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Revision 1.20 by elmex, Sat May 24 08:16:50 2008 UTC vs.
Revision 1.158 by root, Fri Jul 24 08:40:35 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
17This module is experimental.
18
19=cut 14=cut
20 15
21our $VERSION = '0.04'; 16our $VERSION = 4.86;
22 17
23=head1 SYNOPSIS 18=head1 SYNOPSIS
24 19
25 use AnyEvent; 20 use AnyEvent;
26 use AnyEvent::Handle; 21 use AnyEvent::Handle;
27 22
28 my $cv = AnyEvent->condvar; 23 my $cv = AnyEvent->condvar;
29 24
30 my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN); 25 my $hdl; $hdl = new AnyEvent::Handle
31
32 #TODO
33
34 # or use the constructor to pass the callback:
35
36 my $ae_fh2 =
37 AnyEvent::Handle->new (
38 fh => \*STDIN, 26 fh => \*STDIN,
39 on_eof => sub { 27 on_error => sub {
40 $cv->broadcast; 28 my ($hdl, $fatal, $msg) = @_;
41 }, 29 warn "got error $msg\n";
42 #TODO 30 $hdl->destroy;
31 $cv->send;
43 ); 32 );
44 33
45 $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;
46 45
47=head1 DESCRIPTION 46=head1 DESCRIPTION
48 47
49This 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
50filehandles. For utility functions for doing non-blocking connects and accepts 49filehandles. For utility functions for doing non-blocking connects and accepts
51on sockets see L<AnyEvent::Util>. 50on sockets see L<AnyEvent::Util>.
52 51
52The L<AnyEvent::Intro> tutorial contains some well-documented
53AnyEvent::Handle examples.
54
53In the following, when the documentation refers to of "bytes" then this 55In the following, when the documentation refers to of "bytes" then this
54means characters. As sysread and syswrite are used for all I/O, their 56means characters. As sysread and syswrite are used for all I/O, their
55treatment of characters applies to this module as well. 57treatment of characters applies to this module as well.
56 58
57All callbacks will be invoked with the handle object as their first 59All callbacks will be invoked with the handle object as their first
59 61
60=head1 METHODS 62=head1 METHODS
61 63
62=over 4 64=over 4
63 65
64=item B<new (%args)> 66=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
65 67
66The constructor supports these arguments (all as key => value pairs). 68The constructor supports these arguments (all as C<< key => value >> pairs).
67 69
68=over 4 70=over 4
69 71
70=item fh => $filehandle [MANDATORY] 72=item fh => $filehandle [MANDATORY]
71 73
74#=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
75
72The filehandle this L<AnyEvent::Handle> object will operate on. 76The filehandle this L<AnyEvent::Handle> object will operate on.
73
74NOTE: The filehandle will be set to non-blocking (using 77NOTE: The filehandle will be set to non-blocking mode (using
75AnyEvent::Util::fh_nonblocking). 78C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
79that mode.
76 80
81#=item connect => [$host, $service]
82#
83# You have to specify either this parameter, or C<connect>, below.
84#Try to connect to the specified host and service (port), using
85#C<AnyEvent::Socket::tcp_connect>.
86#
87#When this
88
77=item on_eof => $cb->($self) 89=item on_eof => $cb->($handle)
78 90
79Set the callback to be called on EOF. 91Set the callback to be called when an end-of-file condition is detected,
92i.e. in the case of a socket, when the other side has closed the
93connection cleanly, and there are no outstanding read requests in the
94queue (if there are read requests, then an EOF counts as an unexpected
95connection close and will be flagged as an error).
80 96
81While not mandatory, it is highly recommended to set an eof callback, 97For sockets, this just means that the other side has stopped sending data,
82otherwise you might end up with a closed socket while you are still 98you can still try to write data, and, in fact, one can return from the EOF
83waiting for data. 99callback and continue writing data, as only the read part has been shut
100down.
84 101
85=item on_error => $cb->($self) 102If an EOF condition has been detected but no C<on_eof> callback has been
103set, then a fatal error will be raised with C<$!> set to <0>.
86 104
105=item on_error => $cb->($handle, $fatal, $message)
106
87This is the fatal error callback, that is called when, well, a fatal error 107This is the error callback, which is called when, well, some error
88occurs, such as not being able to resolve the hostname, failure to connect 108occured, such as not being able to resolve the hostname, failure to
89or a read error. 109connect or a read error.
90 110
91The object will not be in a usable state when this callback has been 111Some errors are fatal (which is indicated by C<$fatal> being true). On
92called. 112fatal errors the handle object will be destroyed (by a call to C<< ->
113destroy >>) after invoking the error callback (which means you are free to
114examine the handle object). Examples of fatal errors are an EOF condition
115with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors.
116
117AnyEvent::Handle tries to find an appropriate error code for you to check
118against, but in some cases (TLS errors), this does not work well. It is
119recommended to always output the C<$message> argument in human-readable
120error messages (it's usually the same as C<"$!">).
121
122Non-fatal errors can be retried by simply returning, but it is recommended
123to simply ignore this parameter and instead abondon the handle object
124when this callback is invoked. Examples of non-fatal errors are timeouts
125C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
93 126
94On callback entrance, the value of C<$!> contains the operating system 127On callback entrance, the value of C<$!> contains the operating system
95error (or C<ENOSPC> or C<EPIPE>). 128error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
129C<EPROTO>).
96 130
97While not mandatory, it is I<highly> recommended to set this callback, as 131While not mandatory, it is I<highly> recommended to set this callback, as
98you will not be notified of errors otherwise. The default simply calls 132you will not be notified of errors otherwise. The default simply calls
99die. 133C<croak>.
100 134
101=item on_read => $cb->($self) 135=item on_read => $cb->($handle)
102 136
103This sets the default read callback, which is called when data arrives 137This sets the default read callback, which is called when data arrives
104and no read request is in the queue. 138and no read request is in the queue (unlike read queue callbacks, this
139callback will only be called when at least one octet of data is in the
140read buffer).
105 141
106To access (and remove data from) the read buffer, use the C<< ->rbuf >> 142To access (and remove data from) the read buffer, use the C<< ->rbuf >>
107method or access the C<$self->{rbuf}> member directly. 143method or access the C<< $handle->{rbuf} >> member directly. Note that you
144must not enlarge or modify the read buffer, you can only remove data at
145the beginning from it.
108 146
109When an EOF condition is detected then AnyEvent::Handle will first try to 147When an EOF condition is detected then AnyEvent::Handle will first try to
110feed all the remaining data to the queued callbacks and C<on_read> before 148feed all the remaining data to the queued callbacks and C<on_read> before
111calling the C<on_eof> callback. If no progress can be made, then a fatal 149calling the C<on_eof> callback. If no progress can be made, then a fatal
112error will be raised (with C<$!> set to C<EPIPE>). 150error will be raised (with C<$!> set to C<EPIPE>).
113 151
152Note that, unlike requests in the read queue, an C<on_read> callback
153doesn't mean you I<require> some data: if there is an EOF and there
154are outstanding read requests then an error will be flagged. With an
155C<on_read> callback, the C<on_eof> callback will be invoked.
156
114=item on_drain => $cb->() 157=item on_drain => $cb->($handle)
115 158
116This sets the callback that is called when the write buffer becomes empty 159This sets the callback that is called when the write buffer becomes empty
117(or when the callback is set and the buffer is empty already). 160(or when the callback is set and the buffer is empty already).
118 161
119To append to the write buffer, use the C<< ->push_write >> method. 162To append to the write buffer, use the C<< ->push_write >> method.
120 163
164This callback is useful when you don't want to put all of your write data
165into the queue at once, for example, when you want to write the contents
166of some file to the socket you might not want to read the whole file into
167memory and push it into the queue, but instead only read more data from
168the file when the write queue becomes empty.
169
170=item timeout => $fractional_seconds
171
172If non-zero, then this enables an "inactivity" timeout: whenever this many
173seconds pass without a successful read or write on the underlying file
174handle, the C<on_timeout> callback will be invoked (and if that one is
175missing, a non-fatal C<ETIMEDOUT> error will be raised).
176
177Note that timeout processing is also active when you currently do not have
178any outstanding read or write requests: If you plan to keep the connection
179idle then you should disable the timout temporarily or ignore the timeout
180in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
181restart the timeout.
182
183Zero (the default) disables this timeout.
184
185=item on_timeout => $cb->($handle)
186
187Called whenever the inactivity timeout passes. If you return from this
188callback, then the timeout will be reset as if some activity had happened,
189so this condition is not fatal in any way.
190
121=item rbuf_max => <bytes> 191=item rbuf_max => <bytes>
122 192
123If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 193If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
124when the read buffer ever (strictly) exceeds this size. This is useful to 194when the read buffer ever (strictly) exceeds this size. This is useful to
125avoid denial-of-service attacks. 195avoid some forms of denial-of-service attacks.
