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Revision 1.41 by root, Tue May 27 05:47:36 2008 UTC vs.
Revision 1.241 by root, Fri Sep 5 22:17:26 2014 UTC

1package AnyEvent::Handle;
2
3no warnings;
4use strict;
5
6use AnyEvent ();
7use AnyEvent::Util qw(WSAWOULDBLOCK);
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>.
172 464
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.
500
173=item json => JSON or JSON::XS object 501=item json => L<JSON>, L<JSON::PP> or L<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
507JSON texts (either using L<JSON::XS> or L<JSON>). The written texts are
508guaranteed not to contain any newline character.
179 509
510For security reasons, this encoder will likely I<not> handle numbers and
511strings, only arrays and objects/hashes. The reason is that originally
512JSON was self-delimited, but Dougles Crockford thought it was a splendid
513idea to redefine JSON incompatibly, so this is no longer true.
514
515For protocols that used back-to-back JSON texts, this might lead to
516run-ins, where two or more JSON texts will be interpreted as one JSON
517text.
518
519For this reason, if the default encoder uses L<JSON::XS>, it will default
520to not allowing anything but arrays and objects/hashes, at least for the
521forseeable future (it will change at some point). This might or might not
522be true for the L<JSON> module, so this might cause a security issue.
523
524If you depend on either behaviour, you should create your own json object
525and pass it in explicitly.
526
527=item cbor => L<CBOR::XS> object
528
529This is the cbor coder object used by the C<cbor> read and write types.
530
531If you don't supply it, then AnyEvent::Handle will create and use a
532suitable one (on demand), which will write CBOR without using extensions,
533if possible.
534
180Note that you are responsible to depend on the JSON module if you want to 535Note that you are responsible to depend on the L<CBOR::XS> module if you
181use this functionality, as AnyEvent does not have a dependency itself. 536want to use this functionality, as AnyEvent does not have a dependency on
182 537it itself.
183=item filter_r => $cb
184
185=item filter_w => $cb
186
187These exist, but are undocumented at this time.
188 538
189=back 539=back
190 540
191=cut 541=cut
192 542
193sub new { 543sub new {
194 my $class = shift; 544 my $class = shift;
195
196 my $self = bless { @_ }, $class; 545 my $self = bless { @_ }, $class;
197 546
198 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 547 if ($self->{fh}) {
548 $self->_start;
549 return unless $self->{fh}; # could be gone by now
550
551 } elsif ($self->{connect}) {
552 require AnyEvent::Socket;
553
554 $self->{peername} = $self->{connect}[0]
555 unless exists $self->{peername};
556
557 $self->{_skip_drain_rbuf} = 1;
558
559 {
560 Scalar::Util::weaken (my $self = $self);
561
562 $self->{_connect} =
563 AnyEvent::Socket::tcp_connect (
564 $self->{connect}[0],
565 $self->{connect}[1],
566 sub {
567 my ($fh, $host, $port, $retry) = @_;
568
569 delete $self->{_connect}; # no longer needed
570
571 if ($fh) {
572 $self->{fh} = $fh;
573
574 delete $self->{_skip_drain_rbuf};
575 $self->_start;
576
577 $self->{on_connect}
578 and $self->{on_connect}($self, $host, $port, sub {
579 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
580 $self->{_skip_drain_rbuf} = 1;
581 &$retry;
582 });
583
584 } else {
585 if ($self->{on_connect_error}) {
586 $self->{on_connect_error}($self, "$!");
587 $self->destroy if $self;
588 } else {
589 $self->_error ($!, 1);
590 }
591 }
592 },
593 sub {
594 local $self->{fh} = $_[0];
595
596 $self->{on_prepare}
597 ? $self->{on_prepare}->($self)
598 : ()
599 }
600 );
601 }
602
603 } else {
604 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
605 }
606
607 $self
608}
609
610sub _start {
611 my ($self) = @_;
612
613 # too many clueless people try to use udp and similar sockets
614 # with AnyEvent::Handle, do them a favour.
615 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
616 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
617 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
199 618
200 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 619 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
201 620
202 if ($self->{tls}) { 621 $self->{_activity} =
203 require Net::SSLeay; 622 $self->{_ractivity} =
623 $self->{_wactivity} = AE::now;
624
625 $self->{read_size} ||= 2048;
626 $self->{max_read_size} = $self->{read_size}
627 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
628
629 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
630 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
631 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
632
633 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
634 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
635
636 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
637
204 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 638 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
205 } 639 if $self->{tls};
206 640
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}; 641 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
210 $self->on_read (delete $self->{on_read} ) if $self->{on_read};
211 642
212 $self->start_read; 643 $self->start_read
644 if $self->{on_read} || @{ $self->{_queue} };
213 645
214 $self 646 $self->_drain_wbuf;
215} 647}
216 648
217sub _shutdown {
218 my ($self) = @_;
219
220 delete $self->{_rw};
221 delete $self->{_ww};
222 delete $self->{fh};
223}
224
225sub error { 649sub _error {
226 my ($self) = @_; 650 my ($self, $errno, $fatal, $message) = @_;
227 651
228 { 652 $! = $errno;
229 local $!; 653 $message ||= "$!";
230 $self->_shutdown;
231 }
232 654
233 $self->{on_error}($self)
234 if $self->{on_error}; 655 if ($self->{on_error}) {
235 656 $self->{on_error}($self, $fatal, $message);
657 $self->destroy if $fatal;
658 } elsif ($self->{fh} || $self->{connect}) {
659 $self->destroy;
236 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 660 Carp::croak "AnyEvent::Handle uncaught error: $message";
661 }
237} 662}
238 663
239=item $fh = $handle->fh 664=item $fh = $handle->fh
240 665
241This method returns the file handle of the L<AnyEvent::Handle> object. 666This method returns the file handle used to create the L<AnyEvent::Handle> object.
242 667
243=cut 668=cut
244 669
245sub fh { $_[0]{fh} } 670sub fh { $_[0]{fh} }
246 671
262 687
263sub on_eof { 688sub on_eof {
264 $_[0]{on_eof} = $_[1]; 689 $_[0]{on_eof} = $_[1];
265} 690}
266 691
692=item $handle->on_timeout ($cb)
693
694=item $handle->on_rtimeout ($cb)
695
696=item $handle->on_wtimeout ($cb)
697
698Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
699callback, or disables the callback (but not the timeout) if C<$cb> =
700C<undef>. See the C<timeout> constructor argument and method.
701
702=cut
703
704# see below
705
706=item $handle->autocork ($boolean)
707
708Enables or disables the current autocork behaviour (see C<autocork>
709constructor argument). Changes will only take effect on the next write.
710
711=cut
712
713sub autocork {
714 $_[0]{autocork} = $_[1];
715}
716
717=item $handle->no_delay ($boolean)
718
719Enables or disables the C<no_delay> setting (see constructor argument of
720the same name for details).
721
722=cut
723
724sub no_delay {
725 $_[0]{no_delay} = $_[1];
726
727 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
728 if $_[0]{fh};
729}
730
731=item $handle->keepalive ($boolean)
732
733Enables or disables the C<keepalive> setting (see constructor argument of
734the same name for details).
735
736=cut
737
738sub keepalive {
739 $_[0]{keepalive} = $_[1];
740
741 eval {
742 local $SIG{__DIE__};
743 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
744 if $_[0]{fh};
745 };
746}
747
748=item $handle->oobinline ($boolean)
749
750Enables or disables the C<oobinline> setting (see constructor argument of
751the same name for details).
752
753=cut
754
755sub oobinline {
756 $_[0]{oobinline} = $_[1];
757
758 eval {
759 local $SIG{__DIE__};
760 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
761 if $_[0]{fh};
762 };
763}
764
765=item $handle->keepalive ($boolean)
766
767Enables or disables the C<keepalive> setting (see constructor argument of
768the same name for details).
769
770=cut
771
772sub keepalive {
773 $_[0]{keepalive} = $_[1];
774
775 eval {
776 local $SIG{__DIE__};
777 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
778 if $_[0]{fh};
779 };
780}
781
782=item $handle->on_starttls ($cb)
783
784Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
785
786=cut
787
788sub on_starttls {
789 $_[0]{on_starttls} = $_[1];
790}
791
792=item $handle->on_stoptls ($cb)
793
794Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
795
796=cut
797
798sub on_stoptls {
799 $_[0]{on_stoptls} = $_[1];
800}
801
802=item $handle->rbuf_max ($max_octets)
803
804Configures the C<rbuf_max> setting (C<undef> disables it).
805
806=item $handle->wbuf_max ($max_octets)
807
808Configures the C<wbuf_max> setting (C<undef> disables it).
809
810=cut
811
812sub rbuf_max {
813 $_[0]{rbuf_max} = $_[1];
814}
815
816sub wbuf_max {
817 $_[0]{wbuf_max} = $_[1];
818}
819
820#############################################################################
821
822=item $handle->timeout ($seconds)
823
824=item $handle->rtimeout ($seconds)
825
826=item $handle->wtimeout ($seconds)
827
828Configures (or disables) the inactivity timeout.
829
830The timeout will be checked instantly, so this method might destroy the
831handle before it returns.
832
833=item $handle->timeout_reset
834
835=item $handle->rtimeout_reset
836
837=item $handle->wtimeout_reset
838
839Reset the activity timeout, as if data was received or sent.
840
841These methods are cheap to call.
