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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.205 by root, Mon Nov 15 17:11:00 2010 UTC vs.
Revision 1.241 by root, Fri Sep 5 22:17:26 2014 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
114=over 4 114=over 4
115 115
116=item on_prepare => $cb->($handle) 116=item on_prepare => $cb->($handle)
117 117
118This (rarely used) callback is called before a new connection is 118This (rarely used) callback is called before a new connection is
119attempted, but after the file handle has been created. It could be used to 119attempted, but after the file handle has been created (you can access that
120file handle via C<< $handle->{fh} >>). It could be used to prepare the
120prepare the file handle with parameters required for the actual connect 121file handle with parameters required for the actual connect (as opposed to
121(as opposed to settings that can be changed when the connection is already 122settings that can be changed when the connection is already established).
122established).
123 123
124The return value of this callback should be the connect timeout value in 124The return value of this callback should be the connect timeout value in
125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126default timeout is to be used). 126default timeout is to be used).
127 127
128=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
129 129
130This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
131 131
132The peer's numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback. 133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
134 136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
135If, for some reason, the handle is not acceptable, calling C<$retry> 140If, for some reason, the handle is not acceptable, calling C<$retry> will
136will continue with the next connection target (in case of multi-homed 141continue with the next connection target (in case of multi-homed hosts or
137hosts or SRV records there can be multiple connection endpoints). At the 142SRV records there can be multiple connection endpoints). The C<$retry>
138time it is called the read and write queues, eof status, tls status and 143callback can be invoked after the connect callback returns, i.e. one can
139similar properties of the handle will have been reset. 144start a handshake and then decide to retry with the next host if the
145handshake fails.
140 146
141In most cases, you should ignore the C<$retry> parameter. 147In most cases, you should ignore the C<$retry> parameter.
142 148
143=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
144 150
164with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
165cases where the other side can close the connection at will, it is 171cases where the other side can close the connection at will, it is
166often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
167 173
168AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
169against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well.
170recommended to always output the C<$message> argument in human-readable 176
171error messages (it's usually the same as C<"$!">). 177If you report the error to the user, it is recommended to always output
178the C<$message> argument in human-readable error messages (you don't need
179to report C<"$!"> if you report C<$message>).
180
181If you want to react programmatically to the error, then looking at C<$!>
182and comparing it against some of the documented C<Errno> values is usually
183better than looking at the C<$message>.
172 184
173Non-fatal errors can be retried by returning, but it is recommended 185Non-fatal errors can be retried by returning, but it is recommended
174to simply ignore this parameter and instead abondon the handle object 186to simply ignore this parameter and instead abondon the handle object
175when this callback is invoked. Examples of non-fatal errors are timeouts 187when this callback is invoked. Examples of non-fatal errors are timeouts
176C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
224If an EOF condition has been detected but no C<on_eof> callback has been 236If an EOF condition has been detected but no C<on_eof> callback has been
225set, then a fatal error will be raised with C<$!> set to <0>. 237set, then a fatal error will be raised with C<$!> set to <0>.
226 238
227=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
228 240
229This sets the callback that is called when the write buffer becomes empty 241This sets the callback that is called once when the write buffer becomes
230(or immediately if the buffer is empty already). 242empty (and immediately when the handle object is created).
231 243
232To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
233 245
234This callback is useful when you don't want to put all of your write data 246This callback is useful when you don't want to put all of your write data
235into the queue at once, for example, when you want to write the contents 247into the queue at once, for example, when you want to write the contents
247many seconds pass without a successful read or write on the underlying 259many seconds pass without a successful read or write on the underlying
248file handle (or a call to C<timeout_reset>), the C<on_timeout> callback 260file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
249will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> 261will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
250error will be raised). 262error will be raised).
251 263
252There are three variants of the timeouts that work independently 264There are three variants of the timeouts that work independently of each
253of each other, for both read and write, just read, and just write: 265other, for both read and write (triggered when nothing was read I<OR>
266written), just read (triggered when nothing was read), and just write:
254C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 267C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
255C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 268C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
256C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 269C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
257 270
258Note that timeout processing is active even when you do not have 271Note that timeout processing is active even when you do not have any
259any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
260idle then you should disable the timeout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
261in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 274timeout in the corresponding C<on_timeout> callback, in which case
262restart the timeout. 275AnyEvent::Handle will simply restart the timeout.
263 276
264Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
265 278
266=item on_timeout => $cb->($handle) 279=item on_timeout => $cb->($handle)
280
281=item on_rtimeout => $cb->($handle)
282
283=item on_wtimeout => $cb->($handle)
267 284
268Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
269callback, then the timeout will be reset as if some activity had happened, 286callback, then the timeout will be reset as if some activity had happened,
270so this condition is not fatal in any way. 287so this condition is not fatal in any way.
271 288
278For example, a server accepting connections from untrusted sources should 295For example, a server accepting connections from untrusted sources should
279be configured to accept only so-and-so much data that it cannot act on 296be configured to accept only so-and-so much data that it cannot act on
280(for example, when expecting a line, an attacker could send an unlimited 297(for example, when expecting a line, an attacker could send an unlimited
281amount of data without a callback ever being called as long as the line 298amount of data without a callback ever being called as long as the line
282isn't finished). 299isn't finished).
300
301=item wbuf_max => <bytes>
302
303If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
304when the write buffer ever (strictly) exceeds this size. This is useful to
305avoid some forms of denial-of-service attacks.
306
307Although the units of this parameter is bytes, this is the I<raw> number
308of bytes not yet accepted by the kernel. This can make a difference when
309you e.g. use TLS, as TLS typically makes your write data larger (but it
310can also make it smaller due to compression).
311
312As an example of when this limit is useful, take a chat server that sends
313chat messages to a client. If the client does not read those in a timely
314manner then the send buffer in the server would grow unbounded.
283 315
284=item autocork => <boolean> 316=item autocork => <boolean>
285 317
286When disabled (the default), C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
287write the data to the handle if possible. This avoids having to register 319write the data to the handle if possible. This avoids having to register
339already have occured on BSD systems), but at least it will protect you 371already have occured on BSD systems), but at least it will protect you
340from most attacks. 372from most attacks.
