ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent/Handle.pm
Revision: 1.37
Committed: Mon May 26 20:02:22 2008 UTC (16 years ago) by root
Branch: MAIN
Changes since 1.36: +13 -8 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 package AnyEvent::Handle;
2
3 no warnings;
4 use strict;
5
6 use AnyEvent ();
7 use AnyEvent::Util qw(WSAWOULDBLOCK);
8 use Scalar::Util ();
9 use Carp ();
10 use Fcntl ();
11 use Errno qw/EAGAIN EINTR/;
12
13 =head1 NAME
14
15 AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16
17 =cut
18
19 our $VERSION = '0.04';
20
21 =head1 SYNOPSIS
22
23 use AnyEvent;
24 use AnyEvent::Handle;
25
26 my $cv = AnyEvent->condvar;
27
28 my $handle =
29 AnyEvent::Handle->new (
30 fh => \*STDIN,
31 on_eof => sub {
32 $cv->broadcast;
33 },
34 );
35
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;
47
48 =head1 DESCRIPTION
49
50 This module is a helper module to make it easier to do event-based I/O on
51 filehandles. For utility functions for doing non-blocking connects and accepts
52 on sockets see L<AnyEvent::Util>.
53
54 In the following, when the documentation refers to of "bytes" then this
55 means characters. As sysread and syswrite are used for all I/O, their
56 treatment of characters applies to this module as well.
57
58 All callbacks will be invoked with the handle object as their first
59 argument.
60
61 =head1 METHODS
62
63 =over 4
64
65 =item B<new (%args)>
66
67 The constructor supports these arguments (all as key => value pairs).
68
69 =over 4
70
71 =item fh => $filehandle [MANDATORY]
72
73 The filehandle this L<AnyEvent::Handle> object will operate on.
74
75 NOTE: The filehandle will be set to non-blocking (using
76 AnyEvent::Util::fh_nonblocking).
77
78 =item on_eof => $cb->($self)
79
80 Set the callback to be called on EOF.
81
82 While not mandatory, it is highly recommended to set an eof callback,
83 otherwise you might end up with a closed socket while you are still
84 waiting for data.
85
86 =item on_error => $cb->($self)
87
88 This is the fatal error callback, that is called when, well, a fatal error
89 occurs, such as not being able to resolve the hostname, failure to connect
90 or a read error.
91
92 The object will not be in a usable state when this callback has been
93 called.
94
95 On callback entrance, the value of C<$!> contains the operating system
96 error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>).
97
98 The callbakc should throw an exception. If it returns, then
99 AnyEvent::Handle will C<croak> for you.
100
101 While not mandatory, it is I<highly> recommended to set this callback, as
102 you will not be notified of errors otherwise. The default simply calls
103 die.
104
105 =item on_read => $cb->($self)
106
107 This sets the default read callback, which is called when data arrives
108 and no read request is in the queue.
109
110 To access (and remove data from) the read buffer, use the C<< ->rbuf >>
111 method or access the C<$self->{rbuf}> member directly.
112
113 When an EOF condition is detected then AnyEvent::Handle will first try to
114 feed all the remaining data to the queued callbacks and C<on_read> before
115 calling the C<on_eof> callback. If no progress can be made, then a fatal
116 error will be raised (with C<$!> set to C<EPIPE>).
117
118 =item on_drain => $cb->()
119
120 This sets the callback that is called when the write buffer becomes empty
121 (or when the callback is set and the buffer is empty already).
122
123 To append to the write buffer, use the C<< ->push_write >> method.
124
125 =item rbuf_max => <bytes>
126
127 If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
128 when the read buffer ever (strictly) exceeds this size. This is useful to
129 avoid denial-of-service attacks.
130
131 For example, a server accepting connections from untrusted sources should
132 be configured to accept only so-and-so much data that it cannot act on
133 (for example, when expecting a line, an attacker could send an unlimited
134 amount of data without a callback ever being called as long as the line
135 isn't finished).
136
137 =item read_size => <bytes>
138
139 The default read block size (the amount of bytes this module will try to read
140 on each [loop iteration). Default: C<4096>.