842
843=cut
844
845for my $dir ("", "r", "w") {
846 my $timeout = "${dir}timeout";
847 my $tw = "_${dir}tw";
848 my $on_timeout = "on_${dir}timeout";
849 my $activity = "_${dir}activity";
850 my $cb;
851
852 *$on_timeout = sub {
853 $_[0]{$on_timeout} = $_[1];
854 };
855
856 *$timeout = sub {
857 my ($self, $new_value) = @_;
858
859 $new_value >= 0
860 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
861
862 $self->{$timeout} = $new_value;
863 delete $self->{$tw}; &$cb;
864 };
865
866 *{"${dir}timeout_reset"} = sub {
867 $_[0]{$activity} = AE::now;
868 };
869
870 # main workhorse:
871 # reset the timeout watcher, as neccessary
872 # also check for time-outs
873 $cb = sub {
874 my ($self) = @_;
875
876 if ($self->{$timeout} && $self->{fh}) {
877 my $NOW = AE::now;
878
879 # when would the timeout trigger?
880 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
881
882 # now or in the past already?
883 if ($after <= 0) {
884 $self->{$activity} = $NOW;
885
886 if ($self->{$on_timeout}) {
887 $self->{$on_timeout}($self);
888 } else {
889 $self->_error (Errno::ETIMEDOUT);
890 }
891
892 # callback could have changed timeout value, optimise
893 return unless $self->{$timeout};
894
895 # calculate new after
896 $after = $self->{$timeout};
897 }
898
899 Scalar::Util::weaken $self;
900 return unless $self; # ->error could have destroyed $self
901
902 $self->{$tw} ||= AE::timer $after, 0, sub {
903 delete $self->{$tw};
904 $cb->($self);
905 };
906 } else {
907 delete $self->{$tw};
908 }
909 }
910}
911
267############################################################################# 912#############################################################################
268 913
269=back 914=back
270 915
271=head2 WRITE QUEUE 916=head2 WRITE QUEUE
275 920
276The write queue is very simple: you can add data to its end, and 921The 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. 922AnyEvent::Handle will automatically try to get rid of it for you.
278 923
279When data could be written and the write buffer is shorter then the low 924When data could be written and the write buffer is shorter then the low
280water mark, the C<on_drain> callback will be invoked. 925water mark, the C<on_drain> callback will be invoked once.
281 926
282=over 4 927=over 4
283 928
284=item $handle->on_drain ($cb) 929=item $handle->on_drain ($cb)
285 930
286Sets the C<on_drain> callback or clears it (see the description of 931Sets the C<on_drain> callback or clears it (see the description of
287C<on_drain> in the constructor). 932C<on_drain> in the constructor).
288 933
934This method may invoke callbacks (and therefore the handle might be
935destroyed after it returns).
936
289=cut 937=cut
290 938
291sub on_drain { 939sub on_drain {
292 my ($self, $cb) = @_; 940 my ($self, $cb) = @_;
293 941
294 $self->{on_drain} = $cb; 942 $self->{on_drain} = $cb;
295 943
296 $cb->($self) 944 $cb->($self)
297 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 945 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
298} 946}
299 947
300=item $handle->push_write ($data) 948=item $handle->push_write ($data)
301 949
302Queues the given scalar to be written. You can push as much data as you 950Queues the given scalar to be written. You can push as much data as
303want (only limited by the available memory), as C<AnyEvent::Handle> 951you want (only limited by the available memory and C<wbuf_max>), as
304buffers it independently of the kernel. 952C<AnyEvent::Handle> buffers it independently of the kernel.
953
954This method may invoke callbacks (and therefore the handle might be
955destroyed after it returns).
305 956
306=cut 957=cut
307 958
308sub _drain_wbuf { 959sub _drain_wbuf {
309 my ($self) = @_; 960 my ($self) = @_;
313 Scalar::Util::weaken $self; 964 Scalar::Util::weaken $self;
314 965
315 my $cb = sub { 966 my $cb = sub {
316 my $len = syswrite $self->{fh}, $self->{wbuf}; 967 my $len = syswrite $self->{fh}, $self->{wbuf};
317 968
318 if ($len >= 0) { 969 if (defined $len) {
319 substr $self->{wbuf}, 0, $len, ""; 970 substr $self->{wbuf}, 0, $len, "";
320 971
972 $self->{_activity} = $self->{_wactivity} = AE::now;
973
321 $self->{on_drain}($self) 974 $self->{on_drain}($self)
322 if $self->{low_water_mark} >= length $self->{wbuf} 975 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
323 && $self->{on_drain}; 976 && $self->{on_drain};
324 977
325 delete $self->{_ww} unless length $self->{wbuf}; 978 delete $self->{_ww} unless length $self->{wbuf};
326 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) { 979 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
327 $self->error; 980 $self->_error ($!, 1);
328 } 981 }
329 }; 982 };
330 983
331 # try to write data immediately 984 # try to write data immediately
332 $cb->(); 985 $cb->() unless $self->{autocork};
333 986
334 # if still data left in wbuf, we need to poll 987 # if still data left in wbuf, we need to poll
335 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 988 $self->{_ww} = AE::io $self->{fh}, 1, $cb
336 if length $self->{wbuf}; 989 if length $self->{wbuf};
990
991 if (
992 defined $self->{wbuf_max}
993 && $self->{wbuf_max} < length $self->{wbuf}
994 ) {
995 $self->_error (Errno::ENOSPC, 1), return;
996 }
337 }; 997 };
338} 998}
339 999
340our %WH; 1000our %WH;
341 1001
1002# deprecated
342sub register_write_type($$) { 1003sub register_write_type($$) {
343 $WH{$_[0]} = $_[1]; 1004 $WH{$_[0]} = $_[1];
344} 1005}
345 1006
346sub push_write { 1007sub push_write {
347 my $self = shift; 1008 my $self = shift;
348 1009
349 if (@_ > 1) { 1010 if (@_ > 1) {
350 my $type = shift; 1011 my $type = shift;
351 1012
1013 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
352 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 1014 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
353 ->($self, @_); 1015 ->($self, @_);
354 } 1016 }
355 1017
1018 # we downgrade here to avoid hard-to-track-down bugs,
1019 # and diagnose the problem earlier and better.
1020
356 if ($self->{filter_w}) { 1021 if ($self->{tls}) {
357 $self->{filter_w}->($self, \$_[0]); 1022 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
1023 &_dotls ($self) if $self->{fh};
358 } else { 1024 } else {
359 $self->{wbuf} .= $_[0]; 1025 utf8::downgrade $self->{wbuf} .= $_[0];
360 $self->_drain_wbuf; 1026 $self->_drain_wbuf if $self->{fh};
361 } 1027 }
362} 1028}
363 1029
364=item $handle->push_write (type => @args) 1030=item $handle->push_write (type => @args)
365 1031
366=item $handle->unshift_write (type => @args)
367
368Instead of formatting your data yourself, you can also let this module do 1032Instead of formatting your data yourself, you can also let this module
369the job by specifying a type and type-specific arguments. 1033do the job by specifying a type and type-specific arguments. You
1034can also specify the (fully qualified) name of a package, in which
1035case AnyEvent tries to load the package and then expects to find the
1036C<anyevent_write_type> function inside (see "custom write types", below).
370 1037
371Predefined types are (if you have ideas for additional types, feel free to 1038Predefined types are (if you have ideas for additional types, feel free to
372drop by and tell us): 1039drop by and tell us):
373 1040
374=over 4 1041=over 4
376=item netstring => $string 1043=item netstring => $string
377 1044
378Formats the given value as netstring 1045Formats the given value as netstring
379(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 1046(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
380 1047
381=back
382
383=cut 1048=cut
384 1049
385register_write_type netstring => sub { 1050register_write_type netstring => sub {
386 my ($self, $string) = @_; 1051 my ($self, $string) = @_;
387 1052
388 sprintf "%d:%s,", (length $string), $string 1053 (length $string) . ":$string,"
1054};
1055
1056=item packstring => $format, $data
1057
1058An octet string prefixed with an encoded length. The encoding C<$format>
1059uses the same format as a Perl C<pack> format, but must specify a single
1060integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1061optional C<!>, C<< < >> or C<< > >> modifier).
1062
1063=cut
1064
1065register_write_type packstring => sub {
1066 my ($self, $format, $string) = @_;
1067
1068 pack "$format/a*", $string
389}; 1069};
390 1070
391=item json => $array_or_hashref 1071=item json => $array_or_hashref
392 1072
393Encodes the given hash or array reference into a JSON object. Unless you 1073Encodes the given hash or array reference into a JSON object. Unless you
394provide your own JSON object, this means it will be encoded to JSON text 1074provide your own JSON object, this means it will be encoded to JSON text
395in UTF-8. 1075in UTF-8.
396 1076
1077The default encoder might or might not handle every type of JSON value -
1078it might be limited to arrays and objects for security reasons. See the
1079C<json> constructor attribute for more details.
1080
397JSON objects (and arrays) are self-delimiting, so you can write JSON at 1081JSON objects (and arrays) are self-delimiting, so if you only use arrays
398one end of a handle and read them at the other end without using any 1082and hashes, you can write JSON at one end of a handle and read them at the
399additional framing. 1083other end without using any additional framing.
400 1084
401The generated JSON text is guaranteed not to contain any newlines: While 1085The JSON text generated by the default encoder is guaranteed not to
402this module doesn't need delimiters after or between JSON texts to be 1086contain any newlines: While this module doesn't need delimiters after or
403able to read them, many other languages depend on that. 1087between JSON texts to be able to read them, many other languages depend on
1088them.