341 373
342=item read_size => <bytes> 374=item read_size => <bytes>
343 375
344The initial read block size, the number of bytes this module will try to 376The initial read block size, the number of bytes this module will try
345read during each loop iteration. Each handle object will consume at least 377to read during each loop iteration. Each handle object will consume
346this amount of memory for the read buffer as well, so when handling many 378at least this amount of memory for the read buffer as well, so when
347connections requirements). See also C<max_read_size>. Default: C<2048>. 379handling many connections watch out for memory requirements). See also
380C<max_read_size>. Default: C<2048>.
348 381
349=item max_read_size => <bytes> 382=item max_read_size => <bytes>
350 383
351The maximum read buffer size used by the dynamic adjustment 384The maximum read buffer size used by the dynamic adjustment
352algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in 385algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
396appropriate error message. 429appropriate error message.
397 430
398TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
399automatically when you try to create a TLS handle): this module doesn't 432automatically when you try to create a TLS handle): this module doesn't
400have a dependency on that module, so if your module requires it, you have 433have a dependency on that module, so if your module requires it, you have
401to add the dependency yourself. 434to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
435old, you get an C<EPROTO> error.
402 436
403Unlike TCP, TLS has a server and client side: for the TLS server side, use 437Unlike TCP, TLS has a server and client side: for the TLS server side, use
404C<accept>, and for the TLS client side of a connection, use C<connect> 438C<accept>, and for the TLS client side of a connection, use C<connect>
405mode. 439mode.
406 440
422Use the C<< ->starttls >> method if you need to start TLS negotiation later. 456Use the C<< ->starttls >> method if you need to start TLS negotiation later.
423 457
424=item tls_ctx => $anyevent_tls 458=item tls_ctx => $anyevent_tls
425 459
426Use the given C<AnyEvent::TLS> object to create the new TLS connection 460Use the given C<AnyEvent::TLS> object to create the new TLS connection
427(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
428missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 462parameter is missing (or C<undef>), then AnyEvent::Handle will use
463C<AnyEvent::Handle::TLS_CTX>.
429 464
430Instead of an object, you can also specify a hash reference with C<< key 465Instead of an object, you can also specify a hash reference with C<< key
431=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 466=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
432new TLS context object. 467new TLS context object.
433 468
461callback. 496callback.
462 497
463This callback will only be called on TLS shutdowns, not when the 498This callback will only be called on TLS shutdowns, not when the
464underlying handle signals EOF. 499underlying handle signals EOF.
465 500
466=item json => JSON or JSON::XS object 501=item json => L<JSON>, L<JSON::PP> or L<JSON::XS> object
467 502
468This is the json coder object used by the C<json> read and write types. 503This is the json coder object used by the C<json> read and write types.
469 504
470If you don't supply it, then AnyEvent::Handle will create and use a 505If you don't supply it, then AnyEvent::Handle will create and use a
471suitable one (on demand), which will write and expect UTF-8 encoded JSON 506suitable one (on demand), which will write and expect UTF-8 encoded
507JSON texts (either using L<JSON::XS> or L<JSON>). The written texts are
508guaranteed not to contain any newline character.
509
510For security reasons, this encoder will likely I<not> handle numbers and
511strings, only arrays and objects/hashes. The reason is that originally
512JSON was self-delimited, but Dougles Crockford thought it was a splendid
513idea to redefine JSON incompatibly, so this is no longer true.
514
515For protocols that used back-to-back JSON texts, this might lead to
516run-ins, where two or more JSON texts will be interpreted as one JSON
472texts. 517text.
473 518
519For this reason, if the default encoder uses L<JSON::XS>, it will default
520to not allowing anything but arrays and objects/hashes, at least for the
521forseeable future (it will change at some point). This might or might not
522be true for the L<JSON> module, so this might cause a security issue.
523
524If you depend on either behaviour, you should create your own json object
525and pass it in explicitly.
526
527=item cbor => L<CBOR::XS> object
528
529This is the cbor coder object used by the C<cbor> read and write types.
530
531If you don't supply it, then AnyEvent::Handle will create and use a
532suitable one (on demand), which will write CBOR without using extensions,
533if possible.
534
474Note that you are responsible to depend on the JSON module if you want to 535Note that you are responsible to depend on the L<CBOR::XS> module if you
475use this functionality, as AnyEvent does not have a dependency itself. 536want to use this functionality, as AnyEvent does not have a dependency on
537it itself.
476 538
477=back 539=back
478 540
479=cut 541=cut
480 542
502 $self->{connect}[0], 564 $self->{connect}[0],
503 $self->{connect}[1], 565 $self->{connect}[1],
504 sub { 566 sub {
505 my ($fh, $host, $port, $retry) = @_; 567 my ($fh, $host, $port, $retry) = @_;
506 568
507 delete $self->{_connect}; 569 delete $self->{_connect}; # no longer needed
508 570
509 if ($fh) { 571 if ($fh) {
510 $self->{fh} = $fh; 572 $self->{fh} = $fh;
511 573
512 delete $self->{_skip_drain_rbuf}; 574 delete $self->{_skip_drain_rbuf};
520 }); 582 });
521 583
522 } else { 584 } else {
523 if ($self->{on_connect_error}) { 585 if ($self->{on_connect_error}) {
524 $self->{on_connect_error}($self, "$!"); 586 $self->{on_connect_error}($self, "$!");
525 $self->destroy; 587 $self->destroy if $self;
526 } else { 588 } else {
527 $self->_error ($!, 1); 589 $self->_error ($!, 1);
528 } 590 }
529 } 591 }
530 }, 592 },
531 sub { 593 sub {
532 local $self->{fh} = $_[0]; 594 local $self->{fh} = $_[0];
533 595
534 $self->{on_prepare} 596 $self->{on_prepare}
535 ? $self->{on_prepare}->($self) 597 ? $self->{on_prepare}->($self)
536 : () 598 : ()
537 } 599 }
538 ); 600 );
539 } 601 }
540 602
739 801
740=item $handle->rbuf_max ($max_octets) 802=item $handle->rbuf_max ($max_octets)
741 803
742Configures the C<rbuf_max> setting (C<undef> disables it). 804Configures the C<rbuf_max> setting (C<undef> disables it).