141
142 =item low_water_mark => <bytes>
143
144 Sets the amount of bytes (default: C<0>) that make up an "empty" write
145 buffer: If the write reaches this size or gets even samller it is
146 considered empty.
147
148 =item tls => "accept" | "connect" | Net::SSLeay::SSL object
149
150 When this parameter is given, it enables TLS (SSL) mode, that means it
151 will start making tls handshake and will transparently encrypt/decrypt
152 data.
153
154 TLS mode requires Net::SSLeay to be installed (it will be loaded
155 automatically when you try to create a TLS handle).
156
157 For the TLS server side, use C<accept>, and for the TLS client side of a
158 connection, use C<connect> mode.
159
160 You can also provide your own TLS connection object, but you have
161 to make sure that you call either C<Net::SSLeay::set_connect_state>
162 or C<Net::SSLeay::set_accept_state> on it before you pass it to
163 AnyEvent::Handle.
164
165 See the C<starttls> method if you need to start TLs negotiation later.
166
167 =item tls_ctx => $ssl_ctx
168
169 Use the given Net::SSLeay::CTX object to create the new TLS connection
170 (unless a connection object was specified directly). If this parameter is
171 missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172
173 =back
174
175 =cut
176
177 sub new {
178 my $class = shift;
179
180 my $self = bless { @_ }, $class;
181
182 $self->{fh} or Carp::croak "mandatory argument fh is missing";
183
184 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
185
186 if ($self->{tls}) {
187 require Net::SSLeay;
188 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
189 }
190
191 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof};
192 $self->on_error (delete $self->{on_error}) if $self->{on_error};
193 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
194 $self->on_read (delete $self->{on_read} ) if $self->{on_read};
195
196 $self->start_read;
197
198 $self
199 }
200
201 sub _shutdown {
202 my ($self) = @_;
203
204 delete $self->{rw};
205 delete $self->{ww};
206 delete $self->{fh};
207 }
208
209 sub error {
210 my ($self) = @_;
211
212 {
213 local $!;
214 $self->_shutdown;
215 }
216
217 $self->{on_error}($self)
218 if $self->{on_error};
219
220 Carp::croak "AnyEvent::Handle uncaught fatal error: $!";
221 }
222
223 =item $fh = $handle->fh
224
225 This method returns the file handle of the L<AnyEvent::Handle> object.
226
227 =cut
228
229 sub fh { $_[0]->{fh} }
230
231 =item $handle->on_error ($cb)
232
233 Replace the current C<on_error> callback (see the C<on_error> constructor argument).
234
235 =cut
236
237 sub on_error {
238 $_[0]{on_error} = $_[1];
239 }
240
241 =item $handle->on_eof ($cb)
242
243 Replace the current C<on_eof> callback (see the C<on_eof> constructor argument).
244
245 =cut
246
247 sub on_eof {
248 $_[0]{on_eof} = $_[1];
249 }
250
251 #############################################################################
252
253 =back
254
255 =head2 WRITE QUEUE
256
257 AnyEvent::Handle manages two queues per handle, one for writing and one
258 for reading.
259
260 The write queue is very simple: you can add data to its end, and
261 AnyEvent::Handle will automatically try to get rid of it for you.
262
263 When data could be written and the write buffer is shorter then the low
264 water mark, the C<on_drain> callback will be invoked.
265
266 =over 4
267
268 =item $handle->on_drain ($cb)
269
270 Sets the C<on_drain> callback or clears it (see the description of
271 C<on_drain> in the constructor).
272
273 =cut
274
275 sub on_drain {
276 my ($self, $cb) = @_;
277
278 $self->{on_drain} = $cb;
279
280 $cb->($self)
281 if $cb && $self->{low_water_mark} >= length $self->{wbuf};
282 }
283
284 =item $handle->push_write ($data)
285
286 Queues the given scalar to be written. You can push as much data as you
287 want (only limited by the available memory), as C<AnyEvent::Handle>
288 buffers it independently of the kernel.