404 1089
405A simple RPC protocol that interoperates easily with others is to send 1090A simple RPC protocol that interoperates easily with other languages is
406JSON arrays (or objects, although arrays are usually the better choice as 1091to send JSON arrays (or objects, although arrays are usually the better
407they mimic how function argument passing works) and a newline after each 1092choice as they mimic how function argument passing works) and a newline
408JSON text: 1093after each JSON text:
409 1094
410 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever 1095 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
411 $handle->push_write ("\012"); 1096 $handle->push_write ("\012");
412 1097
413An AnyEvent::Handle receiver would simply use the C<json> read type and 1098An AnyEvent::Handle receiver would simply use the C<json> read type and
416 $handle->push_read (json => sub { my $array = $_[1]; ... }); 1101 $handle->push_read (json => sub { my $array = $_[1]; ... });
417 1102
418Other languages could read single lines terminated by a newline and pass 1103Other languages could read single lines terminated by a newline and pass
419this line into their JSON decoder of choice. 1104this line into their JSON decoder of choice.
420 1105
1106=item cbor => $perl_scalar
1107
1108Encodes the given scalar into a CBOR value. Unless you provide your own
1109L<CBOR::XS> object, this means it will be encoded to a CBOR string not
1110using any extensions, if possible.
1111
1112CBOR values are self-delimiting, so you can write CBOR at one end of
1113a handle and read them at the other end without using any additional
1114framing.
1115
1116A simple nd very very fast RPC protocol that interoperates with
1117other languages is to send CBOR and receive CBOR values (arrays are
1118recommended):
1119
1120 $handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
1121
1122An AnyEvent::Handle receiver would simply use the C<cbor> read type:
1123
1124 $handle->push_read (cbor => sub { my $array = $_[1]; ... });
1125
421=cut 1126=cut
1127
1128sub json_coder() {
1129 eval { require JSON::XS; JSON::XS->new->utf8 }
1130 || do { require JSON::PP; JSON::PP->new->utf8 }
1131}
422 1132
423register_write_type json => sub { 1133register_write_type json => sub {
424 my ($self, $ref) = @_; 1134 my ($self, $ref) = @_;
425 1135
426 require JSON; 1136 ($self->{json} ||= json_coder)
427 1137 ->encode ($ref)
428 $self->{json} ? $self->{json}->encode ($ref)
429 : JSON::encode_json ($ref)
430}; 1138};
431 1139
432=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1140sub cbor_coder() {
1141 require CBOR::XS;
1142 CBOR::XS->new
1143}
433 1144
434This function (not method) lets you add your own types to C<push_write>. 1145register_write_type cbor => sub {
1146 my ($self, $scalar) = @_;
1147
1148 ($self->{cbor} ||= cbor_coder)
1149 ->encode ($scalar)
1150};
1151
1152=item storable => $reference
1153
1154Freezes the given reference using L<Storable> and writes it to the
1155handle. Uses the C<nfreeze> format.
1156
1157=cut
1158
1159register_write_type storable => sub {
1160 my ($self, $ref) = @_;
1161
1162 require Storable unless $Storable::VERSION;
1163
1164 pack "w/a*", Storable::nfreeze ($ref)
1165};
1166
1167=back
1168
1169=item $handle->push_shutdown
1170
1171Sometimes you know you want to close the socket after writing your data
1172before it was actually written. One way to do that is to replace your
1173C<on_drain> handler by a callback that shuts down the socket (and set
1174C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1175replaces the C<on_drain> callback with:
1176
1177 sub { shutdown $_[0]{fh}, 1 }
1178
1179This simply shuts down the write side and signals an EOF condition to the
1180the peer.
1181
1182You can rely on the normal read queue and C<on_eof> handling
1183afterwards. This is the cleanest way to close a connection.
1184
1185This method may invoke callbacks (and therefore the handle might be
1186destroyed after it returns).
1187
1188=cut
1189
1190sub push_shutdown {
1191 my ($self) = @_;
1192
1193 delete $self->{low_water_mark};
1194 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1195}
1196
1197=item custom write types - Package::anyevent_write_type $handle, @args
1198
1199Instead of one of the predefined types, you can also specify the name of
1200a package. AnyEvent will try to load the package and then expects to find
1201a function named C<anyevent_write_type> inside. If it isn't found, it
1202progressively tries to load the parent package until it either finds the
1203function (good) or runs out of packages (bad).
1204
435Whenever the given C<type> is used, C<push_write> will invoke the code 1205Whenever the given C<type> is used, C<push_write> will the function with
436reference with the handle object and the remaining arguments. 1206the handle object and the remaining arguments.
437 1207
438The code reference is supposed to return a single octet string that will 1208The function is supposed to return a single octet string that will be
439be appended to the write buffer. 1209appended to the write buffer, so you can mentally treat this function as a
1210"arguments to on-the-wire-format" converter.
440 1211
441Note that this is a function, and all types registered this way will be 1212Example: implement a custom write type C<join> that joins the remaining
442global, so try to use unique names. 1213arguments using the first one.
1214
1215 $handle->push_write (My::Type => " ", 1,2,3);
1216
1217 # uses the following package, which can be defined in the "My::Type" or in
1218 # the "My" modules to be auto-loaded, or just about anywhere when the
1219 # My::Type::anyevent_write_type is defined before invoking it.
1220
1221 package My::Type;
1222
1223 sub anyevent_write_type {
1224 my ($handle, $delim, @args) = @_;
1225
1226 join $delim, @args
1227 }
443 1228
444=cut 1229=cut
445 1230
446############################################################################# 1231#############################################################################
447 1232
456ways, the "simple" way, using only C<on_read> and the "complex" way, using 1241ways, the "simple" way, using only C<on_read> and the "complex" way, using
457a queue. 1242a queue.
458 1243
459In the simple case, you just install an C<on_read> callback and whenever 1244In 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 1245new 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 1246enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
462or not. 1247leave the data there if you want to accumulate more (e.g. when only a
1248partial message has been received so far), or change the read queue with
1249e.g. C<push_read>.
463 1250
464In the more complex case, you want to queue multiple callbacks. In this 1251In the more complex case, you want to queue multiple callbacks. In this
465case, AnyEvent::Handle will call the first queued callback each time new 1252case, 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>, 1253data arrives (also the first time it is queued) and remove it when it has
467below). 1254done its job (see C<push_read>, below).
468 1255
469This way you can, for example, push three line-reads, followed by reading 1256This way you can, for example, push three line-reads, followed by reading
470a chunk of data, and AnyEvent::Handle will execute them in order. 1257a chunk of data, and AnyEvent::Handle will execute them in order.
471 1258
472Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 1259Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
473the specified number of bytes which give an XML datagram. 1260the specified number of bytes which give an XML datagram.
474 1261
475 # in the default state, expect some header bytes 1262 # in the default state, expect some header bytes
476 $handle->on_read (sub { 1263 $handle->on_read (sub {
477 # some data is here, now queue the length-header-read (4 octets) 1264 # some data is here, now queue the length-header-read (4 octets)
478 shift->unshift_read_chunk (4, sub { 1265 shift->unshift_read (chunk => 4, sub {
479 # header arrived, decode 1266 # header arrived, decode
480 my $len = unpack "N", $_[1]; 1267 my $len = unpack "N", $_[1];
481 1268
482 # now read the payload 1269 # now read the payload
483 shift->unshift_read_chunk ($len, sub { 1270 shift->unshift_read (chunk => $len, sub {
484 my $xml = $_[1]; 1271 my $xml = $_[1];
485 # handle xml 1272 # handle xml
486 }); 1273 });
487 }); 1274 });
488 }); 1275 });
489 1276
490Example 2: Implement a client for a protocol that replies either with 1277Example 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 1278and 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 1279bytes for the second request. Due to the availability of a queue, we can
493pipeline sending both requests and manipulate the queue as necessary in 1280just pipeline sending both requests and manipulate the queue as necessary
494the callbacks: 1281in the callbacks.
495 1282
496 # request one 1283When the first callback is called and sees an "OK" response, it will
1284C<unshift> another line-read. This line-read will be queued I<before> the
128564-byte chunk callback.
1286
1287 # request one, returns either "OK + extra line" or "ERROR"
497 $handle->push_write ("request 1\015\012"); 1288 $handle->push_write ("request 1\015\012");
498 1289
499 # we expect "ERROR" or "OK" as response, so push a line read 1290 # we expect "ERROR" or "OK" as response, so push a line read
500 $handle->push_read_line (sub { 1291 $handle->push_read (line => sub {
501 # if we got an "OK", we have to _prepend_ another line, 1292 # if we got an "OK", we have to _prepend_ another line,
502 # so it will be read before the second request reads its 64 bytes 1293 # so it will be read before the second request reads its 64 bytes
503 # which are already in the queue when this callback is called 1294 # which are already in the queue when this callback is called
504 # we don't do this in case we got an error 1295 # we don't do this in case we got an error
505 if ($_[1] eq "OK") { 1296 if ($_[1] eq "OK") {
506 $_[0]->unshift_read_line (sub { 1297 $_[0]->unshift_read (line => sub {
507 my $response = $_[1]; 1298 my $response = $_[1];
508 ... 1299 ...
509 }); 1300 });
510 } 1301 }
511 }); 1302 });
512 1303
513 # request two 1304 # request two, simply returns 64 octets
514 $handle->push_write ("request 2\015\012"); 1305 $handle->push_write ("request 2\015\012");
515 1306
516 # simply read 64 bytes, always 1307 # simply read 64 bytes, always
517 $handle->push_read_chunk (64, sub { 1308 $handle->push_read (chunk => 64, sub {
518 my $response = $_[1]; 1309 my $response = $_[1];
519 ... 1310 ...
520 }); 1311 });
521 1312
522=over 4 1313=over 4
523 1314
524=cut 1315=cut
525 1316
526sub _drain_rbuf { 1317sub _drain_rbuf {
527 my ($self) = @_; 1318 my ($self) = @_;
1319
1320 # avoid recursion
1321 return if $self->{_skip_drain_rbuf};
1322 local $self->{_skip_drain_rbuf} = 1;
1323
1324 while () {
1325 # we need to use a separate tls read buffer, as we must not receive data while
1326 # we are draining the buffer, and this can only happen with TLS.
