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Revision 1.9 by root, Fri May 2 16:07:46 2008 UTC vs.
Revision 1.94 by root, Wed Oct 1 15:50:33 2008 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 (); 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 filehandles via AnyEvent 15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 16
17=cut 17=cut
18 18
19our $VERSION = '0.02'; 19our $VERSION = 4.3;
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 $ae_fh = AnyEvent::Handle->new (fh => \*STDIN); 28 my $handle =
29
30 #TODO
31
32 # or use the constructor to pass the callback:
33
34 my $ae_fh2 =
35 AnyEvent::Handle->new ( 29 AnyEvent::Handle->new (
36 fh => \*STDIN, 30 fh => \*STDIN,
37 on_eof => sub { 31 on_eof => sub {
38 $cv->broadcast; 32 $cv->broadcast;
39 }, 33 },
40 #TODO
41 ); 34 );
42 35
43 $cv->wait; 36 # send some request line
37 $handle->push_write ("getinfo\015\012");
38
39 # read the response line
40 $handle->push_read (line => sub {
41 my ($handle, $line) = @_;
42 warn "read line <$line>\n";
43 $cv->send;
44 });
45
46 $cv->recv;
44 47
45=head1 DESCRIPTION 48=head1 DESCRIPTION
46 49
47This module is a helper module to make it easier to do event-based I/O on 50This module is a helper module to make it easier to do event-based I/O on
48filehandles (and sockets, see L<AnyEvent::Socket> for an easy way to make 51filehandles. For utility functions for doing non-blocking connects and accepts
49non-blocking resolves and connects). 52on sockets see L<AnyEvent::Util>.
53
54The L<AnyEvent::Intro> tutorial contains some well-documented
55AnyEvent::Handle examples.
50 56
51In the following, when the documentation refers to of "bytes" then this 57In the following, when the documentation refers to of "bytes" then this
52means characters. As sysread and syswrite are used for all I/O, their 58means characters. As sysread and syswrite are used for all I/O, their
53treatment of characters applies to this module as well. 59treatment of characters applies to this module as well.
54 60
55All callbacks will be invoked with the handle object as their first 61All callbacks will be invoked with the handle object as their first
56argument. 62argument.
57 63
64=head2 SIGPIPE is not handled by this module
65
66SIGPIPE is not handled by this module, so one of the practical
67requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} =
68'IGNORE'>). At least, this is highly recommend in a networked program: If
69you use AnyEvent::Handle in a filter program (like sort), exiting on
70SIGPIPE is probably the right thing to do.
71
58=head1 METHODS 72=head1 METHODS
59 73
60=over 4 74=over 4
61 75
62=item B<new (%args)> 76=item B<new (%args)>
67 81
68=item fh => $filehandle [MANDATORY] 82=item fh => $filehandle [MANDATORY]
69 83
70The filehandle this L<AnyEvent::Handle> object will operate on. 84The filehandle this L<AnyEvent::Handle> object will operate on.
71 85
72NOTE: The filehandle will be set to non-blocking (using 86NOTE: The filehandle will be set to non-blocking mode (using
73AnyEvent::Util::fh_nonblocking). 87C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
88that mode.
74 89
75=item on_error => $cb->($self) [MANDATORY] 90=item on_eof => $cb->($handle)
76 91
77This is the fatal error callback, that is called when a fatal error ocurs, 92Set the callback to be called when an end-of-file condition is detected,
93i.e. in the case of a socket, when the other side has closed the
94connection cleanly.
95
96For sockets, this just means that the other side has stopped sending data,
97you can still try to write data, and, in fact, one can return from the eof
98callback and continue writing data, as only the read part has been shut
99down.
100
101While not mandatory, it is I<highly> recommended to set an eof callback,
102otherwise you might end up with a closed socket while you are still
103waiting for data.
104
105If an EOF condition has been detected but no C<on_eof> callback has been
106set, then a fatal error will be raised with C<$!> set to <0>.
107
108=item on_error => $cb->($handle, $fatal)
109
110This is the error callback, which is called when, well, some error
78such as not being able to resolve the hostname, failure to connect or a 111occured, such as not being able to resolve the hostname, failure to
79read error. 112connect or a read error.
80 113
81The object will not be in a usable state when this callback has been 114Some errors are fatal (which is indicated by C<$fatal> being true). On
82called. 115fatal errors the handle object will be shut down and will not be usable
116(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
117errors are an EOF condition with active (but unsatisifable) read watchers
118(C<EPIPE>) or I/O errors.
83 119
120Non-fatal errors can be retried by simply returning, but it is recommended
121to simply ignore this parameter and instead abondon the handle object
122when this callback is invoked. Examples of non-fatal errors are timeouts
123C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
124
84On callback entrance, the value of C<$!> contains the opertaing system 125On callback entrance, the value of C<$!> contains the operating system
85error (or C<ENOSPC> or C<EPIPE>). 126error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
86 127
87=item on_eof => $cb->($self) [MANDATORY] 128While not mandatory, it is I<highly> recommended to set this callback, as
129you will not be notified of errors otherwise. The default simply calls
130C<croak>.
88 131
89Set the callback to be called on EOF.
90
91=item on_read => $cb->($self) 132=item on_read => $cb->($handle)
92 133
93This sets the default read callback, which is called when data arrives 134This sets the default read callback, which is called when data arrives
94and no read request is in the queue. If the read callback is C<undef> 135and no read request is in the queue (unlike read queue callbacks, this
95or has never been set, than AnyEvent::Handle will cease reading from the 136callback will only be called when at least one octet of data is in the
96filehandle. 137read buffer).
97 138
98To access (and remove data from) the read buffer, use the C<< ->rbuf >> 139To access (and remove data from) the read buffer, use the C<< ->rbuf >>
99method or acces sthe C<$self->{rbuf}> member directly. 140method or access the C<$handle->{rbuf}> member directly.
100 141
101When an EOF condition is detected then AnyEvent::Handle will first try to 142When an EOF condition is detected then AnyEvent::Handle will first try to
102feed all the remaining data to the queued callbacks and C<on_read> before 143feed all the remaining data to the queued callbacks and C<on_read> before
103calling the C<on_eof> callback. If no progress can be made, then a fatal 144calling the C<on_eof> callback. If no progress can be made, then a fatal
104error will be raised (with C<$!> set to C<EPIPE>). 145error will be raised (with C<$!> set to C<EPIPE>).
105 146
106=item on_drain => $cb->() 147=item on_drain => $cb->($handle)
107 148
108This sets the callback that is called when the write buffer becomes empty 149This sets the callback that is called when the write buffer becomes empty
109(or when the callback is set and the buffer is empty already). 150(or when the callback is set and the buffer is empty already).
110 151
111To append to the write buffer, use the C<< ->push_write >> method. 152To append to the write buffer, use the C<< ->push_write >> method.
