_rw} || $self->{_eof}) { 1910 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
958 Scalar::Util::weaken $self; 1911 Scalar::Util::weaken $self;
959 1912
960 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1913 $self->{_rw} = AE::io $self->{fh}, 0, sub {
961 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1914 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
962 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1915 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
963 1916
964 if ($len > 0) { 1917 if ($len > 0) {
965 $self->{filter_r} 1918 $self->{_activity} = $self->{_ractivity} = AE::now;
966 ? $self->{filter_r}->($self, $rbuf) 1919
1920 if ($self->{tls}) {
1921 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1922
1923 &_dotls ($self);
1924 } else {
967 : $self->_drain_rbuf; 1925 $self->_drain_rbuf;
1926 }
1927
1928 if ($len == $self->{read_size}) {
1929 $self->{read_size} *= 2;
1930 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1931 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1932 }
968 1933
969 } elsif (defined $len) { 1934 } elsif (defined $len) {
970 delete $self->{_rw}; 1935 delete $self->{_rw};
971 $self->{_eof} = 1; 1936 $self->{_eof} = 1;
972 $self->_drain_rbuf; 1937 $self->_drain_rbuf;
973 1938
974 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1939 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
975 return $self->error; 1940 return $self->_error ($!, 1);
976 } 1941 }
977 }); 1942 };
978 } 1943 }
979} 1944}
980 1945
1946our $ERROR_SYSCALL;
1947our $ERROR_WANT_READ;
1948
1949sub _tls_error {
1950 my ($self, $err) = @_;
1951
1952 return $self->_error ($!, 1)
1953 if $err == Net::SSLeay::ERROR_SYSCALL ();
1954
1955 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1956
1957 # reduce error string to look less scary
1958 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1959
1960 if ($self->{_on_starttls}) {
1961 (delete $self->{_on_starttls})->($self, undef, $err);
1962 &_freetls;
1963 } else {
1964 &_freetls;
1965 $self->_error (Errno::EPROTO, 1, $err);
1966 }
1967}
1968
1969# poll the write BIO and send the data if applicable
1970# also decode read data if possible
1971# this is basiclaly our TLS state machine
1972# more efficient implementations are possible with openssl,
1973# but not with the buggy and incomplete Net::SSLeay.
981sub _dotls { 1974sub _dotls {
982 my ($self) = @_; 1975 my ($self) = @_;
983 1976
1977 my $tmp;
1978
984 if (length $self->{_tls_wbuf}) { 1979 if (length $self->{_tls_wbuf}) {
985 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1980 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
986 substr $self->{_tls_wbuf}, 0, $len, ""; 1981 substr $self->{_tls_wbuf}, 0, $tmp, "";
987 } 1982 }
988 }
989 1983
1984 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1985 return $self->_tls_error ($tmp)
1986 if $tmp != $ERROR_WANT_READ
1987 && ($tmp != $ERROR_SYSCALL || $!);
1988 }
1989
1990 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1991 unless (length $tmp) {
1992 $self->{_on_starttls}
1993 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1994 &_freetls;
1995
1996 if ($self->{on_stoptls}) {
1997 $self->{on_stoptls}($self);
1998 return;
1999 } else {
2000 # let's treat SSL-eof as we treat normal EOF
2001 delete $self->{_rw};
2002 $self->{_eof} = 1;
2003 }
2004 }
2005
2006 $self->{_tls_rbuf} .= $tmp;
2007 $self->_drain_rbuf;
2008 $self->{tls} or return; # tls session might have gone away in callback
2009 }
2010
2011 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
2012 return $self->_tls_error ($tmp)
2013 if $tmp != $ERROR_WANT_READ
2014 && ($tmp != $ERROR_SYSCALL || $!);
2015
990 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2016 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
991 $self->{wbuf} .= $buf; 2017 $self->{wbuf} .= $tmp;
992 $self->_drain_wbuf; 2018 $self->_drain_wbuf;
2019 $self->{tls} or return; # tls session might have gone away in callback
993 } 2020 }
994 2021
995 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) { 2022 $self->{_on_starttls}
996 $self->{rbuf} .= $buf; 2023 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
997 $self->_drain_rbuf; 2024 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
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} 2025}
1013 2026
1014=item $handle->starttls ($tls[, $tls_ctx]) 2027=item $handle->starttls ($tls[, $tls_ctx])
1015 2028
1016Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2029Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1017object is created, you can also do that at a later time by calling 2030object is created, you can also do that at a later time by calling
1018C<starttls>. 2031C<starttls>. See the C<tls> constructor argument for general info.
