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Revision 1.202 by root, Sat Oct 16 02:01:54 2010 UTC vs.
Revision 1.253 by root, Fri Feb 7 15:06:01 2020 UTC

11 11
12 my $hdl; $hdl = new AnyEvent::Handle 12 my $hdl; $hdl = new AnyEvent::Handle
13 fh => \*STDIN, 13 fh => \*STDIN,
14 on_error => sub { 14 on_error => sub {
15 my ($hdl, $fatal, $msg) = @_; 15 my ($hdl, $fatal, $msg) = @_;
16 warn "got error $msg\n"; 16 AE::log error => $msg;
17 $hdl->destroy; 17 $hdl->destroy;
18 $cv->send; 18 $cv->send;
19 }; 19 };
20 20
21 # send some request line 21 # send some request line
22 $hdl->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
23 23
24 # read the response line 24 # read the response line
25 $hdl->push_read (line => sub { 25 $hdl->push_read (line => sub {
26 my ($hdl, $line) = @_; 26 my ($hdl, $line) = @_;
27 warn "got line <$line>\n"; 27 say "got line <$line>";
28 $cv->send; 28 $cv->send;
29 }); 29 });
30 30
31 $cv->recv; 31 $cv->recv;
32 32
33=head1 DESCRIPTION 33=head1 DESCRIPTION
34 34
35This is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O
36stream-based filehandles (sockets, pipes, and other stream things). 36on stream-based filehandles (sockets, pipes, and other stream
37things). Specifically, it doesn't work as expected on files, packet-based
38sockets or similar things.
37 39
38The L<AnyEvent::Intro> tutorial contains some well-documented 40The L<AnyEvent::Intro> tutorial contains some well-documented
39AnyEvent::Handle examples. 41AnyEvent::Handle examples.
40 42
41In the following, where the documentation refers to "bytes", it means 43In the following, where the documentation refers to "bytes", it means
53package AnyEvent::Handle; 55package AnyEvent::Handle;
54 56
55use Scalar::Util (); 57use Scalar::Util ();
56use List::Util (); 58use List::Util ();
57use Carp (); 59use Carp ();
58use Errno qw(EAGAIN EINTR); 60use Errno qw(EAGAIN EWOULDBLOCK EINTR);
59 61
60use AnyEvent (); BEGIN { AnyEvent::common_sense } 62use AnyEvent (); BEGIN { AnyEvent::common_sense }
61use AnyEvent::Util qw(WSAEWOULDBLOCK); 63use AnyEvent::Util qw(WSAEWOULDBLOCK);
62 64
63our $VERSION = $AnyEvent::VERSION; 65our $VERSION = $AnyEvent::VERSION;
75 } 77 }
76 78
77 \&$func 79 \&$func
78} 80}
79 81
82sub MAX_READ_SIZE() { 131072 }
83
80=head1 METHODS 84=head1 METHODS
81 85
82=over 4 86=over 4
83 87
84=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value... 88=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
89 93
90=item fh => $filehandle [C<fh> or C<connect> MANDATORY] 94=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
91 95
92The filehandle this L<AnyEvent::Handle> object will operate on. 96The filehandle this L<AnyEvent::Handle> object will operate on.
93NOTE: The filehandle will be set to non-blocking mode (using 97NOTE: The filehandle will be set to non-blocking mode (using
94C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in 98C<AnyEvent::fh_unblock>) by the constructor and needs to stay in
95that mode. 99that mode.
96 100
97=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY] 101=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
98 102
99Try to connect to the specified host and service (port), using 103Try to connect to the specified host and service (port), using
112=over 4 116=over 4
113 117
114=item on_prepare => $cb->($handle) 118=item on_prepare => $cb->($handle)
115 119
116This (rarely used) callback is called before a new connection is 120This (rarely used) callback is called before a new connection is
117attempted, but after the file handle has been created. It could be used to 121attempted, but after the file handle has been created (you can access that
122file handle via C<< $handle->{fh} >>). It could be used to prepare the
118prepare the file handle with parameters required for the actual connect 123file handle with parameters required for the actual connect (as opposed to
119(as opposed to settings that can be changed when the connection is already 124settings that can be changed when the connection is already established).
120established).
121 125
122The return value of this callback should be the connect timeout value in 126The return value of this callback should be the connect timeout value in
123seconds (or C<0>, or C<undef>, or the empty list, to indicate that the 127seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
124default timeout is to be used). 128default timeout is to be used).
125 129
126=item on_connect => $cb->($handle, $host, $port, $retry->()) 130=item on_connect => $cb->($handle, $host, $port, $retry->())
127 131
128This callback is called when a connection has been successfully established. 132This callback is called when a connection has been successfully established.
129 133
130The peer's numeric host and port (the socket peername) are passed as 134The peer's numeric host and port (the socket peername) are passed as
131parameters, together with a retry callback. 135parameters, together with a retry callback. At the time it is called the
136read and write queues, EOF status, TLS status and similar properties of
137the handle will have been reset.
132 138
133If, for some reason, the handle is not acceptable, calling C<$retry> 139If, for some reason, the handle is not acceptable, calling C<$retry> will
134will continue with the next connection target (in case of multi-homed 140continue with the next connection target (in case of multi-homed hosts or
135hosts or SRV records there can be multiple connection endpoints). At the 141SRV records there can be multiple connection endpoints). The C<$retry>
136time it is called the read and write queues, eof status, tls status and 142callback can be invoked after the connect callback returns, i.e. one can
137similar properties of the handle will have been reset. 143start a handshake and then decide to retry with the next host if the
144handshake fails.
138 145
139In most cases, you should ignore the C<$retry> parameter. 146In most cases, you should ignore the C<$retry> parameter.
140 147
141=item on_connect_error => $cb->($handle, $message) 148=item on_connect_error => $cb->($handle, $message)
142 149
157 164
158Some errors are fatal (which is indicated by C<$fatal> being true). On 165Some errors are fatal (which is indicated by C<$fatal> being true). On
159fatal errors the handle object will be destroyed (by a call to C<< -> 166fatal errors the handle object will be destroyed (by a call to C<< ->
160destroy >>) after invoking the error callback (which means you are free to 167destroy >>) after invoking the error callback (which means you are free to
161examine the handle object). Examples of fatal errors are an EOF condition 168examine the handle object). Examples of fatal errors are an EOF condition
162with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 169with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
163cases where the other side can close the connection at will, it is 170cases where the other side can close the connection at will, it is
164often easiest to not report C<EPIPE> errors in this callback. 171often easiest to not report C<EPIPE> errors in this callback.
165 172
166AnyEvent::Handle tries to find an appropriate error code for you to check 173AnyEvent::Handle tries to find an appropriate error code for you to check
167against, but in some cases (TLS errors), this does not work well. It is 174against, but in some cases (TLS errors), this does not work well.
168recommended to always output the C<$message> argument in human-readable 175
169error messages (it's usually the same as C<"$!">). 176If you report the error to the user, it is recommended to always output
177the C<$message> argument in human-readable error messages (you don't need
178to report C<"$!"> if you report C<$message>).
179
180If you want to react programmatically to the error, then looking at C<$!>
181and comparing it against some of the documented C<Errno> values is usually
182better than looking at the C<$message>.
170 183
171Non-fatal errors can be retried by returning, but it is recommended 184Non-fatal errors can be retried by returning, but it is recommended
172to simply ignore this parameter and instead abondon the handle object 185to simply ignore this parameter and instead abondon the handle object
173when this callback is invoked. Examples of non-fatal errors are timeouts 186when this callback is invoked. Examples of non-fatal errors are timeouts
174C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 187C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
222If an EOF condition has been detected but no C<on_eof> callback has been 235If an EOF condition has been detected but no C<on_eof> callback has been
223set, then a fatal error will be raised with C<$!> set to <0>. 236set, then a fatal error will be raised with C<$!> set to <0>.