1327 $self->{rbuf} .= delete $self->{_tls_rbuf}
1328 if exists $self->{_tls_rbuf};
1329
1330 my $len = length $self->{rbuf};
1331
1332 if (my $cb = shift @{ $self->{_queue} }) {
1333 unless ($cb->($self)) {
1334 # no progress can be made
1335 # (not enough data and no data forthcoming)
1336 $self->_error (Errno::EPIPE, 1), return
1337 if $self->{_eof};
1338
1339 unshift @{ $self->{_queue} }, $cb;
1340 last;
1341 }
1342 } elsif ($self->{on_read}) {
1343 last unless $len;
1344
1345 $self->{on_read}($self);
1346
1347 if (
1348 $len == length $self->{rbuf} # if no data has been consumed
1349 && !@{ $self->{_queue} } # and the queue is still empty
1350 && $self->{on_read} # but we still have on_read
1351 ) {
1352 # no further data will arrive
1353 # so no progress can be made
1354 $self->_error (Errno::EPIPE, 1), return
1355 if $self->{_eof};
1356
1357 last; # more data might arrive
1358 }
1359 } else {
1360 # read side becomes idle
1361 delete $self->{_rw} unless $self->{tls};
1362 last;
1363 }
1364 }
1365
1366 if ($self->{_eof}) {
1367 $self->{on_eof}
1368 ? $self->{on_eof}($self)
1369 : $self->_error (0, 1, "Unexpected end-of-file");
1370
1371 return;
1372 }
528 1373
529 if ( 1374 if (
530 defined $self->{rbuf_max} 1375 defined $self->{rbuf_max}
531 && $self->{rbuf_max} < length $self->{rbuf} 1376 && $self->{rbuf_max} < length $self->{rbuf}
532 ) { 1377 ) {
533 $! = &Errno::ENOSPC; 1378 $self->_error (Errno::ENOSPC, 1), return;
534 $self->error;
535 } 1379 }
536 1380
537 return if $self->{in_drain}; 1381 # may need to restart read watcher
538 local $self->{in_drain} = 1; 1382 unless ($self->{_rw}) {
539 1383 $self->start_read
540 while (my $len = length $self->{rbuf}) { 1384 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 } 1385 }
578} 1386}
579 1387
580=item $handle->on_read ($cb) 1388=item $handle->on_read ($cb)
581 1389
582This replaces the currently set C<on_read> callback, or clears it (when 1390This 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 1391the new callback is C<undef>). See the description of C<on_read> in the
584constructor. 1392constructor.
585 1393
1394This method may invoke callbacks (and therefore the handle might be
1395destroyed after it returns).
1396
586=cut 1397=cut
587 1398
588sub on_read { 1399sub on_read {
589 my ($self, $cb) = @_; 1400 my ($self, $cb) = @_;
590 1401
591 $self->{on_read} = $cb; 1402 $self->{on_read} = $cb;
1403 $self->_drain_rbuf if $cb;
592} 1404}
593 1405
594=item $handle->rbuf 1406=item $handle->rbuf
595 1407
596Returns the read buffer (as a modifiable lvalue). 1408Returns the read buffer (as a modifiable lvalue). You can also access the
1409read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1410much faster, and no less clean).
597 1411
598You can access the read buffer directly as the C<< ->{rbuf} >> member, if 1412The only operation allowed on the read buffer (apart from looking at it)
599you want. 1413is removing data from its beginning. Otherwise modifying or appending to
1414it is not allowed and will lead to hard-to-track-down bugs.
600 1415
601NOTE: The read buffer should only be used or modified if the C<on_read>, 1416NOTE: 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 1417callback or when C<push_read> or C<unshift_read> are used with a single
603automatically manage the read buffer. 1418callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1419will manage the read buffer on their own.
604 1420
605=cut 1421=cut
606 1422
607sub rbuf : lvalue { 1423sub rbuf : lvalue {
608 $_[0]{rbuf} 1424 $_[0]{rbuf}
625 1441
626If enough data was available, then the callback must remove all data it is 1442If 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 1443interested in (which can be none at all) and return a true value. After returning
628true, it will be removed from the queue. 1444true, it will be removed from the queue.
629 1445
1446These methods may invoke callbacks (and therefore the handle might be
1447destroyed after it returns).
1448
630=cut 1449=cut
631 1450
632our %RH; 1451our %RH;
633 1452
634sub register_read_type($$) { 1453sub register_read_type($$) {
640 my $cb = pop; 1459 my $cb = pop;
641 1460
642 if (@_) { 1461 if (@_) {
643 my $type = shift; 1462 my $type = shift;
644 1463
1464 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
645 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1465 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
646 ->($self, $cb, @_); 1466 ->($self, $cb, @_);
647 } 1467 }
648 1468
649 push @{ $self->{_queue} }, $cb; 1469 push @{ $self->{_queue} }, $cb;
650 $self->_drain_rbuf; 1470 $self->_drain_rbuf;
655 my $cb = pop; 1475 my $cb = pop;
656 1476
657 if (@_) { 1477 if (@_) {
658 my $type = shift; 1478 my $type = shift;
659 1479
1480 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
660 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1481 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
661 ->($self, $cb, @_); 1482 ->($self, $cb, @_);
662 } 1483 }
663
664 1484
665 unshift @{ $self->{_queue} }, $cb; 1485 unshift @{ $self->{_queue} }, $cb;
666 $self->_drain_rbuf; 1486 $self->_drain_rbuf;
667} 1487}
668 1488
670 1490
671=item $handle->unshift_read (type => @args, $cb) 1491=item $handle->unshift_read (type => @args, $cb)
672 1492
673Instead of providing a callback that parses the data itself you can chose 1493Instead of providing a callback that parses the data itself you can chose
674between a number of predefined parsing formats, for chunks of data, lines 1494between a number of predefined parsing formats, for chunks of data, lines
675etc. 1495etc. You can also specify the (fully qualified) name of a package, in
1496which case AnyEvent tries to load the package and then expects to find the
1497C<anyevent_read_type> function inside (see "custom read types", below).
676 1498
677Predefined types are (if you have ideas for additional types, feel free to 1499Predefined types are (if you have ideas for additional types, feel free to
678drop by and tell us): 1500drop by and tell us):
679 1501
680=over 4 1502=over 4
686data. 1508data.
687 1509
688Example: read 2 bytes. 1510Example: read 2 bytes.
689 1511
690 $handle->push_read (chunk => 2, sub { 1512 $handle->push_read (chunk => 2, sub {
691 warn "yay ", unpack "H*", $_[1]; 1513 say "yay " . unpack "H*", $_[1];
692 }); 1514 });
693 1515
694=cut 1516=cut
695 1517
696register_read_type chunk => sub { 1518register_read_type chunk => sub {
701 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 1523 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
702 1 1524 1
703 } 1525 }
704}; 1526};
705 1527
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, $eol) 1528=item line => [$eol, ]$cb->($handle, $line, $eol)
716 1529
717The callback will be called only once a full line (including the end of 1530The callback will be called only once a full line (including the end of
718line marker, C<$eol>) has been read. This line (excluding the end of line 1531line 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 1532marker) will be passed to the callback as second argument (C<$line>), and
734=cut 1547=cut
735 1548
736register_read_type line => sub { 1549register_read_type line => sub {
737 my ($self, $cb, $eol) = @_; 1550 my ($self, $cb, $eol) = @_;
738 1551
739 $eol = qr|(\015?\012)| if @_ < 3; 1552 if (@_ < 3) {
740 $eol = quotemeta $eol unless ref $eol; 1553 # this is faster then the generic code below
741 $eol = qr|^(.*?)($eol)|s;
742
743 sub { 1554 sub {
744 $_[0]{rbuf} =~ s/$eol// or return; 1555 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1556 or return;
745 1557
1558 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
746 $cb->($_[0], $1, $2); 1559 $cb->($_[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 } 1560 1
779 return;
780 } 1561 }
1562 } else {
1563 $eol = quotemeta $eol unless ref $eol;
1564 $eol = qr|^(.*?)($eol)|s;
781 1565
782 my $len = $1; 1566 sub {
1567 $_[0]{rbuf} =~ s/$eol// or return;
783 1568
784 $self->unshift_read (chunk => $len, sub { 1569 $cb->($_[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 }); 1570 1
794 }); 1571 }
795
796 1
797 } 1572 }
798}; 1573};
799 1574
800=item regex => $accept[, $reject[, $skip], $cb->($handle, $data) 1575=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
801 1576
821the receive buffer when neither C<$accept> nor C<$reject> match, 1596the receive buffer when neither C<$accept> nor C<$reject> match,
822and everything preceding and including the match will be accepted 1597and everything preceding and including the match will be accepted
823unconditionally. This is useful to skip large amounts of data that you 1598unconditionally. This is useful to skip large amounts of data that you
824know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1599know cannot be matched, so that the C<$accept> or C<$reject> regex do not
825have to start matching from the beginning. This is purely an optimisation 1600have to start matching from the beginning. This is purely an optimisation
826and is usually worth only when you expect more than a few kilobytes. 1601and is usually worth it only when you expect more than a few kilobytes.
827 1602
828Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1603Example: 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 1604expect 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 1605a 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 1606it only accepts something not ending in either \015 or \012, as these are
832required for the accept regex. 1607required for the accept regex.
