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Revision 1.48 by root, Thu May 29 00:27:06 2008 UTC vs.
Revision 1.232 by root, Fri Mar 30 03:11:17 2012 UTC

1package AnyEvent::Handle;
2
3no warnings;
4use strict;
5
6use AnyEvent ();
7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util ();
9use Carp ();
10use Fcntl ();
11use Errno qw(EAGAIN EINTR);
12
13=head1 NAME 1=head1 NAME
14 2
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17=cut
18
19our $VERSION = '0.04';
20 4
21=head1 SYNOPSIS 5=head1 SYNOPSIS
22 6
23 use AnyEvent; 7 use AnyEvent;
24 use AnyEvent::Handle; 8 use AnyEvent::Handle;
25 9
26 my $cv = AnyEvent->condvar; 10 my $cv = AnyEvent->condvar;
27 11
28 my $handle = 12 my $hdl; $hdl = new AnyEvent::Handle
29 AnyEvent::Handle->new (
30 fh => \*STDIN, 13 fh => \*STDIN,
31 on_eof => sub { 14 on_error => sub {
32 $cv->broadcast; 15 my ($hdl, $fatal, $msg) = @_;
33 }, 16 AE::log error => "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
78=item on_eof => $cb->($handle) 99=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
79 100
80Set the callback to be called on EOF. 101Try to connect to the specified host and service (port), using
102C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
103default C<peername>.
81 104
82While not mandatory, it is highly recommended to set an eof callback, 105You have to specify either this parameter, or C<fh>, above.
83otherwise you might end up with a closed socket while you are still
84waiting for data.
85 106
107It is possible to push requests on the read and write queues, and modify
108properties of the stream, even while AnyEvent::Handle is connecting.
109
110When this parameter is specified, then the C<on_prepare>,
111C<on_connect_error> and C<on_connect> callbacks will be called under the
112appropriate circumstances:
113
114=over 4
115
86=item on_error => $cb->($handle) 116=item on_prepare => $cb->($handle)
87 117
118This (rarely used) callback is called before a new connection is
119attempted, but after the file handle has been created (you can access that
120file handle via C<< $handle->{fh} >>). It could be used to prepare the
121file handle with parameters required for the actual connect (as opposed to
122settings that can be changed when the connection is already established).
123
124The return value of this callback should be the connect timeout value in
125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126default timeout is to be used).
127
128=item on_connect => $cb->($handle, $host, $port, $retry->())
129
130This callback is called when a connection has been successfully established.
131
132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
140If, for some reason, the handle is not acceptable, calling C<$retry> will
141continue with the next connection target (in case of multi-homed hosts or
142SRV records there can be multiple connection endpoints). The C<$retry>
143callback can be invoked after the connect callback returns, i.e. one can
144start a handshake and then decide to retry with the next host if the
145handshake fails.
146
147In most cases, you should ignore the C<$retry> parameter.
148
149=item on_connect_error => $cb->($handle, $message)
150
151This callback is called when the connection could not be
152established. C<$!> will contain the relevant error code, and C<$message> a
153message describing it (usually the same as C<"$!">).
154
155If this callback isn't specified, then C<on_error> will be called with a
156fatal error instead.
157
158=back
159
160=item on_error => $cb->($handle, $fatal, $message)
161
88This is the fatal error callback, that is called when, well, a fatal error 162This is the error callback, which is called when, well, some error
89occurs, such as not being able to resolve the hostname, failure to connect 163occured, such as not being able to resolve the hostname, failure to
90or a read error. 164connect, or a read error.
91 165
92The object will not be in a usable state when this callback has been 166Some errors are fatal (which is indicated by C<$fatal> being true). On
93called. 167fatal errors the handle object will be destroyed (by a call to C<< ->
168destroy >>) after invoking the error callback (which means you are free to
169examine the handle object). Examples of fatal errors are an EOF condition
170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
94 173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well. It is
176recommended to always output the C<$message> argument in human-readable
177error messages (it's usually the same as C<"$!">).
178
179Non-fatal errors can be retried by returning, but it is recommended
180to simply ignore this parameter and instead abondon the handle object
181when this callback is invoked. Examples of non-fatal errors are timeouts
182C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
183
95On callback entrance, the value of C<$!> contains the operating system 184On entry to the callback, the value of C<$!> contains the operating
96error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). 185system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
97 186C<EPROTO>).
98The callback should throw an exception. If it returns, then
99AnyEvent::Handle will C<croak> for you.
100 187
101While 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
102you will not be notified of errors otherwise. The default simply calls 189you will not be notified of errors otherwise. The default just calls
103die. 190C<croak>.
104 191
105=item on_read => $cb->($handle) 192=item on_read => $cb->($handle)
106 193
107This sets the default read callback, which is called when data arrives 194This sets the default read callback, which is called when data arrives
108and no read request is in the queue. 195and no read request is in the queue (unlike read queue callbacks, this
196callback will only be called when at least one octet of data is in the
197read buffer).
109 198
110To 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 >>
111method or access the C<$handle->{rbuf}> member directly. 200method or access the C<< $handle->{rbuf} >> member directly. Note that you
201must not enlarge or modify the read buffer, you can only remove data at
202the beginning from it.
112 203
204You can also call C<< ->push_read (...) >> or any other function that
205modifies the read queue. Or do both. Or ...
206
113When an EOF condition is detected then AnyEvent::Handle will first try to 207When an EOF condition is detected, AnyEvent::Handle will first try to
114feed all the remaining data to the queued callbacks and C<on_read> before 208feed all the remaining data to the queued callbacks and C<on_read> before
115calling the C<on_eof> callback. If no progress can be made, then a fatal 209calling the C<on_eof> callback. If no progress can be made, then a fatal
116error will be raised (with C<$!> set to C<EPIPE>). 210error will be raised (with C<$!> set to C<EPIPE>).
117 211
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
118=item on_drain => $cb->($handle) 233=item on_drain => $cb->($handle)
119 234
120This 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
121(or when the callback is set and the buffer is empty already). 236empty (and immediately when the handle object is created).
122 237
123To append to the write buffer, use the C<< ->push_write >> method. 238To append to the write buffer, use the C<< ->push_write >> method.
124 239
240This callback is useful when you don't want to put all of your write data
241into the queue at once, for example, when you want to write the contents
242of some file to the socket you might not want to read the whole file into
243memory and push it into the queue, but instead only read more data from
244the file when the write queue becomes empty.
245
125=item timeout => $fractional_seconds 246=item timeout => $fractional_seconds
126 247
248=item rtimeout => $fractional_seconds
249
250=item wtimeout => $fractional_seconds
251
127If non-zero, then this enables an "inactivity" timeout: whenever this many 252If non-zero, then these enables an "inactivity" timeout: whenever this
128seconds pass without a successful read or write on the underlying file 253many seconds pass without a successful read or write on the underlying
129handle, 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
130missing, 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).
131 257
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
132Note 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
133any outstanding read or write requests: If you plan to keep the connection 266outstanding read or write requests: If you plan to keep the connection
134idle then you should disable the timout temporarily or ignore the timeout 267idle then you should disable the timeout temporarily or ignore the
135in the C<on_timeout> callback. 268timeout in the corresponding C<on_timeout> callback, in which case
269AnyEvent::Handle will simply restart the timeout.
136 270
137Zero (the default) disables this timeout. 271Zero (the default) disables the corresponding timeout.
138 272
139=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)
140 278
141Called whenever the inactivity timeout passes. If you return from this 279Called whenever the inactivity timeout passes. If you return from this
142callback, 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,
143so this condition is not fatal in any way. 281so this condition is not fatal in any way.
144 282
145=item rbuf_max => <bytes> 283=item rbuf_max => <bytes>
146 284
147If 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>)
148when 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
149avoid denial-of-service attacks. 287avoid some forms of denial-of-service attacks.
150 288
151For example, a server accepting connections from untrusted sources should 289For example, a server accepting connections from untrusted sources should
152be 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
153(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
154amount 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
155isn't finished). 293isn't finished).