289
290 =cut
291
292 sub _drain_wbuf {
293 my ($self) = @_;
294
295 if (!$self->{ww} && length $self->{wbuf}) {
296
297 Scalar::Util::weaken $self;
298
299 my $cb = sub {
300 my $len = syswrite $self->{fh}, $self->{wbuf};
301
302 if ($len >= 0) {
303 substr $self->{wbuf}, 0, $len, "";
304
305 $self->{on_drain}($self)
306 if $self->{low_water_mark} >= length $self->{wbuf}
307 && $self->{on_drain};
308
309 delete $self->{ww} unless length $self->{wbuf};
310 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) {
311 $self->error;
312 }
313 };
314
315 # try to write data immediately
316 $cb->();
317
318 # if still data left in wbuf, we need to poll
319 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
320 if length $self->{wbuf};
321 };
322 }
323
324 our %WH;
325
326 sub register_write_type($$) {
327 $WH{$_[0]} = $_[1];
328 }
329
330 sub push_write {
331 my $self = shift;
332
333 if (@_ > 1) {
334 my $type = shift;
335
336 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
337 ->($self, @_);
338 }
339
340 if ($self->{filter_w}) {
341 $self->{filter_w}->($self, \$_[0]);
342 } else {
343 $self->{wbuf} .= $_[0];
344 $self->_drain_wbuf;
345 }
346 }
347
348 =item $handle->push_write (type => @args)
349
350 =item $handle->unshift_write (type => @args)
351
352 Instead of formatting your data yourself, you can also let this module do
353 the job by specifying a type and type-specific arguments.
354
355 Predefined types are (if you have ideas for additional types, feel free to
356 drop by and tell us):
357
358 =over 4
359
360 =item netstring => $string
361
362 Formats the given value as netstring
363 (http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
364
365 =back
366
367 =cut
368
369 register_write_type netstring => sub {
370 my ($self, $string) = @_;
371
372 sprintf "%d:%s,", (length $string), $string
373 };
374
375 =item AnyEvent::Handle::register_write_type type => $coderef->($self, @args)
376
377 This function (not method) lets you add your own types to C<push_write>.
378 Whenever the given C<type> is used, C<push_write> will invoke the code
379 reference with the handle object and the remaining arguments.
380
381 The code reference is supposed to return a single octet string that will
382 be appended to the write buffer.
383
384 Note that this is a function, and all types registered this way will be
385 global, so try to use unique names.
386
387 =cut
388
389 #############################################################################
390
391 =back
392
393 =head2 READ QUEUE
394
395 AnyEvent::Handle manages two queues per handle, one for writing and one
396 for reading.
397
398 The read queue is more complex than the write queue. It can be used in two
399 ways, the "simple" way, using only C<on_read> and the "complex" way, using
400 a queue.
401
402 In the simple case, you just install an C<on_read> callback and whenever
403 new data arrives, it will be called. You can then remove some data (if
404 enough is there) from the read buffer (C<< $handle->rbuf >>) if you want
405 or not.
406
407 In the more complex case, you want to queue multiple callbacks. In this
408 case, AnyEvent::Handle will call the first queued callback each time new
409 data arrives and removes it when it has done its job (see C<push_read>,
410 below).
411
412 This way you can, for example, push three line-reads, followed by reading
413 a chunk of data, and AnyEvent::Handle will execute them in order.
414
415 Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
416 the specified number of bytes which give an XML datagram.
417
418 # in the default state, expect some header bytes
419 $handle->on_read (sub {
420 # some data is here, now queue the length-header-read (4 octets)
421 shift->unshift_read_chunk (4, sub {
422 # header arrived, decode
423 my $len = unpack "N", $_[1];
424
425 # now read the payload
426 shift->unshift_read_chunk ($len, sub {
427 my $xml = $_[1];
428 # handle xml
429 });
430 });
431 });
432
433 Example 2: Implement a client for a protocol that replies either with
434 "OK" and another line or "ERROR" for one request, and 64 bytes for the
435 second request. Due tot he availability of a full queue, we can just
436 pipeline sending both requests and manipulate the queue as necessary in
437 the callbacks:
438
439 # request one
440 $handle->push_write ("request 1\015\012");
441
442 # we expect "ERROR" or "OK" as response, so push a line read
443 $handle->push_read_line (sub {
444 # if we got an "OK", we have to _prepend_ another line,
445 # so it will be read before the second request reads its 64 bytes
446 # which are already in the queue when this callback is called
447 # we don't do this in case we got an error
448 if ($_[1] eq "OK") {
449 $_[0]->unshift_read_line (sub {
450 my $response = $_[1];
451 ...