833 1608
834 $handle->push_read (regex => 1609 $handle->push_read (regex =>
847 1622
848 sub { 1623 sub {
849 # accept 1624 # accept
850 if ($$rbuf =~ $accept) { 1625 if ($$rbuf =~ $accept) {
851 $data .= substr $$rbuf, 0, $+[0], ""; 1626 $data .= substr $$rbuf, 0, $+[0], "";
852 $cb->($self, $data); 1627 $cb->($_[0], $data);
853 return 1; 1628 return 1;
854 } 1629 }
855 1630
856 # reject 1631 # reject
857 if ($reject && $$rbuf =~ $reject) { 1632 if ($reject && $$rbuf =~ $reject) {
858 $! = &Errno::EBADMSG; 1633 $_[0]->_error (Errno::EBADMSG);
859 $self->error;
860 } 1634 }
861 1635
862 # skip 1636 # skip
863 if ($skip && $$rbuf =~ $skip) { 1637 if ($skip && $$rbuf =~ $skip) {
864 $data .= substr $$rbuf, 0, $+[0], ""; 1638 $data .= substr $$rbuf, 0, $+[0], "";
866 1640
867 () 1641 ()
868 } 1642 }
869}; 1643};
870 1644
1645=item netstring => $cb->($handle, $string)
1646
1647A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1648
1649Throws an error with C<$!> set to EBADMSG on format violations.
1650
1651=cut
1652
1653register_read_type netstring => sub {
1654 my ($self, $cb) = @_;
1655
1656 sub {
1657 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1658 if ($_[0]{rbuf} =~ /[^0-9]/) {
1659 $_[0]->_error (Errno::EBADMSG);
1660 }
1661 return;
1662 }
1663
1664 my $len = $1;
1665
1666 $_[0]->unshift_read (chunk => $len, sub {
1667 my $string = $_[1];
1668 $_[0]->unshift_read (chunk => 1, sub {
1669 if ($_[1] eq ",") {
1670 $cb->($_[0], $string);
1671 } else {
1672 $_[0]->_error (Errno::EBADMSG);
1673 }
1674 });
1675 });
1676
1677 1
1678 }
1679};
1680
1681=item packstring => $format, $cb->($handle, $string)
1682
1683An octet string prefixed with an encoded length. The encoding C<$format>
1684uses the same format as a Perl C<pack> format, but must specify a single
1685integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1686optional C<!>, C<< < >> or C<< > >> modifier).
1687
1688For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1689EPP uses a prefix of C<N> (4 octtes).
1690
1691Example: read a block of data prefixed by its length in BER-encoded
1692format (very efficient).
1693
1694 $handle->push_read (packstring => "w", sub {
1695 my ($handle, $data) = @_;
1696 });
1697
1698=cut
1699
1700register_read_type packstring => sub {
1701 my ($self, $cb, $format) = @_;
1702
1703 sub {
1704 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1705 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1706 or return;
1707
1708 $format = length pack $format, $len;
1709
1710 # bypass unshift if we already have the remaining chunk
1711 if ($format + $len <= length $_[0]{rbuf}) {
1712 my $data = substr $_[0]{rbuf}, $format, $len;
1713 substr $_[0]{rbuf}, 0, $format + $len, "";
1714 $cb->($_[0], $data);
1715 } else {
1716 # remove prefix
1717 substr $_[0]{rbuf}, 0, $format, "";
1718
1719 # read remaining chunk
1720 $_[0]->unshift_read (chunk => $len, $cb);
1721 }
1722
1723 1
1724 }
1725};
1726
871=item json => $cb->($handle, $hash_or_arrayref) 1727=item json => $cb->($handle, $hash_or_arrayref)
872 1728
873Reads a JSON object or array, decodes it and passes it to the callback. 1729Reads a JSON object or array, decodes it and passes it to the
1730callback. When a parse error occurs, an C<EBADMSG> error will be raised.
874 1731
875If a C<json> object was passed to the constructor, then that will be used 1732If a C<json> object was passed to the constructor, then that will be
876for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1733used for the final decode, otherwise it will create a L<JSON::XS> or
1734L<JSON::PP> coder object expecting UTF-8.
877 1735
878This read type uses the incremental parser available with JSON version 1736This read type uses the incremental parser available with JSON version
8792.09 (and JSON::XS version 2.2) and above. You have to provide a 17372.09 (and JSON::XS version 2.2) and above.
880dependency on your own: this module will load the JSON module, but
881AnyEvent does not depend on it itself.
882 1738
883Since JSON texts are fully self-delimiting, the C<json> read and write 1739Since JSON texts are fully self-delimiting, the C<json> read and write
884types are an ideal simple RPC protocol: just exchange JSON datagrams. See 1740types are an ideal simple RPC protocol: just exchange JSON datagrams. See
885the C<json> write type description, above, for an actual example. 1741the C<json> write type description, above, for an actual example.
886 1742
887=cut 1743=cut
888 1744
889register_read_type json => sub { 1745register_read_type json => sub {
890 my ($self, $cb, $accept, $reject, $skip) = @_; 1746 my ($self, $cb) = @_;
891 1747
892 require JSON; 1748 my $json = $self->{json} ||= json_coder;
893 1749
894 my $data; 1750 my $data;
895 my $rbuf = \$self->{rbuf};
896
897 my $json = $self->{json} ||= JSON->new->utf8;
898 1751
899 sub { 1752 sub {
900 my $ref = $json->incr_parse ($self->{rbuf}); 1753 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
901 1754
902 if ($ref) { 1755 if ($ref) {
903 $self->{rbuf} = $json->incr_text; 1756 $_[0]{rbuf} = $json->incr_text;
904 $json->incr_text = ""; 1757 $json->incr_text = "";
905 $cb->($self, $ref); 1758 $cb->($_[0], $ref);
906 1759
907 1 1760 1
1761 } elsif ($@) {
1762 # error case
1763 $json->incr_skip;
1764
1765 $_[0]{rbuf} = $json->incr_text;
1766 $json->incr_text = "";
1767
1768 $_[0]->_error (Errno::EBADMSG);
1769
1770 ()
908 } else { 1771 } else {
909 $self->{rbuf} = ""; 1772 $_[0]{rbuf} = "";
1773
910 () 1774 ()
911 } 1775 }
912 } 1776 }
913}; 1777};
914 1778
1779=item cbor => $cb->($handle, $scalar)
1780
1781Reads a CBOR value, decodes it and passes it to the callback. When a parse
1782error occurs, an C<EBADMSG> error will be raised.
1783
1784If a L<CBOR::XS> object was passed to the constructor, then that will be
1785used for the final decode, otherwise it will create a CBOR coder without
1786enabling any options.
1787
1788You have to provide a dependency to L<CBOR::XS> on your own: this module
1789will load the L<CBOR::XS> module, but AnyEvent does not depend on it
1790itself.
1791
1792Since CBOR values are fully self-delimiting, the C<cbor> read and write
1793types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
1794the C<cbor> write type description, above, for an actual example.
1795
1796=cut
1797
1798register_read_type cbor => sub {
1799 my ($self, $cb) = @_;
1800
1801 my $cbor = $self->{cbor} ||= cbor_coder;
1802
1803 my $data;
1804
1805 sub {
1806 my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
1807
1808 if (@value) {
1809 $cb->($_[0], @value);
1810
1811 1
1812 } elsif ($@) {
1813 # error case
1814 $cbor->incr_reset;
1815
1816 $_[0]->_error (Errno::EBADMSG);
1817
1818 ()
1819 } else {
1820 ()
1821 }
1822 }
1823};
1824
1825=item storable => $cb->($handle, $ref)
1826
1827Deserialises a L<Storable> frozen representation as written by the
1828C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1829data).
1830
1831Raises C<EBADMSG> error if the data could not be decoded.
1832
1833=cut
1834
1835register_read_type storable => sub {
1836 my ($self, $cb) = @_;
1837
1838 require Storable unless $Storable::VERSION;
1839
1840 sub {
1841 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1842 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1843 or return;
1844
1845 my $format = length pack "w", $len;
1846
1847 # bypass unshift if we already have the remaining chunk
1848 if ($format + $len <= length $_[0]{rbuf}) {
1849 my $data = substr $_[0]{rbuf}, $format, $len;
1850 substr $_[0]{rbuf}, 0, $format + $len, "";
1851
1852 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1853 or return $_[0]->_error (Errno::EBADMSG);
1854 } else {
1855 # remove prefix
1856 substr $_[0]{rbuf}, 0, $format, "";
1857
1858 # read remaining chunk
1859 $_[0]->unshift_read (chunk => $len, sub {
1860 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1861 or $_[0]->_error (Errno::EBADMSG);
1862 });
1863 }
1864
1865 1
1866 }
1867};
1868
1869=item tls_detect => $cb->($handle, $detect, $major, $minor)
1870
1871Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1872record without consuming anything. Only SSL version 3 or higher
1873is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1874SSL2-compatible framing is supported).
1875
1876If it detects that the input data is likely TLS, it calls the callback
1877with a true value for C<$detect> and the (on-wire) TLS version as second
1878and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
18793.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1880be definitely not TLS, it calls the callback with a false value for
1881C<$detect>.
1882
1883The callback could use this information to decide whether or not to start
1884TLS negotiation.
1885
1886In all cases the data read so far is passed to the following read
1887handlers.
1888
1889Usually you want to use the C<tls_autostart> read type instead.
1890
1891If you want to design a protocol that works in the presence of TLS
1892dtection, make sure that any non-TLS data doesn't start with the octet 22
1893(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1894read type does are a bit more strict, but might losen in the future to
1895accomodate protocol changes.
1896
1897This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1898L<Net::SSLeay>).
1899
1900=item tls_autostart => $tls[, $tls_ctx]
1901
1902Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1903to start tls by calling C<starttls> with the given arguments.
