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Revision 1.79 by root, Sun Jul 27 08:37:56 2008 UTC vs.
Revision 1.236 by root, Sat May 12 23:14:29 2012 UTC

1package AnyEvent::Handle;
2
3no warnings;
4use strict qw(subs vars);
5
6use AnyEvent ();
7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util ();
9use Carp ();
10use Fcntl ();
11use Errno qw(EAGAIN EINTR);
12
13=head1 NAME 1=head1 NAME
14 2
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17=cut
18
19our $VERSION = 4.22;
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 => $filehandle [C<fh> or C<connect> MANDATORY]
72 93
73The filehandle this L<AnyEvent::Handle> object will operate on. 94The filehandle this L<AnyEvent::Handle> object will operate on.
74
75NOTE: The filehandle will be set to non-blocking (using 95NOTE: The filehandle will be set to non-blocking mode (using
76AnyEvent::Util::fh_nonblocking). 96C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
97that mode.
77 98
99=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
100
101Try to connect to the specified host and service (port), using
102C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
103default C<peername>.
104
105You have to specify either this parameter, or C<fh>, above.
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
78=item on_eof => $cb->($handle) 116=item on_prepare => $cb->($handle)
79 117
80Set the callback to be called when an end-of-file condition is detected, 118This (rarely used) callback is called before a new connection is
81i.e. in the case of a socket, when the other side has closed the 119attempted, but after the file handle has been created (you can access that
82connection cleanly. 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).
83 123
84While not mandatory, it is highly recommended to set an eof callback, 124The return value of this callback should be the connect timeout value in
85otherwise you might end up with a closed socket while you are still 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
86waiting for data. 126default timeout is to be used).
87 127
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
88=item on_error => $cb->($handle, $fatal) 160=item on_error => $cb->($handle, $fatal, $message)
89 161
90This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
91occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
92connect or a read error. 164connect, or a read error.
93 165
94Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
95fatal errors the handle object will be shut down and will not be 167fatal errors the handle object will be destroyed (by a call to C<< ->
168destroy >>) after invoking the error callback (which means you are free to
169examine the handle object). Examples of fatal errors are an EOF condition
170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well.
176
177If you report the error to the user, it is recommended to always output
178the C<$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
96usable. Non-fatal errors can be retried by simply returning, but it is 185Non-fatal errors can be retried by returning, but it is recommended
97recommended to simply ignore this parameter and instead abondon the handle 186to simply ignore this parameter and instead abondon the handle object
98object when this callback is invoked. 187when this callback is invoked. Examples of non-fatal errors are timeouts
188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99 189
100On callback entrance, the value of C<$!> contains the operating system 190On entry to the callback, the value of C<$!> contains the operating
101error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). 191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
192C<EPROTO>).
102 193
103While 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
104you will not be notified of errors otherwise. The default simply calls 195you will not be notified of errors otherwise. The default just calls
105C<croak>. 196C<croak>.
106 197
107=item on_read => $cb->($handle) 198=item on_read => $cb->($handle)
108 199
109This sets the default read callback, which is called when data arrives 200This sets the default read callback, which is called when data arrives
110and no read request is in the queue (unlike read queue callbacks, this 201and no read request is in the queue (unlike read queue callbacks, this
111callback will only be called when at least one octet of data is in the 202callback will only be called when at least one octet of data is in the
112read buffer). 203read buffer).
113 204
114To 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 >>
115method or access the C<$handle->{rbuf}> member directly. 206method or access the C<< $handle->{rbuf} >> member directly. Note that you
207must not enlarge or modify the read buffer, you can only remove data at
208the beginning from it.
116 209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
117When an EOF condition is detected then AnyEvent::Handle will first try to 213When an EOF condition is detected, AnyEvent::Handle will first try to
118feed all the remaining data to the queued callbacks and C<on_read> before 214feed all the remaining data to the queued callbacks and C<on_read> before
119calling the C<on_eof> callback. If no progress can be made, then a fatal 215calling the C<on_eof> callback. If no progress can be made, then a fatal
120error will be raised (with C<$!> set to C<EPIPE>). 216error will be raised (with C<$!> set to C<EPIPE>).
121 217
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
122=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
123 240
124This 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
125(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
126 243
127To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
128 245
129This callback is useful when you don't want to put all of your write data 246This callback is useful when you don't want to put all of your write data
130into the queue at once, for example, when you want to write the contents 247into the queue at once, for example, when you want to write the contents
132memory and push it into the queue, but instead only read more data from 249memory and push it into the queue, but instead only read more data from
133the file when the write queue becomes empty. 250the file when the write queue becomes empty.
134 251
135=item timeout => $fractional_seconds 252=item timeout => $fractional_seconds
136 253
254=item rtimeout => $fractional_seconds
255
256=item wtimeout => $fractional_seconds
257
137If non-zero, then this enables an "inactivity" timeout: whenever this many 258If non-zero, then these enables an "inactivity" timeout: whenever this
138seconds pass without a successful read or write on the underlying file 259many seconds pass without a successful read or write on the underlying
139handle, the C<on_timeout> callback will be invoked (and if that one is 260file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
140missing, an C<ETIMEDOUT> error will be raised). 261will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
262error will be raised).
141 263
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
142Note that timeout processing is also active when you currently do not have 271Note that timeout processing is active even when you do not have any
143any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
144idle then you should disable the timout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
145in the C<on_timeout> callback. 274timeout in the corresponding C<on_timeout> callback, in which case
275AnyEvent::Handle will simply restart the timeout.
146 276
147Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
148 278
149=item on_timeout => $cb->($handle) 279=item on_timeout => $cb->($handle)
280
281=item on_rtimeout => $cb->($handle)
282
283=item on_wtimeout => $cb->($handle)
150 284
151Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
152callback, then the timeout will be reset as if some activity had happened, 286callback, then the timeout will be reset as if some activity had happened,
153so this condition is not fatal in any way. 287so this condition is not fatal in any way.
154 288
155=item rbuf_max => <bytes> 289=item rbuf_max => <bytes>
156 290
157If 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>)
158when 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
159avoid denial-of-service attacks. 293avoid some forms of denial-of-service attacks.
160 294
161For example, a server accepting connections from untrusted sources should 295For example, a server accepting connections from untrusted sources should
162be 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
163(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
164amount 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
165isn't finished). 299isn't finished).
166 300
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
167=item autocork => <boolean> 316=item autocork => <boolean>
168 317
169When disabled (the default), then C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
170write the data to the handle if possible. This avoids having to register 319write the data to the handle if possible. This avoids having to register
171a write watcher and wait for the next event loop iteration, but can be 320a write watcher and wait for the next event loop iteration, but can
172inefficient if you write multiple small chunks (this disadvantage is 321be inefficient if you write multiple small chunks (on the wire, this
173usually avoided by your kernel's nagle algorithm, see C<low_delay>). 322disadvantage is usually avoided by your kernel's nagle algorithm, see
323C<no_delay>, but this option can save costly syscalls).
174 324
175When enabled, then writes will always be queued till the next event loop 325When enabled, writes will always be queued till the next event loop
176iteration. This is efficient when you do many small writes per iteration, 326iteration. This is efficient when you do many small writes per iteration,
177but less efficient when you do a single write only. 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.
178 329
179=item no_delay => <boolean> 330=item no_delay => <boolean>
180 331
181When doing small writes on sockets, your operating system kernel might 332When doing small writes on sockets, your operating system kernel might
182wait a bit for more data before actually sending it out. This is called 333wait a bit for more data before actually sending it out. This is called
183the Nagle algorithm, and usually it is beneficial. 334the Nagle algorithm, and usually it is beneficial.
184 335
185In some situations you want as low a delay as possible, which cna be 336In some situations you want as low a delay as possible, which can be
186accomplishd by setting this option to true. 337accomplishd by setting this option to a true value.
187 338
188The default is your opertaing system's default behaviour, this option 339The default is your operating system's default behaviour (most likely
189explicitly enables or disables it, if possible. 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.
190 373
191=item read_size => <bytes> 374=item read_size => <bytes>
192 375
193The 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
194during each (loop iteration). Default: C<8192>. 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.
195 388
196=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
197 390
198Sets 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
199buffer: 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
200considered empty. 393considered empty.
201 394
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
202=item linger => <seconds> 400=item linger => <seconds>
203 401
204If non-zero (default: C<3600>), then the destructor of the 402If this is non-zero (default: C<3600>), the destructor of the
205AnyEvent::Handle object will check wether there is still outstanding write 403AnyEvent::Handle object will check whether there is still outstanding
206data and will install a watcher that will write out this data. No errors 404write data and will install a watcher that will write this data to the
207will be reported (this mostly matches how the operating system treats 405socket. No errors will be reported (this mostly matches how the operating
208outstanding data at socket close time). 406system treats outstanding data at socket close time).
209 407
210This will not work for partial TLS data that could not yet been 408This will not work for partial TLS data that could not be encoded
211encoded. This data will be lost. 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>.
212 421
213=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
214 423
215When this parameter is given, it enables TLS (SSL) mode, that means it 424When this parameter is given, it enables TLS (SSL) mode, that means
216will start making tls handshake and will transparently encrypt/decrypt 425AnyEvent will start a TLS handshake as soon as the connection has been
217data. 426established and will transparently encrypt/decrypt data afterwards.
427
428All TLS protocol errors will be signalled as C<EPROTO>, with an
429appropriate error message.
218 430
219TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
220automatically 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.
221 436
222For 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
223connection, use C<connect> mode. 438C<accept>, and for the TLS client side of a connection, use C<connect>
439mode.
224 440
225You can also provide your own TLS connection object, but you have 441You can also provide your own TLS connection object, but you have
226to 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>
227or 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
228AnyEvent::Handle. 444AnyEvent::Handle. Also, this module will take ownership of this connection
445object.
229 446
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
230See 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.
231 457
232=item tls_ctx => $ssl_ctx 458=item tls_ctx => $anyevent_tls
233 459
234Use 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
235(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
236missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 462parameter is missing (or C<undef>), then AnyEvent::Handle will use
463C<AnyEvent::Handle::TLS_CTX>.
464
465Instead of an object, you can also specify a hash reference with C<< key
466=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
467new TLS context object.
468
469=item on_starttls => $cb->($handle, $success[, $error_message])
470
471This callback will be invoked when the TLS/SSL handshake has finished. If
472C<$success> is true, then the TLS handshake succeeded, otherwise it failed
473(C<on_stoptls> will not be called in this case).
