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Revision 1.38 by root, Mon May 26 21:28:33 2008 UTC vs.
Revision 1.149 by root, Thu Jul 16 03:48:33 2009 UTC

1package AnyEvent::Handle; 1package AnyEvent::Handle;
2 2
3no warnings; 3no warnings;
4use strict; 4use strict qw(subs vars);
5 5
6use AnyEvent (); 6use AnyEvent ();
7use AnyEvent::Util qw(WSAWOULDBLOCK); 7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util (); 8use Scalar::Util ();
9use Carp (); 9use Carp ();
10use Fcntl (); 10use Fcntl ();
11use Errno qw/EAGAIN EINTR/; 11use Errno qw(EAGAIN EINTR);
12 12
13=head1 NAME 13=head1 NAME
14 14
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 16
17=cut 17=cut
18 18
19our $VERSION = '0.04'; 19our $VERSION = 4.82;
20 20
21=head1 SYNOPSIS 21=head1 SYNOPSIS
22 22
23 use AnyEvent; 23 use AnyEvent;
24 use AnyEvent::Handle; 24 use AnyEvent::Handle;
25 25
26 my $cv = AnyEvent->condvar; 26 my $cv = AnyEvent->condvar;
27 27
28 my $handle = 28 my $hdl; $hdl = new AnyEvent::Handle
29 AnyEvent::Handle->new (
30 fh => \*STDIN, 29 fh => \*STDIN,
31 on_eof => sub { 30 on_error => sub {
32 $cv->broadcast; 31 warn "got error $_[2]\n";
33 }, 32 $cv->send;
34 ); 33 );
35 34
36 # send some request line 35 # send some request line
37 $handle->push_write ("getinfo\015\012"); 36 $hdl->push_write ("getinfo\015\012");
38 37
39 # read the response line 38 # read the response line
40 $handle->push_read (line => sub { 39 $hdl->push_read (line => sub {
41 my ($handle, $line) = @_; 40 my ($hdl, $line) = @_;
42 warn "read line <$line>\n"; 41 warn "got line <$line>\n";
43 $cv->send; 42 $cv->send;
44 }); 43 });
45 44
46 $cv->recv; 45 $cv->recv;
47 46
49 48
50This module is a helper module to make it easier to do event-based I/O on 49This module 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 50filehandles. For utility functions for doing non-blocking connects and accepts
52on sockets see L<AnyEvent::Util>. 51on sockets see L<AnyEvent::Util>.
53 52
53The L<AnyEvent::Intro> tutorial contains some well-documented
54AnyEvent::Handle examples.
55
54In the following, when the documentation refers to of "bytes" then this 56In the following, when the documentation refers to of "bytes" then this
55means characters. As sysread and syswrite are used for all I/O, their 57means characters. As sysread and syswrite are used for all I/O, their
56treatment of characters applies to this module as well. 58treatment of characters applies to this module as well.
57 59
58All callbacks will be invoked with the handle object as their first 60All callbacks will be invoked with the handle object as their first
60 62
61=head1 METHODS 63=head1 METHODS
62 64
63=over 4 65=over 4
64 66
65=item B<new (%args)> 67=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
66 68
67The constructor supports these arguments (all as key => value pairs). 69The constructor supports these arguments (all as C<< key => value >> pairs).
68 70
69=over 4 71=over 4
70 72
71=item fh => $filehandle [MANDATORY] 73=item fh => $filehandle [MANDATORY]
72 74
73The filehandle this L<AnyEvent::Handle> object will operate on. 75The filehandle this L<AnyEvent::Handle> object will operate on.
74 76
75NOTE: The filehandle will be set to non-blocking (using 77NOTE: The filehandle will be set to non-blocking mode (using
76AnyEvent::Util::fh_nonblocking). 78C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
79that mode.
77 80
78=item on_eof => $cb->($self) 81=item on_eof => $cb->($handle)
79 82
80Set the callback to be called on EOF. 83Set the callback to be called when an end-of-file condition is detected,
84i.e. in the case of a socket, when the other side has closed the
85connection cleanly.
81 86
87For sockets, this just means that the other side has stopped sending data,
88you can still try to write data, and, in fact, one can return from the EOF
89callback and continue writing data, as only the read part has been shut
90down.
91
82While not mandatory, it is highly recommended to set an eof callback, 92While not mandatory, it is I<highly> recommended to set an EOF callback,
83otherwise you might end up with a closed socket while you are still 93otherwise you might end up with a closed socket while you are still
84waiting for data. 94waiting for data.
85 95
86=item on_error => $cb->($self) 96If an EOF condition has been detected but no C<on_eof> callback has been
97set, then a fatal error will be raised with C<$!> set to <0>.
87 98
99=item on_error => $cb->($handle, $fatal, $message)
100
88This is the fatal error callback, that is called when, well, a fatal error 101This is the error callback, which is called when, well, some error
89occurs, such as not being able to resolve the hostname, failure to connect 102occured, such as not being able to resolve the hostname, failure to
90or a read error. 103connect or a read error.
91 104
92The object will not be in a usable state when this callback has been 105Some errors are fatal (which is indicated by C<$fatal> being true). On
93called. 106fatal errors the handle object will be destroyed (by a call to C<< ->
107destroy >>) after invoking the error callback (which means you are free to
108examine the handle object). Examples of fatal errors are an EOF condition
109with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors.
110
111AnyEvent::Handle tries to find an appropriate error code for you to check
112against, but in some cases (TLS errors), this does not work well. It is
113recommended to always output the C<$message> argument in human-readable
114error messages (it's usually the same as C<"$!">).
115
116Non-fatal errors can be retried by simply returning, but it is recommended
117to simply ignore this parameter and instead abondon the handle object
118when this callback is invoked. Examples of non-fatal errors are timeouts
119C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
94 120
95On callback entrance, the value of C<$!> contains the operating system 121On callback entrance, the value of C<$!> contains the operating system
96error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>). 122error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
97 123C<EPROTO>).
98The callback should throw an exception. If it returns, then
99AnyEvent::Handle will C<croak> for you.
100 124
101While not mandatory, it is I<highly> recommended to set this callback, as 125While not mandatory, it is I<highly> recommended to set this callback, as
102you will not be notified of errors otherwise. The default simply calls 126you will not be notified of errors otherwise. The default simply calls
103die. 127C<croak>.
104 128
105=item on_read => $cb->($self) 129=item on_read => $cb->($handle)
106 130
107This sets the default read callback, which is called when data arrives 131This sets the default read callback, which is called when data arrives
108and no read request is in the queue. 132and no read request is in the queue (unlike read queue callbacks, this
133callback will only be called when at least one octet of data is in the
134read buffer).
109 135
110To access (and remove data from) the read buffer, use the C<< ->rbuf >> 136To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111method or access the C<$self->{rbuf}> member directly. 137method or access the C<< $handle->{rbuf} >> member directly. Note that you
138must not enlarge or modify the read buffer, you can only remove data at
139the beginning from it.
112 140
113When an EOF condition is detected then AnyEvent::Handle will first try to 141When an EOF condition is detected then AnyEvent::Handle will first try to
114feed all the remaining data to the queued callbacks and C<on_read> before 142feed all the remaining data to the queued callbacks and C<on_read> before
115calling the C<on_eof> callback. If no progress can be made, then a fatal 143calling the C<on_eof> callback. If no progress can be made, then a fatal
116error will be raised (with C<$!> set to C<EPIPE>). 144error will be raised (with C<$!> set to C<EPIPE>).
117 145
118=item on_drain => $cb->() 146=item on_drain => $cb->($handle)
119 147
120This sets the callback that is called when the write buffer becomes empty 148This sets the callback that is called when the write buffer becomes empty
121(or when the callback is set and the buffer is empty already). 149(or when the callback is set and the buffer is empty already).
122 150
123To append to the write buffer, use the C<< ->push_write >> method. 151To append to the write buffer, use the C<< ->push_write >> method.
124 152
153This callback is useful when you don't want to put all of your write data
154into the queue at once, for example, when you want to write the contents
155of some file to the socket you might not want to read the whole file into
156memory and push it into the queue, but instead only read more data from
157the file when the write queue becomes empty.
158
159=item timeout => $fractional_seconds
160
161If non-zero, then this enables an "inactivity" timeout: whenever this many
162seconds pass without a successful read or write on the underlying file
163handle, the C<on_timeout> callback will be invoked (and if that one is
164missing, a non-fatal C<ETIMEDOUT> error will be raised).
165
166Note that timeout processing is also active when you currently do not have
167any outstanding read or write requests: If you plan to keep the connection
168idle then you should disable the timout temporarily or ignore the timeout
169in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
170restart the timeout.
171
172Zero (the default) disables this timeout.