743 805
806=item $handle->wbuf_max ($max_octets)
807
808Configures the C<wbuf_max> setting (C<undef> disables it).
809
744=cut 810=cut
745 811
746sub rbuf_max { 812sub rbuf_max {
747 $_[0]{rbuf_max} = $_[1]; 813 $_[0]{rbuf_max} = $_[1];
748} 814}
749 815
816sub wbuf_max {
817 $_[0]{wbuf_max} = $_[1];
818}
819
750############################################################################# 820#############################################################################
751 821
752=item $handle->timeout ($seconds) 822=item $handle->timeout ($seconds)
753 823
754=item $handle->rtimeout ($seconds) 824=item $handle->rtimeout ($seconds)
755 825
756=item $handle->wtimeout ($seconds) 826=item $handle->wtimeout ($seconds)
757 827
758Configures (or disables) the inactivity timeout. 828Configures (or disables) the inactivity timeout.
829
830The timeout will be checked instantly, so this method might destroy the
831handle before it returns.
759 832
760=item $handle->timeout_reset 833=item $handle->timeout_reset
761 834
762=item $handle->rtimeout_reset 835=item $handle->rtimeout_reset
763 836
847 920
848The write queue is very simple: you can add data to its end, and 921The write queue is very simple: you can add data to its end, and
849AnyEvent::Handle will automatically try to get rid of it for you. 922AnyEvent::Handle will automatically try to get rid of it for you.
850 923
851When data could be written and the write buffer is shorter then the low 924When data could be written and the write buffer is shorter then the low
852water mark, the C<on_drain> callback will be invoked. 925water mark, the C<on_drain> callback will be invoked once.
853 926
854=over 4 927=over 4
855 928
856=item $handle->on_drain ($cb) 929=item $handle->on_drain ($cb)
857 930
872 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 945 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
873} 946}
874 947
875=item $handle->push_write ($data) 948=item $handle->push_write ($data)
876 949
877Queues the given scalar to be written. You can push as much data as you 950Queues the given scalar to be written. You can push as much data as
878want (only limited by the available memory), as C<AnyEvent::Handle> 951you want (only limited by the available memory and C<wbuf_max>), as
879buffers it independently of the kernel. 952C<AnyEvent::Handle> buffers it independently of the kernel.
880 953
881This method may invoke callbacks (and therefore the handle might be 954This method may invoke callbacks (and therefore the handle might be
882destroyed after it returns). 955destroyed after it returns).
883 956
884=cut 957=cut
912 $cb->() unless $self->{autocork}; 985 $cb->() unless $self->{autocork};
913 986
914 # if still data left in wbuf, we need to poll 987 # if still data left in wbuf, we need to poll
915 $self->{_ww} = AE::io $self->{fh}, 1, $cb 988 $self->{_ww} = AE::io $self->{fh}, 1, $cb
916 if length $self->{wbuf}; 989 if length $self->{wbuf};
990
991 if (
992 defined $self->{wbuf_max}
993 && $self->{wbuf_max} < length $self->{wbuf}
994 ) {
995 $self->_error (Errno::ENOSPC, 1), return;
996 }
917 }; 997 };
918} 998}
919 999
920our %WH; 1000our %WH;
921 1001
992 1072
993Encodes the given hash or array reference into a JSON object. Unless you 1073Encodes the given hash or array reference into a JSON object. Unless you
994provide your own JSON object, this means it will be encoded to JSON text 1074provide your own JSON object, this means it will be encoded to JSON text
995in UTF-8. 1075in UTF-8.
996 1076
1077The default encoder might or might not handle every type of JSON value -
1078it might be limited to arrays and objects for security reasons. See the
1079C<json> constructor attribute for more details.
1080
997JSON objects (and arrays) are self-delimiting, so you can write JSON at 1081JSON objects (and arrays) are self-delimiting, so if you only use arrays
998one end of a handle and read them at the other end without using any 1082and hashes, you can write JSON at one end of a handle and read them at the
999additional framing. 1083other end without using any additional framing.
1000 1084
1001The generated JSON text is guaranteed not to contain any newlines: While 1085The JSON text generated by the default encoder is guaranteed not to
1002this module doesn't need delimiters after or between JSON texts to be 1086contain any newlines: While this module doesn't need delimiters after or
1003able to read them, many other languages depend on that. 1087between JSON texts to be able to read them, many other languages depend on
1088them.
1004 1089
1005A simple RPC protocol that interoperates easily with others is to send 1090A simple RPC protocol that interoperates easily with other languages is
1006JSON arrays (or objects, although arrays are usually the better choice as 1091to send JSON arrays (or objects, although arrays are usually the better
1007they mimic how function argument passing works) and a newline after each 1092choice as they mimic how function argument passing works) and a newline
1008JSON text: 1093after each JSON text:
1009 1094
1010 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever 1095 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
1011 $handle->push_write ("\012"); 1096 $handle->push_write ("\012");
1012 1097
1013An AnyEvent::Handle receiver would simply use the C<json> read type and 1098An AnyEvent::Handle receiver would simply use the C<json> read type and
1016 $handle->push_read (json => sub { my $array = $_[1]; ... }); 1101 $handle->push_read (json => sub { my $array = $_[1]; ... });
1017 1102
1018Other languages could read single lines terminated by a newline and pass 1103Other languages could read single lines terminated by a newline and pass
1019this line into their JSON decoder of choice. 1104this line into their JSON decoder of choice.
1020 1105
1106=item cbor => $perl_scalar
1107
1108Encodes the given scalar into a CBOR value. Unless you provide your own
1109L<CBOR::XS> object, this means it will be encoded to a CBOR string not
1110using any extensions, if possible.
1111
1112CBOR values are self-delimiting, so you can write CBOR at one end of
1113a handle and read them at the other end without using any additional
1114framing.
