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Revision 1.82 by root, Thu Aug 21 18:45:16 2008 UTC vs.
Revision 1.232 by root, Fri Mar 30 03:11:17 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 = 4.232;
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 => "Got 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
84For sockets, this just means that the other side has stopped sending data, 124The return value of this callback should be the connect timeout value in
85you can still try to write data, and, in fact, one can return from the eof 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
86callback and continue writing data, as only the read part has been shut 126default timeout is to be used).
87down.
88 127
89While not mandatory, it is I<highly> recommended to set an eof callback, 128=item on_connect => $cb->($handle, $host, $port, $retry->())
90otherwise you might end up with a closed socket while you are still
91waiting for data.
92 129
93If an EOF condition has been detected but no C<on_eof> callback has been 130This callback is called when a connection has been successfully established.
94set, then a fatal error will be raised with C<$!> set to <0>.
95 131
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
96=item on_error => $cb->($handle, $fatal) 160=item on_error => $cb->($handle, $fatal, $message)
97 161
98This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
99occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
100connect or a read error. 164connect, or a read error.
101 165
102Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
103fatal errors the handle object will be shut down and will not be usable 167fatal errors the handle object will be destroyed (by a call to C<< ->
104(but you are free to look at the current C< ->rbuf >). Examples of fatal 168destroy >>) after invoking the error callback (which means you are free to
105errors are an EOF condition with active (but unsatisifable) read watchers 169examine the handle object). Examples of fatal errors are an EOF condition
106(C<EPIPE>) or I/O errors. 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
107 173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well. It is
176recommended to always output the C<$message> argument in human-readable
177error messages (it's usually the same as C<"$!">).
178
108Non-fatal errors can be retried by simply returning, but it is recommended 179Non-fatal errors can be retried by returning, but it is recommended
109to simply ignore this parameter and instead abondon the handle object 180to simply ignore this parameter and instead abondon the handle object
110when this callback is invoked. Examples of non-fatal errors are timeouts 181when this callback is invoked. Examples of non-fatal errors are timeouts
111C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 182C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
112 183
113On callback entrance, the value of C<$!> contains the operating system 184On entry to the callback, the value of C<$!> contains the operating
114error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). 185system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
186C<EPROTO>).
115 187
116While not mandatory, it is I<highly> recommended to set this callback, as 188While not mandatory, it is I<highly> recommended to set this callback, as
117you will not be notified of errors otherwise. The default simply calls 189you will not be notified of errors otherwise. The default just calls
118C<croak>. 190C<croak>.
119 191
120=item on_read => $cb->($handle) 192=item on_read => $cb->($handle)
121 193
122This sets the default read callback, which is called when data arrives 194This sets the default read callback, which is called when data arrives
123and no read request is in the queue (unlike read queue callbacks, this 195and no read request is in the queue (unlike read queue callbacks, this
124callback will only be called when at least one octet of data is in the 196callback will only be called when at least one octet of data is in the
125read buffer). 197read buffer).
126 198
127To access (and remove data from) the read buffer, use the C<< ->rbuf >> 199To access (and remove data from) the read buffer, use the C<< ->rbuf >>
128method or access the C<$handle->{rbuf}> member directly. 200method or access the C<< $handle->{rbuf} >> member directly. Note that you
201must not enlarge or modify the read buffer, you can only remove data at
202the beginning from it.
129 203
204You can also call C<< ->push_read (...) >> or any other function that
205modifies the read queue. Or do both. Or ...
206
130When an EOF condition is detected then AnyEvent::Handle will first try to 207When an EOF condition is detected, AnyEvent::Handle will first try to
131feed all the remaining data to the queued callbacks and C<on_read> before 208feed all the remaining data to the queued callbacks and C<on_read> before
132calling the C<on_eof> callback. If no progress can be made, then a fatal 209calling the C<on_eof> callback. If no progress can be made, then a fatal
133error will be raised (with C<$!> set to C<EPIPE>). 210error will be raised (with C<$!> set to C<EPIPE>).
134 211
212Note that, unlike requests in the read queue, an C<on_read> callback
213doesn't mean you I<require> some data: if there is an EOF and there
214are outstanding read requests then an error will be flagged. With an
215C<on_read> callback, the C<on_eof> callback will be invoked.
216
217=item on_eof => $cb->($handle)
218
219Set the callback to be called when an end-of-file condition is detected,
220i.e. in the case of a socket, when the other side has closed the
221connection cleanly, and there are no outstanding read requests in the
222queue (if there are read requests, then an EOF counts as an unexpected
223connection close and will be flagged as an error).
224
225For sockets, this just means that the other side has stopped sending data,
226you can still try to write data, and, in fact, one can return from the EOF
227callback and continue writing data, as only the read part has been shut
228down.
229
230If an EOF condition has been detected but no C<on_eof> callback has been
231set, then a fatal error will be raised with C<$!> set to <0>.
232
135=item on_drain => $cb->($handle) 233=item on_drain => $cb->($handle)
136 234
137This sets the callback that is called when the write buffer becomes empty 235This sets the callback that is called once when the write buffer becomes
138(or when the callback is set and the buffer is empty already). 236empty (and immediately when the handle object is created).
139 237
140To append to the write buffer, use the C<< ->push_write >> method. 238To append to the write buffer, use the C<< ->push_write >> method.
141 239
142This callback is useful when you don't want to put all of your write data 240This callback is useful when you don't want to put all of your write data
143into the queue at once, for example, when you want to write the contents 241into the queue at once, for example, when you want to write the contents
145memory and push it into the queue, but instead only read more data from 243memory and push it into the queue, but instead only read more data from
146the file when the write queue becomes empty. 244the file when the write queue becomes empty.
147 245
148=item timeout => $fractional_seconds 246=item timeout => $fractional_seconds
149 247
248=item rtimeout => $fractional_seconds
249
250=item wtimeout => $fractional_seconds
251
150If non-zero, then this enables an "inactivity" timeout: whenever this many 252If non-zero, then these enables an "inactivity" timeout: whenever this
151seconds pass without a successful read or write on the underlying file 253many seconds pass without a successful read or write on the underlying
152handle, the C<on_timeout> callback will be invoked (and if that one is 254file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
153missing, an C<ETIMEDOUT> error will be raised). 255will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
256error will be raised).
154 257
258There are three variants of the timeouts that work independently of each
259other, for both read and write (triggered when nothing was read I<OR>
260written), just read (triggered when nothing was read), and just write:
261C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
262C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
263C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
264
155Note that timeout processing is also active when you currently do not have 265Note that timeout processing is active even when you do not have any
156any outstanding read or write requests: If you plan to keep the connection 266outstanding read or write requests: If you plan to keep the connection
157idle then you should disable the timout temporarily or ignore the timeout 267idle then you should disable the timeout temporarily or ignore the
158in the C<on_timeout> callback. 268timeout in the corresponding C<on_timeout> callback, in which case
269AnyEvent::Handle will simply restart the timeout.
159 270
160Zero (the default) disables this timeout. 271Zero (the default) disables the corresponding timeout.
161 272
162=item on_timeout => $cb->($handle) 273=item on_timeout => $cb->($handle)
274
275=item on_rtimeout => $cb->($handle)
276
277=item on_wtimeout => $cb->($handle)
163 278
164Called whenever the inactivity timeout passes. If you return from this 279Called whenever the inactivity timeout passes. If you return from this
165callback, then the timeout will be reset as if some activity had happened, 280callback, then the timeout will be reset as if some activity had happened,
166so this condition is not fatal in any way. 281so this condition is not fatal in any way.
167 282
168=item rbuf_max => <bytes> 283=item rbuf_max => <bytes>
169 284
170If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 285If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
171when the read buffer ever (strictly) exceeds this size. This is useful to 286when the read buffer ever (strictly) exceeds this size. This is useful to
172avoid denial-of-service attacks. 287avoid some forms of denial-of-service attacks.
173 288
174For example, a server accepting connections from untrusted sources should 289For example, a server accepting connections from untrusted sources should
175be configured to accept only so-and-so much data that it cannot act on 290be configured to accept only so-and-so much data that it cannot act on
176(for example, when expecting a line, an attacker could send an unlimited 291(for example, when expecting a line, an attacker could send an unlimited
177amount of data without a callback ever being called as long as the line 292amount of data without a callback ever being called as long as the line
178isn't finished). 293isn't finished).
179 294
295=item wbuf_max => <bytes>
296
297If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
298when the write buffer ever (strictly) exceeds this size. This is useful to
299avoid some forms of denial-of-service attacks.
300
301Although the units of this parameter is bytes, this is the I<raw> number
302of bytes not yet accepted by the kernel. This can make a difference when
303you e.g. use TLS, as TLS typically makes your write data larger (but it
304can also make it smaller due to compression).
305
306As an example of when this limit is useful, take a chat server that sends
307chat messages to a client. If the client does not read those in a timely
308manner then the send buffer in the server would grow unbounded.
309
180=item autocork => <boolean> 310=item autocork => <boolean>
181 311
182When disabled (the default), then C<push_write> will try to immediately 312When disabled (the default), C<push_write> will try to immediately
183write the data to the handle if possible. This avoids having to register 313write the data to the handle if possible. This avoids having to register
184a write watcher and wait for the next event loop iteration, but can be 314a write watcher and wait for the next event loop iteration, but can
185inefficient if you write multiple small chunks (this disadvantage is 315be inefficient if you write multiple small chunks (on the wire, this
186usually avoided by your kernel's nagle algorithm, see C<low_delay>). 316disadvantage is usually avoided by your kernel's nagle algorithm, see
317C<no_delay>, but this option can save costly syscalls).
187 318
188When enabled, then writes will always be queued till the next event loop 319When enabled, writes will always be queued till the next event loop
189iteration. This is efficient when you do many small writes per iteration, 320iteration. This is efficient when you do many small writes per iteration,
190but less efficient when you do a single write only. 321but less efficient when you do a single write only per iteration (or when
322the write buffer often is full). It also increases write latency.
191 323
192=item no_delay => <boolean> 324=item no_delay => <boolean>
193 325
194When doing small writes on sockets, your operating system kernel might 326When doing small writes on sockets, your operating system kernel might
195wait a bit for more data before actually sending it out. This is called 327wait a bit for more data before actually sending it out. This is called
196the Nagle algorithm, and usually it is beneficial. 328the Nagle algorithm, and usually it is beneficial.
197 329
198In some situations you want as low a delay as possible, which cna be 330In some situations you want as low a delay as possible, which can be
199accomplishd by setting this option to true. 331accomplishd by setting this option to a true value.
200 332
201The default is your opertaing system's default behaviour, this option 333The default is your operating system's default behaviour (most likely
202explicitly enables or disables it, if possible. 334enabled). This option explicitly enables or disables it, if possible.
335
336=item keepalive => <boolean>
337
338Enables (default disable) the SO_KEEPALIVE option on the stream socket:
339normally, TCP connections have no time-out once established, so TCP
340connections, once established, can stay alive forever even when the other
341side has long gone. TCP keepalives are a cheap way to take down long-lived
342TCP connections when the other side becomes unreachable. While the default
343is OS-dependent, TCP keepalives usually kick in after around two hours,
344and, if the other side doesn't reply, take down the TCP connection some 10
345to 15 minutes later.