452 });
453 }
454 });
455
456 # request two
457 $handle->push_write ("request 2\015\012");
458
459 # simply read 64 bytes, always
460 $handle->push_read_chunk (64, sub {
461 my $response = $_[1];
462 ...
463 });
464
465 =over 4
466
467 =cut
468
469 sub _drain_rbuf {
470 my ($self) = @_;
471
472 if (
473 defined $self->{rbuf_max}
474 && $self->{rbuf_max} < length $self->{rbuf}
475 ) {
476 $! = &Errno::ENOSPC;
477 $self->error;
478 }
479
480 return if $self->{in_drain};
481 local $self->{in_drain} = 1;
482
483 while (my $len = length $self->{rbuf}) {
484 no strict 'refs';
485 if (my $cb = shift @{ $self->{queue} }) {
486 unless ($cb->($self)) {
487 if ($self->{eof}) {
488 # no progress can be made (not enough data and no data forthcoming)
489 $! = &Errno::EPIPE;
490 $self->error;
491 }
492
493 unshift @{ $self->{queue} }, $cb;
494 return;
495 }
496 } elsif ($self->{on_read}) {
497 $self->{on_read}($self);
498
499 if (
500 $self->{eof} # if no further data will arrive
501 && $len == length $self->{rbuf} # and no data has been consumed
502 && !@{ $self->{queue} } # and the queue is still empty
503 && $self->{on_read} # and we still want to read data
504 ) {
505 # then no progress can be made
506 $! = &Errno::EPIPE;
507 $self->error;
508 }
509 } else {
510 # read side becomes idle
511 delete $self->{rw};
512 return;
513 }
514 }
515
516 if ($self->{eof}) {
517 $self->_shutdown;
518 $self->{on_eof}($self)
519 if $self->{on_eof};
520 }
521 }
522
523 =item $handle->on_read ($cb)
524
525 This replaces the currently set C<on_read> callback, or clears it (when
526 the new callback is C<undef>). See the description of C<on_read> in the
527 constructor.
528
529 =cut
530
531 sub on_read {
532 my ($self, $cb) = @_;
533
534 $self->{on_read} = $cb;
535 }
536
537 =item $handle->rbuf
538
539 Returns the read buffer (as a modifiable lvalue).
540
541 You can access the read buffer directly as the C<< ->{rbuf} >> member, if
542 you want.
543
544 NOTE: The read buffer should only be used or modified if the C<on_read>,
545 C<push_read> or C<unshift_read> methods are used. The other read methods
546 automatically manage the read buffer.
547
548 =cut
549
550 sub rbuf : lvalue {
551 $_[0]{rbuf}
552 }
553
554 =item $handle->push_read ($cb)
555
556 =item $handle->unshift_read ($cb)
557
558 Append the given callback to the end of the queue (C<push_read>) or
559 prepend it (C<unshift_read>).
560
561 The callback is called each time some additional read data arrives.
562
563 It must check whether enough data is in the read buffer already.
564
565 If not enough data is available, it must return the empty list or a false
566 value, in which case it will be called repeatedly until enough data is
567 available (or an error condition is detected).
568
569 If enough data was available, then the callback must remove all data it is
570 interested in (which can be none at all) and return a true value. After returning
571 true, it will be removed from the queue.