126 196
127For example, a server accepting connections from untrusted sources should 197For example, a server accepting connections from untrusted sources should
128be configured to accept only so-and-so much data that it cannot act on 198be configured to accept only so-and-so much data that it cannot act on
129(for example, when expecting a line, an attacker could send an unlimited 199(for example, when expecting a line, an attacker could send an unlimited
130amount of data without a callback ever being called as long as the line 200amount of data without a callback ever being called as long as the line
131isn't finished). 201isn't finished).
132 202
203=item autocork => <boolean>
204
205When disabled (the default), then C<push_write> will try to immediately
206write the data to the handle, if possible. This avoids having to register
207a write watcher and wait for the next event loop iteration, but can
208be inefficient if you write multiple small chunks (on the wire, this
209disadvantage is usually avoided by your kernel's nagle algorithm, see
210C<no_delay>, but this option can save costly syscalls).
211
212When enabled, then writes will always be queued till the next event loop
213iteration. This is efficient when you do many small writes per iteration,
214but less efficient when you do a single write only per iteration (or when
215the write buffer often is full). It also increases write latency.
216
217=item no_delay => <boolean>
218
219When doing small writes on sockets, your operating system kernel might
220wait a bit for more data before actually sending it out. This is called
221the Nagle algorithm, and usually it is beneficial.
222
223In some situations you want as low a delay as possible, which can be
224accomplishd by setting this option to a true value.
225
226The default is your opertaing system's default behaviour (most likely
227enabled), this option explicitly enables or disables it, if possible.
228
133=item read_size => <bytes> 229=item read_size => <bytes>
134 230
135The default read block size (the amount of bytes this module will try to read 231The default read block size (the amount of bytes this module will
136on each [loop iteration). Default: C<4096>. 232try to read during each loop iteration, which affects memory
233requirements). Default: C<8192>.
137 234
138=item low_water_mark => <bytes> 235=item low_water_mark => <bytes>
139 236
140Sets the amount of bytes (default: C<0>) that make up an "empty" write 237Sets the amount of bytes (default: C<0>) that make up an "empty" write
141buffer: If the write reaches this size or gets even samller it is 238buffer: If the write reaches this size or gets even samller it is
142considered empty. 239considered empty.
143 240
241Sometimes it can be beneficial (for performance reasons) to add data to
242the write buffer before it is fully drained, but this is a rare case, as
243the operating system kernel usually buffers data as well, so the default
244is good in almost all cases.
245
246=item linger => <seconds>
247
248If non-zero (default: C<3600>), then the destructor of the
249AnyEvent::Handle object will check whether there is still outstanding
250write data and will install a watcher that will write this data to the
251socket. No errors will be reported (this mostly matches how the operating
252system treats outstanding data at socket close time).
253
254This will not work for partial TLS data that could not be encoded
255yet. This data will be lost. Calling the C<stoptls> method in time might
256help.
257
258=item peername => $string
259
260A string used to identify the remote site - usually the DNS hostname
261(I<not> IDN!) used to create the connection, rarely the IP address.
262
263Apart from being useful in error messages, this string is also used in TLS
264peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
265verification will be skipped when C<peername> is not specified or
266C<undef>.
267
144=item tls => "accept" | "connect" | Net::SSLeay::SSL object 268=item tls => "accept" | "connect" | Net::SSLeay::SSL object
145 269
146When this parameter is given, it enables TLS (SSL) mode, that means it 270When this parameter is given, it enables TLS (SSL) mode, that means
147will start making tls handshake and will transparently encrypt/decrypt 271AnyEvent will start a TLS handshake as soon as the conenction has been
148data. 272established and will transparently encrypt/decrypt data afterwards.
149 273
150For the TLS server side, use C<accept>, and for the TLS client side of a 274All TLS protocol errors will be signalled as C<EPROTO>, with an
151connection, use C<connect> mode. 275appropriate error message.
276
277TLS mode requires Net::SSLeay to be installed (it will be loaded
278automatically when you try to create a TLS handle): this module doesn't
279have a dependency on that module, so if your module requires it, you have
280to add the dependency yourself.
281
282Unlike TCP, TLS has a server and client side: for the TLS server side, use
283C<accept>, and for the TLS client side of a connection, use C<connect>
284mode.
152 285
153You can also provide your own TLS connection object, but you have 286You can also provide your own TLS connection object, but you have
154to make sure that you call either C<Net::SSLeay::set_connect_state> 287to make sure that you call either C<Net::SSLeay::set_connect_state>
155or C<Net::SSLeay::set_accept_state> on it before you pass it to 288or C<Net::SSLeay::set_accept_state> on it before you pass it to
156AnyEvent::Handle. 289AnyEvent::Handle. Also, this module will take ownership of this connection
290object.
157 291
158=item tls_ctx => $ssl_ctx 292At some future point, AnyEvent::Handle might switch to another TLS
293implementation, then the option to use your own session object will go
294away.
159 295
296B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
297passing in the wrong integer will lead to certain crash. This most often
298happens when one uses a stylish C<< tls => 1 >> and is surprised about the
299segmentation fault.
300
301See the C<< ->starttls >> method for when need to start TLS negotiation later.
302
303=item tls_ctx => $anyevent_tls
304
160Use the given Net::SSLeay::CTX object to create the new TLS connection 305Use the given C<AnyEvent::TLS> object to create the new TLS connection
161(unless a connection object was specified directly). If this parameter is 306(unless a connection object was specified directly). If this parameter is
162missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 307missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
163 308
309Instead of an object, you can also specify a hash reference with C<< key
310=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
311new TLS context object.
312
313=item on_starttls => $cb->($handle, $success[, $error_message])
314
315This callback will be invoked when the TLS/SSL handshake has finished. If
316C<$success> is true, then the TLS handshake succeeded, otherwise it failed
317(C<on_stoptls> will not be called in this case).
318
319The session in C<< $handle->{tls} >> can still be examined in this
320callback, even when the handshake was not successful.
321
322TLS handshake failures will not cause C<on_error> to be invoked when this
323callback is in effect, instead, the error message will be passed to C<on_starttls>.
324
325Without this callback, handshake failures lead to C<on_error> being
326called, as normal.
327
328Note that you cannot call C<starttls> right again in this callback. If you
329need to do that, start an zero-second timer instead whose callback can
330then call C<< ->starttls >> again.
331
332=item on_stoptls => $cb->($handle)
333
334When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
335set, then it will be invoked after freeing the TLS session. If it is not,
336then a TLS shutdown condition will be treated like a normal EOF condition
337on the handle.
338
339The session in C<< $handle->{tls} >> can still be examined in this
340callback.
341
342This callback will only be called on TLS shutdowns, not when the
343underlying handle signals EOF.
344
345=item json => JSON or JSON::XS object
346
347This is the json coder object used by the C<json> read and write types.
348
349If you don't supply it, then AnyEvent::Handle will create and use a
350suitable one (on demand), which will write and expect UTF-8 encoded JSON
351texts.
352
353Note that you are responsible to depend on the JSON module if you want to
354use this functionality, as AnyEvent does not have a dependency itself.
355
164=back 356=back
165 357
166=cut 358=cut
167 359
168sub new { 360sub new {
169 my $class = shift; 361 my $class = shift;
170
171 my $self = bless { @_ }, $class; 362 my $self = bless { @_ }, $class;
172 363
173 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 364 $self->{fh} or Carp::croak "mandatory argument fh is missing";
174 365
175 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 366 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
176 367
177 if ($self->{tls}) { 368 $self->{_activity} = AnyEvent->now;
178 require Net::SSLeay; 369 $self->_timeout;
370
371 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
372
179 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 373 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
180 } 374 if $self->{tls};
181 375
182 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
183 $self->on_error (delete $self->{on_error}) if $self->{on_error};
184 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 376 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
185 $self->on_read (delete $self->{on_read} ) if $self->{on_read};
186 377
187 $self->start_read; 378 $self->start_read
379 if $self->{on_read};
188 380
189 $self 381 $self->{fh} && $self
190} 382}
191 383
192sub _shutdown { 384#sub _shutdown {
193 my ($self) = @_; 385# my ($self) = @_;
386#
387# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
388# $self->{_eof} = 1; # tell starttls et. al to stop trying
389#
390# &_freetls;
391#}
194 392
195 delete $self->{rw};
196 delete $self->{ww};
197 delete $self->{fh};
198}
199
200sub error { 393sub _error {
201 my ($self) = @_; 394 my ($self, $errno, $fatal, $message) = @_;
202 395
203 { 396 $! = $errno;
204 local $!; 397 $message ||= "$!";
205 $self->_shutdown;
206 }
207 398
208 if ($self->{on_error}) { 399 if ($self->{on_error}) {
209 $self->{on_error}($self); 400 $self->{on_error}($self, $fatal, $message);
210 } else { 401 $self->destroy if $fatal;
402 } elsif ($self->{fh}) {
403 $self->destroy;
211 die "AnyEvent::Handle uncaught fatal error: $!"; 404 Carp::croak "AnyEvent::Handle uncaught error: $message";
212 } 405 }
213} 406}
214 407
215=item $fh = $handle->fh 408=item $fh = $handle->fh
216 409
217This method returns the filehandle of the L<AnyEvent::Handle> object. 410This method returns the file handle used to create the L<AnyEvent::Handle> object.