1115
1116A simple nd very very fast RPC protocol that interoperates with
1117other languages is to send CBOR and receive CBOR values (arrays are
1118recommended):
1119
1120 $handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
1121
1122An AnyEvent::Handle receiver would simply use the C<cbor> read type:
1123
1124 $handle->push_read (cbor => sub { my $array = $_[1]; ... });
1125
1021=cut 1126=cut
1022 1127
1023sub json_coder() { 1128sub json_coder() {
1024 eval { require JSON::XS; JSON::XS->new->utf8 } 1129 eval { require JSON::XS; JSON::XS->new->utf8 }
1025 || do { require JSON; JSON->new->utf8 } 1130 || do { require JSON::PP; JSON::PP->new->utf8 }
1026} 1131}
1027 1132
1028register_write_type json => sub { 1133register_write_type json => sub {
1029 my ($self, $ref) = @_; 1134 my ($self, $ref) = @_;
1030 1135
1031 my $json = $self->{json} ||= json_coder; 1136 ($self->{json} ||= json_coder)
1032
1033 $json->encode ($ref) 1137 ->encode ($ref)
1138};
1139
1140sub cbor_coder() {
1141 require CBOR::XS;
1142 CBOR::XS->new
1143}
1144
1145register_write_type cbor => sub {
1146 my ($self, $scalar) = @_;
1147
1148 ($self->{cbor} ||= cbor_coder)
1149 ->encode ($scalar)
1034}; 1150};
1035 1151
1036=item storable => $reference 1152=item storable => $reference
1037 1153
1038Freezes the given reference using L<Storable> and writes it to the 1154Freezes the given reference using L<Storable> and writes it to the
1041=cut 1157=cut
1042 1158
1043register_write_type storable => sub { 1159register_write_type storable => sub {
1044 my ($self, $ref) = @_; 1160 my ($self, $ref) = @_;
1045 1161
1046 require Storable; 1162 require Storable unless $Storable::VERSION;
1047 1163
1048 pack "w/a*", Storable::nfreeze ($ref) 1164 pack "w/a*", Storable::nfreeze ($ref)
1049}; 1165};
1050 1166
1051=back 1167=back
1056before it was actually written. One way to do that is to replace your 1172before it was actually written. One way to do that is to replace your
1057C<on_drain> handler by a callback that shuts down the socket (and set 1173C<on_drain> handler by a callback that shuts down the socket (and set
1058C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1174C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1059replaces the C<on_drain> callback with: 1175replaces the C<on_drain> callback with:
1060 1176
1061 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1177 sub { shutdown $_[0]{fh}, 1 }
1062 1178
1063This simply shuts down the write side and signals an EOF condition to the 1179This simply shuts down the write side and signals an EOF condition to the
1064the peer. 1180the peer.
1065 1181
1066You can rely on the normal read queue and C<on_eof> handling 1182You can rely on the normal read queue and C<on_eof> handling
1088 1204
1089Whenever the given C<type> is used, C<push_write> will the function with 1205Whenever the given C<type> is used, C<push_write> will the function with
1090the handle object and the remaining arguments. 1206the handle object and the remaining arguments.
1091 1207
1092The function is supposed to return a single octet string that will be 1208The function is supposed to return a single octet string that will be
1093appended to the write buffer, so you cna mentally treat this function as a 1209appended to the write buffer, so you can mentally treat this function as a
1094"arguments to on-the-wire-format" converter. 1210"arguments to on-the-wire-format" converter.
1095 1211
1096Example: implement a custom write type C<join> that joins the remaining 1212Example: implement a custom write type C<join> that joins the remaining
1097arguments using the first one. 1213arguments using the first one.
1098 1214
1392data. 1508data.
1393 1509
1394Example: read 2 bytes. 1510Example: read 2 bytes.
1395 1511
1396 $handle->push_read (chunk => 2, sub { 1512 $handle->push_read (chunk => 2, sub {
1397 warn "yay ", unpack "H*", $_[1]; 1513 say "yay " . unpack "H*", $_[1];
1398 }); 1514 });
1399 1515
1400=cut 1516=cut
1401 1517
1402register_read_type chunk => sub { 1518register_read_type chunk => sub {
1432 1548
1433register_read_type line => sub { 1549register_read_type line => sub {
1434 my ($self, $cb, $eol) = @_; 1550 my ($self, $cb, $eol) = @_;
1435 1551
1436 if (@_ < 3) { 1552 if (@_ < 3) {
1437 # this is more than twice as fast as the generic code below 1553 # this is faster then the generic code below
1438 sub { 1554 sub {
1439 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1555 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1556 or return;
1440 1557
1558 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1441 $cb->($_[0], $1, $2); 1559 $cb->($_[0], $str, "$1");
1442 1 1560 1
1443 } 1561 }
1444 } else { 1562 } else {
1445 $eol = quotemeta $eol unless ref $eol; 1563 $eol = quotemeta $eol unless ref $eol;
1446 $eol = qr|^(.*?)($eol)|s; 1564 $eol = qr|^(.*?)($eol)|s;
1447 1565
1448 sub { 1566 sub {
1449 $_[0]{rbuf} =~ s/$eol// or return; 1567 $_[0]{rbuf} =~ s/$eol// or return;
1450 1568
1451 $cb->($_[0], $1, $2); 1569 $cb->($_[0], "$1", "$2");
1452 1 1570 1
1453 } 1571 }
1454 } 1572 }
1455}; 1573};
1456 1574