572
573 =cut
574
575 our %RH;
576
577 sub register_read_type($$) {
578 $RH{$_[0]} = $_[1];
579 }
580
581 sub push_read {
582 my $self = shift;
583 my $cb = pop;
584
585 if (@_) {
586 my $type = shift;
587
588 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
589 ->($self, $cb, @_);
590 }
591
592 push @{ $self->{queue} }, $cb;
593 $self->_drain_rbuf;
594 }
595
596 sub unshift_read {
597 my $self = shift;
598 my $cb = pop;
599
600 if (@_) {
601 my $type = shift;
602
603 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
604 ->($self, $cb, @_);
605 }
606
607
608 unshift @{ $self->{queue} }, $cb;
609 $self->_drain_rbuf;
610 }
611
612 =item $handle->push_read (type => @args, $cb)
613
614 =item $handle->unshift_read (type => @args, $cb)
615
616 Instead of providing a callback that parses the data itself you can chose
617 between a number of predefined parsing formats, for chunks of data, lines
618 etc.
619
620 Predefined types are (if you have ideas for additional types, feel free to
621 drop by and tell us):
622
623 =over 4
624
625 =item chunk => $octets, $cb->($self, $data)
626
627 Invoke the callback only once C<$octets> bytes have been read. Pass the
628 data read to the callback. The callback will never be called with less
629 data.
630
631 Example: read 2 bytes.
632
633 $handle->push_read (chunk => 2, sub {
634 warn "yay ", unpack "H*", $_[1];
635 });
636
637 =cut
638
639 register_read_type chunk => sub {
640 my ($self, $cb, $len) = @_;
641
642 sub {
643 $len <= length $_[0]{rbuf} or return;
644 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
645 1
646 }
647 };
648
649 # compatibility with older API
650 sub push_read_chunk {
651 $_[0]->push_read (chunk => $_[1], $_[2]);
652 }
653
654 sub unshift_read_chunk {
655 $_[0]->unshift_read (chunk => $_[1], $_[2]);
656 }
657
658 =item line => [$eol, ]$cb->($self, $line, $eol)
659
660 The callback will be called only once a full line (including the end of
661 line marker, C<$eol>) has been read. This line (excluding the end of line
662 marker) will be passed to the callback as second argument (C<$line>), and
663 the end of line marker as the third argument (C<$eol>).
664
665 The end of line marker, C<$eol>, can be either a string, in which case it
666 will be interpreted as a fixed record end marker, or it can be a regex
667 object (e.g. created by C<qr>), in which case it is interpreted as a
668 regular expression.
669
670 The end of line marker argument C<$eol> is optional, if it is missing (NOT
671 undef), then C<qr|\015?\012|> is used (which is good for most internet
672 protocols).
673
674 Partial lines at the end of the stream will never be returned, as they are
675 not marked by the end of line marker.
676
677 =cut
678
679 register_read_type line => sub {
680 my ($self, $cb, $eol) = @_;
681
682 $eol = qr|(\015?\012)| if @_ < 3;
683 $eol = quotemeta $eol unless ref $eol;
684 $eol = qr|^(.*?)($eol)|s;
685
686 sub {
687 $_[0]{rbuf} =~ s/$eol// or return;
688
689 $cb->($_[0], $1, $2);
690 1
691 }
692 };
693
694 # compatibility with older API
695 sub push_read_line {
696 my $self = shift;
697 $self->push_read (line => @_);
698 }
699
700 sub unshift_read_line {
701 my $self = shift;
702 $self->unshift_read (line => @_);
703 }
704
705 =item netstring => $cb->($string)
706
707 A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
708
709 Throws an error with C<$!> set to EBADMSG on format violations.
710
711 =cut
712
713 register_read_type netstring => sub {
714 my ($self, $cb) = @_;
715
716 sub {
717 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
718 if ($_[0]{rbuf} =~ /[^0-9]/) {
719 $! = &Errno::EBADMSG;
720 $self->error;
721 }
722 return;
723 }
724
725 my $len = $1;
726
727 $self->unshift_read (chunk => $len, sub {
728 my $string = $_[1];
729 $_[0]->unshift_read (chunk => 1, sub {
730 if ($_[1] eq ",") {
731 $cb->($_[0], $string);
732 } else {
733 $! = &Errno::EBADMSG;
734 $self->error;
735 }
736 });
737 });
738
739 1
740 }
741 };
742
743 =item regex => $accept[, $reject[, $skip], $cb->($data)
744
745 Makes a regex match against the regex object C<$accept> and returns
746 everything up to and including the match.