2032
2033Starting TLS is currently an asynchronous operation - when you push some
2034write data and then call C<< ->starttls >> then TLS negotiation will start
2035immediately, after which the queued write data is then sent. This might
2036change in future versions, so best make sure you have no outstanding write
2037data when calling this method.
1019 2038
1020The first argument is the same as the C<tls> constructor argument (either 2039The first argument is the same as the C<tls> constructor argument (either
1021C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2040C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1022 2041
1023The second argument is the optional C<Net::SSLeay::CTX> object that is 2042The second argument is the optional C<AnyEvent::TLS> object that is used
1024used when AnyEvent::Handle has to create its own TLS connection object. 2043when AnyEvent::Handle has to create its own TLS connection object, or
2044a hash reference with C<< key => value >> pairs that will be used to
2045construct a new context.
1025 2046
1026The TLS connection object will end up in C<< $handle->{tls} >> after this 2047The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1027call and can be used or changed to your liking. Note that the handshake 2048context in C<< $handle->{tls_ctx} >> after this call and can be used or
1028might have already started when this function returns. 2049changed to your liking. Note that the handshake might have already started
2050when this function returns.
1029 2051
1030=cut 2052Due to bugs in OpenSSL, it might or might not be possible to do multiple
2053handshakes on the same stream. It is best to not attempt to use the
2054stream after stopping TLS.
1031 2055
1032# TODO: maybe document... 2056This method may invoke callbacks (and therefore the handle might be
2057destroyed after it returns).
2058
2059=cut
2060
2061our %TLS_CACHE; #TODO not yet documented, should we?
2062
1033sub starttls { 2063sub starttls {
1034 my ($self, $ssl, $ctx) = @_; 2064 my ($self, $tls, $ctx) = @_;
1035 2065
1036 $self->stoptls; 2066 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
2067 if $self->{tls};
1037 2068
1038 if ($ssl eq "accept") { 2069 unless (defined $AnyEvent::TLS::VERSION) {
1039 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 2070 eval {
1040 Net::SSLeay::set_accept_state ($ssl); 2071 require Net::SSLeay;
1041 } elsif ($ssl eq "connect") { 2072 require AnyEvent::TLS;
1042 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 2073 1
1043 Net::SSLeay::set_connect_state ($ssl); 2074 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2075 }
2076
2077 $self->{tls} = $tls;
2078 $self->{tls_ctx} = $ctx if @_ > 2;
2079
2080 return unless $self->{fh};
2081
2082 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
2083 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
2084
2085 $tls = delete $self->{tls};
2086 $ctx = $self->{tls_ctx};
2087
2088 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
2089
2090 if ("HASH" eq ref $ctx) {
2091 if ($ctx->{cache}) {
2092 my $key = $ctx+0;
2093 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
2094 } else {
2095 $ctx = new AnyEvent::TLS %$ctx;
2096 }
2097 }
1044 } 2098
1045 2099 $self->{tls_ctx} = $ctx || TLS_CTX ();
1046 $self->{tls} = $ssl; 2100 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1047 2101
1048 # basically, this is deep magic (because SSL_read should have the same issues) 2102 # basically, this is deep magic (because SSL_read should have the same issues)
1049 # but the openssl maintainers basically said: "trust us, it just works". 2103 # but the openssl maintainers basically said: "trust us, it just works".
1050 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2104 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1051 # and mismaintained ssleay-module doesn't even offer them). 2105 # and mismaintained ssleay-module doesn't even offer them).
1052 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 2106 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
2107 #
2108 # in short: this is a mess.
2109 #
2110 # note that we do not try to keep the length constant between writes as we are required to do.
2111 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
2112 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
2113 # have identity issues in that area.