173
174=item on_timeout => $cb->($handle)
175
176Called whenever the inactivity timeout passes. If you return from this
177callback, then the timeout will be reset as if some activity had happened,
178so this condition is not fatal in any way.
179
125=item rbuf_max => <bytes> 180=item rbuf_max => <bytes>
126 181
127If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 182If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128when the read buffer ever (strictly) exceeds this size. This is useful to 183when the read buffer ever (strictly) exceeds this size. This is useful to
129avoid denial-of-service attacks. 184avoid some forms of denial-of-service attacks.
130 185
131For example, a server accepting connections from untrusted sources should 186For example, a server accepting connections from untrusted sources should
132be configured to accept only so-and-so much data that it cannot act on 187be configured to accept only so-and-so much data that it cannot act on
133(for example, when expecting a line, an attacker could send an unlimited 188(for example, when expecting a line, an attacker could send an unlimited
134amount of data without a callback ever being called as long as the line 189amount of data without a callback ever being called as long as the line
135isn't finished). 190isn't finished).
136 191
192=item autocork => <boolean>
193
194When disabled (the default), then C<push_write> will try to immediately
195write the data to the handle, if possible. This avoids having to register
196a write watcher and wait for the next event loop iteration, but can
197be inefficient if you write multiple small chunks (on the wire, this
198disadvantage is usually avoided by your kernel's nagle algorithm, see
199C<no_delay>, but this option can save costly syscalls).
200
201When enabled, then writes will always be queued till the next event loop
202iteration. This is efficient when you do many small writes per iteration,
203but less efficient when you do a single write only per iteration (or when
204the write buffer often is full). It also increases write latency.
205
206=item no_delay => <boolean>
207
208When doing small writes on sockets, your operating system kernel might
209wait a bit for more data before actually sending it out. This is called
210the Nagle algorithm, and usually it is beneficial.
211
212In some situations you want as low a delay as possible, which can be
213accomplishd by setting this option to a true value.
214
215The default is your opertaing system's default behaviour (most likely
216enabled), this option explicitly enables or disables it, if possible.
217
137=item read_size => <bytes> 218=item read_size => <bytes>
138 219
139The default read block size (the amount of bytes this module will try to read 220The default read block size (the amount of bytes this module will
140on each [loop iteration). Default: C<4096>. 221try to read during each loop iteration, which affects memory
222requirements). Default: C<8192>.
141 223
142=item low_water_mark => <bytes> 224=item low_water_mark => <bytes>
143 225
144Sets the amount of bytes (default: C<0>) that make up an "empty" write 226Sets the amount of bytes (default: C<0>) that make up an "empty" write
145buffer: If the write reaches this size or gets even samller it is 227buffer: If the write reaches this size or gets even samller it is
146considered empty. 228considered empty.
147 229
230Sometimes it can be beneficial (for performance reasons) to add data to
231the write buffer before it is fully drained, but this is a rare case, as
232the operating system kernel usually buffers data as well, so the default
233is good in almost all cases.
234
235=item linger => <seconds>
236
237If non-zero (default: C<3600>), then the destructor of the
238AnyEvent::Handle object will check whether there is still outstanding
239write data and will install a watcher that will write this data to the
240socket. No errors will be reported (this mostly matches how the operating
241system treats outstanding data at socket close time).
242
243This will not work for partial TLS data that could not be encoded
244yet. This data will be lost. Calling the C<stoptls> method in time might
245help.
246
247=item peername => $string
248
249A string used to identify the remote site - usually the DNS hostname
250(I<not> IDN!) used to create the connection, rarely the IP address.
251
252Apart from being useful in error messages, this string is also used in TLS
253peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
254verification will be skipped when C<peername> is not specified or
255C<undef>.
256
148=item tls => "accept" | "connect" | Net::SSLeay::SSL object 257=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149 258
150When this parameter is given, it enables TLS (SSL) mode, that means it 259When this parameter is given, it enables TLS (SSL) mode, that means
151will start making tls handshake and will transparently encrypt/decrypt 260AnyEvent will start a TLS handshake as soon as the conenction has been
152data. 261established and will transparently encrypt/decrypt data afterwards.
262
263All TLS protocol errors will be signalled as C<EPROTO>, with an
264appropriate error message.
153 265
154TLS mode requires Net::SSLeay to be installed (it will be loaded 266TLS mode requires Net::SSLeay to be installed (it will be loaded
155automatically when you try to create a TLS handle). 267automatically when you try to create a TLS handle): this module doesn't
268have a dependency on that module, so if your module requires it, you have
269to add the dependency yourself.
156 270
157For the TLS server side, use C<accept>, and for the TLS client side of a 271Unlike TCP, TLS has a server and client side: for the TLS server side, use
158connection, use C<connect> mode. 272C<accept>, and for the TLS client side of a connection, use C<connect>
273mode.
159 274
160You can also provide your own TLS connection object, but you have 275You can also provide your own TLS connection object, but you have
161to make sure that you call either C<Net::SSLeay::set_connect_state> 276to make sure that you call either C<Net::SSLeay::set_connect_state>
162or C<Net::SSLeay::set_accept_state> on it before you pass it to 277or C<Net::SSLeay::set_accept_state> on it before you pass it to
163AnyEvent::Handle. 278AnyEvent::Handle. Also, this module will take ownership of this connection
279object.
164 280
281At some future point, AnyEvent::Handle might switch to another TLS
282implementation, then the option to use your own session object will go
283away.
284
285B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
286passing in the wrong integer will lead to certain crash. This most often
287happens when one uses a stylish C<< tls => 1 >> and is surprised about the
288segmentation fault.
289
165See the C<starttls> method if you need to start TLs negotiation later. 290See the C<< ->starttls >> method for when need to start TLS negotiation later.
166 291
167=item tls_ctx => $ssl_ctx 292=item tls_ctx => $anyevent_tls
168 293
169Use the given Net::SSLeay::CTX object to create the new TLS connection 294Use the given C<AnyEvent::TLS> object to create the new TLS connection
170(unless a connection object was specified directly). If this parameter is 295(unless a connection object was specified directly). If this parameter is
171missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 296missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172 297
173=item filter_r => $cb 298Instead of an object, you can also specify a hash reference with C<< key
299=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
300new TLS context object.
174 301
175=item filter_w => $cb 302=item on_starttls => $cb->($handle, $success[, $error_message])
176 303
177These exist, but are undocumented at this time. 304This callback will be invoked when the TLS/SSL handshake has finished. If
305C<$success> is true, then the TLS handshake succeeded, otherwise it failed
306(C<on_stoptls> will not be called in this case).
307
308The session in C<< $handle->{tls} >> can still be examined in this
309callback, even when the handshake was not successful.
310
311TLS handshake failures will not cause C<on_error> to be invoked when this
312callback is in effect, instead, the error message will be passed to C<on_starttls>.
313
314Without this callback, handshake failures lead to C<on_error> being
315called, as normal.
316
317Note that you cannot call C<starttls> right again in this callback. If you
318need to do that, start an zero-second timer instead whose callback can
319then call C<< ->starttls >> again.
320
321=item on_stoptls => $cb->($handle)
322
323When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
324set, then it will be invoked after freeing the TLS session. If it is not,
325then a TLS shutdown condition will be treated like a normal EOF condition
326on the handle.
327
328The session in C<< $handle->{tls} >> can still be examined in this
329callback.
330
331This callback will only be called on TLS shutdowns, not when the
332underlying handle signals EOF.
333
334=item json => JSON or JSON::XS object
335
336This is the json coder object used by the C<json> read and write types.
337
338If you don't supply it, then AnyEvent::Handle will create and use a
339suitable one (on demand), which will write and expect UTF-8 encoded JSON
340texts.
341
342Note that you are responsible to depend on the JSON module if you want to
343use this functionality, as AnyEvent does not have a dependency itself.