346
347It is harmless to specify this option for file handles that do not support
348keepalives, and enabling it on connections that are potentially long-lived
349is usually a good idea.
350
351=item oobinline => <boolean>
352
353BSD majorly fucked up the implementation of TCP urgent data. The result
354is that almost no OS implements TCP according to the specs, and every OS
355implements it slightly differently.
356
357If you want to handle TCP urgent data, then setting this flag (the default
358is enabled) gives you the most portable way of getting urgent data, by
359putting it into the stream.
360
361Since BSD emulation of OOB data on top of TCP's urgent data can have
362security implications, AnyEvent::Handle sets this flag automatically
363unless explicitly specified. Note that setting this flag after
364establishing a connection I<may> be a bit too late (data loss could
365already have occured on BSD systems), but at least it will protect you
366from most attacks.
203 367
204=item read_size => <bytes> 368=item read_size => <bytes>
205 369
206The default read block size (the amount of bytes this module will try to read 370The initial read block size, the number of bytes this module will try
207during each (loop iteration). Default: C<8192>. 371to read during each loop iteration. Each handle object will consume
372at least this amount of memory for the read buffer as well, so when
373handling many connections watch out for memory requirements). See also
374C<max_read_size>. Default: C<2048>.
375
376=item max_read_size => <bytes>
377
378The maximum read buffer size used by the dynamic adjustment
379algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
380one go it will double C<read_size> up to the maximum given by this
381option. Default: C<131072> or C<read_size>, whichever is higher.
208 382
209=item low_water_mark => <bytes> 383=item low_water_mark => <bytes>
210 384
211Sets the amount of bytes (default: C<0>) that make up an "empty" write 385Sets the number of bytes (default: C<0>) that make up an "empty" write
212buffer: If the write reaches this size or gets even samller it is 386buffer: If the buffer reaches this size or gets even samller it is
213considered empty. 387considered empty.
214 388
389Sometimes it can be beneficial (for performance reasons) to add data to
390the write buffer before it is fully drained, but this is a rare case, as
391the operating system kernel usually buffers data as well, so the default
392is good in almost all cases.
393
215=item linger => <seconds> 394=item linger => <seconds>
216 395
217If non-zero (default: C<3600>), then the destructor of the 396If this is non-zero (default: C<3600>), the destructor of the
218AnyEvent::Handle object will check wether there is still outstanding write 397AnyEvent::Handle object will check whether there is still outstanding
219data and will install a watcher that will write out this data. No errors 398write data and will install a watcher that will write this data to the
220will be reported (this mostly matches how the operating system treats 399socket. No errors will be reported (this mostly matches how the operating
221outstanding data at socket close time). 400system treats outstanding data at socket close time).
222 401
223This will not work for partial TLS data that could not yet been 402This will not work for partial TLS data that could not be encoded
224encoded. This data will be lost. 403yet. This data will be lost. Calling the C<stoptls> method in time might
404help.
405
406=item peername => $string
407
408A string used to identify the remote site - usually the DNS hostname
409(I<not> IDN!) used to create the connection, rarely the IP address.
410
411Apart from being useful in error messages, this string is also used in TLS
412peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
413verification will be skipped when C<peername> is not specified or is
414C<undef>.
225 415
226=item tls => "accept" | "connect" | Net::SSLeay::SSL object 416=item tls => "accept" | "connect" | Net::SSLeay::SSL object
227 417
228When this parameter is given, it enables TLS (SSL) mode, that means it 418When this parameter is given, it enables TLS (SSL) mode, that means
229will start making tls handshake and will transparently encrypt/decrypt 419AnyEvent will start a TLS handshake as soon as the connection has been
230data. 420established and will transparently encrypt/decrypt data afterwards.
421
422All TLS protocol errors will be signalled as C<EPROTO>, with an
423appropriate error message.
231 424
232TLS mode requires Net::SSLeay to be installed (it will be loaded 425TLS mode requires Net::SSLeay to be installed (it will be loaded
233automatically when you try to create a TLS handle). 426automatically when you try to create a TLS handle): this module doesn't
427have a dependency on that module, so if your module requires it, you have
428to add the dependency yourself.
234 429
235For the TLS server side, use C<accept>, and for the TLS client side of a 430Unlike TCP, TLS has a server and client side: for the TLS server side, use
236connection, use C<connect> mode. 431C<accept>, and for the TLS client side of a connection, use C<connect>
432mode.
237 433
238You can also provide your own TLS connection object, but you have 434You can also provide your own TLS connection object, but you have
239to make sure that you call either C<Net::SSLeay::set_connect_state> 435to make sure that you call either C<Net::SSLeay::set_connect_state>
240or C<Net::SSLeay::set_accept_state> on it before you pass it to 436or C<Net::SSLeay::set_accept_state> on it before you pass it to
241AnyEvent::Handle. 437AnyEvent::Handle. Also, this module will take ownership of this connection
438object.
242 439
440At some future point, AnyEvent::Handle might switch to another TLS
441implementation, then the option to use your own session object will go
442away.
443
444B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
445passing in the wrong integer will lead to certain crash. This most often
446happens when one uses a stylish C<< tls => 1 >> and is surprised about the
447segmentation fault.
448
243See the C<starttls> method if you need to start TLS negotiation later. 449Use the C<< ->starttls >> method if you need to start TLS negotiation later.
244 450
245=item tls_ctx => $ssl_ctx 451=item tls_ctx => $anyevent_tls
246 452
247Use the given Net::SSLeay::CTX object to create the new TLS connection 453Use the given C<AnyEvent::TLS> object to create the new TLS connection
248(unless a connection object was specified directly). If this parameter is 454(unless a connection object was specified directly). If this
249missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 455parameter is missing (or C<undef>), then AnyEvent::Handle will use
456C<AnyEvent::Handle::TLS_CTX>.
457
458Instead of an object, you can also specify a hash reference with C<< key
459=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
460new TLS context object.
461
462=item on_starttls => $cb->($handle, $success[, $error_message])
463
464This callback will be invoked when the TLS/SSL handshake has finished. If
465C<$success> is true, then the TLS handshake succeeded, otherwise it failed
466(C<on_stoptls> will not be called in this case).
467
468The session in C<< $handle->{tls} >> can still be examined in this
469callback, even when the handshake was not successful.
470
471TLS handshake failures will not cause C<on_error> to be invoked when this
472callback is in effect, instead, the error message will be passed to C<on_starttls>.
473
474Without this callback, handshake failures lead to C<on_error> being
475called as usual.
476
477Note that you cannot just call C<starttls> again in this callback. If you
478need to do that, start an zero-second timer instead whose callback can
479then call C<< ->starttls >> again.
480
481=item on_stoptls => $cb->($handle)
482
483When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
484set, then it will be invoked after freeing the TLS session. If it is not,
485then a TLS shutdown condition will be treated like a normal EOF condition
486on the handle.
487
488The session in C<< $handle->{tls} >> can still be examined in this
489callback.
490
491This callback will only be called on TLS shutdowns, not when the
492underlying handle signals EOF.
250 493
251=item json => JSON or JSON::XS object 494=item json => JSON or JSON::XS object
252 495
253This is the json coder object used by the C<json> read and write types. 496This is the json coder object used by the C<json> read and write types.
254 497
255If you don't supply it, then AnyEvent::Handle will create and use a 498If you don't supply it, then AnyEvent::Handle will create and use a
256suitable one, which will write and expect UTF-8 encoded JSON texts. 499suitable one (on demand), which will write and expect UTF-8 encoded JSON
500texts.
257 501
258Note that you are responsible to depend on the JSON module if you want to 502Note that you are responsible to depend on the JSON module if you want to
259use this functionality, as AnyEvent does not have a dependency itself. 503use this functionality, as AnyEvent does not have a dependency itself.
260 504
261=item filter_r => $cb
262
263=item filter_w => $cb
264
265These exist, but are undocumented at this time.
266
267=back 505=back
268 506
269=cut 507=cut
270 508
271sub new { 509sub new {
272 my $class = shift; 510 my $class = shift;
273
274 my $self = bless { @_ }, $class; 511 my $self = bless { @_ }, $class;
275 512
276 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 513 if ($self->{fh}) {
514 $self->_start;
515 return unless $self->{fh}; # could be gone by now
516
517 } elsif ($self->{connect}) {
518 require AnyEvent::Socket;
519
520 $self->{peername} = $self->{connect}[0]
521 unless exists $self->{peername};
522
523 $self->{_skip_drain_rbuf} = 1;
524
525 {
526 Scalar::Util::weaken (my $self = $self);
527
528 $self->{_connect} =
529 AnyEvent::Socket::tcp_connect (
530 $self->{connect}[0],
531 $self->{connect}[1],
532 sub {
533 my ($fh, $host, $port, $retry) = @_;
534
535 delete $self->{_connect}; # no longer needed
536
537 if ($fh) {
538 $self->{fh} = $fh;
539
540 delete $self->{_skip_drain_rbuf};
541 $self->_start;
542
543 $self->{on_connect}
544 and $self->{on_connect}($self, $host, $port, sub {
545 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
546 $self->{_skip_drain_rbuf} = 1;
547 &$retry;
548 });
549
550 } else {
551 if ($self->{on_connect_error}) {
552 $self->{on_connect_error}($self, "$!");
553 $self->destroy if $self;
554 } else {
555 $self->_error ($!, 1);
556 }
557 }
558 },
559 sub {
560 local $self->{fh} = $_[0];
561
562 $self->{on_prepare}
563 ? $self->{on_prepare}->($self)
564 : ()
565 }
566 );
567 }
568
569 } else {
570 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
571 }
572
573 $self
574}
575
576sub _start {
577 my ($self) = @_;
578
579 # too many clueless people try to use udp and similar sockets
580 # with AnyEvent::Handle, do them a favour.