1053 Net::SSLeay::CTX_set_mode ($self->{tls}, 2114# Net::SSLeay::CTX_set_mode ($ssl,
1054 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2115# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1055 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2116# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
2117 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1056 2118
1057 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2119 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1058 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2120 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1059 2121
2122 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2123 $self->{rbuf} = "";
2124
1060 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2125 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1061 2126
1062 $self->{filter_w} = sub { 2127 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1063 $_[0]{_tls_wbuf} .= ${$_[1]}; 2128 if $self->{on_starttls};
1064 &_dotls; 2129
1065 }; 2130 &_dotls; # need to trigger the initial handshake
1066 $self->{filter_r} = sub { 2131 $self->start_read; # make sure we actually do read
1067 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1068 &_dotls;
1069 };
1070} 2132}
1071 2133
1072=item $handle->stoptls 2134=item $handle->stoptls
1073 2135
1074Destroys the SSL connection, if any. Partial read or write data will be 2136Shuts down the SSL connection - this makes a proper EOF handshake by
1075lost. 2137sending a close notify to the other side, but since OpenSSL doesn't
2138support non-blocking shut downs, it is not guaranteed that you can re-use
2139the stream afterwards.
2140
2141This method may invoke callbacks (and therefore the handle might be
2142destroyed after it returns).
1076 2143
1077=cut 2144=cut
1078 2145
1079sub stoptls { 2146sub stoptls {
1080 my ($self) = @_; 2147 my ($self) = @_;
1081 2148
1082 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 2149 if ($self->{tls} && $self->{fh}) {
2150 Net::SSLeay::shutdown ($self->{tls});
1083 2151
1084 delete $self->{_rbio}; 2152 &_dotls;
1085 delete $self->{_wbio}; 2153
1086 delete $self->{_tls_wbuf}; 2154# # we don't give a shit. no, we do, but we can't. no...#d#
1087 delete $self->{filter_r}; 2155# # we, we... have to use openssl :/#d#
1088 delete $self->{filter_w}; 2156# &_freetls;#d#
2157 }
1089} 2158}
2159
2160sub _freetls {
2161 my ($self) = @_;
2162
2163 return unless $self->{tls};
2164
2165 $self->{tls_ctx}->_put_session (delete $self->{tls})
2166 if $self->{tls} > 0;
2167
2168 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2169}
2170
2171=item $handle->resettls
2172
2173This rarely-used method simply resets and TLS state on the handle, usually
2174causing data loss.
2175
2176One case where it may be useful is when you want to skip over the data in
2177the stream but you are not interested in interpreting it, so data loss is
2178no concern.
2179
2180=cut
2181
2182*resettls = \&_freetls;
1090 2183
1091sub DESTROY { 2184sub DESTROY {
1092 my $self = shift; 2185 my ($self) = @_;
1093 2186
1094 $self->stoptls; 2187 &_freetls;
2188
2189 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
2190
2191 if ($linger && length $self->{wbuf} && $self->{fh}) {
2192 my $fh = delete $self->{fh};
2193 my $wbuf = delete $self->{wbuf};
2194
2195 my @linger;
2196
2197 push @linger, AE::io $fh, 1, sub {
2198 my $len = syswrite $fh, $wbuf, length $wbuf;
2199
2200 if ($len > 0) {
2201 substr $wbuf, 0, $len, "";
2202 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
2203 @linger = (); # end
2204 }
2205 };
2206 push @linger, AE::timer $linger, 0, sub {
2207 @linger = ();
2208 };
2209 }
1095} 2210}
2211
2212=item $handle->destroy
2213
2214Shuts down the handle object as much as possible - this call ensures that
2215no further callbacks will be invoked and as many resources as possible
2216will be freed. Any method you will call on the handle object after
2217destroying it in this way will be silently ignored (and it will return the
2218empty list).
2219
2220Normally, you can just "forget" any references to an AnyEvent::Handle
2221object and it will simply shut down. This works in fatal error and EOF
2222callbacks, as well as code outside. It does I<NOT> work in a read or write
2223callback, so when you want to destroy the AnyEvent::Handle object from
2224within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
2225that case.
2226
2227Destroying the handle object in this way has the advantage that callbacks
2228will be removed as well, so if those are the only reference holders (as
2229is common), then one doesn't need to do anything special to break any
2230reference cycles.
2231
2232The handle might still linger in the background and write out remaining
2233data, as specified by the C<linger> option, however.