474
475The session in C<< $handle->{tls} >> can still be examined in this
476callback, even when the handshake was not successful.
477
478TLS handshake failures will not cause C<on_error> to be invoked when this
479callback is in effect, instead, the error message will be passed to C<on_starttls>.
480
481Without this callback, handshake failures lead to C<on_error> being
482called as usual.
483
484Note that you cannot just call C<starttls> again in this callback. If you
485need to do that, start an zero-second timer instead whose callback can
486then call C<< ->starttls >> again.
487
488=item on_stoptls => $cb->($handle)
489
490When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
491set, then it will be invoked after freeing the TLS session. If it is not,
492then a TLS shutdown condition will be treated like a normal EOF condition
493on the handle.
494
495The session in C<< $handle->{tls} >> can still be examined in this
496callback.
497
498This callback will only be called on TLS shutdowns, not when the
499underlying handle signals EOF.
237 500
238=item json => JSON or JSON::XS object 501=item json => JSON or JSON::XS object
239 502
240This 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.
241 504
242If 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
243suitable one, which will write and expect UTF-8 encoded JSON texts. 506suitable one (on demand), which will write and expect UTF-8 encoded JSON
507texts.
244 508
245Note that you are responsible to depend on the JSON module if you want to 509Note that you are responsible to depend on the JSON module if you want to
246use this functionality, as AnyEvent does not have a dependency itself. 510use this functionality, as AnyEvent does not have a dependency itself.
247 511
248=item filter_r => $cb
249
250=item filter_w => $cb
251
252These exist, but are undocumented at this time.
253
254=back 512=back
255 513
256=cut 514=cut
257 515
258sub new { 516sub new {
259 my $class = shift; 517 my $class = shift;
260
261 my $self = bless { @_ }, $class; 518 my $self = bless { @_ }, $class;
262 519
263 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 520 if ($self->{fh}) {
521 $self->_start;
522 return unless $self->{fh}; # could be gone by now
523
524 } elsif ($self->{connect}) {
525 require AnyEvent::Socket;
526
527 $self->{peername} = $self->{connect}[0]
528 unless exists $self->{peername};
529
530 $self->{_skip_drain_rbuf} = 1;
531
532 {
533 Scalar::Util::weaken (my $self = $self);
534
535 $self->{_connect} =
536 AnyEvent::Socket::tcp_connect (
537 $self->{connect}[0],
538 $self->{connect}[1],
539 sub {
540 my ($fh, $host, $port, $retry) = @_;
541
542 delete $self->{_connect}; # no longer needed
543
544 if ($fh) {
545 $self->{fh} = $fh;
546
547 delete $self->{_skip_drain_rbuf};
548 $self->_start;
549
550 $self->{on_connect}
551 and $self->{on_connect}($self, $host, $port, sub {
552 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
553 $self->{_skip_drain_rbuf} = 1;
554 &$retry;
555 });
556
557 } else {
558 if ($self->{on_connect_error}) {
559 $self->{on_connect_error}($self, "$!");
560 $self->destroy if $self;
561 } else {
562 $self->_error ($!, 1);
563 }
564 }
565 },
566 sub {
567 local $self->{fh} = $_[0];
568
569 $self->{on_prepare}
570 ? $self->{on_prepare}->($self)
571 : ()
572 }
573 );
574 }
575
576 } else {
577 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
578 }
579
580 $self
581}
582
583sub _start {
584 my ($self) = @_;
585
586 # too many clueless people try to use udp and similar sockets
587 # with AnyEvent::Handle, do them a favour.
588 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
589 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
590 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
264 591
265 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 592 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
266 593
267 if ($self->{tls}) { 594 $self->{_activity} =
268 require Net::SSLeay; 595 $self->{_ractivity} =
596 $self->{_wactivity} = AE::now;
597
598 $self->{read_size} ||= 2048;
599 $self->{max_read_size} = $self->{read_size}
600 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
601
602 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
603 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
604 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
605
606 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
607 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
608
609 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
610
269 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 611 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
270 } 612 if $self->{tls};
271 613
272 $self->{_activity} = AnyEvent->now;
273 $self->_timeout;
274
275 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 614 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
276 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
277 615
278 $self->start_read 616 $self->start_read
279 if $self->{on_read}; 617 if $self->{on_read} || @{ $self->{_queue} };
280 618
281 $self 619 $self->_drain_wbuf;
282}
283
284sub _shutdown {
285 my ($self) = @_;
286
287 delete $self->{_tw};
288 delete $self->{_rw};
289 delete $self->{_ww};
290 delete $self->{fh};
291
292 $self->stoptls;
293} 620}
294 621
295sub _error { 622sub _error {
296 my ($self, $errno, $fatal) = @_; 623 my ($self, $errno, $fatal, $message) = @_;
297
298 $self->_shutdown
299 if $fatal;
300 624
301 $! = $errno; 625 $! = $errno;
626 $message ||= "$!";
302 627
303 if ($self->{on_error}) { 628 if ($self->{on_error}) {
304 $self->{on_error}($self, $fatal); 629 $self->{on_error}($self, $fatal, $message);
305 } else { 630 $self->destroy if $fatal;
631 } elsif ($self->{fh} || $self->{connect}) {
632 $self->destroy;
306 Carp::croak "AnyEvent::Handle uncaught error: $!"; 633 Carp::croak "AnyEvent::Handle uncaught error: $message";
307 } 634 }
308} 635}
309 636
310=item $fh = $handle->fh 637=item $fh = $handle->fh
311 638
312This method returns the file handle of the L<AnyEvent::Handle> object. 639This method returns the file handle used to create the L<AnyEvent::Handle> object.
313 640
314=cut 641=cut
315 642
316sub fh { $_[0]{fh} } 643sub fh { $_[0]{fh} }
317 644
335 $_[0]{on_eof} = $_[1]; 662 $_[0]{on_eof} = $_[1];
336} 663}
337 664
338=item $handle->on_timeout ($cb) 665=item $handle->on_timeout ($cb)
339 666
340Replace the current C<on_timeout> callback, or disables the callback 667=item $handle->on_rtimeout ($cb)
341(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
342argument.
343 668
344=cut 669=item $handle->on_wtimeout ($cb)
345 670
346sub on_timeout { 671Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
347 $_[0]{on_timeout} = $_[1]; 672callback, or disables the callback (but not the timeout) if C<$cb> =
348} 673C<undef>. See the C<timeout> constructor argument and method.
674
675=cut
676
677# see below
349 678
350=item $handle->autocork ($boolean) 679=item $handle->autocork ($boolean)
351 680
352Enables or disables the current autocork behaviour (see C<autocork> 681Enables or disables the current autocork behaviour (see C<autocork>
353constructor argument). 682constructor argument). Changes will only take effect on the next write.
354 683
355=cut 684=cut
685
686sub autocork {
687 $_[0]{autocork} = $_[1];
688}
356 689
357=item $handle->no_delay ($boolean) 690=item $handle->no_delay ($boolean)
358 691
359Enables or disables the C<no_delay> setting (see constructor argument of 692Enables or disables the C<no_delay> setting (see constructor argument of
360the same name for details). 693the same name for details).
362=cut 695=cut
363 696
364sub no_delay { 697sub no_delay {
365 $_[0]{no_delay} = $_[1]; 698 $_[0]{no_delay} = $_[1];
366 699
700 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
701 if $_[0]{fh};
702}
703
704=item $handle->keepalive ($boolean)
705
706Enables or disables the C<keepalive> setting (see constructor argument of
707the same name for details).
708
709=cut
710
711sub keepalive {
712 $_[0]{keepalive} = $_[1];
713
367 eval { 714 eval {
368 local $SIG{__DIE__}; 715 local $SIG{__DIE__};
369 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]; 716 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
717 if $_[0]{fh};
370 }; 718 };
371} 719}
372 720
721=item $handle->oobinline ($boolean)
722
723Enables or disables the C<oobinline> setting (see constructor argument of
724the same name for details).
725
726=cut
727
728sub oobinline {
729 $_[0]{oobinline} = $_[1];
730
731 eval {
732 local $SIG{__DIE__};
733 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
734 if $_[0]{fh};
735 };
736}
737
738=item $handle->keepalive ($boolean)
739
740Enables or disables the C<keepalive> setting (see constructor argument of
741the same name for details).
742
743=cut
744
745sub keepalive {
746 $_[0]{keepalive} = $_[1];
747
748 eval {
749 local $SIG{__DIE__};
750 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
751 if $_[0]{fh};
752 };
753}
754
755=item $handle->on_starttls ($cb)
756
757Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
758
759=cut
760
761sub on_starttls {
762 $_[0]{on_starttls} = $_[1];
763}
764
765=item $handle->on_stoptls ($cb)
766
767Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
768
769=cut
770
771sub on_stoptls {
772 $_[0]{on_stoptls} = $_[1];
773}
774
775=item $handle->rbuf_max ($max_octets)
776
777Configures the C<rbuf_max> setting (C<undef> disables it).
778
779=item $handle->wbuf_max ($max_octets)
780
781Configures the C<wbuf_max> setting (C<undef> disables it).
782
783=cut
784
785sub rbuf_max {
786 $_[0]{rbuf_max} = $_[1];
787}
788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
373############################################################################# 793#############################################################################
374 794
375=item $handle->timeout ($seconds) 795=item $handle->timeout ($seconds)
376 796
797=item $handle->rtimeout ($seconds)
798
799=item $handle->wtimeout ($seconds)
800
377Configures (or disables) the inactivity timeout. 801Configures (or disables) the inactivity timeout.
378 802
379=cut 803The timeout will be checked instantly, so this method might destroy the
804handle before it returns.
380 805
381sub timeout { 806=item $handle->timeout_reset
807
808=item $handle->rtimeout_reset
809
810=item $handle->wtimeout_reset
811
812Reset the activity timeout, as if data was received or sent.
813
814These methods are cheap to call.
