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Revision 1.13 by elmex, Thu May 15 13:32:19 2008 UTC vs.
Revision 1.159 by root, Fri Jul 24 12:35:58 2009 UTC

1package AnyEvent::Handle; 1package AnyEvent::Handle;
2 2
3no warnings;
4use strict;
5
6use AnyEvent ();
7use AnyEvent::Util ();
8use Scalar::Util (); 3use Scalar::Util ();
9use Carp (); 4use Carp ();
10use Fcntl ();
11use Errno qw/EAGAIN EINTR/; 5use Errno qw(EAGAIN EINTR);
6
7use AnyEvent (); BEGIN { AnyEvent::common_sense }
8use AnyEvent::Util qw(WSAEWOULDBLOCK);
12 9
13=head1 NAME 10=head1 NAME
14 11
15AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent 12AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 13
17=cut 14=cut
18 15
19our $VERSION = '0.02'; 16our $VERSION = 4.86;
20 17
21=head1 SYNOPSIS 18=head1 SYNOPSIS
22 19
23 use AnyEvent; 20 use AnyEvent;
24 use AnyEvent::Handle; 21 use AnyEvent::Handle;
25 22
26 my $cv = AnyEvent->condvar; 23 my $cv = AnyEvent->condvar;
27 24
28 my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN); 25 my $hdl; $hdl = new AnyEvent::Handle
29
30 #TODO
31
32 # or use the constructor to pass the callback:
33
34 my $ae_fh2 =
35 AnyEvent::Handle->new (
36 fh => \*STDIN, 26 fh => \*STDIN,
37 on_eof => sub { 27 on_error => sub {
38 $cv->broadcast; 28 my ($hdl, $fatal, $msg) = @_;
39 }, 29 warn "got error $msg\n";
40 #TODO 30 $hdl->destroy;
31 $cv->send;
41 ); 32 );
42 33
43 $cv->wait; 34 # send some request line
35 $hdl->push_write ("getinfo\015\012");
36
37 # read the response line
38 $hdl->push_read (line => sub {
39 my ($hdl, $line) = @_;
40 warn "got line <$line>\n";
41 $cv->send;
42 });
43
44 $cv->recv;
44 45
45=head1 DESCRIPTION 46=head1 DESCRIPTION
46 47
47This module is a helper module to make it easier to do event-based I/O on 48This module is a helper module to make it easier to do event-based I/O on
48filehandles. For utility functions for doing non-blocking connects and accepts 49filehandles.
49on sockets see L<AnyEvent::Util>. 50
51The L<AnyEvent::Intro> tutorial contains some well-documented
52AnyEvent::Handle examples.
50 53
51In the following, when the documentation refers to of "bytes" then this 54In the following, when the documentation refers to of "bytes" then this
52means characters. As sysread and syswrite are used for all I/O, their 55means characters. As sysread and syswrite are used for all I/O, their
53treatment of characters applies to this module as well. 56treatment of characters applies to this module as well.
54 57
58At the very minimum, you should specify C<fh> or C<connect>, and the
59C<on_error> callback.
60
55All callbacks will be invoked with the handle object as their first 61All callbacks will be invoked with the handle object as their first
56argument. 62argument.
57 63
58=head1 METHODS 64=head1 METHODS
59 65
60=over 4 66=over 4
61 67
62=item B<new (%args)> 68=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
63 69
64The constructor supports these arguments (all as key => value pairs). 70The constructor supports these arguments (all as C<< key => value >> pairs).
65 71
66=over 4 72=over 4
67 73
68=item fh => $filehandle [MANDATORY] 74=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
69 75
70The filehandle this L<AnyEvent::Handle> object will operate on. 76The filehandle this L<AnyEvent::Handle> object will operate on.
71
72NOTE: The filehandle will be set to non-blocking (using 77NOTE: The filehandle will be set to non-blocking mode (using
73AnyEvent::Util::fh_nonblocking). 78C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
79that mode.
74 80
75=item on_eof => $cb->($self) [MANDATORY] 81=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
76 82
77Set the callback to be called on EOF. 83Try to connect to the specified host and service (port), using
84C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
85default C<peername>.
78 86
87You have to specify either this parameter, or C<fh>, above.
88
89When this parameter is specified, then the C<on_prepare>,
90C<on_connect_error> and C<on_connect> callbacks will be called under the
91appropriate circumstances:
92
93=over 4
94
79=item on_error => $cb->($self) 95=item on_prepare => $cb->($handle)
80 96
97This (rarely used) callback is called before a new connection is
98attempted, but after the file handle has been created. It could be used to
99prepare the file handle with parameters required for the actual connect
100(as opposed to settings that can be changed when the connection is already
101established).
102
103=item on_connect => $cb->($handle, $host, $port, $retry->())
104
105This callback is called when a connection has been successfully established.
106
107The actual numeric host and port (the socket peername) are passed as
108parameters, together with a retry callback.
109
110When, for some reason, the handle is not acceptable, then calling
111C<$retry> will continue with the next conenction target (in case of
112multi-homed hosts or SRV records there can be multiple connection
113endpoints). When it is called then the read and write queues, eof status,
114tls status and similar properties of the handle are being reset.
115
116In most cases, ignoring the C<$retry> parameter is the way to go.
117
118=item on_connect_error => $cb->($handle, $message)
119
120This callback is called when the conenction could not be
121established. C<$!> will contain the relevant error code, and C<$message> a
122message describing it (usually the same as C<"$!">).
123
124If this callback isn't specified, then C<on_error> will be called with a
125fatal error instead.
126
127=back
128
129=item on_error => $cb->($handle, $fatal, $message)
130
81This is the fatal error callback, that is called when, well, a fatal error 131This is the error callback, which is called when, well, some error
82ocurs, such as not being able to resolve the hostname, failure to connect 132occured, such as not being able to resolve the hostname, failure to
83or a read error. 133connect or a read error.
84 134
85The object will not be in a usable state when this callback has been 135Some errors are fatal (which is indicated by C<$fatal> being true). On
86called. 136fatal errors the handle object will be destroyed (by a call to C<< ->
137destroy >>) after invoking the error callback (which means you are free to
138examine the handle object). Examples of fatal errors are an EOF condition
139with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In
140cases where the other side can close the connection at their will it is
141often easiest to not report C<EPIPE> errors in this callback.
142
143AnyEvent::Handle tries to find an appropriate error code for you to check
144against, but in some cases (TLS errors), this does not work well. It is
145recommended to always output the C<$message> argument in human-readable
146error messages (it's usually the same as C<"$!">).
147
148Non-fatal errors can be retried by simply returning, but it is recommended
149to simply ignore this parameter and instead abondon the handle object
150when this callback is invoked. Examples of non-fatal errors are timeouts
151C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
87 152
88On callback entrance, the value of C<$!> contains the operating system 153On callback entrance, the value of C<$!> contains the operating system
89error (or C<ENOSPC> or C<EPIPE>). 154error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
155C<EPROTO>).
90 156
91While not mandatory, it is I<highly> recommended to set this callback, as 157While not mandatory, it is I<highly> recommended to set this callback, as
92you will not be notified of errors otherwise. The default simply calls 158you will not be notified of errors otherwise. The default simply calls
93die. 159C<croak>.
94 160
95=item on_read => $cb->($self) 161=item on_read => $cb->($handle)
96 162
97This sets the default read callback, which is called when data arrives 163This sets the default read callback, which is called when data arrives
98and no read request is in the queue. 164and no read request is in the queue (unlike read queue callbacks, this
165callback will only be called when at least one octet of data is in the
166read buffer).
99 167
100To access (and remove data from) the read buffer, use the C<< ->rbuf >> 168To access (and remove data from) the read buffer, use the C<< ->rbuf >>
101method or acces sthe C<$self->{rbuf}> member directly. 169method or access the C<< $handle->{rbuf} >> member directly. Note that you
170must not enlarge or modify the read buffer, you can only remove data at
171the beginning from it.
102 172
103When an EOF condition is detected then AnyEvent::Handle will first try to 173When an EOF condition is detected then AnyEvent::Handle will first try to
104feed all the remaining data to the queued callbacks and C<on_read> before 174feed all the remaining data to the queued callbacks and C<on_read> before
105calling the C<on_eof> callback. If no progress can be made, then a fatal 175calling the C<on_eof> callback. If no progress can be made, then a fatal
106error will be raised (with C<$!> set to C<EPIPE>). 176error will be raised (with C<$!> set to C<EPIPE>).
107 177
178Note that, unlike requests in the read queue, an C<on_read> callback
179doesn't mean you I<require> some data: if there is an EOF and there
180are outstanding read requests then an error will be flagged. With an
181C<on_read> callback, the C<on_eof> callback will be invoked.
182
183=item on_eof => $cb->($handle)
184
185Set the callback to be called when an end-of-file condition is detected,
186i.e. in the case of a socket, when the other side has closed the
187connection cleanly, and there are no outstanding read requests in the
188queue (if there are read requests, then an EOF counts as an unexpected
189connection close and will be flagged as an error).