224 237
225=item on_drain => $cb->($handle) 238=item on_drain => $cb->($handle)
226 239
227This sets the callback that is called when the write buffer becomes empty 240This sets the callback that is called once when the write buffer becomes
228(or immediately if the buffer is empty already). 241empty (and immediately when the handle object is created).
229 242
230To append to the write buffer, use the C<< ->push_write >> method. 243To append to the write buffer, use the C<< ->push_write >> method.
231 244
232This callback is useful when you don't want to put all of your write data 245This callback is useful when you don't want to put all of your write data
233into the queue at once, for example, when you want to write the contents 246into the queue at once, for example, when you want to write the contents
245many seconds pass without a successful read or write on the underlying 258many seconds pass without a successful read or write on the underlying
246file handle (or a call to C<timeout_reset>), the C<on_timeout> callback 259file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
247will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> 260will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
248error will be raised). 261error will be raised).
249 262
250There are three variants of the timeouts that work independently 263There are three variants of the timeouts that work independently of each
251of each other, for both read and write, just read, and just write: 264other, for both read and write (triggered when nothing was read I<OR>
265written), just read (triggered when nothing was read), and just write:
252C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 266C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
253C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 267C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
254C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 268C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
255 269
256Note that timeout processing is active even when you do not have 270Note that timeout processing is active even when you do not have any
257any outstanding read or write requests: If you plan to keep the connection 271outstanding read or write requests: If you plan to keep the connection
258idle then you should disable the timeout temporarily or ignore the timeout 272idle then you should disable the timeout temporarily or ignore the
259in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 273timeout in the corresponding C<on_timeout> callback, in which case
260restart the timeout. 274AnyEvent::Handle will simply restart the timeout.
261 275
262Zero (the default) disables this timeout. 276Zero (the default) disables the corresponding timeout.
263 277
264=item on_timeout => $cb->($handle) 278=item on_timeout => $cb->($handle)
279
280=item on_rtimeout => $cb->($handle)
281
282=item on_wtimeout => $cb->($handle)
265 283
266Called whenever the inactivity timeout passes. If you return from this 284Called whenever the inactivity timeout passes. If you return from this
267callback, then the timeout will be reset as if some activity had happened, 285callback, then the timeout will be reset as if some activity had happened,
268so this condition is not fatal in any way. 286so this condition is not fatal in any way.
269 287
276For example, a server accepting connections from untrusted sources should 294For example, a server accepting connections from untrusted sources should
277be configured to accept only so-and-so much data that it cannot act on 295be configured to accept only so-and-so much data that it cannot act on
278(for example, when expecting a line, an attacker could send an unlimited 296(for example, when expecting a line, an attacker could send an unlimited
279amount of data without a callback ever being called as long as the line 297amount of data without a callback ever being called as long as the line
280isn't finished). 298isn't finished).
299
300=item wbuf_max => <bytes>
301
302If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
303when the write buffer ever (strictly) exceeds this size. This is useful to
304avoid some forms of denial-of-service attacks.
305
306Although the units of this parameter is bytes, this is the I<raw> number
307of bytes not yet accepted by the kernel. This can make a difference when
308you e.g. use TLS, as TLS typically makes your write data larger (but it
309can also make it smaller due to compression).
310
311As an example of when this limit is useful, take a chat server that sends
312chat messages to a client. If the client does not read those in a timely
313manner then the send buffer in the server would grow unbounded.
281 314
282=item autocork => <boolean> 315=item autocork => <boolean>
283 316
284When disabled (the default), C<push_write> will try to immediately 317When disabled (the default), C<push_write> will try to immediately
285write the data to the handle if possible. This avoids having to register 318write the data to the handle if possible. This avoids having to register
337already have occured on BSD systems), but at least it will protect you 370already have occured on BSD systems), but at least it will protect you
338from most attacks. 371from most attacks.
339 372
340=item read_size => <bytes> 373=item read_size => <bytes>
341 374
342The default read block size (the number of bytes this module will 375The initial read block size, the number of bytes this module will try
343try to read during each loop iteration, which affects memory 376to read during each loop iteration. Each handle object will consume
344requirements). Default: C<8192>. 377at least this amount of memory for the read buffer as well, so when
378handling many connections watch out for memory requirements). See also
379C<max_read_size>. Default: C<2048>.
380
381=item max_read_size => <bytes>
382
383The maximum read buffer size used by the dynamic adjustment
384algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
385one go it will double C<read_size> up to the maximum given by this
386option. Default: C<131072> or C<read_size>, whichever is higher.
345 387
346=item low_water_mark => <bytes> 388=item low_water_mark => <bytes>
347 389
348Sets the number of bytes (default: C<0>) that make up an "empty" write 390Sets the number of bytes (default: C<0>) that make up an "empty" write
349buffer: If the buffer reaches this size or gets even samller it is 391buffer: If the buffer reaches this size or gets even samller it is
386appropriate error message. 428appropriate error message.
387 429
388TLS mode requires Net::SSLeay to be installed (it will be loaded 430TLS mode requires Net::SSLeay to be installed (it will be loaded
389automatically when you try to create a TLS handle): this module doesn't 431automatically when you try to create a TLS handle): this module doesn't
390have a dependency on that module, so if your module requires it, you have 432have a dependency on that module, so if your module requires it, you have
391to add the dependency yourself. 433to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
434old, you get an C<EPROTO> error.
392 435
393Unlike TCP, TLS has a server and client side: for the TLS server side, use 436Unlike TCP, TLS has a server and client side: for the TLS server side, use
394C<accept>, and for the TLS client side of a connection, use C<connect> 437C<accept>, and for the TLS client side of a connection, use C<connect>
395mode. 438mode.
396 439
412Use the C<< ->starttls >> method if you need to start TLS negotiation later. 455Use the C<< ->starttls >> method if you need to start TLS negotiation later.
413 456
414=item tls_ctx => $anyevent_tls 457=item tls_ctx => $anyevent_tls
415 458
416Use the given C<AnyEvent::TLS> object to create the new TLS connection 459Use the given C<AnyEvent::TLS> object to create the new TLS connection
417(unless a connection object was specified directly). If this parameter is 460(unless a connection object was specified directly). If this
418missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 461parameter is missing (or C<undef>), then AnyEvent::Handle will use
462C<AnyEvent::Handle::TLS_CTX>.
419 463
420Instead of an object, you can also specify a hash reference with C<< key 464Instead of an object, you can also specify a hash reference with C<< key
421=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 465=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
422new TLS context object. 466new TLS context object.
423 467
451callback. 495callback.
452 496
453This callback will only be called on TLS shutdowns, not when the 497This callback will only be called on TLS shutdowns, not when the
454underlying handle signals EOF. 498underlying handle signals EOF.
455 499
456=item json => JSON or JSON::XS object 500=item json => L<JSON>, L<JSON::PP> or L<JSON::XS> object
457 501
458This is the json coder object used by the C<json> read and write types. 502This is the json coder object used by the C<json> read and write types.
459 503
460If you don't supply it, then AnyEvent::Handle will create and use a 504If you don't supply it, then AnyEvent::Handle will create and use a
461suitable one (on demand), which will write and expect UTF-8 encoded JSON 505suitable one (on demand), which will write and expect UTF-8 encoded
506JSON texts (either using L<JSON::XS> or L<JSON>). The written texts are
507guaranteed not to contain any newline character.