156 294
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
310=item autocork => <boolean>
311
312When disabled (the default), C<push_write> will try to immediately
313write the data to the handle if possible. This avoids having to register
314a write watcher and wait for the next event loop iteration, but can
315be inefficient if you write multiple small chunks (on the wire, this
316disadvantage is usually avoided by your kernel's nagle algorithm, see
317C<no_delay>, but this option can save costly syscalls).
318
319When enabled, writes will always be queued till the next event loop
320iteration. This is efficient when you do many small writes per iteration,
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.
323
324=item no_delay => <boolean>
325
326When doing small writes on sockets, your operating system kernel might
327wait a bit for more data before actually sending it out. This is called
328the Nagle algorithm, and usually it is beneficial.
329
330In some situations you want as low a delay as possible, which can be
331accomplishd by setting this option to a true value.
332
333The default is your operating system's default behaviour (most likely
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.
367
157=item read_size => <bytes> 368=item read_size => <bytes>
158 369
159The 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
160during 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.
161 382
162=item low_water_mark => <bytes> 383=item low_water_mark => <bytes>
163 384
164Sets 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
165buffer: 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
166considered empty. 387considered empty.
167 388
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
394=item linger => <seconds>
395
396If this is non-zero (default: C<3600>), the destructor of the
397AnyEvent::Handle object will check whether there is still outstanding
398write data and will install a watcher that will write this data to the
399socket. No errors will be reported (this mostly matches how the operating
400system treats outstanding data at socket close time).
401
402This will not work for partial TLS data that could not be encoded
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>.
415
168=item tls => "accept" | "connect" | Net::SSLeay::SSL object 416=item tls => "accept" | "connect" | Net::SSLeay::SSL object
169 417
170When this parameter is given, it enables TLS (SSL) mode, that means it 418When this parameter is given, it enables TLS (SSL) mode, that means
171will start making tls handshake and will transparently encrypt/decrypt 419AnyEvent will start a TLS handshake as soon as the connection has been
172data. 420established and will transparently encrypt/decrypt data afterwards.
421
422All TLS protocol errors will be signalled as C<EPROTO>, with an
423appropriate error message.
173 424
174TLS mode requires Net::SSLeay to be installed (it will be loaded 425TLS mode requires Net::SSLeay to be installed (it will be loaded
175automatically 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.
176 429
177For 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
178connection, use C<connect> mode. 431C<accept>, and for the TLS client side of a connection, use C<connect>
432mode.
179 433
180You can also provide your own TLS connection object, but you have 434You can also provide your own TLS connection object, but you have
181to 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>
182or 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
183AnyEvent::Handle. 437AnyEvent::Handle. Also, this module will take ownership of this connection
438object.
184 439
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
185See 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.
186 450
187=item tls_ctx => $ssl_ctx 451=item tls_ctx => $anyevent_tls
188 452
189Use 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
190(unless a connection object was specified directly). If this parameter is 454(unless a connection object was specified directly). If this
191missing, 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.
192 493
193=item json => JSON or JSON::XS object 494=item json => JSON or JSON::XS object
194 495
195This 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.
196 497
197If 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
198suitable 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.
199 501
200Note 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
201use this functionality, as AnyEvent does not have a dependency itself. 503use this functionality, as AnyEvent does not have a dependency itself.
202 504
203=item filter_r => $cb
204
205=item filter_w => $cb
206
207These exist, but are undocumented at this time.
208
209=back 505=back
210 506
211=cut 507=cut
212 508
213sub new { 509sub new {
214 my $class = shift; 510 my $class = shift;
215
216 my $self = bless { @_ }, $class; 511 my $self = bless { @_ }, $class;
217 512
218 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 513 if ($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;
219 584
220 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 585 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
221 586
222 if ($self->{tls}) { 587 $self->{_activity} =
223 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
224 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 604 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
225 } 605 if $self->{tls};
226 606
227# $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; # nop
228# $self->on_error (delete $self->{on_error}) if $self->{on_error}; # nop
229# $self->on_read (delete $self->{on_read} ) if $self->{on_read}; # nop
230 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 607 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
231 608
232 $self->{_activity} = AnyEvent->now;
233 $self->_timeout;
234
235 $self->start_read; 609 $self->start_read
610 if $self->{on_read} || @{ $self->{_queue} };
236 611
237 $self 612 $self->_drain_wbuf;
238} 613}
239 614
240sub _shutdown {
241 my ($self) = @_;
242
243 delete $self->{_tw};
244 delete $self->{_rw};
245 delete $self->{_ww};
246 delete $self->{fh};
247}
248
249sub error { 615sub _error {
250 my ($self) = @_; 616 my ($self, $errno, $fatal, $message) = @_;
251 617
252 { 618 $! = $errno;
253 local $!; 619 $message ||= "$!";
254 $self->_shutdown;
255 }
256 620
257 $self->{on_error}($self)
258 if $self->{on_error}; 621 if ($self->{on_error}) {
259 622 $self->{on_error}($self, $fatal, $message);
623 $self->destroy if $fatal;
624 } elsif ($self->{fh} || $self->{connect}) {
625 $self->destroy;
260 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 626 Carp::croak "AnyEvent::Handle uncaught error: $message";
627 }
261} 628}
262 629
263=item $fh = $handle->fh 630=item $fh = $handle->fh
264 631
265This 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.
266 633
267=cut 634=cut
268 635
269sub fh { $_[0]{fh} } 636sub fh { $_[0]{fh} }
270 637
288 $_[0]{on_eof} = $_[1]; 655 $_[0]{on_eof} = $_[1];
289} 656}
290 657
291=item $handle->on_timeout ($cb) 658=item $handle->on_timeout ($cb)
292 659
293Replace the current C<on_timeout> callback, or disables the callback 660=item $handle->on_rtimeout ($cb)
294(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
295argument.
296 661
297=cut 662=item $handle->on_wtimeout ($cb)
298 663
664Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
665callback, or disables the callback (but not the timeout) if C<$cb> =
666C<undef>. See the C<timeout> constructor argument and method.
667
668=cut
669
670# see below
671
672=item $handle->autocork ($boolean)
673
674Enables or disables the current autocork behaviour (see C<autocork>
675constructor argument). Changes will only take effect on the next write.
676
677=cut
678
679sub autocork {
680 $_[0]{autocork} = $_[1];
681}
682
683=item $handle->no_delay ($boolean)
684
685Enables or disables the C<no_delay> setting (see constructor argument of
686the same name for details).
687
688=cut
689
690sub no_delay {
691 $_[0]{no_delay} = $_[1];
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
707 eval {
708 local $SIG{__DIE__};
709 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
710 if $_[0]{fh};
711 };
712}
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
299sub on_timeout { 764sub on_stoptls {
300 $_[0]{on_timeout} = $_[1]; 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];
301} 784}
302 785
303############################################################################# 786#############################################################################
304 787
305=item $handle->timeout ($seconds) 788=item $handle->timeout ($seconds)
306 789
790=item $handle->rtimeout ($seconds)
791
792=item $handle->wtimeout ($seconds)
793
307Configures (or disables) the inactivity timeout. 794Configures (or disables) the inactivity timeout.
308 795
309=cut 796The timeout will be checked instantly, so this method might destroy the
797handle before it returns.
310 798
311sub 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 {
312 my ($self, $timeout) = @_; 823 my ($self, $new_value) = @_;
313 824
825 $new_value >= 0
826 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
827
314 $self->{timeout} = $timeout; 828 $self->{$timeout} = $new_value;
315 $self->_timeout; 829 delete $self->{$tw}; &$cb;
316} 830 };
317 831
832 *{"${dir}timeout_reset"} = sub {
833 $_[0]{$activity} = AE::now;
834 };
835
836 # main workhorse:
318# reset the timeout watcher, as neccessary 837 # reset the timeout watcher, as neccessary
319# also check for time-outs 838 # also check for time-outs
320sub _timeout { 839 $cb = sub {
321 my ($self) = @_; 840 my ($self) = @_;
322 841
323 if ($self->{timeout}) { 842 if ($self->{$timeout} && $self->{fh}) {
324 my $NOW = AnyEvent->now; 843 my $NOW = AE::now;
325 844
326 # when would the timeout trigger? 845 # when would the timeout trigger?