190
191For sockets, this just means that the other side has stopped sending data,
192you can still try to write data, and, in fact, one can return from the EOF
193callback and continue writing data, as only the read part has been shut
194down.
195
196If an EOF condition has been detected but no C<on_eof> callback has been
197set, then a fatal error will be raised with C<$!> set to <0>.
198
108=item on_drain => $cb->() 199=item on_drain => $cb->($handle)
109 200
110This sets the callback that is called when the write buffer becomes empty 201This sets the callback that is called when the write buffer becomes empty
111(or when the callback is set and the buffer is empty already). 202(or when the callback is set and the buffer is empty already).
112 203
113To append to the write buffer, use the C<< ->push_write >> method. 204To append to the write buffer, use the C<< ->push_write >> method.
114 205
206This callback is useful when you don't want to put all of your write data
207into the queue at once, for example, when you want to write the contents
208of some file to the socket you might not want to read the whole file into
209memory and push it into the queue, but instead only read more data from
210the file when the write queue becomes empty.
211
212=item timeout => $fractional_seconds
213
214If non-zero, then this enables an "inactivity" timeout: whenever this many
215seconds pass without a successful read or write on the underlying file
216handle, the C<on_timeout> callback will be invoked (and if that one is
217missing, a non-fatal C<ETIMEDOUT> error will be raised).
218
219Note that timeout processing is also active when you currently do not have
220any outstanding read or write requests: If you plan to keep the connection
221idle then you should disable the timout temporarily or ignore the timeout
222in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
223restart the timeout.
224
225Zero (the default) disables this timeout.
226
227=item on_timeout => $cb->($handle)
228
229Called whenever the inactivity timeout passes. If you return from this
230callback, then the timeout will be reset as if some activity had happened,
231so this condition is not fatal in any way.
232
115=item rbuf_max => <bytes> 233=item rbuf_max => <bytes>
116 234
117If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 235If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
118when the read buffer ever (strictly) exceeds this size. This is useful to 236when the read buffer ever (strictly) exceeds this size. This is useful to
119avoid denial-of-service attacks. 237avoid some forms of denial-of-service attacks.
120 238
121For example, a server accepting connections from untrusted sources should 239For example, a server accepting connections from untrusted sources should
122be configured to accept only so-and-so much data that it cannot act on 240be configured to accept only so-and-so much data that it cannot act on
123(for example, when expecting a line, an attacker could send an unlimited 241(for example, when expecting a line, an attacker could send an unlimited
124amount of data without a callback ever being called as long as the line 242amount of data without a callback ever being called as long as the line
125isn't finished). 243isn't finished).
126 244
245=item autocork => <boolean>
246
247When disabled (the default), then C<push_write> will try to immediately
248write the data to the handle, if possible. This avoids having to register
249a write watcher and wait for the next event loop iteration, but can
250be inefficient if you write multiple small chunks (on the wire, this
251disadvantage is usually avoided by your kernel's nagle algorithm, see
252C<no_delay>, but this option can save costly syscalls).
253
254When enabled, then writes will always be queued till the next event loop
255iteration. This is efficient when you do many small writes per iteration,
256but less efficient when you do a single write only per iteration (or when
257the write buffer often is full). It also increases write latency.
258
259=item no_delay => <boolean>
260
261When doing small writes on sockets, your operating system kernel might
262wait a bit for more data before actually sending it out. This is called
263the Nagle algorithm, and usually it is beneficial.
264
265In some situations you want as low a delay as possible, which can be
266accomplishd by setting this option to a true value.
267
268The default is your opertaing system's default behaviour (most likely
269enabled), this option explicitly enables or disables it, if possible.
270
127=item read_size => <bytes> 271=item read_size => <bytes>
128 272
129The default read block size (the amount of bytes this module will try to read 273The default read block size (the amount of bytes this module will
130on each [loop iteration). Default: C<4096>. 274try to read during each loop iteration, which affects memory
275requirements). Default: C<8192>.
131 276
132=item low_water_mark => <bytes> 277=item low_water_mark => <bytes>
133 278
134Sets the amount of bytes (default: C<0>) that make up an "empty" write 279Sets the amount of bytes (default: C<0>) that make up an "empty" write
135buffer: If the write reaches this size or gets even samller it is 280buffer: If the write reaches this size or gets even samller it is
136considered empty. 281considered empty.
137 282
283Sometimes it can be beneficial (for performance reasons) to add data to
284the write buffer before it is fully drained, but this is a rare case, as
285the operating system kernel usually buffers data as well, so the default
286is good in almost all cases.
287
288=item linger => <seconds>
289
290If non-zero (default: C<3600>), then the destructor of the
291AnyEvent::Handle object will check whether there is still outstanding
292write data and will install a watcher that will write this data to the
293socket. No errors will be reported (this mostly matches how the operating
294system treats outstanding data at socket close time).
295
296This will not work for partial TLS data that could not be encoded
297yet. This data will be lost. Calling the C<stoptls> method in time might
298help.
299
300=item peername => $string
301
302A string used to identify the remote site - usually the DNS hostname
303(I<not> IDN!) used to create the connection, rarely the IP address.
304
305Apart from being useful in error messages, this string is also used in TLS
306peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
307verification will be skipped when C<peername> is not specified or
308C<undef>.
309
310=item tls => "accept" | "connect" | Net::SSLeay::SSL object
311
312When this parameter is given, it enables TLS (SSL) mode, that means
313AnyEvent will start a TLS handshake as soon as the conenction has been
314established and will transparently encrypt/decrypt data afterwards.
315
316All TLS protocol errors will be signalled as C<EPROTO>, with an
317appropriate error message.
318
319TLS mode requires Net::SSLeay to be installed (it will be loaded
320automatically when you try to create a TLS handle): this module doesn't
321have a dependency on that module, so if your module requires it, you have
322to add the dependency yourself.
323
324Unlike TCP, TLS has a server and client side: for the TLS server side, use
325C<accept>, and for the TLS client side of a connection, use C<connect>
326mode.
327
328You can also provide your own TLS connection object, but you have
329to make sure that you call either C<Net::SSLeay::set_connect_state>
330or C<Net::SSLeay::set_accept_state> on it before you pass it to
331AnyEvent::Handle. Also, this module will take ownership of this connection
332object.
333
334At some future point, AnyEvent::Handle might switch to another TLS
335implementation, then the option to use your own session object will go
336away.
337
338B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
339passing in the wrong integer will lead to certain crash. This most often
340happens when one uses a stylish C<< tls => 1 >> and is surprised about the
341segmentation fault.
342
343See the C<< ->starttls >> method for when need to start TLS negotiation later.
344
345=item tls_ctx => $anyevent_tls
346
347Use the given C<AnyEvent::TLS> object to create the new TLS connection
348(unless a connection object was specified directly). If this parameter is
349missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
350
351Instead of an object, you can also specify a hash reference with C<< key
352=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
353new TLS context object.
354
355=item on_starttls => $cb->($handle, $success[, $error_message])
356
357This callback will be invoked when the TLS/SSL handshake has finished. If
358C<$success> is true, then the TLS handshake succeeded, otherwise it failed
359(C<on_stoptls> will not be called in this case).
360
361The session in C<< $handle->{tls} >> can still be examined in this
362callback, even when the handshake was not successful.
363
364TLS handshake failures will not cause C<on_error> to be invoked when this
365callback is in effect, instead, the error message will be passed to C<on_starttls>.
366
367Without this callback, handshake failures lead to C<on_error> being
368called, as normal.
369
370Note that you cannot call C<starttls> right again in this callback. If you
371need to do that, start an zero-second timer instead whose callback can
372then call C<< ->starttls >> again.
373
374=item on_stoptls => $cb->($handle)
375
376When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
377set, then it will be invoked after freeing the TLS session. If it is not,
378then a TLS shutdown condition will be treated like a normal EOF condition
379on the handle.
380
381The session in C<< $handle->{tls} >> can still be examined in this
382callback.
383
384This callback will only be called on TLS shutdowns, not when the
385underlying handle signals EOF.
386
387=item json => JSON or JSON::XS object
388
389This is the json coder object used by the C<json> read and write types.
390
391If you don't supply it, then AnyEvent::Handle will create and use a
392suitable one (on demand), which will write and expect UTF-8 encoded JSON
393texts.
394
395Note that you are responsible to depend on the JSON module if you want to
396use this functionality, as AnyEvent does not have a dependency itself.