218 411
219=cut 412=cut
220 413
221sub fh { $_[0]->{fh} } 414sub fh { $_[0]{fh} }
222 415
223=item $handle->on_error ($cb) 416=item $handle->on_error ($cb)
224 417
225Replace the current C<on_error> callback (see the C<on_error> constructor argument). 418Replace the current C<on_error> callback (see the C<on_error> constructor argument).
226 419
238 431
239sub on_eof { 432sub on_eof {
240 $_[0]{on_eof} = $_[1]; 433 $_[0]{on_eof} = $_[1];
241} 434}
242 435
436=item $handle->on_timeout ($cb)
437
438Replace the current C<on_timeout> callback, or disables the callback (but
439not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
440argument and method.
441
442=cut
443
444sub on_timeout {
445 $_[0]{on_timeout} = $_[1];
446}
447
448=item $handle->autocork ($boolean)
449
450Enables or disables the current autocork behaviour (see C<autocork>
451constructor argument). Changes will only take effect on the next write.
452
453=cut
454
455sub autocork {
456 $_[0]{autocork} = $_[1];
457}
458
459=item $handle->no_delay ($boolean)
460
461Enables or disables the C<no_delay> setting (see constructor argument of
462the same name for details).
463
464=cut
465
466sub no_delay {
467 $_[0]{no_delay} = $_[1];
468
469 eval {
470 local $SIG{__DIE__};
471 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
472 };
473}
474
475=item $handle->on_starttls ($cb)
476
477Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
478
479=cut
480
481sub on_starttls {
482 $_[0]{on_starttls} = $_[1];
483}
484
485=item $handle->on_stoptls ($cb)
486
487Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
488
489=cut
490
491sub on_starttls {
492 $_[0]{on_stoptls} = $_[1];
493}
494
495#############################################################################
496
497=item $handle->timeout ($seconds)
498
499Configures (or disables) the inactivity timeout.
500
501=cut
502
503sub timeout {
504 my ($self, $timeout) = @_;
505
506 $self->{timeout} = $timeout;
507 $self->_timeout;
508}
509
510# reset the timeout watcher, as neccessary
511# also check for time-outs
512sub _timeout {
513 my ($self) = @_;
514
515 if ($self->{timeout}) {
516 my $NOW = AnyEvent->now;
517
518 # when would the timeout trigger?
519 my $after = $self->{_activity} + $self->{timeout} - $NOW;
520
521 # now or in the past already?
522 if ($after <= 0) {
523 $self->{_activity} = $NOW;
524
525 if ($self->{on_timeout}) {
526 $self->{on_timeout}($self);
527 } else {
528 $self->_error (Errno::ETIMEDOUT);
529 }
530
531 # callback could have changed timeout value, optimise
532 return unless $self->{timeout};
533
534 # calculate new after
535 $after = $self->{timeout};
536 }
537
538 Scalar::Util::weaken $self;
539 return unless $self; # ->error could have destroyed $self
540
541 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
542 delete $self->{_tw};
543 $self->_timeout;
544 });
545 } else {
546 delete $self->{_tw};
547 }
548}
549
243############################################################################# 550#############################################################################
244 551
245=back 552=back
246 553
247=head2 WRITE QUEUE 554=head2 WRITE QUEUE
268 my ($self, $cb) = @_; 575 my ($self, $cb) = @_;
269 576
270 $self->{on_drain} = $cb; 577 $self->{on_drain} = $cb;
271 578
272 $cb->($self) 579 $cb->($self)
273 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 580 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
274} 581}
275 582
276=item $handle->push_write ($data) 583=item $handle->push_write ($data)
277 584
278Queues the given scalar to be written. You can push as much data as you 585Queues the given scalar to be written. You can push as much data as you
282=cut 589=cut
283 590
284sub _drain_wbuf { 591sub _drain_wbuf {
285 my ($self) = @_; 592 my ($self) = @_;
286 593
287 unless ($self->{ww}) { 594 if (!$self->{_ww} && length $self->{wbuf}) {
595
288 Scalar::Util::weaken $self; 596 Scalar::Util::weaken $self;
597
289 my $cb = sub { 598 my $cb = sub {
290 my $len = syswrite $self->{fh}, $self->{wbuf}; 599 my $len = syswrite $self->{fh}, $self->{wbuf};
291 600
292 if ($len > 0) { 601 if (defined $len) {
293 substr $self->{wbuf}, 0, $len, ""; 602 substr $self->{wbuf}, 0, $len, "";
294 603
604 $self->{_activity} = AnyEvent->now;
605
295 $self->{on_drain}($self) 606 $self->{on_drain}($self)
296 if $self->{low_water_mark} >= length $self->{wbuf} 607 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
297 && $self->{on_drain}; 608 && $self->{on_drain};
298 609
299 delete $self->{ww} unless length $self->{wbuf}; 610 delete $self->{_ww} unless length $self->{wbuf};
300 } elsif ($! != EAGAIN && $! != EINTR) { 611 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
301 $self->error; 612 $self->_error ($!, 1);
302 } 613 }
303 }; 614 };
304 615
616 # try to write data immediately
617 $cb->() unless $self->{autocork};
618
619 # if still data left in wbuf, we need to poll
305 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb); 620 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
306 621 if length $self->{wbuf};
307 $cb->($self);
308 }; 622 };
623}
624
625our %WH;
626
627sub register_write_type($$) {
628 $WH{$_[0]} = $_[1];
309} 629}
310 630
311sub push_write { 631sub push_write {
312 my $self = shift; 632 my $self = shift;
313 633
634 if (@_ > 1) {
635 my $type = shift;
636
637 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
638 ->($self, @_);
639 }
640
314 if ($self->{filter_w}) { 641 if ($self->{tls}) {
315 $self->{filter_w}->($self, \$_[0]); 642 $self->{_tls_wbuf} .= $_[0];
643
644 &_dotls ($self);
316 } else { 645 } else {
317 $self->{wbuf} .= $_[0]; 646 $self->{wbuf} .= $_[0];
318 $self->_drain_wbuf; 647 $self->_drain_wbuf;
319 } 648 }
320} 649}
321 650
651=item $handle->push_write (type => @args)
652
653Instead of formatting your data yourself, you can also let this module do
654the job by specifying a type and type-specific arguments.
655
656Predefined types are (if you have ideas for additional types, feel free to
657drop by and tell us):
658
659=over 4
660
661=item netstring => $string
662
663Formats the given value as netstring
664(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
665
666=cut
667
668register_write_type netstring => sub {
669 my ($self, $string) = @_;
670
671 (length $string) . ":$string,"
672};
673
674=item packstring => $format, $data
675
676An octet string prefixed with an encoded length. The encoding C<$format>
677uses the same format as a Perl C<pack> format, but must specify a single
678integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
679optional C<!>, C<< < >> or C<< > >> modifier).
680
681=cut
682
683register_write_type packstring => sub {
684 my ($self, $format, $string) = @_;
685
686 pack "$format/a*", $string
687};
688
689=item json => $array_or_hashref
690
691Encodes the given hash or array reference into a JSON object. Unless you
692provide your own JSON object, this means it will be encoded to JSON text
693in UTF-8.
694
695JSON objects (and arrays) are self-delimiting, so you can write JSON at
696one end of a handle and read them at the other end without using any
697additional framing.
698
699The generated JSON text is guaranteed not to contain any newlines: While
700this module doesn't need delimiters after or between JSON texts to be
701able to read them, many other languages depend on that.
702
703A simple RPC protocol that interoperates easily with others is to send
704JSON arrays (or objects, although arrays are usually the better choice as
705they mimic how function argument passing works) and a newline after each
706JSON text:
707
708 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
709 $handle->push_write ("\012");
710
711An AnyEvent::Handle receiver would simply use the C<json> read type and
712rely on the fact that the newline will be skipped as leading whitespace:
713
714 $handle->push_read (json => sub { my $array = $_[1]; ... });
715
716Other languages could read single lines terminated by a newline and pass
717this line into their JSON decoder of choice.