112 153
154This callback is useful when you don't want to put all of your write data
155into the queue at once, for example, when you want to write the contents
156of some file to the socket you might not want to read the whole file into
157memory and push it into the queue, but instead only read more data from
158the file when the write queue becomes empty.
159
160=item timeout => $fractional_seconds
161
162If non-zero, then this enables an "inactivity" timeout: whenever this many
163seconds pass without a successful read or write on the underlying file
164handle, the C<on_timeout> callback will be invoked (and if that one is
165missing, a non-fatal C<ETIMEDOUT> error will be raised).
166
167Note that timeout processing is also active when you currently do not have
168any outstanding read or write requests: If you plan to keep the connection
169idle then you should disable the timout temporarily or ignore the timeout
170in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
171restart the timeout.
172
173Zero (the default) disables this timeout.
174
175=item on_timeout => $cb->($handle)
176
177Called whenever the inactivity timeout passes. If you return from this
178callback, then the timeout will be reset as if some activity had happened,
179so this condition is not fatal in any way.
180
113=item rbuf_max => <bytes> 181=item rbuf_max => <bytes>
114 182
115If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 183If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
116when the read buffer ever (strictly) exceeds this size. This is useful to 184when the read buffer ever (strictly) exceeds this size. This is useful to
117avoid denial-of-service attacks. 185avoid some forms of denial-of-service attacks.
118 186
119For example, a server accepting connections from untrusted sources should 187For example, a server accepting connections from untrusted sources should
120be configured to accept only so-and-so much data that it cannot act on 188be configured to accept only so-and-so much data that it cannot act on
121(for example, when expecting a line, an attacker could send an unlimited 189(for example, when expecting a line, an attacker could send an unlimited
122amount of data without a callback ever being called as long as the line 190amount of data without a callback ever being called as long as the line
123isn't finished). 191isn't finished).
124 192
193=item autocork => <boolean>
194
195When disabled (the default), then C<push_write> will try to immediately
196write the data to the handle, if possible. This avoids having to register
197a write watcher and wait for the next event loop iteration, but can
198be inefficient if you write multiple small chunks (on the wire, this
199disadvantage is usually avoided by your kernel's nagle algorithm, see
200C<no_delay>, but this option can save costly syscalls).
201
202When enabled, then writes will always be queued till the next event loop
203iteration. This is efficient when you do many small writes per iteration,
204but less efficient when you do a single write only per iteration (or when
205the write buffer often is full). It also increases write latency.
206
207=item no_delay => <boolean>
208
209When doing small writes on sockets, your operating system kernel might
210wait a bit for more data before actually sending it out. This is called
211the Nagle algorithm, and usually it is beneficial.
212
213In some situations you want as low a delay as possible, which can be
214accomplishd by setting this option to a true value.
215
216The default is your opertaing system's default behaviour (most likely
217enabled), this option explicitly enables or disables it, if possible.
218
125=item read_size => <bytes> 219=item read_size => <bytes>
126 220
127The default read block size (the amount of bytes this module will try to read 221The default read block size (the amount of bytes this module will
128on each [loop iteration). Default: C<4096>. 222try to read during each loop iteration, which affects memory
223requirements). Default: C<8192>.
129 224
130=item low_water_mark => <bytes> 225=item low_water_mark => <bytes>
131 226
132Sets the amount of bytes (default: C<0>) that make up an "empty" write 227Sets the amount of bytes (default: C<0>) that make up an "empty" write
133buffer: If the write reaches this size or gets even samller it is 228buffer: If the write reaches this size or gets even samller it is
134considered empty. 229considered empty.
135 230
231Sometimes it can be beneficial (for performance reasons) to add data to
232the write buffer before it is fully drained, but this is a rare case, as
233the operating system kernel usually buffers data as well, so the default
234is good in almost all cases.
235
236=item linger => <seconds>
237
238If non-zero (default: C<3600>), then the destructor of the
239AnyEvent::Handle object will check whether there is still outstanding
240write data and will install a watcher that will write this data to the
241socket. No errors will be reported (this mostly matches how the operating
242system treats outstanding data at socket close time).
243
244This will not work for partial TLS data that could not be encoded
245yet. This data will be lost. Calling the C<stoptls> method in time might
246help.
247
248=item tls => "accept" | "connect" | Net::SSLeay::SSL object
249
250When this parameter is given, it enables TLS (SSL) mode, that means
251AnyEvent will start a TLS handshake as soon as the conenction has been
252established and will transparently encrypt/decrypt data afterwards.
253
254TLS mode requires Net::SSLeay to be installed (it will be loaded
255automatically when you try to create a TLS handle): this module doesn't
256have a dependency on that module, so if your module requires it, you have
257to add the dependency yourself.
258
259Unlike TCP, TLS has a server and client side: for the TLS server side, use
260C<accept>, and for the TLS client side of a connection, use C<connect>
261mode.
262
263You can also provide your own TLS connection object, but you have
264to make sure that you call either C<Net::SSLeay::set_connect_state>
265or C<Net::SSLeay::set_accept_state> on it before you pass it to
266AnyEvent::Handle.
267
268See the C<< ->starttls >> method for when need to start TLS negotiation later.
269
270=item tls_ctx => $ssl_ctx
271
272Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
273(unless a connection object was specified directly). If this parameter is
274missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
275
276=item json => JSON or JSON::XS object
277
278This is the json coder object used by the C<json> read and write types.
279
280If you don't supply it, then AnyEvent::Handle will create and use a
281suitable one (on demand), which will write and expect UTF-8 encoded JSON
282texts.
283
284Note that you are responsible to depend on the JSON module if you want to
285use this functionality, as AnyEvent does not have a dependency itself.
286
136=back 287=back
137 288
138=cut 289=cut
139 290
140sub new { 291sub new {
144 295
145 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 296 $self->{fh} or Carp::croak "mandatory argument fh is missing";
146 297
147 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 298 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
148 299
149 $self->on_error ((delete $self->{on_error}) or Carp::croak "mandatory argument on_error is missing"); 300 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
150 $self->on_eof ((delete $self->{on_eof} ) or Carp::croak "mandatory argument on_eof is missing"); 301 if $self->{tls};
151 302
303 $self->{_activity} = AnyEvent->now;
304 $self->_timeout;
305
152 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 306 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
153 $self->on_read (delete $self->{on_read} ) if $self->{on_read}; 307 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
308
309 $self->start_read
310 if $self->{on_read};
154 311
155 $self 312 $self
156} 313}
157 314
158sub _shutdown { 315sub _shutdown {
159 my ($self) = @_; 316 my ($self) = @_;
160 317
318 delete $self->{_tw};
161 delete $self->{rw}; 319 delete $self->{_rw};
162 delete $self->{ww}; 320 delete $self->{_ww};
163 delete $self->{fh}; 321 delete $self->{fh};
164}
165 322
323 &_freetls;
324
325 delete $self->{on_read};
326 delete $self->{_queue};
327}
328
166sub error { 329sub _error {
167 my ($self) = @_; 330 my ($self, $errno, $fatal) = @_;
168 331
169 {
170 local $!;
171 $self->_shutdown; 332 $self->_shutdown
172 } 333 if $fatal;
173 334
335 $! = $errno;
336
337 if ($self->{on_error}) {
174 $self->{on_error}($self); 338 $self->{on_error}($self, $fatal);
339 } else {
340 Carp::croak "AnyEvent::Handle uncaught error: $!";
341 }
175} 342}
176 343
177=item $fh = $handle->fh 344=item $fh = $handle->fh
178 345
179This method returns the filehandle of the L<AnyEvent::Handle> object. 346This method returns the file handle used to create the L<AnyEvent::Handle> object.