508
509For security reasons, this encoder will likely I<not> handle numbers and
510strings, only arrays and objects/hashes. The reason is that originally
511JSON was self-delimited, but Dougles Crockford thought it was a splendid
512idea to redefine JSON incompatibly, so this is no longer true.
513
514For protocols that used back-to-back JSON texts, this might lead to
515run-ins, where two or more JSON texts will be interpreted as one JSON
462texts. 516text.
463 517
518For this reason, if the default encoder uses L<JSON::XS>, it will default
519to not allowing anything but arrays and objects/hashes, at least for the
520forseeable future (it will change at some point). This might or might not
521be true for the L<JSON> module, so this might cause a security issue.
522
523If you depend on either behaviour, you should create your own json object
524and pass it in explicitly.
525
526=item cbor => L<CBOR::XS> object
527
528This is the cbor coder object used by the C<cbor> read and write types.
529
530If you don't supply it, then AnyEvent::Handle will create and use a
531suitable one (on demand), which will write CBOR without using extensions,
532if possible.
533
464Note that you are responsible to depend on the JSON module if you want to 534Note that you are responsible to depend on the L<CBOR::XS> module if you
465use this functionality, as AnyEvent does not have a dependency itself. 535want to use this functionality, as AnyEvent does not have a dependency on
536it itself.
466 537
467=back 538=back
468 539
469=cut 540=cut
470 541
492 $self->{connect}[0], 563 $self->{connect}[0],
493 $self->{connect}[1], 564 $self->{connect}[1],
494 sub { 565 sub {
495 my ($fh, $host, $port, $retry) = @_; 566 my ($fh, $host, $port, $retry) = @_;
496 567
568 delete $self->{_connect}; # no longer needed
569
497 if ($fh) { 570 if ($fh) {
498 $self->{fh} = $fh; 571 $self->{fh} = $fh;
499 572
500 delete $self->{_skip_drain_rbuf}; 573 delete $self->{_skip_drain_rbuf};
501 $self->_start; 574 $self->_start;
508 }); 581 });
509 582
510 } else { 583 } else {
511 if ($self->{on_connect_error}) { 584 if ($self->{on_connect_error}) {
512 $self->{on_connect_error}($self, "$!"); 585 $self->{on_connect_error}($self, "$!");
513 $self->destroy; 586 $self->destroy if $self;
514 } else { 587 } else {
515 $self->_error ($!, 1); 588 $self->_error ($!, 1);
516 } 589 }
517 } 590 }
518 }, 591 },
519 sub { 592 sub {
520 local $self->{fh} = $_[0]; 593 local $self->{fh} = $_[0];
521 594
522 $self->{on_prepare} 595 $self->{on_prepare}
523 ? $self->{on_prepare}->($self) 596 ? $self->{on_prepare}->($self)
524 : () 597 : ()
525 } 598 }
526 ); 599 );
527 } 600 }
528 601
540 # with AnyEvent::Handle, do them a favour. 613 # with AnyEvent::Handle, do them a favour.
541 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE (); 614 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
542 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!" 615 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
543 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type; 616 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
544 617
545 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 618 AnyEvent::fh_unblock $self->{fh};
546 619
547 $self->{_activity} = 620 $self->{_activity} =
548 $self->{_ractivity} = 621 $self->{_ractivity} =
549 $self->{_wactivity} = AE::now; 622 $self->{_wactivity} = AE::now;
623
624 $self->{read_size} ||= 2048;
625 $self->{max_read_size} = $self->{read_size}
626 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
550 627
551 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 628 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
552 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 629 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
553 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 630 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
554 631
682 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1] 759 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
683 if $_[0]{fh}; 760 if $_[0]{fh};
684 }; 761 };
685} 762}
686 763
687=item $handle->keepalive ($boolean)
688
689Enables or disables the C<keepalive> setting (see constructor argument of
690the same name for details).
691
692=cut
693
694sub keepalive {
695 $_[0]{keepalive} = $_[1];
696
697 eval {
698 local $SIG{__DIE__};
699 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
700 if $_[0]{fh};
701 };
702}
703
704=item $handle->on_starttls ($cb) 764=item $handle->on_starttls ($cb)
705 765
706Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument). 766Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
707 767
708=cut 768=cut
723 783
724=item $handle->rbuf_max ($max_octets) 784=item $handle->rbuf_max ($max_octets)
725 785
726Configures the C<rbuf_max> setting (C<undef> disables it). 786Configures the C<rbuf_max> setting (C<undef> disables it).
727 787
788=item $handle->wbuf_max ($max_octets)
789
790Configures the C<wbuf_max> setting (C<undef> disables it).
791
728=cut 792=cut
729 793
730sub rbuf_max { 794sub rbuf_max {
731 $_[0]{rbuf_max} = $_[1]; 795 $_[0]{rbuf_max} = $_[1];
732} 796}
733 797
798sub wbuf_max {
799 $_[0]{wbuf_max} = $_[1];
800}
801
734############################################################################# 802#############################################################################
735 803
736=item $handle->timeout ($seconds) 804=item $handle->timeout ($seconds)
737 805
738=item $handle->rtimeout ($seconds) 806=item $handle->rtimeout ($seconds)
739 807
740=item $handle->wtimeout ($seconds) 808=item $handle->wtimeout ($seconds)
741 809
742Configures (or disables) the inactivity timeout. 810Configures (or disables) the inactivity timeout.
811
812The timeout will be checked instantly, so this method might destroy the
813handle before it returns.
743 814
744=item $handle->timeout_reset 815=item $handle->timeout_reset
745 816
746=item $handle->rtimeout_reset 817=item $handle->rtimeout_reset
747 818
831 902
832The write queue is very simple: you can add data to its end, and 903The write queue is very simple: you can add data to its end, and
833AnyEvent::Handle will automatically try to get rid of it for you. 904AnyEvent::Handle will automatically try to get rid of it for you.
834 905
835When data could be written and the write buffer is shorter then the low 906When data could be written and the write buffer is shorter then the low
836water mark, the C<on_drain> callback will be invoked. 907water mark, the C<on_drain> callback will be invoked once.
837 908
838=over 4 909=over 4
839 910
840=item $handle->on_drain ($cb) 911=item $handle->on_drain ($cb)
841 912
856 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 927 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
857} 928}
858 929
859=item $handle->push_write ($data) 930=item $handle->push_write ($data)
860 931
861Queues the given scalar to be written. You can push as much data as you 932Queues the given scalar to be written. You can push as much data as
862want (only limited by the available memory), as C<AnyEvent::Handle> 933you want (only limited by the available memory and C<wbuf_max>), as
863buffers it independently of the kernel. 934C<AnyEvent::Handle> buffers it independently of the kernel.
864 935
865This method may invoke callbacks (and therefore the handle might be 936This method may invoke callbacks (and therefore the handle might be
866destroyed after it returns). 937destroyed after it returns).
867 938
868=cut 939=cut
885 $self->{on_drain}($self) 956 $self->{on_drain}($self)
886 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) 957 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
887 && $self->{on_drain}; 958 && $self->{on_drain};
888 959
889 delete $self->{_ww} unless length $self->{wbuf}; 960 delete $self->{_ww} unless length $self->{wbuf};
890 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 961 } elsif ($! != EAGAIN && $! != EINTR && $! != EWOULDBLOCK && $! != WSAEWOULDBLOCK) {
891 $self->_error ($!, 1); 962 $self->_error ($!, 1);
892 } 963 }
893 }; 964 };
894 965
895 # try to write data immediately 966 # try to write data immediately
896 $cb->() unless $self->{autocork}; 967 $cb->() unless $self->{autocork};
897 968
898 # if still data left in wbuf, we need to poll 969 # if still data left in wbuf, we need to poll
899 $self->{_ww} = AE::io $self->{fh}, 1, $cb 970 $self->{_ww} = AE::io $self->{fh}, 1, $cb
900 if length $self->{wbuf}; 971 if length $self->{wbuf};
972
973 if (
974 defined $self->{wbuf_max}
975 && $self->{wbuf_max} < length $self->{wbuf}
976 ) {
977 $self->_error (Errno::ENOSPC, 1), return;
978 }
901 }; 979 };
902} 980}
903 981
904our %WH; 982our %WH;
905 983
976 1054
977Encodes the given hash or array reference into a JSON object. Unless you 1055Encodes the given hash or array reference into a JSON object. Unless you
978provide your own JSON object, this means it will be encoded to JSON text 1056provide your own JSON object, this means it will be encoded to JSON text
979in UTF-8. 1057in UTF-8.