1504 1622
1505 sub { 1623 sub {
1506 # accept 1624 # accept
1507 if ($$rbuf =~ $accept) { 1625 if ($$rbuf =~ $accept) {
1508 $data .= substr $$rbuf, 0, $+[0], ""; 1626 $data .= substr $$rbuf, 0, $+[0], "";
1509 $cb->($self, $data); 1627 $cb->($_[0], $data);
1510 return 1; 1628 return 1;
1511 } 1629 }
1512 1630
1513 # reject 1631 # reject
1514 if ($reject && $$rbuf =~ $reject) { 1632 if ($reject && $$rbuf =~ $reject) {
1515 $self->_error (Errno::EBADMSG); 1633 $_[0]->_error (Errno::EBADMSG);
1516 } 1634 }
1517 1635
1518 # skip 1636 # skip
1519 if ($skip && $$rbuf =~ $skip) { 1637 if ($skip && $$rbuf =~ $skip) {
1520 $data .= substr $$rbuf, 0, $+[0], ""; 1638 $data .= substr $$rbuf, 0, $+[0], "";
1536 my ($self, $cb) = @_; 1654 my ($self, $cb) = @_;
1537 1655
1538 sub { 1656 sub {
1539 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1657 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1540 if ($_[0]{rbuf} =~ /[^0-9]/) { 1658 if ($_[0]{rbuf} =~ /[^0-9]/) {
1541 $self->_error (Errno::EBADMSG); 1659 $_[0]->_error (Errno::EBADMSG);
1542 } 1660 }
1543 return; 1661 return;
1544 } 1662 }
1545 1663
1546 my $len = $1; 1664 my $len = $1;
1547 1665
1548 $self->unshift_read (chunk => $len, sub { 1666 $_[0]->unshift_read (chunk => $len, sub {
1549 my $string = $_[1]; 1667 my $string = $_[1];
1550 $_[0]->unshift_read (chunk => 1, sub { 1668 $_[0]->unshift_read (chunk => 1, sub {
1551 if ($_[1] eq ",") { 1669 if ($_[1] eq ",") {
1552 $cb->($_[0], $string); 1670 $cb->($_[0], $string);
1553 } else { 1671 } else {
1554 $self->_error (Errno::EBADMSG); 1672 $_[0]->_error (Errno::EBADMSG);
1555 } 1673 }
1556 }); 1674 });
1557 }); 1675 });
1558 1676
1559 1 1677 1
1609=item json => $cb->($handle, $hash_or_arrayref) 1727=item json => $cb->($handle, $hash_or_arrayref)
1610 1728
1611Reads a JSON object or array, decodes it and passes it to the 1729Reads a JSON object or array, decodes it and passes it to the
1612callback. When a parse error occurs, an C<EBADMSG> error will be raised. 1730callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1613 1731
1614If a C<json> object was passed to the constructor, then that will be used 1732If a C<json> object was passed to the constructor, then that will be
1615for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1733used for the final decode, otherwise it will create a L<JSON::XS> or
1734L<JSON::PP> coder object expecting UTF-8.
1616 1735
1617This read type uses the incremental parser available with JSON version 1736This read type uses the incremental parser available with JSON version
16182.09 (and JSON::XS version 2.2) and above. You have to provide a 17372.09 (and JSON::XS version 2.2) and above.
1619dependency on your own: this module will load the JSON module, but
1620AnyEvent does not depend on it itself.
1621 1738
1622Since JSON texts are fully self-delimiting, the C<json> read and write 1739Since JSON texts are fully self-delimiting, the C<json> read and write
1623types are an ideal simple RPC protocol: just exchange JSON datagrams. See 1740types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1624the C<json> write type description, above, for an actual example. 1741the C<json> write type description, above, for an actual example.
1625 1742
1629 my ($self, $cb) = @_; 1746 my ($self, $cb) = @_;
1630 1747
1631 my $json = $self->{json} ||= json_coder; 1748 my $json = $self->{json} ||= json_coder;
1632 1749
1633 my $data; 1750 my $data;
1634 my $rbuf = \$self->{rbuf};
1635 1751
1636 sub { 1752 sub {
1637 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1753 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1638 1754
1639 if ($ref) { 1755 if ($ref) {
1640 $self->{rbuf} = $json->incr_text; 1756 $_[0]{rbuf} = $json->incr_text;
1641 $json->incr_text = ""; 1757 $json->incr_text = "";
1642 $cb->($self, $ref); 1758 $cb->($_[0], $ref);
1643 1759
1644 1 1760 1
1645 } elsif ($@) { 1761 } elsif ($@) {
1646 # error case 1762 # error case
1647 $json->incr_skip; 1763 $json->incr_skip;
1648 1764
1649 $self->{rbuf} = $json->incr_text; 1765 $_[0]{rbuf} = $json->incr_text;
1650 $json->incr_text = ""; 1766 $json->incr_text = "";
1651 1767
1652 $self->_error (Errno::EBADMSG); 1768 $_[0]->_error (Errno::EBADMSG);
1653 1769
1654 () 1770 ()
1655 } else { 1771 } else {
1656 $self->{rbuf} = ""; 1772 $_[0]{rbuf} = "";
1657 1773
1774 ()
1775 }
1776 }
1777};
1778
1779=item cbor => $cb->($handle, $scalar)
1780
1781Reads a CBOR value, decodes it and passes it to the callback. When a parse
1782error occurs, an C<EBADMSG> error will be raised.
1783
1784If a L<CBOR::XS> object was passed to the constructor, then that will be
1785used for the final decode, otherwise it will create a CBOR coder without
1786enabling any options.
1787
1788You have to provide a dependency to L<CBOR::XS> on your own: this module
1789will load the L<CBOR::XS> module, but AnyEvent does not depend on it
1790itself.
1791
1792Since CBOR values are fully self-delimiting, the C<cbor> read and write
1793types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
1794the C<cbor> write type description, above, for an actual example.