327 my $after = $self->{_activity} + $self->{timeout} - $NOW; 846 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
328 847
329 # now or in the past already? 848 # now or in the past already?
330 if ($after <= 0) { 849 if ($after <= 0) {
331 $self->{_activity} = $NOW; 850 $self->{$activity} = $NOW;
332 851
333 if ($self->{on_timeout}) { 852 if ($self->{$on_timeout}) {
334 $self->{on_timeout}($self); 853 $self->{$on_timeout}($self);
335 } else { 854 } else {
336 $! = Errno::ETIMEDOUT; 855 $self->_error (Errno::ETIMEDOUT);
337 $self->error; 856 }
857
858 # callback could have changed timeout value, optimise
859 return unless $self->{$timeout};
860
861 # calculate new after
862 $after = $self->{$timeout};
338 } 863 }
339 864
340 # callbakx could have changed timeout value, optimise 865 Scalar::Util::weaken $self;
341 return unless $self->{timeout}; 866 return unless $self; # ->error could have destroyed $self
342 867
343 # calculate new after 868 $self->{$tw} ||= AE::timer $after, 0, sub {
344 $after = $self->{timeout}; 869 delete $self->{$tw};
870 $cb->($self);
871 };
872 } else {
873 delete $self->{$tw};
345 } 874 }
346
347 Scalar::Util::weaken $self;
348
349 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
350 delete $self->{_tw};
351 $self->_timeout;
352 });
353 } else {
354 delete $self->{_tw};
355 } 875 }
356} 876}
357 877
358############################################################################# 878#############################################################################
359 879
366 886
367The 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
368AnyEvent::Handle will automatically try to get rid of it for you. 888AnyEvent::Handle will automatically try to get rid of it for you.
369 889
370When 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
371water mark, the C<on_drain> callback will be invoked. 891water mark, the C<on_drain> callback will be invoked once.
372 892
373=over 4 893=over 4
374 894
375=item $handle->on_drain ($cb) 895=item $handle->on_drain ($cb)
376 896
377Sets 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
378C<on_drain> in the constructor). 898C<on_drain> in the constructor).
379 899
900This method may invoke callbacks (and therefore the handle might be
901destroyed after it returns).
902
380=cut 903=cut
381 904
382sub on_drain { 905sub on_drain {
383 my ($self, $cb) = @_; 906 my ($self, $cb) = @_;
384 907
385 $self->{on_drain} = $cb; 908 $self->{on_drain} = $cb;
386 909
387 $cb->($self) 910 $cb->($self)
388 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 911 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
389} 912}
390 913
391=item $handle->push_write ($data) 914=item $handle->push_write ($data)
392 915
393Queues 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
394want (only limited by the available memory), as C<AnyEvent::Handle> 917you want (only limited by the available memory and C<wbuf_max>), as
395buffers 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).
396 922
397=cut 923=cut
398 924
399sub _drain_wbuf { 925sub _drain_wbuf {
400 my ($self) = @_; 926 my ($self) = @_;
404 Scalar::Util::weaken $self; 930 Scalar::Util::weaken $self;
405 931
406 my $cb = sub { 932 my $cb = sub {
407 my $len = syswrite $self->{fh}, $self->{wbuf}; 933 my $len = syswrite $self->{fh}, $self->{wbuf};
408 934
409 if ($len >= 0) { 935 if (defined $len) {
410 substr $self->{wbuf}, 0, $len, ""; 936 substr $self->{wbuf}, 0, $len, "";
411 937
412 $self->{_activity} = AnyEvent->now; 938 $self->{_activity} = $self->{_wactivity} = AE::now;
413 939
414 $self->{on_drain}($self) 940 $self->{on_drain}($self)
415 if $self->{low_water_mark} >= length $self->{wbuf} 941 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
416 && $self->{on_drain}; 942 && $self->{on_drain};
417 943
418 delete $self->{_ww} unless length $self->{wbuf}; 944 delete $self->{_ww} unless length $self->{wbuf};
419 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 945 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
420 $self->error; 946 $self->_error ($!, 1);
421 } 947 }
422 }; 948 };
423 949
424 # try to write data immediately 950 # try to write data immediately
425 $cb->(); 951 $cb->() unless $self->{autocork};
426 952
427 # if still data left in wbuf, we need to poll 953 # if still data left in wbuf, we need to poll
428 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 954 $self->{_ww} = AE::io $self->{fh}, 1, $cb
429 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 }
430 }; 963 };
431} 964}
432 965
433our %WH; 966our %WH;
434 967
968# deprecated
435sub register_write_type($$) { 969sub register_write_type($$) {
436 $WH{$_[0]} = $_[1]; 970 $WH{$_[0]} = $_[1];
437} 971}
438 972
439sub push_write { 973sub push_write {
440 my $self = shift; 974 my $self = shift;
441 975
442 if (@_ > 1) { 976 if (@_ > 1) {
443 my $type = shift; 977 my $type = shift;
444 978
979 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
445 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 980 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
446 ->($self, @_); 981 ->($self, @_);
447 } 982 }
448 983
984 # we downgrade here to avoid hard-to-track-down bugs,
985 # and diagnose the problem earlier and better.
986
449 if ($self->{filter_w}) { 987 if ($self->{tls}) {
450 $self->{filter_w}($self, \$_[0]); 988 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
989 &_dotls ($self) if $self->{fh};
451 } else { 990 } else {
452 $self->{wbuf} .= $_[0]; 991 utf8::downgrade $self->{wbuf} .= $_[0];
453 $self->_drain_wbuf; 992 $self->_drain_wbuf if $self->{fh};
454 } 993 }
455} 994}
456 995
457=item $handle->push_write (type => @args) 996=item $handle->push_write (type => @args)
458 997
459=item $handle->unshift_write (type => @args)
460
461Instead of formatting your data yourself, you can also let this module do 998Instead of formatting your data yourself, you can also let this module
462the 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).
463 1003
464Predefined 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
465drop by and tell us): 1005drop by and tell us):
466 1006
467=over 4 1007=over 4
469=item netstring => $string 1009=item netstring => $string
470 1010
471Formats the given value as netstring 1011Formats the given value as netstring
472(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 1012(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
473 1013
474=back
475
476=cut 1014=cut
477 1015
478register_write_type netstring => sub { 1016register_write_type netstring => sub {
479 my ($self, $string) = @_; 1017 my ($self, $string) = @_;
480 1018
481 sprintf "%d:%s,", (length $string), $string 1019 (length $string) . ":$string,"
1020};
1021
1022=item packstring => $format, $data
1023
1024An octet string prefixed with an encoded length. The encoding C<$format>
1025uses the same format as a Perl C<pack> format, but must specify a single
1026integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1027optional C<!>, C<< < >> or C<< > >> modifier).
1028
1029=cut
1030
1031register_write_type packstring => sub {
1032 my ($self, $format, $string) = @_;
1033
1034 pack "$format/a*", $string
482}; 1035};
483 1036
484=item json => $array_or_hashref 1037=item json => $array_or_hashref
485 1038
486Encodes the given hash or array reference into a JSON object. Unless you 1039Encodes the given hash or array reference into a JSON object. Unless you
511Other languages could read single lines terminated by a newline and pass 1064Other languages could read single lines terminated by a newline and pass
512this line into their JSON decoder of choice. 1065this line into their JSON decoder of choice.
513 1066
514=cut 1067=cut
515 1068
1069sub json_coder() {
1070 eval { require JSON::XS; JSON::XS->new->utf8 }
1071 || do { require JSON; JSON->new->utf8 }
1072}
1073
516register_write_type json => sub { 1074register_write_type json => sub {
517 my ($self, $ref) = @_; 1075 my ($self, $ref) = @_;
518 1076
519 require JSON; 1077 my $json = $self->{json} ||= json_coder;
520 1078
521 $self->{json} ? $self->{json}->encode ($ref) 1079 $json->encode ($ref)
522 : JSON::encode_json ($ref)
523}; 1080};
524 1081
525=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1082=item storable => $reference
526 1083
527This function (not method) lets you add your own types to C<push_write>. 1084Freezes the given reference using L<Storable> and writes it to the
1085handle. Uses the C<nfreeze> format.