980 1058
1059The default encoder might or might not handle every type of JSON value -
1060it might be limited to arrays and objects for security reasons. See the
1061C<json> constructor attribute for more details.
1062
981JSON objects (and arrays) are self-delimiting, so you can write JSON at 1063JSON objects (and arrays) are self-delimiting, so if you only use arrays
982one end of a handle and read them at the other end without using any 1064and hashes, you can write JSON at one end of a handle and read them at the
983additional framing. 1065other end without using any additional framing.
984 1066
985The generated JSON text is guaranteed not to contain any newlines: While 1067The JSON text generated by the default encoder is guaranteed not to
986this module doesn't need delimiters after or between JSON texts to be 1068contain any newlines: While this module doesn't need delimiters after or
987able to read them, many other languages depend on that. 1069between JSON texts to be able to read them, many other languages depend on
1070them.
988 1071
989A simple RPC protocol that interoperates easily with others is to send 1072A simple RPC protocol that interoperates easily with other languages is
990JSON arrays (or objects, although arrays are usually the better choice as 1073to send JSON arrays (or objects, although arrays are usually the better
991they mimic how function argument passing works) and a newline after each 1074choice as they mimic how function argument passing works) and a newline
992JSON text: 1075after each JSON text:
993 1076
994 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever 1077 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
995 $handle->push_write ("\012"); 1078 $handle->push_write ("\012");
996 1079
997An AnyEvent::Handle receiver would simply use the C<json> read type and 1080An AnyEvent::Handle receiver would simply use the C<json> read type and
1000 $handle->push_read (json => sub { my $array = $_[1]; ... }); 1083 $handle->push_read (json => sub { my $array = $_[1]; ... });
1001 1084
1002Other languages could read single lines terminated by a newline and pass 1085Other languages could read single lines terminated by a newline and pass
1003this line into their JSON decoder of choice. 1086this line into their JSON decoder of choice.
1004 1087
1088=item cbor => $perl_scalar
1089
1090Encodes the given scalar into a CBOR value. Unless you provide your own
1091L<CBOR::XS> object, this means it will be encoded to a CBOR string not
1092using any extensions, if possible.
1093
1094CBOR values are self-delimiting, so you can write CBOR at one end of
1095a handle and read them at the other end without using any additional
1096framing.
1097
1098A simple nd very very fast RPC protocol that interoperates with
1099other languages is to send CBOR and receive CBOR values (arrays are
1100recommended):
1101
1102 $handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
1103
1104An AnyEvent::Handle receiver would simply use the C<cbor> read type:
1105
1106 $handle->push_read (cbor => sub { my $array = $_[1]; ... });
1107
1005=cut 1108=cut
1006 1109
1007sub json_coder() { 1110sub json_coder() {
1008 eval { require JSON::XS; JSON::XS->new->utf8 } 1111 eval { require JSON::XS; JSON::XS->new->utf8 }
1009 || do { require JSON; JSON->new->utf8 } 1112 || do { require JSON::PP; JSON::PP->new->utf8 }
1010} 1113}
1011 1114
1012register_write_type json => sub { 1115register_write_type json => sub {
1013 my ($self, $ref) = @_; 1116 my ($self, $ref) = @_;
1014 1117
1015 my $json = $self->{json} ||= json_coder; 1118 ($self->{json} ||= json_coder)
1016
1017 $json->encode ($ref) 1119 ->encode ($ref)
1120};
1121
1122sub cbor_coder() {
1123 require CBOR::XS;
1124 CBOR::XS->new
1125}
1126
1127register_write_type cbor => sub {
1128 my ($self, $scalar) = @_;
1129
1130 ($self->{cbor} ||= cbor_coder)
1131 ->encode ($scalar)
1018}; 1132};
1019 1133
1020=item storable => $reference 1134=item storable => $reference
1021 1135
1022Freezes the given reference using L<Storable> and writes it to the 1136Freezes the given reference using L<Storable> and writes it to the
1025=cut 1139=cut
1026 1140
1027register_write_type storable => sub { 1141register_write_type storable => sub {
1028 my ($self, $ref) = @_; 1142 my ($self, $ref) = @_;
1029 1143
1030 require Storable; 1144 require Storable unless $Storable::VERSION;
1031 1145
1032 pack "w/a*", Storable::nfreeze ($ref) 1146 pack "w/a*", Storable::nfreeze ($ref)
1033}; 1147};
1034 1148
1035=back 1149=back
1040before it was actually written. One way to do that is to replace your 1154before it was actually written. One way to do that is to replace your
1041C<on_drain> handler by a callback that shuts down the socket (and set 1155C<on_drain> handler by a callback that shuts down the socket (and set
1042C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1156C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1043replaces the C<on_drain> callback with: 1157replaces the C<on_drain> callback with:
1044 1158
1045 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1159 sub { shutdown $_[0]{fh}, 1 }
1046 1160
1047This simply shuts down the write side and signals an EOF condition to the 1161This simply shuts down the write side and signals an EOF condition to the
1048the peer. 1162the peer.
1049 1163
1050You can rely on the normal read queue and C<on_eof> handling 1164You can rely on the normal read queue and C<on_eof> handling
1072 1186
1073Whenever the given C<type> is used, C<push_write> will the function with 1187Whenever the given C<type> is used, C<push_write> will the function with
1074the handle object and the remaining arguments. 1188the handle object and the remaining arguments.
1075 1189
1076The function is supposed to return a single octet string that will be 1190The function is supposed to return a single octet string that will be
1077appended to the write buffer, so you cna mentally treat this function as a 1191appended to the write buffer, so you can mentally treat this function as a
1078"arguments to on-the-wire-format" converter. 1192"arguments to on-the-wire-format" converter.
1079 1193
1080Example: implement a custom write type C<join> that joins the remaining 1194Example: implement a custom write type C<join> that joins the remaining
1081arguments using the first one. 1195arguments using the first one.
1082 1196
1376data. 1490data.
1377 1491
1378Example: read 2 bytes. 1492Example: read 2 bytes.