581 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
582 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
583 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
277 584
278 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 585 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
279 586
280 if ($self->{tls}) { 587 $self->{_activity} =
281 require Net::SSLeay; 588 $self->{_ractivity} =
589 $self->{_wactivity} = AE::now;
590
591 $self->{read_size} ||= 2048;
592 $self->{max_read_size} = $self->{read_size}
593 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
594
595 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
596 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
597 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
598
599 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
600 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
601
602 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
603
282 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 604 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
283 } 605 if $self->{tls};
284 606
285 $self->{_activity} = AnyEvent->now;
286 $self->_timeout;
287
288 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 607 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
289 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
290 608
291 $self->start_read 609 $self->start_read
292 if $self->{on_read}; 610 if $self->{on_read} || @{ $self->{_queue} };
293 611
294 $self 612 $self->_drain_wbuf;
295}
296
297sub _shutdown {
298 my ($self) = @_;
299
300 delete $self->{_tw};
301 delete $self->{_rw};
302 delete $self->{_ww};
303 delete $self->{fh};
304
305 $self->stoptls;
306
307 delete $self->{on_read};
308 delete $self->{_queue};
309} 613}
310 614
311sub _error { 615sub _error {
312 my ($self, $errno, $fatal) = @_; 616 my ($self, $errno, $fatal, $message) = @_;
313
314 $self->_shutdown
315 if $fatal;
316 617
317 $! = $errno; 618 $! = $errno;
619 $message ||= "$!";
318 620
319 if ($self->{on_error}) { 621 if ($self->{on_error}) {
320 $self->{on_error}($self, $fatal); 622 $self->{on_error}($self, $fatal, $message);
321 } else { 623 $self->destroy if $fatal;
624 } elsif ($self->{fh} || $self->{connect}) {
625 $self->destroy;
322 Carp::croak "AnyEvent::Handle uncaught error: $!"; 626 Carp::croak "AnyEvent::Handle uncaught error: $message";
323 } 627 }
324} 628}
325 629
326=item $fh = $handle->fh 630=item $fh = $handle->fh
327 631
328This method returns the file handle of the L<AnyEvent::Handle> object. 632This method returns the file handle used to create the L<AnyEvent::Handle> object.
329 633
330=cut 634=cut
331 635
332sub fh { $_[0]{fh} } 636sub fh { $_[0]{fh} }
333 637
351 $_[0]{on_eof} = $_[1]; 655 $_[0]{on_eof} = $_[1];
352} 656}
353 657
354=item $handle->on_timeout ($cb) 658=item $handle->on_timeout ($cb)
355 659
356Replace the current C<on_timeout> callback, or disables the callback 660=item $handle->on_rtimeout ($cb)
357(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
358argument.
359 661
360=cut 662=item $handle->on_wtimeout ($cb)
361 663
362sub on_timeout { 664Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
363 $_[0]{on_timeout} = $_[1]; 665callback, or disables the callback (but not the timeout) if C<$cb> =
364} 666C<undef>. See the C<timeout> constructor argument and method.
667
668=cut
669
670# see below
365 671
366=item $handle->autocork ($boolean) 672=item $handle->autocork ($boolean)
367 673
368Enables or disables the current autocork behaviour (see C<autocork> 674Enables or disables the current autocork behaviour (see C<autocork>
369constructor argument). 675constructor argument). Changes will only take effect on the next write.
370 676
371=cut 677=cut
678
679sub autocork {
680 $_[0]{autocork} = $_[1];
681}
372 682
373=item $handle->no_delay ($boolean) 683=item $handle->no_delay ($boolean)
374 684
375Enables or disables the C<no_delay> setting (see constructor argument of 685Enables or disables the C<no_delay> setting (see constructor argument of
376the same name for details). 686the same name for details).
378=cut 688=cut
379 689
380sub no_delay { 690sub no_delay {
381 $_[0]{no_delay} = $_[1]; 691 $_[0]{no_delay} = $_[1];
382 692
693 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
694 if $_[0]{fh};
695}
696
697=item $handle->keepalive ($boolean)
698
699Enables or disables the C<keepalive> setting (see constructor argument of
700the same name for details).
701
702=cut
703
704sub keepalive {
705 $_[0]{keepalive} = $_[1];
706
383 eval { 707 eval {
384 local $SIG{__DIE__}; 708 local $SIG{__DIE__};
385 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]; 709 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
710 if $_[0]{fh};
386 }; 711 };
387} 712}
388 713
714=item $handle->oobinline ($boolean)
715
716Enables or disables the C<oobinline> setting (see constructor argument of
717the same name for details).
718
719=cut
720
721sub oobinline {
722 $_[0]{oobinline} = $_[1];
723
724 eval {
725 local $SIG{__DIE__};
726 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
727 if $_[0]{fh};
728 };
729}
730
731=item $handle->keepalive ($boolean)
732
733Enables or disables the C<keepalive> setting (see constructor argument of
734the same name for details).
735
736=cut
737
738sub keepalive {
739 $_[0]{keepalive} = $_[1];
740
741 eval {
742 local $SIG{__DIE__};
743 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
744 if $_[0]{fh};
745 };
746}
747
748=item $handle->on_starttls ($cb)
749
750Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
751
752=cut
753
754sub on_starttls {
755 $_[0]{on_starttls} = $_[1];
756}
757
758=item $handle->on_stoptls ($cb)
759
760Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
761
762=cut
763
764sub on_stoptls {
765 $_[0]{on_stoptls} = $_[1];
766}
767
768=item $handle->rbuf_max ($max_octets)
769
770Configures the C<rbuf_max> setting (C<undef> disables it).
771
772=item $handle->wbuf_max ($max_octets)
773
774Configures the C<wbuf_max> setting (C<undef> disables it).
775
776=cut
777
778sub rbuf_max {
779 $_[0]{rbuf_max} = $_[1];
780}
781
782sub wbuf_max {
783 $_[0]{wbuf_max} = $_[1];
784}
785
389############################################################################# 786#############################################################################
390 787
391=item $handle->timeout ($seconds) 788=item $handle->timeout ($seconds)
392 789
790=item $handle->rtimeout ($seconds)
791
792=item $handle->wtimeout ($seconds)
793
393Configures (or disables) the inactivity timeout. 794Configures (or disables) the inactivity timeout.
394 795
395=cut 796The timeout will be checked instantly, so this method might destroy the
797handle before it returns.
396 798
397sub timeout { 799=item $handle->timeout_reset
800
801=item $handle->rtimeout_reset
802
803=item $handle->wtimeout_reset
804
805Reset the activity timeout, as if data was received or sent.
806
807These methods are cheap to call.
808
809=cut
810
811for my $dir ("", "r", "w") {
812 my $timeout = "${dir}timeout";
813 my $tw = "_${dir}tw";
814 my $on_timeout = "on_${dir}timeout";
815 my $activity = "_${dir}activity";
816 my $cb;
817
818 *$on_timeout = sub {
819 $_[0]{$on_timeout} = $_[1];
820 };
821
822 *$timeout = sub {
398 my ($self, $timeout) = @_; 823 my ($self, $new_value) = @_;
399 824
825 $new_value >= 0
826 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
827
400 $self->{timeout} = $timeout; 828 $self->{$timeout} = $new_value;
401 $self->_timeout; 829 delete $self->{$tw}; &$cb;
402} 830 };
403 831
832 *{"${dir}timeout_reset"} = sub {
833 $_[0]{$activity} = AE::now;
834 };
835
836 # main workhorse:
404# reset the timeout watcher, as neccessary 837 # reset the timeout watcher, as neccessary
405# also check for time-outs 838 # also check for time-outs
406sub _timeout { 839 $cb = sub {
407 my ($self) = @_; 840 my ($self) = @_;
408 841
409 if ($self->{timeout}) { 842 if ($self->{$timeout} && $self->{fh}) {
410 my $NOW = AnyEvent->now; 843 my $NOW = AE::now;
411 844
412 # when would the timeout trigger? 845 # when would the timeout trigger?
413 my $after = $self->{_activity} + $self->{timeout} - $NOW; 846 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
414 847
415 # now or in the past already? 848 # now or in the past already?
416 if ($after <= 0) { 849 if ($after <= 0) {
417 $self->{_activity} = $NOW; 850 $self->{$activity} = $NOW;
418 851
419 if ($self->{on_timeout}) { 852 if ($self->{$on_timeout}) {
420 $self->{on_timeout}($self); 853 $self->{$on_timeout}($self);
421 } else { 854 } else {
422 $self->_error (&Errno::ETIMEDOUT); 855 $self->_error (Errno::ETIMEDOUT);
856 }
857
858 # callback could have changed timeout value, optimise
859 return unless $self->{$timeout};
860
861 # calculate new after
862 $after = $self->{$timeout};
423 } 863 }
424 864
425 # callback could have changed timeout value, optimise 865 Scalar::Util::weaken $self;
426 return unless $self->{timeout}; 866 return unless $self; # ->error could have destroyed $self
427 867
428 # calculate new after 868 $self->{$tw} ||= AE::timer $after, 0, sub {
429 $after = $self->{timeout}; 869 delete $self->{$tw};
870 $cb->($self);
871 };
872 } else {
873 delete $self->{$tw};
430 } 874 }
431
432 Scalar::Util::weaken $self;
433 return unless $self; # ->error could have destroyed $self
434
435 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
436 delete $self->{_tw};
437 $self->_timeout;
438 });
439 } else {
440 delete $self->{_tw};
441 } 875 }
442} 876}
443 877
444############################################################################# 878#############################################################################
445 879
452 886
453The write queue is very simple: you can add data to its end, and 887The write queue is very simple: you can add data to its end, and
454AnyEvent::Handle will automatically try to get rid of it for you. 888AnyEvent::Handle will automatically try to get rid of it for you.
455 889
456When data could be written and the write buffer is shorter then the low 890When data could be written and the write buffer is shorter then the low
457water mark, the C<on_drain> callback will be invoked. 891water mark, the C<on_drain> callback will be invoked once.
458 892
459=over 4 893=over 4
460 894
461=item $handle->on_drain ($cb) 895=item $handle->on_drain ($cb)
462 896
463Sets the C<on_drain> callback or clears it (see the description of 897Sets the C<on_drain> callback or clears it (see the description of
464C<on_drain> in the constructor). 898C<on_drain> in the constructor).
465 899
900This method may invoke callbacks (and therefore the handle might be
901destroyed after it returns).
902
466=cut 903=cut
467 904
468sub on_drain { 905sub on_drain {
469 my ($self, $cb) = @_; 906 my ($self, $cb) = @_;
470 907
471 $self->{on_drain} = $cb; 908 $self->{on_drain} = $cb;
472 909
473 $cb->($self) 910 $cb->($self)
474 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 911 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
475} 912}
476 913
477=item $handle->push_write ($data) 914=item $handle->push_write ($data)
478 915
479Queues the given scalar to be written. You can push as much data as you 916Queues the given scalar to be written. You can push as much data as
480want (only limited by the available memory), as C<AnyEvent::Handle> 917you want (only limited by the available memory and C<wbuf_max>), as
481buffers it independently of the kernel. 918C<AnyEvent::Handle> buffers it independently of the kernel.
919
920This method may invoke callbacks (and therefore the handle might be
921destroyed after it returns).