747
748 Example: read a single line terminated by '\n'.
749
750 $handle->push_read (regex => qr<\n>, sub { ... });
751
752 If C<$reject> is given and not undef, then it determines when the data is
753 to be rejected: it is matched against the data when the C<$accept> regex
754 does not match and generates an C<EBADMSG> error when it matches. This is
755 useful to quickly reject wrong data (to avoid waiting for a timeout or a
756 receive buffer overflow).
757
758 Example: expect a single decimal number followed by whitespace, reject
759 anything else (not the use of an anchor).
760
761 $handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
762
763 If C<$skip> is given and not C<undef>, then it will be matched against
764 the receive buffer when neither C<$accept> nor C<$reject> match,
765 and everything preceding and including the match will be accepted
766 unconditionally. This is useful to skip large amounts of data that you
767 know cannot be matched, so that the C<$accept> or C<$reject> regex do not
768 have to start matching from the beginning. This is purely an optimisation
769 and is usually worth only when you expect more than a few kilobytes.
770
771 Example: expect a http header, which ends at C<\015\012\015\012>. Since we
772 expect the header to be very large (it isn't in practise, but...), we use
773 a skip regex to skip initial portions. The skip regex is tricky in that
774 it only accepts something not ending in either \015 or \012, as these are
775 required for the accept regex.
776
777 $handle->push_read (regex =>
778 qr<\015\012\015\012>,
779 undef, # no reject
780 qr<^.*[^\015\012]>,
781 sub { ... });
782
783 =cut
784
785 register_read_type regex => sub {
786 my ($self, $cb, $accept, $reject, $skip) = @_;
787
788 my $data;
789 my $rbuf = \$self->{rbuf};
790
791 sub {
792 # accept
793 if ($$rbuf =~ $accept) {
794 $data .= substr $$rbuf, 0, $+[0], "";
795 $cb->($self, $data);
796 return 1;
797 }
798
799 # reject
800 if ($reject && $$rbuf =~ $reject) {
801 $! = &Errno::EBADMSG;
802 $self->error;
803 }
804
805 # skip
806 if ($skip && $$rbuf =~ $skip) {
807 $data .= substr $$rbuf, 0, $+[0], "";
808 }
809
810 ()
811 }
812 };
813
814 =back
815
816 =item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args)
817
818 This function (not method) lets you add your own types to C<push_read>.
819
820 Whenever the given C<type> is used, C<push_read> will invoke the code
821 reference with the handle object, the callback and the remaining
822 arguments.
823
824 The code reference is supposed to return a callback (usually a closure)
825 that works as a plain read callback (see C<< ->push_read ($cb) >>).
826
827 It should invoke the passed callback when it is done reading (remember to
828 pass C<$self> as first argument as all other callbacks do that).
829
830 Note that this is a function, and all types registered this way will be
831 global, so try to use unique names.
832
833 For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
834 search for C<register_read_type>)).