397
138=back 398=back
139 399
140=cut 400=cut
141 401
142sub new { 402sub new {
143 my $class = shift; 403 my $class = shift;
144
145 my $self = bless { @_ }, $class; 404 my $self = bless { @_ }, $class;
146 405
147 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 406 if ($self->{fh}) {
407 $self->_start;
408 return unless $self->{fh}; # could be gone by now
409
410 } elsif ($self->{connect}) {
411 require AnyEvent::Socket;
412
413 $self->{peername} = $self->{connect}[0]
414 unless exists $self->{peername};
415
416 $self->{_skip_drain_rbuf} = 1;
417
418 {
419 Scalar::Util::weaken (my $self = $self);
420
421 $self->{_connect} =
422 AnyEvent::Socket::tcp_connect (
423 $self->{connect}[0],
424 $self->{connect}[1],
425 sub {
426 my ($fh, $host, $port, $retry) = @_;
427
428 if ($fh) {
429 $self->{fh} = $fh;
430
431 delete $self->{_skip_drain_rbuf};
432 $self->_start;
433
434 $self->{on_connect}
435 and $self->{on_connect}($self, $host, $port, sub {
436 delete @$self{qw(fh _tw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
437 $self->{_skip_drain_rbuf} = 1;
438 &$retry;
439 });
440
441 } else {
442 if ($self->{on_connect_error}) {
443 $self->{on_connect_error}($self, "$!");
444 $self->destroy;
445 } else {
446 $self->fatal ($!, 1);
447 }
448 }
449 },
450 sub {
451 local $self->{fh} = $_[0];
452
453 $self->{on_prepare}->($self)
454 if $self->{on_prepare};
455 }
456 );
457 }
458
459 } else {
460 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
461 }
462
463 $self
464}
465
466sub _start {
467 my ($self) = @_;
148 468
149 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 469 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
150 470
151 $self->on_eof ((delete $self->{on_eof} ) or Carp::croak "mandatory argument on_eof is missing"); 471 $self->{_activity} = AnyEvent->now;
472 $self->_timeout;
152 473
153 $self->on_error (delete $self->{on_error}) if $self->{on_error}; 474 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
475
476 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
477 if $self->{tls};
478
154 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 479 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
155 $self->on_read (delete $self->{on_read} ) if $self->{on_read};
156 480
157 $self->start_read; 481 $self->start_read
158 482 if $self->{on_read} || @{ $self->{_queue} };
159 $self
160} 483}
161 484
162sub _shutdown { 485#sub _shutdown {
163 my ($self) = @_; 486# my ($self) = @_;
487#
488# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
489# $self->{_eof} = 1; # tell starttls et. al to stop trying
490#
491# &_freetls;
492#}
164 493
165 delete $self->{rw};
166 delete $self->{ww};
167 delete $self->{fh};
168}
169
170sub error { 494sub _error {
171 my ($self) = @_; 495 my ($self, $errno, $fatal, $message) = @_;
172 496
173 { 497 $! = $errno;
174 local $!; 498 $message ||= "$!";
175 $self->_shutdown;
176 }
177 499
178 if ($self->{on_error}) { 500 if ($self->{on_error}) {
179 $self->{on_error}($self); 501 $self->{on_error}($self, $fatal, $message);
180 } else { 502 $self->destroy if $fatal;
503 } elsif ($self->{fh}) {
504 $self->destroy;
181 die "AnyEvent::Handle uncaught fatal error: $!"; 505 Carp::croak "AnyEvent::Handle uncaught error: $message";
182 } 506 }
183} 507}
184 508
185=item $fh = $handle->fh 509=item $fh = $handle->fh
186 510
187This method returns the filehandle of the L<AnyEvent::Handle> object. 511This method returns the file handle used to create the L<AnyEvent::Handle> object.
188 512
189=cut 513=cut
190 514
191sub fh { $_[0]->{fh} } 515sub fh { $_[0]{fh} }
192 516
193=item $handle->on_error ($cb) 517=item $handle->on_error ($cb)
194 518
195Replace the current C<on_error> callback (see the C<on_error> constructor argument). 519Replace the current C<on_error> callback (see the C<on_error> constructor argument).
196 520
208 532
209sub on_eof { 533sub on_eof {
210 $_[0]{on_eof} = $_[1]; 534 $_[0]{on_eof} = $_[1];
211} 535}
212 536
537=item $handle->on_timeout ($cb)
538
539Replace the current C<on_timeout> callback, or disables the callback (but
540not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
541argument and method.
542
543=cut
544
545sub on_timeout {
546 $_[0]{on_timeout} = $_[1];
547}
548
549=item $handle->autocork ($boolean)
550
551Enables or disables the current autocork behaviour (see C<autocork>
552constructor argument). Changes will only take effect on the next write.
553
554=cut
555
556sub autocork {
557 $_[0]{autocork} = $_[1];
558}
559
560=item $handle->no_delay ($boolean)
561
562Enables or disables the C<no_delay> setting (see constructor argument of
563the same name for details).
564
565=cut
566
567sub no_delay {
568 $_[0]{no_delay} = $_[1];
569
570 eval {
571 local $SIG{__DIE__};
572 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]
573 if $_[0]{fh};
574 };
575}
576
577=item $handle->on_starttls ($cb)
578
579Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
580
581=cut
582
583sub on_starttls {
584 $_[0]{on_starttls} = $_[1];
585}
586
587=item $handle->on_stoptls ($cb)
588
589Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
590
591=cut
592
593sub on_starttls {
594 $_[0]{on_stoptls} = $_[1];
595}
596
597#############################################################################
598
599=item $handle->timeout ($seconds)
600
601Configures (or disables) the inactivity timeout.
602
603=cut
604
605sub timeout {
606 my ($self, $timeout) = @_;
607
608 $self->{timeout} = $timeout;
609 $self->_timeout;
610}
611
612# reset the timeout watcher, as neccessary
613# also check for time-outs
614sub _timeout {
615 my ($self) = @_;
616
617 if ($self->{timeout} && $self->{fh}) {
618 my $NOW = AnyEvent->now;
619
620 # when would the timeout trigger?
621 my $after = $self->{_activity} + $self->{timeout} - $NOW;
622
623 # now or in the past already?
624 if ($after <= 0) {
625 $self->{_activity} = $NOW;
626
627 if ($self->{on_timeout}) {
628 $self->{on_timeout}($self);
629 } else {
630 $self->_error (Errno::ETIMEDOUT);
631 }
632
633 # callback could have changed timeout value, optimise
634 return unless $self->{timeout};
635
636 # calculate new after
637 $after = $self->{timeout};
638 }
639
640 Scalar::Util::weaken $self;
641 return unless $self; # ->error could have destroyed $self
642
643 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
644 delete $self->{_tw};
645 $self->_timeout;
646 });
647 } else {
648 delete $self->{_tw};
649 }
650}
651
213############################################################################# 652#############################################################################
214 653
215=back 654=back
216 655
217=head2 WRITE QUEUE 656=head2 WRITE QUEUE
220for reading. 659for reading.
221 660
222The write queue is very simple: you can add data to its end, and 661The write queue is very simple: you can add data to its end, and
223AnyEvent::Handle will automatically try to get rid of it for you. 662AnyEvent::Handle will automatically try to get rid of it for you.
224 663
225When data could be writtena nd the write buffer is shorter then the low 664When data could be written and the write buffer is shorter then the low
226water mark, the C<on_drain> callback will be invoked. 665water mark, the C<on_drain> callback will be invoked.
227 666
228=over 4 667=over 4
229 668
230=item $handle->on_drain ($cb) 669=item $handle->on_drain ($cb)
238 my ($self, $cb) = @_; 677 my ($self, $cb) = @_;
239 678
240 $self->{on_drain} = $cb; 679 $self->{on_drain} = $cb;
241 680
242 $cb->($self) 681 $cb->($self)
243 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 682 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
244} 683}
245 684
246=item $handle->push_write ($data) 685=item $handle->push_write ($data)
247 686
248Queues the given scalar to be written. You can push as much data as you 687Queues the given scalar to be written. You can push as much data as you
249want (only limited by the available memory), as C<AnyEvent::Handle> 688want (only limited by the available memory), as C<AnyEvent::Handle>
250buffers it independently of the kernel. 689buffers it independently of the kernel.
251 690
252=cut 691=cut
253 692
254sub push_write { 693sub _drain_wbuf {
255 my ($self, $data) = @_; 694 my ($self) = @_;
256 695
257 $self->{wbuf} .= $data; 696 if (!$self->{_ww} && length $self->{wbuf}) {
258 697
259 unless ($self->{ww}) {
260 Scalar::Util::weaken $self; 698 Scalar::Util::weaken $self;
699
261 my $cb = sub { 700 my $cb = sub {
262 my $len = syswrite $self->{fh}, $self->{wbuf}; 701 my $len = syswrite $self->{fh}, $self->{wbuf};
263 702
264 if ($len > 0) { 703 if (defined $len) {
265 substr $self->{wbuf}, 0, $len, ""; 704 substr $self->{wbuf}, 0, $len, "";
266 705
706 $self->{_activity} = AnyEvent->now;
267 707
268 $self->{on_drain}($self) 708 $self->{on_drain}($self)
269 if $self->{low_water_mark} >= length $self->{wbuf} 709 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
270 && $self->{on_drain}; 710 && $self->{on_drain};
271 711
272 delete $self->{ww} unless length $self->{wbuf}; 712 delete $self->{_ww} unless length $self->{wbuf};
273 } elsif ($! != EAGAIN && $! != EINTR) { 713 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
274 $self->error; 714 $self->_error ($!, 1);
275 } 715 }
276 }; 716 };
277 717
718 # try to write data immediately
719 $cb->() unless $self->{autocork};
720
721 # if still data left in wbuf, we need to poll
278 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb); 722 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
279 723 if length $self->{wbuf};
280 $cb->($self);
281 }; 724 };
282} 725}
726
727our %WH;
728
729sub register_write_type($$) {
730 $WH{$_[0]} = $_[1];
731}
732
733sub push_write {
734 my $self = shift;
735
736 if (@_ > 1) {
737 my $type = shift;
738
739 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
740 ->($self, @_);
741 }
742
743 if ($self->{tls}) {
744 $self->{_tls_wbuf} .= $_[0];
745
746 &_dotls ($self);
747 } else {
748 $self->{wbuf} .= $_[0];
749 $self->_drain_wbuf if $self->{fh};
750 }
751}
752
753=item $handle->push_write (type => @args)
754
755Instead of formatting your data yourself, you can also let this module do
756the job by specifying a type and type-specific arguments.