1904
1905In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1906been configured to accept, as servers do not normally send a handshake on
1907their own and ths cannot be detected in this way.
1908
1909See C<tls_detect> above for more details.
1910
1911Example: give the client a chance to start TLS before accepting a text
1912line.
1913
1914 $hdl->push_read (tls_detect => "accept");
1915 $hdl->push_read (line => sub {
1916 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1917 });
1918
1919=cut
1920
1921register_read_type tls_detect => sub {
1922 my ($self, $cb) = @_;
1923
1924 sub {
1925 # this regex matches a full or partial tls record
1926 if (
1927 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1928 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1929 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1930 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1931 ) {
1932 return if 3 != length $1; # partial match, can't decide yet
1933
1934 # full match, valid TLS record
1935 my ($major, $minor) = unpack "CC", $1;
1936 $cb->($self, "accept", $major + $minor * 0.1);
1937 } else {
1938 # mismatch == guaranteed not TLS
1939 $cb->($self, undef);
1940 }
1941
1942 1
1943 }
1944};
1945
1946register_read_type tls_autostart => sub {
1947 my ($self, @tls) = @_;
1948
1949 $RH{tls_detect}($self, sub {
1950 return unless $_[1];
1951 $_[0]->starttls (@tls);
1952 })
1953};
1954
915=back 1955=back
916 1956
917=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1957=item custom read types - Package::anyevent_read_type $handle, $cb, @args
918 1958
919This function (not method) lets you add your own types to C<push_read>. 1959Instead of one of the predefined types, you can also specify the name
1960of a package. AnyEvent will try to load the package and then expects to
1961find a function named C<anyevent_read_type> inside. If it isn't found, it
1962progressively tries to load the parent package until it either finds the
1963function (good) or runs out of packages (bad).
920 1964
921Whenever the given C<type> is used, C<push_read> will invoke the code 1965Whenever this type is used, C<push_read> will invoke the function with the
922reference with the handle object, the callback and the remaining 1966handle object, the original callback and the remaining arguments.
923arguments.
924 1967
925The code reference is supposed to return a callback (usually a closure) 1968The function is supposed to return a callback (usually a closure) that
926that works as a plain read callback (see C<< ->push_read ($cb) >>). 1969works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1970mentally treat the function as a "configurable read type to read callback"
1971converter.
927 1972
928It should invoke the passed callback when it is done reading (remember to 1973It should invoke the original callback when it is done reading (remember
929pass C<$handle> as first argument as all other callbacks do that). 1974to pass C<$handle> as first argument as all other callbacks do that,
1975although there is no strict requirement on this).
930 1976
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>, 1977For examples, see the source of this module (F<perldoc -m
935search for C<register_read_type>)). 1978AnyEvent::Handle>, search for C<register_read_type>)).
936 1979
937=item $handle->stop_read 1980=item $handle->stop_read
938 1981
939=item $handle->start_read 1982=item $handle->start_read
940 1983
941In rare cases you actually do not want to read anything from the 1984In rare cases you actually do not want to read anything from the
942socket. In this case you can call C<stop_read>. Neither C<on_read> no 1985socket. In this case you can call C<stop_read>. Neither C<on_read> nor
943any queued callbacks will be executed then. To start reading again, call 1986any queued callbacks will be executed then. To start reading again, call
944C<start_read>. 1987C<start_read>.
945 1988
1989Note that AnyEvent::Handle will automatically C<start_read> for you when
1990you change the C<on_read> callback or push/unshift a read callback, and it
1991will automatically C<stop_read> for you when neither C<on_read> is set nor
1992there are any read requests in the queue.
1993
1994In older versions of this module (<= 5.3), these methods had no effect,
1995as TLS does not support half-duplex connections. In current versions they
1996work as expected, as this behaviour is required to avoid certain resource
1997attacks, where the program would be forced to read (and buffer) arbitrary
1998amounts of data before being able to send some data. The drawback is that
1999some readings of the the SSL/TLS specifications basically require this
2000attack to be working, as SSL/TLS implementations might stall sending data
2001during a rehandshake.
2002
2003As a guideline, during the initial handshake, you should not stop reading,
2004and as a client, it might cause problems, depending on your application.
2005
946=cut 2006=cut
947 2007
948sub stop_read { 2008sub stop_read {
949 my ($self) = @_; 2009 my ($self) = @_;
950 2010
952} 2012}
953 2013
954sub start_read { 2014sub start_read {
955 my ($self) = @_; 2015 my ($self) = @_;
956 2016
957 unless ($self->{_rw} || $self->{_eof}) { 2017 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
958 Scalar::Util::weaken $self; 2018 Scalar::Util::weaken $self;
959 2019
960 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 2020 $self->{_rw} = AE::io $self->{fh}, 0, sub {
961 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 2021 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
962 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 2022 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
963 2023
964 if ($len > 0) { 2024 if ($len > 0) {
965 $self->{filter_r} 2025 $self->{_activity} = $self->{_ractivity} = AE::now;
966 ? $self->{filter_r}->($self, $rbuf) 2026
2027 if ($self->{tls}) {
2028 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
2029
2030 &_dotls ($self);
2031 } else {
967 : $self->_drain_rbuf; 2032 $self->_drain_rbuf;
2033 }
2034
2035 if ($len == $self->{read_size}) {
2036 $self->{read_size} *= 2;
2037 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
2038 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
2039 }
968 2040
969 } elsif (defined $len) { 2041 } elsif (defined $len) {
970 delete $self->{_rw}; 2042 delete $self->{_rw};
971 $self->{_eof} = 1; 2043 $self->{_eof} = 1;
972 $self->_drain_rbuf; 2044 $self->_drain_rbuf;
973 2045
974 } elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) { 2046 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
975 return $self->error; 2047 return $self->_error ($!, 1);
976 } 2048 }
977 }); 2049 };
978 } 2050 }
979} 2051}
980 2052
2053our $ERROR_SYSCALL;
2054our $ERROR_WANT_READ;
2055
2056sub _tls_error {
2057 my ($self, $err) = @_;
2058
2059 return $self->_error ($!, 1)
2060 if $err == Net::SSLeay::ERROR_SYSCALL ();
2061
2062 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
2063
2064 # reduce error string to look less scary
2065 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
2066
2067 if ($self->{_on_starttls}) {
2068 (delete $self->{_on_starttls})->($self, undef, $err);
2069 &_freetls;
2070 } else {
2071 &_freetls;
2072 $self->_error (Errno::EPROTO, 1, $err);
2073 }
2074}
2075
2076# poll the write BIO and send the data if applicable
2077# also decode read data if possible
2078# this is basiclaly our TLS state machine
2079# more efficient implementations are possible with openssl,
2080# but not with the buggy and incomplete Net::SSLeay.
981sub _dotls { 2081sub _dotls {
982 my ($self) = @_; 2082 my ($self) = @_;
983 2083
2084 my $tmp;
2085
984 if (length $self->{_tls_wbuf}) { 2086 while (length $self->{_tls_wbuf}) {
985 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 2087 if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
986 substr $self->{_tls_wbuf}, 0, $len, ""; 2088 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
2089
2090 return $self->_tls_error ($tmp)
2091 if $tmp != $ERROR_WANT_READ
2092 && ($tmp != $ERROR_SYSCALL || $!);
2093
2094 last;
987 } 2095 }
988 }
989 2096
2097 substr $self->{_tls_wbuf}, 0, $tmp, "";
2098 }
2099
2100 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
2101 unless (length $tmp) {
2102 $self->{_on_starttls}
2103 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
2104 &_freetls;
2105
2106 if ($self->{on_stoptls}) {
2107 $self->{on_stoptls}($self);
2108 return;
2109 } else {
2110 # let's treat SSL-eof as we treat normal EOF
2111 delete $self->{_rw};
2112 $self->{_eof} = 1;
2113 }
2114 }
2115
2116 $self->{_tls_rbuf} .= $tmp;
2117 $self->_drain_rbuf;
2118 $self->{tls} or return; # tls session might have gone away in callback
2119 }
2120
2121 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
2122 return $self->_tls_error ($tmp)
2123 if $tmp != $ERROR_WANT_READ
2124 && ($tmp != $ERROR_SYSCALL || $!);
2125
990 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2126 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
991 $self->{wbuf} .= $buf; 2127 $self->{wbuf} .= $tmp;
992 $self->_drain_wbuf; 2128 $self->_drain_wbuf;
2129 $self->{tls} or return; # tls session might have gone away in callback
993 } 2130 }
994 2131
995 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) { 2132 $self->{_on_starttls}
996 $self->{rbuf} .= $buf; 2133 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
997 $self->_drain_rbuf; 2134 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} 2135}
1013 2136
1014=item $handle->starttls ($tls[, $tls_ctx]) 2137=item $handle->starttls ($tls[, $tls_ctx])
1015 2138
1016Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2139Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1017object is created, you can also do that at a later time by calling 2140object is created, you can also do that at a later time by calling
1018C<starttls>. 2141C<starttls>. See the C<tls> constructor argument for general info.
2142
2143Starting TLS is currently an asynchronous operation - when you push some
2144write data and then call C<< ->starttls >> then TLS negotiation will start
2145immediately, after which the queued write data is then sent. This might
2146change in future versions, so best make sure you have no outstanding write
2147data when calling this method.
1019 2148
1020The first argument is the same as the C<tls> constructor argument (either 2149The first argument is the same as the C<tls> constructor argument (either
1021C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2150C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1022 2151
1023The second argument is the optional C<Net::SSLeay::CTX> object that is 2152The second argument is the optional C<AnyEvent::TLS> object that is used
1024used when AnyEvent::Handle has to create its own TLS connection object. 2153when AnyEvent::Handle has to create its own TLS connection object, or
2154a hash reference with C<< key => value >> pairs that will be used to
2155construct a new context.