1086
1087=cut
1088
1089register_write_type storable => sub {
1090 my ($self, $ref) = @_;
1091
1092 require Storable unless $Storable::VERSION;
1093
1094 pack "w/a*", Storable::nfreeze ($ref)
1095};
1096
1097=back
1098
1099=item $handle->push_shutdown
1100
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
528Whenever 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
529reference with the handle object and the remaining arguments. 1136the handle object and the remaining arguments.
530 1137
531The 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
532be 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.
533 1141
534Note 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
535global, 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 }
536 1158
537=cut 1159=cut
538 1160
539############################################################################# 1161#############################################################################
540 1162
549ways, 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
550a queue. 1172a queue.
551 1173
552In 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
553new 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
554enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 1176enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
555or not. 1177leave the data there if you want to accumulate more (e.g. when only a
1178partial message has been received so far), or change the read queue with
1179e.g. C<push_read>.
556 1180
557In 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
558case, AnyEvent::Handle will call the first queued callback each time new 1182case, AnyEvent::Handle will call the first queued callback each time new
559data arrives and removes it when it has done its job (see C<push_read>, 1183data arrives (also the first time it is queued) and remove it when it has
560below). 1184done its job (see C<push_read>, below).
561 1185
562This 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
563a chunk of data, and AnyEvent::Handle will execute them in order. 1187a chunk of data, and AnyEvent::Handle will execute them in order.
564 1188
565Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 1189Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
566the specified number of bytes which give an XML datagram. 1190the specified number of bytes which give an XML datagram.
567 1191
568 # in the default state, expect some header bytes 1192 # in the default state, expect some header bytes
569 $handle->on_read (sub { 1193 $handle->on_read (sub {
570 # some data is here, now queue the length-header-read (4 octets) 1194 # some data is here, now queue the length-header-read (4 octets)
571 shift->unshift_read_chunk (4, sub { 1195 shift->unshift_read (chunk => 4, sub {
572 # header arrived, decode 1196 # header arrived, decode
573 my $len = unpack "N", $_[1]; 1197 my $len = unpack "N", $_[1];
574 1198
575 # now read the payload 1199 # now read the payload
576 shift->unshift_read_chunk ($len, sub { 1200 shift->unshift_read (chunk => $len, sub {
577 my $xml = $_[1]; 1201 my $xml = $_[1];
578 # handle xml 1202 # handle xml
579 }); 1203 });
580 }); 1204 });
581 }); 1205 });
582 1206
583Example 2: Implement a client for a protocol that replies either with 1207Example 2: Implement a client for a protocol that replies either with "OK"
584"OK" and another line or "ERROR" for one request, and 64 bytes for the 1208and another line or "ERROR" for the first request that is sent, and 64
585second request. Due tot he availability of a full queue, we can just 1209bytes for the second request. Due to the availability of a queue, we can
586pipeline sending both requests and manipulate the queue as necessary in 1210just pipeline sending both requests and manipulate the queue as necessary
587the callbacks: 1211in the callbacks.
588 1212
589 # request one 1213When the first callback is called and sees an "OK" response, it will
1214C<unshift> another line-read. This line-read will be queued I<before> the
121564-byte chunk callback.
1216
1217 # request one, returns either "OK + extra line" or "ERROR"
590 $handle->push_write ("request 1\015\012"); 1218 $handle->push_write ("request 1\015\012");
591 1219
592 # we expect "ERROR" or "OK" as response, so push a line read 1220 # we expect "ERROR" or "OK" as response, so push a line read
593 $handle->push_read_line (sub { 1221 $handle->push_read (line => sub {
594 # if we got an "OK", we have to _prepend_ another line, 1222 # if we got an "OK", we have to _prepend_ another line,
595 # so it will be read before the second request reads its 64 bytes 1223 # so it will be read before the second request reads its 64 bytes
596 # which are already in the queue when this callback is called 1224 # which are already in the queue when this callback is called
597 # we don't do this in case we got an error 1225 # we don't do this in case we got an error
598 if ($_[1] eq "OK") { 1226 if ($_[1] eq "OK") {
599 $_[0]->unshift_read_line (sub { 1227 $_[0]->unshift_read (line => sub {
600 my $response = $_[1]; 1228 my $response = $_[1];
601 ... 1229 ...
602 }); 1230 });
603 } 1231 }
604 }); 1232 });
605 1233
606 # request two 1234 # request two, simply returns 64 octets
607 $handle->push_write ("request 2\015\012"); 1235 $handle->push_write ("request 2\015\012");
608 1236
609 # simply read 64 bytes, always 1237 # simply read 64 bytes, always
610 $handle->push_read_chunk (64, sub { 1238 $handle->push_read (chunk => 64, sub {
611 my $response = $_[1]; 1239 my $response = $_[1];
612 ... 1240 ...
613 }); 1241 });
614 1242
615=over 4 1243=over 4
616 1244
617=cut 1245=cut
618 1246
619sub _drain_rbuf { 1247sub _drain_rbuf {
620 my ($self) = @_; 1248 my ($self) = @_;
1249
1250 # avoid recursion
1251 return if $self->{_skip_drain_rbuf};
1252 local $self->{_skip_drain_rbuf} = 1;
1253
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
1260 my $len = length $self->{rbuf};
1261
1262 if (my $cb = shift @{ $self->{_queue} }) {
1263 unless ($cb->($self)) {
1264 # no progress can be made
1265 # (not enough data and no data forthcoming)
1266 $self->_error (Errno::EPIPE, 1), return
1267 if $self->{_eof};
1268
1269 unshift @{ $self->{_queue} }, $cb;
1270 last;
1271 }
1272 } elsif ($self->{on_read}) {
1273 last unless $len;
1274
1275 $self->{on_read}($self);
1276
1277 if (
1278 $len == length $self->{rbuf} # if no data has been consumed
1279 && !@{ $self->{_queue} } # and the queue is still empty
1280 && $self->{on_read} # but we still have on_read
1281 ) {
1282 # no further data will arrive
1283 # so no progress can be made
1284 $self->_error (Errno::EPIPE, 1), return
1285 if $self->{_eof};
1286
1287 last; # more data might arrive
1288 }
1289 } else {
1290 # read side becomes idle
1291 delete $self->{_rw} unless $self->{tls};
1292 last;
1293 }
1294 }
1295
1296 if ($self->{_eof}) {
1297 $self->{on_eof}
1298 ? $self->{on_eof}($self)
1299 : $self->_error (0, 1, "Unexpected end-of-file");
1300
1301 return;
1302 }
621 1303
622 if ( 1304 if (
623 defined $self->{rbuf_max} 1305 defined $self->{rbuf_max}
624 && $self->{rbuf_max} < length $self->{rbuf} 1306 && $self->{rbuf_max} < length $self->{rbuf}
625 ) { 1307 ) {
626 $! = &Errno::ENOSPC; 1308 $self->_error (Errno::ENOSPC, 1), return;
627 $self->error;
628 } 1309 }
629 1310
630 return if $self->{in_drain}; 1311 # may need to restart read watcher
631 local $self->{in_drain} = 1; 1312 unless ($self->{_rw}) {
632 1313 $self->start_read
633 while (my $len = length $self->{rbuf}) { 1314 if $self->{on_read} || @{ $self->{_queue} };
634 no strict 'refs';
635 if (my $cb = shift @{ $self->{_queue} }) {
636 unless ($cb->($self)) {
637 if ($self->{_eof}) {
638 # no progress can be made (not enough data and no data forthcoming)
639 $! = &Errno::EPIPE;
640 $self->error;
641 }
642
643 unshift @{ $self->{_queue} }, $cb;
644 return;
645 }
646 } elsif ($self->{on_read}) {
647 $self->{on_read}($self);
648
649 if (
650 $self->{_eof} # if no further data will arrive
651 && $len == length $self->{rbuf} # and no data has been consumed
652 && !@{ $self->{_queue} } # and the queue is still empty
653 && $self->{on_read} # and we still want to read data
654 ) {
655 # then no progress can be made
656 $! = &Errno::EPIPE;
657 $self->error;
658 }
659 } else {
660 # read side becomes idle
661 delete $self->{_rw};
662 return;
663 }
664 } 1315 }
665
666 $self->{on_eof}($self)
667 if $self->{_eof} && $self->{on_eof};
668} 1316}
669 1317
670=item $handle->on_read ($cb) 1318=item $handle->on_read ($cb)
671 1319
672This 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
673the 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
674constructor. 1322constructor.