718
719=cut
720
721register_write_type json => sub {
722 my ($self, $ref) = @_;
723
724 require JSON;
725
726 $self->{json} ? $self->{json}->encode ($ref)
727 : JSON::encode_json ($ref)
728};
729
730=item storable => $reference
731
732Freezes the given reference using L<Storable> and writes it to the
733handle. Uses the C<nfreeze> format.
734
735=cut
736
737register_write_type storable => sub {
738 my ($self, $ref) = @_;
739
740 require Storable;
741
742 pack "w/a*", Storable::nfreeze ($ref)
743};
744
745=back
746
747=item $handle->push_shutdown
748
749Sometimes you know you want to close the socket after writing your data
750before it was actually written. One way to do that is to replace your
751C<on_drain> handler by a callback that shuts down the socket (and set
752C<low_water_mark> to C<0>). This method is a shorthand for just that, and
753replaces the C<on_drain> callback with:
754
755 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown
756
757This simply shuts down the write side and signals an EOF condition to the
758the peer.
759
760You can rely on the normal read queue and C<on_eof> handling
761afterwards. This is the cleanest way to close a connection.
762
763=cut
764
765sub push_shutdown {
766 my ($self) = @_;
767
768 delete $self->{low_water_mark};
769 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
770}
771
772=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
773
774This function (not method) lets you add your own types to C<push_write>.
775Whenever the given C<type> is used, C<push_write> will invoke the code
776reference with the handle object and the remaining arguments.
777
778The code reference is supposed to return a single octet string that will
779be appended to the write buffer.
780
781Note that this is a function, and all types registered this way will be
782global, so try to use unique names.
783
784=cut
785
322############################################################################# 786#############################################################################
323 787
324=back 788=back
325 789
326=head2 READ QUEUE 790=head2 READ QUEUE
332ways, the "simple" way, using only C<on_read> and the "complex" way, using 796ways, the "simple" way, using only C<on_read> and the "complex" way, using
333a queue. 797a queue.
334 798
335In the simple case, you just install an C<on_read> callback and whenever 799In the simple case, you just install an C<on_read> callback and whenever
336new data arrives, it will be called. You can then remove some data (if 800new data arrives, it will be called. You can then remove some data (if
337enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 801enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
338or not. 802leave the data there if you want to accumulate more (e.g. when only a
803partial message has been received so far).
339 804
340In the more complex case, you want to queue multiple callbacks. In this 805In the more complex case, you want to queue multiple callbacks. In this
341case, AnyEvent::Handle will call the first queued callback each time new 806case, AnyEvent::Handle will call the first queued callback each time new
342data arrives and removes it when it has done its job (see C<push_read>, 807data arrives (also the first time it is queued) and removes it when it has
343below). 808done its job (see C<push_read>, below).
344 809
345This way you can, for example, push three line-reads, followed by reading 810This way you can, for example, push three line-reads, followed by reading
346a chunk of data, and AnyEvent::Handle will execute them in order. 811a chunk of data, and AnyEvent::Handle will execute them in order.
347 812
348Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 813Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
349the specified number of bytes which give an XML datagram. 814the specified number of bytes which give an XML datagram.
350 815
351 # in the default state, expect some header bytes 816 # in the default state, expect some header bytes
352 $handle->on_read (sub { 817 $handle->on_read (sub {
353 # some data is here, now queue the length-header-read (4 octets) 818 # some data is here, now queue the length-header-read (4 octets)
354 shift->unshift_read_chunk (4, sub { 819 shift->unshift_read (chunk => 4, sub {
355 # header arrived, decode 820 # header arrived, decode
356 my $len = unpack "N", $_[1]; 821 my $len = unpack "N", $_[1];
357 822
358 # now read the payload 823 # now read the payload
359 shift->unshift_read_chunk ($len, sub { 824 shift->unshift_read (chunk => $len, sub {
360 my $xml = $_[1]; 825 my $xml = $_[1];
361 # handle xml 826 # handle xml
362 }); 827 });
363 }); 828 });
364 }); 829 });
365 830
366Example 2: Implement a client for a protocol that replies either with 831Example 2: Implement a client for a protocol that replies either with "OK"
367"OK" and another line or "ERROR" for one request, and 64 bytes for the 832and another line or "ERROR" for the first request that is sent, and 64
368second request. Due tot he availability of a full queue, we can just 833bytes for the second request. Due to the availability of a queue, we can
369pipeline sending both requests and manipulate the queue as necessary in 834just pipeline sending both requests and manipulate the queue as necessary
370the callbacks: 835in the callbacks.
371 836
372 # request one 837When the first callback is called and sees an "OK" response, it will
838C<unshift> another line-read. This line-read will be queued I<before> the
83964-byte chunk callback.
840
841 # request one, returns either "OK + extra line" or "ERROR"
373 $handle->push_write ("request 1\015\012"); 842 $handle->push_write ("request 1\015\012");
374 843
375 # we expect "ERROR" or "OK" as response, so push a line read 844 # we expect "ERROR" or "OK" as response, so push a line read
376 $handle->push_read_line (sub { 845 $handle->push_read (line => sub {
377 # if we got an "OK", we have to _prepend_ another line, 846 # if we got an "OK", we have to _prepend_ another line,
378 # so it will be read before the second request reads its 64 bytes 847 # so it will be read before the second request reads its 64 bytes
379 # which are already in the queue when this callback is called 848 # which are already in the queue when this callback is called
380 # we don't do this in case we got an error 849 # we don't do this in case we got an error
381 if ($_[1] eq "OK") { 850 if ($_[1] eq "OK") {
382 $_[0]->unshift_read_line (sub { 851 $_[0]->unshift_read (line => sub {
383 my $response = $_[1]; 852 my $response = $_[1];
384 ... 853 ...
385 }); 854 });
386 } 855 }
387 }); 856 });
388 857
389 # request two 858 # request two, simply returns 64 octets
390 $handle->push_write ("request 2\015\012"); 859 $handle->push_write ("request 2\015\012");
391 860
392 # simply read 64 bytes, always 861 # simply read 64 bytes, always
393 $handle->push_read_chunk (64, sub { 862 $handle->push_read (chunk => 64, sub {
394 my $response = $_[1]; 863 my $response = $_[1];
395 ... 864 ...
396 }); 865 });
397 866
398=over 4 867=over 4
399 868
400=cut 869=cut
401 870
402sub _drain_rbuf { 871sub _drain_rbuf {
403 my ($self) = @_; 872 my ($self) = @_;
873
874 local $self->{_in_drain} = 1;
404 875
405 if ( 876 if (
406 defined $self->{rbuf_max} 877 defined $self->{rbuf_max}
407 && $self->{rbuf_max} < length $self->{rbuf} 878 && $self->{rbuf_max} < length $self->{rbuf}
408 ) { 879 ) {
409 $! = &Errno::ENOSPC; return $self->error; 880 $self->_error (Errno::ENOSPC, 1), return;
410 } 881 }
411 882
412 return if $self->{in_drain}; 883 while () {
413 local $self->{in_drain} = 1; 884 # we need to use a separate tls read buffer, as we must not receive data while
885 # we are draining the buffer, and this can only happen with TLS.
886 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
414 887
415 while (my $len = length $self->{rbuf}) { 888 my $len = length $self->{rbuf};
416 no strict 'refs'; 889
417 if (my $cb = shift @{ $self->{queue} }) { 890 if (my $cb = shift @{ $self->{_queue} }) {
418 if (!$cb->($self)) { 891 unless ($cb->($self)) {
419 if ($self->{eof}) { 892 if ($self->{_eof}) {
420 # no progress can be made (not enough data and no data forthcoming) 893 # no progress can be made (not enough data and no data forthcoming)
421 $! = &Errno::EPIPE; return $self->error; 894 $self->_error (Errno::EPIPE, 1), return;
422 } 895 }
423 896
424 unshift @{ $self->{queue} }, $cb; 897 unshift @{ $self->{_queue} }, $cb;
425 return; 898 last;
426 } 899 }
427 } elsif ($self->{on_read}) { 900 } elsif ($self->{on_read}) {
901 last unless $len;
902
428 $self->{on_read}($self); 903 $self->{on_read}($self);
429 904
430 if ( 905 if (
431 $self->{eof} # if no further data will arrive
432 && $len == length $self->{rbuf} # and no data has been consumed 906 $len == length $self->{rbuf} # if no data has been consumed
433 && !@{ $self->{queue} } # and the queue is still empty 907 && !@{ $self->{_queue} } # and the queue is still empty
434 && $self->{on_read} # and we still want to read data 908 && $self->{on_read} # but we still have on_read
435 ) { 909 ) {
910 # no further data will arrive
436 # then no progress can be made 911 # so no progress can be made
437 $! = &Errno::EPIPE; return $self->error; 912 $self->_error (Errno::EPIPE, 1), return
913 if $self->{_eof};
914
915 last; # more data might arrive
438 } 916 }
439 } else { 917 } else {
440 # read side becomes idle 918 # read side becomes idle
441 delete $self->{rw}; 919 delete $self->{_rw} unless $self->{tls};
442 return; 920 last;
443 } 921 }
444 } 922 }
445 923
446 if ($self->{eof}) { 924 if ($self->{_eof}) {
447 $self->_shutdown; 925 if ($self->{on_eof}) {
448 $self->{on_eof}($self) 926 $self->{on_eof}($self)
449 if $self->{on_eof}; 927 } else {
928 $self->_error (0, 1, "Unexpected end-of-file");
929 }
930 }
931
932 # may need to restart read watcher
933 unless ($self->{_rw}) {
934 $self->start_read
935 if $self->{on_read} || @{ $self->{_queue} };
450 } 936 }
451} 937}
452 938
453=item $handle->on_read ($cb) 939=item $handle->on_read ($cb)
454 940
460 946
461sub on_read { 947sub on_read {
462 my ($self, $cb) = @_; 948 my ($self, $cb) = @_;
463 949
464 $self->{on_read} = $cb; 950 $self->{on_read} = $cb;
951 $self->_drain_rbuf if $cb && !$self->{_in_drain};
465} 952}
466 953
467=item $handle->rbuf 954=item $handle->rbuf
468 955
469Returns the read buffer (as a modifiable lvalue). 956Returns the read buffer (as a modifiable lvalue).