1025 2156
1026The TLS connection object will end up in C<< $handle->{tls} >> after this 2157The 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 2158context in C<< $handle->{tls_ctx} >> after this call and can be used or
1028might have already started when this function returns. 2159changed to your liking. Note that the handshake might have already started
2160when this function returns.
1029 2161
1030=cut 2162Due to bugs in OpenSSL, it might or might not be possible to do multiple
2163handshakes on the same stream. It is best to not attempt to use the
2164stream after stopping TLS.
1031 2165
1032# TODO: maybe document... 2166This method may invoke callbacks (and therefore the handle might be
2167destroyed after it returns).
2168
2169=cut
2170
2171our %TLS_CACHE; #TODO not yet documented, should we?
2172
1033sub starttls { 2173sub starttls {
1034 my ($self, $ssl, $ctx) = @_; 2174 my ($self, $tls, $ctx) = @_;
1035 2175
1036 $self->stoptls; 2176 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
2177 if $self->{tls};
1037 2178
1038 if ($ssl eq "accept") { 2179 unless (defined $AnyEvent::TLS::VERSION) {
1039 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 2180 eval {
1040 Net::SSLeay::set_accept_state ($ssl); 2181 require Net::SSLeay;
1041 } elsif ($ssl eq "connect") { 2182 require AnyEvent::TLS;
1042 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 2183 1
1043 Net::SSLeay::set_connect_state ($ssl); 2184 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2185 }
2186
2187 $self->{tls} = $tls;
2188 $self->{tls_ctx} = $ctx if @_ > 2;
2189
2190 return unless $self->{fh};
2191
2192 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
2193 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
2194
2195 $tls = delete $self->{tls};
2196 $ctx = $self->{tls_ctx};
2197
2198 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
2199
2200 if ("HASH" eq ref $ctx) {
2201 if ($ctx->{cache}) {
2202 my $key = $ctx+0;
2203 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
2204 } else {
2205 $ctx = new AnyEvent::TLS %$ctx;
2206 }
2207 }
1044 } 2208
1045 2209 $self->{tls_ctx} = $ctx || TLS_CTX ();
1046 $self->{tls} = $ssl; 2210 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1047 2211
1048 # basically, this is deep magic (because SSL_read should have the same issues) 2212 # basically, this is deep magic (because SSL_read should have the same issues)
1049 # but the openssl maintainers basically said: "trust us, it just works". 2213 # but the openssl maintainers basically said: "trust us, it just works".
1050 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2214 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1051 # and mismaintained ssleay-module doesn't even offer them). 2215 # and mismaintained ssleay-module doesn't even offer them).
1052 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 2216 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
2217 #
2218 # in short: this is a mess.
2219 #
2220 # note that we do not try to keep the length constant between writes as we are required to do.
2221 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
2222 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
2223 # have identity issues in that area.
1053 Net::SSLeay::CTX_set_mode ($self->{tls}, 2224# Net::SSLeay::CTX_set_mode ($ssl,
1054 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2225# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1055 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2226# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
2227 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1056 2228
1057 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2229 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1058 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2230 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1059 2231
2232 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2233 $self->{rbuf} = "";
2234
1060 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2235 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1061 2236
1062 $self->{filter_w} = sub { 2237 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1063 $_[0]{_tls_wbuf} .= ${$_[1]}; 2238 if $self->{on_starttls};
1064 &_dotls; 2239
1065 }; 2240 &_dotls; # need to trigger the initial handshake
1066 $self->{filter_r} = sub { 2241 $self->start_read; # make sure we actually do read
1067 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1068 &_dotls;
1069 };
1070} 2242}
1071 2243
1072=item $handle->stoptls 2244=item $handle->stoptls
1073 2245
1074Destroys the SSL connection, if any. Partial read or write data will be 2246Shuts down the SSL connection - this makes a proper EOF handshake by
1075lost. 2247sending a close notify to the other side, but since OpenSSL doesn't
2248support non-blocking shut downs, it is not guaranteed that you can re-use
2249the stream afterwards.
2250
2251This method may invoke callbacks (and therefore the handle might be
2252destroyed after it returns).
1076 2253
1077=cut 2254=cut
1078 2255
1079sub stoptls { 2256sub stoptls {
1080 my ($self) = @_; 2257 my ($self) = @_;
1081 2258
1082 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 2259 if ($self->{tls} && $self->{fh}) {
2260 Net::SSLeay::shutdown ($self->{tls});
1083 2261
1084 delete $self->{_rbio}; 2262 &_dotls;
1085 delete $self->{_wbio}; 2263
1086 delete $self->{_tls_wbuf}; 2264# # we don't give a shit. no, we do, but we can't. no...#d#
1087 delete $self->{filter_r}; 2265# # we, we... have to use openssl :/#d#
1088 delete $self->{filter_w}; 2266# &_freetls;#d#
2267 }
1089} 2268}
2269
2270sub _freetls {
2271 my ($self) = @_;
2272
2273 return unless $self->{tls};
2274
2275 $self->{tls_ctx}->_put_session (delete $self->{tls})
2276 if $self->{tls} > 0;
2277
2278 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2279}
2280
2281=item $handle->resettls
2282
2283This rarely-used method simply resets and TLS state on the handle, usually
2284causing data loss.
2285
2286One case where it may be useful is when you want to skip over the data in
2287the stream but you are not interested in interpreting it, so data loss is
2288no concern.
2289
2290=cut
2291
2292*resettls = \&_freetls;
1090 2293
1091sub DESTROY { 2294sub DESTROY {
1092 my $self = shift; 2295 my ($self) = @_;
1093 2296
1094 $self->stoptls; 2297 &_freetls;
2298
2299 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
2300
2301 if ($linger && length $self->{wbuf} && $self->{fh}) {
2302 my $fh = delete $self->{fh};
2303 my $wbuf = delete $self->{wbuf};
2304
2305 my @linger;
2306
2307 push @linger, AE::io $fh, 1, sub {
2308 my $len = syswrite $fh, $wbuf, length $wbuf;
2309
2310 if ($len > 0) {
2311 substr $wbuf, 0, $len, "";
2312 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
2313 @linger = (); # end
2314 }
2315 };
2316 push @linger, AE::timer $linger, 0, sub {
2317 @linger = ();
2318 };
2319 }
1095} 2320}
2321
2322=item $handle->destroy
2323
2324Shuts down the handle object as much as possible - this call ensures that
2325no further callbacks will be invoked and as many resources as possible
2326will be freed. Any method you will call on the handle object after
2327destroying it in this way will be silently ignored (and it will return the
2328empty list).
2329
2330Normally, you can just "forget" any references to an AnyEvent::Handle
2331object and it will simply shut down. This works in fatal error and EOF
2332callbacks, as well as code outside. It does I<NOT> work in a read or write
2333callback, so when you want to destroy the AnyEvent::Handle object from
2334within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
2335that case.
2336
2337Destroying the handle object in this way has the advantage that callbacks
2338will be removed as well, so if those are the only reference holders (as
2339is common), then one doesn't need to do anything special to break any
2340reference cycles.
2341
2342The handle might still linger in the background and write out remaining
2343data, as specified by the C<linger> option, however.
2344
2345=cut
2346
2347sub destroy {
2348 my ($self) = @_;
2349
2350 $self->DESTROY;
2351 %$self = ();
2352 bless $self, "AnyEvent::Handle::destroyed";
2353}
2354
2355sub AnyEvent::Handle::destroyed::AUTOLOAD {
2356 #nop
2357}
2358
2359=item $handle->destroyed
2360
2361Returns false as long as the handle hasn't been destroyed by a call to C<<
2362->destroy >>, true otherwise.
2363
2364Can be useful to decide whether the handle is still valid after some
2365callback possibly destroyed the handle. For example, C<< ->push_write >>,
2366C<< ->starttls >> and other methods can call user callbacks, which in turn
2367can destroy the handle, so work can be avoided by checking sometimes:
2368
2369 $hdl->starttls ("accept");
2370 return if $hdl->destroyed;
2371 $hdl->push_write (...
2372
2373Note that the call to C<push_write> will silently be ignored if the handle
2374has been destroyed, so often you can just ignore the possibility of the
2375handle being destroyed.
2376
2377=cut
2378
2379sub destroyed { 0 }
2380sub AnyEvent::Handle::destroyed::destroyed { 1 }
1096 2381
1097=item AnyEvent::Handle::TLS_CTX 2382=item AnyEvent::Handle::TLS_CTX
1098 2383
1099This function creates and returns the Net::SSLeay::CTX object used by 2384This function creates and returns the AnyEvent::TLS object used by default
1100default for TLS mode. 2385for TLS mode.
1101 2386
1102The context is created like this: 2387The 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 2388
1112=cut 2389=cut
1113 2390
1114our $TLS_CTX; 2391our $TLS_CTX;
1115 2392
1116sub TLS_CTX() { 2393sub TLS_CTX() {
1117 $TLS_CTX || do { 2394 $TLS_CTX ||= do {
1118 require Net::SSLeay; 2395 require AnyEvent::TLS;
1119 2396
1120 Net::SSLeay::load_error_strings (); 2397 new AnyEvent::TLS
1121 Net::SSLeay::SSLeay_add_ssl_algorithms (); 2398 }
1122 Net::SSLeay::randomize (); 2399}
1123 2400
1124 $TLS_CTX = Net::SSLeay::CTX_new (); 2401=back
1125 2402
1126 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1127 2403
1128 $TLS_CTX 2404=head1 NONFREQUENTLY ASKED QUESTIONS
2405
2406=over 4
2407
2408=item I C<undef> the AnyEvent::Handle reference inside my callback and
2409still get further invocations!