675 1323
1324This method may invoke callbacks (and therefore the handle might be
1325destroyed after it returns).
1326
676=cut 1327=cut
677 1328
678sub on_read { 1329sub on_read {
679 my ($self, $cb) = @_; 1330 my ($self, $cb) = @_;
680 1331
681 $self->{on_read} = $cb; 1332 $self->{on_read} = $cb;
1333 $self->_drain_rbuf if $cb;
682} 1334}
683 1335
684=item $handle->rbuf 1336=item $handle->rbuf
685 1337
686Returns 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).
687 1341
688You 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)
689you 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.
690 1345
691NOTE: 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>
692C<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
693automatically 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.
694 1350
695=cut 1351=cut
696 1352
697sub rbuf : lvalue { 1353sub rbuf : lvalue {
698 $_[0]{rbuf} 1354 $_[0]{rbuf}
715 1371
716If 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
717interested 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
718true, it will be removed from the queue. 1374true, it will be removed from the queue.
719 1375
1376These methods may invoke callbacks (and therefore the handle might be
1377destroyed after it returns).
1378
720=cut 1379=cut
721 1380
722our %RH; 1381our %RH;
723 1382
724sub register_read_type($$) { 1383sub register_read_type($$) {
730 my $cb = pop; 1389 my $cb = pop;
731 1390
732 if (@_) { 1391 if (@_) {
733 my $type = shift; 1392 my $type = shift;
734 1393
1394 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
735 $cb = ($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")
736 ->($self, $cb, @_); 1396 ->($self, $cb, @_);
737 } 1397 }
738 1398
739 push @{ $self->{_queue} }, $cb; 1399 push @{ $self->{_queue} }, $cb;
740 $self->_drain_rbuf; 1400 $self->_drain_rbuf;
745 my $cb = pop; 1405 my $cb = pop;
746 1406
747 if (@_) { 1407 if (@_) {
748 my $type = shift; 1408 my $type = shift;
749 1409
1410 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
750 $cb = ($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")
751 ->($self, $cb, @_); 1412 ->($self, $cb, @_);
752 } 1413 }
753
754 1414
755 unshift @{ $self->{_queue} }, $cb; 1415 unshift @{ $self->{_queue} }, $cb;
756 $self->_drain_rbuf; 1416 $self->_drain_rbuf;
757} 1417}
758 1418
760 1420
761=item $handle->unshift_read (type => @args, $cb) 1421=item $handle->unshift_read (type => @args, $cb)
762 1422
763Instead 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
764between a number of predefined parsing formats, for chunks of data, lines 1424between a number of predefined parsing formats, for chunks of data, lines
765etc. 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).
766 1428
767Predefined 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
768drop by and tell us): 1430drop by and tell us):
769 1431
770=over 4 1432=over 4
776data. 1438data.
777 1439
778Example: read 2 bytes. 1440Example: read 2 bytes.
779 1441
780 $handle->push_read (chunk => 2, sub { 1442 $handle->push_read (chunk => 2, sub {
781 warn "yay ", unpack "H*", $_[1]; 1443 say "yay " . unpack "H*", $_[1];
782 }); 1444 });
783 1445
784=cut 1446=cut
785 1447
786register_read_type chunk => sub { 1448register_read_type chunk => sub {
791 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 1453 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
792 1 1454 1
793 } 1455 }
794}; 1456};
795 1457
796# compatibility with older API
797sub push_read_chunk {
798 $_[0]->push_read (chunk => $_[1], $_[2]);
799}
800
801sub unshift_read_chunk {
802 $_[0]->unshift_read (chunk => $_[1], $_[2]);
803}
804
805=item line => [$eol, ]$cb->($handle, $line, $eol) 1458=item line => [$eol, ]$cb->($handle, $line, $eol)
806 1459
807The callback will be called only once a full line (including the end of 1460The callback will be called only once a full line (including the end of
808line marker, C<$eol>) has been read. This line (excluding the end of line 1461line marker, C<$eol>) has been read. This line (excluding the end of line
809marker) will be passed to the callback as second argument (C<$line>), and 1462marker) will be passed to the callback as second argument (C<$line>), and
824=cut 1477=cut
825 1478
826register_read_type line => sub { 1479register_read_type line => sub {
827 my ($self, $cb, $eol) = @_; 1480 my ($self, $cb, $eol) = @_;
828 1481
829 $eol = qr|(\015?\012)| if @_ < 3; 1482 if (@_ < 3) {
830 $eol = quotemeta $eol unless ref $eol; 1483 # this is more than twice as fast as the generic code below
831 $eol = qr|^(.*?)($eol)|s;
832
833 sub { 1484 sub {
834 $_[0]{rbuf} =~ s/$eol// or return; 1485 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
835 1486
836 $cb->($_[0], $1, $2); 1487 $cb->($_[0], "$1", "$2");
837 1
838 }
839};
840
841# compatibility with older API
842sub push_read_line {
843 my $self = shift;
844 $self->push_read (line => @_);
845}
846
847sub unshift_read_line {
848 my $self = shift;
849 $self->unshift_read (line => @_);
850}
851
852=item netstring => $cb->($handle, $string)
853
854A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
855
856Throws an error with C<$!> set to EBADMSG on format violations.
857
858=cut
859
860register_read_type netstring => sub {
861 my ($self, $cb) = @_;
862
863 sub {
864 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
865 if ($_[0]{rbuf} =~ /[^0-9]/) {
866 $! = &Errno::EBADMSG;
867 $self->error;
868 } 1488 1
869 return;
870 } 1489 }
1490 } else {
1491 $eol = quotemeta $eol unless ref $eol;
1492 $eol = qr|^(.*?)($eol)|s;
871 1493
872 my $len = $1; 1494 sub {
1495 $_[0]{rbuf} =~ s/$eol// or return;
873 1496
874 $self->unshift_read (chunk => $len, sub { 1497 $cb->($_[0], "$1", "$2");
875 my $string = $_[1];
876 $_[0]->unshift_read (chunk => 1, sub {
877 if ($_[1] eq ",") {
878 $cb->($_[0], $string);
879 } else {
880 $! = &Errno::EBADMSG;
881 $self->error;
882 }
883 }); 1498 1
884 }); 1499 }
885
886 1
887 } 1500 }
888}; 1501};
889 1502
890=item regex => $accept[, $reject[, $skip], $cb->($handle, $data) 1503=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
891 1504
911the receive buffer when neither C<$accept> nor C<$reject> match, 1524the receive buffer when neither C<$accept> nor C<$reject> match,
912and everything preceding and including the match will be accepted 1525and everything preceding and including the match will be accepted
913unconditionally. This is useful to skip large amounts of data that you 1526unconditionally. This is useful to skip large amounts of data that you
914know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1527know cannot be matched, so that the C<$accept> or C<$reject> regex do not
915have to start matching from the beginning. This is purely an optimisation 1528have to start matching from the beginning. This is purely an optimisation
916and 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.
917 1530
918Example: 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
919expect 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
920a 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
921it 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
922required for the accept regex. 1535required for the accept regex.
923 1536
924 $handle->push_read (regex => 1537 $handle->push_read (regex =>
937 1550
938 sub { 1551 sub {
939 # accept 1552 # accept
940 if ($$rbuf =~ $accept) { 1553 if ($$rbuf =~ $accept) {
941 $data .= substr $$rbuf, 0, $+[0], ""; 1554 $data .= substr $$rbuf, 0, $+[0], "";
942 $cb->($self, $data); 1555 $cb->($_[0], $data);
943 return 1; 1556 return 1;
944 } 1557 }
945 1558
946 # reject 1559 # reject
947 if ($reject && $$rbuf =~ $reject) { 1560 if ($reject && $$rbuf =~ $reject) {
948 $! = &Errno::EBADMSG; 1561 $_[0]->_error (Errno::EBADMSG);
949 $self->error;
950 } 1562 }
951 1563
952 # skip 1564 # skip
953 if ($skip && $$rbuf =~ $skip) { 1565 if ($skip && $$rbuf =~ $skip) {
954 $data .= substr $$rbuf, 0, $+[0], ""; 1566 $data .= substr $$rbuf, 0, $+[0], "";
956 1568
957 () 1569 ()
958 } 1570 }
959}; 1571};
960 1572
1573=item netstring => $cb->($handle, $string)
1574
1575A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1576
1577Throws an error with C<$!> set to EBADMSG on format violations.