1379 1493
1380 $handle->push_read (chunk => 2, sub { 1494 $handle->push_read (chunk => 2, sub {
1381 warn "yay ", unpack "H*", $_[1]; 1495 say "yay " . unpack "H*", $_[1];
1382 }); 1496 });
1383 1497
1384=cut 1498=cut
1385 1499
1386register_read_type chunk => sub { 1500register_read_type chunk => sub {
1416 1530
1417register_read_type line => sub { 1531register_read_type line => sub {
1418 my ($self, $cb, $eol) = @_; 1532 my ($self, $cb, $eol) = @_;
1419 1533
1420 if (@_ < 3) { 1534 if (@_ < 3) {
1421 # this is more than twice as fast as the generic code below 1535 # this is faster then the generic code below
1422 sub { 1536 sub {
1423 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1537 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1538 or return;
1424 1539
1540 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1425 $cb->($_[0], $1, $2); 1541 $cb->($_[0], $str, "$1");
1426 1 1542 1
1427 } 1543 }
1428 } else { 1544 } else {
1429 $eol = quotemeta $eol unless ref $eol; 1545 $eol = quotemeta $eol unless ref $eol;
1430 $eol = qr|^(.*?)($eol)|s; 1546 $eol = qr|^(.*?)($eol)|s;
1431 1547
1432 sub { 1548 sub {
1433 $_[0]{rbuf} =~ s/$eol// or return; 1549 $_[0]{rbuf} =~ s/$eol// or return;
1434 1550
1435 $cb->($_[0], $1, $2); 1551 $cb->($_[0], "$1", "$2");
1436 1 1552 1
1437 } 1553 }
1438 } 1554 }
1439}; 1555};
1440 1556
1441=item regex => $accept[, $reject[, $skip], $cb->($handle, $data) 1557=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
1442 1558
1443Makes a regex match against the regex object C<$accept> and returns 1559Makes a regex match against the regex object C<$accept> and returns
1444everything up to and including the match. 1560everything up to and including the match. All the usual regex variables
1561($1, %+ etc.) from the regex match are available in the callback.
1445 1562
1446Example: read a single line terminated by '\n'. 1563Example: read a single line terminated by '\n'.
1447 1564
1448 $handle->push_read (regex => qr<\n>, sub { ... }); 1565 $handle->push_read (regex => qr<\n>, sub { ... });
1449 1566
1488 1605
1489 sub { 1606 sub {
1490 # accept 1607 # accept
1491 if ($$rbuf =~ $accept) { 1608 if ($$rbuf =~ $accept) {
1492 $data .= substr $$rbuf, 0, $+[0], ""; 1609 $data .= substr $$rbuf, 0, $+[0], "";
1493 $cb->($self, $data); 1610 $cb->($_[0], $data);
1494 return 1; 1611 return 1;
1495 } 1612 }
1496 1613
1497 # reject 1614 # reject
1498 if ($reject && $$rbuf =~ $reject) { 1615 if ($reject && $$rbuf =~ $reject) {
1499 $self->_error (Errno::EBADMSG); 1616 $_[0]->_error (Errno::EBADMSG);
1500 } 1617 }
1501 1618
1502 # skip 1619 # skip
1503 if ($skip && $$rbuf =~ $skip) { 1620 if ($skip && $$rbuf =~ $skip) {
1504 $data .= substr $$rbuf, 0, $+[0], ""; 1621 $data .= substr $$rbuf, 0, $+[0], "";
1520 my ($self, $cb) = @_; 1637 my ($self, $cb) = @_;
1521 1638
1522 sub { 1639 sub {
1523 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1640 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1524 if ($_[0]{rbuf} =~ /[^0-9]/) { 1641 if ($_[0]{rbuf} =~ /[^0-9]/) {
1525 $self->_error (Errno::EBADMSG); 1642 $_[0]->_error (Errno::EBADMSG);
1526 } 1643 }
1527 return; 1644 return;
1528 } 1645 }
1529 1646
1530 my $len = $1; 1647 my $len = $1;
1531 1648
1532 $self->unshift_read (chunk => $len, sub { 1649 $_[0]->unshift_read (chunk => $len, sub {
1533 my $string = $_[1]; 1650 my $string = $_[1];
1534 $_[0]->unshift_read (chunk => 1, sub { 1651 $_[0]->unshift_read (chunk => 1, sub {
1535 if ($_[1] eq ",") { 1652 if ($_[1] eq ",") {
1536 $cb->($_[0], $string); 1653 $cb->($_[0], $string);
1537 } else { 1654 } else {
1538 $self->_error (Errno::EBADMSG); 1655 $_[0]->_error (Errno::EBADMSG);
1539 } 1656 }
1540 }); 1657 });
1541 }); 1658 });
1542 1659
1543 1 1660 1
1593=item json => $cb->($handle, $hash_or_arrayref) 1710=item json => $cb->($handle, $hash_or_arrayref)
1594 1711
1595Reads a JSON object or array, decodes it and passes it to the 1712Reads a JSON object or array, decodes it and passes it to the
1596callback. When a parse error occurs, an C<EBADMSG> error will be raised. 1713callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1597 1714
1598If a C<json> object was passed to the constructor, then that will be used 1715If a C<json> object was passed to the constructor, then that will be
1599for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1716used for the final decode, otherwise it will create a L<JSON::XS> or
1717L<JSON::PP> coder object expecting UTF-8.
1600 1718
1601This read type uses the incremental parser available with JSON version 1719This read type uses the incremental parser available with JSON version
16022.09 (and JSON::XS version 2.2) and above. You have to provide a 17202.09 (and JSON::XS version 2.2) and above.
1603dependency on your own: this module will load the JSON module, but
1604AnyEvent does not depend on it itself.
1605 1721
1606Since JSON texts are fully self-delimiting, the C<json> read and write 1722Since JSON texts are fully self-delimiting, the C<json> read and write
1607types are an ideal simple RPC protocol: just exchange JSON datagrams. See 1723types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1608the C<json> write type description, above, for an actual example. 1724the C<json> write type description, above, for an actual example.
1609 1725
1613 my ($self, $cb) = @_; 1729 my ($self, $cb) = @_;
1614 1730
1615 my $json = $self->{json} ||= json_coder; 1731 my $json = $self->{json} ||= json_coder;
1616 1732
1617 my $data; 1733 my $data;
1618 my $rbuf = \$self->{rbuf};
1619 1734
1620 sub { 1735 sub {
1621 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1736 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1622 1737
1623 if ($ref) { 1738 if ($ref) {
1624 $self->{rbuf} = $json->incr_text; 1739 $_[0]{rbuf} = $json->incr_text;
1625 $json->incr_text = ""; 1740 $json->incr_text = "";
1626 $cb->($self, $ref); 1741 $cb->($_[0], $ref);
1627 1742
1628 1 1743 1
1629 } elsif ($@) { 1744 } elsif ($@) {
1630 # error case 1745 # error case
1631 $json->incr_skip; 1746 $json->incr_skip;
1632 1747
1633 $self->{rbuf} = $json->incr_text; 1748 $_[0]{rbuf} = $json->incr_text;
1634 $json->incr_text = ""; 1749 $json->incr_text = "";
1635 1750
1636 $self->_error (Errno::EBADMSG); 1751 $_[0]->_error (Errno::EBADMSG);
1637 1752
1638 () 1753 ()
1639 } else { 1754 } else {
1640 $self->{rbuf} = ""; 1755 $_[0]{rbuf} = "";
1641 1756
1757 ()
1758 }
1759 }
1760};
1761
1762=item cbor => $cb->($handle, $scalar)
1763
1764Reads a CBOR value, decodes it and passes it to the callback. When a parse
1765error occurs, an C<EBADMSG> error will be raised.
1766
1767If a L<CBOR::XS> object was passed to the constructor, then that will be
1768used for the final decode, otherwise it will create a CBOR coder without
1769enabling any options.
1770
1771You have to provide a dependency to L<CBOR::XS> on your own: this module
1772will load the L<CBOR::XS> module, but AnyEvent does not depend on it
1773itself.
1774
1775Since CBOR values are fully self-delimiting, the C<cbor> read and write
1776types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
1777the C<cbor> write type description, above, for an actual example.