178 344
179=back 345=back
180 346
181=cut 347=cut
182 348
183sub new { 349sub new {
184 my $class = shift; 350 my $class = shift;
185
186 my $self = bless { @_ }, $class; 351 my $self = bless { @_ }, $class;
187 352
188 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 353 $self->{fh} or Carp::croak "mandatory argument fh is missing";
189 354
190 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 355 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
191 356
192 if ($self->{tls}) { 357 $self->{_activity} = AnyEvent->now;
193 require Net::SSLeay; 358 $self->_timeout;
359
360 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
361
194 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 362 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
195 } 363 if $self->{tls};
196 364
197 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
198 $self->on_error (delete $self->{on_error}) if $self->{on_error};
199 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 365 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
200 $self->on_read (delete $self->{on_read} ) if $self->{on_read};
201 366
202 $self->start_read; 367 $self->start_read
368 if $self->{on_read};
203 369
204 $self 370 $self->{fh} && $self
205} 371}
206 372
207sub _shutdown { 373#sub _shutdown {
208 my ($self) = @_; 374# my ($self) = @_;
375#
376# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
377# $self->{_eof} = 1; # tell starttls et. al to stop trying
378#
379# &_freetls;
380#}
209 381
210 delete $self->{_rw};
211 delete $self->{_ww};
212 delete $self->{fh};
213}
214
215sub error { 382sub _error {
216 my ($self) = @_; 383 my ($self, $errno, $fatal, $message) = @_;
217 384
218 { 385 $! = $errno;
219 local $!; 386 $message ||= "$!";
220 $self->_shutdown;
221 }
222 387
223 $self->{on_error}($self)
224 if $self->{on_error}; 388 if ($self->{on_error}) {
225 389 $self->{on_error}($self, $fatal, $message);
390 $self->destroy;
391 } elsif ($self->{fh}) {
392 $self->destroy;
226 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 393 Carp::croak "AnyEvent::Handle uncaught error: $message";
394 }
227} 395}
228 396
229=item $fh = $handle->fh 397=item $fh = $handle->fh
230 398
231This method returns the file handle of the L<AnyEvent::Handle> object. 399This method returns the file handle used to create the L<AnyEvent::Handle> object.
232 400
233=cut 401=cut
234 402
235sub fh { $_[0]{fh} } 403sub fh { $_[0]{fh} }
236 404
252 420
253sub on_eof { 421sub on_eof {
254 $_[0]{on_eof} = $_[1]; 422 $_[0]{on_eof} = $_[1];
255} 423}
256 424
425=item $handle->on_timeout ($cb)
426
427Replace the current C<on_timeout> callback, or disables the callback (but
428not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
429argument and method.
430
431=cut
432
433sub on_timeout {
434 $_[0]{on_timeout} = $_[1];
435}
436
437=item $handle->autocork ($boolean)
438
439Enables or disables the current autocork behaviour (see C<autocork>
440constructor argument). Changes will only take effect on the next write.
441
442=cut
443
444sub autocork {
445 $_[0]{autocork} = $_[1];
446}
447
448=item $handle->no_delay ($boolean)
449
450Enables or disables the C<no_delay> setting (see constructor argument of
451the same name for details).
452
453=cut
454
455sub no_delay {
456 $_[0]{no_delay} = $_[1];
457
458 eval {
459 local $SIG{__DIE__};
460 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
461 };
462}
463
464=item $handle->on_starttls ($cb)
465
466Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
467
468=cut
469
470sub on_starttls {
471 $_[0]{on_starttls} = $_[1];
472}
473
474=item $handle->on_stoptls ($cb)
475
476Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
477
478=cut
479
480sub on_starttls {
481 $_[0]{on_stoptls} = $_[1];
482}
483
484#############################################################################
485
486=item $handle->timeout ($seconds)
487
488Configures (or disables) the inactivity timeout.
489
490=cut
491
492sub timeout {
493 my ($self, $timeout) = @_;
494
495 $self->{timeout} = $timeout;
496 $self->_timeout;
497}
498
499# reset the timeout watcher, as neccessary
500# also check for time-outs
501sub _timeout {
502 my ($self) = @_;
503
504 if ($self->{timeout}) {
505 my $NOW = AnyEvent->now;
506
507 # when would the timeout trigger?
508 my $after = $self->{_activity} + $self->{timeout} - $NOW;
509
510 # now or in the past already?
511 if ($after <= 0) {
512 $self->{_activity} = $NOW;
513
514 if ($self->{on_timeout}) {
515 $self->{on_timeout}($self);
516 } else {
517 $self->_error (&Errno::ETIMEDOUT);
518 }
519
520 # callback could have changed timeout value, optimise
521 return unless $self->{timeout};
522
523 # calculate new after
524 $after = $self->{timeout};
525 }
526
527 Scalar::Util::weaken $self;
528 return unless $self; # ->error could have destroyed $self
529
530 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
531 delete $self->{_tw};
532 $self->_timeout;
533 });
534 } else {
535 delete $self->{_tw};
536 }
537}
538
257############################################################################# 539#############################################################################
258 540
259=back 541=back
260 542
261=head2 WRITE QUEUE 543=head2 WRITE QUEUE
282 my ($self, $cb) = @_; 564 my ($self, $cb) = @_;
283 565
284 $self->{on_drain} = $cb; 566 $self->{on_drain} = $cb;
285 567
286 $cb->($self) 568 $cb->($self)
287 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 569 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
288} 570}
289 571
290=item $handle->push_write ($data) 572=item $handle->push_write ($data)
291 573
292Queues the given scalar to be written. You can push as much data as you 574Queues the given scalar to be written. You can push as much data as you
303 Scalar::Util::weaken $self; 585 Scalar::Util::weaken $self;
304 586
305 my $cb = sub { 587 my $cb = sub {
306 my $len = syswrite $self->{fh}, $self->{wbuf}; 588 my $len = syswrite $self->{fh}, $self->{wbuf};
307 589
308 if ($len >= 0) { 590 if (defined $len) {
309 substr $self->{wbuf}, 0, $len, ""; 591 substr $self->{wbuf}, 0, $len, "";
310 592
593 $self->{_activity} = AnyEvent->now;
594
311 $self->{on_drain}($self) 595 $self->{on_drain}($self)
312 if $self->{low_water_mark} >= length $self->{wbuf} 596 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
313 && $self->{on_drain}; 597 && $self->{on_drain};
314 598
315 delete $self->{_ww} unless length $self->{wbuf}; 599 delete $self->{_ww} unless length $self->{wbuf};
316 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) { 600 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
317 $self->error; 601 $self->_error ($!, 1);
318 } 602 }
319 }; 603 };
320 604
321 # try to write data immediately 605 # try to write data immediately
322 $cb->(); 606 $cb->() unless $self->{autocork};
323 607
324 # if still data left in wbuf, we need to poll 608 # if still data left in wbuf, we need to poll
325 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 609 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
326 if length $self->{wbuf}; 610 if length $self->{wbuf};
327 }; 611 };
341 625
342 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 626 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
343 ->($self, @_); 627 ->($self, @_);
344 } 628 }
345 629
346 if ($self->{filter_w}) { 630 if ($self->{tls}) {
347 $self->{filter_w}->($self, \$_[0]); 631 $self->{_tls_wbuf} .= $_[0];
632
633 &_dotls ($self);
348 } else { 634 } else {
349 $self->{wbuf} .= $_[0]; 635 $self->{wbuf} .= $_[0];
350 $self->_drain_wbuf; 636 $self->_drain_wbuf;
351 } 637 }
352} 638}
353 639
354=item $handle->push_write (type => @args) 640=item $handle->push_write (type => @args)
355 641
356=item $handle->unshift_write (type => @args)
357
358Instead of formatting your data yourself, you can also let this module do 642Instead of formatting your data yourself, you can also let this module do
359the job by specifying a type and type-specific arguments. 643the job by specifying a type and type-specific arguments.
360 644
361Predefined types are (if you have ideas for additional types, feel free to 645Predefined types are (if you have ideas for additional types, feel free to
362drop by and tell us): 646drop by and tell us):
366=item netstring => $string 650=item netstring => $string
367 651
368Formats the given value as netstring 652Formats the given value as netstring
369(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 653(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
370 654
371=back
372
373=cut 655=cut
374 656
375register_write_type netstring => sub { 657register_write_type netstring => sub {
376 my ($self, $string) = @_; 658 my ($self, $string) = @_;
377 659
378 sprintf "%d:%s,", (length $string), $string 660 (length $string) . ":$string,"
379}; 661};
380 662
663=item packstring => $format, $data
664
665An octet string prefixed with an encoded length. The encoding C<$format>
666uses the same format as a Perl C<pack> format, but must specify a single
667integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
668optional C<!>, C<< < >> or C<< > >> modifier).
669
670=cut
671
672register_write_type packstring => sub {
673 my ($self, $format, $string) = @_;
674
675 pack "$format/a*", $string
676};
677
678=item json => $array_or_hashref
679
680Encodes the given hash or array reference into a JSON object. Unless you
681provide your own JSON object, this means it will be encoded to JSON text
682in UTF-8.
683
684JSON objects (and arrays) are self-delimiting, so you can write JSON at
685one end of a handle and read them at the other end without using any
686additional framing.
687
688The generated JSON text is guaranteed not to contain any newlines: While
689this module doesn't need delimiters after or between JSON texts to be
690able to read them, many other languages depend on that.