1578
1579=cut
1580
1581register_read_type netstring => sub {
1582 my ($self, $cb) = @_;
1583
1584 sub {
1585 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1586 if ($_[0]{rbuf} =~ /[^0-9]/) {
1587 $_[0]->_error (Errno::EBADMSG);
1588 }
1589 return;
1590 }
1591
1592 my $len = $1;
1593
1594 $_[0]->unshift_read (chunk => $len, sub {
1595 my $string = $_[1];
1596 $_[0]->unshift_read (chunk => 1, sub {
1597 if ($_[1] eq ",") {
1598 $cb->($_[0], $string);
1599 } else {
1600 $_[0]->_error (Errno::EBADMSG);
1601 }
1602 });
1603 });
1604
1605 1
1606 }
1607};
1608
1609=item packstring => $format, $cb->($handle, $string)
1610
1611An octet string prefixed with an encoded length. The encoding C<$format>
1612uses the same format as a Perl C<pack> format, but must specify a single
1613integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1614optional C<!>, C<< < >> or C<< > >> modifier).
1615
1616For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1617EPP uses a prefix of C<N> (4 octtes).
1618
1619Example: read a block of data prefixed by its length in BER-encoded
1620format (very efficient).
1621
1622 $handle->push_read (packstring => "w", sub {
1623 my ($handle, $data) = @_;
1624 });
1625
1626=cut
1627
1628register_read_type packstring => sub {
1629 my ($self, $cb, $format) = @_;
1630
1631 sub {
1632 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1633 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1634 or return;
1635
1636 $format = length pack $format, $len;
1637
1638 # bypass unshift if we already have the remaining chunk
1639 if ($format + $len <= length $_[0]{rbuf}) {
1640 my $data = substr $_[0]{rbuf}, $format, $len;
1641 substr $_[0]{rbuf}, 0, $format + $len, "";
1642 $cb->($_[0], $data);
1643 } else {
1644 # remove prefix
1645 substr $_[0]{rbuf}, 0, $format, "";
1646
1647 # read remaining chunk
1648 $_[0]->unshift_read (chunk => $len, $cb);
1649 }
1650
1651 1
1652 }
1653};
1654
961=item json => $cb->($handle, $hash_or_arrayref) 1655=item json => $cb->($handle, $hash_or_arrayref)
962 1656
963Reads a JSON object or array, decodes it and passes it to the callback. 1657Reads a JSON object or array, decodes it and passes it to the
1658callback. When a parse error occurs, an C<EBADMSG> error will be raised.
964 1659
965If a C<json> object was passed to the constructor, then that will be used 1660If a C<json> object was passed to the constructor, then that will be used
966for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1661for the final decode, otherwise it will create a JSON coder expecting UTF-8.
967 1662
968This read type uses the incremental parser available with JSON version 1663This read type uses the incremental parser available with JSON version
975the C<json> write type description, above, for an actual example. 1670the C<json> write type description, above, for an actual example.
976 1671
977=cut 1672=cut
978 1673
979register_read_type json => sub { 1674register_read_type json => sub {
980 my ($self, $cb, $accept, $reject, $skip) = @_; 1675 my ($self, $cb) = @_;
981 1676
982 require JSON; 1677 my $json = $self->{json} ||= json_coder;
983 1678
984 my $data; 1679 my $data;
985 my $rbuf = \$self->{rbuf}; 1680 my $rbuf = \$self->{rbuf};
986 1681
987 my $json = $self->{json} ||= JSON->new->utf8;
988
989 sub { 1682 sub {
990 my $ref = $json->incr_parse ($self->{rbuf}); 1683 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
991 1684
992 if ($ref) { 1685 if ($ref) {
993 $self->{rbuf} = $json->incr_text; 1686 $_[0]{rbuf} = $json->incr_text;
994 $json->incr_text = ""; 1687 $json->incr_text = "";
995 $cb->($self, $ref); 1688 $cb->($_[0], $ref);
996 1689
997 1 1690 1
1691 } elsif ($@) {
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 ()
998 } else { 1701 } else {
999 $self->{rbuf} = ""; 1702 $_[0]{rbuf} = "";
1703
1000 () 1704 ()
1001 } 1705 }
1002 } 1706 }
1003}; 1707};
1004 1708
1709=item storable => $cb->($handle, $ref)
1710
1711Deserialises a L<Storable> frozen representation as written by the
1712C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1713data).
1714
1715Raises C<EBADMSG> error if the data could not be decoded.
1716
1717=cut
1718
1719register_read_type storable => sub {
1720 my ($self, $cb) = @_;
1721
1722 require Storable unless $Storable::VERSION;
1723
1724 sub {
1725 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1726 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1727 or return;
1728
1729 my $format = length pack "w", $len;
1730
1731 # bypass unshift if we already have the remaining chunk
1732 if ($format + $len <= length $_[0]{rbuf}) {
1733 my $data = substr $_[0]{rbuf}, $format, $len;
1734 substr $_[0]{rbuf}, 0, $format + $len, "";
1735
1736 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1737 or return $_[0]->_error (Errno::EBADMSG);
1738 } else {
1739 # remove prefix
1740 substr $_[0]{rbuf}, 0, $format, "";
1741
1742 # read remaining chunk
1743 $_[0]->unshift_read (chunk => $len, sub {
1744 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1745 or $_[0]->_error (Errno::EBADMSG);
1746 });
1747 }
1748
1749 1
1750 }
1751};
1752
1005=back 1753=back
1006 1754
1007=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1755=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1008 1756
1009This function (not method) lets you add your own types to C<push_read>. 1757Instead of one of the predefined types, you can also specify the name
1758of a package. AnyEvent will try to load the package and then expects to
1759find a function named C<anyevent_read_type> inside. If it isn't found, it
1760progressively tries to load the parent package until it either finds the
1761function (good) or runs out of packages (bad).
1010 1762
1011Whenever the given C<type> is used, C<push_read> will invoke the code 1763Whenever this type is used, C<push_read> will invoke the function with the
1012reference with the handle object, the callback and the remaining 1764handle object, the original callback and the remaining arguments.
1013arguments.
1014 1765
1015The code reference is supposed to return a callback (usually a closure) 1766The function is supposed to return a callback (usually a closure) that
1016that works as a plain read callback (see C<< ->push_read ($cb) >>). 1767works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1768mentally treat the function as a "configurable read type to read callback"
1769converter.
1017 1770
1018It should invoke the passed callback when it is done reading (remember to 1771It should invoke the original callback when it is done reading (remember
1019pass C<$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).
1020 1774
1021Note that this is a function, and all types registered this way will be
1022global, so try to use unique names.
1023
1024For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1775For examples, see the source of this module (F<perldoc -m
1025search for C<register_read_type>)). 1776AnyEvent::Handle>, search for C<register_read_type>)).
1026 1777
1027=item $handle->stop_read 1778=item $handle->stop_read
1028 1779
1029=item $handle->start_read 1780=item $handle->start_read
1030 1781
1031In rare cases you actually do not want to read anything from the 1782In rare cases you actually do not want to read anything from the
1032socket. In this case you can call C<stop_read>. Neither C<on_read> no 1783socket. In this case you can call C<stop_read>. Neither C<on_read> nor
1033any queued callbacks will be executed then. To start reading again, call 1784any queued callbacks will be executed then. To start reading again, call
1034C<start_read>. 1785C<start_read>.