757
758Predefined types are (if you have ideas for additional types, feel free to
759drop by and tell us):
760
761=over 4
762
763=item netstring => $string
764
765Formats the given value as netstring
766(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
767
768=cut
769
770register_write_type netstring => sub {
771 my ($self, $string) = @_;
772
773 (length $string) . ":$string,"
774};
775
776=item packstring => $format, $data
777
778An octet string prefixed with an encoded length. The encoding C<$format>
779uses the same format as a Perl C<pack> format, but must specify a single
780integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
781optional C<!>, C<< < >> or C<< > >> modifier).
782
783=cut
784
785register_write_type packstring => sub {
786 my ($self, $format, $string) = @_;
787
788 pack "$format/a*", $string
789};
790
791=item json => $array_or_hashref
792
793Encodes the given hash or array reference into a JSON object. Unless you
794provide your own JSON object, this means it will be encoded to JSON text
795in UTF-8.
796
797JSON objects (and arrays) are self-delimiting, so you can write JSON at
798one end of a handle and read them at the other end without using any
799additional framing.
800
801The generated JSON text is guaranteed not to contain any newlines: While
802this module doesn't need delimiters after or between JSON texts to be
803able to read them, many other languages depend on that.
804
805A simple RPC protocol that interoperates easily with others is to send
806JSON arrays (or objects, although arrays are usually the better choice as
807they mimic how function argument passing works) and a newline after each
808JSON text:
809
810 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
811 $handle->push_write ("\012");
812
813An AnyEvent::Handle receiver would simply use the C<json> read type and
814rely on the fact that the newline will be skipped as leading whitespace:
815
816 $handle->push_read (json => sub { my $array = $_[1]; ... });
817
818Other languages could read single lines terminated by a newline and pass
819this line into their JSON decoder of choice.
820
821=cut
822
823register_write_type json => sub {
824 my ($self, $ref) = @_;
825
826 require JSON;
827
828 $self->{json} ? $self->{json}->encode ($ref)
829 : JSON::encode_json ($ref)
830};
831
832=item storable => $reference
833
834Freezes the given reference using L<Storable> and writes it to the
835handle. Uses the C<nfreeze> format.
836
837=cut
838
839register_write_type storable => sub {
840 my ($self, $ref) = @_;
841
842 require Storable;
843
844 pack "w/a*", Storable::nfreeze ($ref)
845};
846
847=back
848
849=item $handle->push_shutdown
850
851Sometimes you know you want to close the socket after writing your data
852before it was actually written. One way to do that is to replace your
853C<on_drain> handler by a callback that shuts down the socket (and set
854C<low_water_mark> to C<0>). This method is a shorthand for just that, and
855replaces the C<on_drain> callback with:
856
857 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
858
859This simply shuts down the write side and signals an EOF condition to the
860the peer.
861
862You can rely on the normal read queue and C<on_eof> handling
863afterwards. This is the cleanest way to close a connection.
864
865=cut
866
867sub push_shutdown {
868 my ($self) = @_;
869
870 delete $self->{low_water_mark};
871 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
872}
873
874=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
875
876This function (not method) lets you add your own types to C<push_write>.
877Whenever the given C<type> is used, C<push_write> will invoke the code
878reference with the handle object and the remaining arguments.
879
880The code reference is supposed to return a single octet string that will
881be appended to the write buffer.
882
883Note that this is a function, and all types registered this way will be
884global, so try to use unique names.
885
886=cut
283 887
284############################################################################# 888#############################################################################
285 889
286=back 890=back
287 891
294ways, the "simple" way, using only C<on_read> and the "complex" way, using 898ways, the "simple" way, using only C<on_read> and the "complex" way, using
295a queue. 899a queue.
296 900
297In the simple case, you just install an C<on_read> callback and whenever 901In the simple case, you just install an C<on_read> callback and whenever
298new data arrives, it will be called. You can then remove some data (if 902new data arrives, it will be called. You can then remove some data (if
299enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 903enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
300or not. 904leave the data there if you want to accumulate more (e.g. when only a
905partial message has been received so far).
301 906
302In the more complex case, you want to queue multiple callbacks. In this 907In the more complex case, you want to queue multiple callbacks. In this
303case, AnyEvent::Handle will call the first queued callback each time new 908case, AnyEvent::Handle will call the first queued callback each time new
304data arrives and removes it when it has done its job (see C<push_read>, 909data arrives (also the first time it is queued) and removes it when it has
305below). 910done its job (see C<push_read>, below).
306 911
307This way you can, for example, push three line-reads, followed by reading 912This way you can, for example, push three line-reads, followed by reading
308a chunk of data, and AnyEvent::Handle will execute them in order. 913a chunk of data, and AnyEvent::Handle will execute them in order.
309 914
310Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 915Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
311the specified number of bytes which give an XML datagram. 916the specified number of bytes which give an XML datagram.
312 917
313 # in the default state, expect some header bytes 918 # in the default state, expect some header bytes
314 $handle->on_read (sub { 919 $handle->on_read (sub {
315 # some data is here, now queue the length-header-read (4 octets) 920 # some data is here, now queue the length-header-read (4 octets)
316 shift->unshift_read_chunk (4, sub { 921 shift->unshift_read (chunk => 4, sub {
317 # header arrived, decode 922 # header arrived, decode
318 my $len = unpack "N", $_[1]; 923 my $len = unpack "N", $_[1];
319 924
320 # now read the payload 925 # now read the payload
321 shift->unshift_read_chunk ($len, sub { 926 shift->unshift_read (chunk => $len, sub {
322 my $xml = $_[1]; 927 my $xml = $_[1];
323 # handle xml 928 # handle xml
324 }); 929 });
325 }); 930 });
326 }); 931 });
327 932
328Example 2: Implement a client for a protocol that replies either with 933Example 2: Implement a client for a protocol that replies either with "OK"
329"OK" and another line or "ERROR" for one request, and 64 bytes for the 934and another line or "ERROR" for the first request that is sent, and 64
330second request. Due tot he availability of a full queue, we can just 935bytes for the second request. Due to the availability of a queue, we can
331pipeline sending both requests and manipulate the queue as necessary in 936just pipeline sending both requests and manipulate the queue as necessary
332the callbacks: 937in the callbacks.
333 938
334 # request one 939When the first callback is called and sees an "OK" response, it will
940C<unshift> another line-read. This line-read will be queued I<before> the
94164-byte chunk callback.
942
943 # request one, returns either "OK + extra line" or "ERROR"
335 $handle->push_write ("request 1\015\012"); 944 $handle->push_write ("request 1\015\012");
336 945
337 # we expect "ERROR" or "OK" as response, so push a line read 946 # we expect "ERROR" or "OK" as response, so push a line read
338 $handle->push_read_line (sub { 947 $handle->push_read (line => sub {
339 # if we got an "OK", we have to _prepend_ another line, 948 # if we got an "OK", we have to _prepend_ another line,
340 # so it will be read before the second request reads its 64 bytes 949 # so it will be read before the second request reads its 64 bytes
341 # which are already in the queue when this callback is called 950 # which are already in the queue when this callback is called
342 # we don't do this in case we got an error 951 # we don't do this in case we got an error
343 if ($_[1] eq "OK") { 952 if ($_[1] eq "OK") {
344 $_[0]->unshift_read_line (sub { 953 $_[0]->unshift_read (line => sub {
345 my $response = $_[1]; 954 my $response = $_[1];
346 ... 955 ...
347 }); 956 });
348 } 957 }
349 }); 958 });
350 959
351 # request two 960 # request two, simply returns 64 octets
352 $handle->push_write ("request 2\015\012"); 961 $handle->push_write ("request 2\015\012");
353 962
354 # simply read 64 bytes, always 963 # simply read 64 bytes, always
355 $handle->push_read_chunk (64, sub { 964 $handle->push_read (chunk => 64, sub {
356 my $response = $_[1]; 965 my $response = $_[1];
357 ... 966 ...