482 922
483=cut 923=cut
484 924
485sub _drain_wbuf { 925sub _drain_wbuf {
486 my ($self) = @_; 926 my ($self) = @_;
490 Scalar::Util::weaken $self; 930 Scalar::Util::weaken $self;
491 931
492 my $cb = sub { 932 my $cb = sub {
493 my $len = syswrite $self->{fh}, $self->{wbuf}; 933 my $len = syswrite $self->{fh}, $self->{wbuf};
494 934
495 if ($len >= 0) { 935 if (defined $len) {
496 substr $self->{wbuf}, 0, $len, ""; 936 substr $self->{wbuf}, 0, $len, "";
497 937
498 $self->{_activity} = AnyEvent->now; 938 $self->{_activity} = $self->{_wactivity} = AE::now;
499 939
500 $self->{on_drain}($self) 940 $self->{on_drain}($self)
501 if $self->{low_water_mark} >= length $self->{wbuf} 941 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
502 && $self->{on_drain}; 942 && $self->{on_drain};
503 943
504 delete $self->{_ww} unless length $self->{wbuf}; 944 delete $self->{_ww} unless length $self->{wbuf};
505 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 945 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
506 $self->_error ($!, 1); 946 $self->_error ($!, 1);
509 949
510 # try to write data immediately 950 # try to write data immediately
511 $cb->() unless $self->{autocork}; 951 $cb->() unless $self->{autocork};
512 952
513 # if still data left in wbuf, we need to poll 953 # if still data left in wbuf, we need to poll
514 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 954 $self->{_ww} = AE::io $self->{fh}, 1, $cb
515 if length $self->{wbuf}; 955 if length $self->{wbuf};
956
957 if (
958 defined $self->{wbuf_max}
959 && $self->{wbuf_max} < length $self->{wbuf}
960 ) {
961 $self->_error (Errno::ENOSPC, 1), return;
962 }
516 }; 963 };
517} 964}
518 965
519our %WH; 966our %WH;
520 967
968# deprecated
521sub register_write_type($$) { 969sub register_write_type($$) {
522 $WH{$_[0]} = $_[1]; 970 $WH{$_[0]} = $_[1];
523} 971}
524 972
525sub push_write { 973sub push_write {
526 my $self = shift; 974 my $self = shift;
527 975
528 if (@_ > 1) { 976 if (@_ > 1) {
529 my $type = shift; 977 my $type = shift;
530 978
979 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
531 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 980 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
532 ->($self, @_); 981 ->($self, @_);
533 } 982 }
534 983
984 # we downgrade here to avoid hard-to-track-down bugs,
985 # and diagnose the problem earlier and better.
986
535 if ($self->{filter_w}) { 987 if ($self->{tls}) {
536 $self->{filter_w}($self, \$_[0]); 988 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
989 &_dotls ($self) if $self->{fh};
537 } else { 990 } else {
538 $self->{wbuf} .= $_[0]; 991 utf8::downgrade $self->{wbuf} .= $_[0];
539 $self->_drain_wbuf; 992 $self->_drain_wbuf if $self->{fh};
540 } 993 }
541} 994}
542 995
543=item $handle->push_write (type => @args) 996=item $handle->push_write (type => @args)
544 997
545Instead of formatting your data yourself, you can also let this module do 998Instead of formatting your data yourself, you can also let this module
546the job by specifying a type and type-specific arguments. 999do the job by specifying a type and type-specific arguments. You
1000can also specify the (fully qualified) name of a package, in which
1001case AnyEvent tries to load the package and then expects to find the
1002C<anyevent_write_type> function inside (see "custom write types", below).
547 1003
548Predefined types are (if you have ideas for additional types, feel free to 1004Predefined types are (if you have ideas for additional types, feel free to
549drop by and tell us): 1005drop by and tell us):
550 1006
551=over 4 1007=over 4
558=cut 1014=cut
559 1015
560register_write_type netstring => sub { 1016register_write_type netstring => sub {
561 my ($self, $string) = @_; 1017 my ($self, $string) = @_;
562 1018
563 sprintf "%d:%s,", (length $string), $string 1019 (length $string) . ":$string,"
564}; 1020};
565 1021
566=item packstring => $format, $data 1022=item packstring => $format, $data
567 1023
568An octet string prefixed with an encoded length. The encoding C<$format> 1024An octet string prefixed with an encoded length. The encoding C<$format>
608Other languages could read single lines terminated by a newline and pass 1064Other languages could read single lines terminated by a newline and pass
609this line into their JSON decoder of choice. 1065this line into their JSON decoder of choice.
610 1066
611=cut 1067=cut
612 1068
1069sub json_coder() {
1070 eval { require JSON::XS; JSON::XS->new->utf8 }
1071 || do { require JSON; JSON->new->utf8 }
1072}
1073
613register_write_type json => sub { 1074register_write_type json => sub {
614 my ($self, $ref) = @_; 1075 my ($self, $ref) = @_;
615 1076
616 require JSON; 1077 my $json = $self->{json} ||= json_coder;
617 1078
618 $self->{json} ? $self->{json}->encode ($ref) 1079 $json->encode ($ref)
619 : JSON::encode_json ($ref)
620}; 1080};
621 1081
622=item storable => $reference 1082=item storable => $reference
623 1083
624Freezes the given reference using L<Storable> and writes it to the 1084Freezes the given reference using L<Storable> and writes it to the
627=cut 1087=cut
628 1088
629register_write_type storable => sub { 1089register_write_type storable => sub {
630 my ($self, $ref) = @_; 1090 my ($self, $ref) = @_;
631 1091
632 require Storable; 1092 require Storable unless $Storable::VERSION;
633 1093
634 pack "w/a*", Storable::nfreeze ($ref) 1094 pack "w/a*", Storable::nfreeze ($ref)
635}; 1095};
636 1096
637=back 1097=back
638 1098
639=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1099=item $handle->push_shutdown
640 1100
641This function (not method) lets you add your own types to C<push_write>. 1101Sometimes you know you want to close the socket after writing your data
1102before it was actually written. One way to do that is to replace your
1103C<on_drain> handler by a callback that shuts down the socket (and set
1104C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1105replaces the C<on_drain> callback with:
1106
1107 sub { shutdown $_[0]{fh}, 1 }
1108
1109This simply shuts down the write side and signals an EOF condition to the
1110the peer.
1111
1112You can rely on the normal read queue and C<on_eof> handling
1113afterwards. This is the cleanest way to close a connection.
1114
1115This method may invoke callbacks (and therefore the handle might be
1116destroyed after it returns).
1117
1118=cut
1119
1120sub push_shutdown {
1121 my ($self) = @_;
1122
1123 delete $self->{low_water_mark};
1124 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1125}
1126
1127=item custom write types - Package::anyevent_write_type $handle, @args
1128
1129Instead of one of the predefined types, you can also specify the name of
1130a package. AnyEvent will try to load the package and then expects to find
1131a function named C<anyevent_write_type> inside. If it isn't found, it
1132progressively tries to load the parent package until it either finds the
1133function (good) or runs out of packages (bad).
1134
642Whenever the given C<type> is used, C<push_write> will invoke the code 1135Whenever the given C<type> is used, C<push_write> will the function with
643reference with the handle object and the remaining arguments. 1136the handle object and the remaining arguments.
644 1137
645The code reference is supposed to return a single octet string that will 1138The function is supposed to return a single octet string that will be
646be appended to the write buffer. 1139appended to the write buffer, so you can mentally treat this function as a
1140"arguments to on-the-wire-format" converter.
647 1141
648Note that this is a function, and all types registered this way will be 1142Example: implement a custom write type C<join> that joins the remaining
649global, so try to use unique names. 1143arguments using the first one.
1144
1145 $handle->push_write (My::Type => " ", 1,2,3);
1146
1147 # uses the following package, which can be defined in the "My::Type" or in
1148 # the "My" modules to be auto-loaded, or just about anywhere when the
1149 # My::Type::anyevent_write_type is defined before invoking it.
1150
1151 package My::Type;
1152
1153 sub anyevent_write_type {
1154 my ($handle, $delim, @args) = @_;
1155
1156 join $delim, @args
1157 }
650 1158
651=cut 1159=cut
652 1160
653############################################################################# 1161#############################################################################
654 1162
663ways, the "simple" way, using only C<on_read> and the "complex" way, using 1171ways, the "simple" way, using only C<on_read> and the "complex" way, using
664a queue. 1172a queue.
665 1173
666In the simple case, you just install an C<on_read> callback and whenever 1174In the simple case, you just install an C<on_read> callback and whenever
667new data arrives, it will be called. You can then remove some data (if 1175new data arrives, it will be called. You can then remove some data (if
668enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1176enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
669leave the data there if you want to accumulate more (e.g. when only a 1177leave the data there if you want to accumulate more (e.g. when only a
670partial message has been received so far). 1178partial message has been received so far), or change the read queue with
1179e.g. C<push_read>.
671 1180
672In the more complex case, you want to queue multiple callbacks. In this 1181In the more complex case, you want to queue multiple callbacks. In this
673case, AnyEvent::Handle will call the first queued callback each time new 1182case, AnyEvent::Handle will call the first queued callback each time new
674data arrives (also the first time it is queued) and removes it when it has 1183data arrives (also the first time it is queued) and remove it when it has
675done its job (see C<push_read>, below). 1184done its job (see C<push_read>, below).
676 1185
677This way you can, for example, push three line-reads, followed by reading 1186This way you can, for example, push three line-reads, followed by reading
678a chunk of data, and AnyEvent::Handle will execute them in order. 1187a chunk of data, and AnyEvent::Handle will execute them in order.
679 1188
736=cut 1245=cut
737 1246
738sub _drain_rbuf { 1247sub _drain_rbuf {
739 my ($self) = @_; 1248 my ($self) = @_;
740 1249
1250 # avoid recursion
1251 return if $self->{_skip_drain_rbuf};
741 local $self->{_in_drain} = 1; 1252 local $self->{_skip_drain_rbuf} = 1;
742
743 if (
744 defined $self->{rbuf_max}
745 && $self->{rbuf_max} < length $self->{rbuf}
746 ) {
747 $self->_error (&Errno::ENOSPC, 1), return;
748 }
749 1253
750 while () { 1254 while () {
1255 # we need to use a separate tls read buffer, as we must not receive data while
1256 # we are draining the buffer, and this can only happen with TLS.