1795
1796=cut
1797
1798register_read_type cbor => sub {
1799 my ($self, $cb) = @_;
1800
1801 my $cbor = $self->{cbor} ||= cbor_coder;
1802
1803 my $data;
1804
1805 sub {
1806 my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
1807
1808 if (@value) {
1809 $cb->($_[0], @value);
1810
1811 1
1812 } elsif ($@) {
1813 # error case
1814 $cbor->incr_reset;
1815
1816 $_[0]->_error (Errno::EBADMSG);
1817
1818 ()
1819 } else {
1658 () 1820 ()
1659 } 1821 }
1660 } 1822 }
1661}; 1823};
1662 1824
1671=cut 1833=cut
1672 1834
1673register_read_type storable => sub { 1835register_read_type storable => sub {
1674 my ($self, $cb) = @_; 1836 my ($self, $cb) = @_;
1675 1837
1676 require Storable; 1838 require Storable unless $Storable::VERSION;
1677 1839
1678 sub { 1840 sub {
1679 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1841 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1680 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1842 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1681 or return; 1843 or return;
1684 1846
1685 # bypass unshift if we already have the remaining chunk 1847 # bypass unshift if we already have the remaining chunk
1686 if ($format + $len <= length $_[0]{rbuf}) { 1848 if ($format + $len <= length $_[0]{rbuf}) {
1687 my $data = substr $_[0]{rbuf}, $format, $len; 1849 my $data = substr $_[0]{rbuf}, $format, $len;
1688 substr $_[0]{rbuf}, 0, $format + $len, ""; 1850 substr $_[0]{rbuf}, 0, $format + $len, "";
1851
1689 $cb->($_[0], Storable::thaw ($data)); 1852 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1853 or return $_[0]->_error (Errno::EBADMSG);
1690 } else { 1854 } else {
1691 # remove prefix 1855 # remove prefix
1692 substr $_[0]{rbuf}, 0, $format, ""; 1856 substr $_[0]{rbuf}, 0, $format, "";
1693 1857
1694 # read remaining chunk 1858 # read remaining chunk
1695 $_[0]->unshift_read (chunk => $len, sub { 1859 $_[0]->unshift_read (chunk => $len, sub {
1696 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1860 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1697 $cb->($_[0], $ref);
1698 } else {
1699 $self->_error (Errno::EBADMSG); 1861 or $_[0]->_error (Errno::EBADMSG);
1700 }
1701 }); 1862 });
1702 } 1863 }
1703 1864
1704 1 1865 1
1705 } 1866 }
1867};
1868
1869=item tls_detect => $cb->($handle, $detect, $major, $minor)
1870
1871Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1872record without consuming anything. Only SSL version 3 or higher
1873is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1874SSL2-compatible framing is supported).
1875
1876If it detects that the input data is likely TLS, it calls the callback
1877with a true value for C<$detect> and the (on-wire) TLS version as second
1878and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
18793.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1880be definitely not TLS, it calls the callback with a false value for
1881C<$detect>.
1882
1883The callback could use this information to decide whether or not to start
1884TLS negotiation.
1885
1886In all cases the data read so far is passed to the following read
1887handlers.
1888
1889Usually you want to use the C<tls_autostart> read type instead.
1890
1891If you want to design a protocol that works in the presence of TLS
1892dtection, make sure that any non-TLS data doesn't start with the octet 22
1893(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1894read type does are a bit more strict, but might losen in the future to
1895accomodate protocol changes.
1896
1897This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1898L<Net::SSLeay>).
1899
1900=item tls_autostart => $tls[, $tls_ctx]
1901
1902Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1903to start tls by calling C<starttls> with the given arguments.
1904
1905In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1906been configured to accept, as servers do not normally send a handshake on
1907their own and ths cannot be detected in this way.
1908
1909See C<tls_detect> above for more details.
1910
1911Example: give the client a chance to start TLS before accepting a text
1912line.
1913
1914 $hdl->push_read (tls_detect => "accept");
1915 $hdl->push_read (line => sub {
1916 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1917 });
1918
1919=cut
1920
1921register_read_type tls_detect => sub {
1922 my ($self, $cb) = @_;
1923
1924 sub {
1925 # this regex matches a full or partial tls record
1926 if (
1927 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1928 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1929 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1930 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1931 ) {
1932 return if 3 != length $1; # partial match, can't decide yet
1933
1934 # full match, valid TLS record
1935 my ($major, $minor) = unpack "CC", $1;
1936 $cb->($self, "accept", $major + $minor * 0.1);
1937 } else {
1938 # mismatch == guaranteed not TLS
1939 $cb->($self, undef);
1940 }
1941
1942 1
1943 }
1944};
1945
1946register_read_type tls_autostart => sub {
1947 my ($self, @tls) = @_;
1948
1949 $RH{tls_detect}($self, sub {
1950 return unless $_[1];
1951 $_[0]->starttls (@tls);
1952 })
1706}; 1953};
1707 1954
1708=back 1955=back
1709 1956
1710=item custom read types - Package::anyevent_read_type $handle, $cb, @args 1957=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1742Note that AnyEvent::Handle will automatically C<start_read> for you when 1989Note that AnyEvent::Handle will automatically C<start_read> for you when
1743you change the C<on_read> callback or push/unshift a read callback, and it 1990you change the C<on_read> callback or push/unshift a read callback, and it
1744will automatically C<stop_read> for you when neither C<on_read> is set nor 1991will automatically C<stop_read> for you when neither C<on_read> is set nor
1745there are any read requests in the queue. 1992there are any read requests in the queue.
1746 1993
1747These methods will have no effect when in TLS mode (as TLS doesn't support 1994In older versions of this module (<= 5.3), these methods had no effect,
1748half-duplex connections). 1995as TLS does not support half-duplex connections. In current versions they
1996work as expected, as this behaviour is required to avoid certain resource
1997attacks, where the program would be forced to read (and buffer) arbitrary
1998amounts of data before being able to send some data. The drawback is that
1999some readings of the the SSL/TLS specifications basically require this
2000attack to be working, as SSL/TLS implementations might stall sending data
2001during a rehandshake.
2002
2003As a guideline, during the initial handshake, you should not stop reading,
2004and as a client, it might cause problems, depending on your application.