470 957
471You can access the read buffer directly as the C<< ->{rbuf} >> member, if 958You can access the read buffer directly as the C<< ->{rbuf} >>
472you want. 959member, if you want. However, the only operation allowed on the
960read buffer (apart from looking at it) is removing data from its
961beginning. Otherwise modifying or appending to it is not allowed and will
962lead to hard-to-track-down bugs.
473 963
474NOTE: The read buffer should only be used or modified if the C<on_read>, 964NOTE: The read buffer should only be used or modified if the C<on_read>,
475C<push_read> or C<unshift_read> methods are used. The other read methods 965C<push_read> or C<unshift_read> methods are used. The other read methods
476automatically manage the read buffer. 966automatically manage the read buffer.
477 967
500interested in (which can be none at all) and return a true value. After returning 990interested in (which can be none at all) and return a true value. After returning
501true, it will be removed from the queue. 991true, it will be removed from the queue.
502 992
503=cut 993=cut
504 994
995our %RH;
996
997sub register_read_type($$) {
998 $RH{$_[0]} = $_[1];
999}
1000
505sub push_read { 1001sub push_read {
506 my ($self, $cb) = @_; 1002 my $self = shift;
1003 my $cb = pop;
507 1004
1005 if (@_) {
1006 my $type = shift;
1007
1008 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
1009 ->($self, $cb, @_);
1010 }
1011
508 push @{ $self->{queue} }, $cb; 1012 push @{ $self->{_queue} }, $cb;
509 $self->_drain_rbuf; 1013 $self->_drain_rbuf unless $self->{_in_drain};
510} 1014}
511 1015
512sub unshift_read { 1016sub unshift_read {
513 my ($self, $cb) = @_; 1017 my $self = shift;
1018 my $cb = pop;
514 1019
1020 if (@_) {
1021 my $type = shift;
1022
1023 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
1024 ->($self, $cb, @_);
1025 }
1026
1027
515 push @{ $self->{queue} }, $cb; 1028 unshift @{ $self->{_queue} }, $cb;
516 $self->_drain_rbuf; 1029 $self->_drain_rbuf unless $self->{_in_drain};
517} 1030}
518 1031
519=item $handle->push_read_chunk ($len, $cb->($self, $data)) 1032=item $handle->push_read (type => @args, $cb)
520 1033
521=item $handle->unshift_read_chunk ($len, $cb->($self, $data)) 1034=item $handle->unshift_read (type => @args, $cb)
522 1035
523Append the given callback to the end of the queue (C<push_read_chunk>) or 1036Instead of providing a callback that parses the data itself you can chose
524prepend it (C<unshift_read_chunk>). 1037between a number of predefined parsing formats, for chunks of data, lines
1038etc.
525 1039
526The callback will be called only once C<$len> bytes have been read, and 1040Predefined types are (if you have ideas for additional types, feel free to
527these C<$len> bytes will be passed to the callback. 1041drop by and tell us):
528 1042
529=cut 1043=over 4
530 1044
531sub _read_chunk($$) { 1045=item chunk => $octets, $cb->($handle, $data)
1046
1047Invoke the callback only once C<$octets> bytes have been read. Pass the
1048data read to the callback. The callback will never be called with less
1049data.
1050
1051Example: read 2 bytes.
1052
1053 $handle->push_read (chunk => 2, sub {
1054 warn "yay ", unpack "H*", $_[1];
1055 });
1056
1057=cut
1058
1059register_read_type chunk => sub {
532 my ($self, $len, $cb) = @_; 1060 my ($self, $cb, $len) = @_;
533 1061
534 sub { 1062 sub {
535 $len <= length $_[0]{rbuf} or return; 1063 $len <= length $_[0]{rbuf} or return;
536 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 1064 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
537 1 1065 1
538 } 1066 }
539} 1067};
540 1068
541sub push_read_chunk { 1069=item line => [$eol, ]$cb->($handle, $line, $eol)
542 $_[0]->push_read (&_read_chunk);
543}
544
545
546sub unshift_read_chunk {
547 $_[0]->unshift_read (&_read_chunk);
548}
549
550=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
551
552=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
553
554Append the given callback to the end of the queue (C<push_read_line>) or
555prepend it (C<unshift_read_line>).
556 1070
557The callback will be called only once a full line (including the end of 1071The callback will be called only once a full line (including the end of
558line marker, C<$eol>) has been read. This line (excluding the end of line 1072line marker, C<$eol>) has been read. This line (excluding the end of line
559marker) will be passed to the callback as second argument (C<$line>), and 1073marker) will be passed to the callback as second argument (C<$line>), and
560the end of line marker as the third argument (C<$eol>). 1074the end of line marker as the third argument (C<$eol>).
571Partial lines at the end of the stream will never be returned, as they are 1085Partial lines at the end of the stream will never be returned, as they are
572not marked by the end of line marker. 1086not marked by the end of line marker.
573 1087
574=cut 1088=cut
575 1089
576sub _read_line($$) { 1090register_read_type line => sub {
577 my $self = shift; 1091 my ($self, $cb, $eol) = @_;
578 my $cb = pop;
579 my $eol = @_ ? shift : qr|(\015?\012)|;
580 my $pos;
581 1092
1093 if (@_ < 3) {
1094 # this is more than twice as fast as the generic code below
1095 sub {
1096 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1097
1098 $cb->($_[0], $1, $2);
1099 1
1100 }
1101 } else {
582 $eol = quotemeta $eol unless ref $eol; 1102 $eol = quotemeta $eol unless ref $eol;
583 $eol = qr|^(.*?)($eol)|s; 1103 $eol = qr|^(.*?)($eol)|s;
1104
1105 sub {
1106 $_[0]{rbuf} =~ s/$eol// or return;
1107
1108 $cb->($_[0], $1, $2);
1109 1
1110 }
1111 }
1112};
1113
1114=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
1115
1116Makes a regex match against the regex object C<$accept> and returns
1117everything up to and including the match.
1118
1119Example: read a single line terminated by '\n'.
1120
1121 $handle->push_read (regex => qr<\n>, sub { ... });
1122
1123If C<$reject> is given and not undef, then it determines when the data is
1124to be rejected: it is matched against the data when the C<$accept> regex
1125does not match and generates an C<EBADMSG> error when it matches. This is
1126useful to quickly reject wrong data (to avoid waiting for a timeout or a
1127receive buffer overflow).
1128
1129Example: expect a single decimal number followed by whitespace, reject
1130anything else (not the use of an anchor).
1131
1132 $handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
1133
1134If C<$skip> is given and not C<undef>, then it will be matched against
1135the receive buffer when neither C<$accept> nor C<$reject> match,
1136and everything preceding and including the match will be accepted
1137unconditionally. This is useful to skip large amounts of data that you
1138know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1139have to start matching from the beginning. This is purely an optimisation
1140and is usually worth only when you expect more than a few kilobytes.
1141
1142Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1143expect the header to be very large (it isn't in practise, but...), we use
1144a skip regex to skip initial portions. The skip regex is tricky in that
1145it only accepts something not ending in either \015 or \012, as these are
1146required for the accept regex.