358 }); 967 });
359 968
360=over 4 969=over 4
362=cut 971=cut
363 972
364sub _drain_rbuf { 973sub _drain_rbuf {
365 my ($self) = @_; 974 my ($self) = @_;
366 975
976 # avoid recursion
367 return if $self->{in_drain}; 977 return if exists $self->{_skip_drain_rbuf};
368 local $self->{in_drain} = 1; 978 local $self->{_skip_drain_rbuf} = 1;
369 979
980 if (
981 defined $self->{rbuf_max}
982 && $self->{rbuf_max} < length $self->{rbuf}
983 ) {
984 $self->_error (Errno::ENOSPC, 1), return;
985 }
986
987 while () {
988 # we need to use a separate tls read buffer, as we must not receive data while
989 # we are draining the buffer, and this can only happen with TLS.
990 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
991
370 while (my $len = length $self->{rbuf}) { 992 my $len = length $self->{rbuf};
371 no strict 'refs'; 993
372 if (my $cb = shift @{ $self->{queue} }) { 994 if (my $cb = shift @{ $self->{_queue} }) {
373 if (!$cb->($self)) { 995 unless ($cb->($self)) {
374 if ($self->{eof}) { 996 if ($self->{_eof}) {
375 # no progress can be made (not enough data and no data forthcoming) 997 # no progress can be made (not enough data and no data forthcoming)
376 $! = &Errno::EPIPE; return $self->error; 998 $self->_error (Errno::EPIPE, 1), return;
377 } 999 }
378 1000
379 unshift @{ $self->{queue} }, $cb; 1001 unshift @{ $self->{_queue} }, $cb;
380 return; 1002 last;
381 } 1003 }
382 } elsif ($self->{on_read}) { 1004 } elsif ($self->{on_read}) {
1005 last unless $len;
1006
383 $self->{on_read}($self); 1007 $self->{on_read}($self);
384 1008
385 if ( 1009 if (
386 $self->{eof} # if no further data will arrive
387 && $len == length $self->{rbuf} # and no data has been consumed 1010 $len == length $self->{rbuf} # if no data has been consumed
388 && !@{ $self->{queue} } # and the queue is still empty 1011 && !@{ $self->{_queue} } # and the queue is still empty
389 && $self->{on_read} # and we still want to read data 1012 && $self->{on_read} # but we still have on_read
390 ) { 1013 ) {
1014 # no further data will arrive
391 # then no progress can be made 1015 # so no progress can be made
392 $! = &Errno::EPIPE; return $self->error; 1016 $self->_error (Errno::EPIPE, 1), return
1017 if $self->{_eof};
1018
1019 last; # more data might arrive
393 } 1020 }
394 } else { 1021 } else {
395 # read side becomes idle 1022 # read side becomes idle
396 delete $self->{rw}; 1023 delete $self->{_rw} unless $self->{tls};
397 return; 1024 last;
398 } 1025 }
399 } 1026 }
400 1027
401 if ($self->{eof}) { 1028 if ($self->{_eof}) {
402 $self->_shutdown; 1029 if ($self->{on_eof}) {
403 $self->{on_eof}($self); 1030 $self->{on_eof}($self)
1031 } else {
1032 $self->_error (0, 1, "Unexpected end-of-file");
1033 }
1034 }
1035
1036 # may need to restart read watcher
1037 unless ($self->{_rw}) {
1038 $self->start_read
1039 if $self->{on_read} || @{ $self->{_queue} };
404 } 1040 }
405} 1041}
406 1042
407=item $handle->on_read ($cb) 1043=item $handle->on_read ($cb)
408 1044
414 1050
415sub on_read { 1051sub on_read {
416 my ($self, $cb) = @_; 1052 my ($self, $cb) = @_;
417 1053
418 $self->{on_read} = $cb; 1054 $self->{on_read} = $cb;
1055 $self->_drain_rbuf if $cb;
419} 1056}
420 1057
421=item $handle->rbuf 1058=item $handle->rbuf
422 1059
423Returns the read buffer (as a modifiable lvalue). 1060Returns the read buffer (as a modifiable lvalue).
424 1061
425You can access the read buffer directly as the C<< ->{rbuf} >> member, if 1062You can access the read buffer directly as the C<< ->{rbuf} >>
426you want. 1063member, if you want. However, the only operation allowed on the
1064read buffer (apart from looking at it) is removing data from its
1065beginning. Otherwise modifying or appending to it is not allowed and will
1066lead to hard-to-track-down bugs.
427 1067
428NOTE: The read buffer should only be used or modified if the C<on_read>, 1068NOTE: The read buffer should only be used or modified if the C<on_read>,
429C<push_read> or C<unshift_read> methods are used. The other read methods 1069C<push_read> or C<unshift_read> methods are used. The other read methods
430automatically manage the read buffer. 1070automatically manage the read buffer.
431 1071
442Append the given callback to the end of the queue (C<push_read>) or 1082Append the given callback to the end of the queue (C<push_read>) or
443prepend it (C<unshift_read>). 1083prepend it (C<unshift_read>).
444 1084
445The callback is called each time some additional read data arrives. 1085The callback is called each time some additional read data arrives.
446 1086
447It must check wether enough data is in the read buffer already. 1087It must check whether enough data is in the read buffer already.
448 1088
449If not enough data is available, it must return the empty list or a false 1089If not enough data is available, it must return the empty list or a false
450value, in which case it will be called repeatedly until enough data is 1090value, in which case it will be called repeatedly until enough data is
451available (or an error condition is detected). 1091available (or an error condition is detected).
452 1092
454interested in (which can be none at all) and return a true value. After returning 1094interested in (which can be none at all) and return a true value. After returning
455true, it will be removed from the queue. 1095true, it will be removed from the queue.
456 1096
457=cut 1097=cut
458 1098
1099our %RH;
1100
1101sub register_read_type($$) {
1102 $RH{$_[0]} = $_[1];
1103}
1104
459sub push_read { 1105sub push_read {
460 my ($self, $cb) = @_; 1106 my $self = shift;
1107 my $cb = pop;
461 1108
1109 if (@_) {
1110 my $type = shift;
1111
1112 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
1113 ->($self, $cb, @_);
1114 }
1115
462 push @{ $self->{queue} }, $cb; 1116 push @{ $self->{_queue} }, $cb;
463 $self->_drain_rbuf; 1117 $self->_drain_rbuf;
464} 1118}
465 1119
466sub unshift_read { 1120sub unshift_read {
467 my ($self, $cb) = @_; 1121 my $self = shift;
1122 my $cb = pop;
468 1123
1124 if (@_) {
1125 my $type = shift;
1126
1127 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
1128 ->($self, $cb, @_);
1129 }
1130
1131
469 push @{ $self->{queue} }, $cb; 1132 unshift @{ $self->{_queue} }, $cb;
470 $self->_drain_rbuf; 1133 $self->_drain_rbuf;
471} 1134}
472 1135
473=item $handle->push_read_chunk ($len, $cb->($self, $data)) 1136=item $handle->push_read (type => @args, $cb)
474 1137
475=item $handle->unshift_read_chunk ($len, $cb->($self, $data)) 1138=item $handle->unshift_read (type => @args, $cb)
476 1139
477Append the given callback to the end of the queue (C<push_read_chunk>) or 1140Instead of providing a callback that parses the data itself you can chose
478prepend it (C<unshift_read_chunk>). 1141between a number of predefined parsing formats, for chunks of data, lines
1142etc.
479 1143
480The callback will be called only once C<$len> bytes have been read, and 1144Predefined types are (if you have ideas for additional types, feel free to
481these C<$len> bytes will be passed to the callback. 1145drop by and tell us):
482 1146
483=cut 1147=over 4
484 1148
485sub _read_chunk($$) { 1149=item chunk => $octets, $cb->($handle, $data)
1150
1151Invoke the callback only once C<$octets> bytes have been read. Pass the
1152data read to the callback. The callback will never be called with less
1153data.
1154
1155Example: read 2 bytes.
1156
1157 $handle->push_read (chunk => 2, sub {
1158 warn "yay ", unpack "H*", $_[1];
1159 });
1160
1161=cut
1162
1163register_read_type chunk => sub {
486 my ($self, $len, $cb) = @_; 1164 my ($self, $cb, $len) = @_;
487 1165
488 sub { 1166 sub {
489 $len <= length $_[0]{rbuf} or return; 1167 $len <= length $_[0]{rbuf} or return;
490 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 1168 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
491 1 1169 1
492 } 1170 }
493} 1171};
494 1172
495sub push_read_chunk { 1173=item line => [$eol, ]$cb->($handle, $line, $eol)
496 $_[0]->push_read (&_read_chunk);
497}
498
499
500sub unshift_read_chunk {
501 $_[0]->unshift_read (&_read_chunk);
502}
503
504=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
505
506=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
507
508Append the given callback to the end of the queue (C<push_read_line>) or
509prepend it (C<unshift_read_line>).