2234
2235=cut
2236
2237sub destroy {
2238 my ($self) = @_;
2239
2240 $self->DESTROY;
2241 %$self = ();
2242 bless $self, "AnyEvent::Handle::destroyed";
2243}
2244
2245sub AnyEvent::Handle::destroyed::AUTOLOAD {
2246 #nop
2247}
2248
2249=item $handle->destroyed
2250
2251Returns false as long as the handle hasn't been destroyed by a call to C<<
2252->destroy >>, true otherwise.
2253
2254Can be useful to decide whether the handle is still valid after some
2255callback possibly destroyed the handle. For example, C<< ->push_write >>,
2256C<< ->starttls >> and other methods can call user callbacks, which in turn
2257can destroy the handle, so work can be avoided by checking sometimes:
2258
2259 $hdl->starttls ("accept");
2260 return if $hdl->destroyed;
2261 $hdl->push_write (...
2262
2263Note that the call to C<push_write> will silently be ignored if the handle
2264has been destroyed, so often you can just ignore the possibility of the
2265handle being destroyed.
2266
2267=cut
2268
2269sub destroyed { 0 }
2270sub AnyEvent::Handle::destroyed::destroyed { 1 }
1096 2271
1097=item AnyEvent::Handle::TLS_CTX 2272=item AnyEvent::Handle::TLS_CTX
1098 2273
1099This function creates and returns the Net::SSLeay::CTX object used by 2274This function creates and returns the AnyEvent::TLS object used by default
1100default for TLS mode. 2275for TLS mode.
1101 2276
1102The context is created like this: 2277The context is created by calling L<AnyEvent::TLS> without any arguments.
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 2278
1112=cut 2279=cut
1113 2280
1114our $TLS_CTX; 2281our $TLS_CTX;
1115 2282
1116sub TLS_CTX() { 2283sub TLS_CTX() {
1117 $TLS_CTX || do { 2284 $TLS_CTX ||= do {
1118 require Net::SSLeay; 2285 require AnyEvent::TLS;
1119 2286
1120 Net::SSLeay::load_error_strings (); 2287 new AnyEvent::TLS
1121 Net::SSLeay::SSLeay_add_ssl_algorithms (); 2288 }
1122 Net::SSLeay::randomize (); 2289}
1123 2290
1124 $TLS_CTX = Net::SSLeay::CTX_new (); 2291=back
1125 2292
1126 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1127 2293
1128 $TLS_CTX 2294=head1 NONFREQUENTLY ASKED QUESTIONS
2295
2296=over 4
2297
2298=item I C<undef> the AnyEvent::Handle reference inside my callback and
2299still get further invocations!
2300
2301That's because AnyEvent::Handle keeps a reference to itself when handling
2302read or write callbacks.
2303
2304It is only safe to "forget" the reference inside EOF or error callbacks,
2305from within all other callbacks, you need to explicitly call the C<<
2306->destroy >> method.
2307
2308=item Why is my C<on_eof> callback never called?
2309
2310Probably because your C<on_error> callback is being called instead: When
2311you have outstanding requests in your read queue, then an EOF is
2312considered an error as you clearly expected some data.
2313
2314To avoid this, make sure you have an empty read queue whenever your handle
2315is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2316an C<on_read> handler that simply pushes the first read requests in the
2317queue.
2318
2319See also the next question, which explains this in a bit more detail.
2320
2321=item How can I serve requests in a loop?
2322
2323Most protocols consist of some setup phase (authentication for example)
2324followed by a request handling phase, where the server waits for requests
2325and handles them, in a loop.
2326
2327There are two important variants: The first (traditional, better) variant
2328handles requests until the server gets some QUIT command, causing it to
2329close the connection first (highly desirable for a busy TCP server). A
2330client dropping the connection is an error, which means this variant can
2331detect an unexpected detection close.
2332
2333To handle this case, always make sure you have a non-empty read queue, by
2334pushing the "read request start" handler on it:
2335
2336 # we assume a request starts with a single line
2337 my @start_request; @start_request = (line => sub {
2338 my ($hdl, $line) = @_;
2339
2340 ... handle request
2341
2342 # push next request read, possibly from a nested callback
2343 $hdl->push_read (@start_request);
2344 });
2345
2346 # auth done, now go into request handling loop
2347 # now push the first @start_request
2348 $hdl->push_read (@start_request);
2349
2350By always having an outstanding C<push_read>, the handle always expects
2351some data and raises the C<EPIPE> error when the connction is dropped
2352unexpectedly.