180 347
181=cut 348=cut
182 349
183sub fh { $_[0]->{fh} } 350sub fh { $_[0]{fh} }
184 351
185=item $handle->on_error ($cb) 352=item $handle->on_error ($cb)
186 353
187Replace the current C<on_error> callback (see the C<on_error> constructor argument). 354Replace the current C<on_error> callback (see the C<on_error> constructor argument).
188 355
200 367
201sub on_eof { 368sub on_eof {
202 $_[0]{on_eof} = $_[1]; 369 $_[0]{on_eof} = $_[1];
203} 370}
204 371
372=item $handle->on_timeout ($cb)
373
374Replace the current C<on_timeout> callback, or disables the callback (but
375not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
376argument and method.
377
378=cut
379
380sub on_timeout {
381 $_[0]{on_timeout} = $_[1];
382}
383
384=item $handle->autocork ($boolean)
385
386Enables or disables the current autocork behaviour (see C<autocork>
387constructor argument).
388
389=cut
390
391=item $handle->no_delay ($boolean)
392
393Enables or disables the C<no_delay> setting (see constructor argument of
394the same name for details).
395
396=cut
397
398sub no_delay {
399 $_[0]{no_delay} = $_[1];
400
401 eval {
402 local $SIG{__DIE__};
403 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
404 };
405}
406
407#############################################################################
408
409=item $handle->timeout ($seconds)
410
411Configures (or disables) the inactivity timeout.
412
413=cut
414
415sub timeout {
416 my ($self, $timeout) = @_;
417
418 $self->{timeout} = $timeout;
419 $self->_timeout;
420}
421
422# reset the timeout watcher, as neccessary
423# also check for time-outs
424sub _timeout {
425 my ($self) = @_;
426
427 if ($self->{timeout}) {
428 my $NOW = AnyEvent->now;
429
430 # when would the timeout trigger?
431 my $after = $self->{_activity} + $self->{timeout} - $NOW;
432
433 # now or in the past already?
434 if ($after <= 0) {
435 $self->{_activity} = $NOW;
436
437 if ($self->{on_timeout}) {
438 $self->{on_timeout}($self);
439 } else {
440 $self->_error (&Errno::ETIMEDOUT);
441 }
442
443 # callback could have changed timeout value, optimise
444 return unless $self->{timeout};
445
446 # calculate new after
447 $after = $self->{timeout};
448 }
449
450 Scalar::Util::weaken $self;
451 return unless $self; # ->error could have destroyed $self
452
453 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
454 delete $self->{_tw};
455 $self->_timeout;
456 });
457 } else {
458 delete $self->{_tw};
459 }
460}
461
205############################################################################# 462#############################################################################
206 463
207=back 464=back
208 465
209=head2 WRITE QUEUE 466=head2 WRITE QUEUE
212for reading. 469for reading.
213 470
214The write queue is very simple: you can add data to its end, and 471The write queue is very simple: you can add data to its end, and
215AnyEvent::Handle will automatically try to get rid of it for you. 472AnyEvent::Handle will automatically try to get rid of it for you.
216 473
217When data could be writtena nd the write buffer is shorter then the low 474When data could be written and the write buffer is shorter then the low
218water mark, the C<on_drain> callback will be invoked. 475water mark, the C<on_drain> callback will be invoked.
219 476
220=over 4 477=over 4
221 478
222=item $handle->on_drain ($cb) 479=item $handle->on_drain ($cb)
230 my ($self, $cb) = @_; 487 my ($self, $cb) = @_;
231 488
232 $self->{on_drain} = $cb; 489 $self->{on_drain} = $cb;
233 490
234 $cb->($self) 491 $cb->($self)
235 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 492 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
236} 493}
237 494
238=item $handle->push_write ($data) 495=item $handle->push_write ($data)
239 496
240Queues the given scalar to be written. You can push as much data as you 497Queues the given scalar to be written. You can push as much data as you
241want (only limited by the available memory), as C<AnyEvent::Handle> 498want (only limited by the available memory), as C<AnyEvent::Handle>
242buffers it independently of the kernel. 499buffers it independently of the kernel.
243 500
244=cut 501=cut
245 502
246sub push_write { 503sub _drain_wbuf {
247 my ($self, $data) = @_; 504 my ($self) = @_;
248 505
249 $self->{wbuf} .= $data; 506 if (!$self->{_ww} && length $self->{wbuf}) {
250 507
251 unless ($self->{ww}) {
252 Scalar::Util::weaken $self; 508 Scalar::Util::weaken $self;
509
253 my $cb = sub { 510 my $cb = sub {
254 my $len = syswrite $self->{fh}, $self->{wbuf}; 511 my $len = syswrite $self->{fh}, $self->{wbuf};
255 512
256 if ($len > 0) { 513 if ($len >= 0) {
257 substr $self->{wbuf}, 0, $len, ""; 514 substr $self->{wbuf}, 0, $len, "";
258 515
516 $self->{_activity} = AnyEvent->now;
259 517
260 $self->{on_drain}($self) 518 $self->{on_drain}($self)
261 if $self->{low_water_mark} >= length $self->{wbuf} 519 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
262 && $self->{on_drain}; 520 && $self->{on_drain};
263 521
264 delete $self->{ww} unless length $self->{wbuf}; 522 delete $self->{_ww} unless length $self->{wbuf};
265 } elsif ($! != EAGAIN && $! != EINTR) { 523 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
266 $self->error; 524 $self->_error ($!, 1);
267 } 525 }
268 }; 526 };
269 527
528 # try to write data immediately
529 $cb->() unless $self->{autocork};
530
531 # if still data left in wbuf, we need to poll
270 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb); 532 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
271 533 if length $self->{wbuf};
272 $cb->($self);
273 }; 534 };
274} 535}
536
537our %WH;
538
539sub register_write_type($$) {
540 $WH{$_[0]} = $_[1];
541}
542
543sub push_write {
544 my $self = shift;
545
546 if (@_ > 1) {
547 my $type = shift;
548
549 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
550 ->($self, @_);
551 }
552
553 if ($self->{tls}) {
554 $self->{_tls_wbuf} .= $_[0];
555 &_dotls ($self);
556 } else {
557 $self->{wbuf} .= $_[0];
558 $self->_drain_wbuf;
559 }
560}
561
562=item $handle->push_write (type => @args)
563
564Instead of formatting your data yourself, you can also let this module do
565the job by specifying a type and type-specific arguments.