1147
1148 $handle->push_read (regex =>
1149 qr<\015\012\015\012>,
1150 undef, # no reject
1151 qr<^.*[^\015\012]>,
1152 sub { ... });
1153
1154=cut
1155
1156register_read_type regex => sub {
1157 my ($self, $cb, $accept, $reject, $skip) = @_;
1158
1159 my $data;
1160 my $rbuf = \$self->{rbuf};
584 1161
585 sub { 1162 sub {
586 $_[0]{rbuf} =~ s/$eol// or return; 1163 # accept
1164 if ($$rbuf =~ $accept) {
1165 $data .= substr $$rbuf, 0, $+[0], "";
1166 $cb->($self, $data);
1167 return 1;
1168 }
1169
1170 # reject
1171 if ($reject && $$rbuf =~ $reject) {
1172 $self->_error (Errno::EBADMSG);
1173 }
587 1174
588 $cb->($_[0], $1, $2); 1175 # skip
1176 if ($skip && $$rbuf =~ $skip) {
1177 $data .= substr $$rbuf, 0, $+[0], "";
1178 }
1179
1180 ()
1181 }
1182};
1183
1184=item netstring => $cb->($handle, $string)
1185
1186A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1187
1188Throws an error with C<$!> set to EBADMSG on format violations.
1189
1190=cut
1191
1192register_read_type netstring => sub {
1193 my ($self, $cb) = @_;
1194
1195 sub {
1196 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1197 if ($_[0]{rbuf} =~ /[^0-9]/) {
1198 $self->_error (Errno::EBADMSG);
1199 }
1200 return;
1201 }
1202
1203 my $len = $1;
1204
1205 $self->unshift_read (chunk => $len, sub {
1206 my $string = $_[1];
1207 $_[0]->unshift_read (chunk => 1, sub {
1208 if ($_[1] eq ",") {
1209 $cb->($_[0], $string);
1210 } else {
1211 $self->_error (Errno::EBADMSG);
1212 }
1213 });
1214 });
1215
589 1 1216 1
590 } 1217 }
591} 1218};
592 1219
593sub push_read_line { 1220=item packstring => $format, $cb->($handle, $string)
594 $_[0]->push_read (&_read_line);
595}
596 1221
597sub unshift_read_line { 1222An octet string prefixed with an encoded length. The encoding C<$format>
598 $_[0]->unshift_read (&_read_line); 1223uses the same format as a Perl C<pack> format, but must specify a single
599} 1224integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1225optional C<!>, C<< < >> or C<< > >> modifier).
1226
1227For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1228EPP uses a prefix of C<N> (4 octtes).
1229
1230Example: read a block of data prefixed by its length in BER-encoded
1231format (very efficient).
1232
1233 $handle->push_read (packstring => "w", sub {
1234 my ($handle, $data) = @_;
1235 });
1236
1237=cut
1238
1239register_read_type packstring => sub {
1240 my ($self, $cb, $format) = @_;
1241
1242 sub {
1243 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1244 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1245 or return;
1246
1247 $format = length pack $format, $len;
1248
1249 # bypass unshift if we already have the remaining chunk
1250 if ($format + $len <= length $_[0]{rbuf}) {
1251 my $data = substr $_[0]{rbuf}, $format, $len;
1252 substr $_[0]{rbuf}, 0, $format + $len, "";
1253 $cb->($_[0], $data);
1254 } else {
1255 # remove prefix
1256 substr $_[0]{rbuf}, 0, $format, "";
1257
1258 # read remaining chunk
1259 $_[0]->unshift_read (chunk => $len, $cb);
1260 }
1261
1262 1
1263 }
1264};
1265
1266=item json => $cb->($handle, $hash_or_arrayref)
1267
1268Reads a JSON object or array, decodes it and passes it to the
1269callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1270
1271If a C<json> object was passed to the constructor, then that will be used
1272for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1273
1274This read type uses the incremental parser available with JSON version
12752.09 (and JSON::XS version 2.2) and above. You have to provide a
1276dependency on your own: this module will load the JSON module, but
1277AnyEvent does not depend on it itself.
1278
1279Since JSON texts are fully self-delimiting, the C<json> read and write
1280types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1281the C<json> write type description, above, for an actual example.
1282
1283=cut
1284
1285register_read_type json => sub {
1286 my ($self, $cb) = @_;
1287
1288 my $json = $self->{json} ||=
1289 eval { require JSON::XS; JSON::XS->new->utf8 }
1290 || do { require JSON; JSON->new->utf8 };
1291
1292 my $data;
1293 my $rbuf = \$self->{rbuf};
1294
1295 sub {
1296 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1297
1298 if ($ref) {
1299 $self->{rbuf} = $json->incr_text;
1300 $json->incr_text = "";
1301 $cb->($self, $ref);
1302
1303 1
1304 } elsif ($@) {
1305 # error case
1306 $json->incr_skip;
1307
1308 $self->{rbuf} = $json->incr_text;
1309 $json->incr_text = "";
1310
1311 $self->_error (Errno::EBADMSG);
1312
1313 ()
1314 } else {
1315 $self->{rbuf} = "";
1316
1317 ()
1318 }
1319 }
1320};
1321
1322=item storable => $cb->($handle, $ref)
1323
1324Deserialises a L<Storable> frozen representation as written by the
1325C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1326data).
1327
1328Raises C<EBADMSG> error if the data could not be decoded.
1329
1330=cut
1331
1332register_read_type storable => sub {
1333 my ($self, $cb) = @_;
1334
1335 require Storable;
1336
1337 sub {
1338 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1339 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1340 or return;
1341
1342 my $format = length pack "w", $len;
1343
1344 # bypass unshift if we already have the remaining chunk
1345 if ($format + $len <= length $_[0]{rbuf}) {
1346 my $data = substr $_[0]{rbuf}, $format, $len;
1347 substr $_[0]{rbuf}, 0, $format + $len, "";
1348 $cb->($_[0], Storable::thaw ($data));
1349 } else {
1350 # remove prefix
1351 substr $_[0]{rbuf}, 0, $format, "";
1352
1353 # read remaining chunk
1354 $_[0]->unshift_read (chunk => $len, sub {
1355 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1356 $cb->($_[0], $ref);
1357 } else {
1358 $self->_error (Errno::EBADMSG);
1359 }
1360 });
1361 }
1362
1363 1
1364 }
1365};
1366
1367=back
1368
1369=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
1370
1371This function (not method) lets you add your own types to C<push_read>.
1372
1373Whenever the given C<type> is used, C<push_read> will invoke the code
1374reference with the handle object, the callback and the remaining
1375arguments.
1376
1377The code reference is supposed to return a callback (usually a closure)
1378that works as a plain read callback (see C<< ->push_read ($cb) >>).
1379
1380It should invoke the passed callback when it is done reading (remember to
1381pass C<$handle> as first argument as all other callbacks do that).
1382
1383Note that this is a function, and all types registered this way will be
1384global, so try to use unique names.
1385
1386For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
1387search for C<register_read_type>)).
600 1388
601=item $handle->stop_read 1389=item $handle->stop_read
602 1390
603=item $handle->start_read 1391=item $handle->start_read
604 1392
605In rare cases you actually do not want to read anything from the 1393In rare cases you actually do not want to read anything from the
606socket. In this case you can call C<stop_read>. Neither C<on_read> no 1394socket. In this case you can call C<stop_read>. Neither C<on_read> nor
607any queued callbacks will be executed then. To start readign again, call 1395any queued callbacks will be executed then. To start reading again, call
608C<start_read>. 1396C<start_read>.
1397
1398Note that AnyEvent::Handle will automatically C<start_read> for you when
1399you change the C<on_read> callback or push/unshift a read callback, and it
1400will automatically C<stop_read> for you when neither C<on_read> is set nor
1401there are any read requests in the queue.
1402
1403These methods will have no effect when in TLS mode (as TLS doesn't support
1404half-duplex connections).