835
836 =item $handle->stop_read
837
838 =item $handle->start_read
839
840 In rare cases you actually do not want to read anything from the
841 socket. In this case you can call C<stop_read>. Neither C<on_read> no
842 any queued callbacks will be executed then. To start reading again, call
843 C<start_read>.
844
845 =cut
846
847 sub stop_read {
848 my ($self) = @_;
849
850 delete $self->{rw};
851 }
852
853 sub start_read {
854 my ($self) = @_;
855
856 unless ($self->{rw} || $self->{eof}) {
857 Scalar::Util::weaken $self;
858
859 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
860 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
861 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
862
863 if ($len > 0) {
864 $self->{filter_r}
865 ? $self->{filter_r}->($self, $rbuf)
866 : $self->_drain_rbuf;
867
868 } elsif (defined $len) {
869 delete $self->{rw};
870 $self->{eof} = 1;
871 $self->_drain_rbuf;
872
873 } elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) {
874 return $self->error;
875 }
876 });
877 }
878 }
879
880 sub _dotls {
881 my ($self) = @_;
882
883 if (length $self->{tls_wbuf}) {
884 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf})) > 0) {
885 substr $self->{tls_wbuf}, 0, $len, "";
886 }
887 }
888
889 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) {
890 $self->{wbuf} .= $buf;
891 $self->_drain_wbuf;
892 }
893
894 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
895 $self->{rbuf} .= $buf;
896 $self->_drain_rbuf;
897 }
898
899 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
900
901 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
902 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
903 $self->error;
904 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
905 $! = &Errno::EIO;
906 $self->error;
907 }
908
909 # all others are fine for our purposes
910 }
911 }
912
913 =item $handle->starttls ($tls[, $tls_ctx])
914
915 Instead of starting TLS negotiation immediately when the AnyEvent::Handle
916 object is created, you can also do that at a later time by calling
917 C<starttls>.
918
919 The first argument is the same as the C<tls> constructor argument (either
920 C<"connect">, C<"accept"> or an existing Net::SSLeay object).
921
922 The second argument is the optional C<Net::SSLeay::CTX> object that is
923 used when AnyEvent::Handle has to create its own TLS connection object.
924
925 =cut
926
927 # TODO: maybe document...
928 sub starttls {
929 my ($self, $ssl, $ctx) = @_;
930
931 $self->stoptls;
932
933 if ($ssl eq "accept") {
934 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
935 Net::SSLeay::set_accept_state ($ssl);
936 } elsif ($ssl eq "connect") {
937 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
938 Net::SSLeay::set_connect_state ($ssl);
939 }
940
941 $self->{tls} = $ssl;
942
943 # basically, this is deep magic (because SSL_read should have the same issues)
944 # but the openssl maintainers basically said: "trust us, it just works".
945 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
946 # and mismaintained ssleay-module doesn't even offer them).
947 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
948 Net::SSLeay::CTX_set_mode ($self->{tls},
949 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
950 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
951
952 $self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
953 $self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
954
955 Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio});
956
957 $self->{filter_w} = sub {
958 $_[0]{tls_wbuf} .= ${$_[1]};
959 &_dotls;
960 };
961 $self->{filter_r} = sub {
962 Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
963 &_dotls;
964 };
965 }
966
967 =item $handle->stoptls
968
969 Destroys the SSL connection, if any. Partial read or write data will be
970 lost.
971
972 =cut
973
974 sub stoptls {
975 my ($self) = @_;
976
977 Net::SSLeay::free (delete $self->{tls}) if $self->{tls};
978 delete $self->{tls_rbio};
979 delete $self->{tls_wbio};
980 delete $self->{tls_wbuf};
981 delete $self->{filter_r};
982 delete $self->{filter_w};
983 }
984
985 sub DESTROY {
986 my $self = shift;
987
988 $self->stoptls;
989 }
990
991 =item AnyEvent::Handle::TLS_CTX
992
993 This function creates and returns the Net::SSLeay::CTX object used by
994 default for TLS mode.
995
996 The context is created like this:
997
998 Net::SSLeay::load_error_strings;
999 Net::SSLeay::SSLeay_add_ssl_algorithms;
1000 Net::SSLeay::randomize;
1001
1002 my $CTX = Net::SSLeay::CTX_new;
1003
1004 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1005
1006 =cut
1007
1008 our $TLS_CTX;
1009
1010 sub TLS_CTX() {
1011 $TLS_CTX || do {
1012 require Net::SSLeay;
1013
1014 Net::SSLeay::load_error_strings ();
1015 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1016 Net::SSLeay::randomize ();
1017
1018 $TLS_CTX = Net::SSLeay::CTX_new ();
1019
1020 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1021
1022 $TLS_CTX
1023 }
1024 }
1025
1026 =back
1027
1028 =head1 AUTHOR
1029
1030 Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1031
1032 =cut
1033
1034 1; # End of AnyEvent::Handle