510 1174
511The callback will be called only once a full line (including the end of 1175The callback will be called only once a full line (including the end of
512line marker, C<$eol>) has been read. This line (excluding the end of line 1176line marker, C<$eol>) has been read. This line (excluding the end of line
513marker) will be passed to the callback as second argument (C<$line>), and 1177marker) will be passed to the callback as second argument (C<$line>), and
514the end of line marker as the third argument (C<$eol>). 1178the end of line marker as the third argument (C<$eol>).
525Partial lines at the end of the stream will never be returned, as they are 1189Partial lines at the end of the stream will never be returned, as they are
526not marked by the end of line marker. 1190not marked by the end of line marker.
527 1191
528=cut 1192=cut
529 1193
530sub _read_line($$) { 1194register_read_type line => sub {
531 my $self = shift; 1195 my ($self, $cb, $eol) = @_;
532 my $cb = pop;
533 my $eol = @_ ? shift : qr|(\015?\012)|;
534 my $pos;
535 1196
1197 if (@_ < 3) {
1198 # this is more than twice as fast as the generic code below
1199 sub {
1200 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1201
1202 $cb->($_[0], $1, $2);
1203 1
1204 }
1205 } else {
536 $eol = qr|(\Q$eol\E)| unless ref $eol; 1206 $eol = quotemeta $eol unless ref $eol;
537 $eol = qr|^(.*?)($eol)|; 1207 $eol = qr|^(.*?)($eol)|s;
1208
1209 sub {
1210 $_[0]{rbuf} =~ s/$eol// or return;
1211
1212 $cb->($_[0], $1, $2);
1213 1
1214 }
1215 }
1216};
1217
1218=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
1219
1220Makes a regex match against the regex object C<$accept> and returns
1221everything up to and including the match.
1222
1223Example: read a single line terminated by '\n'.
1224
1225 $handle->push_read (regex => qr<\n>, sub { ... });
1226
1227If C<$reject> is given and not undef, then it determines when the data is
1228to be rejected: it is matched against the data when the C<$accept> regex
1229does not match and generates an C<EBADMSG> error when it matches. This is
1230useful to quickly reject wrong data (to avoid waiting for a timeout or a
1231receive buffer overflow).
1232
1233Example: expect a single decimal number followed by whitespace, reject
1234anything else (not the use of an anchor).
1235
1236 $handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
1237
1238If C<$skip> is given and not C<undef>, then it will be matched against
1239the receive buffer when neither C<$accept> nor C<$reject> match,
1240and everything preceding and including the match will be accepted
1241unconditionally. This is useful to skip large amounts of data that you
1242know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1243have to start matching from the beginning. This is purely an optimisation
1244and is usually worth only when you expect more than a few kilobytes.
1245
1246Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1247expect the header to be very large (it isn't in practise, but...), we use
1248a skip regex to skip initial portions. The skip regex is tricky in that
1249it only accepts something not ending in either \015 or \012, as these are
1250required for the accept regex.
1251
1252 $handle->push_read (regex =>
1253 qr<\015\012\015\012>,
1254 undef, # no reject
1255 qr<^.*[^\015\012]>,
1256 sub { ... });
1257
1258=cut
1259
1260register_read_type regex => sub {
1261 my ($self, $cb, $accept, $reject, $skip) = @_;
1262
1263 my $data;
1264 my $rbuf = \$self->{rbuf};
538 1265
539 sub { 1266 sub {
540 $_[0]{rbuf} =~ s/$eol// or return; 1267 # accept
1268 if ($$rbuf =~ $accept) {
1269 $data .= substr $$rbuf, 0, $+[0], "";
1270 $cb->($self, $data);
1271 return 1;
1272 }
1273
1274 # reject
1275 if ($reject && $$rbuf =~ $reject) {
1276 $self->_error (Errno::EBADMSG);
1277 }
541 1278
542 $cb->($_[0], $1, $2); 1279 # skip
1280 if ($skip && $$rbuf =~ $skip) {
1281 $data .= substr $$rbuf, 0, $+[0], "";
1282 }
1283
1284 ()
1285 }
1286};
1287
1288=item netstring => $cb->($handle, $string)
1289
1290A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1291
1292Throws an error with C<$!> set to EBADMSG on format violations.
1293
1294=cut
1295
1296register_read_type netstring => sub {
1297 my ($self, $cb) = @_;
1298
1299 sub {
1300 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1301 if ($_[0]{rbuf} =~ /[^0-9]/) {
1302 $self->_error (Errno::EBADMSG);
1303 }
1304 return;
1305 }
1306
1307 my $len = $1;
1308
1309 $self->unshift_read (chunk => $len, sub {
1310 my $string = $_[1];
1311 $_[0]->unshift_read (chunk => 1, sub {
1312 if ($_[1] eq ",") {
1313 $cb->($_[0], $string);
1314 } else {
1315 $self->_error (Errno::EBADMSG);
1316 }
1317 });
1318 });
1319
543 1 1320 1
544 } 1321 }
545} 1322};
546 1323
547sub push_read_line { 1324=item packstring => $format, $cb->($handle, $string)
548 $_[0]->push_read (&_read_line);
549}
550 1325
551sub unshift_read_line { 1326An octet string prefixed with an encoded length. The encoding C<$format>
552 $_[0]->unshift_read (&_read_line); 1327uses the same format as a Perl C<pack> format, but must specify a single
553} 1328integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1329optional C<!>, C<< < >> or C<< > >> modifier).
1330
1331For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1332EPP uses a prefix of C<N> (4 octtes).
1333
1334Example: read a block of data prefixed by its length in BER-encoded
1335format (very efficient).
1336
1337 $handle->push_read (packstring => "w", sub {
1338 my ($handle, $data) = @_;
1339 });
1340
1341=cut
1342
1343register_read_type packstring => sub {
1344 my ($self, $cb, $format) = @_;
1345
1346 sub {
1347 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1348 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1349 or return;
1350
1351 $format = length pack $format, $len;
1352
1353 # bypass unshift if we already have the remaining chunk
1354 if ($format + $len <= length $_[0]{rbuf}) {
1355 my $data = substr $_[0]{rbuf}, $format, $len;
1356 substr $_[0]{rbuf}, 0, $format + $len, "";
1357 $cb->($_[0], $data);
1358 } else {
1359 # remove prefix
1360 substr $_[0]{rbuf}, 0, $format, "";
1361
1362 # read remaining chunk
1363 $_[0]->unshift_read (chunk => $len, $cb);
1364 }
1365
1366 1
1367 }
1368};
1369
1370=item json => $cb->($handle, $hash_or_arrayref)
1371
1372Reads a JSON object or array, decodes it and passes it to the
1373callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1374
1375If a C<json> object was passed to the constructor, then that will be used
1376for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1377
1378This read type uses the incremental parser available with JSON version
13792.09 (and JSON::XS version 2.2) and above. You have to provide a
1380dependency on your own: this module will load the JSON module, but
1381AnyEvent does not depend on it itself.
1382
1383Since JSON texts are fully self-delimiting, the C<json> read and write
1384types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1385the C<json> write type description, above, for an actual example.
1386
1387=cut
1388
1389register_read_type json => sub {
1390 my ($self, $cb) = @_;
1391
1392 my $json = $self->{json} ||=
1393 eval { require JSON::XS; JSON::XS->new->utf8 }
1394 || do { require JSON; JSON->new->utf8 };
1395
1396 my $data;
1397 my $rbuf = \$self->{rbuf};
1398
1399 sub {
1400 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1401
1402 if ($ref) {
1403 $self->{rbuf} = $json->incr_text;
1404 $json->incr_text = "";
1405 $cb->($self, $ref);
1406
1407 1
1408 } elsif ($@) {
1409 # error case
1410 $json->incr_skip;
1411
1412 $self->{rbuf} = $json->incr_text;
1413 $json->incr_text = "";
1414
1415 $self->_error (Errno::EBADMSG);
1416
1417 ()
1418 } else {
1419 $self->{rbuf} = "";
1420
1421 ()
1422 }
1423 }
1424};
1425
1426=item storable => $cb->($handle, $ref)
1427
1428Deserialises a L<Storable> frozen representation as written by the
1429C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1430data).
1431
1432Raises C<EBADMSG> error if the data could not be decoded.
1433
1434=cut
1435
1436register_read_type storable => sub {
1437 my ($self, $cb) = @_;
1438
1439 require Storable;
1440
1441 sub {
1442 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1443 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1444 or return;
1445
1446 my $format = length pack "w", $len;
1447
1448 # bypass unshift if we already have the remaining chunk
1449 if ($format + $len <= length $_[0]{rbuf}) {
1450 my $data = substr $_[0]{rbuf}, $format, $len;
1451 substr $_[0]{rbuf}, 0, $format + $len, "";
1452 $cb->($_[0], Storable::thaw ($data));
1453 } else {
1454 # remove prefix
1455 substr $_[0]{rbuf}, 0, $format, "";
1456
1457 # read remaining chunk
1458 $_[0]->unshift_read (chunk => $len, sub {
1459 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1460 $cb->($_[0], $ref);
1461 } else {
1462 $self->_error (Errno::EBADMSG);
1463 }
1464 });
1465 }
1466
1467 1
1468 }
1469};
1470
1471=back
1472
1473=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
1474
1475This function (not method) lets you add your own types to C<push_read>.