609 1405
610=cut 1406=cut
611 1407
612sub stop_read { 1408sub stop_read {
613 my ($self) = @_; 1409 my ($self) = @_;
614 1410
615 delete $self->{rw}; 1411 delete $self->{_rw} unless $self->{tls};
616} 1412}
617 1413
618sub start_read { 1414sub start_read {
619 my ($self) = @_; 1415 my ($self) = @_;
620 1416
621 unless ($self->{rw} || $self->{eof}) { 1417 unless ($self->{_rw} || $self->{_eof}) {
622 Scalar::Util::weaken $self; 1418 Scalar::Util::weaken $self;
623 1419
624 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1420 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
625 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1421 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
626 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1422 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
627 1423
628 if ($len > 0) { 1424 if ($len > 0) {
629 $self->{filter_r} 1425 $self->{_activity} = AnyEvent->now;
630 ? $self->{filter_r}->($self, $rbuf) 1426
631 : $self->_drain_rbuf; 1427 if ($self->{tls}) {
1428 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1429
1430 &_dotls ($self);
1431 } else {
1432 $self->_drain_rbuf unless $self->{_in_drain};
1433 }
632 1434
633 } elsif (defined $len) { 1435 } elsif (defined $len) {
634 delete $self->{rw}; 1436 delete $self->{_rw};
635 $self->{eof} = 1; 1437 $self->{_eof} = 1;
636 $self->_drain_rbuf; 1438 $self->_drain_rbuf unless $self->{_in_drain};
637 1439
638 } elsif ($! != EAGAIN && $! != EINTR) { 1440 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
639 return $self->error; 1441 return $self->_error ($!, 1);
640 } 1442 }
641 }); 1443 });
642 } 1444 }
643} 1445}
644 1446
1447our $ERROR_SYSCALL;
1448our $ERROR_WANT_READ;
1449
1450sub _tls_error {
1451 my ($self, $err) = @_;
1452
1453 return $self->_error ($!, 1)
1454 if $err == Net::SSLeay::ERROR_SYSCALL ();
1455
1456 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1457
1458 # reduce error string to look less scary
1459 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1460
1461 if ($self->{_on_starttls}) {
1462 (delete $self->{_on_starttls})->($self, undef, $err);
1463 &_freetls;
1464 } else {
1465 &_freetls;
1466 $self->_error (Errno::EPROTO, 1, $err);
1467 }
1468}
1469
1470# poll the write BIO and send the data if applicable
1471# also decode read data if possible
1472# this is basiclaly our TLS state machine
1473# more efficient implementations are possible with openssl,
1474# but not with the buggy and incomplete Net::SSLeay.
645sub _dotls { 1475sub _dotls {
646 my ($self) = @_; 1476 my ($self) = @_;
647 1477
1478 my $tmp;
1479
648 if (length $self->{tls_wbuf}) { 1480 if (length $self->{_tls_wbuf}) {
649 my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf}); 1481 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
650 substr $self->{tls_wbuf}, 0, $len, "" if $len > 0; 1482 substr $self->{_tls_wbuf}, 0, $tmp, "";
651 } 1483 }
652 1484
1485 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1486 return $self->_tls_error ($tmp)
1487 if $tmp != $ERROR_WANT_READ
1488 && ($tmp != $ERROR_SYSCALL || $!);
1489 }
1490
653 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) { 1491 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1492 unless (length $tmp) {
1493 $self->{_on_starttls}
1494 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1495 &_freetls;
1496
1497 if ($self->{on_stoptls}) {
1498 $self->{on_stoptls}($self);
1499 return;
1500 } else {
1501 # let's treat SSL-eof as we treat normal EOF
1502 delete $self->{_rw};
1503 $self->{_eof} = 1;
1504 }
1505 }
1506
1507 $self->{_tls_rbuf} .= $tmp;
1508 $self->_drain_rbuf unless $self->{_in_drain};
1509 $self->{tls} or return; # tls session might have gone away in callback
1510 }
1511
1512 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1513 return $self->_tls_error ($tmp)
1514 if $tmp != $ERROR_WANT_READ
1515 && ($tmp != $ERROR_SYSCALL || $!);
1516
1517 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
654 $self->{wbuf} .= $buf; 1518 $self->{wbuf} .= $tmp;
655 $self->_drain_wbuf; 1519 $self->_drain_wbuf;
656 } 1520 }
657 1521
658 if (defined (my $buf = Net::SSLeay::read ($self->{tls}))) { 1522 $self->{_on_starttls}
659 $self->{rbuf} .= $buf; 1523 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
660 $self->_drain_rbuf; 1524 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
661 } elsif (
662 (my $err = Net::SSLeay::get_error ($self->{tls}, -1))
663 != Net::SSLeay::ERROR_WANT_READ ()
664 ) {
665 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
666 $self->error;
667 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
668 $! = &Errno::EIO;
669 $self->error;
670 }
671
672 # all others are fine for our purposes
673 }
674} 1525}
675 1526
676# TODO: maybe document... 1527=item $handle->starttls ($tls[, $tls_ctx])
1528
1529Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1530object is created, you can also do that at a later time by calling
1531C<starttls>.
1532
1533Starting TLS is currently an asynchronous operation - when you push some
1534write data and then call C<< ->starttls >> then TLS negotiation will start
1535immediately, after which the queued write data is then sent.
1536
1537The first argument is the same as the C<tls> constructor argument (either
1538C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1539
1540The second argument is the optional C<AnyEvent::TLS> object that is used
1541when AnyEvent::Handle has to create its own TLS connection object, or
1542a hash reference with C<< key => value >> pairs that will be used to
1543construct a new context.
1544
1545The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1546context in C<< $handle->{tls_ctx} >> after this call and can be used or
1547changed to your liking. Note that the handshake might have already started
1548when this function returns.
1549
1550If it an error to start a TLS handshake more than once per
1551AnyEvent::Handle object (this is due to bugs in OpenSSL).
1552
1553=cut
1554
1555our %TLS_CACHE; #TODO not yet documented, should we?
1556
677sub starttls { 1557sub starttls {
678 my ($self, $ssl, $ctx) = @_; 1558 my ($self, $ssl, $ctx) = @_;
679 1559
680 if ($ssl eq "accept") { 1560 require Net::SSLeay;
681 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1561
682 Net::SSLeay::set_accept_state ($ssl); 1562 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
683 } elsif ($ssl eq "connect") { 1563 if $self->{tls};
684 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1564
685 Net::SSLeay::set_connect_state ($ssl); 1565 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1566 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1567
1568 $ctx ||= $self->{tls_ctx};
1569
1570 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1571
1572 if ("HASH" eq ref $ctx) {
1573 require AnyEvent::TLS;
1574
1575 if ($ctx->{cache}) {
1576 my $key = $ctx+0;
1577 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1578 } else {
1579 $ctx = new AnyEvent::TLS %$ctx;
1580 }
1581 }
686 } 1582
1583 $self->{tls_ctx} = $ctx || TLS_CTX ();
1584 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername});
687 1585
688 $self->{tls} = $ssl; 1586 # basically, this is deep magic (because SSL_read should have the same issues)
1587 # but the openssl maintainers basically said: "trust us, it just works".
1588 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1589 # and mismaintained ssleay-module doesn't even offer them).
1590 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1591 #
1592 # in short: this is a mess.
1593 #
1594 # note that we do not try to keep the length constant between writes as we are required to do.
1595 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1596 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1597 # have identity issues in that area.
1598# Net::SSLeay::CTX_set_mode ($ssl,
1599# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1600# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1601 Net::SSLeay::CTX_set_mode ($ssl, 1|2);
689 1602
690 $self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1603 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
691 $self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1604 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
692 1605
693 Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio}); 1606 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
694 1607
695 $self->{filter_w} = sub { 1608 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
696 $_[0]{tls_wbuf} .= ${$_[1]}; 1609 if $self->{on_starttls};
1610
1611 &_dotls; # need to trigger the initial handshake
1612 $self->start_read; # make sure we actually do read
1613}
1614
1615=item $handle->stoptls
1616
1617Shuts down the SSL connection - this makes a proper EOF handshake by
1618sending a close notify to the other side, but since OpenSSL doesn't
1619support non-blocking shut downs, it is not possible to re-use the stream
1620afterwards.
1621
1622=cut
1623
1624sub stoptls {
1625 my ($self) = @_;
1626
1627 if ($self->{tls}) {
1628 Net::SSLeay::shutdown ($self->{tls});
1629
697 &_dotls; 1630 &_dotls;
1631
1632# # we don't give a shit. no, we do, but we can't. no...#d#
1633# # we, we... have to use openssl :/#d#
1634# &_freetls;#d#
1635 }
1636}
1637
1638sub _freetls {
1639 my ($self) = @_;
1640
1641 return unless $self->{tls};
1642
1643 $self->{tls_ctx}->_put_session (delete $self->{tls});
1644
1645 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1646}
1647
1648sub DESTROY {
1649 my ($self) = @_;
1650
1651 &_freetls;
1652
1653 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1654
1655 if ($linger && length $self->{wbuf} && $self->{fh}) {
1656 my $fh = delete $self->{fh};
1657 my $wbuf = delete $self->{wbuf};
1658
1659 my @linger;
1660
1661 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1662 my $len = syswrite $fh, $wbuf, length $wbuf;
1663
1664 if ($len > 0) {
1665 substr $wbuf, 0, $len, "";
1666 } else {
1667 @linger = (); # end
1668 }
1669 });
1670 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1671 @linger = ();
1672 });
1673 }
1674}
1675
1676=item $handle->destroy
1677
1678Shuts down the handle object as much as possible - this call ensures that
1679no further callbacks will be invoked and as many resources as possible
1680will be freed. You must not call any methods on the object afterwards.