566
567Predefined types are (if you have ideas for additional types, feel free to
568drop by and tell us):
569
570=over 4
571
572=item netstring => $string
573
574Formats the given value as netstring
575(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
576
577=cut
578
579register_write_type netstring => sub {
580 my ($self, $string) = @_;
581
582 sprintf "%d:%s,", (length $string), $string
583};
584
585=item packstring => $format, $data
586
587An octet string prefixed with an encoded length. The encoding C<$format>
588uses the same format as a Perl C<pack> format, but must specify a single
589integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
590optional C<!>, C<< < >> or C<< > >> modifier).
591
592=cut
593
594register_write_type packstring => sub {
595 my ($self, $format, $string) = @_;
596
597 pack "$format/a*", $string
598};
599
600=item json => $array_or_hashref
601
602Encodes the given hash or array reference into a JSON object. Unless you
603provide your own JSON object, this means it will be encoded to JSON text
604in UTF-8.
605
606JSON objects (and arrays) are self-delimiting, so you can write JSON at
607one end of a handle and read them at the other end without using any
608additional framing.
609
610The generated JSON text is guaranteed not to contain any newlines: While
611this module doesn't need delimiters after or between JSON texts to be
612able to read them, many other languages depend on that.
613
614A simple RPC protocol that interoperates easily with others is to send
615JSON arrays (or objects, although arrays are usually the better choice as
616they mimic how function argument passing works) and a newline after each
617JSON text:
618
619 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
620 $handle->push_write ("\012");
621
622An AnyEvent::Handle receiver would simply use the C<json> read type and
623rely on the fact that the newline will be skipped as leading whitespace:
624
625 $handle->push_read (json => sub { my $array = $_[1]; ... });
626
627Other languages could read single lines terminated by a newline and pass
628this line into their JSON decoder of choice.
629
630=cut
631
632register_write_type json => sub {
633 my ($self, $ref) = @_;
634
635 require JSON;
636
637 $self->{json} ? $self->{json}->encode ($ref)
638 : JSON::encode_json ($ref)
639};
640
641=item storable => $reference
642
643Freezes the given reference using L<Storable> and writes it to the
644handle. Uses the C<nfreeze> format.
645
646=cut
647
648register_write_type storable => sub {
649 my ($self, $ref) = @_;
650
651 require Storable;
652
653 pack "w/a*", Storable::nfreeze ($ref)
654};
655
656=back
657
658=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
659
660This function (not method) lets you add your own types to C<push_write>.
661Whenever the given C<type> is used, C<push_write> will invoke the code
662reference with the handle object and the remaining arguments.
663
664The code reference is supposed to return a single octet string that will
665be appended to the write buffer.
666
667Note that this is a function, and all types registered this way will be
668global, so try to use unique names.
669
670=cut
275 671
276############################################################################# 672#############################################################################
277 673
278=back 674=back
279 675
286ways, the "simple" way, using only C<on_read> and the "complex" way, using 682ways, the "simple" way, using only C<on_read> and the "complex" way, using
287a queue. 683a queue.
288 684
289In the simple case, you just install an C<on_read> callback and whenever 685In the simple case, you just install an C<on_read> callback and whenever
290new data arrives, it will be called. You can then remove some data (if 686new data arrives, it will be called. You can then remove some data (if
291enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 687enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
292or not. 688leave the data there if you want to accumulate more (e.g. when only a
689partial message has been received so far).
293 690
294In the more complex case, you want to queue multiple callbacks. In this 691In the more complex case, you want to queue multiple callbacks. In this
295case, AnyEvent::Handle will call the first queued callback each time new 692case, AnyEvent::Handle will call the first queued callback each time new
296data arrives and removes it when it has done its job (see C<push_read>, 693data arrives (also the first time it is queued) and removes it when it has
297below). 694done its job (see C<push_read>, below).
298 695
299This way you can, for example, push three line-reads, followed by reading 696This way you can, for example, push three line-reads, followed by reading
300a chunk of data, and AnyEvent::Handle will execute them in order. 697a chunk of data, and AnyEvent::Handle will execute them in order.
301 698
302Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 699Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
303the specified number of bytes which give an XML datagram. 700the specified number of bytes which give an XML datagram.
304 701
305 # in the default state, expect some header bytes 702 # in the default state, expect some header bytes
306 $handle->on_read (sub { 703 $handle->on_read (sub {
307 # some data is here, now queue the length-header-read (4 octets) 704 # some data is here, now queue the length-header-read (4 octets)
308 shift->unshift_read_chunk (4, sub { 705 shift->unshift_read (chunk => 4, sub {
309 # header arrived, decode 706 # header arrived, decode
310 my $len = unpack "N", $_[1]; 707 my $len = unpack "N", $_[1];
311 708
312 # now read the payload 709 # now read the payload
313 shift->unshift_read_chunk ($len, sub { 710 shift->unshift_read (chunk => $len, sub {
314 my $xml = $_[1]; 711 my $xml = $_[1];
315 # handle xml 712 # handle xml
316 }); 713 });
317 }); 714 });
318 }); 715 });
319 716
320Example 2: Implement a client for a protocol that replies either with 717Example 2: Implement a client for a protocol that replies either with "OK"
321"OK" and another line or "ERROR" for one request, and 64 bytes for the 718and another line or "ERROR" for the first request that is sent, and 64
322second request. Due tot he availability of a full queue, we can just 719bytes for the second request. Due to the availability of a queue, we can
323pipeline sending both requests and manipulate the queue as necessary in 720just pipeline sending both requests and manipulate the queue as necessary
324the callbacks: 721in the callbacks.
325 722
326 # request one 723When the first callback is called and sees an "OK" response, it will
724C<unshift> another line-read. This line-read will be queued I<before> the
72564-byte chunk callback.