815
816=cut
817
818for my $dir ("", "r", "w") {
819 my $timeout = "${dir}timeout";
820 my $tw = "_${dir}tw";
821 my $on_timeout = "on_${dir}timeout";
822 my $activity = "_${dir}activity";
823 my $cb;
824
825 *$on_timeout = sub {
826 $_[0]{$on_timeout} = $_[1];
827 };
828
829 *$timeout = sub {
382 my ($self, $timeout) = @_; 830 my ($self, $new_value) = @_;
383 831
832 $new_value >= 0
833 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
834
384 $self->{timeout} = $timeout; 835 $self->{$timeout} = $new_value;
385 $self->_timeout; 836 delete $self->{$tw}; &$cb;
386} 837 };
387 838
839 *{"${dir}timeout_reset"} = sub {
840 $_[0]{$activity} = AE::now;
841 };
842
843 # main workhorse:
388# reset the timeout watcher, as neccessary 844 # reset the timeout watcher, as neccessary
389# also check for time-outs 845 # also check for time-outs
390sub _timeout { 846 $cb = sub {
391 my ($self) = @_; 847 my ($self) = @_;
392 848
393 if ($self->{timeout}) { 849 if ($self->{$timeout} && $self->{fh}) {
394 my $NOW = AnyEvent->now; 850 my $NOW = AE::now;
395 851
396 # when would the timeout trigger? 852 # when would the timeout trigger?
397 my $after = $self->{_activity} + $self->{timeout} - $NOW; 853 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
398 854
399 # now or in the past already? 855 # now or in the past already?
400 if ($after <= 0) { 856 if ($after <= 0) {
401 $self->{_activity} = $NOW; 857 $self->{$activity} = $NOW;
402 858
403 if ($self->{on_timeout}) { 859 if ($self->{$on_timeout}) {
404 $self->{on_timeout}($self); 860 $self->{$on_timeout}($self);
405 } else { 861 } else {
406 $self->_error (&Errno::ETIMEDOUT); 862 $self->_error (Errno::ETIMEDOUT);
863 }
864
865 # callback could have changed timeout value, optimise
866 return unless $self->{$timeout};
867
868 # calculate new after
869 $after = $self->{$timeout};
407 } 870 }
408 871
409 # callback could have changed timeout value, optimise 872 Scalar::Util::weaken $self;
410 return unless $self->{timeout}; 873 return unless $self; # ->error could have destroyed $self
411 874
412 # calculate new after 875 $self->{$tw} ||= AE::timer $after, 0, sub {
413 $after = $self->{timeout}; 876 delete $self->{$tw};
877 $cb->($self);
878 };
879 } else {
880 delete $self->{$tw};
414 } 881 }
415
416 Scalar::Util::weaken $self;
417 return unless $self; # ->error could have destroyed $self
418
419 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
420 delete $self->{_tw};
421 $self->_timeout;
422 });
423 } else {
424 delete $self->{_tw};
425 } 882 }
426} 883}
427 884
428############################################################################# 885#############################################################################
429 886
436 893
437The write queue is very simple: you can add data to its end, and 894The write queue is very simple: you can add data to its end, and
438AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
439 896
440When data could be written and the write buffer is shorter then the low 897When data could be written and the write buffer is shorter then the low
441water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
442 899
443=over 4 900=over 4
444 901
445=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
446 903
447Sets the C<on_drain> callback or clears it (see the description of 904Sets the C<on_drain> callback or clears it (see the description of
448C<on_drain> in the constructor). 905C<on_drain> in the constructor).
449 906
907This method may invoke callbacks (and therefore the handle might be
908destroyed after it returns).
909
450=cut 910=cut
451 911
452sub on_drain { 912sub on_drain {
453 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
454 914
455 $self->{on_drain} = $cb; 915 $self->{on_drain} = $cb;
456 916
457 $cb->($self) 917 $cb->($self)
458 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 918 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
459} 919}
460 920
461=item $handle->push_write ($data) 921=item $handle->push_write ($data)
462 922
463Queues the given scalar to be written. You can push as much data as you 923Queues the given scalar to be written. You can push as much data as
464want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
465buffers it independently of the kernel. 925C<AnyEvent::Handle> buffers it independently of the kernel.
926
927This method may invoke callbacks (and therefore the handle might be
928destroyed after it returns).
466 929
467=cut 930=cut
468 931
469sub _drain_wbuf { 932sub _drain_wbuf {
470 my ($self) = @_; 933 my ($self) = @_;
474 Scalar::Util::weaken $self; 937 Scalar::Util::weaken $self;
475 938
476 my $cb = sub { 939 my $cb = sub {
477 my $len = syswrite $self->{fh}, $self->{wbuf}; 940 my $len = syswrite $self->{fh}, $self->{wbuf};
478 941
479 if ($len >= 0) { 942 if (defined $len) {
480 substr $self->{wbuf}, 0, $len, ""; 943 substr $self->{wbuf}, 0, $len, "";
481 944
482 $self->{_activity} = AnyEvent->now; 945 $self->{_activity} = $self->{_wactivity} = AE::now;
483 946
484 $self->{on_drain}($self) 947 $self->{on_drain}($self)
485 if $self->{low_water_mark} >= length $self->{wbuf} 948 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
486 && $self->{on_drain}; 949 && $self->{on_drain};
487 950
488 delete $self->{_ww} unless length $self->{wbuf}; 951 delete $self->{_ww} unless length $self->{wbuf};
489 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 952 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
490 $self->_error ($!, 1); 953 $self->_error ($!, 1);
493 956
494 # try to write data immediately 957 # try to write data immediately
495 $cb->() unless $self->{autocork}; 958 $cb->() unless $self->{autocork};
496 959
497 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
498 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
499 if length $self->{wbuf}; 962 if length $self->{wbuf};
963
964 if (
965 defined $self->{wbuf_max}
966 && $self->{wbuf_max} < length $self->{wbuf}
967 ) {
968 $self->_error (Errno::ENOSPC, 1), return;
969 }
500 }; 970 };
501} 971}
502 972
503our %WH; 973our %WH;
504 974
975# deprecated
505sub register_write_type($$) { 976sub register_write_type($$) {
506 $WH{$_[0]} = $_[1]; 977 $WH{$_[0]} = $_[1];
507} 978}
508 979
509sub push_write { 980sub push_write {
510 my $self = shift; 981 my $self = shift;
511 982
512 if (@_ > 1) { 983 if (@_ > 1) {
513 my $type = shift; 984 my $type = shift;
514 985
986 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
515 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 987 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
516 ->($self, @_); 988 ->($self, @_);
517 } 989 }
518 990
991 # we downgrade here to avoid hard-to-track-down bugs,
992 # and diagnose the problem earlier and better.
993
519 if ($self->{filter_w}) { 994 if ($self->{tls}) {
520 $self->{filter_w}($self, \$_[0]); 995 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
996 &_dotls ($self) if $self->{fh};
521 } else { 997 } else {
522 $self->{wbuf} .= $_[0]; 998 utf8::downgrade $self->{wbuf} .= $_[0];
523 $self->_drain_wbuf; 999 $self->_drain_wbuf if $self->{fh};
524 } 1000 }
525} 1001}
526 1002
527=item $handle->push_write (type => @args) 1003=item $handle->push_write (type => @args)
528 1004
529Instead of formatting your data yourself, you can also let this module do 1005Instead of formatting your data yourself, you can also let this module
530the job by specifying a type and type-specific arguments. 1006do the job by specifying a type and type-specific arguments. You
1007can also specify the (fully qualified) name of a package, in which
1008case AnyEvent tries to load the package and then expects to find the
1009C<anyevent_write_type> function inside (see "custom write types", below).
531 1010
532Predefined types are (if you have ideas for additional types, feel free to 1011Predefined types are (if you have ideas for additional types, feel free to
533drop by and tell us): 1012drop by and tell us):
534 1013
535=over 4 1014=over 4
542=cut 1021=cut
543 1022
544register_write_type netstring => sub { 1023register_write_type netstring => sub {
545 my ($self, $string) = @_; 1024 my ($self, $string) = @_;
546 1025
547 sprintf "%d:%s,", (length $string), $string 1026 (length $string) . ":$string,"
548}; 1027};
549 1028
550=item packstring => $format, $data 1029=item packstring => $format, $data
551 1030
552An octet string prefixed with an encoded length. The encoding C<$format> 1031An octet string prefixed with an encoded length. The encoding C<$format>
592Other languages could read single lines terminated by a newline and pass 1071Other languages could read single lines terminated by a newline and pass
593this line into their JSON decoder of choice. 1072this line into their JSON decoder of choice.
594 1073
595=cut 1074=cut
596 1075
1076sub json_coder() {
1077 eval { require JSON::XS; JSON::XS->new->utf8 }
1078 || do { require JSON; JSON->new->utf8 }
1079}
1080
597register_write_type json => sub { 1081register_write_type json => sub {
598 my ($self, $ref) = @_; 1082 my ($self, $ref) = @_;
599 1083
600 require JSON; 1084 my $json = $self->{json} ||= json_coder;
601 1085
602 $self->{json} ? $self->{json}->encode ($ref) 1086 $json->encode ($ref)
603 : JSON::encode_json ($ref)
604}; 1087};
605 1088
606=item storable => $reference 1089=item storable => $reference
607 1090
608Freezes the given reference using L<Storable> and writes it to the 1091Freezes the given reference using L<Storable> and writes it to the
611=cut 1094=cut
612 1095
613register_write_type storable => sub { 1096register_write_type storable => sub {
614 my ($self, $ref) = @_; 1097 my ($self, $ref) = @_;
615 1098
616 require Storable; 1099 require Storable unless $Storable::VERSION;
617 1100
618 pack "w/a*", Storable::nfreeze ($ref) 1101 pack "w/a*", Storable::nfreeze ($ref)
619}; 1102};
620 1103
621=back 1104=back
622 1105
623=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1106=item $handle->push_shutdown
624 1107
625This function (not method) lets you add your own types to C<push_write>. 1108Sometimes you know you want to close the socket after writing your data
1109before it was actually written. One way to do that is to replace your
1110C<on_drain> handler by a callback that shuts down the socket (and set
1111C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1112replaces the C<on_drain> callback with:
1113
1114 sub { shutdown $_[0]{fh}, 1 }
1115
1116This simply shuts down the write side and signals an EOF condition to the
1117the peer.
1118
1119You can rely on the normal read queue and C<on_eof> handling
1120afterwards. This is the cleanest way to close a connection.
1121
1122This method may invoke callbacks (and therefore the handle might be
1123destroyed after it returns).