1681
1682Normally, you can just "forget" any references to an AnyEvent::Handle
1683object and it will simply shut down. This works in fatal error and EOF
1684callbacks, as well as code outside. It does I<NOT> work in a read or write
1685callback, so when you want to destroy the AnyEvent::Handle object from
1686within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1687that case.
1688
1689Destroying the handle object in this way has the advantage that callbacks
1690will be removed as well, so if those are the only reference holders (as
1691is common), then one doesn't need to do anything special to break any
1692reference cycles.
1693
1694The handle might still linger in the background and write out remaining
1695data, as specified by the C<linger> option, however.
1696
1697=cut
1698
1699sub destroy {
1700 my ($self) = @_;
1701
1702 $self->DESTROY;
1703 %$self = ();
1704}
1705
1706=item AnyEvent::Handle::TLS_CTX
1707
1708This function creates and returns the AnyEvent::TLS object used by default
1709for TLS mode.
1710
1711The context is created by calling L<AnyEvent::TLS> without any arguments.
1712
1713=cut
1714
1715our $TLS_CTX;
1716
1717sub TLS_CTX() {
1718 $TLS_CTX ||= do {
1719 require AnyEvent::TLS;
1720
1721 new AnyEvent::TLS
1722 }
1723}
1724
1725=back
1726
1727
1728=head1 NONFREQUENTLY ASKED QUESTIONS
1729
1730=over 4
1731
1732=item I C<undef> the AnyEvent::Handle reference inside my callback and
1733still get further invocations!
1734
1735That's because AnyEvent::Handle keeps a reference to itself when handling
1736read or write callbacks.
1737
1738It is only safe to "forget" the reference inside EOF or error callbacks,
1739from within all other callbacks, you need to explicitly call the C<<
1740->destroy >> method.
1741
1742=item I get different callback invocations in TLS mode/Why can't I pause
1743reading?
1744
1745Unlike, say, TCP, TLS connections do not consist of two independent
1746communication channels, one for each direction. Or put differently. The
1747read and write directions are not independent of each other: you cannot
1748write data unless you are also prepared to read, and vice versa.
1749
1750This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1751callback invocations when you are not expecting any read data - the reason
1752is that AnyEvent::Handle always reads in TLS mode.
1753
1754During the connection, you have to make sure that you always have a
1755non-empty read-queue, or an C<on_read> watcher. At the end of the
1756connection (or when you no longer want to use it) you can call the
1757C<destroy> method.
1758
1759=item How do I read data until the other side closes the connection?
1760
1761If you just want to read your data into a perl scalar, the easiest way
1762to achieve this is by setting an C<on_read> callback that does nothing,
1763clearing the C<on_eof> callback and in the C<on_error> callback, the data
1764will be in C<$_[0]{rbuf}>:
1765
1766 $handle->on_read (sub { });
1767 $handle->on_eof (undef);
1768 $handle->on_error (sub {
1769 my $data = delete $_[0]{rbuf};
1770 });
1771
1772The reason to use C<on_error> is that TCP connections, due to latencies
1773and packets loss, might get closed quite violently with an error, when in
1774fact, all data has been received.
1775
1776It is usually better to use acknowledgements when transferring data,
1777to make sure the other side hasn't just died and you got the data
1778intact. This is also one reason why so many internet protocols have an
1779explicit QUIT command.
1780
1781=item I don't want to destroy the handle too early - how do I wait until
1782all data has been written?
1783
1784After writing your last bits of data, set the C<on_drain> callback
1785and destroy the handle in there - with the default setting of
1786C<low_water_mark> this will be called precisely when all data has been
1787written to the socket:
1788
1789 $handle->push_write (...);
1790 $handle->on_drain (sub {
1791 warn "all data submitted to the kernel\n";
1792 undef $handle;
1793 });
1794
1795If you just want to queue some data and then signal EOF to the other side,
1796consider using C<< ->push_shutdown >> instead.
1797
1798=item I want to contact a TLS/SSL server, I don't care about security.
1799
1800If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1801simply connect to it and then create the AnyEvent::Handle with the C<tls>
1802parameter:
1803
1804 tcp_connect $host, $port, sub {
1805 my ($fh) = @_;
1806
1807 my $handle = new AnyEvent::Handle
1808 fh => $fh,
1809 tls => "connect",
1810 on_error => sub { ... };
1811
1812 $handle->push_write (...);
698 }; 1813 };
699 $self->{filter_r} = sub {
700 Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
701 &_dotls;
702 };
703}
704 1814
705sub DESTROY { 1815=item I want to contact a TLS/SSL server, I do care about security.
706 my $self = shift;
707 1816
708 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1817Then you should additionally enable certificate verification, including
709} 1818peername verification, if the protocol you use supports it (see
1819L<AnyEvent::TLS>, C<verify_peername>).
710 1820
711=item AnyEvent::Handle::TLS_CTX 1821E.g. for HTTPS:
712 1822
713This function creates and returns the Net::SSLeay::CTX object used by 1823 tcp_connect $host, $port, sub {
714default for TLS mode. 1824 my ($fh) = @_;
715 1825
716The context is created like this: 1826 my $handle = new AnyEvent::Handle
1827 fh => $fh,
1828 peername => $host,
1829 tls => "connect",
1830 tls_ctx => { verify => 1, verify_peername => "https" },
1831 ...
717 1832
718 Net::SSLeay::load_error_strings; 1833Note that you must specify the hostname you connected to (or whatever
719 Net::SSLeay::SSLeay_add_ssl_algorithms; 1834"peername" the protocol needs) as the C<peername> argument, otherwise no
720 Net::SSLeay::randomize; 1835peername verification will be done.
721 1836
722 my $CTX = Net::SSLeay::CTX_new; 1837The above will use the system-dependent default set of trusted CA
1838certificates. If you want to check against a specific CA, add the
1839C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
723 1840
724 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL 1841 tls_ctx => {
1842 verify => 1,
1843 verify_peername => "https",
1844 ca_file => "my-ca-cert.pem",
1845 },
725 1846
726=cut 1847=item I want to create a TLS/SSL server, how do I do that?
727 1848
728our $TLS_CTX; 1849Well, you first need to get a server certificate and key. You have
1850three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
1851self-signed certificate (cheap. check the search engine of your choice,
1852there are many tutorials on the net) or c) make your own CA (tinyca2 is a
1853nice program for that purpose).
729 1854
730sub TLS_CTX() { 1855Then create a file with your private key (in PEM format, see
731 $TLS_CTX || do { 1856L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
732 require Net::SSLeay; 1857file should then look like this:
733 1858
734 Net::SSLeay::load_error_strings (); 1859 -----BEGIN RSA PRIVATE KEY-----
735 Net::SSLeay::SSLeay_add_ssl_algorithms (); 1860 ...header data
736 Net::SSLeay::randomize (); 1861 ... lots of base64'y-stuff
1862 -----END RSA PRIVATE KEY-----
737 1863
738 $TLS_CTX = Net::SSLeay::CTX_new (); 1864 -----BEGIN CERTIFICATE-----
1865 ... lots of base64'y-stuff
1866 -----END CERTIFICATE-----
739 1867
740 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ()); 1868The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
1869specify this file as C<cert_file>:
741 1870
742 $TLS_CTX 1871 tcp_server undef, $port, sub {
743 } 1872 my ($fh) = @_;
744} 1873
1874 my $handle = new AnyEvent::Handle
1875 fh => $fh,
1876 tls => "accept",
1877 tls_ctx => { cert_file => "my-server-keycert.pem" },
1878 ...
1879
1880When you have intermediate CA certificates that your clients might not
1881know about, just append them to the C<cert_file>.
745 1882
746=back 1883=back
747 1884
1885
1886=head1 SUBCLASSING AnyEvent::Handle
1887
1888In many cases, you might want to subclass AnyEvent::Handle.
1889
1890To make this easier, a given version of AnyEvent::Handle uses these
1891conventions:
1892
1893=over 4
1894
1895=item * all constructor arguments become object members.
1896
1897At least initially, when you pass a C<tls>-argument to the constructor it
1898will end up in C<< $handle->{tls} >>. Those members might be changed or
1899mutated later on (for example C<tls> will hold the TLS connection object).
1900
1901=item * other object member names are prefixed with an C<_>.
1902
1903All object members not explicitly documented (internal use) are prefixed
1904with an underscore character, so the remaining non-C<_>-namespace is free
1905for use for subclasses.
1906
1907=item * all members not documented here and not prefixed with an underscore
1908are free to use in subclasses.
1909
1910Of course, new versions of AnyEvent::Handle may introduce more "public"
1911member variables, but thats just life, at least it is documented.
1912
1913=back
1914
748=head1 AUTHOR 1915=head1 AUTHOR
749 1916
750Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 1917Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
751 1918
752=cut 1919=cut

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