691
692A simple RPC protocol that interoperates easily with others is to send
693JSON arrays (or objects, although arrays are usually the better choice as
694they mimic how function argument passing works) and a newline after each
695JSON text:
696
697 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
698 $handle->push_write ("\012");
699
700An AnyEvent::Handle receiver would simply use the C<json> read type and
701rely on the fact that the newline will be skipped as leading whitespace:
702
703 $handle->push_read (json => sub { my $array = $_[1]; ... });
704
705Other languages could read single lines terminated by a newline and pass
706this line into their JSON decoder of choice.
707
708=cut
709
710register_write_type json => sub {
711 my ($self, $ref) = @_;
712
713 require JSON;
714
715 $self->{json} ? $self->{json}->encode ($ref)
716 : JSON::encode_json ($ref)
717};
718
719=item storable => $reference
720
721Freezes the given reference using L<Storable> and writes it to the
722handle. Uses the C<nfreeze> format.
723
724=cut
725
726register_write_type storable => sub {
727 my ($self, $ref) = @_;
728
729 require Storable;
730
731 pack "w/a*", Storable::nfreeze ($ref)
732};
733
734=back
735
736=item $handle->push_shutdown
737
738Sometimes you know you want to close the socket after writing your data
739before it was actually written. One way to do that is to replace your
740C<on_drain> handler by a callback that shuts down the socket (and set
741C<low_water_mark> to C<0>). This method is a shorthand for just that, and
742replaces the C<on_drain> callback with:
743
744 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
745
746This simply shuts down the write side and signals an EOF condition to the
747the peer.
748
749You can rely on the normal read queue and C<on_eof> handling
750afterwards. This is the cleanest way to close a connection.
751
752=cut
753
754sub push_shutdown {
755 my ($self) = @_;
756
757 delete $self->{low_water_mark};
758 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
759}
760
381=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args) 761=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
382 762
383This function (not method) lets you add your own types to C<push_write>. 763This function (not method) lets you add your own types to C<push_write>.
384Whenever the given C<type> is used, C<push_write> will invoke the code 764Whenever the given C<type> is used, C<push_write> will invoke the code
385reference with the handle object and the remaining arguments. 765reference with the handle object and the remaining arguments.
386 766
405ways, the "simple" way, using only C<on_read> and the "complex" way, using 785ways, the "simple" way, using only C<on_read> and the "complex" way, using
406a queue. 786a queue.
407 787
408In the simple case, you just install an C<on_read> callback and whenever 788In the simple case, you just install an C<on_read> callback and whenever
409new data arrives, it will be called. You can then remove some data (if 789new data arrives, it will be called. You can then remove some data (if
410enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 790enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
411or not. 791leave the data there if you want to accumulate more (e.g. when only a
792partial message has been received so far).
412 793
413In the more complex case, you want to queue multiple callbacks. In this 794In the more complex case, you want to queue multiple callbacks. In this
414case, AnyEvent::Handle will call the first queued callback each time new 795case, AnyEvent::Handle will call the first queued callback each time new
415data arrives and removes it when it has done its job (see C<push_read>, 796data arrives (also the first time it is queued) and removes it when it has
416below). 797done its job (see C<push_read>, below).
417 798
418This way you can, for example, push three line-reads, followed by reading 799This way you can, for example, push three line-reads, followed by reading
419a chunk of data, and AnyEvent::Handle will execute them in order. 800a chunk of data, and AnyEvent::Handle will execute them in order.
420 801
421Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 802Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
422the specified number of bytes which give an XML datagram. 803the specified number of bytes which give an XML datagram.
423 804
424 # in the default state, expect some header bytes 805 # in the default state, expect some header bytes
425 $handle->on_read (sub { 806 $handle->on_read (sub {
426 # some data is here, now queue the length-header-read (4 octets) 807 # some data is here, now queue the length-header-read (4 octets)
427 shift->unshift_read_chunk (4, sub { 808 shift->unshift_read (chunk => 4, sub {
428 # header arrived, decode 809 # header arrived, decode
429 my $len = unpack "N", $_[1]; 810 my $len = unpack "N", $_[1];
430 811
431 # now read the payload 812 # now read the payload
432 shift->unshift_read_chunk ($len, sub { 813 shift->unshift_read (chunk => $len, sub {
433 my $xml = $_[1]; 814 my $xml = $_[1];
434 # handle xml 815 # handle xml
435 }); 816 });
436 }); 817 });
437 }); 818 });
438 819
439Example 2: Implement a client for a protocol that replies either with 820Example 2: Implement a client for a protocol that replies either with "OK"
440"OK" and another line or "ERROR" for one request, and 64 bytes for the 821and another line or "ERROR" for the first request that is sent, and 64
441second request. Due tot he availability of a full queue, we can just 822bytes for the second request. Due to the availability of a queue, we can
442pipeline sending both requests and manipulate the queue as necessary in 823just pipeline sending both requests and manipulate the queue as necessary
443the callbacks: 824in the callbacks.
444 825
445 # request one 826When the first callback is called and sees an "OK" response, it will
827C<unshift> another line-read. This line-read will be queued I<before> the
82864-byte chunk callback.
829
830 # request one, returns either "OK + extra line" or "ERROR"
446 $handle->push_write ("request 1\015\012"); 831 $handle->push_write ("request 1\015\012");
447 832
448 # we expect "ERROR" or "OK" as response, so push a line read 833 # we expect "ERROR" or "OK" as response, so push a line read
449 $handle->push_read_line (sub { 834 $handle->push_read (line => sub {
450 # if we got an "OK", we have to _prepend_ another line, 835 # if we got an "OK", we have to _prepend_ another line,
451 # so it will be read before the second request reads its 64 bytes 836 # so it will be read before the second request reads its 64 bytes
452 # which are already in the queue when this callback is called 837 # which are already in the queue when this callback is called
453 # we don't do this in case we got an error 838 # we don't do this in case we got an error
454 if ($_[1] eq "OK") { 839 if ($_[1] eq "OK") {
455 $_[0]->unshift_read_line (sub { 840 $_[0]->unshift_read (line => sub {
456 my $response = $_[1]; 841 my $response = $_[1];
457 ... 842 ...
458 }); 843 });
459 } 844 }
460 }); 845 });
461 846
462 # request two 847 # request two, simply returns 64 octets
463 $handle->push_write ("request 2\015\012"); 848 $handle->push_write ("request 2\015\012");
464 849
465 # simply read 64 bytes, always 850 # simply read 64 bytes, always
466 $handle->push_read_chunk (64, sub { 851 $handle->push_read (chunk => 64, sub {
467 my $response = $_[1]; 852 my $response = $_[1];
468 ... 853 ...
469 }); 854 });
470 855
471=over 4 856=over 4
472 857
473=cut 858=cut
474 859
475sub _drain_rbuf { 860sub _drain_rbuf {
476 my ($self) = @_; 861 my ($self) = @_;
862
863 local $self->{_in_drain} = 1;
477 864
478 if ( 865 if (
479 defined $self->{rbuf_max} 866 defined $self->{rbuf_max}
480 && $self->{rbuf_max} < length $self->{rbuf} 867 && $self->{rbuf_max} < length $self->{rbuf}
481 ) { 868 ) {
482 $! = &Errno::ENOSPC; 869 $self->_error (&Errno::ENOSPC, 1), return;
483 $self->error;
484 } 870 }
485 871
486 return if $self->{in_drain}; 872 while () {
487 local $self->{in_drain} = 1; 873 # we need to use a separate tls read buffer, as we must not receive data while
874 # we are draining the buffer, and this can only happen with TLS.