1476
1477Whenever the given C<type> is used, C<push_read> will invoke the code
1478reference with the handle object, the callback and the remaining
1479arguments.
1480
1481The code reference is supposed to return a callback (usually a closure)
1482that works as a plain read callback (see C<< ->push_read ($cb) >>).
1483
1484It should invoke the passed callback when it is done reading (remember to
1485pass C<$handle> as first argument as all other callbacks do that).
1486
1487Note that this is a function, and all types registered this way will be
1488global, so try to use unique names.
1489
1490For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
1491search for C<register_read_type>)).
554 1492
555=item $handle->stop_read 1493=item $handle->stop_read
556 1494
557=item $handle->start_read 1495=item $handle->start_read
558 1496
559In rare cases you actually do not want to read anything form the 1497In rare cases you actually do not want to read anything from the
560socket. In this case you can call C<stop_read>. Neither C<on_read> no 1498socket. In this case you can call C<stop_read>. Neither C<on_read> nor
561any queued callbacks will be executed then. To start readign again, call 1499any queued callbacks will be executed then. To start reading again, call
562C<start_read>. 1500C<start_read>.
1501
1502Note that AnyEvent::Handle will automatically C<start_read> for you when
1503you change the C<on_read> callback or push/unshift a read callback, and it
1504will automatically C<stop_read> for you when neither C<on_read> is set nor
1505there are any read requests in the queue.
1506
1507These methods will have no effect when in TLS mode (as TLS doesn't support
1508half-duplex connections).
563 1509
564=cut 1510=cut
565 1511
566sub stop_read { 1512sub stop_read {
567 my ($self) = @_; 1513 my ($self) = @_;
568 1514
569 delete $self->{rw}; 1515 delete $self->{_rw} unless $self->{tls};
570} 1516}
571 1517
572sub start_read { 1518sub start_read {
573 my ($self) = @_; 1519 my ($self) = @_;
574 1520
575 unless ($self->{rw} || $self->{eof}) { 1521 unless ($self->{_rw} || $self->{_eof}) {
576 Scalar::Util::weaken $self; 1522 Scalar::Util::weaken $self;
577 1523
578 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1524 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1525 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
579 my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} || 8192, length $self->{rbuf}; 1526 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
580 1527
581 if ($len > 0) { 1528 if ($len > 0) {
582 if (defined $self->{rbuf_max}) { 1529 $self->{_activity} = AnyEvent->now;
583 if ($self->{rbuf_max} < length $self->{rbuf}) { 1530
584 $! = &Errno::ENOSPC; return $self->error; 1531 if ($self->{tls}) {
585 } 1532 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1533
1534 &_dotls ($self);
1535 } else {
1536 $self->_drain_rbuf;
586 } 1537 }
587 1538
588 } elsif (defined $len) { 1539 } elsif (defined $len) {
589 $self->{eof} = 1;
590 delete $self->{rw}; 1540 delete $self->{_rw};
1541 $self->{_eof} = 1;
1542 $self->_drain_rbuf;
591 1543
592 } elsif ($! != EAGAIN && $! != EINTR) { 1544 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
593 return $self->error; 1545 return $self->_error ($!, 1);
594 } 1546 }
595
596 $self->_drain_rbuf;
597 }); 1547 });
598 } 1548 }
599} 1549}
600 1550
1551our $ERROR_SYSCALL;
1552our $ERROR_WANT_READ;
1553
1554sub _tls_error {
1555 my ($self, $err) = @_;
1556
1557 return $self->_error ($!, 1)
1558 if $err == Net::SSLeay::ERROR_SYSCALL ();
1559
1560 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1561
1562 # reduce error string to look less scary
1563 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1564
1565 if ($self->{_on_starttls}) {
1566 (delete $self->{_on_starttls})->($self, undef, $err);
1567 &_freetls;
1568 } else {
1569 &_freetls;
1570 $self->_error (Errno::EPROTO, 1, $err);
1571 }
1572}
1573
1574# poll the write BIO and send the data if applicable
1575# also decode read data if possible
1576# this is basiclaly our TLS state machine
1577# more efficient implementations are possible with openssl,
1578# but not with the buggy and incomplete Net::SSLeay.
1579sub _dotls {
1580 my ($self) = @_;
1581
1582 my $tmp;
1583
1584 if (length $self->{_tls_wbuf}) {
1585 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1586 substr $self->{_tls_wbuf}, 0, $tmp, "";
1587 }
1588
1589 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1590 return $self->_tls_error ($tmp)
1591 if $tmp != $ERROR_WANT_READ
1592 && ($tmp != $ERROR_SYSCALL || $!);
1593 }
1594
1595 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1596 unless (length $tmp) {
1597 $self->{_on_starttls}
1598 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1599 &_freetls;
1600
1601 if ($self->{on_stoptls}) {
1602 $self->{on_stoptls}($self);
1603 return;
1604 } else {
1605 # let's treat SSL-eof as we treat normal EOF
1606 delete $self->{_rw};
1607 $self->{_eof} = 1;
1608 }
1609 }
1610
1611 $self->{_tls_rbuf} .= $tmp;
1612 $self->_drain_rbuf;
1613 $self->{tls} or return; # tls session might have gone away in callback
1614 }
1615
1616 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1617 return $self->_tls_error ($tmp)
1618 if $tmp != $ERROR_WANT_READ
1619 && ($tmp != $ERROR_SYSCALL || $!);
1620
1621 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1622 $self->{wbuf} .= $tmp;
1623 $self->_drain_wbuf;
1624 }
1625
1626 $self->{_on_starttls}
1627 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1628 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1629}
1630
1631=item $handle->starttls ($tls[, $tls_ctx])
1632
1633Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1634object is created, you can also do that at a later time by calling
1635C<starttls>.
1636
1637Starting TLS is currently an asynchronous operation - when you push some
1638write data and then call C<< ->starttls >> then TLS negotiation will start
1639immediately, after which the queued write data is then sent.
1640
1641The first argument is the same as the C<tls> constructor argument (either
1642C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1643
1644The second argument is the optional C<AnyEvent::TLS> object that is used
1645when AnyEvent::Handle has to create its own TLS connection object, or
1646a hash reference with C<< key => value >> pairs that will be used to
1647construct a new context.
1648
1649The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1650context in C<< $handle->{tls_ctx} >> after this call and can be used or
1651changed to your liking. Note that the handshake might have already started
1652when this function returns.
1653
1654If it an error to start a TLS handshake more than once per
1655AnyEvent::Handle object (this is due to bugs in OpenSSL).
1656
1657=cut
1658
1659our %TLS_CACHE; #TODO not yet documented, should we?
1660
1661sub starttls {
1662 my ($self, $ssl, $ctx) = @_;
1663
1664 require Net::SSLeay;
1665
1666 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1667 if $self->{tls};
1668
1669 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1670 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1671
1672 $ctx ||= $self->{tls_ctx};
1673
1674 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1675
1676 if ("HASH" eq ref $ctx) {
1677 require AnyEvent::TLS;
1678
1679 if ($ctx->{cache}) {
1680 my $key = $ctx+0;
1681 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1682 } else {
1683 $ctx = new AnyEvent::TLS %$ctx;
1684 }
1685 }
1686
1687 $self->{tls_ctx} = $ctx || TLS_CTX ();
1688 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});
1689
1690 # basically, this is deep magic (because SSL_read should have the same issues)
1691 # but the openssl maintainers basically said: "trust us, it just works".
1692 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1693 # and mismaintained ssleay-module doesn't even offer them).
1694 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1695 #
1696 # in short: this is a mess.
1697 #
1698 # note that we do not try to keep the length constant between writes as we are required to do.
1699 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1700 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1701 # have identity issues in that area.
1702# Net::SSLeay::CTX_set_mode ($ssl,
1703# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1704# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1705 Net::SSLeay::CTX_set_mode ($ssl, 1|2);
1706
1707 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1708 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1709
1710 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1711
1712 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1713 if $self->{on_starttls};
1714
1715 &_dotls; # need to trigger the initial handshake
1716 $self->start_read; # make sure we actually do read
1717}
1718
1719=item $handle->stoptls
1720
1721Shuts down the SSL connection - this makes a proper EOF handshake by
1722sending a close notify to the other side, but since OpenSSL doesn't
1723support non-blocking shut downs, it is not possible to re-use the stream
1724afterwards.