1257 $self->{rbuf} .= delete $self->{_tls_rbuf}
1258 if exists $self->{_tls_rbuf};
1259
751 my $len = length $self->{rbuf}; 1260 my $len = length $self->{rbuf};
752 1261
753 if (my $cb = shift @{ $self->{_queue} }) { 1262 if (my $cb = shift @{ $self->{_queue} }) {
754 unless ($cb->($self)) { 1263 unless ($cb->($self)) {
755 if ($self->{_eof}) { 1264 # no progress can be made
756 # no progress can be made (not enough data and no data forthcoming) 1265 # (not enough data and no data forthcoming)
757 $self->_error (&Errno::EPIPE, 1), return; 1266 $self->_error (Errno::EPIPE, 1), return
758 } 1267 if $self->{_eof};
759 1268
760 unshift @{ $self->{_queue} }, $cb; 1269 unshift @{ $self->{_queue} }, $cb;
761 last; 1270 last;
762 } 1271 }
763 } elsif ($self->{on_read}) { 1272 } elsif ($self->{on_read}) {
770 && !@{ $self->{_queue} } # and the queue is still empty 1279 && !@{ $self->{_queue} } # and the queue is still empty
771 && $self->{on_read} # but we still have on_read 1280 && $self->{on_read} # but we still have on_read
772 ) { 1281 ) {
773 # no further data will arrive 1282 # no further data will arrive
774 # so no progress can be made 1283 # so no progress can be made
775 $self->_error (&Errno::EPIPE, 1), return 1284 $self->_error (Errno::EPIPE, 1), return
776 if $self->{_eof}; 1285 if $self->{_eof};
777 1286
778 last; # more data might arrive 1287 last; # more data might arrive
779 } 1288 }
780 } else { 1289 } else {
781 # read side becomes idle 1290 # read side becomes idle
782 delete $self->{_rw}; 1291 delete $self->{_rw} unless $self->{tls};
783 last; 1292 last;
784 } 1293 }
785 } 1294 }
786 1295
787 if ($self->{_eof}) { 1296 if ($self->{_eof}) {
788 if ($self->{on_eof}) { 1297 $self->{on_eof}
789 $self->{on_eof}($self) 1298 ? $self->{on_eof}($self)
790 } else { 1299 : $self->_error (0, 1, "Unexpected end-of-file");
791 $self->_error (0, 1); 1300
792 } 1301 return;
1302 }
1303
1304 if (
1305 defined $self->{rbuf_max}
1306 && $self->{rbuf_max} < length $self->{rbuf}
1307 ) {
1308 $self->_error (Errno::ENOSPC, 1), return;
793 } 1309 }
794 1310
795 # may need to restart read watcher 1311 # may need to restart read watcher
796 unless ($self->{_rw}) { 1312 unless ($self->{_rw}) {
797 $self->start_read 1313 $self->start_read
803 1319
804This replaces the currently set C<on_read> callback, or clears it (when 1320This replaces the currently set C<on_read> callback, or clears it (when
805the new callback is C<undef>). See the description of C<on_read> in the 1321the new callback is C<undef>). See the description of C<on_read> in the
806constructor. 1322constructor.
807 1323
1324This method may invoke callbacks (and therefore the handle might be
1325destroyed after it returns).
1326
808=cut 1327=cut
809 1328
810sub on_read { 1329sub on_read {
811 my ($self, $cb) = @_; 1330 my ($self, $cb) = @_;
812 1331
813 $self->{on_read} = $cb; 1332 $self->{on_read} = $cb;
814 $self->_drain_rbuf if $cb && !$self->{_in_drain}; 1333 $self->_drain_rbuf if $cb;
815} 1334}
816 1335
817=item $handle->rbuf 1336=item $handle->rbuf
818 1337
819Returns the read buffer (as a modifiable lvalue). 1338Returns the read buffer (as a modifiable lvalue). You can also access the
1339read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1340much faster, and no less clean).
820 1341
821You can access the read buffer directly as the C<< ->{rbuf} >> member, if 1342The only operation allowed on the read buffer (apart from looking at it)
822you want. 1343is removing data from its beginning. Otherwise modifying or appending to
1344it is not allowed and will lead to hard-to-track-down bugs.
823 1345
824NOTE: The read buffer should only be used or modified if the C<on_read>, 1346NOTE: The read buffer should only be used or modified in the C<on_read>
825C<push_read> or C<unshift_read> methods are used. The other read methods 1347callback or when C<push_read> or C<unshift_read> are used with a single
826automatically manage the read buffer. 1348callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1349will manage the read buffer on their own.
827 1350
828=cut 1351=cut
829 1352
830sub rbuf : lvalue { 1353sub rbuf : lvalue {
831 $_[0]{rbuf} 1354 $_[0]{rbuf}
848 1371
849If enough data was available, then the callback must remove all data it is 1372If enough data was available, then the callback must remove all data it is
850interested in (which can be none at all) and return a true value. After returning 1373interested in (which can be none at all) and return a true value. After returning
851true, it will be removed from the queue. 1374true, it will be removed from the queue.
852 1375
1376These methods may invoke callbacks (and therefore the handle might be
1377destroyed after it returns).
1378
853=cut 1379=cut
854 1380
855our %RH; 1381our %RH;
856 1382
857sub register_read_type($$) { 1383sub register_read_type($$) {
863 my $cb = pop; 1389 my $cb = pop;
864 1390
865 if (@_) { 1391 if (@_) {
866 my $type = shift; 1392 my $type = shift;
867 1393
1394 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
868 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1395 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
869 ->($self, $cb, @_); 1396 ->($self, $cb, @_);
870 } 1397 }
871 1398
872 push @{ $self->{_queue} }, $cb; 1399 push @{ $self->{_queue} }, $cb;
873 $self->_drain_rbuf unless $self->{_in_drain}; 1400 $self->_drain_rbuf;
874} 1401}
875 1402
876sub unshift_read { 1403sub unshift_read {
877 my $self = shift; 1404 my $self = shift;
878 my $cb = pop; 1405 my $cb = pop;
879 1406
880 if (@_) { 1407 if (@_) {
881 my $type = shift; 1408 my $type = shift;
882 1409
1410 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
883 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1411 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
884 ->($self, $cb, @_); 1412 ->($self, $cb, @_);
885 } 1413 }
886 1414
887
888 unshift @{ $self->{_queue} }, $cb; 1415 unshift @{ $self->{_queue} }, $cb;
889 $self->_drain_rbuf unless $self->{_in_drain}; 1416 $self->_drain_rbuf;
890} 1417}
891 1418
892=item $handle->push_read (type => @args, $cb) 1419=item $handle->push_read (type => @args, $cb)
893 1420
894=item $handle->unshift_read (type => @args, $cb) 1421=item $handle->unshift_read (type => @args, $cb)
895 1422
896Instead of providing a callback that parses the data itself you can chose 1423Instead of providing a callback that parses the data itself you can chose
897between a number of predefined parsing formats, for chunks of data, lines 1424between a number of predefined parsing formats, for chunks of data, lines
898etc. 1425etc. You can also specify the (fully qualified) name of a package, in
1426which case AnyEvent tries to load the package and then expects to find the
1427C<anyevent_read_type> function inside (see "custom read types", below).
899 1428
900Predefined types are (if you have ideas for additional types, feel free to 1429Predefined types are (if you have ideas for additional types, feel free to
901drop by and tell us): 1430drop by and tell us):
902 1431
903=over 4 1432=over 4
909data. 1438data.
910 1439
911Example: read 2 bytes. 1440Example: read 2 bytes.
912 1441
913 $handle->push_read (chunk => 2, sub { 1442 $handle->push_read (chunk => 2, sub {
914 warn "yay ", unpack "H*", $_[1]; 1443 say "yay " . unpack "H*", $_[1];
915 }); 1444 });
916 1445
917=cut 1446=cut
918 1447
919register_read_type chunk => sub { 1448register_read_type chunk => sub {
953 if (@_ < 3) { 1482 if (@_ < 3) {
954 # this is more than twice as fast as the generic code below 1483 # this is more than twice as fast as the generic code below
955 sub { 1484 sub {
956 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1485 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
957 1486
958 $cb->($_[0], $1, $2); 1487 $cb->($_[0], "$1", "$2");
959 1 1488 1
960 } 1489 }
961 } else { 1490 } else {
962 $eol = quotemeta $eol unless ref $eol; 1491 $eol = quotemeta $eol unless ref $eol;
963 $eol = qr|^(.*?)($eol)|s; 1492 $eol = qr|^(.*?)($eol)|s;
964 1493
965 sub { 1494 sub {
966 $_[0]{rbuf} =~ s/$eol// or return; 1495 $_[0]{rbuf} =~ s/$eol// or return;
967 1496
968 $cb->($_[0], $1, $2); 1497 $cb->($_[0], "$1", "$2");
969 1 1498 1
970 } 1499 }
971 } 1500 }
972}; 1501};
973 1502
995the receive buffer when neither C<$accept> nor C<$reject> match, 1524the receive buffer when neither C<$accept> nor C<$reject> match,
996and everything preceding and including the match will be accepted 1525and everything preceding and including the match will be accepted
997unconditionally. This is useful to skip large amounts of data that you 1526unconditionally. This is useful to skip large amounts of data that you
998know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1527know cannot be matched, so that the C<$accept> or C<$reject> regex do not
999have to start matching from the beginning. This is purely an optimisation 1528have to start matching from the beginning. This is purely an optimisation
1000and is usually worth only when you expect more than a few kilobytes. 1529and is usually worth it only when you expect more than a few kilobytes.
1001 1530
1002Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1531Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1003expect the header to be very large (it isn't in practise, but...), we use 1532expect the header to be very large (it isn't in practice, but...), we use
1004a skip regex to skip initial portions. The skip regex is tricky in that 1533a skip regex to skip initial portions. The skip regex is tricky in that
1005it only accepts something not ending in either \015 or \012, as these are 1534it only accepts something not ending in either \015 or \012, as these are
1006required for the accept regex. 1535required for the accept regex.
1007 1536
1008 $handle->push_read (regex => 1537 $handle->push_read (regex =>
1021 1550
1022 sub { 1551 sub {
1023 # accept 1552 # accept
1024 if ($$rbuf =~ $accept) { 1553 if ($$rbuf =~ $accept) {
1025 $data .= substr $$rbuf, 0, $+[0], ""; 1554 $data .= substr $$rbuf, 0, $+[0], "";
1026 $cb->($self, $data); 1555 $cb->($_[0], $data);
1027 return 1; 1556 return 1;
1028 } 1557 }
1029 1558
1030 # reject 1559 # reject
1031 if ($reject && $$rbuf =~ $reject) { 1560 if ($reject && $$rbuf =~ $reject) {
1032 $self->_error (&Errno::EBADMSG); 1561 $_[0]->_error (Errno::EBADMSG);
1033 } 1562 }
1034 1563
1035 # skip 1564 # skip
1036 if ($skip && $$rbuf =~ $skip) { 1565 if ($skip && $$rbuf =~ $skip) {
1037 $data .= substr $$rbuf, 0, $+[0], ""; 1566 $data .= substr $$rbuf, 0, $+[0], "";
1053 my ($self, $cb) = @_; 1582 my ($self, $cb) = @_;
1054 1583
1055 sub { 1584 sub {
1056 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1585 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1057 if ($_[0]{rbuf} =~ /[^0-9]/) { 1586 if ($_[0]{rbuf} =~ /[^0-9]/) {
1058 $self->_error (&Errno::EBADMSG); 1587 $_[0]->_error (Errno::EBADMSG);
1059 } 1588 }
1060 return; 1589 return;
1061 } 1590 }
1062 1591
1063 my $len = $1; 1592 my $len = $1;
1064 1593
1065 $self->unshift_read (chunk => $len, sub { 1594 $_[0]->unshift_read (chunk => $len, sub {
1066 my $string = $_[1]; 1595 my $string = $_[1];
1067 $_[0]->unshift_read (chunk => 1, sub { 1596 $_[0]->unshift_read (chunk => 1, sub {
1068 if ($_[1] eq ",") { 1597 if ($_[1] eq ",") {
1069 $cb->($_[0], $string); 1598 $cb->($_[0], $string);
1070 } else { 1599 } else {
1071 $self->_error (&Errno::EBADMSG); 1600 $_[0]->_error (Errno::EBADMSG);
1072 } 1601 }
1073 }); 1602 });
1074 }); 1603 });
1075 1604
1076 1 1605 1
1082An octet string prefixed with an encoded length. The encoding C<$format> 1611An octet string prefixed with an encoded length. The encoding C<$format>
1083uses the same format as a Perl C<pack> format, but must specify a single 1612uses the same format as a Perl C<pack> format, but must specify a single
1084integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an 1613integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1085optional C<!>, C<< < >> or C<< > >> modifier). 1614optional C<!>, C<< < >> or C<< > >> modifier).