1035 1786
1787Note that AnyEvent::Handle will automatically C<start_read> for you when
1788you change the C<on_read> callback or push/unshift a read callback, and it
1789will automatically C<stop_read> for you when neither C<on_read> is set nor
1790there are any read requests in the queue.
1791
1792In older versions of this module (<= 5.3), these methods had no effect,
1793as TLS does not support half-duplex connections. In current versions they
1794work as expected, as this behaviour is required to avoid certain resource
1795attacks, where the program would be forced to read (and buffer) arbitrary
1796amounts of data before being able to send some data. The drawback is that
1797some readings of the the SSL/TLS specifications basically require this
1798attack to be working, as SSL/TLS implementations might stall sending data
1799during a rehandshake.
1800
1801As a guideline, during the initial handshake, you should not stop reading,
1802and as a client, it might cause problems, depending on your application.
1803
1036=cut 1804=cut
1037 1805
1038sub stop_read { 1806sub stop_read {
1039 my ($self) = @_; 1807 my ($self) = @_;
1040 1808
1042} 1810}
1043 1811
1044sub start_read { 1812sub start_read {
1045 my ($self) = @_; 1813 my ($self) = @_;
1046 1814
1047 unless ($self->{_rw} || $self->{_eof}) { 1815 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1048 Scalar::Util::weaken $self; 1816 Scalar::Util::weaken $self;
1049 1817
1050 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1818 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1051 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1819 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1052 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1820 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1053 1821
1054 if ($len > 0) { 1822 if ($len > 0) {
1055 $self->{_activity} = AnyEvent->now; 1823 $self->{_activity} = $self->{_ractivity} = AE::now;
1056 1824
1057 $self->{filter_r} 1825 if ($self->{tls}) {
1058 ? $self->{filter_r}($self, $rbuf) 1826 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1827
1828 &_dotls ($self);
1829 } else {
1059 : $self->_drain_rbuf; 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 }
1060 1838
1061 } elsif (defined $len) { 1839 } elsif (defined $len) {
1062 delete $self->{_rw}; 1840 delete $self->{_rw};
1063 $self->{_eof} = 1; 1841 $self->{_eof} = 1;
1064 $self->_drain_rbuf; 1842 $self->_drain_rbuf;
1065 1843
1066 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1844 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1067 return $self->error; 1845 return $self->_error ($!, 1);
1068 } 1846 }
1069 }); 1847 };
1070 } 1848 }
1071} 1849}
1072 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, $err);
1871 }
1872}
1873
1874# poll the write BIO and send the data if applicable
1875# also decode read data if possible
1876# this is basiclaly our TLS state machine
1877# more efficient implementations are possible with openssl,
1878# but not with the buggy and incomplete Net::SSLeay.
1073sub _dotls { 1879sub _dotls {
1074 my ($self) = @_; 1880 my ($self) = @_;
1075 1881
1882 my $tmp;
1883
1076 if (length $self->{_tls_wbuf}) { 1884 if (length $self->{_tls_wbuf}) {
1077 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1885 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1078 substr $self->{_tls_wbuf}, 0, $len, ""; 1886 substr $self->{_tls_wbuf}, 0, $tmp, "";
1079 } 1887 }
1080 }
1081 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
1082 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1921 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1083 $self->{wbuf} .= $buf; 1922 $self->{wbuf} .= $tmp;
1084 $self->_drain_wbuf; 1923 $self->_drain_wbuf;
1924 $self->{tls} or return; # tls session might have gone away in callback
1085 } 1925 }
1086 1926
1087 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) { 1927 $self->{_on_starttls}
1088 $self->{rbuf} .= $buf; 1928 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1089 $self->_drain_rbuf; 1929 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1090 }
1091
1092 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1093
1094 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1095 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1096 $self->error;
1097 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1098 $! = &Errno::EIO;
1099 $self->error;
1100 }
1101
1102 # all others are fine for our purposes
1103 }
1104} 1930}
1105 1931
1106=item $handle->starttls ($tls[, $tls_ctx]) 1932=item $handle->starttls ($tls[, $tls_ctx])
1107 1933
1108Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1934Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1109object 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
1110C<starttls>. 1936C<starttls>.
1111 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
1112The 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
1113C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1943C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1114 1944
1115The 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
1116used 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.
1117 1949
1118The 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
1119call and can be used or changed to your liking. Note that the handshake 1951context in C<< $handle->{tls_ctx} >> after this call and can be used or
1120might have already started when this function returns. 1952changed to your liking. Note that the handshake might have already started
1953when this function returns.
1121 1954
1122=cut 1955Due to bugs in OpenSSL, it might or might not be possible to do multiple
1956handshakes on the same stream. It is best to not attempt to use the
1957stream after stopping TLS.
1123 1958
1124# TODO: maybe document... 1959This method may invoke callbacks (and therefore the handle might be
1960destroyed after it returns).
1961
1962=cut
1963
1964our %TLS_CACHE; #TODO not yet documented, should we?
1965
1125sub starttls { 1966sub starttls {
1126 my ($self, $ssl, $ctx) = @_; 1967 my ($self, $tls, $ctx) = @_;
1127 1968
1128 $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 $self->{tls};
1129 1971
1130 if ($ssl eq "accept") { 1972 $self->{tls} = $tls;
1131 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1973 $self->{tls_ctx} = $ctx if @_ > 2;
1132 Net::SSLeay::set_accept_state ($ssl); 1974
1133 } elsif ($ssl eq "connect") { 1975 return unless $self->{fh};
1134 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1976
1135 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 }
1136 } 1997
1137 1998 $self->{tls_ctx} = $ctx || TLS_CTX ();
1138 $self->{tls} = $ssl; 1999 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1139 2000
1140 # basically, this is deep magic (because SSL_read should have the same issues) 2001 # basically, this is deep magic (because SSL_read should have the same issues)
1141 # but the openssl maintainers basically said: "trust us, it just works". 2002 # but the openssl maintainers basically said: "trust us, it just works".
1142 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2003 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1143 # and mismaintained ssleay-module doesn't even offer them). 2004 # and mismaintained ssleay-module doesn't even offer them).
1144 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 2005 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
2006 #
2007 # in short: this is a mess.
2008 #
2009 # note that we do not try to keep the length constant between writes as we are required to do.
2010 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
2011 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
2012 # have identity issues in that area.
1145 Net::SSLeay::CTX_set_mode ($self->{tls}, 2013# Net::SSLeay::CTX_set_mode ($ssl,
1146 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2014# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1147 | (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);
1148 2017
1149 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2018 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1150 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2019 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1151 2020
2021 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2022 $self->{rbuf} = "";
2023
1152 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2024 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1153 2025
1154 $self->{filter_w} = sub { 2026 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1155 $_[0]{_tls_wbuf} .= ${$_[1]}; 2027 if $self->{on_starttls};
1156 &_dotls; 2028
1157 }; 2029 &_dotls; # need to trigger the initial handshake
1158 $self->{filter_r} = sub { 2030 $self->start_read; # make sure we actually do read
1159 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1160 &_dotls;
1161 };
1162} 2031}
1163 2032
1164=item $handle->stoptls 2033=item $handle->stoptls
1165 2034
1166Destroys the SSL connection, if any. Partial read or write data will be 2035Shuts down the SSL connection - this makes a proper EOF handshake by
1167lost. 2036sending a close notify to the other side, but since OpenSSL doesn't
2037support non-blocking shut downs, it is not guaranteed that you can re-use
2038the stream afterwards.
2039
2040This method may invoke callbacks (and therefore the handle might be
2041destroyed after it returns).