726
727 # request one, returns either "OK + extra line" or "ERROR"
327 $handle->push_write ("request 1\015\012"); 728 $handle->push_write ("request 1\015\012");
328 729
329 # we expect "ERROR" or "OK" as response, so push a line read 730 # we expect "ERROR" or "OK" as response, so push a line read
330 $handle->push_read_line (sub { 731 $handle->push_read (line => sub {
331 # if we got an "OK", we have to _prepend_ another line, 732 # if we got an "OK", we have to _prepend_ another line,
332 # so it will be read before the second request reads its 64 bytes 733 # so it will be read before the second request reads its 64 bytes
333 # which are already in the queue when this callback is called 734 # which are already in the queue when this callback is called
334 # we don't do this in case we got an error 735 # we don't do this in case we got an error
335 if ($_[1] eq "OK") { 736 if ($_[1] eq "OK") {
336 $_[0]->unshift_read_line (sub { 737 $_[0]->unshift_read (line => sub {
337 my $response = $_[1]; 738 my $response = $_[1];
338 ... 739 ...
339 }); 740 });
340 } 741 }
341 }); 742 });
342 743
343 # request two 744 # request two, simply returns 64 octets
344 $handle->push_write ("request 2\015\012"); 745 $handle->push_write ("request 2\015\012");
345 746
346 # simply read 64 bytes, always 747 # simply read 64 bytes, always
347 $handle->push_read_chunk (64, sub { 748 $handle->push_read (chunk => 64, sub {
348 my $response = $_[1]; 749 my $response = $_[1];
349 ... 750 ...
350 }); 751 });
351 752
352=over 4 753=over 4
353 754
755=cut
756
354sub _drain_rbuf { 757sub _drain_rbuf {
355 my ($self) = @_; 758 my ($self) = @_;
356 759
357 return if exists $self->{in_drain};
358 local $self->{in_drain} = 1; 760 local $self->{_in_drain} = 1;
359 761
762 if (
763 defined $self->{rbuf_max}
764 && $self->{rbuf_max} < length $self->{rbuf}
765 ) {
766 $self->_error (&Errno::ENOSPC, 1), return;
767 }
768
769 while () {
360 while (my $len = length $self->{rbuf}) { 770 my $len = length $self->{rbuf};
361 no strict 'refs'; 771
362 if (@{ $self->{queue} }) { 772 if (my $cb = shift @{ $self->{_queue} }) {
363 if ($self->{queue}[0]($self)) { 773 unless ($cb->($self)) {
364 shift @{ $self->{queue} };
365 } elsif ($self->{eof}) { 774 if ($self->{_eof}) {
366 # no progress can be made (not enough data and no data forthcoming) 775 # no progress can be made (not enough data and no data forthcoming)
367 $! = &Errno::EPIPE; return $self->error; 776 $self->_error (&Errno::EPIPE, 1), return;
368 } else { 777 }
778
779 unshift @{ $self->{_queue} }, $cb;
369 return; 780 last;
370 } 781 }
371 } elsif ($self->{on_read}) { 782 } elsif ($self->{on_read}) {
783 last unless $len;
784
372 $self->{on_read}($self); 785 $self->{on_read}($self);
373 786
374 if ( 787 if (
375 $self->{eof} # if no further data will arrive
376 && $len == length $self->{rbuf} # and no data has been consumed 788 $len == length $self->{rbuf} # if no data has been consumed
377 && !@{ $self->{queue} } # and the queue is still empty 789 && !@{ $self->{_queue} } # and the queue is still empty
378 && $self->{on_read} # and we still want to read data 790 && $self->{on_read} # but we still have on_read
379 ) { 791 ) {
792 # no further data will arrive
380 # then no progress can be made 793 # so no progress can be made
381 $! = &Errno::EPIPE; return $self->error; 794 $self->_error (&Errno::EPIPE, 1), return
795 if $self->{_eof};
796
797 last; # more data might arrive
382 } 798 }
383 } else { 799 } else {
384 # read side becomes idle 800 # read side becomes idle
385 delete $self->{rw}; 801 delete $self->{_rw} unless $self->{tls};
386 return; 802 last;
387 } 803 }
388 } 804 }
389 805
390 if ($self->{eof}) { 806 if ($self->{_eof}) {
391 $self->_shutdown; 807 if ($self->{on_eof}) {
392 $self->{on_eof}($self); 808 $self->{on_eof}($self)
809 } else {
810 $self->_error (0, 1);
811 }
812 }
813
814 # may need to restart read watcher
815 unless ($self->{_rw}) {
816 $self->start_read
817 if $self->{on_read} || @{ $self->{_queue} };
393 } 818 }
394} 819}
395 820
396=item $handle->on_read ($cb) 821=item $handle->on_read ($cb)
397 822
403 828
404sub on_read { 829sub on_read {
405 my ($self, $cb) = @_; 830 my ($self, $cb) = @_;
406 831
407 $self->{on_read} = $cb; 832 $self->{on_read} = $cb;
408 833 $self->_drain_rbuf if $cb && !$self->{_in_drain};
409 unless ($self->{rw} || $self->{eof}) {
410 Scalar::Util::weaken $self;
411
412 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
413 my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} || 8192, length $self->{rbuf};
414
415 if ($len > 0) {
416 if (exists $self->{rbuf_max}) {
417 if ($self->{rbuf_max} < length $self->{rbuf}) {
418 $! = &Errno::ENOSPC; return $self->error;
419 }
420 }
421
422 } elsif (defined $len) {
423 $self->{eof} = 1;
424 delete $self->{rw};
425
426 } elsif ($! != EAGAIN && $! != EINTR) {
427 return $self->error;
428 }
429
430 $self->_drain_rbuf;
431 });
432 }
433} 834}
434 835
435=item $handle->rbuf 836=item $handle->rbuf
436 837
437Returns the read buffer (as a modifiable lvalue). 838Returns the read buffer (as a modifiable lvalue).
456Append the given callback to the end of the queue (C<push_read>) or 857Append the given callback to the end of the queue (C<push_read>) or
457prepend it (C<unshift_read>). 858prepend it (C<unshift_read>).
458 859
459The callback is called each time some additional read data arrives. 860The callback is called each time some additional read data arrives.
460 861
461It must check wether enough data is in the read buffer already. 862It must check whether enough data is in the read buffer already.
462 863
463If not enough data is available, it must return the empty list or a false 864If not enough data is available, it must return the empty list or a false
464value, in which case it will be called repeatedly until enough data is 865value, in which case it will be called repeatedly until enough data is
465available (or an error condition is detected). 866available (or an error condition is detected).
466 867
468interested in (which can be none at all) and return a true value. After returning 869interested in (which can be none at all) and return a true value. After returning
469true, it will be removed from the queue. 870true, it will be removed from the queue.