2353
2354The second variant is a protocol where the client can drop the connection
2355at any time. For TCP, this means that the server machine may run out of
2356sockets easier, and in general, it means you cannot distinguish a protocl
2357failure/client crash from a normal connection close. Nevertheless, these
2358kinds of protocols are common (and sometimes even the best solution to the
2359problem).
2360
2361Having an outstanding read request at all times is possible if you ignore
2362C<EPIPE> errors, but this doesn't help with when the client drops the
2363connection during a request, which would still be an error.
2364
2365A better solution is to push the initial request read in an C<on_read>
2366callback. This avoids an error, as when the server doesn't expect data
2367(i.e. is idly waiting for the next request, an EOF will not raise an
2368error, but simply result in an C<on_eof> callback. It is also a bit slower
2369and simpler:
2370
2371 # auth done, now go into request handling loop
2372 $hdl->on_read (sub {
2373 my ($hdl) = @_;
2374
2375 # called each time we receive data but the read queue is empty
2376 # simply start read the request
2377
2378 $hdl->push_read (line => sub {
2379 my ($hdl, $line) = @_;
2380
2381 ... handle request
2382
2383 # do nothing special when the request has been handled, just
2384 # let the request queue go empty.
2385 });
2386 });
2387
2388=item I get different callback invocations in TLS mode/Why can't I pause
2389reading?
2390
2391Unlike, say, TCP, TLS connections do not consist of two independent
2392communication channels, one for each direction. Or put differently, the
2393read and write directions are not independent of each other: you cannot
2394write data unless you are also prepared to read, and vice versa.
2395
2396This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2397callback invocations when you are not expecting any read data - the reason
2398is that AnyEvent::Handle always reads in TLS mode.
2399
2400During the connection, you have to make sure that you always have a
2401non-empty read-queue, or an C<on_read> watcher. At the end of the
2402connection (or when you no longer want to use it) you can call the
2403C<destroy> method.
2404
2405=item How do I read data until the other side closes the connection?
2406
2407If you just want to read your data into a perl scalar, the easiest way
2408to achieve this is by setting an C<on_read> callback that does nothing,
2409clearing the C<on_eof> callback and in the C<on_error> callback, the data
2410will be in C<$_[0]{rbuf}>:
2411
2412 $handle->on_read (sub { });
2413 $handle->on_eof (undef);
2414 $handle->on_error (sub {
2415 my $data = delete $_[0]{rbuf};
2416 });
2417
2418Note that this example removes the C<rbuf> member from the handle object,
2419which is not normally allowed by the API. It is expressly permitted in
2420this case only, as the handle object needs to be destroyed afterwards.
2421
2422The reason to use C<on_error> is that TCP connections, due to latencies
2423and packets loss, might get closed quite violently with an error, when in
2424fact all data has been received.
2425
2426It is usually better to use acknowledgements when transferring data,
2427to make sure the other side hasn't just died and you got the data
2428intact. This is also one reason why so many internet protocols have an
2429explicit QUIT command.
2430
2431=item I don't want to destroy the handle too early - how do I wait until
2432all data has been written?
2433
2434After writing your last bits of data, set the C<on_drain> callback
2435and destroy the handle in there - with the default setting of
2436C<low_water_mark> this will be called precisely when all data has been
2437written to the socket:
2438
2439 $handle->push_write (...);
2440 $handle->on_drain (sub {
2441 AE::log debug => "All data submitted to the kernel.";
2442 undef $handle;
2443 });
2444
2445If you just want to queue some data and then signal EOF to the other side,
2446consider using C<< ->push_shutdown >> instead.
2447
2448=item I want to contact a TLS/SSL server, I don't care about security.