1725
1726=cut
1727
1728sub stoptls {
1729 my ($self) = @_;
1730
1731 if ($self->{tls}) {
1732 Net::SSLeay::shutdown ($self->{tls});
1733
1734 &_dotls;
1735
1736# # we don't give a shit. no, we do, but we can't. no...#d#
1737# # we, we... have to use openssl :/#d#
1738# &_freetls;#d#
1739 }
1740}
1741
1742sub _freetls {
1743 my ($self) = @_;
1744
1745 return unless $self->{tls};
1746
1747 $self->{tls_ctx}->_put_session (delete $self->{tls});
1748
1749 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1750}
1751
1752sub DESTROY {
1753 my ($self) = @_;
1754
1755 &_freetls;
1756
1757 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1758
1759 if ($linger && length $self->{wbuf} && $self->{fh}) {
1760 my $fh = delete $self->{fh};
1761 my $wbuf = delete $self->{wbuf};
1762
1763 my @linger;
1764
1765 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1766 my $len = syswrite $fh, $wbuf, length $wbuf;
1767
1768 if ($len > 0) {
1769 substr $wbuf, 0, $len, "";
1770 } else {
1771 @linger = (); # end
1772 }
1773 });
1774 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1775 @linger = ();
1776 });
1777 }
1778}
1779
1780=item $handle->destroy
1781
1782Shuts down the handle object as much as possible - this call ensures that
1783no further callbacks will be invoked and as many resources as possible
1784will be freed. You must not call any methods on the object afterwards.
1785
1786Normally, you can just "forget" any references to an AnyEvent::Handle
1787object and it will simply shut down. This works in fatal error and EOF
1788callbacks, as well as code outside. It does I<NOT> work in a read or write
1789callback, so when you want to destroy the AnyEvent::Handle object from
1790within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1791that case.
1792
1793Destroying the handle object in this way has the advantage that callbacks
1794will be removed as well, so if those are the only reference holders (as
1795is common), then one doesn't need to do anything special to break any
1796reference cycles.
1797
1798The handle might still linger in the background and write out remaining
1799data, as specified by the C<linger> option, however.
1800
1801=cut
1802
1803sub destroy {
1804 my ($self) = @_;
1805
1806 $self->DESTROY;
1807 %$self = ();
1808}
1809
1810=item AnyEvent::Handle::TLS_CTX
1811
1812This function creates and returns the AnyEvent::TLS object used by default
1813for TLS mode.
1814
1815The context is created by calling L<AnyEvent::TLS> without any arguments.
1816
1817=cut
1818
1819our $TLS_CTX;
1820
1821sub TLS_CTX() {
1822 $TLS_CTX ||= do {
1823 require AnyEvent::TLS;
1824
1825 new AnyEvent::TLS
1826 }
1827}
1828
601=back 1829=back
602 1830
1831
1832=head1 NONFREQUENTLY ASKED QUESTIONS
1833
1834=over 4
1835
1836=item I C<undef> the AnyEvent::Handle reference inside my callback and
1837still get further invocations!
1838
1839That's because AnyEvent::Handle keeps a reference to itself when handling
1840read or write callbacks.
1841
1842It is only safe to "forget" the reference inside EOF or error callbacks,
1843from within all other callbacks, you need to explicitly call the C<<
1844->destroy >> method.
1845
1846=item I get different callback invocations in TLS mode/Why can't I pause
1847reading?
1848
1849Unlike, say, TCP, TLS connections do not consist of two independent
1850communication channels, one for each direction. Or put differently. The
1851read and write directions are not independent of each other: you cannot
1852write data unless you are also prepared to read, and vice versa.
1853
1854This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1855callback invocations when you are not expecting any read data - the reason
1856is that AnyEvent::Handle always reads in TLS mode.
1857
1858During the connection, you have to make sure that you always have a
1859non-empty read-queue, or an C<on_read> watcher. At the end of the
1860connection (or when you no longer want to use it) you can call the
1861C<destroy> method.
1862
1863=item How do I read data until the other side closes the connection?
1864
1865If you just want to read your data into a perl scalar, the easiest way
1866to achieve this is by setting an C<on_read> callback that does nothing,
1867clearing the C<on_eof> callback and in the C<on_error> callback, the data
1868will be in C<$_[0]{rbuf}>:
1869
1870 $handle->on_read (sub { });
1871 $handle->on_eof (undef);
1872 $handle->on_error (sub {
1873 my $data = delete $_[0]{rbuf};
1874 });
1875
1876The reason to use C<on_error> is that TCP connections, due to latencies
1877and packets loss, might get closed quite violently with an error, when in
1878fact, all data has been received.
1879
1880It is usually better to use acknowledgements when transferring data,
1881to make sure the other side hasn't just died and you got the data
1882intact. This is also one reason why so many internet protocols have an
1883explicit QUIT command.
1884
1885=item I don't want to destroy the handle too early - how do I wait until
1886all data has been written?
1887
1888After writing your last bits of data, set the C<on_drain> callback
1889and destroy the handle in there - with the default setting of
1890C<low_water_mark> this will be called precisely when all data has been
1891written to the socket:
1892
1893 $handle->push_write (...);
1894 $handle->on_drain (sub {
1895 warn "all data submitted to the kernel\n";
1896 undef $handle;
1897 });
1898
1899If you just want to queue some data and then signal EOF to the other side,
1900consider using C<< ->push_shutdown >> instead.
1901
1902=item I want to contact a TLS/SSL server, I don't care about security.
1903
1904If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1905simply connect to it and then create the AnyEvent::Handle with the C<tls>
1906parameter:
1907
1908 tcp_connect $host, $port, sub {
1909 my ($fh) = @_;
1910
1911 my $handle = new AnyEvent::Handle
1912 fh => $fh,
1913 tls => "connect",
1914 on_error => sub { ... };
1915
1916 $handle->push_write (...);
1917 };
1918
1919=item I want to contact a TLS/SSL server, I do care about security.
1920
1921Then you should additionally enable certificate verification, including
1922peername verification, if the protocol you use supports it (see
1923L<AnyEvent::TLS>, C<verify_peername>).
1924
1925E.g. for HTTPS:
1926
1927 tcp_connect $host, $port, sub {
1928 my ($fh) = @_;
1929
1930 my $handle = new AnyEvent::Handle
1931 fh => $fh,
1932 peername => $host,
1933 tls => "connect",
1934 tls_ctx => { verify => 1, verify_peername => "https" },
1935 ...
1936
1937Note that you must specify the hostname you connected to (or whatever
1938"peername" the protocol needs) as the C<peername> argument, otherwise no
1939peername verification will be done.
1940
1941The above will use the system-dependent default set of trusted CA
1942certificates. If you want to check against a specific CA, add the
1943C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
1944
1945 tls_ctx => {
1946 verify => 1,
1947 verify_peername => "https",
1948 ca_file => "my-ca-cert.pem",
1949 },
1950
1951=item I want to create a TLS/SSL server, how do I do that?
1952
1953Well, you first need to get a server certificate and key. You have
1954three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
1955self-signed certificate (cheap. check the search engine of your choice,
1956there are many tutorials on the net) or c) make your own CA (tinyca2 is a
1957nice program for that purpose).
1958
1959Then create a file with your private key (in PEM format, see
1960L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
1961file should then look like this:
1962
1963 -----BEGIN RSA PRIVATE KEY-----
1964 ...header data
1965 ... lots of base64'y-stuff
1966 -----END RSA PRIVATE KEY-----
1967
1968 -----BEGIN CERTIFICATE-----
1969 ... lots of base64'y-stuff
1970 -----END CERTIFICATE-----
1971
1972The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
1973specify this file as C<cert_file>:
1974
1975 tcp_server undef, $port, sub {
1976 my ($fh) = @_;
1977
1978 my $handle = new AnyEvent::Handle
1979 fh => $fh,
1980 tls => "accept",
1981 tls_ctx => { cert_file => "my-server-keycert.pem" },
1982 ...
1983
1984When you have intermediate CA certificates that your clients might not
1985know about, just append them to the C<cert_file>.
1986
1987=back
1988
1989
1990=head1 SUBCLASSING AnyEvent::Handle
1991
1992In many cases, you might want to subclass AnyEvent::Handle.
1993
1994To make this easier, a given version of AnyEvent::Handle uses these
1995conventions:
1996
1997=over 4
1998
1999=item * all constructor arguments become object members.
2000
2001At least initially, when you pass a C<tls>-argument to the constructor it
2002will end up in C<< $handle->{tls} >>. Those members might be changed or
2003mutated later on (for example C<tls> will hold the TLS connection object).
2004
2005=item * other object member names are prefixed with an C<_>.
2006
2007All object members not explicitly documented (internal use) are prefixed
2008with an underscore character, so the remaining non-C<_>-namespace is free
2009for use for subclasses.
2010
2011=item * all members not documented here and not prefixed with an underscore
2012are free to use in subclasses.
2013
2014Of course, new versions of AnyEvent::Handle may introduce more "public"
2015member variables, but thats just life, at least it is documented.
2016
2017=back
2018
603=head1 AUTHOR 2019=head1 AUTHOR
604 2020
605Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2021Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
606 2022
607=cut 2023=cut

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