1749 2005
1750=cut 2006=cut
1751 2007
1752sub stop_read { 2008sub stop_read {
1753 my ($self) = @_; 2009 my ($self) = @_;
1754 2010
1755 delete $self->{_rw} unless $self->{tls}; 2011 delete $self->{_rw};
1756} 2012}
1757 2013
1758sub start_read { 2014sub start_read {
1759 my ($self) = @_; 2015 my ($self) = @_;
1760 2016
1801 my ($self, $err) = @_; 2057 my ($self, $err) = @_;
1802 2058
1803 return $self->_error ($!, 1) 2059 return $self->_error ($!, 1)
1804 if $err == Net::SSLeay::ERROR_SYSCALL (); 2060 if $err == Net::SSLeay::ERROR_SYSCALL ();
1805 2061
1806 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 2062 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1807 2063
1808 # reduce error string to look less scary 2064 # reduce error string to look less scary
1809 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 2065 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1810 2066
1811 if ($self->{_on_starttls}) { 2067 if ($self->{_on_starttls}) {
1825sub _dotls { 2081sub _dotls {
1826 my ($self) = @_; 2082 my ($self) = @_;
1827 2083
1828 my $tmp; 2084 my $tmp;
1829 2085
1830 if (length $self->{_tls_wbuf}) { 2086 while (length $self->{_tls_wbuf}) {
1831 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 2087 if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
1832 substr $self->{_tls_wbuf}, 0, $tmp, ""; 2088 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
2089
2090 return $self->_tls_error ($tmp)
2091 if $tmp != $ERROR_WANT_READ
2092 && ($tmp != $ERROR_SYSCALL || $!);
2093
2094 last;
1833 } 2095 }
1834 2096
1835 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp); 2097 substr $self->{_tls_wbuf}, 0, $tmp, "";
1836 return $self->_tls_error ($tmp)
1837 if $tmp != $ERROR_WANT_READ
1838 && ($tmp != $ERROR_SYSCALL || $!);
1839 } 2098 }
1840 2099
1841 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 2100 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1842 unless (length $tmp) { 2101 unless (length $tmp) {
1843 $self->{_on_starttls} 2102 $self->{_on_starttls}
1857 $self->{_tls_rbuf} .= $tmp; 2116 $self->{_tls_rbuf} .= $tmp;
1858 $self->_drain_rbuf; 2117 $self->_drain_rbuf;
1859 $self->{tls} or return; # tls session might have gone away in callback 2118 $self->{tls} or return; # tls session might have gone away in callback
1860 } 2119 }
1861 2120
1862 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 2121 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
1863 return $self->_tls_error ($tmp) 2122 return $self->_tls_error ($tmp)
1864 if $tmp != $ERROR_WANT_READ 2123 if $tmp != $ERROR_WANT_READ
1865 && ($tmp != $ERROR_SYSCALL || $!); 2124 && ($tmp != $ERROR_SYSCALL || $!);
1866 2125
1867 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2126 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1877 2136
1878=item $handle->starttls ($tls[, $tls_ctx]) 2137=item $handle->starttls ($tls[, $tls_ctx])
1879 2138
1880Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2139Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1881object is created, you can also do that at a later time by calling 2140object is created, you can also do that at a later time by calling
1882C<starttls>. 2141C<starttls>. See the C<tls> constructor argument for general info.
1883 2142
1884Starting TLS is currently an asynchronous operation - when you push some 2143Starting TLS is currently an asynchronous operation - when you push some
1885write data and then call C<< ->starttls >> then TLS negotiation will start 2144write data and then call C<< ->starttls >> then TLS negotiation will start
1886immediately, after which the queued write data is then sent. 2145immediately, after which the queued write data is then sent. This might
2146change in future versions, so best make sure you have no outstanding write
2147data when calling this method.
1887 2148
1888The first argument is the same as the C<tls> constructor argument (either 2149The first argument is the same as the C<tls> constructor argument (either
1889C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2150C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1890 2151
1891The second argument is the optional C<AnyEvent::TLS> object that is used 2152The second argument is the optional C<AnyEvent::TLS> object that is used
1913 my ($self, $tls, $ctx) = @_; 2174 my ($self, $tls, $ctx) = @_;
1914 2175
1915 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 2176 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1916 if $self->{tls}; 2177 if $self->{tls};
1917 2178
2179 unless (defined $AnyEvent::TLS::VERSION) {
2180 eval {
2181 require Net::SSLeay;
2182 require AnyEvent::TLS;
2183 1
2184 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2185 }
2186
1918 $self->{tls} = $tls; 2187 $self->{tls} = $tls;
1919 $self->{tls_ctx} = $ctx if @_ > 2; 2188 $self->{tls_ctx} = $ctx if @_ > 2;
1920 2189
1921 return unless $self->{fh}; 2190 return unless $self->{fh};
1922 2191
1923 require Net::SSLeay;
1924
1925 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2192 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1926 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2193 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1927 2194
1928 $tls = delete $self->{tls}; 2195 $tls = delete $self->{tls};
1929 $ctx = $self->{tls_ctx}; 2196 $ctx = $self->{tls_ctx};
1930 2197
1931 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2198 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1932 2199
1933 if ("HASH" eq ref $ctx) { 2200 if ("HASH" eq ref $ctx) {
1934 require AnyEvent::TLS;
1935
1936 if ($ctx->{cache}) { 2201 if ($ctx->{cache}) {
1937 my $key = $ctx+0; 2202 my $key = $ctx+0;
1938 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2203 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1939 } else { 2204 } else {
1940 $ctx = new AnyEvent::TLS %$ctx; 2205 $ctx = new AnyEvent::TLS %$ctx;
1962 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2227 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1963 2228
1964 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2229 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1965 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2230 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1966 2231
1967 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2232 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2233 $self->{rbuf} = "";
1968 2234
1969 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2235 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1970 2236
1971 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2237 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1972 if $self->{on_starttls}; 2238 if $self->{on_starttls};
2009 $self->{tls_ctx}->_put_session (delete $self->{tls}) 2275 $self->{tls_ctx}->_put_session (delete $self->{tls})
2010 if $self->{tls} > 0; 2276 if $self->{tls} > 0;
2011 2277
2012 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2278 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2013} 2279}
2280
2281=item $handle->resettls
2282
2283This rarely-used method simply resets and TLS state on the handle, usually
2284causing data loss.
2285
2286One case where it may be useful is when you want to skip over the data in
2287the stream but you are not interested in interpreting it, so data loss is
2288no concern.