1086 1615
1087DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>. 1616For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1617EPP uses a prefix of C<N> (4 octtes).
1088 1618
1089Example: read a block of data prefixed by its length in BER-encoded 1619Example: read a block of data prefixed by its length in BER-encoded
1090format (very efficient). 1620format (very efficient).
1091 1621
1092 $handle->push_read (packstring => "w", sub { 1622 $handle->push_read (packstring => "w", sub {
1122 } 1652 }
1123}; 1653};
1124 1654
1125=item json => $cb->($handle, $hash_or_arrayref) 1655=item json => $cb->($handle, $hash_or_arrayref)
1126 1656
1127Reads a JSON object or array, decodes it and passes it to the callback. 1657Reads a JSON object or array, decodes it and passes it to the
1658callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1128 1659
1129If a C<json> object was passed to the constructor, then that will be used 1660If a C<json> object was passed to the constructor, then that will be used
1130for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1661for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1131 1662
1132This read type uses the incremental parser available with JSON version 1663This read type uses the incremental parser available with JSON version
1141=cut 1672=cut
1142 1673
1143register_read_type json => sub { 1674register_read_type json => sub {
1144 my ($self, $cb) = @_; 1675 my ($self, $cb) = @_;
1145 1676
1146 require JSON; 1677 my $json = $self->{json} ||= json_coder;
1147 1678
1148 my $data; 1679 my $data;
1149 my $rbuf = \$self->{rbuf}; 1680 my $rbuf = \$self->{rbuf};
1150 1681
1151 my $json = $self->{json} ||= JSON->new->utf8;
1152
1153 sub { 1682 sub {
1154 my $ref = $json->incr_parse ($self->{rbuf}); 1683 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1155 1684
1156 if ($ref) { 1685 if ($ref) {
1157 $self->{rbuf} = $json->incr_text; 1686 $_[0]{rbuf} = $json->incr_text;
1158 $json->incr_text = ""; 1687 $json->incr_text = "";
1159 $cb->($self, $ref); 1688 $cb->($_[0], $ref);
1160 1689
1161 1 1690 1
1691 } elsif ($@) {
1692 # error case
1693 $json->incr_skip;
1694
1695 $_[0]{rbuf} = $json->incr_text;
1696 $json->incr_text = "";
1697
1698 $_[0]->_error (Errno::EBADMSG);
1699
1700 ()
1162 } else { 1701 } else {
1163 $self->{rbuf} = ""; 1702 $_[0]{rbuf} = "";
1703
1164 () 1704 ()
1165 } 1705 }
1166 } 1706 }
1167}; 1707};
1168 1708
1177=cut 1717=cut
1178 1718
1179register_read_type storable => sub { 1719register_read_type storable => sub {
1180 my ($self, $cb) = @_; 1720 my ($self, $cb) = @_;
1181 1721
1182 require Storable; 1722 require Storable unless $Storable::VERSION;
1183 1723
1184 sub { 1724 sub {
1185 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1725 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1186 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1726 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1187 or return; 1727 or return;
1190 1730
1191 # bypass unshift if we already have the remaining chunk 1731 # bypass unshift if we already have the remaining chunk
1192 if ($format + $len <= length $_[0]{rbuf}) { 1732 if ($format + $len <= length $_[0]{rbuf}) {
1193 my $data = substr $_[0]{rbuf}, $format, $len; 1733 my $data = substr $_[0]{rbuf}, $format, $len;
1194 substr $_[0]{rbuf}, 0, $format + $len, ""; 1734 substr $_[0]{rbuf}, 0, $format + $len, "";
1735
1195 $cb->($_[0], Storable::thaw ($data)); 1736 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1737 or return $_[0]->_error (Errno::EBADMSG);
1196 } else { 1738 } else {
1197 # remove prefix 1739 # remove prefix
1198 substr $_[0]{rbuf}, 0, $format, ""; 1740 substr $_[0]{rbuf}, 0, $format, "";
1199 1741
1200 # read remaining chunk 1742 # read remaining chunk
1201 $_[0]->unshift_read (chunk => $len, sub { 1743 $_[0]->unshift_read (chunk => $len, sub {
1202 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1744 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1203 $cb->($_[0], $ref);
1204 } else {
1205 $self->_error (&Errno::EBADMSG); 1745 or $_[0]->_error (Errno::EBADMSG);
1206 }
1207 }); 1746 });
1208 } 1747 }
1209 1748
1210 1 1749 1
1211 } 1750 }
1212}; 1751};
1213 1752
1214=back 1753=back
1215 1754
1216=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1755=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1217 1756
1218This function (not method) lets you add your own types to C<push_read>. 1757Instead of one of the predefined types, you can also specify the name
1758of a package. AnyEvent will try to load the package and then expects to
1759find a function named C<anyevent_read_type> inside. If it isn't found, it
1760progressively tries to load the parent package until it either finds the
1761function (good) or runs out of packages (bad).
1219 1762
1220Whenever the given C<type> is used, C<push_read> will invoke the code 1763Whenever this type is used, C<push_read> will invoke the function with the
1221reference with the handle object, the callback and the remaining 1764handle object, the original callback and the remaining arguments.
1222arguments.
1223 1765
1224The code reference is supposed to return a callback (usually a closure) 1766The function is supposed to return a callback (usually a closure) that
1225that works as a plain read callback (see C<< ->push_read ($cb) >>). 1767works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1768mentally treat the function as a "configurable read type to read callback"
1769converter.
1226 1770
1227It should invoke the passed callback when it is done reading (remember to 1771It should invoke the original callback when it is done reading (remember
1228pass C<$handle> as first argument as all other callbacks do that). 1772to pass C<$handle> as first argument as all other callbacks do that,
1773although there is no strict requirement on this).
1229 1774
1230Note that this is a function, and all types registered this way will be
1231global, so try to use unique names.
1232
1233For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1775For examples, see the source of this module (F<perldoc -m
1234search for C<register_read_type>)). 1776AnyEvent::Handle>, search for C<register_read_type>)).
1235 1777
1236=item $handle->stop_read 1778=item $handle->stop_read
1237 1779
1238=item $handle->start_read 1780=item $handle->start_read
1239 1781
1245Note that AnyEvent::Handle will automatically C<start_read> for you when 1787Note that AnyEvent::Handle will automatically C<start_read> for you when
1246you change the C<on_read> callback or push/unshift a read callback, and it 1788you change the C<on_read> callback or push/unshift a read callback, and it
1247will automatically C<stop_read> for you when neither C<on_read> is set nor 1789will automatically C<stop_read> for you when neither C<on_read> is set nor
1248there are any read requests in the queue. 1790there are any read requests in the queue.
1249 1791
1792In older versions of this module (<= 5.3), these methods had no effect,
1793as TLS does not support half-duplex connections. In current versions they
1794work as expected, as this behaviour is required to avoid certain resource
1795attacks, where the program would be forced to read (and buffer) arbitrary
1796amounts of data before being able to send some data. The drawback is that
1797some readings of the the SSL/TLS specifications basically require this
1798attack to be working, as SSL/TLS implementations might stall sending data
1799during a rehandshake.
1800
1801As a guideline, during the initial handshake, you should not stop reading,
1802and as a client, it might cause problems, depending on your application.
1803
1250=cut 1804=cut
1251 1805
1252sub stop_read { 1806sub stop_read {
1253 my ($self) = @_; 1807 my ($self) = @_;
1254 1808
1256} 1810}
1257 1811
1258sub start_read { 1812sub start_read {
1259 my ($self) = @_; 1813 my ($self) = @_;
1260 1814
1261 unless ($self->{_rw} || $self->{_eof}) { 1815 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1262 Scalar::Util::weaken $self; 1816 Scalar::Util::weaken $self;
1263 1817
1264 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1818 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1265 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1819 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1266 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1820 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1267 1821
1268 if ($len > 0) { 1822 if ($len > 0) {
1269 $self->{_activity} = AnyEvent->now; 1823 $self->{_activity} = $self->{_ractivity} = AE::now;
1270 1824
1271 $self->{filter_r} 1825 if ($self->{tls}) {
1272 ? $self->{filter_r}($self, $rbuf) 1826 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1273 : $self->{_in_drain} || $self->_drain_rbuf; 1827
1828 &_dotls ($self);
1829 } else {
1830 $self->_drain_rbuf;
1831 }
1832
1833 if ($len == $self->{read_size}) {
1834 $self->{read_size} *= 2;
1835 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1836 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1837 }
1274 1838
1275 } elsif (defined $len) { 1839 } elsif (defined $len) {
1276 delete $self->{_rw}; 1840 delete $self->{_rw};
1277 $self->{_eof} = 1; 1841 $self->{_eof} = 1;
1278 $self->_drain_rbuf unless $self->{_in_drain}; 1842 $self->_drain_rbuf;
1279 1843
1280 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1844 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1281 return $self->_error ($!, 1); 1845 return $self->_error ($!, 1);
1282 } 1846 }
1283 }); 1847 };
1284 } 1848 }
1285} 1849}
1286 1850
1851our $ERROR_SYSCALL;
1852our $ERROR_WANT_READ;
1853
1854sub _tls_error {
1855 my ($self, $err) = @_;
1856
1857 return $self->_error ($!, 1)
1858 if $err == Net::SSLeay::ERROR_SYSCALL ();
1859
1860 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1861
1862 # reduce error string to look less scary
1863 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1864
1865 if ($self->{_on_starttls}) {
1866 (delete $self->{_on_starttls})->($self, undef, $err);
1867 &_freetls;
1868 } else {
1869 &_freetls;
1870 $self->_error (Errno::EPROTO, 1, $err);
1871 }
1872}
1873
1874# poll the write BIO and send the data if applicable
1875# also decode read data if possible
1876# this is basiclaly our TLS state machine
1877# more efficient implementations are possible with openssl,
1878# but not with the buggy and incomplete Net::SSLeay.