470 871
471=cut 872=cut
472 873
874our %RH;
875
876sub register_read_type($$) {
877 $RH{$_[0]} = $_[1];
878}
879
473sub push_read { 880sub push_read {
474 my ($self, $cb) = @_; 881 my $self = shift;
882 my $cb = pop;
475 883
884 if (@_) {
885 my $type = shift;
886
887 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
888 ->($self, $cb, @_);
889 }
890
476 push @{ $self->{queue} }, $cb; 891 push @{ $self->{_queue} }, $cb;
477 $self->_drain_rbuf; 892 $self->_drain_rbuf unless $self->{_in_drain};
478} 893}
479 894
480sub unshift_read { 895sub unshift_read {
481 my ($self, $cb) = @_; 896 my $self = shift;
897 my $cb = pop;
482 898
899 if (@_) {
900 my $type = shift;
901
902 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
903 ->($self, $cb, @_);
904 }
905
906
483 push @{ $self->{queue} }, $cb; 907 unshift @{ $self->{_queue} }, $cb;
484 $self->_drain_rbuf; 908 $self->_drain_rbuf unless $self->{_in_drain};
485} 909}
486 910
487=item $handle->push_read_chunk ($len, $cb->($self, $data)) 911=item $handle->push_read (type => @args, $cb)
488 912
489=item $handle->unshift_read_chunk ($len, $cb->($self, $data)) 913=item $handle->unshift_read (type => @args, $cb)
490 914
491Append the given callback to the end of the queue (C<push_read_chunk>) or 915Instead of providing a callback that parses the data itself you can chose
492prepend it (C<unshift_read_chunk>). 916between a number of predefined parsing formats, for chunks of data, lines
917etc.
493 918
494The callback will be called only once C<$len> bytes have been read, and 919Predefined types are (if you have ideas for additional types, feel free to
495these C<$len> bytes will be passed to the callback. 920drop by and tell us):
496 921
497=cut 922=over 4
498 923
499sub _read_chunk($$) { 924=item chunk => $octets, $cb->($handle, $data)
500 my ($len, $cb) = @_; 925
926Invoke the callback only once C<$octets> bytes have been read. Pass the
927data read to the callback. The callback will never be called with less
928data.
929
930Example: read 2 bytes.
931
932 $handle->push_read (chunk => 2, sub {
933 warn "yay ", unpack "H*", $_[1];
934 });
935
936=cut
937
938register_read_type chunk => sub {
939 my ($self, $cb, $len) = @_;
501 940
502 sub { 941 sub {
503 $len <= length $_[0]{rbuf} or return; 942 $len <= length $_[0]{rbuf} or return;
504 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 943 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
505 1 944 1
506 } 945 }
507} 946};
508 947
509sub push_read_chunk { 948=item line => [$eol, ]$cb->($handle, $line, $eol)
510 my ($self, $len, $cb) = @_;
511
512 $self->push_read (_read_chunk $len, $cb);
513}
514
515
516sub unshift_read_chunk {
517 my ($self, $len, $cb) = @_;
518
519 $self->unshift_read (_read_chunk $len, $cb);
520}
521
522=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol))
523
524=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
525
526Append the given callback to the end of the queue (C<push_read_line>) or
527prepend it (C<unshift_read_line>).
528 949
529The callback will be called only once a full line (including the end of 950The callback will be called only once a full line (including the end of
530line marker, C<$eol>) has been read. This line (excluding the end of line 951line marker, C<$eol>) has been read. This line (excluding the end of line
531marker) will be passed to the callback as second argument (C<$line>), and 952marker) will be passed to the callback as second argument (C<$line>), and
532the end of line marker as the third argument (C<$eol>). 953the end of line marker as the third argument (C<$eol>).
543Partial lines at the end of the stream will never be returned, as they are 964Partial lines at the end of the stream will never be returned, as they are
544not marked by the end of line marker. 965not marked by the end of line marker.
545 966
546=cut 967=cut
547 968
548sub _read_line($$) { 969register_read_type line => sub {
549 my $cb = pop; 970 my ($self, $cb, $eol) = @_;
550 my $eol = @_ ? shift : qr|(\015?\012)|;
551 my $pos;
552 971
972 if (@_ < 3) {
973 # this is more than twice as fast as the generic code below
974 sub {
975 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
976
977 $cb->($_[0], $1, $2);
978 1
979 }
980 } else {
553 $eol = qr|(\Q$eol\E)| unless ref $eol; 981 $eol = quotemeta $eol unless ref $eol;
554 $eol = qr|^(.*?)($eol)|; 982 $eol = qr|^(.*?)($eol)|s;
983
984 sub {
985 $_[0]{rbuf} =~ s/$eol// or return;
986
987 $cb->($_[0], $1, $2);
988 1
989 }
990 }
991};
992
993=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
994
995Makes a regex match against the regex object C<$accept> and returns
996everything up to and including the match.
997
998Example: read a single line terminated by '\n'.
999
1000 $handle->push_read (regex => qr<\n>, sub { ... });
1001
1002If C<$reject> is given and not undef, then it determines when the data is
1003to be rejected: it is matched against the data when the C<$accept> regex
1004does not match and generates an C<EBADMSG> error when it matches. This is
1005useful to quickly reject wrong data (to avoid waiting for a timeout or a
1006receive buffer overflow).
1007
1008Example: expect a single decimal number followed by whitespace, reject
1009anything else (not the use of an anchor).
1010
1011 $handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
1012
1013If C<$skip> is given and not C<undef>, then it will be matched against
1014the receive buffer when neither C<$accept> nor C<$reject> match,
1015and everything preceding and including the match will be accepted
1016unconditionally. This is useful to skip large amounts of data that you
1017know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1018have to start matching from the beginning. This is purely an optimisation
1019and is usually worth only when you expect more than a few kilobytes.
1020
1021Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1022expect the header to be very large (it isn't in practise, but...), we use
1023a skip regex to skip initial portions. The skip regex is tricky in that
1024it only accepts something not ending in either \015 or \012, as these are
1025required for the accept regex.
1026
1027 $handle->push_read (regex =>
1028 qr<\015\012\015\012>,
1029 undef, # no reject
1030 qr<^.*[^\015\012]>,
1031 sub { ... });
1032
1033=cut
1034
1035register_read_type regex => sub {
1036 my ($self, $cb, $accept, $reject, $skip) = @_;
1037
1038 my $data;
1039 my $rbuf = \$self->{rbuf};
555 1040
556 sub { 1041 sub {
557 $_[0]{rbuf} =~ s/$eol// or return; 1042 # accept
1043 if ($$rbuf =~ $accept) {
1044 $data .= substr $$rbuf, 0, $+[0], "";
1045 $cb->($self, $data);
1046 return 1;
1047 }
1048
1049 # reject
1050 if ($reject && $$rbuf =~ $reject) {
1051 $self->_error (&Errno::EBADMSG);
1052 }
558 1053
559 $cb->($1, $2); 1054 # skip
1055 if ($skip && $$rbuf =~ $skip) {
1056 $data .= substr $$rbuf, 0, $+[0], "";
1057 }
1058
1059 ()
1060 }
1061};
1062
1063=item netstring => $cb->($handle, $string)
1064
1065A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1066
1067Throws an error with C<$!> set to EBADMSG on format violations.