1778
1779=cut
1780
1781register_read_type cbor => sub {
1782 my ($self, $cb) = @_;
1783
1784 my $cbor = $self->{cbor} ||= cbor_coder;
1785
1786 my $data;
1787
1788 sub {
1789 my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
1790
1791 if (@value) {
1792 $cb->($_[0], @value);
1793
1794 1
1795 } elsif ($@) {
1796 # error case
1797 $cbor->incr_reset;
1798
1799 $_[0]->_error (Errno::EBADMSG);
1800
1801 ()
1802 } else {
1642 () 1803 ()
1643 } 1804 }
1644 } 1805 }
1645}; 1806};
1646 1807
1655=cut 1816=cut
1656 1817
1657register_read_type storable => sub { 1818register_read_type storable => sub {
1658 my ($self, $cb) = @_; 1819 my ($self, $cb) = @_;
1659 1820
1660 require Storable; 1821 require Storable unless $Storable::VERSION;
1661 1822
1662 sub { 1823 sub {
1663 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1824 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1664 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1825 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1665 or return; 1826 or return;
1668 1829
1669 # bypass unshift if we already have the remaining chunk 1830 # bypass unshift if we already have the remaining chunk
1670 if ($format + $len <= length $_[0]{rbuf}) { 1831 if ($format + $len <= length $_[0]{rbuf}) {
1671 my $data = substr $_[0]{rbuf}, $format, $len; 1832 my $data = substr $_[0]{rbuf}, $format, $len;
1672 substr $_[0]{rbuf}, 0, $format + $len, ""; 1833 substr $_[0]{rbuf}, 0, $format + $len, "";
1834
1673 $cb->($_[0], Storable::thaw ($data)); 1835 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1836 or return $_[0]->_error (Errno::EBADMSG);
1674 } else { 1837 } else {
1675 # remove prefix 1838 # remove prefix
1676 substr $_[0]{rbuf}, 0, $format, ""; 1839 substr $_[0]{rbuf}, 0, $format, "";
1677 1840
1678 # read remaining chunk 1841 # read remaining chunk
1679 $_[0]->unshift_read (chunk => $len, sub { 1842 $_[0]->unshift_read (chunk => $len, sub {
1680 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1843 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1681 $cb->($_[0], $ref);
1682 } else {
1683 $self->_error (Errno::EBADMSG); 1844 or $_[0]->_error (Errno::EBADMSG);
1684 }
1685 }); 1845 });
1686 } 1846 }
1687 1847
1688 1 1848 1
1689 } 1849 }
1850};
1851
1852=item tls_detect => $cb->($handle, $detect, $major, $minor)
1853
1854Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1855record without consuming anything. Only SSL version 3 or higher
1856is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1857SSL2-compatible framing is supported).
1858
1859If it detects that the input data is likely TLS, it calls the callback
1860with a true value for C<$detect> and the (on-wire) TLS version as second
1861and third argument (C<$major> is C<3>, and C<$minor> is 0..4 for SSL
18623.0, TLS 1.0, 1.1, 1.2 and 1.3, respectively). If it detects the input
1863to be definitely not TLS, it calls the callback with a false value for
1864C<$detect>.
1865
1866The callback could use this information to decide whether or not to start
1867TLS negotiation.
1868
1869In all cases the data read so far is passed to the following read
1870handlers.
1871
1872Usually you want to use the C<tls_autostart> read type instead.
1873
1874If you want to design a protocol that works in the presence of TLS
1875dtection, make sure that any non-TLS data doesn't start with the octet 22
1876(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1877read type does are a bit more strict, but might losen in the future to
1878accomodate protocol changes.
1879
1880This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1881L<Net::SSLeay>).
1882
1883=item tls_autostart => [$tls_ctx, ]$tls
1884
1885Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1886to start tls by calling C<starttls> with the given arguments.
1887
1888In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1889been configured to accept, as servers do not normally send a handshake on
1890their own and ths cannot be detected in this way.
1891
1892See C<tls_detect> above for more details.
1893
1894Example: give the client a chance to start TLS before accepting a text
1895line.
1896
1897 $hdl->push_read (tls_autostart => "accept");
1898 $hdl->push_read (line => sub {
1899 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1900 });
1901
1902=cut
1903
1904register_read_type tls_detect => sub {
1905 my ($self, $cb) = @_;
1906
1907 sub {
1908 # this regex matches a full or partial tls record
1909 if (
1910 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1911 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1912 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1913 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1914 ) {
1915 return if 3 != length $1; # partial match, can't decide yet
1916
1917 # full match, valid TLS record
1918 my ($major, $minor) = unpack "CC", $1;
1919 $cb->($self, "accept", $major, $minor);
1920 } else {
1921 # mismatch == guaranteed not TLS
1922 $cb->($self, undef);
1923 }
1924
1925 1
1926 }
1927};
1928
1929register_read_type tls_autostart => sub {
1930 my ($self, @tls) = @_;
1931
1932 $RH{tls_detect}($self, sub {
1933 return unless $_[1];
1934 $_[0]->starttls (@tls);
1935 })
1690}; 1936};
1691 1937
1692=back 1938=back
1693 1939
1694=item custom read types - Package::anyevent_read_type $handle, $cb, @args 1940=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1726Note that AnyEvent::Handle will automatically C<start_read> for you when 1972Note that AnyEvent::Handle will automatically C<start_read> for you when
1727you change the C<on_read> callback or push/unshift a read callback, and it 1973you change the C<on_read> callback or push/unshift a read callback, and it
1728will automatically C<stop_read> for you when neither C<on_read> is set nor 1974will automatically C<stop_read> for you when neither C<on_read> is set nor
1729there are any read requests in the queue. 1975there are any read requests in the queue.
1730 1976
1731These methods will have no effect when in TLS mode (as TLS doesn't support 1977In older versions of this module (<= 5.3), these methods had no effect,
1732half-duplex connections). 1978as TLS does not support half-duplex connections. In current versions they
1979work as expected, as this behaviour is required to avoid certain resource
1980attacks, where the program would be forced to read (and buffer) arbitrary
1981amounts of data before being able to send some data. The drawback is that
1982some readings of the the SSL/TLS specifications basically require this
1983attack to be working, as SSL/TLS implementations might stall sending data
1984during a rehandshake.
1985
1986As a guideline, during the initial handshake, you should not stop reading,
1987and as a client, it might cause problems, depending on your application.
1733 1988
1734=cut 1989=cut
1735 1990
1736sub stop_read { 1991sub stop_read {
1737 my ($self) = @_; 1992 my ($self) = @_;
1738 1993
1739 delete $self->{_rw} unless $self->{tls}; 1994 delete $self->{_rw};
1740} 1995}
1741 1996
1742sub start_read { 1997sub start_read {
1743 my ($self) = @_; 1998 my ($self) = @_;
1744 1999
1745 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) { 2000 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1746 Scalar::Util::weaken $self; 2001 Scalar::Util::weaken $self;
1747 2002
1748 $self->{_rw} = AE::io $self->{fh}, 0, sub { 2003 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1749 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 2004 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1750 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 2005 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1751 2006
1752 if ($len > 0) { 2007 if ($len > 0) {
1753 $self->{_activity} = $self->{_ractivity} = AE::now; 2008 $self->{_activity} = $self->{_ractivity} = AE::now;
1754 2009
1755 if ($self->{tls}) { 2010 if ($self->{tls}) {
1758 &_dotls ($self); 2013 &_dotls ($self);
1759 } else { 2014 } else {
1760 $self->_drain_rbuf; 2015 $self->_drain_rbuf;
1761 } 2016 }
1762 2017
2018 if ($len == $self->{read_size}) {
2019 $self->{read_size} *= 2;
2020 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
2021 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
2022 }
2023
1763 } elsif (defined $len) { 2024 } elsif (defined $len) {
1764 delete $self->{_rw}; 2025 delete $self->{_rw};
1765 $self->{_eof} = 1; 2026 $self->{_eof} = 1;
1766 $self->_drain_rbuf; 2027 $self->_drain_rbuf;
1767 2028
1768 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 2029 } elsif ($! != EAGAIN && $! != EINTR && $! != EWOULDBLOCK && $! != WSAEWOULDBLOCK) {
1769 return $self->_error ($!, 1); 2030 return $self->_error ($!, 1);
1770 } 2031 }
1771 }; 2032 };
1772 } 2033 }
1773} 2034}
1779 my ($self, $err) = @_; 2040 my ($self, $err) = @_;
1780 2041
1781 return $self->_error ($!, 1) 2042 return $self->_error ($!, 1)
1782 if $err == Net::SSLeay::ERROR_SYSCALL (); 2043 if $err == Net::SSLeay::ERROR_SYSCALL ();
1783 2044
1784 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 2045 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1785 2046
1786 # reduce error string to look less scary 2047 # reduce error string to look less scary
1787 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 2048 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1788 2049
1789 if ($self->{_on_starttls}) { 2050 if ($self->{_on_starttls}) {
1795 } 2056 }
1796} 2057}
1797 2058
1798# poll the write BIO and send the data if applicable 2059# poll the write BIO and send the data if applicable
1799# also decode read data if possible 2060# also decode read data if possible
1800# this is basiclaly our TLS state machine 2061# this is basically our TLS state machine
1801# more efficient implementations are possible with openssl, 2062# more efficient implementations are possible with openssl,
1802# but not with the buggy and incomplete Net::SSLeay. 2063# but not with the buggy and incomplete Net::SSLeay.