875 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
488 876
489 while (my $len = length $self->{rbuf}) { 877 my $len = length $self->{rbuf};
490 no strict 'refs'; 878
491 if (my $cb = shift @{ $self->{_queue} }) { 879 if (my $cb = shift @{ $self->{_queue} }) {
492 unless ($cb->($self)) { 880 unless ($cb->($self)) {
493 if ($self->{_eof}) { 881 if ($self->{_eof}) {
494 # no progress can be made (not enough data and no data forthcoming) 882 # no progress can be made (not enough data and no data forthcoming)
495 $! = &Errno::EPIPE; 883 $self->_error (&Errno::EPIPE, 1), return;
496 $self->error;
497 } 884 }
498 885
499 unshift @{ $self->{_queue} }, $cb; 886 unshift @{ $self->{_queue} }, $cb;
500 return; 887 last;
501 } 888 }
502 } elsif ($self->{on_read}) { 889 } elsif ($self->{on_read}) {
890 last unless $len;
891
503 $self->{on_read}($self); 892 $self->{on_read}($self);
504 893
505 if ( 894 if (
506 $self->{_eof} # if no further data will arrive
507 && $len == length $self->{rbuf} # and no data has been consumed 895 $len == length $self->{rbuf} # if no data has been consumed
508 && !@{ $self->{_queue} } # and the queue is still empty 896 && !@{ $self->{_queue} } # and the queue is still empty
509 && $self->{on_read} # and we still want to read data 897 && $self->{on_read} # but we still have on_read
510 ) { 898 ) {
899 # no further data will arrive
511 # then no progress can be made 900 # so no progress can be made
512 $! = &Errno::EPIPE; 901 $self->_error (&Errno::EPIPE, 1), return
513 $self->error; 902 if $self->{_eof};
903
904 last; # more data might arrive
514 } 905 }
515 } else { 906 } else {
516 # read side becomes idle 907 # read side becomes idle
517 delete $self->{_rw}; 908 delete $self->{_rw} unless $self->{tls};
518 return; 909 last;
519 } 910 }
520 } 911 }
521 912
522 if ($self->{_eof}) { 913 if ($self->{_eof}) {
523 $self->_shutdown; 914 if ($self->{on_eof}) {
524 $self->{on_eof}($self) 915 $self->{on_eof}($self)
525 if $self->{on_eof}; 916 } else {
917 $self->_error (0, 1, "Unexpected end-of-file");
918 }
919 }
920
921 # may need to restart read watcher
922 unless ($self->{_rw}) {
923 $self->start_read
924 if $self->{on_read} || @{ $self->{_queue} };
526 } 925 }
527} 926}
528 927
529=item $handle->on_read ($cb) 928=item $handle->on_read ($cb)
530 929
536 935
537sub on_read { 936sub on_read {
538 my ($self, $cb) = @_; 937 my ($self, $cb) = @_;
539 938
540 $self->{on_read} = $cb; 939 $self->{on_read} = $cb;
940 $self->_drain_rbuf if $cb && !$self->{_in_drain};
541} 941}
542 942
543=item $handle->rbuf 943=item $handle->rbuf
544 944
545Returns the read buffer (as a modifiable lvalue). 945Returns the read buffer (as a modifiable lvalue).
546 946
547You can access the read buffer directly as the C<< ->{rbuf} >> member, if 947You can access the read buffer directly as the C<< ->{rbuf} >>
548you want. 948member, if you want. However, the only operation allowed on the
949read buffer (apart from looking at it) is removing data from its
950beginning. Otherwise modifying or appending to it is not allowed and will
951lead to hard-to-track-down bugs.
549 952
550NOTE: The read buffer should only be used or modified if the C<on_read>, 953NOTE: The read buffer should only be used or modified if the C<on_read>,
551C<push_read> or C<unshift_read> methods are used. The other read methods 954C<push_read> or C<unshift_read> methods are used. The other read methods
552automatically manage the read buffer. 955automatically manage the read buffer.
553 956
594 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 997 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
595 ->($self, $cb, @_); 998 ->($self, $cb, @_);
596 } 999 }
597 1000
598 push @{ $self->{_queue} }, $cb; 1001 push @{ $self->{_queue} }, $cb;
599 $self->_drain_rbuf; 1002 $self->_drain_rbuf unless $self->{_in_drain};
600} 1003}
601 1004
602sub unshift_read { 1005sub unshift_read {
603 my $self = shift; 1006 my $self = shift;
604 my $cb = pop; 1007 my $cb = pop;
610 ->($self, $cb, @_); 1013 ->($self, $cb, @_);
611 } 1014 }
612 1015
613 1016
614 unshift @{ $self->{_queue} }, $cb; 1017 unshift @{ $self->{_queue} }, $cb;
615 $self->_drain_rbuf; 1018 $self->_drain_rbuf unless $self->{_in_drain};
616} 1019}
617 1020
618=item $handle->push_read (type => @args, $cb) 1021=item $handle->push_read (type => @args, $cb)
619 1022
620=item $handle->unshift_read (type => @args, $cb) 1023=item $handle->unshift_read (type => @args, $cb)
626Predefined types are (if you have ideas for additional types, feel free to 1029Predefined types are (if you have ideas for additional types, feel free to
627drop by and tell us): 1030drop by and tell us):
628 1031
629=over 4 1032=over 4
630 1033
631=item chunk => $octets, $cb->($self, $data) 1034=item chunk => $octets, $cb->($handle, $data)
632 1035
633Invoke the callback only once C<$octets> bytes have been read. Pass the 1036Invoke the callback only once C<$octets> bytes have been read. Pass the
634data read to the callback. The callback will never be called with less 1037data read to the callback. The callback will never be called with less
635data. 1038data.
636 1039
650 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 1053 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
651 1 1054 1
652 } 1055 }
653}; 1056};
654 1057
655# compatibility with older API
656sub push_read_chunk {
657 $_[0]->push_read (chunk => $_[1], $_[2]);
658}
659
660sub unshift_read_chunk {
661 $_[0]->unshift_read (chunk => $_[1], $_[2]);
662}
663
664=item line => [$eol, ]$cb->($self, $line, $eol) 1058=item line => [$eol, ]$cb->($handle, $line, $eol)
665 1059
666The callback will be called only once a full line (including the end of 1060The callback will be called only once a full line (including the end of
667line marker, C<$eol>) has been read. This line (excluding the end of line 1061line marker, C<$eol>) has been read. This line (excluding the end of line
668marker) will be passed to the callback as second argument (C<$line>), and 1062marker) will be passed to the callback as second argument (C<$line>), and
669the end of line marker as the third argument (C<$eol>). 1063the end of line marker as the third argument (C<$eol>).
683=cut 1077=cut
684 1078
685register_read_type line => sub { 1079register_read_type line => sub {
686 my ($self, $cb, $eol) = @_; 1080 my ($self, $cb, $eol) = @_;
687 1081
688 $eol = qr|(\015?\012)| if @_ < 3; 1082 if (@_ < 3) {
1083 # this is more than twice as fast as the generic code below
1084 sub {
1085 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1086
1087 $cb->($_[0], $1, $2);
1088 1
1089 }
1090 } else {
689 $eol = quotemeta $eol unless ref $eol; 1091 $eol = quotemeta $eol unless ref $eol;
690 $eol = qr|^(.*?)($eol)|s; 1092 $eol = qr|^(.*?)($eol)|s;
691 1093
692 sub { 1094 sub {
693 $_[0]{rbuf} =~ s/$eol// or return; 1095 $_[0]{rbuf} =~ s/$eol// or return;
694 1096
695 $cb->($_[0], $1, $2); 1097 $cb->($_[0], $1, $2);
1098 1
696 1 1099 }
697 } 1100 }
698}; 1101};
699 1102
700# compatibility with older API
701sub push_read_line {
702 my $self = shift;
703 $self->push_read (line => @_);
704}
705
706sub unshift_read_line {
707 my $self = shift;
708 $self->unshift_read (line => @_);
709}
710
711=item netstring => $cb->($string)
712
713A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
714
715Throws an error with C<$!> set to EBADMSG on format violations.
716
717=cut
718
719register_read_type netstring => sub {
720 my ($self, $cb) = @_;
721
722 sub {
723 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
724 if ($_[0]{rbuf} =~ /[^0-9]/) {
725 $! = &Errno::EBADMSG;
726 $self->error;
727 }
728 return;
729 }
730
731 my $len = $1;
732
733 $self->unshift_read (chunk => $len, sub {
734 my $string = $_[1];
735 $_[0]->unshift_read (chunk => 1, sub {
736 if ($_[1] eq ",") {
737 $cb->($_[0], $string);
738 } else {
739 $! = &Errno::EBADMSG;
740 $self->error;
741 }
742 });
743 });
744
745 1
746 }
747};
748
749=item regex => $accept[, $reject[, $skip], $cb->($data) 1103=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
750 1104
751Makes a regex match against the regex object C<$accept> and returns 1105Makes a regex match against the regex object C<$accept> and returns
752everything up to and including the match. 1106everything up to and including the match.
753 1107
754Example: read a single line terminated by '\n'. 1108Example: read a single line terminated by '\n'.
802 return 1; 1156 return 1;
803 } 1157 }
804 1158
805 # reject 1159 # reject
806 if ($reject && $$rbuf =~ $reject) { 1160 if ($reject && $$rbuf =~ $reject) {
807 $! = &Errno::EBADMSG; 1161 $self->_error (&Errno::EBADMSG);
808 $self->error;
809 } 1162 }
810 1163
811 # skip 1164 # skip
812 if ($skip && $$rbuf =~ $skip) { 1165 if ($skip && $$rbuf =~ $skip) {
813 $data .= substr $$rbuf, 0, $+[0], ""; 1166 $data .= substr $$rbuf, 0, $+[0], "";
815 1168
816 () 1169 ()
817 } 1170 }
818}; 1171};
819 1172
1173=item netstring => $cb->($handle, $string)
1174
1175A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1176
1177Throws an error with C<$!> set to EBADMSG on format violations.