1124
1125=cut
1126
1127sub push_shutdown {
1128 my ($self) = @_;
1129
1130 delete $self->{low_water_mark};
1131 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1132}
1133
1134=item custom write types - Package::anyevent_write_type $handle, @args
1135
1136Instead of one of the predefined types, you can also specify the name of
1137a package. AnyEvent will try to load the package and then expects to find
1138a function named C<anyevent_write_type> inside. If it isn't found, it
1139progressively tries to load the parent package until it either finds the
1140function (good) or runs out of packages (bad).
1141
626Whenever the given C<type> is used, C<push_write> will invoke the code 1142Whenever the given C<type> is used, C<push_write> will the function with
627reference with the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
628 1144
629The code reference is supposed to return a single octet string that will 1145The function is supposed to return a single octet string that will be
630be appended to the write buffer. 1146appended to the write buffer, so you can mentally treat this function as a
1147"arguments to on-the-wire-format" converter.
631 1148
632Note that this is a function, and all types registered this way will be 1149Example: implement a custom write type C<join> that joins the remaining
633global, so try to use unique names. 1150arguments using the first one.
1151
1152 $handle->push_write (My::Type => " ", 1,2,3);
1153
1154 # uses the following package, which can be defined in the "My::Type" or in
1155 # the "My" modules to be auto-loaded, or just about anywhere when the
1156 # My::Type::anyevent_write_type is defined before invoking it.
1157
1158 package My::Type;
1159
1160 sub anyevent_write_type {
1161 my ($handle, $delim, @args) = @_;
1162
1163 join $delim, @args
1164 }
634 1165
635=cut 1166=cut
636 1167
637############################################################################# 1168#############################################################################
638 1169
647ways, the "simple" way, using only C<on_read> and the "complex" way, using 1178ways, the "simple" way, using only C<on_read> and the "complex" way, using
648a queue. 1179a queue.
649 1180
650In the simple case, you just install an C<on_read> callback and whenever 1181In the simple case, you just install an C<on_read> callback and whenever
651new data arrives, it will be called. You can then remove some data (if 1182new data arrives, it will be called. You can then remove some data (if
652enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1183enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
653leave the data there if you want to accumulate more (e.g. when only a 1184leave the data there if you want to accumulate more (e.g. when only a
654partial message has been received so far). 1185partial message has been received so far), or change the read queue with
1186e.g. C<push_read>.
655 1187
656In the more complex case, you want to queue multiple callbacks. In this 1188In the more complex case, you want to queue multiple callbacks. In this
657case, AnyEvent::Handle will call the first queued callback each time new 1189case, AnyEvent::Handle will call the first queued callback each time new
658data arrives (also the first time it is queued) and removes it when it has 1190data arrives (also the first time it is queued) and remove it when it has
659done its job (see C<push_read>, below). 1191done its job (see C<push_read>, below).
660 1192
661This way you can, for example, push three line-reads, followed by reading 1193This way you can, for example, push three line-reads, followed by reading
662a chunk of data, and AnyEvent::Handle will execute them in order. 1194a chunk of data, and AnyEvent::Handle will execute them in order.
663 1195
720=cut 1252=cut
721 1253
722sub _drain_rbuf { 1254sub _drain_rbuf {
723 my ($self) = @_; 1255 my ($self) = @_;
724 1256
1257 # avoid recursion
1258 return if $self->{_skip_drain_rbuf};
725 local $self->{_in_drain} = 1; 1259 local $self->{_skip_drain_rbuf} = 1;
726
727 if (
728 defined $self->{rbuf_max}
729 && $self->{rbuf_max} < length $self->{rbuf}
730 ) {
731 return $self->_error (&Errno::ENOSPC, 1);
732 }
733 1260
734 while () { 1261 while () {
1262 # we need to use a separate tls read buffer, as we must not receive data while
1263 # we are draining the buffer, and this can only happen with TLS.
1264 $self->{rbuf} .= delete $self->{_tls_rbuf}
1265 if exists $self->{_tls_rbuf};
1266
735 my $len = length $self->{rbuf}; 1267 my $len = length $self->{rbuf};
736 1268
737 if (my $cb = shift @{ $self->{_queue} }) { 1269 if (my $cb = shift @{ $self->{_queue} }) {
738 unless ($cb->($self)) { 1270 unless ($cb->($self)) {
739 if ($self->{_eof}) { 1271 # no progress can be made
740 # no progress can be made (not enough data and no data forthcoming) 1272 # (not enough data and no data forthcoming)
741 $self->_error (&Errno::EPIPE, 1), last; 1273 $self->_error (Errno::EPIPE, 1), return
742 } 1274 if $self->{_eof};
743 1275
744 unshift @{ $self->{_queue} }, $cb; 1276 unshift @{ $self->{_queue} }, $cb;
745 last; 1277 last;
746 } 1278 }
747 } elsif ($self->{on_read}) { 1279 } elsif ($self->{on_read}) {
754 && !@{ $self->{_queue} } # and the queue is still empty 1286 && !@{ $self->{_queue} } # and the queue is still empty
755 && $self->{on_read} # but we still have on_read 1287 && $self->{on_read} # but we still have on_read
756 ) { 1288 ) {
757 # no further data will arrive 1289 # no further data will arrive
758 # so no progress can be made 1290 # so no progress can be made
759 $self->_error (&Errno::EPIPE, 1), last 1291 $self->_error (Errno::EPIPE, 1), return
760 if $self->{_eof}; 1292 if $self->{_eof};
761 1293
762 last; # more data might arrive 1294 last; # more data might arrive
763 } 1295 }
764 } else { 1296 } else {
765 # read side becomes idle 1297 # read side becomes idle
766 delete $self->{_rw}; 1298 delete $self->{_rw} unless $self->{tls};
767 last; 1299 last;
768 } 1300 }
769 } 1301 }
770 1302
1303 if ($self->{_eof}) {
1304 $self->{on_eof}
771 $self->{on_eof}($self) 1305 ? $self->{on_eof}($self)
772 if $self->{_eof} && $self->{on_eof}; 1306 : $self->_error (0, 1, "Unexpected end-of-file");
1307
1308 return;
1309 }
1310
1311 if (
1312 defined $self->{rbuf_max}
1313 && $self->{rbuf_max} < length $self->{rbuf}
1314 ) {
1315 $self->_error (Errno::ENOSPC, 1), return;
1316 }
773 1317
774 # may need to restart read watcher 1318 # may need to restart read watcher
775 unless ($self->{_rw}) { 1319 unless ($self->{_rw}) {
776 $self->start_read 1320 $self->start_read
777 if $self->{on_read} || @{ $self->{_queue} }; 1321 if $self->{on_read} || @{ $self->{_queue} };
782 1326
783This replaces the currently set C<on_read> callback, or clears it (when 1327This replaces the currently set C<on_read> callback, or clears it (when
784the new callback is C<undef>). See the description of C<on_read> in the 1328the new callback is C<undef>). See the description of C<on_read> in the
785constructor. 1329constructor.
786 1330
1331This method may invoke callbacks (and therefore the handle might be
1332destroyed after it returns).
1333
787=cut 1334=cut
788 1335
789sub on_read { 1336sub on_read {
790 my ($self, $cb) = @_; 1337 my ($self, $cb) = @_;
791 1338
792 $self->{on_read} = $cb; 1339 $self->{on_read} = $cb;
793 $self->_drain_rbuf if $cb && !$self->{_in_drain}; 1340 $self->_drain_rbuf if $cb;
794} 1341}
795 1342
796=item $handle->rbuf 1343=item $handle->rbuf
797 1344
798Returns the read buffer (as a modifiable lvalue). 1345Returns the read buffer (as a modifiable lvalue). You can also access the
1346read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1347much faster, and no less clean).
799 1348
800You can access the read buffer directly as the C<< ->{rbuf} >> member, if 1349The only operation allowed on the read buffer (apart from looking at it)
801you want. 1350is removing data from its beginning. Otherwise modifying or appending to
1351it is not allowed and will lead to hard-to-track-down bugs.
802 1352
803NOTE: The read buffer should only be used or modified if the C<on_read>, 1353NOTE: The read buffer should only be used or modified in the C<on_read>
804C<push_read> or C<unshift_read> methods are used. The other read methods 1354callback or when C<push_read> or C<unshift_read> are used with a single
805automatically manage the read buffer. 1355callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1356will manage the read buffer on their own.
806 1357
807=cut 1358=cut
808 1359
809sub rbuf : lvalue { 1360sub rbuf : lvalue {
810 $_[0]{rbuf} 1361 $_[0]{rbuf}
827 1378
828If enough data was available, then the callback must remove all data it is 1379If enough data was available, then the callback must remove all data it is
829interested in (which can be none at all) and return a true value. After returning 1380interested in (which can be none at all) and return a true value. After returning
830true, it will be removed from the queue. 1381true, it will be removed from the queue.
831 1382
1383These methods may invoke callbacks (and therefore the handle might be
1384destroyed after it returns).
1385
832=cut 1386=cut
833 1387
834our %RH; 1388our %RH;
835 1389
836sub register_read_type($$) { 1390sub register_read_type($$) {
842 my $cb = pop; 1396 my $cb = pop;
843 1397
844 if (@_) { 1398 if (@_) {
845 my $type = shift; 1399 my $type = shift;
846 1400
1401 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
847 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1402 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
848 ->($self, $cb, @_); 1403 ->($self, $cb, @_);
849 } 1404 }
850 1405
851 push @{ $self->{_queue} }, $cb; 1406 push @{ $self->{_queue} }, $cb;
852 $self->_drain_rbuf unless $self->{_in_drain}; 1407 $self->_drain_rbuf;
853} 1408}
854 1409
855sub unshift_read { 1410sub unshift_read {
856 my $self = shift; 1411 my $self = shift;
857 my $cb = pop; 1412 my $cb = pop;
858 1413
859 if (@_) { 1414 if (@_) {
860 my $type = shift; 1415 my $type = shift;
861 1416
1417 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
862 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1418 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
863 ->($self, $cb, @_); 1419 ->($self, $cb, @_);
864 } 1420 }
865 1421
866
867 unshift @{ $self->{_queue} }, $cb; 1422 unshift @{ $self->{_queue} }, $cb;
868 $self->_drain_rbuf unless $self->{_in_drain}; 1423 $self->_drain_rbuf;
869} 1424}
870 1425
871=item $handle->push_read (type => @args, $cb) 1426=item $handle->push_read (type => @args, $cb)
872 1427
873=item $handle->unshift_read (type => @args, $cb) 1428=item $handle->unshift_read (type => @args, $cb)
874 1429
875Instead of providing a callback that parses the data itself you can chose 1430Instead of providing a callback that parses the data itself you can chose
876between a number of predefined parsing formats, for chunks of data, lines 1431between a number of predefined parsing formats, for chunks of data, lines
877etc. 1432etc. You can also specify the (fully qualified) name of a package, in
1433which case AnyEvent tries to load the package and then expects to find the
1434C<anyevent_read_type> function inside (see "custom read types", below).