1068
1069=cut
1070
1071register_read_type netstring => sub {
1072 my ($self, $cb) = @_;
1073
1074 sub {
1075 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1076 if ($_[0]{rbuf} =~ /[^0-9]/) {
1077 $self->_error (&Errno::EBADMSG);
1078 }
1079 return;
1080 }
1081
1082 my $len = $1;
1083
1084 $self->unshift_read (chunk => $len, sub {
1085 my $string = $_[1];
1086 $_[0]->unshift_read (chunk => 1, sub {
1087 if ($_[1] eq ",") {
1088 $cb->($_[0], $string);
1089 } else {
1090 $self->_error (&Errno::EBADMSG);
1091 }
1092 });
1093 });
1094
560 1 1095 1
561 } 1096 }
562} 1097};
563 1098
564sub push_read_line { 1099=item packstring => $format, $cb->($handle, $string)
1100
1101An octet string prefixed with an encoded length. The encoding C<$format>
1102uses the same format as a Perl C<pack> format, but must specify a single
1103integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1104optional C<!>, C<< < >> or C<< > >> modifier).
1105
1106DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>.
1107
1108Example: read a block of data prefixed by its length in BER-encoded
1109format (very efficient).
1110
1111 $handle->push_read (packstring => "w", sub {
1112 my ($handle, $data) = @_;
1113 });
1114
1115=cut
1116
1117register_read_type packstring => sub {
1118 my ($self, $cb, $format) = @_;
1119
1120 sub {
1121 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1122 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1123 or return;
1124
1125 $format = length pack $format, $len;
1126
1127 # bypass unshift if we already have the remaining chunk
1128 if ($format + $len <= length $_[0]{rbuf}) {
1129 my $data = substr $_[0]{rbuf}, $format, $len;
1130 substr $_[0]{rbuf}, 0, $format + $len, "";
1131 $cb->($_[0], $data);
1132 } else {
1133 # remove prefix
1134 substr $_[0]{rbuf}, 0, $format, "";
1135
1136 # read remaining chunk
1137 $_[0]->unshift_read (chunk => $len, $cb);
1138 }
1139
1140 1
1141 }
1142};
1143
1144=item json => $cb->($handle, $hash_or_arrayref)
1145
1146Reads a JSON object or array, decodes it and passes it to the callback.
1147
1148If a C<json> object was passed to the constructor, then that will be used
1149for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1150
1151This read type uses the incremental parser available with JSON version
11522.09 (and JSON::XS version 2.2) and above. You have to provide a
1153dependency on your own: this module will load the JSON module, but
1154AnyEvent does not depend on it itself.
1155
1156Since JSON texts are fully self-delimiting, the C<json> read and write
1157types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1158the C<json> write type description, above, for an actual example.
1159
1160=cut
1161
1162register_read_type json => sub {
1163 my ($self, $cb) = @_;
1164
1165 require JSON;
1166
1167 my $data;
1168 my $rbuf = \$self->{rbuf};
1169
1170 my $json = $self->{json} ||= JSON->new->utf8;
1171
1172 sub {
1173 my $ref = $json->incr_parse ($self->{rbuf});
1174
1175 if ($ref) {
1176 $self->{rbuf} = $json->incr_text;
1177 $json->incr_text = "";
1178 $cb->($self, $ref);
1179
1180 1
1181 } else {
1182 $self->{rbuf} = "";
1183 ()
1184 }
1185 }
1186};
1187
1188=item storable => $cb->($handle, $ref)
1189
1190Deserialises a L<Storable> frozen representation as written by the
1191C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1192data).
1193
1194Raises C<EBADMSG> error if the data could not be decoded.
1195
1196=cut
1197
1198register_read_type storable => sub {
1199 my ($self, $cb) = @_;
1200
1201 require Storable;
1202
1203 sub {
1204 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1205 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1206 or return;
1207
1208 my $format = length pack "w", $len;
1209
1210 # bypass unshift if we already have the remaining chunk
1211 if ($format + $len <= length $_[0]{rbuf}) {
1212 my $data = substr $_[0]{rbuf}, $format, $len;
1213 substr $_[0]{rbuf}, 0, $format + $len, "";
1214 $cb->($_[0], Storable::thaw ($data));
1215 } else {
1216 # remove prefix
1217 substr $_[0]{rbuf}, 0, $format, "";
1218
1219 # read remaining chunk
1220 $_[0]->unshift_read (chunk => $len, sub {
1221 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1222 $cb->($_[0], $ref);
1223 } else {
1224 $self->_error (&Errno::EBADMSG);
1225 }
1226 });
1227 }
1228
1229 1
1230 }
1231};
1232
1233=back
1234
1235=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
1236
1237This function (not method) lets you add your own types to C<push_read>.
1238
1239Whenever the given C<type> is used, C<push_read> will invoke the code
1240reference with the handle object, the callback and the remaining
1241arguments.
1242
1243The code reference is supposed to return a callback (usually a closure)
1244that works as a plain read callback (see C<< ->push_read ($cb) >>).
1245
1246It should invoke the passed callback when it is done reading (remember to
1247pass C<$handle> as first argument as all other callbacks do that).
1248
1249Note that this is a function, and all types registered this way will be
1250global, so try to use unique names.
1251
1252For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
1253search for C<register_read_type>)).
1254
1255=item $handle->stop_read
1256
1257=item $handle->start_read
1258
1259In rare cases you actually do not want to read anything from the
1260socket. In this case you can call C<stop_read>. Neither C<on_read> nor
1261any queued callbacks will be executed then. To start reading again, call
1262C<start_read>.
1263
1264Note that AnyEvent::Handle will automatically C<start_read> for you when
1265you change the C<on_read> callback or push/unshift a read callback, and it
1266will automatically C<stop_read> for you when neither C<on_read> is set nor
1267there are any read requests in the queue.
1268
1269These methods will have no effect when in TLS mode (as TLS doesn't support
1270half-duplex connections).