1178
1179=cut
1180
1181register_read_type netstring => sub {
1182 my ($self, $cb) = @_;
1183
1184 sub {
1185 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1186 if ($_[0]{rbuf} =~ /[^0-9]/) {
1187 $self->_error (&Errno::EBADMSG);
1188 }
1189 return;
1190 }
1191
1192 my $len = $1;
1193
1194 $self->unshift_read (chunk => $len, sub {
1195 my $string = $_[1];
1196 $_[0]->unshift_read (chunk => 1, sub {
1197 if ($_[1] eq ",") {
1198 $cb->($_[0], $string);
1199 } else {
1200 $self->_error (&Errno::EBADMSG);
1201 }
1202 });
1203 });
1204
1205 1
1206 }
1207};
1208
1209=item packstring => $format, $cb->($handle, $string)
1210
1211An octet string prefixed with an encoded length. The encoding C<$format>
1212uses the same format as a Perl C<pack> format, but must specify a single
1213integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1214optional C<!>, C<< < >> or C<< > >> modifier).
1215
1216For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1217EPP uses a prefix of C<N> (4 octtes).
1218
1219Example: read a block of data prefixed by its length in BER-encoded
1220format (very efficient).
1221
1222 $handle->push_read (packstring => "w", sub {
1223 my ($handle, $data) = @_;
1224 });
1225
1226=cut
1227
1228register_read_type packstring => sub {
1229 my ($self, $cb, $format) = @_;
1230
1231 sub {
1232 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1233 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1234 or return;
1235
1236 $format = length pack $format, $len;
1237
1238 # bypass unshift if we already have the remaining chunk
1239 if ($format + $len <= length $_[0]{rbuf}) {
1240 my $data = substr $_[0]{rbuf}, $format, $len;
1241 substr $_[0]{rbuf}, 0, $format + $len, "";
1242 $cb->($_[0], $data);
1243 } else {
1244 # remove prefix
1245 substr $_[0]{rbuf}, 0, $format, "";
1246
1247 # read remaining chunk
1248 $_[0]->unshift_read (chunk => $len, $cb);
1249 }
1250
1251 1
1252 }
1253};
1254
1255=item json => $cb->($handle, $hash_or_arrayref)
1256
1257Reads a JSON object or array, decodes it and passes it to the
1258callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1259
1260If a C<json> object was passed to the constructor, then that will be used
1261for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1262
1263This read type uses the incremental parser available with JSON version
12642.09 (and JSON::XS version 2.2) and above. You have to provide a
1265dependency on your own: this module will load the JSON module, but
1266AnyEvent does not depend on it itself.
1267
1268Since JSON texts are fully self-delimiting, the C<json> read and write
1269types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1270the C<json> write type description, above, for an actual example.
1271
1272=cut
1273
1274register_read_type json => sub {
1275 my ($self, $cb) = @_;
1276
1277 my $json = $self->{json} ||=
1278 eval { require JSON::XS; JSON::XS->new->utf8 }
1279 || do { require JSON; JSON->new->utf8 };
1280
1281 my $data;
1282 my $rbuf = \$self->{rbuf};
1283
1284 sub {
1285 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1286
1287 if ($ref) {
1288 $self->{rbuf} = $json->incr_text;
1289 $json->incr_text = "";
1290 $cb->($self, $ref);
1291
1292 1
1293 } elsif ($@) {
1294 # error case
1295 $json->incr_skip;
1296
1297 $self->{rbuf} = $json->incr_text;
1298 $json->incr_text = "";
1299
1300 $self->_error (&Errno::EBADMSG);
1301
1302 ()
1303 } else {
1304 $self->{rbuf} = "";
1305
1306 ()
1307 }
1308 }
1309};
1310
1311=item storable => $cb->($handle, $ref)
1312
1313Deserialises a L<Storable> frozen representation as written by the
1314C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1315data).
1316
1317Raises C<EBADMSG> error if the data could not be decoded.
1318
1319=cut
1320
1321register_read_type storable => sub {
1322 my ($self, $cb) = @_;
1323
1324 require Storable;
1325
1326 sub {
1327 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1328 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1329 or return;
1330
1331 my $format = length pack "w", $len;
1332
1333 # bypass unshift if we already have the remaining chunk
1334 if ($format + $len <= length $_[0]{rbuf}) {
1335 my $data = substr $_[0]{rbuf}, $format, $len;
1336 substr $_[0]{rbuf}, 0, $format + $len, "";
1337 $cb->($_[0], Storable::thaw ($data));
1338 } else {
1339 # remove prefix
1340 substr $_[0]{rbuf}, 0, $format, "";
1341
1342 # read remaining chunk
1343 $_[0]->unshift_read (chunk => $len, sub {
1344 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1345 $cb->($_[0], $ref);
1346 } else {
1347 $self->_error (&Errno::EBADMSG);
1348 }
1349 });
1350 }
1351
1352 1
1353 }
1354};
1355
820=back 1356=back
821 1357
822=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args) 1358=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
823 1359
824This function (not method) lets you add your own types to C<push_read>. 1360This function (not method) lets you add your own types to C<push_read>.
825 1361
826Whenever the given C<type> is used, C<push_read> will invoke the code 1362Whenever the given C<type> is used, C<push_read> will invoke the code
827reference with the handle object, the callback and the remaining 1363reference with the handle object, the callback and the remaining
829 1365
830The code reference is supposed to return a callback (usually a closure) 1366The code reference is supposed to return a callback (usually a closure)
831that works as a plain read callback (see C<< ->push_read ($cb) >>). 1367that works as a plain read callback (see C<< ->push_read ($cb) >>).
832 1368
833It should invoke the passed callback when it is done reading (remember to 1369It should invoke the passed callback when it is done reading (remember to
834pass C<$self> as first argument as all other callbacks do that). 1370pass C<$handle> as first argument as all other callbacks do that).
835 1371
836Note that this is a function, and all types registered this way will be 1372Note that this is a function, and all types registered this way will be
837global, so try to use unique names. 1373global, so try to use unique names.
838 1374
839For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1375For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
842=item $handle->stop_read 1378=item $handle->stop_read
843 1379
844=item $handle->start_read 1380=item $handle->start_read
845 1381
846In rare cases you actually do not want to read anything from the 1382In rare cases you actually do not want to read anything from the
847socket. In this case you can call C<stop_read>. Neither C<on_read> no 1383socket. In this case you can call C<stop_read>. Neither C<on_read> nor
848any queued callbacks will be executed then. To start reading again, call 1384any queued callbacks will be executed then. To start reading again, call
849C<start_read>. 1385C<start_read>.
850 1386
1387Note that AnyEvent::Handle will automatically C<start_read> for you when
1388you change the C<on_read> callback or push/unshift a read callback, and it
1389will automatically C<stop_read> for you when neither C<on_read> is set nor
1390there are any read requests in the queue.
1391
1392These methods will have no effect when in TLS mode (as TLS doesn't support
1393half-duplex connections).
1394
851=cut 1395=cut
852 1396
853sub stop_read { 1397sub stop_read {
854 my ($self) = @_; 1398 my ($self) = @_;
855 1399
856 delete $self->{_rw}; 1400 delete $self->{_rw} unless $self->{tls};
857} 1401}
858 1402
859sub start_read { 1403sub start_read {
860 my ($self) = @_; 1404 my ($self) = @_;
861 1405
862 unless ($self->{_rw} || $self->{_eof}) { 1406 unless ($self->{_rw} || $self->{_eof}) {
863 Scalar::Util::weaken $self; 1407 Scalar::Util::weaken $self;
864 1408
865 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1409 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
866 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1410 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
867 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1411 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
868 1412
869 if ($len > 0) { 1413 if ($len > 0) {
870 $self->{filter_r} 1414 $self->{_activity} = AnyEvent->now;
871 ? $self->{filter_r}->($self, $rbuf) 1415
872 : $self->_drain_rbuf; 1416 if ($self->{tls}) {
1417 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1418
1419 &_dotls ($self);
1420 } else {
1421 $self->_drain_rbuf unless $self->{_in_drain};
1422 }
873 1423
874 } elsif (defined $len) { 1424 } elsif (defined $len) {
875 delete $self->{_rw}; 1425 delete $self->{_rw};
876 $self->{_eof} = 1; 1426 $self->{_eof} = 1;
877 $self->_drain_rbuf; 1427 $self->_drain_rbuf unless $self->{_in_drain};
878 1428
879 } elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) { 1429 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
880 return $self->error; 1430 return $self->_error ($!, 1);
881 } 1431 }
882 }); 1432 });
883 } 1433 }
884} 1434}
885 1435
1436our $ERROR_SYSCALL;
1437our $ERROR_WANT_READ;
1438
1439sub _tls_error {
1440 my ($self, $err) = @_;
1441
1442 return $self->_error ($!, 1)
1443 if $err == Net::SSLeay::ERROR_SYSCALL ();
1444
1445 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1446
1447 # reduce error string to look less scary
1448 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1449
1450 if ($self->{_on_starttls}) {
1451 (delete $self->{_on_starttls})->($self, undef, $err);
1452 &_freetls;
1453 } else {
1454 &_freetls;
1455 $self->_error (&Errno::EPROTO, 1, $err);
1456 }
1457}
1458
1459# poll the write BIO and send the data if applicable
1460# also decode read data if possible
1461# this is basiclaly our TLS state machine
1462# more efficient implementations are possible with openssl,
1463# but not with the buggy and incomplete Net::SSLeay.