878 1435
879Predefined types are (if you have ideas for additional types, feel free to 1436Predefined types are (if you have ideas for additional types, feel free to
880drop by and tell us): 1437drop by and tell us):
881 1438
882=over 4 1439=over 4
888data. 1445data.
889 1446
890Example: read 2 bytes. 1447Example: read 2 bytes.
891 1448
892 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
893 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
894 }); 1451 });
895 1452
896=cut 1453=cut
897 1454
898register_read_type chunk => sub { 1455register_read_type chunk => sub {
932 if (@_ < 3) { 1489 if (@_ < 3) {
933 # this is more than twice as fast as the generic code below 1490 # this is more than twice as fast as the generic code below
934 sub { 1491 sub {
935 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1492 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
936 1493
937 $cb->($_[0], $1, $2); 1494 $cb->($_[0], "$1", "$2");
938 1 1495 1
939 } 1496 }
940 } else { 1497 } else {
941 $eol = quotemeta $eol unless ref $eol; 1498 $eol = quotemeta $eol unless ref $eol;
942 $eol = qr|^(.*?)($eol)|s; 1499 $eol = qr|^(.*?)($eol)|s;
943 1500
944 sub { 1501 sub {
945 $_[0]{rbuf} =~ s/$eol// or return; 1502 $_[0]{rbuf} =~ s/$eol// or return;
946 1503
947 $cb->($_[0], $1, $2); 1504 $cb->($_[0], "$1", "$2");
948 1 1505 1
949 } 1506 }
950 } 1507 }
951}; 1508};
952 1509
974the receive buffer when neither C<$accept> nor C<$reject> match, 1531the receive buffer when neither C<$accept> nor C<$reject> match,
975and everything preceding and including the match will be accepted 1532and everything preceding and including the match will be accepted
976unconditionally. This is useful to skip large amounts of data that you 1533unconditionally. This is useful to skip large amounts of data that you
977know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1534know cannot be matched, so that the C<$accept> or C<$reject> regex do not
978have to start matching from the beginning. This is purely an optimisation 1535have to start matching from the beginning. This is purely an optimisation
979and is usually worth only when you expect more than a few kilobytes. 1536and is usually worth it only when you expect more than a few kilobytes.
980 1537
981Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1538Example: expect a http header, which ends at C<\015\012\015\012>. Since we
982expect the header to be very large (it isn't in practise, but...), we use 1539expect the header to be very large (it isn't in practice, but...), we use
983a skip regex to skip initial portions. The skip regex is tricky in that 1540a skip regex to skip initial portions. The skip regex is tricky in that
984it only accepts something not ending in either \015 or \012, as these are 1541it only accepts something not ending in either \015 or \012, as these are
985required for the accept regex. 1542required for the accept regex.
986 1543
987 $handle->push_read (regex => 1544 $handle->push_read (regex =>
1000 1557
1001 sub { 1558 sub {
1002 # accept 1559 # accept
1003 if ($$rbuf =~ $accept) { 1560 if ($$rbuf =~ $accept) {
1004 $data .= substr $$rbuf, 0, $+[0], ""; 1561 $data .= substr $$rbuf, 0, $+[0], "";
1005 $cb->($self, $data); 1562 $cb->($_[0], $data);
1006 return 1; 1563 return 1;
1007 } 1564 }
1008 1565
1009 # reject 1566 # reject
1010 if ($reject && $$rbuf =~ $reject) { 1567 if ($reject && $$rbuf =~ $reject) {
1011 $self->_error (&Errno::EBADMSG); 1568 $_[0]->_error (Errno::EBADMSG);
1012 } 1569 }
1013 1570
1014 # skip 1571 # skip
1015 if ($skip && $$rbuf =~ $skip) { 1572 if ($skip && $$rbuf =~ $skip) {
1016 $data .= substr $$rbuf, 0, $+[0], ""; 1573 $data .= substr $$rbuf, 0, $+[0], "";
1032 my ($self, $cb) = @_; 1589 my ($self, $cb) = @_;
1033 1590
1034 sub { 1591 sub {
1035 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1592 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1036 if ($_[0]{rbuf} =~ /[^0-9]/) { 1593 if ($_[0]{rbuf} =~ /[^0-9]/) {
1037 $self->_error (&Errno::EBADMSG); 1594 $_[0]->_error (Errno::EBADMSG);
1038 } 1595 }
1039 return; 1596 return;
1040 } 1597 }
1041 1598
1042 my $len = $1; 1599 my $len = $1;
1043 1600
1044 $self->unshift_read (chunk => $len, sub { 1601 $_[0]->unshift_read (chunk => $len, sub {
1045 my $string = $_[1]; 1602 my $string = $_[1];
1046 $_[0]->unshift_read (chunk => 1, sub { 1603 $_[0]->unshift_read (chunk => 1, sub {
1047 if ($_[1] eq ",") { 1604 if ($_[1] eq ",") {
1048 $cb->($_[0], $string); 1605 $cb->($_[0], $string);
1049 } else { 1606 } else {
1050 $self->_error (&Errno::EBADMSG); 1607 $_[0]->_error (Errno::EBADMSG);
1051 } 1608 }
1052 }); 1609 });
1053 }); 1610 });
1054 1611
1055 1 1612 1
1061An octet string prefixed with an encoded length. The encoding C<$format> 1618An octet string prefixed with an encoded length. The encoding C<$format>
1062uses the same format as a Perl C<pack> format, but must specify a single 1619uses the same format as a Perl C<pack> format, but must specify a single
1063integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an 1620integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1064optional C<!>, C<< < >> or C<< > >> modifier). 1621optional C<!>, C<< < >> or C<< > >> modifier).
1065 1622
1066DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>. 1623For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1624EPP uses a prefix of C<N> (4 octtes).
1067 1625
1068Example: read a block of data prefixed by its length in BER-encoded 1626Example: read a block of data prefixed by its length in BER-encoded
1069format (very efficient). 1627format (very efficient).
1070 1628
1071 $handle->push_read (packstring => "w", sub { 1629 $handle->push_read (packstring => "w", sub {
1101 } 1659 }
1102}; 1660};
1103 1661
1104=item json => $cb->($handle, $hash_or_arrayref) 1662=item json => $cb->($handle, $hash_or_arrayref)
1105 1663
1106Reads a JSON object or array, decodes it and passes it to the callback. 1664Reads a JSON object or array, decodes it and passes it to the
1665callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1107 1666
1108If a C<json> object was passed to the constructor, then that will be used 1667If a C<json> object was passed to the constructor, then that will be used
1109for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1668for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1110 1669
1111This read type uses the incremental parser available with JSON version 1670This read type uses the incremental parser available with JSON version
1120=cut 1679=cut
1121 1680
1122register_read_type json => sub { 1681register_read_type json => sub {
1123 my ($self, $cb) = @_; 1682 my ($self, $cb) = @_;
1124 1683
1125 require JSON; 1684 my $json = $self->{json} ||= json_coder;
1126 1685
1127 my $data; 1686 my $data;
1128 my $rbuf = \$self->{rbuf}; 1687 my $rbuf = \$self->{rbuf};
1129 1688
1130 my $json = $self->{json} ||= JSON->new->utf8;
1131
1132 sub { 1689 sub {
1133 my $ref = $json->incr_parse ($self->{rbuf}); 1690 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1134 1691
1135 if ($ref) { 1692 if ($ref) {
1136 $self->{rbuf} = $json->incr_text; 1693 $_[0]{rbuf} = $json->incr_text;
1137 $json->incr_text = ""; 1694 $json->incr_text = "";
1138 $cb->($self, $ref); 1695 $cb->($_[0], $ref);
1139 1696
1140 1 1697 1
1698 } elsif ($@) {
1699 # error case
1700 $json->incr_skip;
1701
1702 $_[0]{rbuf} = $json->incr_text;
1703 $json->incr_text = "";
1704
1705 $_[0]->_error (Errno::EBADMSG);
1706
1707 ()
1141 } else { 1708 } else {
1142 $self->{rbuf} = ""; 1709 $_[0]{rbuf} = "";
1710
1143 () 1711 ()
1144 } 1712 }
1145 } 1713 }
1146}; 1714};
1147 1715
1156=cut 1724=cut
1157 1725
1158register_read_type storable => sub { 1726register_read_type storable => sub {
1159 my ($self, $cb) = @_; 1727 my ($self, $cb) = @_;
1160 1728
1161 require Storable; 1729 require Storable unless $Storable::VERSION;
1162 1730
1163 sub { 1731 sub {
1164 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1732 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1165 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1733 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1166 or return; 1734 or return;
1169 1737
1170 # bypass unshift if we already have the remaining chunk 1738 # bypass unshift if we already have the remaining chunk
1171 if ($format + $len <= length $_[0]{rbuf}) { 1739 if ($format + $len <= length $_[0]{rbuf}) {
1172 my $data = substr $_[0]{rbuf}, $format, $len; 1740 my $data = substr $_[0]{rbuf}, $format, $len;
1173 substr $_[0]{rbuf}, 0, $format + $len, ""; 1741 substr $_[0]{rbuf}, 0, $format + $len, "";
1742
1174 $cb->($_[0], Storable::thaw ($data)); 1743 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1744 or return $_[0]->_error (Errno::EBADMSG);
1175 } else { 1745 } else {
1176 # remove prefix 1746 # remove prefix
1177 substr $_[0]{rbuf}, 0, $format, ""; 1747 substr $_[0]{rbuf}, 0, $format, "";
1178 1748
1179 # read remaining chunk 1749 # read remaining chunk
1180 $_[0]->unshift_read (chunk => $len, sub { 1750 $_[0]->unshift_read (chunk => $len, sub {
1181 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1751 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1182 $cb->($_[0], $ref);
1183 } else {
1184 $self->_error (&Errno::EBADMSG); 1752 or $_[0]->_error (Errno::EBADMSG);
1185 }
1186 }); 1753 });
1187 } 1754 }
1188 1755
1189 1 1756 1
1190 } 1757 }
1191}; 1758};
1192 1759
1760=item tls_detect => $cb->($handle, $detect, $major, $minor)
1761
1762Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1763record without consuming anything. Only SSL version 3 or higher
1764is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1765SSL2-compatible framing is supported).