1803sub _dotls { 2064sub _dotls {
1804 my ($self) = @_; 2065 my ($self) = @_;
1805 2066
1806 my $tmp; 2067 my $tmp;
1807 2068
1808 if (length $self->{_tls_wbuf}) { 2069 while (length $self->{_tls_wbuf}) {
1809 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 2070 if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
1810 substr $self->{_tls_wbuf}, 0, $tmp, ""; 2071 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
2072
2073 return $self->_tls_error ($tmp)
2074 if $tmp != $ERROR_WANT_READ
2075 && ($tmp != $ERROR_SYSCALL || $!);
2076
2077 last;
1811 } 2078 }
1812 2079
1813 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp); 2080 substr $self->{_tls_wbuf}, 0, $tmp, "";
1814 return $self->_tls_error ($tmp)
1815 if $tmp != $ERROR_WANT_READ
1816 && ($tmp != $ERROR_SYSCALL || $!);
1817 } 2081 }
1818 2082
1819 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 2083 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1820 unless (length $tmp) { 2084 unless (length $tmp) {
1821 $self->{_on_starttls} 2085 $self->{_on_starttls}
1835 $self->{_tls_rbuf} .= $tmp; 2099 $self->{_tls_rbuf} .= $tmp;
1836 $self->_drain_rbuf; 2100 $self->_drain_rbuf;
1837 $self->{tls} or return; # tls session might have gone away in callback 2101 $self->{tls} or return; # tls session might have gone away in callback
1838 } 2102 }
1839 2103
1840 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 2104 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
1841 return $self->_tls_error ($tmp) 2105 return $self->_tls_error ($tmp)
1842 if $tmp != $ERROR_WANT_READ 2106 if $tmp != $ERROR_WANT_READ
1843 && ($tmp != $ERROR_SYSCALL || $!); 2107 && ($tmp != $ERROR_SYSCALL || $!);
1844 2108
1845 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2109 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1855 2119
1856=item $handle->starttls ($tls[, $tls_ctx]) 2120=item $handle->starttls ($tls[, $tls_ctx])
1857 2121
1858Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2122Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1859object is created, you can also do that at a later time by calling 2123object is created, you can also do that at a later time by calling
1860C<starttls>. 2124C<starttls>. See the C<tls> constructor argument for general info.
1861 2125
1862Starting TLS is currently an asynchronous operation - when you push some 2126Starting TLS is currently an asynchronous operation - when you push some
1863write data and then call C<< ->starttls >> then TLS negotiation will start 2127write data and then call C<< ->starttls >> then TLS negotiation will start
1864immediately, after which the queued write data is then sent. 2128immediately, after which the queued write data is then sent. This might
2129change in future versions, so best make sure you have no outstanding write
2130data when calling this method.
1865 2131
1866The first argument is the same as the C<tls> constructor argument (either 2132The first argument is the same as the C<tls> constructor argument (either
1867C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2133C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1868 2134
1869The second argument is the optional C<AnyEvent::TLS> object that is used 2135The second argument is the optional C<AnyEvent::TLS> object that is used
1891 my ($self, $tls, $ctx) = @_; 2157 my ($self, $tls, $ctx) = @_;
1892 2158
1893 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 2159 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1894 if $self->{tls}; 2160 if $self->{tls};
1895 2161
2162 unless (defined $AnyEvent::TLS::VERSION) {
2163 eval {
2164 require Net::SSLeay;
2165 require AnyEvent::TLS;
2166 1
2167 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2168 }
2169
1896 $self->{tls} = $tls; 2170 $self->{tls} = $tls;
1897 $self->{tls_ctx} = $ctx if @_ > 2; 2171 $self->{tls_ctx} = $ctx if @_ > 2;
1898 2172
1899 return unless $self->{fh}; 2173 return unless $self->{fh};
1900 2174
1901 require Net::SSLeay;
1902
1903 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2175 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1904 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2176 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1905 2177
1906 $tls = delete $self->{tls}; 2178 $tls = delete $self->{tls};
1907 $ctx = $self->{tls_ctx}; 2179 $ctx = $self->{tls_ctx};
1908 2180
1909 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2181 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1910 2182
1911 if ("HASH" eq ref $ctx) { 2183 if ("HASH" eq ref $ctx) {
1912 require AnyEvent::TLS;
1913
1914 if ($ctx->{cache}) { 2184 if ($ctx->{cache}) {
1915 my $key = $ctx+0; 2185 my $key = $ctx+0;
1916 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2186 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1917 } else { 2187 } else {
1918 $ctx = new AnyEvent::TLS %$ctx; 2188 $ctx = new AnyEvent::TLS %$ctx;
1923 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername}); 2193 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1924 2194
1925 # basically, this is deep magic (because SSL_read should have the same issues) 2195 # basically, this is deep magic (because SSL_read should have the same issues)
1926 # but the openssl maintainers basically said: "trust us, it just works". 2196 # but the openssl maintainers basically said: "trust us, it just works".
1927 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2197 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1928 # and mismaintained ssleay-module doesn't even offer them). 2198 # and mismaintained ssleay-module didn't offer them for a decade or so).
1929 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 2199 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1930 # 2200 #
1931 # in short: this is a mess. 2201 # in short: this is a mess.
1932 # 2202 #
1933 # note that we do not try to keep the length constant between writes as we are required to do. 2203 # note that we do not try to keep the length constant between writes as we are required to do.
1934 # we assume that most (but not all) of this insanity only applies to non-blocking cases, 2204 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1935 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to 2205 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1936 # have identity issues in that area. 2206 # have identity issues in that area.
1937# Net::SSLeay::CTX_set_mode ($ssl, 2207# Net::SSLeay::set_mode ($ssl,
1938# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2208# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1939# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2209# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1940 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2210 Net::SSLeay::set_mode ($tls, 1|2);
1941 2211
1942 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2212 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1943 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2213 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1944 2214
1945 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2215 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2216 $self->{rbuf} = "";
1946 2217
1947 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2218 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1948 2219
1949 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2220 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1950 if $self->{on_starttls}; 2221 if $self->{on_starttls};
1984 2255
1985 return unless $self->{tls}; 2256 return unless $self->{tls};
1986 2257
1987 $self->{tls_ctx}->_put_session (delete $self->{tls}) 2258 $self->{tls_ctx}->_put_session (delete $self->{tls})
1988 if $self->{tls} > 0; 2259 if $self->{tls} > 0;
1989 2260
1990 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2261 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1991} 2262}
2263
2264=item $handle->resettls
2265
2266This rarely-used method simply resets and TLS state on the handle, usually
2267causing data loss.