886sub _dotls { 1464sub _dotls {
887 my ($self) = @_; 1465 my ($self) = @_;
888 1466
1467 my $tmp;
1468
889 if (length $self->{_tls_wbuf}) { 1469 if (length $self->{_tls_wbuf}) {
890 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1470 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
891 substr $self->{_tls_wbuf}, 0, $len, ""; 1471 substr $self->{_tls_wbuf}, 0, $tmp, "";
892 } 1472 }
893 }
894 1473
1474 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1475 return $self->_tls_error ($tmp)
1476 if $tmp != $ERROR_WANT_READ
1477 && ($tmp != $ERROR_SYSCALL || $!);
1478 }
1479
1480 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1481 unless (length $tmp) {
1482 $self->{_on_starttls}
1483 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1484 &_freetls;
1485
1486 if ($self->{on_stoptls}) {
1487 $self->{on_stoptls}($self);
1488 return;
1489 } else {
1490 # let's treat SSL-eof as we treat normal EOF
1491 delete $self->{_rw};
1492 $self->{_eof} = 1;
1493 }
1494 }
1495
1496 $self->{_tls_rbuf} .= $tmp;
1497 $self->_drain_rbuf unless $self->{_in_drain};
1498 $self->{tls} or return; # tls session might have gone away in callback
1499 }
1500
1501 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1502 return $self->_tls_error ($tmp)
1503 if $tmp != $ERROR_WANT_READ
1504 && ($tmp != $ERROR_SYSCALL || $!);
1505
895 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1506 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
896 $self->{wbuf} .= $buf; 1507 $self->{wbuf} .= $tmp;
897 $self->_drain_wbuf; 1508 $self->_drain_wbuf;
898 } 1509 }
899 1510
900 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) { 1511 $self->{_on_starttls}
901 $self->{rbuf} .= $buf; 1512 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
902 $self->_drain_rbuf; 1513 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
903 }
904
905 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
906
907 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
908 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
909 $self->error;
910 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
911 $! = &Errno::EIO;
912 $self->error;
913 }
914
915 # all others are fine for our purposes
916 }
917} 1514}
918 1515
919=item $handle->starttls ($tls[, $tls_ctx]) 1516=item $handle->starttls ($tls[, $tls_ctx])
920 1517
921Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1518Instead of starting TLS negotiation immediately when the AnyEvent::Handle
923C<starttls>. 1520C<starttls>.
924 1521
925The first argument is the same as the C<tls> constructor argument (either 1522The first argument is the same as the C<tls> constructor argument (either
926C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1523C<"connect">, C<"accept"> or an existing Net::SSLeay object).
927 1524
928The second argument is the optional C<Net::SSLeay::CTX> object that is 1525The second argument is the optional C<AnyEvent::TLS> object that is used
929used when AnyEvent::Handle has to create its own TLS connection object. 1526when AnyEvent::Handle has to create its own TLS connection object, or
1527a hash reference with C<< key => value >> pairs that will be used to
1528construct a new context.
930 1529
931The TLS connection object will end up in C<< $handle->{tls} >> after this 1530The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
932call and can be used or changed to your liking. Note that the handshake 1531context in C<< $handle->{tls_ctx} >> after this call and can be used or
933might have already started when this function returns. 1532changed to your liking. Note that the handshake might have already started
1533when this function returns.
934 1534
935=cut 1535If it an error to start a TLS handshake more than once per
1536AnyEvent::Handle object (this is due to bugs in OpenSSL).
936 1537
937# TODO: maybe document... 1538=cut
1539
1540our %TLS_CACHE; #TODO not yet documented, should we?
1541
938sub starttls { 1542sub starttls {
939 my ($self, $ssl, $ctx) = @_; 1543 my ($self, $ssl, $ctx) = @_;
940 1544
941 $self->stoptls; 1545 require Net::SSLeay;
942 1546
943 if ($ssl eq "accept") { 1547 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
944 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1548 if $self->{tls};
945 Net::SSLeay::set_accept_state ($ssl); 1549
946 } elsif ($ssl eq "connect") { 1550 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
947 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1551 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
948 Net::SSLeay::set_connect_state ($ssl); 1552
1553 $ctx ||= $self->{tls_ctx};
1554
1555 if ("HASH" eq ref $ctx) {
1556 require AnyEvent::TLS;
1557
1558 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
1559
1560 if ($ctx->{cache}) {
1561 my $key = $ctx+0;
1562 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1563 } else {
1564 $ctx = new AnyEvent::TLS %$ctx;
1565 }
1566 }
949 } 1567
950 1568 $self->{tls_ctx} = $ctx || TLS_CTX ();
951 $self->{tls} = $ssl; 1569 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});
952 1570
953 # basically, this is deep magic (because SSL_read should have the same issues) 1571 # basically, this is deep magic (because SSL_read should have the same issues)
954 # but the openssl maintainers basically said: "trust us, it just works". 1572 # but the openssl maintainers basically said: "trust us, it just works".
955 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1573 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
956 # and mismaintained ssleay-module doesn't even offer them). 1574 # and mismaintained ssleay-module doesn't even offer them).
957 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1575 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1576 #
1577 # in short: this is a mess.
1578 #
1579 # note that we do not try to keep the length constant between writes as we are required to do.
1580 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1581 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1582 # have identity issues in that area.
958 Net::SSLeay::CTX_set_mode ($self->{tls}, 1583# Net::SSLeay::CTX_set_mode ($ssl,
959 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1584# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
960 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1585# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1586 Net::SSLeay::CTX_set_mode ($ssl, 1|2);
961 1587
962 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1588 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
963 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1589 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
964 1590
965 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 1591 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
966 1592
967 $self->{filter_w} = sub { 1593 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
968 $_[0]{_tls_wbuf} .= ${$_[1]}; 1594 if $self->{on_starttls};
969 &_dotls; 1595
970 }; 1596 &_dotls; # need to trigger the initial handshake
971 $self->{filter_r} = sub { 1597 $self->start_read; # make sure we actually do read
972 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
973 &_dotls;
974 };
975} 1598}
976 1599
977=item $handle->stoptls 1600=item $handle->stoptls
978 1601
979Destroys the SSL connection, if any. Partial read or write data will be 1602Shuts down the SSL connection - this makes a proper EOF handshake by
980lost. 1603sending a close notify to the other side, but since OpenSSL doesn't
1604support non-blocking shut downs, it is not possible to re-use the stream
1605afterwards.
981 1606
982=cut 1607=cut
983 1608
984sub stoptls { 1609sub stoptls {
985 my ($self) = @_; 1610 my ($self) = @_;
986 1611
987 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1612 if ($self->{tls}) {
1613 Net::SSLeay::shutdown ($self->{tls});
988 1614
989 delete $self->{_rbio}; 1615 &_dotls;
990 delete $self->{_wbio}; 1616
991 delete $self->{_tls_wbuf}; 1617# # we don't give a shit. no, we do, but we can't. no...#d#
992 delete $self->{filter_r}; 1618# # we, we... have to use openssl :/#d#
993 delete $self->{filter_w}; 1619# &_freetls;#d#
1620 }
1621}
1622
1623sub _freetls {
1624 my ($self) = @_;
1625
1626 return unless $self->{tls};
1627
1628 $self->{tls_ctx}->_put_session (delete $self->{tls});
1629
1630 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
994} 1631}
995 1632
996sub DESTROY { 1633sub DESTROY {
997 my $self = shift; 1634 my ($self) = @_;
998 1635
999 $self->stoptls; 1636 &_freetls;
1637
1638 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1639
1640 if ($linger && length $self->{wbuf}) {
1641 my $fh = delete $self->{fh};
1642 my $wbuf = delete $self->{wbuf};
1643
1644 my @linger;
1645
1646 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1647 my $len = syswrite $fh, $wbuf, length $wbuf;
1648
1649 if ($len > 0) {
1650 substr $wbuf, 0, $len, "";
1651 } else {
1652 @linger = (); # end
1653 }
1654 });
1655 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1656 @linger = ();
1657 });
1658 }
1659}
1660
1661=item $handle->destroy
1662
1663Shuts down the handle object as much as possible - this call ensures that
1664no further callbacks will be invoked and as many resources as possible
1665will be freed. You must not call any methods on the object afterwards.