1271
1272=cut
1273
1274sub stop_read {
1275 my ($self) = @_;
1276
1277 delete $self->{_rw} unless $self->{tls};
1278}
1279
1280sub start_read {
1281 my ($self) = @_;
1282
1283 unless ($self->{_rw} || $self->{_eof}) {
1284 Scalar::Util::weaken $self;
1285
1286 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1287 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1288 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1289
1290 if ($len > 0) {
1291 $self->{_activity} = AnyEvent->now;
1292
1293 if ($self->{tls}) {
1294 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1295 &_dotls ($self);
1296 } else {
1297 $self->_drain_rbuf unless $self->{_in_drain};
1298 }
1299
1300 } elsif (defined $len) {
1301 delete $self->{_rw};
1302 $self->{_eof} = 1;
1303 $self->_drain_rbuf unless $self->{_in_drain};
1304
1305 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1306 return $self->_error ($!, 1);
1307 }
1308 });
1309 }
1310}
1311
1312sub _dotls {
1313 my ($self) = @_;
1314
1315 my $buf;
1316
1317 if (length $self->{_tls_wbuf}) {
1318 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1319 substr $self->{_tls_wbuf}, 0, $len, "";
1320 }
1321 }
1322
1323 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) {
1324 unless (length $buf) {
1325 # let's treat SSL-eof as we treat normal EOF
1326 delete $self->{_rw};
1327 $self->{_eof} = 1;
1328 &_freetls;
1329 }
1330
1331 $self->{rbuf} .= $buf;
1332 $self->_drain_rbuf unless $self->{_in_drain};
1333 $self->{tls} or return; # tls session might have gone away in callback
1334 }
1335
1336 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1337
1338 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1339 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1340 return $self->_error ($!, 1);
1341 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1342 return $self->_error (&Errno::EIO, 1);
1343 }
1344
1345 # all others are fine for our purposes
1346 }
1347
1348 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1349 $self->{wbuf} .= $buf;
1350 $self->_drain_wbuf;
1351 }
1352}
1353
1354=item $handle->starttls ($tls[, $tls_ctx])
1355
1356Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1357object is created, you can also do that at a later time by calling
1358C<starttls>.
1359
1360The first argument is the same as the C<tls> constructor argument (either
1361C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1362
1363The second argument is the optional C<Net::SSLeay::CTX> object that is
1364used when AnyEvent::Handle has to create its own TLS connection object.
1365
1366The TLS connection object will end up in C<< $handle->{tls} >> after this
1367call and can be used or changed to your liking. Note that the handshake
1368might have already started when this function returns.
1369
1370If it an error to start a TLS handshake more than once per
1371AnyEvent::Handle object (this is due to bugs in OpenSSL).
1372
1373=cut
1374
1375sub starttls {
1376 my ($self, $ssl, $ctx) = @_;
1377
1378 require Net::SSLeay;
1379
1380 Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object"
1381 if $self->{tls};
1382
1383 if ($ssl eq "accept") {
1384 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1385 Net::SSLeay::set_accept_state ($ssl);
1386 } elsif ($ssl eq "connect") {
1387 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1388 Net::SSLeay::set_connect_state ($ssl);
1389 }
1390
1391 $self->{tls} = $ssl;
1392
1393 # basically, this is deep magic (because SSL_read should have the same issues)
1394 # but the openssl maintainers basically said: "trust us, it just works".
1395 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1396 # and mismaintained ssleay-module doesn't even offer them).
1397 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1398 #
1399 # in short: this is a mess.
1400 #
1401 # note that we do not try to keep the length constant between writes as we are required to do.
1402 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1403 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1404 # have identity issues in that area.
1405 Net::SSLeay::CTX_set_mode ($self->{tls},
1406 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1407 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1408
1409 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1410 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1411
1412 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1413
1414 &_dotls; # need to trigger the initial handshake
1415 $self->start_read; # make sure we actually do read
1416}
1417
1418=item $handle->stoptls
1419
1420Shuts down the SSL connection - this makes a proper EOF handshake by
1421sending a close notify to the other side, but since OpenSSL doesn't
1422support non-blocking shut downs, it is not possible to re-use the stream
1423afterwards.
1424
1425=cut
1426
1427sub stoptls {
1428 my ($self) = @_;
1429
1430 if ($self->{tls}) {
1431 Net::SSLeay::shutdown ($self->{tls});
1432
1433 &_dotls;
1434
1435 # we don't give a shit. no, we do, but we can't. no...
1436 # we, we... have to use openssl :/
1437 &_freetls;
1438 }
1439}
1440
1441sub _freetls {
1442 my ($self) = @_;
1443
1444 return unless $self->{tls};
1445
1446 Net::SSLeay::free (delete $self->{tls});
1447
1448 delete @$self{qw(_rbio _wbio _tls_wbuf)};
1449}
1450
1451sub DESTROY {
565 my $self = shift; 1452 my $self = shift;
566 1453
567 $self->push_read (&_read_line); 1454 &_freetls;
568}
569 1455
570sub unshift_read_line { 1456 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
571 my $self = shift;
572 1457
573 $self->unshift_read (&_read_line); 1458 if ($linger && length $self->{wbuf}) {
1459 my $fh = delete $self->{fh};
1460 my $wbuf = delete $self->{wbuf};
1461
1462 my @linger;
1463
1464 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1465 my $len = syswrite $fh, $wbuf, length $wbuf;
1466
1467 if ($len > 0) {
1468 substr $wbuf, 0, $len, "";
1469 } else {
1470 @linger = (); # end
1471 }
1472 });
1473 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1474 @linger = ();
1475 });
1476 }
1477}
1478
1479=item AnyEvent::Handle::TLS_CTX
1480
1481This function creates and returns the Net::SSLeay::CTX object used by
1482default for TLS mode.
1483
1484The context is created like this:
1485
1486 Net::SSLeay::load_error_strings;
1487 Net::SSLeay::SSLeay_add_ssl_algorithms;
1488 Net::SSLeay::randomize;
1489
1490 my $CTX = Net::SSLeay::CTX_new;
1491
1492 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1493
1494=cut
1495
1496our $TLS_CTX;
1497
1498sub TLS_CTX() {
1499 $TLS_CTX || do {
1500 require Net::SSLeay;
1501
1502 Net::SSLeay::load_error_strings ();
1503 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1504 Net::SSLeay::randomize ();
1505
1506 $TLS_CTX = Net::SSLeay::CTX_new ();
1507
1508 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1509
1510 $TLS_CTX
1511 }
574} 1512}
575 1513
576=back 1514=back
577 1515
1516=head1 SUBCLASSING AnyEvent::Handle
1517
1518In many cases, you might want to subclass AnyEvent::Handle.
1519
1520To make this easier, a given version of AnyEvent::Handle uses these
1521conventions:
1522
1523=over 4
1524
1525=item * all constructor arguments become object members.
1526
1527At least initially, when you pass a C<tls>-argument to the constructor it
1528will end up in C<< $handle->{tls} >>. Those members might be changed or
1529mutated later on (for example C<tls> will hold the TLS connection object).
1530
1531=item * other object member names are prefixed with an C<_>.
1532
1533All object members not explicitly documented (internal use) are prefixed
1534with an underscore character, so the remaining non-C<_>-namespace is free
1535for use for subclasses.
1536
1537=item * all members not documented here and not prefixed with an underscore
1538are free to use in subclasses.
1539
1540Of course, new versions of AnyEvent::Handle may introduce more "public"
1541member variables, but thats just life, at least it is documented.
1542
1543=back
1544
578=head1 AUTHOR 1545=head1 AUTHOR
579 1546
580Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 1547Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
581 1548
582=cut 1549=cut

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