2449
2450If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2451connect to it and then create the AnyEvent::Handle with the C<tls>
2452parameter:
2453
2454 tcp_connect $host, $port, sub {
2455 my ($fh) = @_;
2456
2457 my $handle = new AnyEvent::Handle
2458 fh => $fh,
2459 tls => "connect",
2460 on_error => sub { ... };
2461
2462 $handle->push_write (...);
1129 } 2463 };
1130} 2464
2465=item I want to contact a TLS/SSL server, I do care about security.
2466
2467Then you should additionally enable certificate verification, including
2468peername verification, if the protocol you use supports it (see
2469L<AnyEvent::TLS>, C<verify_peername>).
2470
2471E.g. for HTTPS:
2472
2473 tcp_connect $host, $port, sub {
2474 my ($fh) = @_;
2475
2476 my $handle = new AnyEvent::Handle
2477 fh => $fh,
2478 peername => $host,
2479 tls => "connect",
2480 tls_ctx => { verify => 1, verify_peername => "https" },
2481 ...
2482
2483Note that you must specify the hostname you connected to (or whatever
2484"peername" the protocol needs) as the C<peername> argument, otherwise no
2485peername verification will be done.
2486
2487The above will use the system-dependent default set of trusted CA
2488certificates. If you want to check against a specific CA, add the
2489C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
2490
2491 tls_ctx => {
2492 verify => 1,
2493 verify_peername => "https",
2494 ca_file => "my-ca-cert.pem",
2495 },
2496
2497=item I want to create a TLS/SSL server, how do I do that?
2498
2499Well, you first need to get a server certificate and key. You have
2500three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
2501self-signed certificate (cheap. check the search engine of your choice,
2502there are many tutorials on the net) or c) make your own CA (tinyca2 is a
2503nice program for that purpose).
2504
2505Then create a file with your private key (in PEM format, see
2506L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
2507file should then look like this:
2508
2509 -----BEGIN RSA PRIVATE KEY-----
2510 ...header data
2511 ... lots of base64'y-stuff
2512 -----END RSA PRIVATE KEY-----
2513
2514 -----BEGIN CERTIFICATE-----
2515 ... lots of base64'y-stuff
2516 -----END CERTIFICATE-----
2517
2518The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
2519specify this file as C<cert_file>:
2520
2521 tcp_server undef, $port, sub {
2522 my ($fh) = @_;
2523
2524 my $handle = new AnyEvent::Handle
2525 fh => $fh,
2526 tls => "accept",
2527 tls_ctx => { cert_file => "my-server-keycert.pem" },
2528 ...
2529
2530When you have intermediate CA certificates that your clients might not
2531know about, just append them to the C<cert_file>.
1131 2532
1132=back 2533=back
1133 2534
1134=head1 SUBCLASSING AnyEvent::Handle 2535=head1 SUBCLASSING AnyEvent::Handle
1135 2536
1141=over 4 2542=over 4
1142 2543
1143=item * all constructor arguments become object members. 2544=item * all constructor arguments become object members.
1144 2545
1145At least initially, when you pass a C<tls>-argument to the constructor it 2546At least initially, when you pass a C<tls>-argument to the constructor it
1146will end up in C<< $handle->{tls} >>. Those members might be changes or 2547will end up in C<< $handle->{tls} >>. Those members might be changed or
1147mutated later on (for example C<tls> will hold the TLS connection object). 2548mutated later on (for example C<tls> will hold the TLS connection object).
1148 2549
1149=item * other object member names are prefixed with an C<_>. 2550=item * other object member names are prefixed with an C<_>.
1150 2551
1151All object members not explicitly documented (internal use) are prefixed 2552All object members not explicitly documented (internal use) are prefixed
1154 2555
1155=item * all members not documented here and not prefixed with an underscore 2556=item * all members not documented here and not prefixed with an underscore
1156are free to use in subclasses. 2557are free to use in subclasses.
1157 2558
1158Of course, new versions of AnyEvent::Handle may introduce more "public" 2559Of course, new versions of AnyEvent::Handle may introduce more "public"
1159member variables, but thats just life, at least it is documented. 2560member variables, but that's just life. At least it is documented.
1160 2561
1161=back 2562=back
1162 2563
1163=head1 AUTHOR 2564=head1 AUTHOR
1164 2565
1165Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2566Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1166 2567
1167=cut 2568=cut
1168 2569
11691; # End of AnyEvent::Handle 25701
2571

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