2268
2269One case where it may be useful is when you want to skip over the data in
2270the stream but you are not interested in interpreting it, so data loss is
2271no concern.
2272
2273=cut
2274
2275*resettls = \&_freetls;
1992 2276
1993sub DESTROY { 2277sub DESTROY {
1994 my ($self) = @_; 2278 my ($self) = @_;
1995 2279
1996 &_freetls; 2280 &_freetls;
2006 push @linger, AE::io $fh, 1, sub { 2290 push @linger, AE::io $fh, 1, sub {
2007 my $len = syswrite $fh, $wbuf, length $wbuf; 2291 my $len = syswrite $fh, $wbuf, length $wbuf;
2008 2292
2009 if ($len > 0) { 2293 if ($len > 0) {
2010 substr $wbuf, 0, $len, ""; 2294 substr $wbuf, 0, $len, "";
2011 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) { 2295 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != EWOULDBLOCK && $! != WSAEWOULDBLOCK)) {
2012 @linger = (); # end 2296 @linger = (); # end
2013 } 2297 }
2014 }; 2298 };
2015 push @linger, AE::timer $linger, 0, sub { 2299 push @linger, AE::timer $linger, 0, sub {
2016 @linger = (); 2300 @linger = ();
2112 2396
2113It is only safe to "forget" the reference inside EOF or error callbacks, 2397It is only safe to "forget" the reference inside EOF or error callbacks,
2114from within all other callbacks, you need to explicitly call the C<< 2398from within all other callbacks, you need to explicitly call the C<<
2115->destroy >> method. 2399->destroy >> method.
2116 2400
2401=item Why is my C<on_eof> callback never called?
2402
2403Probably because your C<on_error> callback is being called instead: When
2404you have outstanding requests in your read queue, then an EOF is
2405considered an error as you clearly expected some data.
2406
2407To avoid this, make sure you have an empty read queue whenever your handle
2408is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2409an C<on_read> handler that simply pushes the first read requests in the
2410queue.
2411
2412See also the next question, which explains this in a bit more detail.
2413
2414=item How can I serve requests in a loop?
2415
2416Most protocols consist of some setup phase (authentication for example)
2417followed by a request handling phase, where the server waits for requests
2418and handles them, in a loop.
2419
2420There are two important variants: The first (traditional, better) variant
2421handles requests until the server gets some QUIT command, causing it to
2422close the connection first (highly desirable for a busy TCP server). A
2423client dropping the connection is an error, which means this variant can
2424detect an unexpected detection close.
2425
2426To handle this case, always make sure you have a non-empty read queue, by
2427pushing the "read request start" handler on it:
2428
2429 # we assume a request starts with a single line
2430 my @start_request; @start_request = (line => sub {
2431 my ($hdl, $line) = @_;
2432
2433 ... handle request
2434
2435 # push next request read, possibly from a nested callback
2436 $hdl->push_read (@start_request);
2437 });
2438
2439 # auth done, now go into request handling loop
2440 # now push the first @start_request
2441 $hdl->push_read (@start_request);
2442
2443By always having an outstanding C<push_read>, the handle always expects
2444some data and raises the C<EPIPE> error when the connction is dropped
2445unexpectedly.
2446
2447The second variant is a protocol where the client can drop the connection
2448at any time. For TCP, this means that the server machine may run out of
2449sockets easier, and in general, it means you cannot distinguish a protocl
2450failure/client crash from a normal connection close. Nevertheless, these
2451kinds of protocols are common (and sometimes even the best solution to the
2452problem).
2453
2454Having an outstanding read request at all times is possible if you ignore
2455C<EPIPE> errors, but this doesn't help with when the client drops the
2456connection during a request, which would still be an error.
2457
2458A better solution is to push the initial request read in an C<on_read>
2459callback. This avoids an error, as when the server doesn't expect data
2460(i.e. is idly waiting for the next request, an EOF will not raise an
2461error, but simply result in an C<on_eof> callback. It is also a bit slower
2462and simpler:
2463
2464 # auth done, now go into request handling loop
2465 $hdl->on_read (sub {
2466 my ($hdl) = @_;
2467
2468 # called each time we receive data but the read queue is empty
2469 # simply start read the request
2470
2471 $hdl->push_read (line => sub {
2472 my ($hdl, $line) = @_;
2473
2474 ... handle request
2475
2476 # do nothing special when the request has been handled, just
2477 # let the request queue go empty.
2478 });
2479 });
2480
2117=item I get different callback invocations in TLS mode/Why can't I pause 2481=item I get different callback invocations in TLS mode/Why can't I pause
2118reading? 2482reading?
2119 2483
2120Unlike, say, TCP, TLS connections do not consist of two independent 2484Unlike, say, TCP, TLS connections do not consist of two independent
2121communication channels, one for each direction. Or put differently, the 2485communication channels, one for each direction. Or put differently, the
2142 $handle->on_eof (undef); 2506 $handle->on_eof (undef);
2143 $handle->on_error (sub { 2507 $handle->on_error (sub {
2144 my $data = delete $_[0]{rbuf}; 2508 my $data = delete $_[0]{rbuf};
2145 }); 2509 });
2146 2510
2511Note that this example removes the C<rbuf> member from the handle object,
2512which is not normally allowed by the API. It is expressly permitted in
2513this case only, as the handle object needs to be destroyed afterwards.
2514
2147The reason to use C<on_error> is that TCP connections, due to latencies 2515The reason to use C<on_error> is that TCP connections, due to latencies
2148and packets loss, might get closed quite violently with an error, when in 2516and packets loss, might get closed quite violently with an error, when in
2149fact all data has been received. 2517fact all data has been received.
2150 2518
2151It is usually better to use acknowledgements when transferring data, 2519It is usually better to use acknowledgements when transferring data,
2161C<low_water_mark> this will be called precisely when all data has been 2529C<low_water_mark> this will be called precisely when all data has been
2162written to the socket: 2530written to the socket:
2163 2531
2164 $handle->push_write (...); 2532 $handle->push_write (...);
2165 $handle->on_drain (sub { 2533 $handle->on_drain (sub {
2166 warn "all data submitted to the kernel\n"; 2534 AE::log debug => "All data submitted to the kernel.";
2167 undef $handle; 2535 undef $handle;
2168 }); 2536 });
2169 2537
2170If you just want to queue some data and then signal EOF to the other side, 2538If you just want to queue some data and then signal EOF to the other side,
2171consider using C<< ->push_shutdown >> instead. 2539consider using C<< ->push_shutdown >> instead.
2255When you have intermediate CA certificates that your clients might not 2623When you have intermediate CA certificates that your clients might not
2256know about, just append them to the C<cert_file>. 2624know about, just append them to the C<cert_file>.
2257 2625
2258=back 2626=back
2259 2627
2260
2261=head1 SUBCLASSING AnyEvent::Handle 2628=head1 SUBCLASSING AnyEvent::Handle
2262 2629
2263In many cases, you might want to subclass AnyEvent::Handle. 2630In many cases, you might want to subclass AnyEvent::Handle.
2264 2631
2265To make this easier, a given version of AnyEvent::Handle uses these 2632To make this easier, a given version of AnyEvent::Handle uses these
2291 2658
2292Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2659Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2293 2660
2294=cut 2661=cut
2295 2662
22961; # End of AnyEvent::Handle 26631
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