1766
1767If it detects that the input data is likely TLS, it calls the callback
1768with a true value for C<$detect> and the (on-wire) TLS version as second
1769and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
17703.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1771be definitely not TLS, it calls the callback with a false value for
1772C<$detect>.
1773
1774The callback could use this information to decide whether or not to start
1775TLS negotiation.
1776
1777In all cases the data read so far is passed to the following read
1778handlers.
1779
1780Usually you want to use the C<tls_autostart> read type instead.
1781
1782If you want to design a protocol that works in the presence of TLS
1783dtection, make sure that any non-TLS data doesn't start with the octet 22
1784(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1785read type does are a bit more strict, but might losen in the future to
1786accomodate protocol changes.
1787
1788This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1789L<Net::SSLeay>).
1790
1791=item tls_autostart => $tls[, $tls_ctx]
1792
1793Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1794to start tls by calling C<starttls> with the given arguments.
1795
1796In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1797been configured to accept, as servers do not normally send a handshake on
1798their own and ths cannot be detected in this way.
1799
1800See C<tls_detect> above for more details.
1801
1802Example: give the client a chance to start TLS before accepting a text
1803line.
1804
1805 $hdl->push_read (tls_detect => "accept");
1806 $hdl->push_read (line => sub {
1807 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1808 });
1809
1810=cut
1811
1812register_read_type tls_detect => sub {
1813 my ($self, $cb) = @_;
1814
1815 sub {
1816 # this regex matches a full or partial tls record
1817 if (
1818 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1819 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1820 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1821 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1822 ) {
1823 return if 3 != length $1; # partial match, can't decide yet
1824
1825 # full match, valid TLS record
1826 my ($major, $minor) = unpack "CC", $1;
1827 $cb->($self, "accept", $major + $minor * 0.1);
1828 } else {
1829 # mismatch == guaranteed not TLS
1830 $cb->($self, undef);
1831 }
1832
1833 1
1834 }
1835};
1836
1837register_read_type tls_autostart => sub {
1838 my ($self, @tls) = @_;
1839
1840 $RH{tls_detect}($self, sub {
1841 return unless $_[1];
1842 $_[0]->starttls (@tls);
1843 })
1844};
1845
1193=back 1846=back
1194 1847
1195=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1848=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1196 1849
1197This function (not method) lets you add your own types to C<push_read>. 1850Instead of one of the predefined types, you can also specify the name
1851of a package. AnyEvent will try to load the package and then expects to
1852find a function named C<anyevent_read_type> inside. If it isn't found, it
1853progressively tries to load the parent package until it either finds the
1854function (good) or runs out of packages (bad).
1198 1855
1199Whenever the given C<type> is used, C<push_read> will invoke the code 1856Whenever this type is used, C<push_read> will invoke the function with the
1200reference with the handle object, the callback and the remaining 1857handle object, the original callback and the remaining arguments.
1201arguments.
1202 1858
1203The code reference is supposed to return a callback (usually a closure) 1859The function is supposed to return a callback (usually a closure) that
1204that works as a plain read callback (see C<< ->push_read ($cb) >>). 1860works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1861mentally treat the function as a "configurable read type to read callback"
1862converter.
1205 1863
1206It should invoke the passed callback when it is done reading (remember to 1864It should invoke the original callback when it is done reading (remember
1207pass C<$handle> as first argument as all other callbacks do that). 1865to pass C<$handle> as first argument as all other callbacks do that,
1866although there is no strict requirement on this).
1208 1867
1209Note that this is a function, and all types registered this way will be
1210global, so try to use unique names.
1211
1212For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1868For examples, see the source of this module (F<perldoc -m
1213search for C<register_read_type>)). 1869AnyEvent::Handle>, search for C<register_read_type>)).
1214 1870
1215=item $handle->stop_read 1871=item $handle->stop_read
1216 1872
1217=item $handle->start_read 1873=item $handle->start_read
1218 1874
1224Note that AnyEvent::Handle will automatically C<start_read> for you when 1880Note that AnyEvent::Handle will automatically C<start_read> for you when
1225you change the C<on_read> callback or push/unshift a read callback, and it 1881you change the C<on_read> callback or push/unshift a read callback, and it
1226will automatically C<stop_read> for you when neither C<on_read> is set nor 1882will automatically C<stop_read> for you when neither C<on_read> is set nor
1227there are any read requests in the queue. 1883there are any read requests in the queue.
1228 1884
1885In older versions of this module (<= 5.3), these methods had no effect,
1886as TLS does not support half-duplex connections. In current versions they
1887work as expected, as this behaviour is required to avoid certain resource
1888attacks, where the program would be forced to read (and buffer) arbitrary
1889amounts of data before being able to send some data. The drawback is that
1890some readings of the the SSL/TLS specifications basically require this
1891attack to be working, as SSL/TLS implementations might stall sending data
1892during a rehandshake.
1893
1894As a guideline, during the initial handshake, you should not stop reading,
1895and as a client, it might cause problems, depending on your application.
1896
1229=cut 1897=cut
1230 1898
1231sub stop_read { 1899sub stop_read {
1232 my ($self) = @_; 1900 my ($self) = @_;
1233 1901
1235} 1903}
1236 1904
1237sub start_read { 1905sub start_read {
1238 my ($self) = @_; 1906 my ($self) = @_;
1239 1907
1240 unless ($self->{_rw} || $self->{_eof}) { 1908 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1241 Scalar::Util::weaken $self; 1909 Scalar::Util::weaken $self;
1242 1910
1243 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1911 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1244 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1912 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1245 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1913 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1246 1914
1247 if ($len > 0) { 1915 if ($len > 0) {
1248 $self->{_activity} = AnyEvent->now; 1916 $self->{_activity} = $self->{_ractivity} = AE::now;
1249 1917
1250 $self->{filter_r} 1918 if ($self->{tls}) {
1251 ? $self->{filter_r}($self, $rbuf) 1919 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1252 : $self->{_in_drain} || $self->_drain_rbuf; 1920
1921 &_dotls ($self);
1922 } else {
1923 $self->_drain_rbuf;
1924 }
1925
1926 if ($len == $self->{read_size}) {
1927 $self->{read_size} *= 2;
1928 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1929 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1930 }
1253 1931
1254 } elsif (defined $len) { 1932 } elsif (defined $len) {
1255 delete $self->{_rw}; 1933 delete $self->{_rw};
1256 $self->{_eof} = 1; 1934 $self->{_eof} = 1;
1257 $self->_drain_rbuf unless $self->{_in_drain}; 1935 $self->_drain_rbuf;
1258 1936
1259 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1937 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1260 return $self->_error ($!, 1); 1938 return $self->_error ($!, 1);
1261 } 1939 }
1262 }); 1940 };
1263 } 1941 }
1264} 1942}
1265 1943
1944our $ERROR_SYSCALL;
1945our $ERROR_WANT_READ;
1946
1947sub _tls_error {
1948 my ($self, $err) = @_;
1949
1950 return $self->_error ($!, 1)
1951 if $err == Net::SSLeay::ERROR_SYSCALL ();
1952
1953 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1954
1955 # reduce error string to look less scary
1956 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1957
1958 if ($self->{_on_starttls}) {
1959 (delete $self->{_on_starttls})->($self, undef, $err);
1960 &_freetls;
1961 } else {
1962 &_freetls;
1963 $self->_error (Errno::EPROTO, 1, $err);
1964 }
1965}
1966
1967# poll the write BIO and send the data if applicable
1968# also decode read data if possible
1969# this is basiclaly our TLS state machine
1970# more efficient implementations are possible with openssl,
1971# but not with the buggy and incomplete Net::SSLeay.
1266sub _dotls { 1972sub _dotls {
1267 my ($self) = @_; 1973 my ($self) = @_;
1268 1974
1269 my $buf; 1975 my $tmp;
1270 1976
1271 if (length $self->{_tls_wbuf}) { 1977 if (length $self->{_tls_wbuf}) {
1272 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1978 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1273 substr $self->{_tls_wbuf}, 0, $len, ""; 1979 substr $self->{_tls_wbuf}, 0, $tmp, "";
1274 } 1980 }
1275 }
1276 1981
1982 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1983 return $self->_tls_error ($tmp)
1984 if $tmp != $ERROR_WANT_READ
1985 && ($tmp != $ERROR_SYSCALL || $!);
1986 }
1987
1988 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1989 unless (length $tmp) {
1990 $self->{_on_starttls}
1991 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1992 &_freetls;
1993
1994 if ($self->{on_stoptls}) {
1995 $self->{on_stoptls}($self);
1996 return;
1997 } else {
1998 # let's treat SSL-eof as we treat normal EOF
1999 delete $self->{_rw};
2000 $self->{_eof} = 1;
2001 }
2002 }
2003
2004 $self->{_tls_rbuf} .= $tmp;
2005 $self->_drain_rbuf;
2006 $self->{tls} or return; # tls session might have gone away in callback
2007 }
2008
2009 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
2010 return $self->_tls_error ($tmp)
2011 if $tmp != $ERROR_WANT_READ
2012 && ($tmp != $ERROR_SYSCALL || $!);
2013
1277 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2014 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1278 $self->{wbuf} .= $buf; 2015 $self->{wbuf} .= $tmp;
1279 $self->_drain_wbuf; 2016 $self->_drain_wbuf;
2017 $self->{tls} or return; # tls session might have gone away in callback
1280 } 2018 }
1281 2019
1282 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { 2020 $self->{_on_starttls}
1283 if (length $buf) { 2021 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1284 $self->{rbuf} .= $buf; 2022 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1285 $self->_drain_rbuf unless $self->{_in_drain};
1286 } else {
1287 # let's treat SSL-eof as we treat normal EOF
1288 $self->{_eof} = 1;
1289 $self->_shutdown;
1290 return;
1291 }
1292 }
1293
1294 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1295
1296 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1297 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1298 return $self->_error ($!, 1);
1299 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1300 return $self->_error (&Errno::EIO, 1);
1301 }
1302
1303 # all others are fine for our purposes
1304 }
1305} 2023}
1306 2024
1307=item $handle->starttls ($tls[, $tls_ctx]) 2025=item $handle->starttls ($tls[, $tls_ctx])
1308 2026
1309Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2027Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1310object is created, you can also do that at a later time by calling 2028object is created, you can also do that at a later time by calling
1311C<starttls>. 2029C<starttls>. See the C<tls> constructor argument for general info.