1168 2042
1169=cut 2043=cut
1170 2044
1171sub stoptls { 2045sub stoptls {
1172 my ($self) = @_; 2046 my ($self) = @_;
1173 2047
1174 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 2048 if ($self->{tls} && $self->{fh}) {
2049 Net::SSLeay::shutdown ($self->{tls});
1175 2050
1176 delete $self->{_rbio}; 2051 &_dotls;
1177 delete $self->{_wbio}; 2052
1178 delete $self->{_tls_wbuf}; 2053# # we don't give a shit. no, we do, but we can't. no...#d#
1179 delete $self->{filter_r}; 2054# # we, we... have to use openssl :/#d#
1180 delete $self->{filter_w}; 2055# &_freetls;#d#
2056 }
1181} 2057}
2058
2059sub _freetls {
2060 my ($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;
1182 2082
1183sub DESTROY { 2083sub DESTROY {
1184 my $self = shift; 2084 my ($self) = @_;
1185 2085
1186 $self->stoptls; 2086 &_freetls;
2087
2088 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
2089
2090 if ($linger && length $self->{wbuf} && $self->{fh}) {
2091 my $fh = delete $self->{fh};
2092 my $wbuf = delete $self->{wbuf};
2093
2094 my @linger;
2095
2096 push @linger, AE::io $fh, 1, sub {
2097 my $len = syswrite $fh, $wbuf, length $wbuf;
2098
2099 if ($len > 0) {
2100 substr $wbuf, 0, $len, "";
2101 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
2102 @linger = (); # end
2103 }
2104 };
2105 push @linger, AE::timer $linger, 0, sub {
2106 @linger = ();
2107 };
2108 }
1187} 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 }
1188 2170
1189=item AnyEvent::Handle::TLS_CTX 2171=item AnyEvent::Handle::TLS_CTX
1190 2172
1191This function creates and returns the Net::SSLeay::CTX object used by 2173This function creates and returns the AnyEvent::TLS object used by default
1192default for TLS mode. 2174for TLS mode.
1193 2175
1194The context is created like this: 2176The context is created by calling L<AnyEvent::TLS> without any arguments.
1195
1196 Net::SSLeay::load_error_strings;
1197 Net::SSLeay::SSLeay_add_ssl_algorithms;
1198 Net::SSLeay::randomize;
1199
1200 my $CTX = Net::SSLeay::CTX_new;
1201
1202 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1203 2177
1204=cut 2178=cut
1205 2179
1206our $TLS_CTX; 2180our $TLS_CTX;
1207 2181
1208sub TLS_CTX() { 2182sub TLS_CTX() {
1209 $TLS_CTX || do { 2183 $TLS_CTX ||= do {
1210 require Net::SSLeay; 2184 require AnyEvent::TLS;
1211 2185
1212 Net::SSLeay::load_error_strings (); 2186 new AnyEvent::TLS
1213 Net::SSLeay::SSLeay_add_ssl_algorithms (); 2187 }
1214 Net::SSLeay::randomize (); 2188}
1215 2189
1216 $TLS_CTX = Net::SSLeay::CTX_new (); 2190=back
1217 2191
1218 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1219 2192
1220 $TLS_CTX 2193=head1 NONFREQUENTLY ASKED QUESTIONS
2194
2195=over 4
2196
2197=item I C<undef> the AnyEvent::Handle reference inside my callback and
2198still get further invocations!
2199
2200That's because AnyEvent::Handle keeps a reference to itself when handling
2201read or write callbacks.
2202
2203It is only safe to "forget" the reference inside EOF or error callbacks,
2204from within all other callbacks, you need to explicitly call the C<<
2205->destroy >> method.
2206
2207=item Why is my C<on_eof> callback never called?
2208
2209Probably because your C<on_error> callback is being called instead: When
2210you have outstanding requests in your read queue, then an EOF is
2211considered an error as you clearly expected some data.
2212
2213To avoid this, make sure you have an empty read queue whenever your handle
2214is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2215an C<on_read> handler that simply pushes the first read requests in the
2216queue.
2217
2218See also the next question, which explains this in a bit more detail.
2219
2220=item How can I serve requests in a loop?
2221
2222Most protocols consist of some setup phase (authentication for example)
2223followed by a request handling phase, where the server waits for requests
2224and handles them, in a loop.
2225
2226There are two important variants: The first (traditional, better) variant
2227handles requests until the server gets some QUIT command, causing it to
2228close the connection first (highly desirable for a busy TCP server). A
2229client dropping the connection is an error, which means this variant can
2230detect an unexpected detection close.
2231
2232To handle this case, always make sure you have a on-empty read queue, by
2233pushing the "read request start" handler on it:
2234
2235 # we assume a request starts with a single line
2236 my @start_request; @start_request = (line => sub {
2237 my ($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, $line) = @_;
2279
2280 ... handle request
2281
2282 # do nothing special when the request has been handled, just
2283 # let the request queue go empty.
2284 });
2285 });
2286
2287=item I get different callback invocations in TLS mode/Why can't I pause
2288reading?
2289
2290Unlike, say, TCP, TLS connections do not consist of two independent
2291communication channels, one for each direction. Or put differently, the
2292read and write directions are not independent of each other: you cannot
2293write data unless you are also prepared to read, and vice versa.
2294
2295This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2296callback invocations when you are not expecting any read data - the reason
2297is that AnyEvent::Handle always reads in TLS mode.
2298
2299During the connection, you have to make sure that you always have a
2300non-empty read-queue, or an C<on_read> watcher. At the end of the
2301connection (or when you no longer want to use it) you can call the
2302C<destroy> method.
2303
2304=item How do I read data until the other side closes the connection?
2305
2306If you just want to read your data into a perl scalar, the easiest way
2307to achieve this is by setting an C<on_read> callback that does nothing,
2308clearing the C<on_eof> callback and in the C<on_error> callback, the data
2309will be in C<$_[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 (...);
1221 } 2362 };
1222} 2363
2364=item I want to contact a TLS/SSL server, I do care about security.
2365
2366Then you should additionally enable certificate verification, including
2367peername verification, if the protocol you use supports it (see
2368L<AnyEvent::TLS>, C<verify_peername>).
2369
2370E.g. for HTTPS:
2371
2372 tcp_connect $host, $port, sub {
2373 my ($fh) = @_;
2374
2375 my $handle = new AnyEvent::Handle
2376 fh => $fh,
2377 peername => $host,
2378 tls => "connect",
2379 tls_ctx => { verify => 1, verify_peername => "https" },
2380 ...
2381
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.
2385
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>:
2389
2390 tls_ctx => {
2391 verify => 1,
2392 verify_peername => "https",
2393 ca_file => "my-ca-cert.pem",
2394 },
2395
2396=item I want to create a TLS/SSL server, how do I do that?
2397
2398Well, you first need to get a server certificate and key. You have
2399three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
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).
2403
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:
2407
2408 -----BEGIN RSA PRIVATE KEY-----
2409 ...header data
2410 ... lots of base64'y-stuff
2411 -----END RSA PRIVATE KEY-----
2412
2413 -----BEGIN CERTIFICATE-----
2414 ... lots of base64'y-stuff
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>.
1223 2431
1224=back 2432=back
1225 2433
1226=head1 SUBCLASSING AnyEvent::Handle 2434=head1 SUBCLASSING AnyEvent::Handle
1227 2435
1233=over 4 2441=over 4
1234 2442
1235=item * all constructor arguments become object members. 2443=item * all constructor arguments become object members.
1236 2444
1237At least initially, when you pass a C<tls>-argument to the constructor it 2445At least initially, when you pass a C<tls>-argument to the constructor it
1238will end up in C<< $handle->{tls} >>. Those members might be changes or 2446will end up in C<< $handle->{tls} >>. Those members might be changed or
1239mutated later on (for example C<tls> will hold the TLS connection object). 2447mutated later on (for example C<tls> will hold the TLS connection object).
1240 2448
1241=item * other object member names are prefixed with an C<_>. 2449=item * other object member names are prefixed with an C<_>.
1242 2450
1243All object members not explicitly documented (internal use) are prefixed 2451All object members not explicitly documented (internal use) are prefixed
1246 2454
1247=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
1248are free to use in subclasses. 2456are free to use in subclasses.
1249 2457
1250Of course, new versions of AnyEvent::Handle may introduce more "public" 2458Of course, new versions of AnyEvent::Handle may introduce more "public"
1251member variables, but thats just life, at least it is documented. 2459member variables, but that's just life. At least it is documented.
1252 2460
1253=back 2461=back
1254 2462
1255=head1 AUTHOR 2463=head1 AUTHOR
1256 2464
1257Robin 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>.
1258 2466
1259=cut 2467=cut
1260 2468
12611; # End of AnyEvent::Handle 24691
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