1287sub _dotls { 1879sub _dotls {
1288 my ($self) = @_; 1880 my ($self) = @_;
1289 1881
1290 my $buf; 1882 my $tmp;
1291 1883
1292 if (length $self->{_tls_wbuf}) { 1884 if (length $self->{_tls_wbuf}) {
1293 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1885 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1294 substr $self->{_tls_wbuf}, 0, $len, ""; 1886 substr $self->{_tls_wbuf}, 0, $tmp, "";
1295 } 1887 }
1296 }
1297 1888
1889 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1890 return $self->_tls_error ($tmp)
1891 if $tmp != $ERROR_WANT_READ
1892 && ($tmp != $ERROR_SYSCALL || $!);
1893 }
1894
1895 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1896 unless (length $tmp) {
1897 $self->{_on_starttls}
1898 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1899 &_freetls;
1900
1901 if ($self->{on_stoptls}) {
1902 $self->{on_stoptls}($self);
1903 return;
1904 } else {
1905 # let's treat SSL-eof as we treat normal EOF
1906 delete $self->{_rw};
1907 $self->{_eof} = 1;
1908 }
1909 }
1910
1911 $self->{_tls_rbuf} .= $tmp;
1912 $self->_drain_rbuf;
1913 $self->{tls} or return; # tls session might have gone away in callback
1914 }
1915
1916 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1917 return $self->_tls_error ($tmp)
1918 if $tmp != $ERROR_WANT_READ
1919 && ($tmp != $ERROR_SYSCALL || $!);
1920
1298 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1921 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1299 $self->{wbuf} .= $buf; 1922 $self->{wbuf} .= $tmp;
1300 $self->_drain_wbuf; 1923 $self->_drain_wbuf;
1924 $self->{tls} or return; # tls session might have gone away in callback
1301 } 1925 }
1302 1926
1303 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { 1927 $self->{_on_starttls}
1304 if (length $buf) { 1928 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1305 $self->{rbuf} .= $buf; 1929 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1306 $self->_drain_rbuf unless $self->{_in_drain};
1307 } else {
1308 # let's treat SSL-eof as we treat normal EOF
1309 $self->{_eof} = 1;
1310 $self->_shutdown;
1311 return;
1312 }
1313 }
1314
1315 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1316
1317 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1318 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1319 return $self->_error ($!, 1);
1320 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1321 return $self->_error (&Errno::EIO, 1);
1322 }
1323
1324 # all others are fine for our purposes
1325 }
1326} 1930}
1327 1931
1328=item $handle->starttls ($tls[, $tls_ctx]) 1932=item $handle->starttls ($tls[, $tls_ctx])
1329 1933
1330Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1934Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1331object is created, you can also do that at a later time by calling 1935object is created, you can also do that at a later time by calling
1332C<starttls>. 1936C<starttls>.
1333 1937
1938Starting TLS is currently an asynchronous operation - when you push some
1939write data and then call C<< ->starttls >> then TLS negotiation will start
1940immediately, after which the queued write data is then sent.
1941
1334The first argument is the same as the C<tls> constructor argument (either 1942The first argument is the same as the C<tls> constructor argument (either
1335C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1943C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1336 1944
1337The second argument is the optional C<Net::SSLeay::CTX> object that is 1945The second argument is the optional C<AnyEvent::TLS> object that is used
1338used when AnyEvent::Handle has to create its own TLS connection object. 1946when AnyEvent::Handle has to create its own TLS connection object, or
1947a hash reference with C<< key => value >> pairs that will be used to
1948construct a new context.
1339 1949
1340The TLS connection object will end up in C<< $handle->{tls} >> after this 1950The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1341call and can be used or changed to your liking. Note that the handshake 1951context in C<< $handle->{tls_ctx} >> after this call and can be used or
1342might have already started when this function returns. 1952changed to your liking. Note that the handshake might have already started
1953when this function returns.
1343 1954
1955Due to bugs in OpenSSL, it might or might not be possible to do multiple
1956handshakes on the same stream. It is best to not attempt to use the
1957stream after stopping TLS.
1958
1959This method may invoke callbacks (and therefore the handle might be
1960destroyed after it returns).
1961
1344=cut 1962=cut
1963
1964our %TLS_CACHE; #TODO not yet documented, should we?
1345 1965
1346sub starttls { 1966sub starttls {
1347 my ($self, $ssl, $ctx) = @_; 1967 my ($self, $tls, $ctx) = @_;
1348 1968
1349 $self->stoptls; 1969 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1970 if $self->{tls};
1350 1971
1351 if ($ssl eq "accept") { 1972 $self->{tls} = $tls;
1352 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1973 $self->{tls_ctx} = $ctx if @_ > 2;
1353 Net::SSLeay::set_accept_state ($ssl); 1974
1354 } elsif ($ssl eq "connect") { 1975 return unless $self->{fh};
1355 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1976
1356 Net::SSLeay::set_connect_state ($ssl); 1977 require Net::SSLeay;
1978
1979 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1980 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1981
1982 $tls = delete $self->{tls};
1983 $ctx = $self->{tls_ctx};
1984
1985 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1986
1987 if ("HASH" eq ref $ctx) {
1988 require AnyEvent::TLS;
1989
1990 if ($ctx->{cache}) {
1991 my $key = $ctx+0;
1992 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1993 } else {
1994 $ctx = new AnyEvent::TLS %$ctx;
1995 }
1996 }
1357 } 1997
1358 1998 $self->{tls_ctx} = $ctx || TLS_CTX ();
1359 $self->{tls} = $ssl; 1999 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1360 2000
1361 # basically, this is deep magic (because SSL_read should have the same issues) 2001 # basically, this is deep magic (because SSL_read should have the same issues)
1362 # but the openssl maintainers basically said: "trust us, it just works". 2002 # but the openssl maintainers basically said: "trust us, it just works".
1363 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2003 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1364 # and mismaintained ssleay-module doesn't even offer them). 2004 # and mismaintained ssleay-module doesn't even offer them).
1365 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 2005 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
2006 #
2007 # in short: this is a mess.
2008 #
2009 # note that we do not try to keep the length constant between writes as we are required to do.
2010 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
2011 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
2012 # have identity issues in that area.
1366 Net::SSLeay::CTX_set_mode ($self->{tls}, 2013# Net::SSLeay::CTX_set_mode ($ssl,
1367 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2014# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1368 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2015# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
2016 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1369 2017
1370 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2018 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1371 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2019 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1372 2020
2021 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2022 $self->{rbuf} = "";
2023
1373 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2024 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1374 2025
1375 $self->{filter_w} = sub { 2026 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1376 $_[0]{_tls_wbuf} .= ${$_[1]}; 2027 if $self->{on_starttls};
1377 &_dotls; 2028
1378 }; 2029 &_dotls; # need to trigger the initial handshake
1379 $self->{filter_r} = sub { 2030 $self->start_read; # make sure we actually do read
1380 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1381 &_dotls;
1382 };
1383} 2031}
1384 2032
1385=item $handle->stoptls 2033=item $handle->stoptls
1386 2034
1387Destroys the SSL connection, if any. Partial read or write data will be 2035Shuts down the SSL connection - this makes a proper EOF handshake by
1388lost. 2036sending a close notify to the other side, but since OpenSSL doesn't
2037support non-blocking shut downs, it is not guaranteed that you can re-use
2038the stream afterwards.
2039
2040This method may invoke callbacks (and therefore the handle might be
2041destroyed after it returns).
1389 2042
1390=cut 2043=cut
1391 2044
1392sub stoptls { 2045sub stoptls {
1393 my ($self) = @_; 2046 my ($self) = @_;
1394 2047
1395 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 2048 if ($self->{tls} && $self->{fh}) {
2049 Net::SSLeay::shutdown ($self->{tls});
1396 2050
1397 delete $self->{_rbio}; 2051 &_dotls;
1398 delete $self->{_wbio}; 2052
1399 delete $self->{_tls_wbuf}; 2053# # we don't give a shit. no, we do, but we can't. no...#d#
1400 delete $self->{filter_r}; 2054# # we, we... have to use openssl :/#d#
1401 delete $self->{filter_w}; 2055# &_freetls;#d#
2056 }
1402} 2057}
2058
2059sub _freetls {
2060 my ($self) = @_;
2061
2062 return unless $self->{tls};
2063
2064 $self->{tls_ctx}->_put_session (delete $self->{tls})
2065 if $self->{tls} > 0;
2066
2067 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2068}
2069
2070=item $handle->resettls
2071
2072This rarely-used method simply resets and TLS state on the handle, usually
2073causing data loss.
2074
2075One case where it may be useful is when you want to skip over the data in
2076the stream but you are not interested in interpreting it, so data loss is
2077no concern.
2078
2079=cut
2080
2081*resettls = \&_freetls;
1403 2082
1404sub DESTROY { 2083sub DESTROY {
1405 my $self = shift; 2084 my ($self) = @_;
1406 2085
1407 $self->stoptls; 2086 &_freetls;
1408 2087
1409 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 2088 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1410 2089
1411 if ($linger && length $self->{wbuf}) { 2090 if ($linger && length $self->{wbuf} && $self->{fh}) {
1412 my $fh = delete $self->{fh}; 2091 my $fh = delete $self->{fh};
1413 my $wbuf = delete $self->{wbuf}; 2092 my $wbuf = delete $self->{wbuf};
1414 2093
1415 my @linger; 2094 my @linger;
1416 2095
1417 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2096 push @linger, AE::io $fh, 1, sub {
1418 my $len = syswrite $fh, $wbuf, length $wbuf; 2097 my $len = syswrite $fh, $wbuf, length $wbuf;
1419 2098
1420 if ($len > 0) { 2099 if ($len > 0) {
1421 substr $wbuf, 0, $len, ""; 2100 substr $wbuf, 0, $len, "";
1422 } else { 2101 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1423 @linger = (); # end 2102 @linger = (); # end
1424 } 2103 }
2104 };
2105 push @linger, AE::timer $linger, 0, sub {
2106 @linger = ();
2107 };
2108 }
2109}
2110
2111=item $handle->destroy
2112
2113Shuts down the handle object as much as possible - this call ensures that
2114no further callbacks will be invoked and as many resources as possible
2115will be freed. Any method you will call on the handle object after
2116destroying it in this way will be silently ignored (and it will return the
2117empty list).
2118
2119Normally, you can just "forget" any references to an AnyEvent::Handle
2120object and it will simply shut down. This works in fatal error and EOF
2121callbacks, as well as code outside. It does I<NOT> work in a read or write
2122callback, so when you want to destroy the AnyEvent::Handle object from
2123within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
2124that case.
2125
2126Destroying the handle object in this way has the advantage that callbacks
2127will be removed as well, so if those are the only reference holders (as
2128is common), then one doesn't need to do anything special to break any
2129reference cycles.
2130
2131The handle might still linger in the background and write out remaining
2132data, as specified by the C<linger> option, however.
2133
2134=cut
2135
2136sub destroy {
2137 my ($self) = @_;
2138
2139 $self->DESTROY;
2140 %$self = ();
2141 bless $self, "AnyEvent::Handle::destroyed";
2142}
2143
2144sub AnyEvent::Handle::destroyed::AUTOLOAD {
2145 #nop
2146}
2147
2148=item $handle->destroyed
2149
2150Returns false as long as the handle hasn't been destroyed by a call to C<<
2151->destroy >>, true otherwise.
2152
2153Can be useful to decide whether the handle is still valid after some
2154callback possibly destroyed the handle. For example, C<< ->push_write >>,
2155C<< ->starttls >> and other methods can call user callbacks, which in turn
2156can destroy the handle, so work can be avoided by checking sometimes:
2157
2158 $hdl->starttls ("accept");
2159 return if $hdl->destroyed;
2160 $hdl->push_write (...