1666
1667Normally, you can just "forget" any references to an AnyEvent::Handle
1668object and it will simply shut down. This works in fatal error and EOF
1669callbacks, as well as code outside. It does I<NOT> work in a read or write
1670callback, so when you want to destroy the AnyEvent::Handle object from
1671within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1672that case.
1673
1674Destroying the handle object in this way has the advantage that callbacks
1675will be removed as well, so if those are the only reference holders (as
1676is common), then one doesn't need to do anything special to break any
1677reference cycles.
1678
1679The handle might still linger in the background and write out remaining
1680data, as specified by the C<linger> option, however.
1681
1682=cut
1683
1684sub destroy {
1685 my ($self) = @_;
1686
1687 $self->DESTROY;
1688 %$self = ();
1000} 1689}
1001 1690
1002=item AnyEvent::Handle::TLS_CTX 1691=item AnyEvent::Handle::TLS_CTX
1003 1692
1004This function creates and returns the Net::SSLeay::CTX object used by 1693This function creates and returns the AnyEvent::TLS object used by default
1005default for TLS mode. 1694for TLS mode.
1006 1695
1007The context is created like this: 1696The context is created by calling L<AnyEvent::TLS> without any arguments.
1008
1009 Net::SSLeay::load_error_strings;
1010 Net::SSLeay::SSLeay_add_ssl_algorithms;
1011 Net::SSLeay::randomize;
1012
1013 my $CTX = Net::SSLeay::CTX_new;
1014
1015 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1016 1697
1017=cut 1698=cut
1018 1699
1019our $TLS_CTX; 1700our $TLS_CTX;
1020 1701
1021sub TLS_CTX() { 1702sub TLS_CTX() {
1022 $TLS_CTX || do { 1703 $TLS_CTX ||= do {
1023 require Net::SSLeay; 1704 require AnyEvent::TLS;
1024 1705
1025 Net::SSLeay::load_error_strings (); 1706 new AnyEvent::TLS
1026 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1027 Net::SSLeay::randomize ();
1028
1029 $TLS_CTX = Net::SSLeay::CTX_new ();
1030
1031 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1032
1033 $TLS_CTX
1034 } 1707 }
1035} 1708}
1036 1709
1037=back 1710=back
1711
1712
1713=head1 NONFREQUENTLY ASKED QUESTIONS
1714
1715=over 4
1716
1717=item I C<undef> the AnyEvent::Handle reference inside my callback and
1718still get further invocations!
1719
1720That's because AnyEvent::Handle keeps a reference to itself when handling
1721read or write callbacks.
1722
1723It is only safe to "forget" the reference inside EOF or error callbacks,
1724from within all other callbacks, you need to explicitly call the C<<
1725->destroy >> method.
1726
1727=item I get different callback invocations in TLS mode/Why can't I pause
1728reading?
1729
1730Unlike, say, TCP, TLS connections do not consist of two independent
1731communication channels, one for each direction. Or put differently. The
1732read and write directions are not independent of each other: you cannot
1733write data unless you are also prepared to read, and vice versa.
1734
1735This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1736callback invocations when you are not expecting any read data - the reason
1737is that AnyEvent::Handle always reads in TLS mode.
1738
1739During the connection, you have to make sure that you always have a
1740non-empty read-queue, or an C<on_read> watcher. At the end of the
1741connection (or when you no longer want to use it) you can call the
1742C<destroy> method.
1743
1744=item How do I read data until the other side closes the connection?
1745
1746If you just want to read your data into a perl scalar, the easiest way
1747to achieve this is by setting an C<on_read> callback that does nothing,
1748clearing the C<on_eof> callback and in the C<on_error> callback, the data
1749will be in C<$_[0]{rbuf}>:
1750
1751 $handle->on_read (sub { });
1752 $handle->on_eof (undef);
1753 $handle->on_error (sub {
1754 my $data = delete $_[0]{rbuf};
1755 });
1756
1757The reason to use C<on_error> is that TCP connections, due to latencies
1758and packets loss, might get closed quite violently with an error, when in
1759fact, all data has been received.
1760
1761It is usually better to use acknowledgements when transferring data,
1762to make sure the other side hasn't just died and you got the data
1763intact. This is also one reason why so many internet protocols have an
1764explicit QUIT command.
1765
1766=item I don't want to destroy the handle too early - how do I wait until
1767all data has been written?
1768
1769After writing your last bits of data, set the C<on_drain> callback
1770and destroy the handle in there - with the default setting of
1771C<low_water_mark> this will be called precisely when all data has been
1772written to the socket:
1773
1774 $handle->push_write (...);
1775 $handle->on_drain (sub {
1776 warn "all data submitted to the kernel\n";
1777 undef $handle;
1778 });
1779
1780If you just want to queue some data and then signal EOF to the other side,
1781consider using C<< ->push_shutdown >> instead.
1782
1783=item I want to contact a TLS/SSL server, I don't care about security.
1784
1785If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1786simply connect to it and then create the AnyEvent::Handle with the C<tls>
1787parameter:
1788
1789 tcp_connect $host, $port, sub {
1790 my ($fh) = @_;
1791
1792 my $handle = new AnyEvent::Handle
1793 fh => $fh,
1794 tls => "connect",
1795 on_error => sub { ... };
1796
1797 $handle->push_write (...);
1798 };
1799
1800=item I want to contact a TLS/SSL server, I do care about security.
1801
1802Then you should additionally enable certificate verification, including
1803peername verification, if the protocol you use supports it (see
1804L<AnyEvent::TLS>, C<verify_peername>).
1805
1806E.g. for HTTPS:
1807
1808 tcp_connect $host, $port, sub {
1809 my ($fh) = @_;
1810
1811 my $handle = new AnyEvent::Handle
1812 fh => $fh,
1813 peername => $host,
1814 tls => "connect",
1815 tls_ctx => { verify => 1, verify_peername => "https" },
1816 ...
1817
1818Note that you must specify the hostname you connected to (or whatever
1819"peername" the protocol needs) as the C<peername> argument, otherwise no
1820peername verification will be done.
1821
1822The above will use the system-dependent default set of trusted CA
1823certificates. If you want to check against a specific CA, add the
1824C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
1825
1826 tls_ctx => {
1827 verify => 1,
1828 verify_peername => "https",
1829 ca_file => "my-ca-cert.pem",
1830 },
1831
1832=item I want to create a TLS/SSL server, how do I do that?
1833
1834Well, you first need to get a server certificate and key. You have
1835three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
1836self-signed certificate (cheap. check the search engine of your choice,
1837there are many tutorials on the net) or c) make your own CA (tinyca2 is a
1838nice program for that purpose).
1839
1840Then create a file with your private key (in PEM format, see
1841L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
1842file should then look like this:
1843
1844 -----BEGIN RSA PRIVATE KEY-----
1845 ...header data
1846 ... lots of base64'y-stuff
1847 -----END RSA PRIVATE KEY-----
1848
1849 -----BEGIN CERTIFICATE-----
1850 ... lots of base64'y-stuff
1851 -----END CERTIFICATE-----
1852
1853The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
1854specify this file as C<cert_file>:
1855
1856 tcp_server undef, $port, sub {
1857 my ($fh) = @_;
1858
1859 my $handle = new AnyEvent::Handle
1860 fh => $fh,
1861 tls => "accept",
1862 tls_ctx => { cert_file => "my-server-keycert.pem" },
1863 ...
1864
1865When you have intermediate CA certificates that your clients might not
1866know about, just append them to the C<cert_file>.
1867
1868=back
1869
1038 1870
1039=head1 SUBCLASSING AnyEvent::Handle 1871=head1 SUBCLASSING AnyEvent::Handle
1040 1872
1041In many cases, you might want to subclass AnyEvent::Handle. 1873In many cases, you might want to subclass AnyEvent::Handle.
1042 1874
1046=over 4 1878=over 4
1047 1879
1048=item * all constructor arguments become object members. 1880=item * all constructor arguments become object members.
1049 1881
1050At least initially, when you pass a C<tls>-argument to the constructor it 1882At least initially, when you pass a C<tls>-argument to the constructor it
1051will end up in C<< $handle->{tls} >>. Those members might be changes or 1883will end up in C<< $handle->{tls} >>. Those members might be changed or
1052mutated later on (for example C<tls> will hold the TLS connection object). 1884mutated later on (for example C<tls> will hold the TLS connection object).
1053 1885
1054=item * other object member names are prefixed with an C<_>. 1886=item * other object member names are prefixed with an C<_>.
1055 1887
1056All object members not explicitly documented (internal use) are prefixed 1888All object members not explicitly documented (internal use) are prefixed

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