2030
2031Starting TLS is currently an asynchronous operation - when you push some
2032write data and then call C<< ->starttls >> then TLS negotiation will start
2033immediately, after which the queued write data is then sent. This might
2034change in future versions, so best make sure you have no outstanding write
2035data when calling this method.
1312 2036
1313The first argument is the same as the C<tls> constructor argument (either 2037The first argument is the same as the C<tls> constructor argument (either
1314C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2038C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1315 2039
1316The second argument is the optional C<Net::SSLeay::CTX> object that is 2040The second argument is the optional C<AnyEvent::TLS> object that is used
1317used when AnyEvent::Handle has to create its own TLS connection object. 2041when AnyEvent::Handle has to create its own TLS connection object, or
2042a hash reference with C<< key => value >> pairs that will be used to
2043construct a new context.
1318 2044
1319The TLS connection object will end up in C<< $handle->{tls} >> after this 2045The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1320call and can be used or changed to your liking. Note that the handshake 2046context in C<< $handle->{tls_ctx} >> after this call and can be used or
1321might have already started when this function returns. 2047changed to your liking. Note that the handshake might have already started
2048when this function returns.
1322 2049
2050Due to bugs in OpenSSL, it might or might not be possible to do multiple
2051handshakes on the same stream. It is best to not attempt to use the
2052stream after stopping TLS.
2053
2054This method may invoke callbacks (and therefore the handle might be
2055destroyed after it returns).
2056
1323=cut 2057=cut
2058
2059our %TLS_CACHE; #TODO not yet documented, should we?
1324 2060
1325sub starttls { 2061sub starttls {
1326 my ($self, $ssl, $ctx) = @_; 2062 my ($self, $tls, $ctx) = @_;
1327 2063
1328 $self->stoptls; 2064 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
2065 if $self->{tls};
1329 2066
1330 if ($ssl eq "accept") { 2067 unless (defined $AnyEvent::TLS::VERSION) {
1331 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 2068 eval {
1332 Net::SSLeay::set_accept_state ($ssl); 2069 require Net::SSLeay;
1333 } elsif ($ssl eq "connect") { 2070 require AnyEvent::TLS;
1334 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 2071 1
1335 Net::SSLeay::set_connect_state ($ssl); 2072 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2073 }
2074
2075 $self->{tls} = $tls;
2076 $self->{tls_ctx} = $ctx if @_ > 2;
2077
2078 return unless $self->{fh};
2079
2080 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
2081 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
2082
2083 $tls = delete $self->{tls};
2084 $ctx = $self->{tls_ctx};
2085
2086 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
2087
2088 if ("HASH" eq ref $ctx) {
2089 if ($ctx->{cache}) {
2090 my $key = $ctx+0;
2091 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
2092 } else {
2093 $ctx = new AnyEvent::TLS %$ctx;
2094 }
2095 }
1336 } 2096
1337 2097 $self->{tls_ctx} = $ctx || TLS_CTX ();
1338 $self->{tls} = $ssl; 2098 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1339 2099
1340 # basically, this is deep magic (because SSL_read should have the same issues) 2100 # basically, this is deep magic (because SSL_read should have the same issues)
1341 # but the openssl maintainers basically said: "trust us, it just works". 2101 # but the openssl maintainers basically said: "trust us, it just works".
1342 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2102 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1343 # and mismaintained ssleay-module doesn't even offer them). 2103 # and mismaintained ssleay-module doesn't even offer them).
1344 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 2104 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
2105 #
2106 # in short: this is a mess.
2107 #
2108 # note that we do not try to keep the length constant between writes as we are required to do.
2109 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
2110 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
2111 # have identity issues in that area.
1345 Net::SSLeay::CTX_set_mode ($self->{tls}, 2112# Net::SSLeay::CTX_set_mode ($ssl,
1346 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2113# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1347 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2114# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
2115 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1348 2116
1349 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2117 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1350 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2118 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1351 2119
2120 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2121 $self->{rbuf} = "";
2122
1352 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2123 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1353 2124
1354 $self->{filter_w} = sub { 2125 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1355 $_[0]{_tls_wbuf} .= ${$_[1]}; 2126 if $self->{on_starttls};
1356 &_dotls; 2127
1357 }; 2128 &_dotls; # need to trigger the initial handshake
1358 $self->{filter_r} = sub { 2129 $self->start_read; # make sure we actually do read
1359 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1360 &_dotls;
1361 };
1362} 2130}
1363 2131
1364=item $handle->stoptls 2132=item $handle->stoptls
1365 2133
1366Destroys the SSL connection, if any. Partial read or write data will be 2134Shuts down the SSL connection - this makes a proper EOF handshake by
1367lost. 2135sending a close notify to the other side, but since OpenSSL doesn't
2136support non-blocking shut downs, it is not guaranteed that you can re-use
2137the stream afterwards.
2138
2139This method may invoke callbacks (and therefore the handle might be
2140destroyed after it returns).
1368 2141
1369=cut 2142=cut
1370 2143
1371sub stoptls { 2144sub stoptls {
1372 my ($self) = @_; 2145 my ($self) = @_;
1373 2146
1374 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 2147 if ($self->{tls} && $self->{fh}) {
2148 Net::SSLeay::shutdown ($self->{tls});
1375 2149
1376 delete $self->{_rbio}; 2150 &_dotls;
1377 delete $self->{_wbio}; 2151
1378 delete $self->{_tls_wbuf}; 2152# # we don't give a shit. no, we do, but we can't. no...#d#
1379 delete $self->{filter_r}; 2153# # we, we... have to use openssl :/#d#
1380 delete $self->{filter_w}; 2154# &_freetls;#d#
2155 }
1381} 2156}
2157
2158sub _freetls {
2159 my ($self) = @_;
2160
2161 return unless $self->{tls};
2162
2163 $self->{tls_ctx}->_put_session (delete $self->{tls})
2164 if $self->{tls} > 0;
2165
2166 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2167}
2168
2169=item $handle->resettls
2170
2171This rarely-used method simply resets and TLS state on the handle, usually
2172causing data loss.
2173
2174One case where it may be useful is when you want to skip over the data in
2175the stream but you are not interested in interpreting it, so data loss is
2176no concern.
2177
2178=cut
2179
2180*resettls = \&_freetls;
1382 2181
1383sub DESTROY { 2182sub DESTROY {
1384 my $self = shift; 2183 my ($self) = @_;
1385 2184
1386 $self->stoptls; 2185 &_freetls;
1387 2186
1388 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 2187 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1389 2188
1390 if ($linger && length $self->{wbuf}) { 2189 if ($linger && length $self->{wbuf} && $self->{fh}) {
1391 my $fh = delete $self->{fh}; 2190 my $fh = delete $self->{fh};
1392 my $wbuf = delete $self->{wbuf}; 2191 my $wbuf = delete $self->{wbuf};
1393 2192
1394 my @linger; 2193 my @linger;
1395 2194
1396 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2195 push @linger, AE::io $fh, 1, sub {
1397 my $len = syswrite $fh, $wbuf, length $wbuf; 2196 my $len = syswrite $fh, $wbuf, length $wbuf;
1398 2197
1399 if ($len > 0) { 2198 if ($len > 0) {
1400 substr $wbuf, 0, $len, ""; 2199 substr $wbuf, 0, $len, "";
1401 } else { 2200 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1402 @linger = (); # end 2201 @linger = (); # end
1403 } 2202 }
2203 };
2204 push @linger, AE::timer $linger, 0, sub {
2205 @linger = ();
2206 };
2207 }
2208}
2209
2210=item $handle->destroy
2211
2212Shuts down the handle object as much as possible - this call ensures that
2213no further callbacks will be invoked and as many resources as possible
2214will be freed. Any method you will call on the handle object after
2215destroying it in this way will be silently ignored (and it will return the
2216empty list).
2217
2218Normally, you can just "forget" any references to an AnyEvent::Handle
2219object and it will simply shut down. This works in fatal error and EOF
2220callbacks, as well as code outside. It does I<NOT> work in a read or write
2221callback, so when you want to destroy the AnyEvent::Handle object from
2222within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
2223that case.
2224
2225Destroying the handle object in this way has the advantage that callbacks
2226will be removed as well, so if those are the only reference holders (as
2227is common), then one doesn't need to do anything special to break any
2228reference cycles.
2229
2230The handle might still linger in the background and write out remaining
2231data, as specified by the C<linger> option, however.
2232
2233=cut
2234
2235sub destroy {
2236 my ($self) = @_;
2237
2238 $self->DESTROY;
2239 %$self = ();
2240 bless $self, "AnyEvent::Handle::destroyed";
2241}
2242
2243sub AnyEvent::Handle::destroyed::AUTOLOAD {
2244 #nop
2245}
2246
2247=item $handle->destroyed
2248
2249Returns false as long as the handle hasn't been destroyed by a call to C<<
2250->destroy >>, true otherwise.
2251
2252Can be useful to decide whether the handle is still valid after some
2253callback possibly destroyed the handle. For example, C<< ->push_write >>,
2254C<< ->starttls >> and other methods can call user callbacks, which in turn
2255can destroy the handle, so work can be avoided by checking sometimes:
2256
2257 $hdl->starttls ("accept");
2258 return if $hdl->destroyed;
2259 $hdl->push_write (...
2260
2261Note that the call to C<push_write> will silently be ignored if the handle
2262has been destroyed, so often you can just ignore the possibility of the
2263handle being destroyed.
2264
2265=cut
2266
2267sub destroyed { 0 }
2268sub AnyEvent::Handle::destroyed::destroyed { 1 }
2269
2270=item AnyEvent::Handle::TLS_CTX
2271
2272This function creates and returns the AnyEvent::TLS object used by default
2273for TLS mode.
2274
2275The context is created by calling L<AnyEvent::TLS> without any arguments.