2161
2162Note that the call to C<push_write> will silently be ignored if the handle
2163has been destroyed, so often you can just ignore the possibility of the
2164handle being destroyed.
2165
2166=cut
2167
2168sub destroyed { 0 }
2169sub AnyEvent::Handle::destroyed::destroyed { 1 }
2170
2171=item AnyEvent::Handle::TLS_CTX
2172
2173This function creates and returns the AnyEvent::TLS object used by default
2174for TLS mode.
2175
2176The context is created by calling L<AnyEvent::TLS> without any arguments.
2177
2178=cut
2179
2180our $TLS_CTX;
2181
2182sub TLS_CTX() {
2183 $TLS_CTX ||= do {
2184 require AnyEvent::TLS;
2185
2186 new AnyEvent::TLS
2187 }
2188}
2189
2190=back
2191
2192
2193=head1 NONFREQUENTLY ASKED QUESTIONS
2194
2195=over 4
2196
2197=item I C<undef> the AnyEvent::Handle reference inside my callback and
2198still get further invocations!
2199
2200That's because AnyEvent::Handle keeps a reference to itself when handling
2201read or write callbacks.
2202
2203It is only safe to "forget" the reference inside EOF or error callbacks,
2204from within all other callbacks, you need to explicitly call the C<<
2205->destroy >> method.
2206
2207=item Why is my C<on_eof> callback never called?
2208
2209Probably because your C<on_error> callback is being called instead: When
2210you have outstanding requests in your read queue, then an EOF is
2211considered an error as you clearly expected some data.
2212
2213To avoid this, make sure you have an empty read queue whenever your handle
2214is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2215an C<on_read> handler that simply pushes the first read requests in the
2216queue.
2217
2218See also the next question, which explains this in a bit more detail.
2219
2220=item How can I serve requests in a loop?
2221
2222Most protocols consist of some setup phase (authentication for example)
2223followed by a request handling phase, where the server waits for requests
2224and handles them, in a loop.
2225
2226There are two important variants: The first (traditional, better) variant
2227handles requests until the server gets some QUIT command, causing it to
2228close the connection first (highly desirable for a busy TCP server). A
2229client dropping the connection is an error, which means this variant can
2230detect an unexpected detection close.
2231
2232To handle this case, always make sure you have a on-empty read queue, by
2233pushing the "read request start" handler on it:
2234
2235 # we assume a request starts with a single line
2236 my @start_request; @start_request = (line => sub {
2237 my ($hdl, $line) = @_;
2238
2239 ... handle request
2240
2241 # push next request read, possibly from a nested callback
2242 $hdl->push_read (@start_request);
2243 });
2244
2245 # auth done, now go into request handling loop
2246 # now push the first @start_request
2247 $hdl->push_read (@start_request);
2248
2249By always having an outstanding C<push_read>, the handle always expects
2250some data and raises the C<EPIPE> error when the connction is dropped
2251unexpectedly.
2252
2253The second variant is a protocol where the client can drop the connection
2254at any time. For TCP, this means that the server machine may run out of
2255sockets easier, and in general, it means you cannot distinguish a protocl
2256failure/client crash from a normal connection close. Nevertheless, these
2257kinds of protocols are common (and sometimes even the best solution to the
2258problem).
2259
2260Having an outstanding read request at all times is possible if you ignore
2261C<EPIPE> errors, but this doesn't help with when the client drops the
2262connection during a request, which would still be an error.
2263
2264A better solution is to push the initial request read in an C<on_read>
2265callback. This avoids an error, as when the server doesn't expect data
2266(i.e. is idly waiting for the next request, an EOF will not raise an
2267error, but simply result in an C<on_eof> callback. It is also a bit slower
2268and simpler:
2269
2270 # auth done, now go into request handling loop
2271 $hdl->on_read (sub {
2272 my ($hdl) = @_;
2273
2274 # called each time we receive data but the read queue is empty
2275 # simply start read the request
2276
2277 $hdl->push_read (line => sub {
2278 my ($hdl, $line) = @_;
2279
2280 ... handle request
2281
2282 # do nothing special when the request has been handled, just
2283 # let the request queue go empty.
1425 }); 2284 });
1426 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1427 @linger = ();
1428 }); 2285 });
2286
2287=item I get different callback invocations in TLS mode/Why can't I pause
2288reading?
2289
2290Unlike, say, TCP, TLS connections do not consist of two independent
2291communication channels, one for each direction. Or put differently, the
2292read and write directions are not independent of each other: you cannot
2293write data unless you are also prepared to read, and vice versa.
2294
2295This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2296callback invocations when you are not expecting any read data - the reason
2297is that AnyEvent::Handle always reads in TLS mode.
2298
2299During the connection, you have to make sure that you always have a
2300non-empty read-queue, or an C<on_read> watcher. At the end of the
2301connection (or when you no longer want to use it) you can call the
2302C<destroy> method.
2303
2304=item How do I read data until the other side closes the connection?
2305
2306If you just want to read your data into a perl scalar, the easiest way
2307to achieve this is by setting an C<on_read> callback that does nothing,
2308clearing the C<on_eof> callback and in the C<on_error> callback, the data
2309will be in C<$_[0]{rbuf}>:
2310
2311 $handle->on_read (sub { });
2312 $handle->on_eof (undef);
2313 $handle->on_error (sub {
2314 my $data = delete $_[0]{rbuf};
2315 });
2316
2317Note that this example removes the C<rbuf> member from the handle object,
2318which is not normally allowed by the API. It is expressly permitted in
2319this case only, as the handle object needs to be destroyed afterwards.
2320
2321The reason to use C<on_error> is that TCP connections, due to latencies
2322and packets loss, might get closed quite violently with an error, when in
2323fact all data has been received.
2324
2325It is usually better to use acknowledgements when transferring data,
2326to make sure the other side hasn't just died and you got the data
2327intact. This is also one reason why so many internet protocols have an
2328explicit QUIT command.
2329
2330=item I don't want to destroy the handle too early - how do I wait until
2331all data has been written?
2332
2333After writing your last bits of data, set the C<on_drain> callback
2334and destroy the handle in there - with the default setting of
2335C<low_water_mark> this will be called precisely when all data has been
2336written to the socket:
2337
2338 $handle->push_write (...);
2339 $handle->on_drain (sub {
2340 AE::log debug => "All data submitted to the kernel.";
2341 undef $handle;
2342 });
2343
2344If you just want to queue some data and then signal EOF to the other side,
2345consider using C<< ->push_shutdown >> instead.
2346
2347=item I want to contact a TLS/SSL server, I don't care about security.
2348
2349If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2350connect to it and then create the AnyEvent::Handle with the C<tls>
2351parameter:
2352
2353 tcp_connect $host, $port, sub {
2354 my ($fh) = @_;
2355
2356 my $handle = new AnyEvent::Handle
2357 fh => $fh,
2358 tls => "connect",
2359 on_error => sub { ... };
2360
2361 $handle->push_write (...);
1429 } 2362 };
1430}
1431 2363
1432=item AnyEvent::Handle::TLS_CTX 2364=item I want to contact a TLS/SSL server, I do care about security.
1433 2365
1434This function creates and returns the Net::SSLeay::CTX object used by 2366Then you should additionally enable certificate verification, including
1435default for TLS mode. 2367peername verification, if the protocol you use supports it (see
2368L<AnyEvent::TLS>, C<verify_peername>).
1436 2369
1437The context is created like this: 2370E.g. for HTTPS:
1438 2371
1439 Net::SSLeay::load_error_strings; 2372 tcp_connect $host, $port, sub {
1440 Net::SSLeay::SSLeay_add_ssl_algorithms; 2373 my ($fh) = @_;
1441 Net::SSLeay::randomize;
1442 2374
1443 my $CTX = Net::SSLeay::CTX_new; 2375 my $handle = new AnyEvent::Handle
2376 fh => $fh,
2377 peername => $host,
2378 tls => "connect",
2379 tls_ctx => { verify => 1, verify_peername => "https" },
2380 ...
1444 2381
1445 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL 2382Note that you must specify the hostname you connected to (or whatever
2383"peername" the protocol needs) as the C<peername> argument, otherwise no
2384peername verification will be done.
1446 2385
1447=cut 2386The above will use the system-dependent default set of trusted CA
2387certificates. If you want to check against a specific CA, add the
2388C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
1448 2389
1449our $TLS_CTX; 2390 tls_ctx => {
2391 verify => 1,
2392 verify_peername => "https",
2393 ca_file => "my-ca-cert.pem",
2394 },
1450 2395
1451sub TLS_CTX() { 2396=item I want to create a TLS/SSL server, how do I do that?
1452 $TLS_CTX || do {
1453 require Net::SSLeay;
1454 2397
1455 Net::SSLeay::load_error_strings (); 2398Well, you first need to get a server certificate and key. You have
1456 Net::SSLeay::SSLeay_add_ssl_algorithms (); 2399three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
1457 Net::SSLeay::randomize (); 2400self-signed certificate (cheap. check the search engine of your choice,
2401there are many tutorials on the net) or c) make your own CA (tinyca2 is a
2402nice program for that purpose).
1458 2403
1459 $TLS_CTX = Net::SSLeay::CTX_new (); 2404Then create a file with your private key (in PEM format, see
2405L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
2406file should then look like this:
1460 2407
1461 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ()); 2408 -----BEGIN RSA PRIVATE KEY-----
2409 ...header data
2410 ... lots of base64'y-stuff
2411 -----END RSA PRIVATE KEY-----
1462 2412
1463 $TLS_CTX 2413 -----BEGIN CERTIFICATE-----
1464 } 2414 ... lots of base64'y-stuff
1465} 2415 -----END CERTIFICATE-----
2416
2417The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
2418specify this file as C<cert_file>:
2419
2420 tcp_server undef, $port, sub {
2421 my ($fh) = @_;
2422
2423 my $handle = new AnyEvent::Handle
2424 fh => $fh,
2425 tls => "accept",
2426 tls_ctx => { cert_file => "my-server-keycert.pem" },
2427 ...
2428
2429When you have intermediate CA certificates that your clients might not
2430know about, just append them to the C<cert_file>.
1466 2431
1467=back 2432=back
1468 2433
1469=head1 SUBCLASSING AnyEvent::Handle 2434=head1 SUBCLASSING AnyEvent::Handle
1470 2435
1489 2454
1490=item * all members not documented here and not prefixed with an underscore 2455=item * all members not documented here and not prefixed with an underscore
1491are free to use in subclasses. 2456are free to use in subclasses.
1492 2457
1493Of course, new versions of AnyEvent::Handle may introduce more "public" 2458Of course, new versions of AnyEvent::Handle may introduce more "public"
1494member variables, but thats just life, at least it is documented. 2459member variables, but that's just life. At least it is documented.
1495 2460
1496=back 2461=back
1497 2462
1498=head1 AUTHOR 2463=head1 AUTHOR
1499 2464
1500Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2465Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1501 2466
1502=cut 2467=cut
1503 2468
15041; # End of AnyEvent::Handle 24691
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