2289
2290=cut
2291
2292*resettls = \&_freetls;
2014 2293
2015sub DESTROY { 2294sub DESTROY {
2016 my ($self) = @_; 2295 my ($self) = @_;
2017 2296
2018 &_freetls; 2297 &_freetls;
2134 2413
2135It is only safe to "forget" the reference inside EOF or error callbacks, 2414It is only safe to "forget" the reference inside EOF or error callbacks,
2136from within all other callbacks, you need to explicitly call the C<< 2415from within all other callbacks, you need to explicitly call the C<<
2137->destroy >> method. 2416->destroy >> method.
2138 2417
2418=item Why is my C<on_eof> callback never called?
2419
2420Probably because your C<on_error> callback is being called instead: When
2421you have outstanding requests in your read queue, then an EOF is
2422considered an error as you clearly expected some data.
2423
2424To avoid this, make sure you have an empty read queue whenever your handle
2425is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2426an C<on_read> handler that simply pushes the first read requests in the
2427queue.
2428
2429See also the next question, which explains this in a bit more detail.
2430
2431=item How can I serve requests in a loop?
2432
2433Most protocols consist of some setup phase (authentication for example)
2434followed by a request handling phase, where the server waits for requests
2435and handles them, in a loop.
2436
2437There are two important variants: The first (traditional, better) variant
2438handles requests until the server gets some QUIT command, causing it to
2439close the connection first (highly desirable for a busy TCP server). A
2440client dropping the connection is an error, which means this variant can
2441detect an unexpected detection close.
2442
2443To handle this case, always make sure you have a non-empty read queue, by
2444pushing the "read request start" handler on it:
2445
2446 # we assume a request starts with a single line
2447 my @start_request; @start_request = (line => sub {
2448 my ($hdl, $line) = @_;
2449
2450 ... handle request
2451
2452 # push next request read, possibly from a nested callback
2453 $hdl->push_read (@start_request);
2454 });
2455
2456 # auth done, now go into request handling loop
2457 # now push the first @start_request
2458 $hdl->push_read (@start_request);
2459
2460By always having an outstanding C<push_read>, the handle always expects
2461some data and raises the C<EPIPE> error when the connction is dropped
2462unexpectedly.
2463
2464The second variant is a protocol where the client can drop the connection
2465at any time. For TCP, this means that the server machine may run out of
2466sockets easier, and in general, it means you cannot distinguish a protocl
2467failure/client crash from a normal connection close. Nevertheless, these
2468kinds of protocols are common (and sometimes even the best solution to the
2469problem).
2470
2471Having an outstanding read request at all times is possible if you ignore
2472C<EPIPE> errors, but this doesn't help with when the client drops the
2473connection during a request, which would still be an error.
2474
2475A better solution is to push the initial request read in an C<on_read>
2476callback. This avoids an error, as when the server doesn't expect data
2477(i.e. is idly waiting for the next request, an EOF will not raise an
2478error, but simply result in an C<on_eof> callback. It is also a bit slower
2479and simpler:
2480
2481 # auth done, now go into request handling loop
2482 $hdl->on_read (sub {
2483 my ($hdl) = @_;
2484
2485 # called each time we receive data but the read queue is empty
2486 # simply start read the request
2487
2488 $hdl->push_read (line => sub {
2489 my ($hdl, $line) = @_;
2490
2491 ... handle request
2492
2493 # do nothing special when the request has been handled, just
2494 # let the request queue go empty.
2495 });
2496 });
2497
2139=item I get different callback invocations in TLS mode/Why can't I pause 2498=item I get different callback invocations in TLS mode/Why can't I pause
2140reading? 2499reading?
2141 2500
2142Unlike, say, TCP, TLS connections do not consist of two independent 2501Unlike, say, TCP, TLS connections do not consist of two independent
2143communication channels, one for each direction. Or put differently, the 2502communication channels, one for each direction. Or put differently, the
2164 $handle->on_eof (undef); 2523 $handle->on_eof (undef);
2165 $handle->on_error (sub { 2524 $handle->on_error (sub {
2166 my $data = delete $_[0]{rbuf}; 2525 my $data = delete $_[0]{rbuf};
2167 }); 2526 });
2168 2527
2528Note that this example removes the C<rbuf> member from the handle object,
2529which is not normally allowed by the API. It is expressly permitted in
2530this case only, as the handle object needs to be destroyed afterwards.
2531
2169The reason to use C<on_error> is that TCP connections, due to latencies 2532The reason to use C<on_error> is that TCP connections, due to latencies
2170and packets loss, might get closed quite violently with an error, when in 2533and packets loss, might get closed quite violently with an error, when in
2171fact all data has been received. 2534fact all data has been received.
2172 2535
2173It is usually better to use acknowledgements when transferring data, 2536It is usually better to use acknowledgements when transferring data,
2183C<low_water_mark> this will be called precisely when all data has been 2546C<low_water_mark> this will be called precisely when all data has been
2184written to the socket: 2547written to the socket:
2185 2548
2186 $handle->push_write (...); 2549 $handle->push_write (...);
2187 $handle->on_drain (sub { 2550 $handle->on_drain (sub {
2188 warn "all data submitted to the kernel\n"; 2551 AE::log debug => "All data submitted to the kernel.";
2189 undef $handle; 2552 undef $handle;
2190 }); 2553 });
2191 2554
2192If you just want to queue some data and then signal EOF to the other side, 2555If you just want to queue some data and then signal EOF to the other side,
2193consider using C<< ->push_shutdown >> instead. 2556consider using C<< ->push_shutdown >> instead.
2277When you have intermediate CA certificates that your clients might not 2640When you have intermediate CA certificates that your clients might not
2278know about, just append them to the C<cert_file>. 2641know about, just append them to the C<cert_file>.
2279 2642
2280=back 2643=back
2281 2644
2282
2283=head1 SUBCLASSING AnyEvent::Handle 2645=head1 SUBCLASSING AnyEvent::Handle
2284 2646
2285In many cases, you might want to subclass AnyEvent::Handle. 2647In many cases, you might want to subclass AnyEvent::Handle.
2286 2648
2287To make this easier, a given version of AnyEvent::Handle uses these 2649To make this easier, a given version of AnyEvent::Handle uses these
2313 2675
2314Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2676Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2315 2677
2316=cut 2678=cut
2317 2679
23181; # End of AnyEvent::Handle 26801
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