2410
2411That's because AnyEvent::Handle keeps a reference to itself when handling
2412read or write callbacks.
2413
2414It is only safe to "forget" the reference inside EOF or error callbacks,
2415from within all other callbacks, you need to explicitly call the C<<
2416->destroy >> method.
2417
2418=item Why is my C<on_eof> callback never called?
2419
2420Probably because your C<on_error> callback is being called instead: When
2421you have outstanding requests in your read queue, then an EOF is
2422considered an error as you clearly expected some data.
2423
2424To avoid this, make sure you have an empty read queue whenever your handle
2425is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2426an C<on_read> handler that simply pushes the first read requests in the
2427queue.
2428
2429See also the next question, which explains this in a bit more detail.
2430
2431=item How can I serve requests in a loop?
2432
2433Most protocols consist of some setup phase (authentication for example)
2434followed by a request handling phase, where the server waits for requests
2435and handles them, in a loop.
2436
2437There are two important variants: The first (traditional, better) variant
2438handles requests until the server gets some QUIT command, causing it to
2439close the connection first (highly desirable for a busy TCP server). A
2440client dropping the connection is an error, which means this variant can
2441detect an unexpected detection close.
2442
2443To handle this case, always make sure you have a non-empty read queue, by
2444pushing the "read request start" handler on it:
2445
2446 # we assume a request starts with a single line
2447 my @start_request; @start_request = (line => sub {
2448 my ($hdl, $line) = @_;
2449
2450 ... handle request
2451
2452 # push next request read, possibly from a nested callback
2453 $hdl->push_read (@start_request);
2454 });
2455
2456 # auth done, now go into request handling loop
2457 # now push the first @start_request
2458 $hdl->push_read (@start_request);
2459
2460By always having an outstanding C<push_read>, the handle always expects
2461some data and raises the C<EPIPE> error when the connction is dropped
2462unexpectedly.
2463
2464The second variant is a protocol where the client can drop the connection
2465at any time. For TCP, this means that the server machine may run out of
2466sockets easier, and in general, it means you cannot distinguish a protocl
2467failure/client crash from a normal connection close. Nevertheless, these
2468kinds of protocols are common (and sometimes even the best solution to the
2469problem).
2470
2471Having an outstanding read request at all times is possible if you ignore
2472C<EPIPE> errors, but this doesn't help with when the client drops the
2473connection during a request, which would still be an error.
2474
2475A better solution is to push the initial request read in an C<on_read>
2476callback. This avoids an error, as when the server doesn't expect data
2477(i.e. is idly waiting for the next request, an EOF will not raise an
2478error, but simply result in an C<on_eof> callback. It is also a bit slower
2479and simpler:
2480
2481 # auth done, now go into request handling loop
2482 $hdl->on_read (sub {
2483 my ($hdl) = @_;
2484
2485 # called each time we receive data but the read queue is empty
2486 # simply start read the request
2487
2488 $hdl->push_read (line => sub {
2489 my ($hdl, $line) = @_;
2490
2491 ... handle request
2492
2493 # do nothing special when the request has been handled, just
2494 # let the request queue go empty.
2495 });
2496 });
2497
2498=item I get different callback invocations in TLS mode/Why can't I pause
2499reading?
2500
2501Unlike, say, TCP, TLS connections do not consist of two independent
2502communication channels, one for each direction. Or put differently, the
2503read and write directions are not independent of each other: you cannot
2504write data unless you are also prepared to read, and vice versa.
2505
2506This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2507callback invocations when you are not expecting any read data - the reason
2508is that AnyEvent::Handle always reads in TLS mode.
2509
2510During the connection, you have to make sure that you always have a
2511non-empty read-queue, or an C<on_read> watcher. At the end of the
2512connection (or when you no longer want to use it) you can call the
2513C<destroy> method.
2514
2515=item How do I read data until the other side closes the connection?
2516
2517If you just want to read your data into a perl scalar, the easiest way
2518to achieve this is by setting an C<on_read> callback that does nothing,
2519clearing the C<on_eof> callback and in the C<on_error> callback, the data
2520will be in C<$_[0]{rbuf}>:
2521
2522 $handle->on_read (sub { });
2523 $handle->on_eof (undef);
2524 $handle->on_error (sub {
2525 my $data = delete $_[0]{rbuf};
2526 });
2527
2528Note that this example removes the C<rbuf> member from the handle object,
2529which is not normally allowed by the API. It is expressly permitted in
2530this case only, as the handle object needs to be destroyed afterwards.
2531
2532The reason to use C<on_error> is that TCP connections, due to latencies
2533and packets loss, might get closed quite violently with an error, when in
2534fact all data has been received.
2535
2536It is usually better to use acknowledgements when transferring data,
2537to make sure the other side hasn't just died and you got the data
2538intact. This is also one reason why so many internet protocols have an
2539explicit QUIT command.
2540
2541=item I don't want to destroy the handle too early - how do I wait until
2542all data has been written?
2543
2544After writing your last bits of data, set the C<on_drain> callback
2545and destroy the handle in there - with the default setting of
2546C<low_water_mark> this will be called precisely when all data has been
2547written to the socket:
2548
2549 $handle->push_write (...);
2550 $handle->on_drain (sub {
2551 AE::log debug => "All data submitted to the kernel.";
2552 undef $handle;
2553 });
2554
2555If you just want to queue some data and then signal EOF to the other side,
2556consider using C<< ->push_shutdown >> instead.
2557
2558=item I want to contact a TLS/SSL server, I don't care about security.
2559
2560If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2561connect to it and then create the AnyEvent::Handle with the C<tls>
2562parameter:
2563
2564 tcp_connect $host, $port, sub {
2565 my ($fh) = @_;
2566
2567 my $handle = new AnyEvent::Handle
2568 fh => $fh,
2569 tls => "connect",
2570 on_error => sub { ... };
2571
2572 $handle->push_write (...);
1129 } 2573 };
1130} 2574
2575=item I want to contact a TLS/SSL server, I do care about security.
2576
2577Then you should additionally enable certificate verification, including
2578peername verification, if the protocol you use supports it (see
2579L<AnyEvent::TLS>, C<verify_peername>).
2580
2581E.g. for HTTPS:
2582
2583 tcp_connect $host, $port, sub {
2584 my ($fh) = @_;
2585
2586 my $handle = new AnyEvent::Handle
2587 fh => $fh,
2588 peername => $host,
2589 tls => "connect",
2590 tls_ctx => { verify => 1, verify_peername => "https" },
2591 ...
2592
2593Note that you must specify the hostname you connected to (or whatever
2594"peername" the protocol needs) as the C<peername> argument, otherwise no
2595peername verification will be done.
2596
2597The above will use the system-dependent default set of trusted CA
2598certificates. If you want to check against a specific CA, add the
2599C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
2600
2601 tls_ctx => {
2602 verify => 1,
2603 verify_peername => "https",
2604 ca_file => "my-ca-cert.pem",
2605 },
2606
2607=item I want to create a TLS/SSL server, how do I do that?
2608
2609Well, you first need to get a server certificate and key. You have
2610three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
2611self-signed certificate (cheap. check the search engine of your choice,
2612there are many tutorials on the net) or c) make your own CA (tinyca2 is a
2613nice program for that purpose).
2614
2615Then create a file with your private key (in PEM format, see
2616L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
2617file should then look like this:
2618
2619 -----BEGIN RSA PRIVATE KEY-----
2620 ...header data
2621 ... lots of base64'y-stuff
2622 -----END RSA PRIVATE KEY-----
2623
2624 -----BEGIN CERTIFICATE-----
2625 ... lots of base64'y-stuff
2626 -----END CERTIFICATE-----
2627
2628The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
2629specify this file as C<cert_file>:
2630
2631 tcp_server undef, $port, sub {
2632 my ($fh) = @_;
2633
2634 my $handle = new AnyEvent::Handle
2635 fh => $fh,
2636 tls => "accept",
2637 tls_ctx => { cert_file => "my-server-keycert.pem" },
2638 ...
2639
2640When you have intermediate CA certificates that your clients might not
2641know about, just append them to the C<cert_file>.
1131 2642
1132=back 2643=back
1133 2644
1134=head1 SUBCLASSING AnyEvent::Handle 2645=head1 SUBCLASSING AnyEvent::Handle
1135 2646
1141=over 4 2652=over 4
1142 2653
1143=item * all constructor arguments become object members. 2654=item * all constructor arguments become object members.
1144 2655
1145At least initially, when you pass a C<tls>-argument to the constructor it 2656At 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 2657will 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). 2658mutated later on (for example C<tls> will hold the TLS connection object).
1148 2659
1149=item * other object member names are prefixed with an C<_>. 2660=item * other object member names are prefixed with an C<_>.
1150 2661
1151All object members not explicitly documented (internal use) are prefixed 2662All object members not explicitly documented (internal use) are prefixed
1154 2665
1155=item * all members not documented here and not prefixed with an underscore 2666=item * all members not documented here and not prefixed with an underscore
1156are free to use in subclasses. 2667are free to use in subclasses.
1157 2668
1158Of course, new versions of AnyEvent::Handle may introduce more "public" 2669Of course, new versions of AnyEvent::Handle may introduce more "public"
1159member variables, but thats just life, at least it is documented. 2670member variables, but that's just life. At least it is documented.
1160 2671
1161=back 2672=back
1162 2673
1163=head1 AUTHOR 2674=head1 AUTHOR
1164 2675
1165Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2676Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1166 2677
1167=cut 2678=cut
1168 2679
11691; # End of AnyEvent::Handle 26801
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