2276
2277=cut
2278
2279our $TLS_CTX;
2280
2281sub TLS_CTX() {
2282 $TLS_CTX ||= do {
2283 require AnyEvent::TLS;
2284
2285 new AnyEvent::TLS
2286 }
2287}
2288
2289=back
2290
2291
2292=head1 NONFREQUENTLY ASKED QUESTIONS
2293
2294=over 4
2295
2296=item I C<undef> the AnyEvent::Handle reference inside my callback and
2297still get further invocations!
2298
2299That's because AnyEvent::Handle keeps a reference to itself when handling
2300read or write callbacks.
2301
2302It is only safe to "forget" the reference inside EOF or error callbacks,
2303from within all other callbacks, you need to explicitly call the C<<
2304->destroy >> method.
2305
2306=item Why is my C<on_eof> callback never called?
2307
2308Probably because your C<on_error> callback is being called instead: When
2309you have outstanding requests in your read queue, then an EOF is
2310considered an error as you clearly expected some data.
2311
2312To avoid this, make sure you have an empty read queue whenever your handle
2313is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2314an C<on_read> handler that simply pushes the first read requests in the
2315queue.
2316
2317See also the next question, which explains this in a bit more detail.
2318
2319=item How can I serve requests in a loop?
2320
2321Most protocols consist of some setup phase (authentication for example)
2322followed by a request handling phase, where the server waits for requests
2323and handles them, in a loop.
2324
2325There are two important variants: The first (traditional, better) variant
2326handles requests until the server gets some QUIT command, causing it to
2327close the connection first (highly desirable for a busy TCP server). A
2328client dropping the connection is an error, which means this variant can
2329detect an unexpected detection close.
2330
2331To handle this case, always make sure you have a non-empty read queue, by
2332pushing the "read request start" handler on it:
2333
2334 # we assume a request starts with a single line
2335 my @start_request; @start_request = (line => sub {
2336 my ($hdl, $line) = @_;
2337
2338 ... handle request
2339
2340 # push next request read, possibly from a nested callback
2341 $hdl->push_read (@start_request);
2342 });
2343
2344 # auth done, now go into request handling loop
2345 # now push the first @start_request
2346 $hdl->push_read (@start_request);
2347
2348By always having an outstanding C<push_read>, the handle always expects
2349some data and raises the C<EPIPE> error when the connction is dropped
2350unexpectedly.
2351
2352The second variant is a protocol where the client can drop the connection
2353at any time. For TCP, this means that the server machine may run out of
2354sockets easier, and in general, it means you cannot distinguish a protocl
2355failure/client crash from a normal connection close. Nevertheless, these
2356kinds of protocols are common (and sometimes even the best solution to the
2357problem).
2358
2359Having an outstanding read request at all times is possible if you ignore
2360C<EPIPE> errors, but this doesn't help with when the client drops the
2361connection during a request, which would still be an error.
2362
2363A better solution is to push the initial request read in an C<on_read>
2364callback. This avoids an error, as when the server doesn't expect data
2365(i.e. is idly waiting for the next request, an EOF will not raise an
2366error, but simply result in an C<on_eof> callback. It is also a bit slower
2367and simpler:
2368
2369 # auth done, now go into request handling loop
2370 $hdl->on_read (sub {
2371 my ($hdl) = @_;
2372
2373 # called each time we receive data but the read queue is empty
2374 # simply start read the request
2375
2376 $hdl->push_read (line => sub {
2377 my ($hdl, $line) = @_;
2378
2379 ... handle request
2380
2381 # do nothing special when the request has been handled, just
2382 # let the request queue go empty.
1404 }); 2383 });
1405 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1406 @linger = ();
1407 }); 2384 });
2385
2386=item I get different callback invocations in TLS mode/Why can't I pause
2387reading?
2388
2389Unlike, say, TCP, TLS connections do not consist of two independent
2390communication channels, one for each direction. Or put differently, the
2391read and write directions are not independent of each other: you cannot
2392write data unless you are also prepared to read, and vice versa.
2393
2394This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2395callback invocations when you are not expecting any read data - the reason
2396is that AnyEvent::Handle always reads in TLS mode.
2397
2398During the connection, you have to make sure that you always have a
2399non-empty read-queue, or an C<on_read> watcher. At the end of the
2400connection (or when you no longer want to use it) you can call the
2401C<destroy> method.
2402
2403=item How do I read data until the other side closes the connection?
2404
2405If you just want to read your data into a perl scalar, the easiest way
2406to achieve this is by setting an C<on_read> callback that does nothing,
2407clearing the C<on_eof> callback and in the C<on_error> callback, the data
2408will be in C<$_[0]{rbuf}>:
2409
2410 $handle->on_read (sub { });
2411 $handle->on_eof (undef);
2412 $handle->on_error (sub {
2413 my $data = delete $_[0]{rbuf};
2414 });
2415
2416Note that this example removes the C<rbuf> member from the handle object,
2417which is not normally allowed by the API. It is expressly permitted in
2418this case only, as the handle object needs to be destroyed afterwards.
2419
2420The reason to use C<on_error> is that TCP connections, due to latencies
2421and packets loss, might get closed quite violently with an error, when in
2422fact all data has been received.
2423
2424It is usually better to use acknowledgements when transferring data,
2425to make sure the other side hasn't just died and you got the data
2426intact. This is also one reason why so many internet protocols have an
2427explicit QUIT command.
2428
2429=item I don't want to destroy the handle too early - how do I wait until
2430all data has been written?
2431
2432After writing your last bits of data, set the C<on_drain> callback
2433and destroy the handle in there - with the default setting of
2434C<low_water_mark> this will be called precisely when all data has been
2435written to the socket:
2436
2437 $handle->push_write (...);
2438 $handle->on_drain (sub {
2439 AE::log debug => "All data submitted to the kernel.";
2440 undef $handle;
2441 });
2442
2443If you just want to queue some data and then signal EOF to the other side,
2444consider using C<< ->push_shutdown >> instead.
2445
2446=item I want to contact a TLS/SSL server, I don't care about security.
2447
2448If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2449connect to it and then create the AnyEvent::Handle with the C<tls>
2450parameter:
2451
2452 tcp_connect $host, $port, sub {
2453 my ($fh) = @_;
2454
2455 my $handle = new AnyEvent::Handle
2456 fh => $fh,
2457 tls => "connect",
2458 on_error => sub { ... };
2459
2460 $handle->push_write (...);
1408 } 2461 };
1409}
1410 2462
1411=item AnyEvent::Handle::TLS_CTX 2463=item I want to contact a TLS/SSL server, I do care about security.
1412 2464
1413This function creates and returns the Net::SSLeay::CTX object used by 2465Then you should additionally enable certificate verification, including
1414default for TLS mode. 2466peername verification, if the protocol you use supports it (see
2467L<AnyEvent::TLS>, C<verify_peername>).
1415 2468
1416The context is created like this: 2469E.g. for HTTPS:
1417 2470
1418 Net::SSLeay::load_error_strings; 2471 tcp_connect $host, $port, sub {
1419 Net::SSLeay::SSLeay_add_ssl_algorithms; 2472 my ($fh) = @_;
1420 Net::SSLeay::randomize;
1421 2473
1422 my $CTX = Net::SSLeay::CTX_new; 2474 my $handle = new AnyEvent::Handle
2475 fh => $fh,
2476 peername => $host,
2477 tls => "connect",
2478 tls_ctx => { verify => 1, verify_peername => "https" },
2479 ...
1423 2480
1424 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL 2481Note that you must specify the hostname you connected to (or whatever
2482"peername" the protocol needs) as the C<peername> argument, otherwise no
2483peername verification will be done.
1425 2484
1426=cut 2485The above will use the system-dependent default set of trusted CA
2486certificates. If you want to check against a specific CA, add the
2487C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
1427 2488
1428our $TLS_CTX; 2489 tls_ctx => {
2490 verify => 1,
2491 verify_peername => "https",
2492 ca_file => "my-ca-cert.pem",
2493 },
1429 2494
1430sub TLS_CTX() { 2495=item I want to create a TLS/SSL server, how do I do that?
1431 $TLS_CTX || do {
1432 require Net::SSLeay;
1433 2496
1434 Net::SSLeay::load_error_strings (); 2497Well, you first need to get a server certificate and key. You have
1435 Net::SSLeay::SSLeay_add_ssl_algorithms (); 2498three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
1436 Net::SSLeay::randomize (); 2499self-signed certificate (cheap. check the search engine of your choice,
2500there are many tutorials on the net) or c) make your own CA (tinyca2 is a
2501nice program for that purpose).
1437 2502
1438 $TLS_CTX = Net::SSLeay::CTX_new (); 2503Then create a file with your private key (in PEM format, see
2504L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
2505file should then look like this:
1439 2506
1440 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ()); 2507 -----BEGIN RSA PRIVATE KEY-----
2508 ...header data
2509 ... lots of base64'y-stuff
2510 -----END RSA PRIVATE KEY-----
1441 2511
1442 $TLS_CTX 2512 -----BEGIN CERTIFICATE-----
1443 } 2513 ... lots of base64'y-stuff
1444} 2514 -----END CERTIFICATE-----
2515
2516The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
2517specify this file as C<cert_file>:
2518
2519 tcp_server undef, $port, sub {
2520 my ($fh) = @_;
2521
2522 my $handle = new AnyEvent::Handle
2523 fh => $fh,
2524 tls => "accept",
2525 tls_ctx => { cert_file => "my-server-keycert.pem" },
2526 ...
2527
2528When you have intermediate CA certificates that your clients might not
2529know about, just append them to the C<cert_file>.
1445 2530
1446=back 2531=back
1447 2532
1448=head1 SUBCLASSING AnyEvent::Handle 2533=head1 SUBCLASSING AnyEvent::Handle
1449 2534
1468 2553
1469=item * all members not documented here and not prefixed with an underscore 2554=item * all members not documented here and not prefixed with an underscore
1470are free to use in subclasses. 2555are free to use in subclasses.
1471 2556
1472Of course, new versions of AnyEvent::Handle may introduce more "public" 2557Of course, new versions of AnyEvent::Handle may introduce more "public"
1473member variables, but thats just life, at least it is documented. 2558member variables, but that's just life. At least it is documented.
1474 2559
1475=back 2560=back
1476 2561
1477=head1 AUTHOR 2562=head1 AUTHOR
1478 2563
1479Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2564Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1480 2565
1481=cut 2566=cut
1482 2567
14831; # End of AnyEvent::Handle 25681
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